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1

QCD Level Density from Maximum Entropy Method  

E-Print Network [OSTI]

We propose a method to calculate the QCD level density directly from the thermodynamic quantities obtained by lattice QCD simulations with the use of the maximum entropy method (MEM). Understanding QCD thermodynamics from QCD spectral properties has its own importance. Also it has a close connection to phenomenological analyses of the lattice data as well as experimental data on the basis of hadronic resonances. Our feasibility study shows that the MEM can provide a useful tool to study QCD level density.

Shinji Ejiri; Tetsuo Hatsuda

2005-09-24T23:59:59.000Z

2

Maximum Photovoltaic Penetration Levels on Typical Distribution Feeders: Preprint  

SciTech Connect (OSTI)

This paper presents simulation results for a taxonomy of typical distribution feeders with various levels of photovoltaic (PV) penetration. For each of the 16 feeders simulated, the maximum PV penetration that did not result in steady-state voltage or current violation is presented for several PV location scenarios: clustered near the feeder source, clustered near the midpoint of the feeder, clustered near the end of the feeder, randomly located, and evenly distributed. In addition, the maximum level of PV is presented for single, large PV systems at each location. Maximum PV penetration was determined by requiring that feeder voltages stay within ANSI Range A and that feeder currents stay within the ranges determined by overcurrent protection devices. Simulations were run in GridLAB-D using hourly time steps over a year with randomized load profiles based on utility data and typical meteorological year weather data. For 86% of the cases simulated, maximum PV penetration was at least 30% of peak load.

Hoke, A.; Butler, R.; Hambrick, J.; Kroposki, B.

2012-07-01T23:59:59.000Z

3

Maximum surface level and temperature histories for Hanford waste tanks  

SciTech Connect (OSTI)

Radioactive defense waste resulting from the chemical processing of spent nuclear fuel has been accumulating at the Hanford Site since 1944. This waste is stored in underground waste-storage tanks. The Hanford Site Tank Farm Facilities Interim Safety Basis (ISB) provides a ready reference to the safety envelope for applicable tank farm facilities and installations. During preparation of the ISB, tank structural integrity concerns were identified as a key element in defining the safety envelope. These concerns, along with several deficiencies in the technical bases associated with the structural integrity issues and the corresponding operational limits/controls specified for conduct of normal tank farm operations are documented in the ISB. Consequently, a plan was initiated to upgrade the safety envelope technical bases by conducting Accelerated Safety Analyses-Phase 1 (ASA-Phase 1) sensitivity studies and additional structural evaluations. The purpose of this report is to facilitate the ASA-Phase 1 studies and future analyses of the single-shell tanks (SSTs) and double-shell tanks (DSTs) by compiling a quantitative summary of some of the past operating conditions the tanks have experienced during their existence. This report documents the available summaries of recorded maximum surface levels and maximum waste temperatures and references other sources for more specific data.

Flanagan, B.D.; Ha, N.D.; Huisingh, J.S.

1994-09-02T23:59:59.000Z

4

Remediation alternatives for low-level herbicide contaminated groundwater  

SciTech Connect (OSTI)

In early 1995, an evaluation of alternatives for remediation of a shallow groundwater plume containing low-levels of an organic herbicide was conducted at BASF Corporation, a petrochemical facility located in Ascension Parish, Louisiana. The contaminated site is located on an undeveloped portion of property within 1/4 mile of the east bank of the Mississippi River near the community of Geismar. Environmental assessment data indicated that about two acres of the thirty acre site had been contaminated from past waste management practices with the herbicide bentazon. Shallow soils and groundwater between 5 to 15 feet in depth were affected. Maximum concentrations of bentazon in groundwater were less than seven parts per million. To identify potentially feasible remediation alternatives, the environmental assessment data, available research, and cost effectiveness were reviewed. After consideration of a preliminary list of alternatives, only two potentially feasible alternatives could be identified. Groundwater pumping, the most commonly used remediation alternative, followed by carbon adsorption treatment was identified as was a new innovative alternative known as vegetative transpiration. This alternative relies on the natural transpiration processes of vegetation to bioremediate organic contaminants. Advantages identified during screening suggest that the transpiration method could be the best remediation alternative to address both economic and environmental factors. An experiment to test critical factors of the vegetatived transpiration alternative with bentazon was recommended before a final decision on feasibility can be made.

Conger, R.M. [BASF Corp., Geismar, LA (United States)

1995-10-01T23:59:59.000Z

5

Treatment options for low-level radiologically contaminated ORNL filtercake  

SciTech Connect (OSTI)

Water softening sludge (>4000 stored low level contaminated drums; 600 drums per year) generated by the ORNL Process Waste Treatment Plant must be treated, stabilized, and placed in safe storage/disposal. The sludge is primarily CaCO{sub 3} and is contaminated by low levels of {sup 90}Sr and {sup 137}Cs. In this study, microwave sintering and calcination were evaluated for treating the sludge. The microwave melting experiments showed promise: volume reductions were significant (3-5X), and the waste form was durable with glass additives (LiOH, fly ash). A commercial vendor using surrogate has demonstrated a melt mineralization process that yields a dense monolithic waste form with a volume reduction factor (VR) of 7.7. Calcination of the sludge at 850-900 C yielded a VR of 2.5. Compaction at 4500 psi increased the VR to 4.2, but the compressed form is not dimensionally stable. Addition of paraffin helped consolidate fines and yielded a VR of 3.5. In conclusion, microwave melting or another form of vitrification is likely to be the best method; however for immediate implementation, the calculation/compaction/waxing process is viable.

Lee, Hom-Ti [Oak Ridge Associated Universities, Inc., TN (United States); Bostick, W.D. [Oak Ridge K-25 Site, TN (United States)

1996-04-01T23:59:59.000Z

6

Residual radioactive contamination from decommissioning: Technical basis for translating contamination levels to annual dose  

SciTech Connect (OSTI)

This document describes the generic modeling of the total effective dose equivalent (TEDE) to an individual in a population from a unit concentration of residual radioactive contamination. Radioactive contamination inside buildings and soil contamination are considered. Unit concentration TEDE factors by radionuclide, exposure pathway, and exposure scenario are calculated. Reference radiation exposure scenarios are used to derive unit concentration TEDE factors for about 200 individual radionuclides and parent-daughter mixtures. For buildings, these unit concentration factors list the annual TEDE for volume and surface contamination situations. For soil, annual TEDE factors are presented for unit concentrations of radionuclides in soil during residential use of contaminated land and the TEDE per unit total inventory for potential use of drinking water from a ground-water source. Because of the generic treatment of potentially complex ground-water systems, the annual TEDE factors for drinking water for a given inventory may only indicate when additional site data or modeling sophistication are warranted. Descriptions are provided of the models, exposure pathways, exposure scenarios, parameter values, and assumptions used. An analysis of the potential annual TEDE resulting from reference mixtures of residual radionuclides is provided to demonstrate application of the TEDE factors. 62 refs., 5 figs., 66 tabs.

Kennedy, W.E. Jr.; Peloquin, R.A. (Pacific Northwest Lab., Richland, WA (USA))

1990-01-01T23:59:59.000Z

7

Allowable residual-contamination levels for decommissioning facilities in the 100 areas of the Hanford Site  

SciTech Connect (OSTI)

This report contains the results of a study sponsored by UNC Nuclear Industries to determine Allowable Residual Contamination Levels (ARCL) for five generic categories of facilities in the 100 Areas of the Hanford Site. The purpose of this study is to provide ARCL data useful to UNC engineers in conducting safety and cost comparisons for decommissioning alternatives. The ARCL results are based on a scenario/exposure-pathway analysis and compliance with an annual dose limit for three specific modes of future use of the land and facilities. These modes of use are restricted, controlled, and unrestricted. The information on ARCL values for restricted and controlled use provided by this report is intended to permit a full consideration of decommissioning alternatives. ARCL results are presented both for surface contamination remaining in facilities (in dpm/100 cm/sup 2/), and for unconfined surface and confined subsurface soil conditions (in pCi/g). Two confined soil conditions are considered: contamination at depths between 1 and 4 m, and contamination at depths greater than or equal to 5 m. A set of worksheets are presented in an appendix for modifying the ARCL values to accommodate changes in the radionuclide mixture or concentrations, to consider the impacts of radioactive decay, and to predict instrument responses. Finally, a comparison is made between the unrestricted release ARCL values for the 100 Area facilities and existing decommissioning and land disposal regulations. For surface contamination, the comparison shows good agreement. For soil contamination, the comparison shows good agreement if reasonable modification factors are applied to account for the differences in modeling soil contamination and licensed low-level waste.

Kennedy, W.E. Jr.; Napier, B.A.

1983-07-01T23:59:59.000Z

8

Contamination levels of human pharmaceutical compounds in French surface and drinking water  

E-Print Network [OSTI]

-west France. 98 samples were analysed from 63 stations (surface water and drinking water produced from surfaceContamination levels of human pharmaceutical compounds in French surface and drinking water S therapeutic classes was analysed from resource and drinking water in two catchment basins located in north

Paris-Sud XI, Université de

9

Red Sea during the Last Glacial Maximum: Implications for sea level reconstruction  

E-Print Network [OSTI]

. Gildor,1 and W. R. Peltier2 Received 13 February 2007; revised 29 July 2007; accepted 30 October 2007 based on the ICE-5G (VM2) model. Citation: Biton, E., H. Gildor, and W. R. Peltier (2008), Red Sea sea level reduction for the LGM interval range between approximately 120 m [Peltier, 2004, 2002

Peltier, W. Richard

10

On the ro-vibrational energies for the lithium dimer; maximum-possible rotational levels  

E-Print Network [OSTI]

The Deng-Fan potential is used to discuss the reliability of the improved Greene-Aldrich approximation and the factorization recipe of Badawi et al.'s [17] for the central attractive/repulsive core. The factorization recipe is shown to be a more reliable approximation and is used to obtain the ro-vibrational energies for the lithium dimer. For each vibrational state only a limited number of the rotational levels are found to be supported by the lithium dimer.

Omar Mustafa

2015-03-02T23:59:59.000Z

11

On the ro-vibrational energies for the lithium dimer; maximum-possible rotational levels  

E-Print Network [OSTI]

The Deng-Fan potential is used to discuss the reliability of the improved Greene-Aldrich approximation and the factorization recipe of Badawi et al.'s [17] for the central attractive/repulsive core. The factorization recipe is shown to be a more reliable approximation and is used to obtain the ro-vibrational energies for the lithium dimer. For each vibrational state only a limited number of the rotational levels are found to be supported by the lithium dimer.

Omar Mustafa

2015-01-27T23:59:59.000Z

12

Prediction of risk-based screening levels for infiltration of volatile subsurface contaminants into buildings  

SciTech Connect (OSTI)

A Risk-Based Corrective Action (RBCA) approach is increasingly being used for the management of contaminated sites. Fundamental to this approach is the prediction of risk-based screening levels (RBSL) for operable exposure pathways. Screening level models currently used indicate that RBSLs for the indoor inhalation pathway can be significantly lower than other pathways typically considered. This paper presents the results of a screening level spreadsheet model used to predict human health risks resulting from infiltration of volatile organic compounds (VOCs) into buildings. The model was developed to derive RBSLs for soil and groundwater for possible future incorporation into the regulation of contaminated sites in British Columbia. Key features of the semi-analytical VOC infiltration model are steady-state diffusive mass transfer through soil coupled with advective and diffusive mass transfer through a cracked building floor slab or wall, source mass depletion of soil contaminants present using a mass balance approach, and the capability to incorporate multi-component chemical partitioning for soils containing non-aqueous phase liquid (NAPL). The critical factors affecting VOC infiltration and resulting health risks are presented.

Hers, I.; Zapf-Gilje, R.; Petrovic, S. [Golder Associates Ltd., Burnaby, British Columbia (Canada); Macfarlane, M.; McLenehan, R. [British Columbia Ministry of Environment, Lands and Parks, Victoria, British Columbia (Canada)

1997-09-01T23:59:59.000Z

13

New Remote Method for Estimation of Contamination Levels of Reactor Equipment - 13175  

SciTech Connect (OSTI)

Projects for decommissioning of shutdown reactors and reactor facilities carried out in several countries, including Russia. In the National Research Centre 'Kurchatov Institute' decontamination and decommissioning of the research reactor MR (Material Testing Reactor) has been initiated. The research reactor MR has a long history and consists of nine loop facilities for experiments with different kinds of fuel. During the operation of main and auxiliary equipment of reactors it was subjected to strong radioactive contamination. The character of this contamination requires individual strategies for the decontamination work. This requires information about the character of the distribution of radioactive contamination of equipment in the premises. A detailed radiation survey of these premises using standard dosimetric equipment is almost impossible because of high levels of radiation and high-density of the equipment that does not allow identifying the most active fragments using standard tools of measurement. The problem can be solved using the method of remote measurements of distribution of radioactivity with help of the collimated gamma-ray detectors. For radiation surveys of the premises of loop installations remotely operated spectrometric collimated system was used [1, 2, 3]. As a result of the work, maps of the distribution of activity and dose rate for surveyed premises were plotted and superimposed on its photo. The new results of measurements in different areas of the reactor and at its loop installations, with emphasis on the radioactive survey of highly-contaminated samples, are presented. (authors)

Danilovich, Alexey; Ivanov, Oleg; Potapov, Victor; Semenov, Sergey; Semin, Ilya; Smirnov, Sergey; Stepanov, Vyacheslav; Volkovich, Anatoly [National Research Centre 'Kurchatov Institute', Moscow (Russian Federation)] [National Research Centre 'Kurchatov Institute', Moscow (Russian Federation)

2013-07-01T23:59:59.000Z

14

Allowable Residual Contamination Levels in soil for decommissioning the Shippingport Atomic Power Station site  

SciTech Connect (OSTI)

As part of decommissioning the Shippingport Atomic Power Station, a fundamental concern is the determination of Allowable Residual Contamination Levels (ARCL) for radionuclides in the soil at the site. The ARCL method described in this report is based on a scenario/exposure-pathway analysis and compliance with an annual dose limit for unrestricted use of the land after decommissioning. In addition to naturally occurring radionuclides and fallout from weapons testing, soil contamination could potentially come from five other sources. These include operation of the Shippingport Station as a pressurized water reactor, operations of the Shippingport Station as a light-water breeder, operation of the nearby Beaver Valley reactors, releases during decommissioning, and operation of other nearby industries, including the Bruce-Mansfield coal-fired power plants. ARCL values are presented for 29 individual radionculides and a worksheet is provided so that ARCL values can be determined for any mixture of the individual radionuclides for any annual dose limit selected. In addition, a worksheet is provided for calculating present time soil concentration value that will decay to the ARCL values after any selected period of time, such as would occur during a period of restricted access. The ARCL results are presented for both unconfined (surface) and confined (subsurface) soil contamination. The ARCL method and results described in this report provide a flexible means of determining unrestricted-use site release conditions after decommissioning the Shippingport Atomic Power Station.

Kennedy, W.E. Jr.; Napier, B.A.; Soldat, J.K.

1983-09-01T23:59:59.000Z

15

Detection of low level salmonella contamination of feed and potential infectivity for poultry  

E-Print Network [OSTI]

of MASTER OF SCIENCE May 1969 Major Subject: Veterinary Microbiology DETECTION OF LCM LEVEL SALMONELLA CONTAMINATION OF FEED AND POTENTIAL INFECTIVITY FOR POULTRY A Thesis by CHASTEEN DENNIS MURPHY Approved as to style and content by: I cl Ch rman... cultured for salmonella. On day 2 22 chicks were placed in each of four batteries and 10 into a 5th. Cloacal swabs were again made from each chick and cultured for salmonella but on this day they were put into 5 pools, one for each battery. Before...

Murphy, Chasteen Dennis

1969-01-01T23:59:59.000Z

16

Functional gene array-based analysis of microbial community structure in groundwaters with a gradient of contaminant levels  

SciTech Connect (OSTI)

To understand how contaminants affect microbial community diversity, heterogeneity, and functional structure, six groundwater monitoring wells from the Field Research Center of the U.S. Department of Energy Environmental Remediation Science Program (ERSP; Oak Ridge, TN), with a wide range of pH, nitrate, and heavy metal contamination were investigated. DNA from the groundwater community was analyzed with a functional gene array containing 2006 probes to detect genes involved in metal resistance, sulfate reduction, organic contaminant degradation, and carbon and nitrogen cycling. Microbial diversity decreased in relation to the contamination levels of the wells. Highly contaminated wells had lower gene diversity but greater signal intensity than the pristine well. The microbial composition was heterogeneous, with 17-70% overlap between different wells. Metal-resistant and metal-reducing microorganisms were detected in both contaminated and pristine wells, suggesting the potential for successful bioremediation of metal-contaminated groundwaters. In addition, results of Mantel tests and canonical correspondence analysis indicate that nitrate, sulfate, pH, uranium, and technetium have a significant (p < 0.05) effect on microbial community structure. This study provides an overall picture of microbial community structure in contaminated environments with functional gene arrays by showing that diversity and heterogeneity can vary greatly in relation to contamination.

Waldron, P.J.; Wu, L.; Van Nostrand, J.D.; Schadt, C.W.; Watson, D.B.; Jardine, P.M.; Palumbo, A.V.; Hazen, T.C.; Zhou, J.

2009-06-15T23:59:59.000Z

17

In-situ determination of radionuclide levels in facilities to be decommissioned using the allowable residual contamination level method  

SciTech Connect (OSTI)

This feasibility study resulted in verification of a direct and two alternate indirect techniques for making in-situ determinations of {sup 90}Sr and other radionuclide levels in a Hanford facility to be decommissioned that was evaluated using the Allowable Residual Contamination Level (ARCL) method. The ARCL method is used to determine the extent of decontamination that will be required before a facility can be decommissioned. A sump in the 1608F Building was chosen for the feasibility study. Hanford decommissioning personnel had previously taken 79 concrete and surface scale samples from the building to be analyzed by radiochemical analysis. The results of the radiochemical analyses compare favorably with the values derived by the in-situ methods presented in this report. Results obtained using a portable spectrometer and thermoluminescent dosimeters (TLDs) were both very close to the radiochemistry results. Surface {sup 90}Sr levels detected on the sump floor were 550 pCi/cm{sup 2} using the spectrometer system and 780 pCi/cm{sup 2} using the TLD data. This compares favorably with the levels determined by radiochemical analyses (i.e., 230 to 730 pCi/cm{sup 2}). Surface {sup 90}Sr levels detected on the sump wall ranged between 10 and 80 pCi/cm{sup 2} using the spectrometer system, compared with a conservative 200 pCi/cm{sup 2} using the TLD data. The radiochemical results ranged between 19 and 77 pCi/cm{sup 2} for the four samples taken from the wall at indeterminate locations. 17 refs., 15 figs., 2 tabs.

Arthur, R.J.; Haggard, D.L.

1989-07-01T23:59:59.000Z

18

Technical assessment of processes to enable recycling of low-level contaminated metal waste  

SciTech Connect (OSTI)

Accumulations of metal waste exhibiting low levels of radioactivity (LLCMW) have become a national burden, both financially and environmentally. Much of this metal could be considered as a resource. The Department of Energy was assigned the task of inventorying and classifying LLCMW, identifying potential applications, and applying and/or developing the technology necessary to enable recycling. One application for recycled LLCMW is high-quality canisters for permanent repository storage of high-level waste (HLW). As many as 80,000 canisters will be needed by 2035. Much of the technology needed to decontaminate LLCMW has already been developed, but no integrated process has been described, even on a pilot scale, for recycling LLCMW into HLW canisters. This report reviews practices for removal of radionuclides and for producing low carbon stainless steel. Contaminants that readily form oxides may be reduced to below de minimis levels and combined with a slag. Most of the radioactivity remaining in the ingot is concentrated in the inclusions. Radionuclides that chemically resemble the elements that comprise stainless steel can not be removed effectively. Slag compositions, current melting practices, and canister fabrication techniques were reviewed.

Reimann, G.A.

1991-10-01T23:59:59.000Z

19

Micro level study on groundwater contaminant transport modeling of industrial pollution and hydro remediation;.  

E-Print Network [OSTI]

??Water pollution is a serious problem world over, as a growing percentage of surface water resources and groundwater reserves are being contaminated due to uncontrolled… (more)

Hemamalini C G

2014-01-01T23:59:59.000Z

20

Sensitive Multi-Species Emissions Monitoring: Infrared Laser-Based Detection of Trace-Level Contaminants.  

SciTech Connect (OSTI)

This report summarizes our development of spectroscopic chemical analysis techniques and spectral modeling for trace-gas measurements of highly-regulated low-concentration species present in flue gas emissions from utility coal boilers such as HCl under conditions of high humidity. Detailed spectral modeling of the spectroscopy of HCl and other important combustion and atmospheric species such as H 2 O, CO 2 , N 2 O, NO 2 , SO 2 , and CH 4 demonstrates that IR-laser spectroscopy is a sensitive multi-component analysis strategy. Experimental measurements from techniques based on IR laser spectroscopy are presented that demonstrate sub-ppm sensitivity levels to these species. Photoacoustic infrared spectroscopy is used to detect and quantify HCl at ppm levels with extremely high signal-to-noise even under conditions of high relative humidity. Additionally, cavity ring-down IR spectroscopy is used to achieve an extremely high sensitivity to combustion trace gases in this spectral region; ppm level CH 4 is one demonstrated example. The importance of spectral resolution in the sensitivity of a trace-gas measurement is examined by spectral modeling in the mid- and near-IR, and efforts to improve measurement resolution through novel instrument development are described. While previous project reports focused on benefits and complexities of the dual-etalon cavity ring-down infrared spectrometer, here details on steps taken to implement this unique and potentially revolutionary instrument are described. This report also illustrates and critiques the general strategy of IR- laser photodetection of trace gases leading to the conclusion that mid-IR laser spectroscopy techniques provide a promising basis for further instrument development and implementation that will enable cost-effective sensitive detection of multiple key contaminant species simultaneously.

Steill, Jeffrey D

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Turbulent Flame Speeds and NOx Kinetics of HHC Fuels with Contaminants and High Dilution Levels  

SciTech Connect (OSTI)

This final report documents the technical results of the 3-year project entitled, “Turbulent Flame Speeds and NOx Kinetics of HHC Fuels with Contaminants and High Dilution Levels,” funded under the NETL of DOE. The research was conducted under six main tasks: 1) program management and planning; 2) turbulent flame speed measurements of syngas mixtures; 3) laminar flame speed measurements with diluents; 4) NOx mechanism validation experiments; 5) fundamental NOx kinetics; and 6) the effect of impurities on NOx kinetics. Experiments were performed using primary constant-volume vessels for laminar and turbulent flame speeds and shock tubes for ignition delay times and species concentrations. In addition to the existing shock- tube and flame speed facilities, a new capability in measuring turbulent flame speeds was developed under this grant. Other highlights include an improved NOx kinetics mechanism; a database on syngas blends for real fuel mixtures with and without impurities; an improved hydrogen sulfide mechanism; an improved ammonia kintics mechanism; laminar flame speed data at high pressures with water addition; and the development of an inexpensive absorption spectroscopy diagnostic for shock-tube measurements of OH time histories. The Project Results for this work can be divided into 13 major sections, which form the basis of this report. These 13 topics are divided into the five areas: 1) laminar flame speeds; 2) Nitrogen Oxide and Ammonia chemical kinetics; 3) syngas impurities chemical kinetics; 4) turbulent flame speeds; and 5) OH absorption measurements for chemical kinetics.

Peterson, Eric; Krejci, Michael; Mathieu, Olivier; Vissotski, Andrew; Ravi, Sankat; Plichta, Drew; Sikes, Travis; Levacque, Anthony; Camou, Alejandro; Aul, Christopher

2013-09-30T23:59:59.000Z

22

A Bayesian Method for Identifying Contaminated Detectors in Low-Level Alpha Spectrometers  

SciTech Connect (OSTI)

Analyses used for radiobioassay and other radiochemical tests are normally designed to meet specified quality objectives, such relative bias, precision, and minimum detectable activity (MDA). In the case of radiobioassay analyses for alpha emitting radionuclides, a major determiner of the process MDA is the instrument background. Alpha spectrometry detectors are often restricted to only a few counts over multi-day periods in order to meet required MDAs for nuclides such as plutonium-239 and americium-241. A detector background criterion is often set empirically based on experience, or frequentist or classical statistics are applied to the calculated background count necessary to meet a required MDA. An acceptance criterion for the detector background is set at the multiple of the estimated background standard deviation above the assumed mean that provides an acceptably small probability of observation if the mean and standard deviation estimate are correct. The major problem with this method is that the observed background counts used to estimate the mean, and thereby the standard deviation when a Poisson distribution is assumed, are often in the range of zero to three counts. At those expected count levels it is impossible to obtain a good estimate of the true mean from a single measurement. As an alternative, Bayesian statistical methods allow calculation of the expected detector background count distribution based on historical counts from new, uncontaminated detectors. This distribution can then be used to identify detectors showing an increased probability of contamination. The effect of varying the assumed range of background counts (i.e., the prior probability distribution) from new, uncontaminated detectors will be is discussed.

Maclellan, Jay A.; Strom, Daniel J.; Joyce, Kevin E.

2011-11-02T23:59:59.000Z

23

Radiological, physical, and chemical characterization of low-level alpha contaminated wastes stored at the Idaho National Engineering Laboratory  

SciTech Connect (OSTI)

This document provides radiological, physical, and chemical characterization data for low-level alpha-contaminated radioactive and low-level alpha-contaminated radioactive and hazardous (i.e., mixed) wastes stored at the Idaho National Engineering Laboratory and considered for treatment under the Private Sector Participation Initiative Program. Waste characterization data are provided in the form of INEL Waste Profile Sheets. These documents provide, for each content code, information on waste identification, waste description, waste storage configuration, physical/chemical waste composition, radionuclide and associated alpha activity waste characterization data, and hazardous constituents present in the waste. Information is provided for 97 waste streams which represent an estimated total volume of 25,450 m 3 corresponding to a total mass of approximately 12,000,000 kg. In addition, considerable information concerning alpha, beta, gamma, and neutron source term data specific to Rocky Flats-generated waste forms stored at the INEL are provided to assist in facility design specification.

Apel, M.L.; Becker, G.K.; Ragan, Z.K.; Frasure, J.; Raivo, B.D.; Gale, L.G.; Pace, D.P.

1994-03-01T23:59:59.000Z

24

Approach to calculating upper bounds on maximum individual doses from the use of contaminated well water following a WIPP repository breach. Report EEG-9  

SciTech Connect (OSTI)

As part of the assessment of the potential radiological consequences of the proposed Waste Isolation Pilot Plant (WIPP), this report evaluates the post-closure radiation dose commitments associated with a possible breach event which involves dissolution of the repository by groundwaters and subsequent transport of the nuclear waste through an aquifer to a well assumed to exist at a point 3 miles downstream from the repository. The concentrations of uranium and plutonium isotopes at the well are based on the nuclear waste inventory presently proposed for WIPP and basic assumptions concerning the transport of waste as well as treatment to reduce the salinity of the water. The concentrations of U-233, Pu-239, and Pu-240, all radionuclides originally emplaced as waste in the repository, would exceed current EPA drinking water limits. The concentrations of U-234, U-235, and U-236, all decay products of plutonium isotopes originally emplaced as waste, would be well below current EPA drinking water limits. The 50-year dose commitments from one year of drinking treated water contaminated with U-233 or Pu-239 and Pu-240 were found to be comparable to a one-year dose from natural background. The 50-year dose commitments from one year of drinking milk would be no more than about 1/5 the dose obtained from ingestion of treated water. These doses are considered upper bounds because of several very conservative assumptions which are discussed in the report.

Spiegler, P.

1981-09-01T23:59:59.000Z

25

Geochemical information for sites contaminated with low-level radioactive wastes: II. St. Louis Airport Storage Site  

SciTech Connect (OSTI)

The St. Louis Airport Storage Site (SLASS) became radioactively contaminated as a result of wastes that were being stored from operations to recover uranium from pitchblende ores in the 1940s and 1950s. The US Department of Energy is considering various remedial action options for the SLASS under the Formerly Utilized Site Remedial Action Program (FUSRAP). This report describes the results of geochemical investigations, carried out to support the FUSRAP activities and to aid in quantifying various remedial action options. Soil and groundwater samples from the site were characterized, and sorption ratios for uranium and radium and apparent concentration limit values for uranium were measured in soil/groundwater systems by batch contact methodology. The uranium and radium concentrations in soil samples were significantly above background near the old contaminated surface horizon (now at the 0.3/sup -/ to 0.9/sup -/m depth); the maximum values were 1566 ..mu..g/g and 101 pCi/g, respectively. Below about the 6/sup -/m depth, the concentrations appeared to be typical of those naturally present in soils of this area (3.8 +- 1.2 ..mu..g/g and 3.1 +- 0.6 pCi/g). Uranium sorption ratios showed stratigraphic trends but were generally moderate to high (100 to 1000 L/kg). The sorption isotherm suggested an apparent uranium concentration limit of about 200 mg/L. This relatively high solubility can probably be correlated with the carbonate content of the soil/groundwater systems. The lower sorption ratio values obtained from the sorption isotherm may have resulted from changes in the experimental procedure or the groundwater used. The SLASS appears to exhibit generally favorable behavior for the retardation of uranium solubilized from waste in the site. Parametric tests were conducted to estimate the sensitivity of uranium sorption and solubility to the pH and carbonate content of the system.

Seeley, F.G.; Kelmers, A.D.

1985-01-01T23:59:59.000Z

26

Geochemical information for sites contaminated with low-level radioactive wastes. III. Weldon Spring Storage Site  

SciTech Connect (OSTI)

The Weldon Spring Storage Site (WSSS), which includes both the chemical site and the quarry, became radioactively contaminated as the result of wastes that were being stored from operations to recover uranium from pitchblende ores in the 1940s and 1950s. The US Department of Energy (DOE) is considering various remedial action options for the WSSS. This report describes the results of geochemical investigations carried out at Oak Ridge National Laboratory (ORNL) to support these activities and to help quantify various remedial action options. Soil and groundwater samples were characterized, and uranium and radium sorption ratios were measured in site soil/groundwater systems by batch contact methodology. Soil samples from various locations around the raffinate pits were found to contain major amounts of silica, along with illite as the primary clay constituent. Particle sizes of the five soil samples were variable (50% distribution point ranging from 12 to 81 ..mu..m); the surface areas varied from 13 to 62 m/sup 2//g. Elemental analysis of the samples showed them to be typical of sandy clay and silty clay soils. Groundwater samples included solution from Pit 3 and well water from Well D. Anion analyses showed significant concentrations of sulfate and nitrate (>350 and >7000 mg/L, respectively) in the solution from Pit 3. These anions were also present in the well water, but in lower concentrations. Uranium sorption ratios for four of the soil samples contacted with the solution from Pit 3 were moderate to high (approx. 300 to approx. 1000 mL/g). The fifth sample had a ratio of only 12 mL/g. Radium sorption ratios for the five samples were moderate to high (approx. 600 to approx. 1000 mL/g). These values indicate that soil at the WSSS may show favorable retardation of uranium and radium in the groundwater. 13 references, 13 figures, 10 tables.

Seeley, F.G.; Kelmers, A.D.

1985-02-01T23:59:59.000Z

27

Epidemiological Investigation of Risk Factors for Microbial Contamination in Produce at the Preharvest Level  

E-Print Network [OSTI]

and vegetables at the preharvest level with L. monocytogenes, Salmonella, and E. coli O157:H7 by conducting a systematic review. The review identified and evaluated 68 published research articles which indicated soil and irrigation water as the most important...

Park, Sangshin

2013-11-15T23:59:59.000Z

28

A manual for applying the allowable residual contamination level method for decommissioning facilities on the Hanford Site  

SciTech Connect (OSTI)

This report describes the modifications that have been made to enhance the original Allowable Residual Contamination Level (ARCL) method to make it more applicable to site-specific analyses. This version considers the mixture of radionuclides present at the time of site characterization, the elapsed time after decommissioning when exposure to people could occur, and includes a calculation of the upper confidence limit of the potential dose based on sampling statistics that are developed during the site characterization efforts. The upper confidence limit of potential exposure can now be used for comparison against applicable radiation dose limits (i.e., 25 mrem/yr at Hanford). The level of confidence can be selected by the user. A wide range of exposure scenarios were evaluated; the rationale used to select the most limiting scenarios is explained. The radiation dose factors used for the inhalation and ingestion pathways were also updated to correspond with the radiation dosimetry methods utilized in the International Commission of Radiological Protection Publications 26 and 30 (ICRP 1977; 1979a,b, 1980, 1981, 1982a,b). This simplifies the calculations, since ''effective whole body'' doses are now calculated, and also brings the dosimetry methods used in the ARCL method in conformance with the rationale used by DOE in developing the 25 mrem/yr limit at Hanford. 46 refs., 21 figs., 15 tabs.

Napier, B.A.; Piepel, G.F.; Kennedy, W.E. Jr.; Schreckhise, R.G.

1988-08-01T23:59:59.000Z

29

Allowable residual contamination levels for decommissioning the 115-F and 117-F facilities at the Hanford Site  

SciTech Connect (OSTI)

This report contains the results of a study sponsored by UNC Nuclear Industries to determine Allowable Residual Contamination Levels (ARCL) for the 115-F and 117-F facilities at the Hanford Site. The purpose of this study is to provide data useful to UNC engineers in conducting safety and cost comparisons for decommissioning alternatives. The ARCL results are based on a scenario/exposure-pathway analysis and compliance with an annual dose limit for three specific modes of future use of the land and facilities. These modes of use are restricted, controlled, and unrestricted. Information on restricted and controlled use is provided to permit a full consideration of decommissioning alternatives. Procedures are presented for modifying the ARCL values to accommodate changes in the radionuclide mixture or concentrations and to determine instrument responses for various mixtures of radionuclides. Finally, a comparison is made between existing decommissioning guidance and the ARCL values calculated for unrestricted release of the 115-F and 117-F facilities. The comparison shows a good agreement.

Kennedy, W.E. Jr.; Napier, B.A.

1983-07-01T23:59:59.000Z

30

Comparative analyses of soil contaminant levels and plant species diversity at developing and disused oil well sites in Qianjiang oilfield, China  

SciTech Connect (OSTI)

Oilfield development contaminates soils and waters with crude oil, brine and heavy metals. Oil well sites are probably the most contaminated places in oilfields. During drilling and crude oil extraction from underground stores, a significant amount of oil and brine discharges into soils at oil well sites by blowouts, container spillages and pipeline ruptures. In oilfields in China, it was estimated that about 0.77 - 1.85% crude oil discharged into soils at oil well sites during oilfield development. Exposure to oil and salt contaminants could evoke toxicological effects in plants. Responses of plants to the contaminant exposure include inhibition of photosynthesis and nitrogen fixation, cessation of growth, reduced reproductive success and mortality. These harmful impacts on plants would be expected to result in remarkable loss of biodiversity. Qianjiang oilfield has been developed for about thirty-five years. Oil well sites in it have long been contaminated with oil and brine since, and plants at the well sites are rare. In the last three years however some wells have fallen into disuse. In result, a few plant species have intruded into the disuse well sites and formed new populations, and plant species diversity in these places has increased thereby. For benefit of restoration of the disuse well sites, it is interesting to know the relationships between contaminant levels and plant biodiversity. The present paper focuses the attention on comparative analyses of soil contaminations by crude oil, salt and some heavy metals and plant species diversity at developing and disuse oil well sites. 15 refs., 3 tabs.

Xiong, Z.T.; Hu, H.X.; Wang, Y.X. [Wuhan Univ., Hubei (China)] [and others] [Wuhan Univ., Hubei (China); and others

1997-04-01T23:59:59.000Z

31

Electrosorption on carbon aerogel electrodes as a means of treating low-level radioactive wastes and remediating contaminated ground water  

SciTech Connect (OSTI)

A novel separation process based upon carbon aerogel electrodes has been recently developed for the efficient removal of ionic impurities from aqueous streams. This process can be used as an electrical y- regenerated alternative to ion exchange, thereby reducing-the need for large quantities of chemical regenerants. Once spent (contaminated), these regenerants contribute to the waste that must be disposed of in landfills. The elimination of such wastes is especially beneficial in situations involving radioactive contaminants, and pump and treat processing of massive volumes of ground water. A review and analysis of potential applications will be presented.

Tran, Tri Duc; Farmer, Joseph C.; DePruneda, Jean H.; Richardson, Jeffery H.

1997-07-01T23:59:59.000Z

32

Healthy Zero Energy Buildings (HZEB) Program - Cross-Sectional Study of Contaminant Levels, Source, Strengths, and Ventilation Rates in Retail Stores  

SciTech Connect (OSTI)

This field study measured ventilation rates and indoor air quality parameters in 21 visits to retail stores in California. The data was collected to guide the development of new, science-based commercial building ventilation rate standards that balance the dual objectives of increasing energy efficiency and maintaining acceptable indoor air quality. Data collection occurred between September 2011 and March 2013. Three types of stores participated in this study: grocery stores, furniture/hardware stores, and apparel stores. Ventilation rates and indoor air contaminant concentrations were measured on a weekday, typically between 9 am and 6 pm. Ventilation rates measured using a tracer gas decay method exceeded the minimum requirement of California’s Title 24 Standard in all but one store. Even though there was adequate ventilation according to Title 24, concentrations of formaldehyde, acetaldehyde, and acrolein exceeded the most stringent chronic health guidelines. Other indoor air contaminants measured included carbon dioxide (CO{sub 2}), carbon monoxide (CO), ozone (O{sub 3}), and particulate matter (PM). Concentrations of CO{sub 2} were kept low by adequate ventilation, and were assumed low also because the sampling occurred on a weekday when retail stores were less busy. CO concentrations were also low. The indoor-outdoor ratios of O{sub 3} showed that the first-order loss rate may vary by store trade types and also by ventilation mode (mechanical versus natural). Analysis of fine and ultrafine PM measurements showed that a substantial portion of the particle mass in grocery stores with cooking-related emissions was in particles less than 0.3 ?m. Stores without cooking as an indoor source had PM size distributions that were more similar indoors and outdoors. The whole-building emission rates of volatile organic compounds (VOCs) and PM were estimated from the measured ventilation rates and indoor and outdoor contaminant concentrations. Mass balance models were then used to determine the ventilation rates, filtration strategies, or source reductions needed to maintain indoor contaminant concentrations below reference levels. Several scenarios of potential concern were considered: (i) formaldehyde levels in furniture/hardware stores, (ii) contaminants associated with cooking (e.g., PM, acrolein, and acetaldehyde) in grocery stores, and (iii) outdoor contaminants (e.g., PM and O{sub 3}) impacting stores that use natural ventilation. Estimated formaldehyde emission rates suggest that retail stores would need to ventilate at levels far exceeding the current Title 24 requirement to lower indoor concentrations below California’s stringent formaldehyde reference level. Given the high costs of providing ventilation but only modest chronic health benefit is expected, effective source control is an attractive alternative, as demonstrated by some retail stores in this study. Predictions showed that grocery stores need MERV 13 air filters, instead of MERV 8 filters that are more commonly used, to maintain indoor PM at levels that meet the chronic health standards for PM. Exposure to acrolein is a potential health concern in grocery stores, and should be addressed by increasing the use of kitchen range hoods or improving their contaminant removal efficiency. In stores that rely on natural ventilation, indoor PM can be a health concern if the stores are located in areas with high outdoor PM. This concern may be addressed by switching to mechanical ventilation when the outdoor air quality is poor, while continuing natural ventilation when outdoor air quality is good.

Chan, Wanyu R.; Sidheswaran, Meera; Cohn, Sebastian; Sullivan, Douglas P.; Fisk, William

2014-02-01T23:59:59.000Z

33

Waste and cost reduction using dual wall reverse circulation drilling with multi-level groundwater sampling for contaminant plume delineation  

SciTech Connect (OSTI)

This paper describes the drilling and sampling methods used to delineate a groundwater contaminant plume at the Paducah Gaseous Diffusion Plant (PGDP) during the Groundwater Monitoring IV characterization. The project was unique in that it relied upon dual wall reverse circulation drilling instead of the traditional hollow stem auger method. The Groundwater Monitoring program sought to characterize the boundaries, both vertically and horizontally, of the northeast plume which contains both {sup 99}Tc and trichloroethene. This paper discusses the strengths and weaknesses of the drilling method used by investigators.

Smuin, D.R.

1995-12-01T23:59:59.000Z

34

Declining metal levels at Foundry Cove (Hudson River, New York): Response to localized dredging of contaminated sediments  

E-Print Network [OSTI]

a well-recognized case of heavy metal pollution at Foundry Cove (FC), Hudson River, New York. This tidal River. Ã? 2007 Elsevier Ltd. All rights reserved. Keywords: River pollution; Cadmium; Metal removalDeclining metal levels at Foundry Cove (Hudson River, New York): Response to localized dredging

Levinton, Jeffrey

35

Bioremediation of contaminated groundwater  

DOE Patents [OSTI]

An apparatus and method are described for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid is selected to stimulate the growth and reproduction of indigenous subsurface microorganisms that are capable of degrading the contaminants. An oxygenated fluid is selected to create a generally aerobic environment for these microorganisms to degrade the contaminants, leaving only pockets that are anaerobic. The nutrient fluid is injected periodically while the oxygenated fluid is injected continuously and both are extracted so that both are drawn across the plume. The nutrient fluid stimulates microbial colony growth. Withholding it periodically forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is reduced to an acceptable, preselected level. The nutrient fluid can be methane and the oxygenated fluid air for stimulating production of methanotrophs to break down chlorohydrocarbons, especially trichloroethylene (TCE) and tetrachloroethylene. 3 figures.

Hazen, T.C.; Fliermans, C.B.

1995-01-24T23:59:59.000Z

36

Bioremediation of contaminated groundwater  

DOE Patents [OSTI]

An apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid is selected to stimulate the growth and reproduction of indigenous subsurface microorganisms that are capable of degrading the contaminants; an oxygenated fluid is selected to create a generally aerobic environment for these microorganisms to degrade the contaminants, leaving only pockets that are anaerobic. The nutrient fluid is injected periodically while the oxygenated fluid is injected continuously and both are extracted so that both are drawn across the plume. The nutrient fluid stimulates microbial colony growth; withholding it periodicially forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is reduced to an acceptable, preselected level. The nutrient fluid can be methane and the oxygenated fluid air for stimulating production of methanotrophs to break down chlorohydrocarbons, especially trichloroethylene (TCE) and tetrachloroethylene.

Hazen, Terry C. (Augusta, GA); Fliermans, Carl B. (Augusta, GA)

1995-01-01T23:59:59.000Z

37

MELE: Maximum Entropy Leuven Estimators  

E-Print Network [OSTI]

of the Generalized Maximum Entropy Estimator of the Generaland Douglas Miller, Maximum Entropy Econometrics, Wiley andCalifornia Davis MELE: Maximum Entropy Leuven Estimators by

Paris, Quirino

2001-01-01T23:59:59.000Z

38

Maximum Entropy Correlated Equilibria  

E-Print Network [OSTI]

We study maximum entropy correlated equilibria in (multi-player)games and provide two gradient-based algorithms that are guaranteedto converge to such equilibria. Although we do not provideconvergence rates for these ...

Ortiz, Luis E.

2006-03-20T23:59:59.000Z

39

Predicting Fate and Transport of Contaminants in the Vadose Zone using a Soil Screening Model  

SciTech Connect (OSTI)

Soil Screening Levels (SSLs) are threshold concentrations below which there is no concern for the migration of residual soil contaminants to the aquifer above maximum contaminant levels (MCLs). At sites where contaminant concentrations exceed SSLs, further study maybe warranted under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). SSLs are based upon simplified fate and transport assumptions, but the guidance allows the flexibility to develop a detailed modeling approach that accounts for complex site variables such as degradation and thickness of the vadose zone. The distinct advantage of the detailed modeling is that individual sites may calculate a less restrictive, but still protective SSL. A Multi-Layer Vadose Zone Contaminant Migration Model [VZCOMML(C)] was developed at the Savannah River Site to allay the higher costs of detailed modeling and achieve a higher clean-up level. The software model is faster, simpler, and less expensive to us e than other commercially available codes.

Rucker, G.

2002-08-14T23:59:59.000Z

40

Milk is a common ingredient in many fried foods. Allergen cross contact can occur through the use of shared frying oil. Analytical methods are needed to determine the level of protein contamination in re-used oil. This study  

E-Print Network [OSTI]

the use of shared frying oil. Analytical methods are needed to determine the level of protein contamination in re-used oil. This study evaluated the performance of four ELISA test kits in comparison with a total protein assay for detection of milk protein residues in spiked oils that have been subjected

Heller, Barbara

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Dual wall reverse circulation drilling with multi-level groundwater sampling for groundwater contaminant plume delineation at Paducah Gaseous Diffusion Plant, Paducah, Kentucky  

SciTech Connect (OSTI)

Dual wall reverse circulation (DWRC) drilling was used to drill 48 borings during a groundwater contaminant investigation at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky. This method was selected as an alternative to conventional hollow stem auger drilling for a number of reasons, including the expectation of minimizing waste, increasing the drilling rate, and reducing the potential for cross contamination of aquifers. Groundwater samples were collected from several water-bearing zones during drilling of each borehole. The samples were analyzed for volatile organic compounds using a field gas chromatograph. This approach allowed the investigation to be directed using near-real-time data. Use of downhole geophysical logging, in conjunction with lithologic descriptions of borehole cuttings, resulted in excellent correlation of the geology in the vicinity of the contaminant plume. The total volume of cuttings generated using the DWRC drilling method was less than half of what would have been produced by hollow stem augering; however, the cuttings were recovered in slurry form and had to be dewatered prior to disposal. The drilling rate was very rapid, often approaching 10 ft/min; however, frequent breaks to perform groundwater sampling resulted in an average drilling rate of < 1 ft/min. The time required for groundwater sampling could be shortened by changing the sampling methodology. Analytical results indicated that the drilling method successfully isolated the various water bearing zones and no cross contamination resulted from the investigation.

Smuin, D.R.; Morti, E.E.; Zutman, J.L.; Pickering, D.A.

1995-08-01T23:59:59.000Z

42

Decreasing aqueous mercury concentrations to achieve safe levels in fish: examining the water-fish relationship in two point-source contaminated streams  

SciTech Connect (OSTI)

East Fork Poplar Creek (EFPC) and White Oak Creek (WOC) are two mercury-contaminated streams located on the Department of Energy s Oak Ridge Reservation in east Tennessee. East Fork Poplar Creek is the larger and more contaminated of the two, with average aqueous mercury (Hg) concentrations exceeding those in reference streams by several hundred-fold. Remedial actions over the past 20 years have decreased aqueous Hg concentrations in EFPC by 85 %. Fish fillet concentrations, however, have not responded to this decrease in aqueous Hg and remain above the U.S. Environmental Protection Agency s ambient water quality criterion (AWQC) of 0.3 mg/kg. The lack of correlation between aqueous and fish tissue Hg concentrations in this creek has led to questions regarding the usefulness of target aqueous Hg concentrations and strategies for future remediation efforts. White Oak Creek has a similar contamination history but aqueous Hg concentrations in WOC are an order of magnitude lower than in EFPC. Despite the lower aqueous Hg concentrations, fish fillet concentrations in WOC have also been above the AWQC, making the most recent aqueous Hg target of 200 ng/L in EFPC seem unlikely to result in an effective decrease in fillet Hg concentrations. Recent monitoring efforts in WOC, however, suggest an aqueous total Hg threshold above which Hg bioaccumulation in fish may not respond. This new information could be useful in guiding remedial actions in EFPC and in other point-source contaminated streams.

Mathews, Teresa J [ORNL; Southworth, George R [ORNL; Peterson, Mark J [ORNL; Roy, W Kelly [ORNL; Ketelle, Richard H [ORNL; Valentine, Charles S [ORNL; Gregory, Scott M [ORNL

2013-01-01T23:59:59.000Z

43

Process for treating waste water having low concentrations of metallic contaminants  

DOE Patents [OSTI]

A process for treating waste water having a low level of metallic contaminants by reducing the toxicity level of metallic contaminants to an acceptable level and subsequently discharging the treated waste water into the environment without removing the treated contaminants.

Looney, Brian B; Millings, Margaret R; Nichols, Ralph L; Payne, William L

2014-12-16T23:59:59.000Z

44

TRACING THE CONTAMINANT HISTORY OF AN URBAN WATERSHED THROUGH AN EXAMINATION OF AQUATIC  

E-Print Network [OSTI]

TRACING THE CONTAMINANT HISTORY OF AN URBAN WATERSHED THROUGH AN EXAMINATION OF AQUATIC SEDIMENTS. A smaller organic contaminant database indicates sediment PAH levels exceed probable effect level criteria

45

Mechanisms of contaminant migration from grouted waste  

SciTech Connect (OSTI)

Low-level radioactive decontaminated salt solution is generated at the Savannah River Site (SRS) from the In-Tank Precipitation process. The solution is mixed with cement, slag, and fly ash, to form a grout, termed ``Saltstone``, that will be disposed in concrete vaults at the Saltstone Disposal Facility (SDF) [1]. Of the contaminants in the Saltstone, the greatest concern to SRS is the potential release of nitrate to the groundwater because of the high initial nitrate concentration (0.25 g/cm{sup 3}) in the Saltstone and the low Safe Drinking Water Act (SDWA) maximum contaminant level (MCL) of 44 mg/L. The SDF is designed to allow a slow, controlled release over thousands of years. This paper addresses a modeling study of nitrate migration from intact non-degraded concrete vaults in the unsaturated zone for the Radiological Performance Assessment (PA) of the SRS Saltstone Disposal Facility [3]. The PA addresses the performance requirements mandated by DOE Order 5820.2A [4].

Magnuson, S.O. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Yu, A.D. [Westinghouse Savannah River Co., Aiken, SC (United States)

1992-12-31T23:59:59.000Z

46

Single ion heat engine with maximum efficiency at maximum power  

E-Print Network [OSTI]

We propose an experimental scheme to realize a nano heat engine with a single ion. An Otto cycle may be implemented by confining the ion in a linear Paul trap with tapered geometry and coupling it to engineered laser reservoirs. The quantum efficiency at maximum power is analytically determined in various regimes. Moreover, Monte Carlo simulations of the engine are performed that demonstrate its feasibility and its ability to operate at maximum efficiency of 30% under realistic conditions.

Obinna Abah; Johannes Rossnagel; Georg Jacob; Sebastian Deffner; Ferdinand Schmidt-Kaler; Kilian Singer; Eric Lutz

2012-05-07T23:59:59.000Z

47

Subsurface Contamination Control  

SciTech Connect (OSTI)

There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the subsurface repository; (2) provides a table of derived LRCL for nuclides of radiological importance; (3) Provides an as low as is reasonably achievable (ALARA) evaluation of the derived LRCL by comparing potential onsite and offsite doses to documented ALARA requirements; (4) Provides a method for estimating potential releases from a defective WP; (5) Provides an evaluation of potential radioactive releases from a defective WP that may become airborne and result in contamination of the subsurface facility; and (6) Provides a preliminary analysis of the detectability of a potential WP leak to support the design of an airborne release monitoring system.

Y. Yuan

2001-11-16T23:59:59.000Z

48

Subsurface Contamination Control  

SciTech Connect (OSTI)

There are two objectives of this report, ''Subsurface Contamination Control''. The first is to provide a technical basis for recommending limiting radioactive contamination levels (LRCL) on the external surfaces of waste packages (WP) for acceptance into the subsurface repository. The second is to provide an evaluation of the magnitude of potential releases from a defective WP and the detectability of the released contents. The technical basis for deriving LRCL has been established in ''Retrieval Equipment and Strategy for Wp on Pallet'' (CRWMS M and O 2000g, 6.3.1). This report updates the derivation by incorporating the latest design information of the subsurface repository for site recommendation. The derived LRCL on the external surface of WPs, therefore, supercede that described in CRWMS M and O 2000g. The derived LRCL represent the average concentrations of contamination on the external surfaces of each WP that must not be exceeded before the WP is to be transported to the subsurface facility for emplacement. The evaluation of potential releases is necessary to control the potential contamination of the subsurface repository and to detect prematurely failed WPs. The detection of failed WPs is required in order to provide reasonable assurance that the integrity of each WP is intact prior to MGR closure. An emplaced WP may become breached due to manufacturing defects or improper weld combined with failure to detect the defect, by corrosion, or by mechanical penetration due to accidents or rockfall conditions. The breached WP may release its gaseous and volatile radionuclide content to the subsurface environment and result in contaminating the subsurface facility. The scope of this analysis is limited to radioactive contaminants resulting from breached WPs during the preclosure period of the subsurface repository. This report: (1) documents a method for deriving LRCL on the external surfaces of WP for acceptance into the subsurface repository; (2) provides a table of derived LRCL for nuclides of radiological importance; (3) Provides an as low as is reasonably achievable (ALARA) evaluation of the derived LRCL by comparing potential onsite and offsite doses to documented ALARA requirements; (4) Provides a method for estimating potential releases from a defective WP; (5) Provides an evaluation of potential radioactive releases from a defective WP that may become airborne and result in contamination of the subsurface facility; and (6) Provides a preliminary analysis of the detectability of a potential WP leak to support the design of an airborne release monitoring system.

Y. Yuan

2001-12-12T23:59:59.000Z

49

Tracer-level radioactive pilot-scale test of in situ vitrification for the stabilization of contaminated soil sites at ORNL  

SciTech Connect (OSTI)

A field demonstration of in situ vitrification (ISV) was completed in May 1991, and produced approximately 12 Mg of melted earthen materials containing 12.7 mCi of radioactivity within 500 g of sludge in amodel of an old seepage trench waste disposal unit. Past waste disposal operations at Oak Ridge National Laboratory have left several contaminated seepage sites. In planning for remediation of such sites, ISV technology has been identified as a leading candidate because of the high risks associated with any retrieval option and because of the usual high quality of vitreous waste form. Major isotopes placed in the test trench were {sup 137}Cs and {sup 90}Sr, with lesser amounts of {sup 6O}Co, {sup 241}Am, and {sup 239,240}Pu. A total of 29 MWh of electrical power was delivered to the ground over a 5-day period producing a melt depth of 8.5 ft. During melting, 2.4% of the {sup 137}Cs volatilized from the melt into an off-gas containment hood and was captured quantitatively on a high efficiency particulate air filter. No volatilization of {sup 90}Sr, {sup 241}Am, or {sup 239,240}Pu was detected and > 99.993% retention of these isotopes in the melt was estimated. The use of added rare earth tracers (Ce, La, and Nd), as surrogates for transuranic isotopes, led to estimated melt retentions of >99.9995% during the test. The molten material, composed of the native soil and dolomitic limestone used for filling the test trench, reached a processing temperature of 1500{degrees}C. Standardized leaching procedures using Product Consistency Testing indicated that the ISV product has excellent characteristics relative to other vitreous nuclear waste forms.

Spalding, B.P.; Jacobs, G.K.; Naney, M.T. [Oak Ridge National Lab., TN (United States); Dunbar, N.W. [New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States); Tixier, J.S.; Powell, T.D. [Pacific Northwest Lab., Richland, WA (United States)

1992-11-01T23:59:59.000Z

50

Tracer-level radioactive pilot-scale test of in situ vitrification for the stabilization of contaminated soil sites at ORNL  

SciTech Connect (OSTI)

A field demonstration of in situ vitrification (ISV) was completed in May 1991, and produced approximately 12 Mg of melted earthen materials containing 12.7 mCi of radioactivity within 500 g of sludge in amodel of an old seepage trench waste disposal unit. Past waste disposal operations at Oak Ridge National Laboratory have left several contaminated seepage sites. In planning for remediation of such sites, ISV technology has been identified as a leading candidate because of the high risks associated with any retrieval option and because of the usual high quality of vitreous waste form. Major isotopes placed in the test trench were [sup 137]Cs and [sup 90]Sr, with lesser amounts of [sup 6O]Co, [sup 241]Am, and [sup 239,240]Pu. A total of 29 MWh of electrical power was delivered to the ground over a 5-day period producing a melt depth of 8.5 ft. During melting, 2.4% of the [sup 137]Cs volatilized from the melt into an off-gas containment hood and was captured quantitatively on a high efficiency particulate air filter. No volatilization of [sup 90]Sr, [sup 241]Am, or [sup 239,240]Pu was detected and > 99.993% retention of these isotopes in the melt was estimated. The use of added rare earth tracers (Ce, La, and Nd), as surrogates for transuranic isotopes, led to estimated melt retentions of >99.9995% during the test. The molten material, composed of the native soil and dolomitic limestone used for filling the test trench, reached a processing temperature of 1500[degrees]C. Standardized leaching procedures using Product Consistency Testing indicated that the ISV product has excellent characteristics relative to other vitreous nuclear waste forms.

Spalding, B.P.; Jacobs, G.K.; Naney, M.T. (Oak Ridge National Lab., TN (United States)); Dunbar, N.W. (New Mexico Bureau of Mines and Mineral Resources, Socorro, NM (United States)); Tixier, J.S.; Powell, T.D. (Pacific Northwest Lab., Richland, WA (United States))

1992-11-01T23:59:59.000Z

51

Protecting Our Water: Tracking Sources of Bacterial Contamination Numerous surface waterbodies in Texas are classified as having high levels of fecal coliform bacteria, an indicator of fecal pollution.  

E-Print Network [OSTI]

in Texas are classified as having high levels of fecal coliform bacteria, an indicator of fecal pollution. coli and other fecal coliform bacteria do not provide information on whether the source of pollution of pollution need to be identified to implement effective pollution control strategies to improve water quality

52

Manganese peroxidase mRNA and enzyme activity levels during bioremediation of polycyclic aromatic hydrocarbon-contaminated soil with Phanerochaete chrysosporium  

SciTech Connect (OSTI)

mRNA extraction from soil and quantitation by competitive reverse transcription-PCR were combined to study the expression of three manganese peroxidase (MnP) genes during removal of polycyclic aromatic hydrocarbons from cultures of Phanerochaete chrysosporium grown in presterilized soil. Periods of high mnp transcript levels and extractable MnP enzyme activity were temporally correlated, although separated by a short (1- to 2-day) lag period. This time frame also coincided with maximal rates of fluorene oxidation and chrysene disappearance in soil cultures, supporting the hypothesis that high ionization potential polycyclic aromatic hydrocarbons are oxidized in soil via MnP-dependent mechanisms. The patterns of transcript abundance over time in soil-grown P. chrysosporium were similar for all three of the mnp mRNAs studied, indicating that transcription of this gene family may be coordinately regulated under these growth conditions. 47 refs., 6 figs., 1 tab.

Bogan, B.W. [Univ. of Wisconsin, Madison, WI (United States); Schoenike, B.; Lamar, R.T.; Cullen, D. [Forest Service Forest Products Lab., Madison, WI (United States)

1996-07-01T23:59:59.000Z

53

Maximum containment : the most controversial labs in the world  

E-Print Network [OSTI]

In 2002, following the September 11th attacks and the anthrax letters, the United States allocated money to build two maximum containment biology labs. Called Biosafety Level 4 (BSL-4) facilities, these labs were built to ...

Bruzek, Alison K. (Allison Kim)

2013-01-01T23:59:59.000Z

54

Distribution of polychlorinated biphenyls and organochlorine pesticides in human breast milk from various locations in Tunisia: Levels of contamination, influencing factors, and infant risk assessment  

SciTech Connect (OSTI)

The concentrations of dichlorodiphenytrichloroethane and its metabolites (DDTs), hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), dieldrin, and 20 polychlorinated biphenyls (PCBs) were determined in 237 human breast milk samples collected from 12 locations in Tunisia. Gas chromatography with electron capture detector (GC-ECD) was used to identify and quantify residue levels on a lipid basis of organochlorine compounds (OCs). The predominant OCs in human breast milk were PCBs, p,p'-DDE, p,p'-DDT, HCHs, and HCB. Concentrations of DDTs in human breast milk from rural areas were significantly higher than those from urban locations (p<0.05). With regard to PCBs, we observed the predominance of mid-chlorinated congeners due to the presence of PCBs with high K{sub ow} such as PCB 153, 138, and 180. Positive correlations were found between concentrations of OCs in human breast milk and age of mothers and number of parities, suggesting the influence of such factors on OC burdens in lactating mothers. The comparison of daily intakes of PCBs, DDTs, HCHs, and HCB to infants through human breast milk with guidelines proposed by WHO and Health Canada shows that some individuals accumulated OCs in breast milk close to or higher than these guidelines.

Ennaceur, S. [Laboratory of Environmental Analytical Chemistry (05/UR/12-03), Faculty of Sciences, Bizerte, 7021 Zarzouna (Tunisia)], E-mail: ennaceurs@yahoo.fr; Gandoura, N. [Service of Pediatrics, Regional Hospital of Bizerte, Bizerte (Tunisia); Driss, M.R. [Laboratory of Environmental Analytical Chemistry (05/UR/12-03), Faculty of Sciences, Bizerte, 7021 Zarzouna (Tunisia)

2008-09-15T23:59:59.000Z

55

Estimating a mixed strategy employing maximum entropy  

E-Print Network [OSTI]

MIXED STRATEGY EMPLOYING MAXIMUM ENTROPY by Amos Golan LarryMixed Strategy Employing Maximum Entropy Amos Golan Larry S.Abstract Generalized maximum entropy may be used to estimate

Golan, Amos; Karp, Larry; Perloff, Jeffrey M.

1996-01-01T23:59:59.000Z

56

MaximumLetThrough.PDF  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping the Nanoscale LandscapeImportsBG NorthMauro9 Maximum Let-Through

57

Filtering Additive Measurement Noise with Maximum Entropy in the Mean  

E-Print Network [OSTI]

The purpose of this note is to show how the method of maximum entropy in the mean (MEM) may be used to improve parametric estimation when the measurements are corrupted by large level of noise. The method is developed in the context on a concrete example: that of estimation of the parameter in an exponential distribution. We compare the performance of our method with the bayesian and maximum likelihood approaches.

Henryk Gzyl; Enrique ter Horst

2007-09-04T23:59:59.000Z

58

Interim measure conceptual design for remediation of source area contamination at Agra, Kansas.  

SciTech Connect (OSTI)

This document presents a conceptual design for the implementation of a non-emergency interim measure (IM) at the site of the grain storage facility formerly operated by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) in Agra, Kansas. The IM is recommended to mitigate localized carbon tetrachloride contamination in the vadose zone soils at the former CCC/USDA facility and eliminate ongoing soil-to-groundwater contamination. The objectives of this IM conceptual design report include the following: 1. Obtain written acknowledgement from the Kansas Department of Health and the Environment (KDHE) that remediation on the former CCC/USDA property is required. 2. Provide information (IM description, justification for the IM, and project schedule) that the KDHE can include in a pending fact sheet. 3. Obtain KDHE approval for the IM conceptual design, so that the CCC/USDA can initiate a formal request for access to the privately owned property and proceed with preparation of a remedial design plan (RDP). Investigations conducted on behalf of the CCC/USDA by Argonne National Laboratory (Argonne 2006) have demonstrated that soil and groundwater at the Agra site are contaminated with carbon tetrachloride. The levels in groundwater exceed the Kansas Tier 2 Risk-Based Screening Level (RBSL) and the U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) of 5.0 {micro}g/L for this compound. The soil and groundwater contamination identified at the former CCC/USDA facility currently poses no unacceptable health risks.

LaFreniere, L. M.; Environmental Science Division

2007-07-31T23:59:59.000Z

59

A petroleum contaminated soil bioremediation facility  

SciTech Connect (OSTI)

The amount of petroleum contaminated soil (PCS) at the Savannah River site (SRS) that has been identified, excavated and is currently in storage has increased several fold during the last few years. Several factors have contributed to this problem: (1) South Carolina Department of Health ad Environmental control (SCDHEC) lowered the sanitary landfill maximum concentration for total petroleum hydrocarbons (TPH) in the soil from 500 to 100 parts per million (ppm), (2) removal and replacement of underground storage tanks at several sites, (3) most recently SCDHEC disallowed aeration for treatment of contaminated soil, and (4) discovery of several very large contaminated areas of soil associated with leaking underground storage tanks (LUST), leaking pipes, disposal areas, and spills. Thus, SRS has an urgent need to remediate large quantities of contaminated soil that are currently stockpiled and the anticipated contaminated soils to be generated from accidental spills. As long as we utilize petroleum based compounds at the site, we will continue to generate contaminated soil that will require remediation.

Lombard, K.; Hazen, T.

1994-06-01T23:59:59.000Z

60

A Lesson Learned on Determination of Radionuclides on Metal Surface Fixed Contamination  

SciTech Connect (OSTI)

A Measurement of fixed surface contamination required to determine classification as low-level or as transuranic waste.

MEZNARICH, H.K.

2000-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Total effective dose equivalent associated with fixed uranium surface contamination  

SciTech Connect (OSTI)

This report provides the technical basis for establishing a uranium fixed-contamination action level, a fixed uranium surface contamination level exceeding the total radioactivity values of Appendix D of Title 10, Code of Federal Regulations, part 835 (10CFR835), but below which the monitoring, posting, and control requirements for Radiological Areas are not required for the area of the contamination. An area of fixed uranium contamination between 1,000 dpm/100 cm{sup 2} and that level corresponding to an annual total effective dose equivalent (TEDE) of 100 mrem requires only routine monitoring, posting to alert personnel of the contamination, and administrative control. The more extensive requirements for monitoring, posting, and control designated by 10CFR835 for Radiological Areas do not have to be applied for these intermediate fixed-contamination levels.

Bogard, J.S.; Hamm, R.N.; Ashley, J.C.; Turner, J.E.; England, C.A.; Swenson, D.E.; Brown, K.S.

1997-04-01T23:59:59.000Z

62

Maximum entropy principal for transportation  

SciTech Connect (OSTI)

In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.

Bilich, F. [University of Brasilia (Brazil); Da Silva, R. [National Research Council (Brazil)

2008-11-06T23:59:59.000Z

63

Contamination analysis unit  

DOE Patents [OSTI]

The portable Contamination Analysis Unit (CAU) measures trace quantifies of surface contamination in real time. The detector head of the portable contamination analysis unit has an opening with an O-ring seal, one or more vacuum valves and a small mass spectrometer. With the valve closed, the mass spectrometer is evacuated with one or more pumps. The O-ring seal is placed against a surface to be tested and the vacuum valve is opened. Data is collected from the mass spectrometer and a portable computer provides contamination analysis. The CAU can be used to decontaminate and decommission hazardous and radioactive surface by measuring residual hazardous surface contamination, such as tritium and trace organics It provides surface contamination data for research and development applications as well as real-time process control feedback for industrial cleaning operations and can be used to determine the readiness of a surface to accept bonding or coatings.

Gregg, Hugh R. (Livermore, CA); Meltzer, Michael P. (Livermore, CA)

1996-01-01T23:59:59.000Z

64

Contamination analysis unit  

DOE Patents [OSTI]

The portable Contamination Analysis Unit (CAU) measures trace quantities of surface contamination in real time. The detector head of the portable contamination analysis unit has an opening with an O-ring seal, one or more vacuum valves and a small mass spectrometer. With the valve closed, the mass spectrometer is evacuated with one or more pumps. The O-ring seal is placed against a surface to be tested and the vacuum valve is opened. Data is collected from the mass spectrometer and a portable computer provides contamination analysis. The CAU can be used to decontaminate and decommission hazardous and radioactive surfaces by measuring residual hazardous surface contamination, such as tritium and trace organics. It provides surface contamination data for research and development applications as well as real-time process control feedback for industrial cleaning operations and can be used to determine the readiness of a surface to accept bonding or coatings. 1 fig.

Gregg, H.R.; Meltzer, M.P.

1996-05-28T23:59:59.000Z

65

Addendum to the East Tennessee Technology Park Site-Wide Residual Contamination Remedial Investigation Work Plan Oak Ridge, Tennessee  

SciTech Connect (OSTI)

The East Tennessee Technology Park Site-Wide Residual Contamination Remedial Investigation Work Plan (DOE 2004) describes the planned fieldwork to support the remedial investigation (RI) for residual contamination at the East Tennessee Technology Park (ETTP) not addressed in previous Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) decisions. This Addendum describes activities that will be conducted to gather additional information in Zone 1 of the ETTP for groundwater, surface water, and sediments. This Addendum has been developed from agreements reached in meetings held on June 23, 2010, August 25, 2010, October 13, 2010, November 13, 2010, December 1, 2010, and January 13, 2011, with representatives of the U. S. Department of Energy (DOE), U. S. Environmental Protection Agency (EPA), and Tennessee Department of Environment and Conservation (TDEC). Based on historical to recent groundwater data for ETTP and the previously completed Sitewide Remedial Investigation for the ETTP (DOE 2007a), the following six areas of concern have been identified that exhibit groundwater contamination downgradient of these areas above state of Tennessee and EPA drinking water maximum contaminant levels (MCLs): (1) K-720 Fly Ash Pile, (2) K-770 Scrap Yard, (3) Duct Island, (4) K-1085 Firehouse Burn/J.A. Jones Maintenance Area, (5) Contractor's Spoil Area (CSA), and (6) Former K-1070-A Burial Ground. The paper presents a brief summary of the history of the areas, the general conceptual models for the observed groundwater contamination, and the data gaps identified.

SAIC

2011-04-01T23:59:59.000Z

66

Review of soil contamination guidance  

SciTech Connect (OSTI)

A review of existing and proposed radioactive soil contamination standards and guidance was conducted for United Nuclear Corporation (UNC), Office of Surplus Facilities Management. Information was obtained from both government agencies and other sources during a literature survey. The more applicable standards were reviewed, evaluated, and summarized. Information pertaining to soil contamination for both facility operation and facility decommissioning was obtained from a variety of sources. These sources included: the Code of Federal Regulations, regulatory guides, the Federal Register, topical reports written by various government agencies, topical reports written by national laboratories, and publications from the American National Standards Institute (ANSI). It was difficult to directly compare the standards and guidance obtained from these sources since each was intended for a specific situation and different units or bases were used. However, most of the information reviewed was consistent with the philosophy of maintaining exposures at levels as low as reasonably achievable (ALARA).

Mueller, M.A.; Kennedy, W.E. Jr.; Soldat, J.K.

1981-08-01T23:59:59.000Z

67

Etiology and Management of Aflatoxin Contamination  

E-Print Network [OSTI]

pets, is of both regulatory and economic concern. Deaths of pets due to aflatox- ins in U.S. pet foods used as foods or feeds. In crops intended for human consumption, maximum permitted aflatoxin levels

Cotty, Peter J.

68

Contamination Control Techniques  

SciTech Connect (OSTI)

Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.

EBY, J.L.

2000-05-16T23:59:59.000Z

69

Bioremediation of contaminated groundwater  

DOE Patents [OSTI]

Disclosed is an apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid (NF) is selected to simulated the growth and reproduction of indigenous subsurface microorganisms capable of degrading the contaminants; an oxygenated fluid (OF) is selected to create an aerobic environment with anaerobic pockets. NF is injected periodically while OF is injected continuously and both are extracted so that both are drawn across the plume. NF stimulates microbial colony growth; withholding it periodically forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is acceptable. NF can be methane and OF be air, for stimulating production of methanotrophs to break down chlorohydrocarbons, especially TCE and tetrachloroethylene.

Hazen, T.C.; Fliermans, C.B.

1994-01-01T23:59:59.000Z

70

Subsurface contaminants focus area  

SciTech Connect (OSTI)

The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

NONE

1996-08-01T23:59:59.000Z

71

Los Alamos racquetball contamination incident  

SciTech Connect (OSTI)

Several employees of the Los Alamos Plutonium Facility were found to have low levels of radioactivity on their hands and clothing when they arrived for work one morning. The initial concern was that the stringent contamination or material controls at the facility had failed, and that one or more of the employees had either accidentally or intentionally removed plutonium from the Laboratory premises. Fortunately, however, an investigation revealed that the source of the radioactivity was radon daughters electrostatically collected upon the surface of the racquetball and transferred by physical contact to the employees during an early morning racquetball game. This paper describes the events leading to the discovery of this phenomenon. 1 figure.

McAtee, J.L.; Stafford, R.G.; Dowdy, E.J.; Prestwood, R.J.

1985-01-01T23:59:59.000Z

72

Modeling for Airborne Contamination  

SciTech Connect (OSTI)

The objective of Modeling for Airborne Contamination (referred to from now on as ''this report'') is to provide a documented methodology, along with supporting information, for estimating the release, transport, and assessment of dose to workers from airborne radioactive contaminants within the Monitored Geologic Repository (MGR) subsurface during the pre-closure period. Specifically, this report provides engineers and scientists with methodologies for estimating how concentrations of contaminants might be distributed in the air and on the drift surfaces if released from waste packages inside the repository. This report also provides dose conversion factors for inhalation, air submersion, and ground exposure pathways used to derive doses to potentially exposed subsurface workers. The scope of this report is limited to radiological contaminants (particulate, volatile and gaseous) resulting from waste package leaks (if any) and surface contamination and their transport processes. Neutron activation of air, dust in the air and the rock walls of the drift during the preclosure time is not considered within the scope of this report. Any neutrons causing such activation are not themselves considered to be ''contaminants'' released from the waste package. This report: (1) Documents mathematical models and model parameters for evaluating airborne contaminant transport within the MGR subsurface; and (2) Provides tables of dose conversion factors for inhalation, air submersion, and ground exposure pathways for important radionuclides. The dose conversion factors for air submersion and ground exposure pathways are further limited to drift diameters of 7.62 m and 5.5 m, corresponding to the main and emplacement drifts, respectively. If the final repository design significantly deviates from these drift dimensions, the results in this report may require revision. The dose conversion factors are further derived by using concrete of sufficient thickness to simulate the drift walls. The gamma-ray scattering properties of concrete are sufficiently similar to those of the host rock and proposed insert material; use of concrete will have no significant impact on the conclusions. The information in this report is presented primarily for use in performing pre-closure radiological safety evaluations of radiological contaminants, but it may also be used to develop strategies for contaminant leak detection and monitoring in the MGR. Included in this report are the methods for determining the source terms and release fractions, and mathematical models and model parameters for contaminant transport and distribution within the repository. Various particle behavior mechanisms that affect the transport of contaminant are included. These particle behavior mechanisms include diffusion, settling, resuspension, agglomeration and other deposition mechanisms.

F.R. Faillace; Y. Yuan

2000-08-31T23:59:59.000Z

73

Organic contaminant separator  

DOE Patents [OSTI]

A process is presented of sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium by (a) passing an initial aqueous medium including a minor amount of the organic contaminant through a composite tube comprised of a blend of a polyolefin and a polyester, the composite tube having an internal diameter of from about 0.1 to about 2.0 millimeters and being of sufficient length to permit the organic contaminant to adhere to the composite tube, (b) passing a solvent through the composite tube. The solvent is capable of separating the adhered organic contaminant from the composite tube. Further, an extraction apparatus is presented for sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium. The apparatus includes a composite tube comprised of a blend of a polyolefin and a polyester. The composite tube has an internal diameter of from about 0.1 to about 2.0 millimeters and has sufficient length to permit an organic contaminant contained within an aqueous medium passed therethrough to adhere to the composite tube. 2 figures.

Del Mar, P.

1993-12-28T23:59:59.000Z

74

Maximum entropy segmentation of broadcast news   

E-Print Network [OSTI]

speech recognizer and subsequently segmenting the text into utterances and topics. A maximum entropy approach is used to build statistical models for both utterance and topic segmentation. The experimental work addresses the effect on performance...

Christensen, Heidi; Kolluru, BalaKrishna; Gotoh, Yoshihiko; Renals, Steve

2005-01-01T23:59:59.000Z

75

Managing contaminated sites  

SciTech Connect (OSTI)

This book summarizes the generic principles of contaminated site management. The book walks the reader through contaminated site identification, risk assessment and the evaluation of remediation alternatives. The book is divided into two major sections, problem diagnosis and development of site restoration. In problem diagnosis, the general principles of site investigation are discussed, including the objectives and differences between tier 1,2, and 3 investigations. The principles of data collection and analysis are presented. A small quantitative discussion of statistical analysis is presented but in keeping with the objectives of the text is not sufficient comprehensive or detailed to provide much of a guide for the practitioner. Chapters on contaminant fate and transport processes and risk assessment help the reader understand the role of these issues in site investigation and remedial planning. A chapter is also included on elements of a site characterization activity, which summarizes some of the key considerations in conducting a site investigation.

Asante-Duah, D.K.

1997-12-31T23:59:59.000Z

76

Low contaminant formic acid fuel for direct liquid fuel cell  

DOE Patents [OSTI]

A low contaminant formic acid fuel is especially suited toward use in a direct organic liquid fuel cell. A fuel of the invention provides high power output that is maintained for a substantial time and the fuel is substantially non-flammable. Specific contaminants and contaminant levels have been identified as being deleterious to the performance of a formic acid fuel in a fuel cell, and embodiments of the invention provide low contaminant fuels that have improved performance compared to known commercial bulk grade and commercial purified grade formic acid fuels. Preferred embodiment fuels (and fuel cells containing such fuels) including low levels of a combination of key contaminants, including acetic acid, methyl formate, and methanol.

Masel, Richard I. (Champaign, IL); Zhu, Yimin (Urbana, IL); Kahn, Zakia (Palatine, IL); Man, Malcolm (Vancouver, CA)

2009-11-17T23:59:59.000Z

77

In situ remediation of uranium contaminated groundwater  

SciTech Connect (OSTI)

In an effort to develop cost-efficient techniques for remediating uranium contaminated groundwater at DOE Uranium Mill Tailing Remedial Action (UMTRA) sites nationwide, Sandia National Laboratories (SNL) deployed a pilot scale research project at an UMTRA site in Durango, CO. Implementation included design, construction, and subsequent monitoring of an in situ passive reactive barrier to remove Uranium from the tailings pile effluent. A reactive subsurface barrier is produced by emplacing a reactant material (in this experiment - various forms of metallic iron) in the flow path of the contaminated groundwater. Conceptually the iron media reduces and/or adsorbs uranium in situ to acceptable regulatory levels. In addition, other metals such as Se, Mo, and As have been removed by the reductive/adsorptive process. The primary objective of the experiment was to eliminate the need for surface treatment of tailing pile effluent. Experimental design, and laboratory and field preliminary results are discussed with regard to other potential contaminated groundwater treatment applications.

Dwyer, B.P.; Marozas, D.C. [Sandia National Labs., Albuquerque, NM (United States)

1997-12-31T23:59:59.000Z

78

In situ remediation of uranium contaminated groundwater  

SciTech Connect (OSTI)

In an effort to develop cost-efficient techniques for remediating uranium contaminated groundwater at DOE Uranium Mill Tailing Remedial Action (UMTRA) sites nationwide, Sandia National Laboratories (SNL) deployed a pilot scale research project at an UMTRA site in Durango, CO. Implementation included design, construction, and subsequent monitoring of an in situ passive reactive barrier to remove Uranium from the tailings pile effluent. A reactive subsurface barrier is produced by emplacing a reactant material (in this experiment various forms of metallic iron) in the flow path of the contaminated groundwater. Conceptually the iron media reduces and/or adsorbs uranium in situ to acceptable regulatory levels. In addition, other metals such as Se, Mo, and As have been removed by the reductive/adsorptive process. The primary objective of the experiment was to eliminate the need for surface treatment of tailing pile effluent. Experimental design, and laboratory and field results are discussed with regard to other potential contaminated groundwater treatment applications.

Dwyer, B.P.; Marozas, D.C.

1997-02-01T23:59:59.000Z

79

Cell development obeys maximum Fisher information  

E-Print Network [OSTI]

Eukaryotic cell development has been optimized by natural selection to obey maximal intracellular flux of messenger proteins. This, in turn, implies maximum Fisher information on angular position about a target nuclear pore complex (NPR). The cell is simply modeled as spherical, with cell membrane (CM) diameter 10 micron and concentric nuclear membrane (NM) diameter 6 micron. The NM contains about 3000 nuclear pore complexes (NPCs). Development requires messenger ligands to travel from the CM-NPC-DNA target binding sites. Ligands acquire negative charge by phosphorylation, passing through the cytoplasm over Newtonian trajectories toward positively charged NPCs (utilizing positive nuclear localization sequences). The CM-NPC channel obeys maximized mean protein flux F and Fisher information I at the NPC, with first-order delta I = 0 and approximate 2nd-order delta I = 0 stability to environmental perturbations. Many of its predictions are confirmed, including the dominance of protein pathways of from 1-4 proteins, a 4nm size for the EGFR protein and the approximate flux value F =10^16 proteins/m2-s. After entering the nucleus, each protein ultimately delivers its ligand information to a DNA target site with maximum probability, i.e. maximum Kullback-Liebler entropy HKL. In a smoothness limit HKL approaches IDNA/2, so that the total CM-NPC-DNA channel obeys maximum Fisher I. Thus maximum information approaches non-equilibrium, one condition for life.

B. R. Frieden; R. A. Gatenby

2014-04-29T23:59:59.000Z

80

Mercury contamination extraction  

DOE Patents [OSTI]

Mercury is removed from contaminated waste by firstly applying a sulfur reagent to the waste. Mercury in the waste is then permitted to migrate to the reagent and is stabilized in a mercury sulfide compound. The stable compound may then be removed from the waste which itself remains in situ following mercury removal therefrom.

Fuhrmann, Mark (Silver Spring, MD); Heiser, John (Bayport, NY); Kalb, Paul (Wading River, NY)

2009-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Screening Level Risk Assessment for the New Waste Calcining Facility  

SciTech Connect (OSTI)

This screening level risk assessment evaluates potential adverse human health and ecological impacts resulting from continued operations of the calciner at the New Waste Calcining Facility (NWCF) at the Idaho Nuclear Technology and Engineering Center (INTEC), Idaho National Engineering and Environmental Laboratory (INEEL). The assessment was conducted in accordance with the Environmental Protection Agency (EPA) report, Guidance for Performing Screening Level Risk Analyses at Combustion Facilities Burning Hazardous Waste. This screening guidance is intended to give a conservative estimate of the potential risks to determine whether a more refined assessment is warranted. The NWCF uses a fluidized-bed combustor to solidify (calcine) liquid radioactive mixed waste from the INTEC Tank Farm facility. Calciner off volatilized metal species, trace organic compounds, and low-levels of radionuclides. Conservative stack emission rates were calculated based on maximum waste solution feed samples, conservative assumptions for off gas partitioning of metals and organics, stack gas sampling for mercury, and conservative measurements of contaminant removal (decontamination factors) in the off gas treatment system. Stack emissions were modeled using the ISC3 air dispersion model to predict maximum particulate and vapor air concentrations and ground deposition rates. Results demonstrate that NWCF emissions calculated from best-available process knowledge would result in maximum onsite and offsite health and ecological impacts that are less then EPA-established criteria for operation of a combustion facility.

M. L. Abbott; K. N. Keck; R. E. Schindler; R. L. VanHorn; N. L. Hampton; M. B. Heiser

1999-05-01T23:59:59.000Z

82

LEACHING BEHAVIOR OF PETROLEUM CONTAMINATED SOILS STABILIZED WITH HIGH CARBON CONTENT FLY ASH  

E-Print Network [OSTI]

1 LEACHING BEHAVIOR OF PETROLEUM CONTAMINATED SOILS STABILIZED WITH HIGH CARBON CONTENT FLY ASH the stabilization of petroleum- contaminated soils (PCSs) using another recycled material, high carbon content fly; however, the level of petroleum contamination has a significant effect on the leaching properties

Aydilek, Ahmet

83

Management of Transuranic Contaminated Material  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To establish guidelines for the generation, treatment, packaging, storage, transportation, and disposal of transuranic (TRU) contaminated material.

1982-09-30T23:59:59.000Z

84

Active airborne contamination control using electrophoresis  

SciTech Connect (OSTI)

In spite of our best efforts, radioactive airborne contamination continues to be a formidable problem at many of the Department of Energy (DOE) weapons complex sites. For workers that must enter areas with high levels of airborne contamination, personnel protective equipment (PPE) can become highly restrictive, greatly diminishing productivity. Rather than require even more restrictive PPE for personnel in some situations, the Rocky Flats Plant (RFP) is actively researching and developing methods to aggressively combat airborne contamination hazards using electrophoretic technology. With appropriate equipment, airborne particulates can be effectively removed and collected for disposal in one simple process. The equipment needed to implement electrophoresis is relatively inexpensive, highly reliable, and very compact. Once airborne contamination levels are reduced, less PPE is required and a significant cost savings may be realized through decreased waste and maximized productivity. Preliminary ``cold,`` or non-radioactive, testing results at the RFP have shown the technology to be effective on a reasonable scale, with several potential benefits and an abundance of applications.

Veatch, B.D.

1994-06-01T23:59:59.000Z

85

Weak Scale From the Maximum Entropy Principle  

E-Print Network [OSTI]

The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\\cal{O}}(300\\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \\begin{equation} v_{h}\\sim\\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\

Yuta Hamada; Hikaru Kawai; Kiyoharu Kawana

2014-09-23T23:59:59.000Z

86

Weak Scale From the Maximum Entropy Principle  

E-Print Network [OSTI]

The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\\cal{O}}(300\\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \\begin{equation} v_{h}\\sim\\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\

Hamada, Yuta; Kawana, Kiyoharu

2014-01-01T23:59:59.000Z

87

Integrating Correlated Bayesian Networks Using Maximum Entropy  

SciTech Connect (OSTI)

We consider the problem of generating a joint distribution for a pair of Bayesian networks that preserves the multivariate marginal distribution of each network and satisfies prescribed correlation between pairs of nodes taken from both networks. We derive the maximum entropy distribution for any pair of multivariate random vectors and prescribed correlations and demonstrate numerical results for an example integration of Bayesian networks.

Jarman, Kenneth D.; Whitney, Paul D.

2011-08-30T23:59:59.000Z

88

Radioactive Contamination of Danish Territory  

E-Print Network [OSTI]

Risø-R-462 Radioactive Contamination of Danish Territory after Core-melt Accidents at the Barsebäck;#12;RIS0-R-462 RADIOACTIVE CONTAMINATION OF DANISH TERRITORY AFTER CORE-MELT ACCIDENTS AT THE BARSEBACK. An assessment is made of the radioactive contamination of Danish territory in the event of a core-melt accident

89

Containment of subsurface contaminants  

DOE Patents [OSTI]

A barrier is disclosed for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates. 5 figs.

Corey, J.C.

1994-09-06T23:59:59.000Z

90

Containment of subsurface contaminants  

DOE Patents [OSTI]

A barrier for reducing the spread of a plume of subsurface contaminants. The apparatus includes a well system for injecting a fluid, such as air, just outside and below the periphery of the plume. The fluid is injected at a pressure sufficient to lower the hydraulic conductivity of the soil from the point of injection to the surface thus establishing a curtain-like barrier to groundwater movement. The barrier is established upgradient of the plume to divert groundwater away, or preferably completely around the plume to reduce the flow of groundwater into or out of the plume. The barrier enables the remediation of the confined contamination and then, when the injection of the fluid is halted, the barrier quickly dissipates.

Corey, John C. (Aiken, SC)

1994-01-01T23:59:59.000Z

91

GROUND WATER CONTAMINATION  

SciTech Connect (OSTI)

As required by the terms of the above referenced grant, the following summary serves as the Final Report for that grant. The grant relates to work performed at two separate sites, the Hoe Creek Underground Coal Gasification Site south of Gillette, Wyoming, and the Rock Springs In-Situ Oil Shale Retort Site near Rock Springs, Wyoming. The primary concern to the State of Wyoming at each site is ground water contamination (the primary contaminants of concern are benzene and related compounds), and the purpose of the grant has been to provide tiding for a Geohydrologist at the appropriate State agency, specifically the Land Quality Division (LQD) of the Wyoming Department of Environmental Quality. The LQD Geohydrologist has been responsible for providing technical and regulatory support to DOE for ground water remediation and subsequent surface reclamation. Substantial progress has been made toward remediation of the sites, and continuation of LQD involvement in the remediation and reclamation efforts is addressed.

Unknown

1999-09-01T23:59:59.000Z

92

Purifying contaminated water  

SciTech Connect (OSTI)

Process for removing biorefractory compounds from contaminated water (e.g., oil shale retort waste-water) by contacting same with fragmented raw oil shale. Biorefractory removal is enhanced by preactivating the oil shale with at least one member of the group of carboxylic, acids, alcohols, aldehydes, ketones, ethers, amines, amides, sulfoxides, mixed ether-esters and nitriles. Further purification is obtained by stripping, followed by biodegradation and removal of the cells.

Daughton, Christian G. (San Pablo, CA)

1983-01-01T23:59:59.000Z

93

Understanding Contamination; Twenty Years of Simulating Radiological Contamination  

SciTech Connect (OSTI)

A wide variety of simulated contamination methods have been developed by researchers to reproducibly test radiological decontamination methods. Some twenty years ago a method of non-radioactive contamination simulation was proposed at the Idaho National Laboratory (INL) that mimicked the character of radioactive cesium and zirconium contamination on stainless steel. It involved baking the contamination into the surface of the stainless steel in order to 'fix' it into a tenacious, tightly bound oxide layer. This type of contamination was particularly applicable to nuclear processing facilities (and nuclear reactors) where oxide growth and exchange of radioactive materials within the oxide layer became the predominant model for material/contaminant interaction. Additional simulation methods and their empirically derived basis (from a nuclear fuel reprocessing facility) are discussed. In the last ten years the INL, working with the Defense Advanced Research Projects Agency (DARPA) and the National Homeland Security Research Center (NHSRC), has continued to develop contamination simulation methodologies. The most notable of these newer methodologies was developed to compare the efficacy of different decontamination technologies against radiological dispersal device (RDD, 'dirty bomb') type of contamination. There are many different scenarios for how RDD contamination may be spread, but the most commonly used one at the INL involves the dispersal of an aqueous solution containing radioactive Cs-137. This method was chosen during the DARPA projects and has continued through the NHSRC series of decontamination trials and also gives a tenacious 'fixed' contamination. Much has been learned about the interaction of cesium contamination with building materials, particularly concrete, throughout these tests. The effects of porosity, cation-exchange capacity of the material and the amount of dirt and debris on the surface are very important factors. The interaction of the contaminant/substrate with the particular decontamination technology is also very important. Results of decontamination testing from hundreds of contaminated coupons have lead to certain conclusions about the contamination and the type of decontamination methods being deployed. A recent addition to the DARPA initiated methodology simulates the deposition of nuclear fallout. This contamination differs from previous tests in that it has been developed and validated purely to simulate a 'loose' type of contamination. This may represent the first time that a radiologically contaminated 'fallout' stimulant has been developed to reproducibly test decontamination methods. While no contaminant/methodology may serve as a complete example of all aspects that could be seen in the field, the study of this family of simulation methods provides insight into the nature of radiological contamination.

Emily Snyder; John Drake; Ryan James

2012-02-01T23:59:59.000Z

94

Surface Contamination Surface contamination from radioactive isotopes is a source of background in the Borex-  

E-Print Network [OSTI]

Chapter 5 Surface Contamination Surface contamination from radioactive isotopes is a source contamination is primarily a problem because the radioactive contaminants can be trans- ferred from the surfaces detector components that come in contact with the scintillator. Preventing radioactive contamination

95

Understanding Mechanisms of Radiological Contamination  

SciTech Connect (OSTI)

Over the last 50 years, the study of radiological contamination and decontamination has expanded significantly. This paper addresses the mechanisms of radiological contamination that have been reported and then discusses which methods have recently been used during performance testing of several different decontamination technologies. About twenty years ago the Idaho Nuclear Technology Engineering Center (INTEC) at the INL began a search for decontamination processes which could minimize secondary waste. In order to test the effectiveness of these decontamination technologies, a new simulated contamination, termed SIMCON, was developed. SIMCON was designed to replicate the types of contamination found on stainless steel, spent fuel processing equipment. Ten years later, the INL began research into methods for simulating urban contamination resulting from a radiological dispersal device (RDD). This work was sponsored by the Defense Advanced Research Projects Agency (DARPA) and included the initial development an aqueous application of contaminant to substrate. Since 2007, research sponsored by the US Environmental Protection Agency (EPA) has advanced that effort and led to the development of a contamination method that simulates particulate fallout from an Improvised Nuclear Device (IND). The IND method diverges from previous efforts to create tenacious contamination by simulating a reproducible “loose” contamination. Examining these different types of contamination (and subsequent decontamination processes), which have included several different radionuclides and substrates, sheds light on contamination processes that occur throughout the nuclear industry and in the urban environment.

Rick Demmer; John Drake; Ryan James, PhD

2014-03-01T23:59:59.000Z

96

In vitro gastrointestinal mimetic protocol for measuring bioavailable contaminants  

DOE Patents [OSTI]

The present invention relates to measurements of contaminants in the soil and other organic or environmental materials, using a biologically relevant chemical analysis that will measure the amount of contaminants in a given sample that may be expected to be absorbed by a human being ingesting the contaminated soil. According to the present invention, environmental samples to be tested are added to a pre-prepared physiological composition of bile salts and lipids. They are thoroughly mixed and then the resulting mixture is separated e.g. by centrifugation. The supernatant is then analyzed for the presence of contaminants and these concentrations are compared to the level of contaminants in the untreated samples. It is important that the bile salts and lipids be thoroughly pre-mixed to form micelles.

Holman, Hoi-Ying N. (Berkeley, CA)

2000-01-01T23:59:59.000Z

97

Excited nucleon spectrum from lattice QCD with maximum entropy method  

E-Print Network [OSTI]

We study excited states of the nucleon in quenched lattice QCD with the spectral analysis using the maximum entropy method. Our simulations are performed on three lattice sizes $16^3\\times 32$, $24^3\\times 32$ and $32^3\\times 32$, at $\\beta=6.0$ to address the finite volume issue. We find a significant finite volume effect on the mass of the Roper resonance for light quark masses. After removing this systematic error, its mass becomes considerably reduced toward the direction to solve the level order puzzle between the Roper resonance $N'(1440)$ and the negative-parity nucleon $N^*(1535)$.

K. Sasaki; S. Sasaki; T. Hatsuda; M. Asakawa

2003-09-29T23:59:59.000Z

98

Tissue Radiation Response with Maximum Tsallis Entropy  

SciTech Connect (OSTI)

The expression of survival factors for radiation damaged cells is currently based on probabilistic assumptions and experimentally fitted for each tumor, radiation, and conditions. Here, we show how the simplest of these radiobiological models can be derived from the maximum entropy principle of the classical Boltzmann-Gibbs expression. We extend this derivation using the Tsallis entropy and a cutoff hypothesis, motivated by clinical observations. The obtained expression shows a remarkable agreement with the experimental data found in the literature.

Sotolongo-Grau, O.; Rodriguez-Perez, D.; Antoranz, J. C.; Sotolongo-Costa, Oscar [UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain); UNED, Departamento de Fisica Matematica y de Fluidos, 28040 Madrid (Spain) and University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba); University of Havana, Catedra de Sistemas Complejos Henri Poincare, Havana 10400 (Cuba)

2010-10-08T23:59:59.000Z

99

A global maximum power point tracking DC-DC converter  

E-Print Network [OSTI]

This thesis describes the design, and validation of a maximum power point tracking DC-DC converter capable of following the true global maximum power point in the presence of other local maximum. It does this without the ...

Duncan, Joseph, 1981-

2005-01-01T23:59:59.000Z

100

Accelerated maximum likelihood parameter estimation for stochastic biochemical systems  

E-Print Network [OSTI]

as: Daigle et al. : Accelerated maximum likelihood parame-Gillespie DT: Approximate accelerated stochastic simulationARTICLE Open Access Accelerated maximum likelihood parameter

Daigle, Bernie J; Roh, Min K; Petzold, Linda R; Niemi, Jarad

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

articulatorily constrained maximum: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

weight spanning forests. Amitabha Bagchi; Ankur Bhargava; Torsten Suel 2005-01-01 27 Maximum Entropy Correlated Equilibria MIT - DSpace Summary: We study maximum entropy...

102

Innovative technology for contamination control in plasma processing  

SciTech Connect (OSTI)

The causes and contributing factors to wafer contamination during plasma processing are discussed in the context of future technologies for controlling particle contamination by tool and process design and by the development of wafer dry cleaning technology. The importance of these developments is linked with the history of technological innovation and with the continuing evolution of the cleanroom from a highly developed facility for reducing ambient particle levels to an integrated, synergistic approach involving facilities and tooling for impeding the formation and transport of particles while also actively removing particles from sensitive surfaces. The methods, strategy and requirements for innovation in contamination control for plasma processing is discussed from a diachronic viewpoint.

Selwyn, G.S.

1994-10-01T23:59:59.000Z

103

Contaminated nickel scrap processing  

SciTech Connect (OSTI)

The DOE will soon choose between treating contaminated nickel scrap as a legacy waste and developing high-volume nickel decontamination processes. In addition to reducing the volume of legacy wastes, a decontamination process could make 200,000 tons of this strategic metal available for domestic use. Contaminants in DOE nickel scrap include {sup 234}Th, {sup 234}Pa, {sup 137}Cs, {sup 239}Pu (trace), {sup 60}Co, U, {sup 99}Tc, and {sup 237}Np (trace). This report reviews several industrial-scale processes -- electrorefining, electrowinning, vapormetallurgy, and leaching -- used for the purification of nickel. Conventional nickel electrolysis processes are particularly attractive because they use side-stream purification of process solutions to improve the purity of nickel metal. Additionally, nickel purification by electrolysis is effective in a variety of electrolyte systems, including sulfate, chloride, and nitrate. Conventional electrorefining processes typically use a mixed electrolyte which includes sulfate, chloride, and borate. The use of an electrorefining or electrowinning system for scrap nickel recovery could be combined effectively with a variety of processes, including cementation, solvent extraction, ion exchange, complex-formation, and surface sorption, developed for uranium and transuranic purification. Selected processes were reviewed and evaluated for use in nickel side-stream purification. 80 refs.

Compere, A.L.; Griffith, W.L.; Hayden, H.W.; Johnson, J.S. Jr.; Wilson, D.F.

1994-12-01T23:59:59.000Z

104

Emission Standards for Contaminants (Iowa)  

Broader source: Energy.gov [DOE]

These regulations list emissions standards for various contaminants, and contain special requirements for anaerobic lagoons. These regulations also describe alternative emissions limits, which may...

105

Evaluation of Groundwater Impacts to Support the National Environmental Policy Act Environmental Assessment for the INL Remote-Handled Low-Level Waste Disposal Project  

SciTech Connect (OSTI)

Groundwater impacts have been analyzed for the proposed remote-handled low-level waste disposal facility. The analysis was prepared to support the National Environmental Policy Act environmental assessment for the top two ranked sites for the proposed disposal facility. A four-phase screening and analysis approach was documented and applied. Phase I screening was site independent and applied a radionuclide half-life cut-off of 1 year. Phase II screening applied the National Council on Radiation Protection analysis approach and was site independent. Phase III screening used a simplified transport model and site-specific geologic and hydrologic parameters. Phase III neglected the infiltration-reducing engineered cover, the sorption influence of the vault system, dispersion in the vadose zone, vertical dispersion in the aquifer, and the release of radionuclides from specific waste forms. These conservatisms were relaxed in the Phase IV analysis which used a different model with more realistic parameters and assumptions. Phase I screening eliminated 143 of the 246 radionuclides in the inventory from further consideration because each had a half-life less than 1 year. An additional 13 were removed because there was no ingestion dose coefficient available. Of the 90 radionuclides carried forward from Phase I, 57 radionuclides had simulated Phase II screening doses exceeding 0.4 mrem/year. Phase III and IV screening compared the maximum predicted radionuclide concentration in the aquifer to maximum contaminant levels. Of the 57 radionuclides carried forward from Phase II, six radionuclides were identified in Phase III as having simulated future aquifer concentrations exceeding maximum contaminant limits. An additional seven radionuclides had simulated Phase III groundwater concentrations exceeding 1/100th of their respective maximum contaminant levels and were also retained for Phase IV analysis. The Phase IV analysis predicted that none of the thirteen remaining radionuclides would exceed the maximum contaminant levels for either site location. The predicted cumulative effective dose equivalent from all 13 radionuclides also was less than the dose criteria set forth in Department of Energy Order 435.1 for each site location. An evaluation of composite impacts showed one site is preferable over the other based on the potential for commingling of groundwater contamination with other facilities.

Annette Schafer, Arthur S. Rood, A. Jeffrey Sondrup

2011-12-23T23:59:59.000Z

106

Radiological Survey of Contaminated Installations of Research Reactor before Dismantling in High Dose Conditions with Complex for Remote Measurements of Radioactivity - 12069  

SciTech Connect (OSTI)

Decontamination and decommissioning of the research reactors MR (Testing Reactor) and RFT (Reactor of Physics and Technology) has recently been initiated in the National Research Center (NRC) 'Kurchatov institute', Moscow. These research reactors have a long history and many installations - nine loop facilities for experiments with different kinds of fuel. When decommissioning nuclear facilities it is necessary to measure the distribution of radioactive contamination in the rooms and at the equipment at high levels of background radiation. At 'Kurchatov Institute' some special remote control measuring systems were developed and they are applied during dismantling of the reactors MR and RFT. For a survey of high-level objects a radiometric system mounted on the robotic Brokk vehicle is used. This system has two (4? and collimated) dose meters and a high resolution video camera. Maximum measured dose rate for this system is ?8.5 Sv/h. To determine the composition of contaminants, a portable spectrometric system is used. It is a remotely controlled, collimated detector for scanning the distribution of radioactive contamination. To obtain a detailed distribution of contamination a remote-controlled gamma camera is applied. For work at highly contaminated premises with non-uniform background radiation, another camera is equipped with rotating coded mask (coded aperture imaging). As a result, a new system of instruments for remote radioactivity measurements with wide range of sensitivity and angular resolution was developed. The experience and results of measurements in different areas of the reactor and at its loop installations, with emphasis on the radioactive survey of highly-contaminated samples, are presented. These activities are conducted under the Federal Program for Nuclear and Radiation Safety of Russia. Adaptation of complex remote measurements of radioactivity and survey of contaminated installations of research reactor before dismantling in high dose conditions has proven successful. The radioactivity measuring devices for operation at high, non-uniform dose background were tested in the field and a new data of measurement of contamination distribution in the premises and installations were obtained. (authors)

Danilovich, Alexey; Ivanov, Oleg; Lemus, Alexey; Smirnov, Sergey; Stepanov, Vyacheslav; Volkovich, Anatoly [National Research Centre 'Kurchatov Institute', Moscow (Russian Federation)

2012-07-01T23:59:59.000Z

107

Maximum mass of magnetic white dwarfs  

E-Print Network [OSTI]

We revisit in this work the problem of the maximum masses of magnetized White Dwarfs (WD). The impact of a strong magnetic field onto the structure equations is addressed. The pressures become anisotropic due to the presence of the magnetic field and split into a parallel and perpendicular components. We first construct stable solutions of TOV equations for the parallel pressures, and found that physical solutions vanish for the perpendicular pressure when $B \\gtrsim 10^{13}$ G. This fact establishes an upper bound for a magnetic field and the stability of the configurations in the (quasi) spherical approximation. Our findings also indicate that it is not possible to obtain stable magnetized WD with super Chandrasekhar masses because the values of the magnetic field needed for them are higher than this bound. To proceed into the anisotropic regime, we derived structure equations appropriated for a cylindrical metric with anisotropic pressures. From the solutions of the structure equations in cylindrical symme...

Paret, D Manreza; Horvath, J E

2015-01-01T23:59:59.000Z

108

Maximum screening fields of superconducting multilayer structures  

E-Print Network [OSTI]

It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields $H_s$ of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness $\\sim 0.1\\; \\mu$m at the Nb surface could increase $H_s\\simeq 240$ mT of a clean Nb up to $H_s\\simeq 290$ mT. Optimized multilayers of Nb$_3$Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.

Gurevich, Alex

2015-01-01T23:59:59.000Z

109

Radioactive Contamination of Danish Territory  

E-Print Network [OSTI]

» & Risø-R-462 Radioactive Contamination of Danish Territory after Core-melt Accidents 1982 Risø National Laboratory, DK-4000 Roskilde, Denmark #12;RIS�-R-462 RADIOACTIVE CONTAMINATION. Heikel Vinther, L. Warming and A. Aarkrog Abstract. An assessment is made of the radioactive

110

A ThreeDimensional Finite Element Simulation for Transport of Nuclear Waste Contamination in Porous Media \\Lambda  

E-Print Network [OSTI]

A Three­Dimensional Finite Element Simulation for Transport of Nuclear Waste Contamination for transport of nuclear­waste contamination in three­dimensional porous media are presented with a description of contamination of groundwater by high­level nuclear waste and a wide variety of other sources makes a proper

Ewing, Richard E.

111

USE OF APATITE FOR CHEMICAL STABILIZATION OF SUBSURFACE CONTAMINANTS  

SciTech Connect (OSTI)

Groundwater at many Federal and civilian industrial sites is often contaminated with toxic metals at levels that present a potential concern to regulatory agencies. The U.S. Department of Energy (DOE) has some unique problems associated with radionuclides (primarily uranium), but metal contaminants most likely drive risk-based cleanup decisions, from the perspective of human health, in groundwater at DOE and U.S. Environmental Protection Agency (EPA) Superfund Sites include lead (Pb), arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), zinc (Zn), selenium (Se), antimony (Sb), copper (Cu) and nickel (Ni). Thus, the regulatory ''drivers'' for toxic metals in contaminated soils/groundwaters are very comparable for Federal and civilian industrial sites, and most sites have more than one metal above regulatory action limits. Thus improving the performance of remedial technologies for metal-contaminated groundwater will have ''dual use'' (Federal and civilian) benefit.

Dr. William D. Bostick

2003-05-01T23:59:59.000Z

112

Controlling Beryllium Contaminated Material And Equipment For The Building 9201-5 Legacy Material Disposition Project  

SciTech Connect (OSTI)

This position paper addresses the management of beryllium contamination on legacy waste. The goal of the beryllium management program is to protect human health and the environment by preventing the release of beryllium through controlling surface contamination. Studies have shown by controlling beryllium surface contamination, potential airborne contamination is reduced or eliminated. Although there are areas in Building 9201-5 that are contaminated with radioactive materials and mercury, only beryllium contamination is addressed in this management plan. The overall goal of this initiative is the compliant packaging and disposal of beryllium waste from the 9201-5 Legacy Material Removal (LMR) Project to ensure that beryllium surface contamination and any potential airborne release of beryllium is controlled to levels as low as practicable in accordance with 10 CFR 850.25.

Reynolds, T. D.; Easterling, S. D.

2010-10-01T23:59:59.000Z

113

Maximum Entropy Method Approach to $?$ Term  

E-Print Network [OSTI]

In Monte Carlo simulations of lattice field theory with a $\\theta$ term, one confronts the complex weight problem, or the sign problem. This is circumvented by performing the Fourier transform of the topological charge distribution $P(Q)$. This procedure, however, causes flattening phenomenon of the free energy $f(\\theta)$, which makes study of the phase structure unfeasible. In order to treat this problem, we apply the maximum entropy method (MEM) to a Gaussian form of $P(Q)$, which serves as a good example to test whether the MEM can be applied effectively to the $\\theta$ term. We study the case with flattening as well as that without flattening. In the latter case, the results of the MEM agree with those obtained from the direct application of the Fourier transform. For the former, the MEM gives a smoother $f(\\theta)$ than that of the Fourier transform. Among various default models investigated, the images which yield the least error do not show flattening, although some others cannot be excluded given the uncertainty related to statistical error.

Masahiro Imachi; Yasuhiko Shinno; Hiroshi Yoneyama

2004-06-09T23:59:59.000Z

114

Potential Risks of Freshwater Aquifer Contamination with Geosequestration  

SciTech Connect (OSTI)

Substantial leakage of CO{sub 2} from deep geological strata to shallow potable aquifers is likely to be rare, but chemical detection of potential leakage nonetheless remains an integral component of any safe carbon capture and storage system. CO{sub 2} that infiltrates an unconfined freshwater aquifer will have an immediate impact on water chemistry by lowering pH in most cases and by altering the concentration of total dissolved solids. Chemical signatures in affected waters provide an important opportunity for early detection of leaks. In the presence of CO{sub 2}, trace elements such as Mn, Fe, and Ca can increase by an order of magnitude or more above control concentrations within 100 days. Therefore, these and other elements should be monitored along with pH as geochemical markers of potential CO{sub 2} leaks. Dissolved inorganic carbon and alkalinity can also be rapidly responsive to CO{sub 2} and are stable indicators of a leak. Importantly, such changes may be detectable long before direct changes in CO{sub 2} are observed. The experimental results also suggest that the relative severity of the impact of leaks on overlying drinking-water aquifers should be considered in the selection of CO{sub 2} sequestration sites. One primary selection criteria should be metal and metalloid availability, such as uranium and arsenic abundance, to carefully monitor chemical species that could trigger changes above maximum contaminant levels (MCLs). Overall, the risks of leakage from underground CO{sub 2} storage are real but appear to be manageable if systems are closely monitored.

Jackson, Robert

2013-09-30T23:59:59.000Z

115

GMM Estimation of a Maximum Entropy Distribution with Interval Data  

E-Print Network [OSTI]

GMM Estimation of a Maximum Entropy Distribution with Interval Data Ximing Wu* and Jeffrey M estimate it using a simple yet flexible maximum entropy density. Our Monte Carlo simulations show that the proposed maximum entropy density is able to approximate various distributions extremely well. The two

Perloff, Jeffrey M.

116

LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL  

SciTech Connect (OSTI)

The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with conventional landfills. This is the highest methane recovery rate per unit waste, and thus progress toward stabilization, documented anywhere for such a large waste mass. This high recovery rate is attributed to moisture, and elevated temperature attained inexpensively during startup. Economic analyses performed under Phase I of this NETL contract indicate ''greenhouse cost effectiveness'' to be excellent. Other benefits include substantial waste volume loss (over 30%) which translates to extended landfill life. Other environmental benefits include rapidly improved quality and stabilization (lowered pollutant levels) in liquid leachate which drains from the waste.

Don Augenstein

2001-02-01T23:59:59.000Z

117

Method for testing earth samples for contamination by organic contaminants  

DOE Patents [OSTI]

Provided is a method for testing earth samples for contamination by organic contaminants, and particularly for aromatic compounds such as those found in diesel fuel and other heavy fuel oils, kerosene, creosote, coal oil, tars and asphalts. A drying step is provided in which a drying agent is contacted with either the earth sample or a liquid extract phase to reduce to possibility of false indications of contamination that could occur when humic material is present in the earth sample. This is particularly a problem when using relatively safe, non-toxic and inexpensive polar solvents such as isopropyl alcohol since the humic material tends to be very soluble in those solvents when water is present. Also provided is an ultraviolet spectroscopic measuring technique for obtaining an indication as to whether a liquid extract phase contains aromatic organic contaminants. In one embodiment, the liquid extract phase is subjected to a narrow and discrete band of radiation including a desired wave length and the ability of the liquid extract phase to absorb that wavelength of ultraviolet radiation is measured to provide an indication of the presence of aromatic organic contaminants.

Schabron, John F. (Laramie, WY)

1996-01-01T23:59:59.000Z

118

Method for testing earth samples for contamination by organic contaminants  

DOE Patents [OSTI]

Provided is a method for testing earth samples for contamination by organic contaminants, and particularly for aromatic compounds such as those found in diesel fuel and other heavy fuel oils, kerosene, creosote, coal oil, tars and asphalts. A drying step is provided in which a drying agent is contacted with either the earth sample or a liquid extract phase to reduce to possibility of false indications of contamination that could occur when humic material is present in the earth sample. This is particularly a problem when using relatively safe, non-toxic and inexpensive polar solvents such as isopropyl alcohol since the humic material tends to be very soluble in those solvents when water is present. Also provided is an ultraviolet spectroscopic measuring technique for obtaining an indication as to whether a liquid extract phase contains aromatic organic contaminants. In one embodiment, the liquid extract phase is subjected to a narrow and discrete band of radiation including a desired wave length and the ability of the liquid extract phase to absorb that wavelength of ultraviolet radiation is measured to provide an indication of the presence of aromatic organic contaminants. 2 figs.

Schabron, J.F.

1996-10-01T23:59:59.000Z

119

Hydraulic Containment of TCE Contaminated Groundwater at the DOE Portsmouth Gaseous Diffusion Plant  

SciTech Connect (OSTI)

This paper will describe the progress of a groundwater remedial action at the Portsmouth Gaseous Diffusion Plant (PORTS), a Department of Energy (DOE) facility that enriched uranium from the early 1950's until 2000. The X-749 southern boundary hydraulic containment system, combining a four-well extraction system with a previously constructed subsurface barrier wall, has been employed at PORTS. The hydraulic containment project has been implemented as part of containment and remediation of the X-749/X-120 area trichloroethylene (TCE) contaminant. The X-749/X-120 groundwater contaminant plume is located in the south central section (Quadrant I) of the PORTS facility. The plume is associated with the former X-120 Goodyear Training Facility and a landfill known as the X-749 Contaminated Materials Disposal Facility. The principal contaminants of concern are chlorinated solvents (primarily TCE) and technetium-99 (Tc-99). A subsurface barrier wall (X-749 South Barrier Wall) was completed in 1994 at the PORTS southern reservation boundary as an interim remedial measure to slow the advancement of the leading edge of the contaminated groundwater plume or to prevent the plume from migrating off DOE property. Remedial measures identified by Ohio Environmental Protection Agency (Ohio EPA) included installation of a barrier wall around the eastern and southern portions of the X-749 landfill to provide source control and installation of a phyto-remediation system to help contain groundwater flow and remove volatile organic compounds. Previous remedial measures that were implemented as elements of 'closures' on the X-749 landfill included a multimedia cap, barrier walls, and a groundwater collection system. Despite these measures, the X-749/X-120 groundwater plume has migrated beyond the southern DOE property boundary. Current TCE concentrations in off-site groundwater monitoring wells are below the preliminary remediation goal and drinking water maximum contaminant level for TCE of 5 {mu}g/kg, but continue to increase. Hydraulic containment was selected as the method for controlling the plume at the southern DOE property boundary. Recent borings and pumping tests indicate that approximately a 400-foot section of the existing subsurface barrier wall near the DOE property boundary may been improperly keyed into the Sunbury Shale bedrock which underlies the unconsolidated uppermost Gallia sand and gravel aquifer (Gallia). This gap is reported to be as much as 4 vertical feet. In addition, the X-749 groundwater plume is migrating around the western end of the X-749 South Barrier Wall. Four groundwater extraction wells were installed at the DOE property boundary to provide hydraulic control of the plume currently flowing under and around the existing subsurface barrier wall. Placement of the new extraction wells was based on groundwater modeling and data collected from pumping tests in the area. The extracted groundwater is being sent to the on-site X-622 Groundwater Treatment Facility via subsurface piping. The hydraulic containment system began operation in June 2007. The preliminary water elevations from monitoring wells in the vicinity of two of the four extraction wells demonstrate a significant decrease in groundwater potentiometric head in the southern boundary area. The current extraction rates should be adequate to contain the leading edge of the contaminant plume. Monitoring wells in the area will continue to be sampled on a quarterly basis. (authors)

Lewis, A.C.; Rieske, D.P.G.; Baird, D.R.P.E. [CDM, Piketon, OH (United States)

2008-07-01T23:59:59.000Z

120

THE CONTRIBUTION OF RADIO GALAXY CONTAMINATION TO MEASUREMENTS OF THE SUNYAEV-ZEL'DOVICH DECREMENT IN MASSIVE GALAXY CLUSTERS AT 140 GHz WITH BOLOCAM  

SciTech Connect (OSTI)

We describe in detail our characterization of the compact radio source population in 140 GHz Bolocam observations of a set of 45 massive galaxy clusters. We use a combination of 1.4 and 30 GHz data to select a total of 28 probable cluster-member radio galaxies and also to predict their 140 GHz flux densities. All of these galaxies are steep-spectrum radio sources and they are found preferentially in the cool-core clusters within our sample. In particular, 11 of the 12 brightest cluster-member radio sources are associated with cool-core systems. Although none of the individual galaxies are robustly detected in the Bolocam data, the ensemble-average flux density at 140 GHz is consistent with, but slightly lower than, the extrapolation from lower frequencies assuming a constant spectral index. In addition, our data indicate an intrinsic scatter of {approx_equal} 30% around the power-law extrapolated flux densities at 140 GHz, although our data do not tightly constrain this scatter. For our cluster sample, which is composed of high-mass and moderate-redshift systems, we find that the maximum fractional change in the Sunyaev-Zel'dovich signal integrated over any single cluster due to the presence of these radio sources is {approx_equal} 20%, and only {approx_equal} 1/4 of the clusters show a fractional change of more than 1%. The amount of contamination is strongly dependent on cluster morphology, and nearly all of the clusters with {>=}1% contamination are cool-core systems. This result indicates that radio contamination is not significant compared with current noise levels in 140 GHz images of massive clusters and is in good agreement with the level of radio contamination found in previous results based on lower frequency data or simulations.

Sayers, J.; Mroczkowski, T.; Czakon, N. G.; Golwala, S. R.; Downes, T. P.; Muchovej, S. J. C.; Siegel, S. [Division of Physics, Math, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States)] [Division of Physics, Math, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Mantz, A. [Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)] [Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Ameglio, S.; Pierpaoli, E.; Shitanishi, J. A. [Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089 (United States)] [Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089 (United States); Koch, P. M.; Lin, K.-Y.; Umetsu, K. [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)] [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Molnar, S. M. [LeCosPA Center, National Taiwan University, Taipei 10617, Taiwan (China)] [LeCosPA Center, National Taiwan University, Taipei 10617, Taiwan (China); Moustakas, L., E-mail: jack@caltech.edu [Jet Propulsion Laboratory, Pasadena, CA 91109 (United States)

2013-02-20T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Mercury contaminated sediment sites—An evaluation of remedial options  

SciTech Connect (OSTI)

Mercury (Hg) is a naturally-occurring element that is ubiquitous in the aquatic environment. Though efforts have been made in recent years to decrease Hg emissions, historically-emitted Hg can be retained in the sediments of aquatic bodies where they may be slowly converted to methylmercury (MeHg). Consequently, Hg in historically-contaminated sediments can result in high levels of significant exposure for aquatic species, wildlife and human populations consuming fish. Even if source control of contaminated wastewater is achievable, it may take a very long time, perhaps decades, for Hg-contaminated aquatic systems to reach relatively safe Hg levels in both water and surface sediment naturally. It may take even longer if Hg is present at higher concentration levels in deep sediment. Hg contaminated sediment results from previous releases or ongoing contributions from sources that are difficult to identify. Due to human activities or physical, chemical, or biological processes (e.g. hydrodynamic flows, bioturbation, molecular diffusion, and chemical transformation), the buried Hg can be remobilized into the overlying water. Hg speciation in the water column and sediments critically affect the reactivity (i.e. conversion of inorganic Hg(II) to MeHg), transport, and its exposure to living organisms. Also, geochemical conditions affect the activity of methylating bacteria and its availability for methylation. This review paper discusses remedial considerations (e.g. key chemical factors in fate and transport of Hg, source characterization and control, environmental management procedures, remediation options, modeling tools) and includes practical case studies for cleaning up Hg-contaminated sediment sites. -- Highlights: ? Managing mercury-contaminated sediment sites are challenging to remediate. ? Remediation technologies are making a difference in managing these sites. ? Partitioning plays a dominant role in the distribution of mercury species. ? Mathematical models can be used to help us understand the chemistry and processes.

Randall, Paul M., E-mail: randall.paul@epa.gov [U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, OH 45268 (United States); Chattopadhyay, Sandip, E-mail: Sandip.Chattopadhyay@tetratech.com [Tetra Tech, Inc., 250 West Court Street, Suite 200W, Cincinnati, OH 45202 (United States)] [Tetra Tech, Inc., 250 West Court Street, Suite 200W, Cincinnati, OH 45202 (United States)

2013-08-15T23:59:59.000Z

122

Screening of contaminants in Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee  

SciTech Connect (OSTI)

Waste Area Grouping 2 (WAG 2) of the Oak Ridge National Laboratory (ORNL) is located in the White Oak Creek Watershed and is composed of White Oak Creek Embayment, White Oak Lake and associated floodplain, and portions of White Oak Creek (WOC) and Melton Branch downstream of ORNL facilities. Contaminants leaving other ORNL WAGs in the WOC watershed pass through WAG 2 before entering the Clinch River. Health and ecological risk screening analyses were conducted on contaminants in WAG 2 to determine which contaminants were of concern and would require immediate consideration for remedial action and which contaminants could be assigned a low priority or further study. For screening purposes, WAG 2 was divided into four geographic reaches: Reach 1, a portion of WOC; Reach 2, Melton Branch; Reach 3, White Oak Lake and the floodplain area to the weirs on WOC and Melton Branch; and Reach 4, the White Oak Creek Embayment, for which an independent screening analysis has been completed. Screening analyses were conducted using data bases compiled from existing data on carcinogenic and noncarcinogenic contaminants, which included organics, inorganics, and radionuclides. Contaminants for which at least one ample had a concentration above the level of detection were placed in a detectable contaminants data base. Those contaminants for which all samples were below the level of detection were placed in a nondetectable contaminants data base.

Blaylock, B.G.; Frank, M.L.; Hoffman, F.O.; Hook, L.A.; Suter, G.W.; Watts, J.A.

1992-07-01T23:59:59.000Z

123

Method for removal of beryllium contamination from an article  

DOE Patents [OSTI]

A method of removal of beryllium contamination from an article is disclosed. The method typically involves dissolving polyisobutylene in a solvent such as hexane to form a tackifier solution, soaking the substrate in the tackifier to produce a preform, and then drying the preform to produce the cleaning medium. The cleaning media are typically used dry, without any liquid cleaning agent to rub the surface of the article and remove the beryllium contamination below a non-detect level. In some embodiments no detectible residue is transferred from the cleaning wipe to the article as a result of the cleaning process.

Simandl, Ronald F.; Hollenbeck, Scott M.

2012-12-25T23:59:59.000Z

124

Cleaning Contaminated Water at Fukushima  

SciTech Connect (OSTI)

Crystalline Silico-Titanates (CSTs) are synthetic zeolites designed by Sandia National Laboratories scientists to selectively capture radioactive cesium and other group I metals. They are being used for cleanup of radiation-contaminated water at the Fukushima Daiichi nuclear power plant in Japan. Quick action by Sandia and its corporate partner UOP, A Honeywell Company, led to rapid licensing and deployment of the technology in Japan, where it continues to be used to clean up cesium contaminated water at the Fukushima power plant.

Rende, Dean; Nenoff, Tina

2013-11-21T23:59:59.000Z

125

Cleaning Contaminated Water at Fukushima  

ScienceCinema (OSTI)

Crystalline Silico-Titanates (CSTs) are synthetic zeolites designed by Sandia National Laboratories scientists to selectively capture radioactive cesium and other group I metals. They are being used for cleanup of radiation-contaminated water at the Fukushima Daiichi nuclear power plant in Japan. Quick action by Sandia and its corporate partner UOP, A Honeywell Company, led to rapid licensing and deployment of the technology in Japan, where it continues to be used to clean up cesium contaminated water at the Fukushima power plant.

Rende, Dean; Nenoff, Tina

2014-02-26T23:59:59.000Z

126

A Near Maximum Likelihood Decoding Algorithm for MIMO Systems ...  

E-Print Network [OSTI]

Jul 30, 2005 ... the randomization procedure of [43], we bijectively map the .... ?1x are also in the integer grid. ... in a Maximum A Posteriori (MAP) decoder by.

2005-10-05T23:59:59.000Z

127

Solving Maximum-Entropy Sampling Problems Using Factored Masks  

E-Print Network [OSTI]

Mar 2, 2005 ... Abstract: We present a practical approach to Anstreicher and Lee's masked spectral bound for maximum-entropy sampling, and we describe ...

Samuel Burer

2005-03-02T23:59:59.000Z

128

A masked spectral bound for maximum-entropy sampling  

E-Print Network [OSTI]

Sep 16, 2003 ... Abstract: We introduce a new masked spectral bound for the maximum-entropy sampling problem. This bound is a continuous generalization of ...

Kurt Anstreicher

2003-09-16T23:59:59.000Z

129

Maximum entropy generation in open systems: the Fourth Law?  

E-Print Network [OSTI]

This paper develops an analytical and rigorous formulation of the maximum entropy generation principle. The result is suggested as the Fourth Law of Thermodynamics.

Umberto Lucia

2010-11-17T23:59:59.000Z

130

analog fixed maximum: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

state for given entanglement which can be viewed as an analogue of the Jaynes maximum entropy principle. Pawel Horodecki; Ryszard Horodecki; Michal Horodecki 1998-05-22...

131

IBM Research Report Solving Maximum-Entropy Sampling ...  

E-Print Network [OSTI]

Feb 28, 2005 ... Solving Maximum-Entropy Sampling Problems Using. Factored Masks. Samuel Burer. Department of Management Sciences. University of Iowa.

2005-02-28T23:59:59.000Z

132

A Requirement for Significant Reduction in the Maximum BTU Input...  

Energy Savers [EERE]

A Requirement for Significant Reduction in the Maximum BTU Input Rate of Decorative Vented Gas Fireplaces Would Impose Substantial Burdens on Manufacturers A Requirement for...

133

Stack Characterization System for Inspection of Contaminated Off-Gas Stacks  

Broader source: Energy.gov [DOE]

The stack characterization system (SCS) is a tele-operated remote system that collects samples and data to characterize the quantitativeand qualitative levels of contamination inside off-gas stacks...

134

Method for refining contaminated iridium  

DOE Patents [OSTI]

Contaminated iridium is refined by alloying it with an alloying agent selected from the group consisting of manganese and an alloy of manganese and copper, and then dissolving the alloying agent from the formed alloy to provide a purified iridium powder.

Heshmatpour, B.; Heestand, R.L.

1982-08-31T23:59:59.000Z

135

Method for refining contaminated iridium  

DOE Patents [OSTI]

Contaminated iridium is refined by alloying it with an alloying agent selected from the group consisting of manganese and an alloy of manganese and copper, and then dissolving the alloying agent from the formed alloy to provide a purified iridium powder.

Heshmatpour, Bahman (Waltham, MA); Heestand, Richard L. (Oak Ridge, TN)

1983-01-01T23:59:59.000Z

136

Electrodic voltages accompanying stimulated bioremediation of a uranium-contaminated aquifer  

SciTech Connect (OSTI)

The inability to track the products of subsurface microbial activity during stimulated bioremediation has limited its implementation. We used spatiotemporal changes in electrodic potentials (EP) to track the onset and persistence of stimulated sulfate-reducing bacteria in a uranium-contaminated aquifer undergoing acetate amendment. Following acetate injection, anomalous voltages approaching -900 mV were measured between copper electrodes within the aquifer sediments and a single reference electrode at the ground surface. Onset of EP anomalies correlated in time with both the accumulation of dissolved sulfide and the removal of uranium from groundwater. The anomalies persisted for 45 days after halting acetate injection. Current-voltage and current-power relationships between measurement and reference electrodes exhibited a galvanic response, with a maximum power density of 10 mW/m{sup 2} during sulfate reduction. We infer that the EP anomalies resulted from electrochemical differences between geochemically reduced regions and areas having higher oxidation potential. Following the period of sulfate reduction, EP values ranged from -500 to -600 mV and were associated with elevated concentrations of ferrous iron. Within 10 days of the voltage decrease, uranium concentrations rebounded from 0.2 to 0.8 {mu}M, a level still below the background value of 1.5 {mu}M. These findings demonstrate that EP measurements provide an inexpensive and minimally invasive means for monitoring the products of stimulated microbial activity within aquifer sediments and are capable of verifying maintenance of redox conditions favorable for the stability of bioreduced contaminants, such as uranium.

Williams, K.H.; N'Guessan, A.L.; Druhan, J.; Long, P.E.; Hubbard, S.S.; Lovley, D.R.; Banfield, J.F.

2009-11-15T23:59:59.000Z

137

Ecotoxicity literature review of selected Hanford Site contaminants  

SciTech Connect (OSTI)

Available information on the toxicity, food chain transport, and bioconcentration of several Hanford Site contaminants were reviewed. The contaminants included cesium-137, cobalt-60, europium, nitrate, plutonium, strontium-90, technetium, tritium, uranium, and chromium (III and VI). Toxicity and mobility in both aquatic and terrestrial systems were considered. For aquatic systems, considerable information was available on the chemical and/or radiological toxicity of most of the contaminants in invertebrate animals and fish. Little information was available on aquatic macrophyte response to the contaminants. Terrestrial animals such as waterfowl and amphibians that have high exposure potential in aquatic systems were also largely unrepresented in the toxicity literature. The preponderance of toxicity data for terrestrial biota was for laboratory mammals. Bioconcentration factors and transfer coefficients were obtained for primary producers and consumers in representative aquatic and terrestrial systems; however, little data were available for upper trophic level transfer, particularly for terrestrial predators. Food chain transport and toxicity information for the contaminants were generally lacking for desert or sage brush-steppe organisms, particularly plants and reptiles

Driver, C.J.

1994-03-01T23:59:59.000Z

138

Maximum Constant Boost Control of the Z-Source Inverter  

E-Print Network [OSTI]

Maximum Constant Boost Control of the Z-Source Inverter Miaosen Shen1 , Jin Wang1 , Alan Joseph1 Laboratory Abstract: This paper proposes two maximum constant boost control methods for the Z-source inverter to modulation index is analyzed in detail and verified by simulation and experiment. Keywords- Z-source inverter

Tolbert, Leon M.

139

Appendix 22 Draft Nutrient Management Plan and Total Maximum Daily  

E-Print Network [OSTI]

Appendix 22 Draft Nutrient Management Plan and Total Maximum Daily Load for Flathead Lake, Montana. #12;11/01/01 DRAFT i October 30, 2001 Draft Nutrient Management Plan and Total Maximum Daily Load..............................................................................................................................2-11 SECTION 3.0 APPLICABLE WATER QUALITY STANDARDS

140

Reliability and Consistency of Surface Contamination Measurements  

SciTech Connect (OSTI)

Surface contamination evaluation is a tough problem since it is difficult to isolate the radiations emitted by the surface, especially in a highly irradiating atmosphere. In that case the only possibility is to evaluate smearable (removeable) contamination since ex-situ countings are possible. Unfortunately, according to our experience at CEA, these values are not consistent and thus non relevant. In this study, we show, using in-situ Fourier Transform Infra Red spectrometry on contaminated metal samples, that fixed contamination seems to be chemisorbed and removeable contamination seems to be physisorbed. The distribution between fixed and removeable contamination appears to be variable. Chemical equilibria and reversible ion exchange mechanisms are involved and are closely linked to environmental conditions such as humidity and temperature. Measurements of smearable contamination only give an indication of the state of these equilibria between fixed and removeable contamination at the time and in the environmental conditions the measurements were made.

Rouppert, F.; Rivoallan, A.; Largeron, C.

2002-02-26T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Emerging contaminants and microorganisms into the environment  

E-Print Network [OSTI]

Workshop Emerging contaminants and microorganisms into the environment: contamination pathways Environmental Engineering Division Surname _____________________Name____________________ Job Environmental Engineering Division (SEED) Department of Civil Engineering University of Salerno Via Ponte don

Costagliola, Gennaro

142

LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL  

SciTech Connect (OSTI)

Controlled landfilling is an approach to manage solid waste landfills, so as to rapidly complete methane generation, while maximizing gas capture and minimizing the usual emissions of methane to the atmosphere. With controlled landfilling, methane generation is accelerated to more rapid and earlier completion to full potential by improving conditions (principally moisture, but also temperature) to optimize biological processes occurring within the landfill. Gas is contained through use of surface membrane cover. Gas is captured via porous layers, under the cover, operated at slight vacuum. A field demonstration project has been ongoing under NETL sponsorship for the past several years near Davis, CA. Results have been extremely encouraging. Two major benefits of the technology are reduction of landfill methane emissions to minuscule levels, and the recovery of greater amounts of landfill methane energy in much shorter times, more predictably, than with conventional landfill practice. With the large amount of US landfill methane generated, and greenhouse potency of methane, better landfill methane control can play a substantial role both in reduction of US greenhouse gas emissions and in US renewable energy. The work described in this report, to demonstrate and advance this technology, has used two demonstration-scale cells of size (8000 metric tons [tonnes]), sufficient to replicate many heat and compaction characteristics of larger ''full-scale'' landfills. An enhanced demonstration cell has received moisture supplementation to field capacity. This is the maximum moisture waste can hold while still limiting liquid drainage rate to minimal and safely manageable levels. The enhanced landfill module was compared to a parallel control landfill module receiving no moisture additions. Gas recovery has continued for a period of over 4 years. It is quite encouraging that the enhanced cell methane recovery has been close to 10-fold that experienced with conventional landfills. This is the highest methane recovery rate per unit waste, and thus progress toward stabilization, documented anywhere for such a large waste mass. This high recovery rate is attributed to moisture, and elevated temperature attained inexpensively during startup. Economic analyses performed under Phase I of this NETL contract indicate ''greenhouse cost effectiveness'' to be excellent. Other benefits include substantial waste volume loss (over 30%) which translates to extended landfill life. Other environmental benefits include rapidly improved quality and stabilization (lowered pollutant levels) in liquid leachate which drains from the waste.

Don Augenstein; Ramin Yazdani; Rick Moore; Michelle Byars; Jeff Kieffer; Professor Morton Barlaz; Rinav Mehta

2000-02-26T23:59:59.000Z

143

Webinar: NREL's Fuel Cell Contaminant Database  

Broader source: Energy.gov [DOE]

Video recording and text version of the webinar titled "NREL's Fuel Cell Contaminant Database," originally presented on May 27, 2014.

144

Long-Term Recovery of PCB-Contaminated Surface Sediments at the Sangamo-Weston / Twelvemile Creek / Lake Hartwell Superfund Site  

SciTech Connect (OSTI)

Natural recovery of contaminated sediments relies on burial of contaminated sediments with increasingly clean sediments over time (i.e., natural capping). Natural capping reduces the risk of resuspension of contaminated surface sediments, and it reduces the potential for contaminant transport into the food chain by limiting bioturbation of contaminated surface or near-surface sediments. This study evaluated the natural recovery of surface sediments contaminated with polychlorinated biphenyls (PCBs) at the Sangamo-Weston/Twelvemile Creek/Lake Hartwell Superfund Site (Lake Hartwell), Pickens County, SC. The primary focus was on sediment recovery resulting from natural capping processes. Total PCB (t-PCB), lead-210 (210Pb), and cesium-137 (137Cs) sediment core profiles were used to establish vertical t-PCB concentration profiles, age date sediments, and determine surface sedimentation and surface sediment recovery rates in 18 cores collected along 10 transects. Four upgradient transects in the headwaters of Lake Hartwell were impacted by historical sediment releases from three upgradient sediment impoundments. These transects were characterized by silt/ clay and sand layering. The highest PCB concentrations were associated with silt/clay layers (1.8-3.5% total organic carbon (TOC)), while sand layers (0.05-0.32% TOC) contained much lower PCB concentrations. The historical sediment releases resulted in substantial burial of PCBcontaminated sediment in the vicinity of these four cores; each core contained less than 1 mg/kg t-PCBs in the surface sand layers. Cores collected from six downgradient Lake Hartwell transects consisted primarily of silt and clay (0.91-5.1% TOC) and were less noticeably impacted by the release of sand from the impoundments. Vertical t-PCB concentration profiles in these cores began with relatively low PCB concentrations at the sediment-water interface and increased in concentration with depth until maximum PCB concentrations were measured at _30-60 cm below the sediment-water interface, ca. 1960-1980. Maximum t-PCB concentrations were followed by progressively decreasing concentrations with depth until the t-PCB concentrations approached the detection limit, where sediments were likely deposited before the onset of PCB use at the Sangamo-Weston plant. The sediments containing the maximum PCB concentrations are associated with the period of maximum PCB release into the watershed. Sedimentation rates averaged 2.1 ( 1.5 g/(cm2 yr) for 12 of 18 cores collected. The 1994 Record of Decision cleanup requirement is 1.0 mg/kg; two more goals (0.4 and 0.05 mg/kg t-PCBs) also were identified. Average surface sedimentation requirements to meet the three goals were 1.4 ( 3.7, 11 ( 4.2, and 33 ( 11 cm, respectively. Using the age dating results, the average recovery dates to meet these goals were 2000.6 ( 2.7, 2007.4 ( 3.5, and 2022.7 ( 11 yr, respectively. (The 95% prediction limits for these values also are provided.) Despite the reduction in surface sediment PCB concentrations, PCB concentrations measured in largemouth bass and hybrid bass filets continue to exceed the 2.0 mg/kg FDA fish tolerance level.

Brenner, Richard C.; Magar, Victor S.; Ickes, Jennifer A.; Foote, Eric A.; Abbott, James E.; Bingler, Linda S.; Crecelius, Eric A.

2004-03-10T23:59:59.000Z

145

In situ bioremediation of petrol contaminated groundwater  

E-Print Network [OSTI]

) Bacterial Diversity and Aerobic Biodegradation Potential in a BTEX-Contaminated Aquifer Water Air Soil21/11/08 1 In situ bioremediation of petrol contaminated groundwater Guido Miguel Delgadillo EVS and facts · Likelihood of contamination · Benefits of in situ bioremediation So... Ask not what groundwater

Blouin-Demers, Gabriel

146

In situ removal of contamination from soil  

DOE Patents [OSTI]

A process of remediation of cationic heavy metal contamination from soil utilizes gas phase manipulation to inhibit biodegradation of a chelating agent that is used in an electrokinesis process to remove the contamination. The process also uses further gas phase manipulation to stimulate biodegradation of the chelating agent after the contamination has been removed. The process ensures that the chelating agent is not attacked by bioorganisms in the soil prior to removal of the contamination, and that the chelating agent does not remain as a new contaminant after the process is completed. 5 figs.

Lindgren, E.R.; Brady, P.V.

1997-10-14T23:59:59.000Z

147

In situ removal of contamination from soil  

DOE Patents [OSTI]

A process of remediation of cationic heavy metal contamination from soil utilizes gas phase manipulation to inhibit biodegradation of a chelating agent that is used in an electrokinesis process to remove the contamination, and further gas phase manipulation to stimulate biodegradation of the chelating agent after the contamination has been removed. The process ensures that the chelating agent is not attacked by bioorganisms in the soil prior to removal of the contamination, and that the chelating agent does not remain as a new contaminant after the process is completed.

Lindgren, Eric R. (Albuquerque, NM); Brady, Patrick V. (Albuquerque, NM)

1997-01-01T23:59:59.000Z

148

Linearized semiclassical initial value time correlation functions with maximum entropy analytic continuation  

E-Print Network [OSTI]

1992). J. Skilling, in Maximum entropy and Bayesian methods,1989). S. F. Gull, in Maximum entropy and Bayesian methods,with the classical maximum entropy (CME) technique (MEAC-

Liu, Jian

2008-01-01T23:59:59.000Z

149

Improved constraints on transit time distributions from argon 39: A maximum entropy approach  

E-Print Network [OSTI]

Gull (1991), Bayesian maximum entropy image reconstruction,Atlantic venti- lated? Maximum entropy inversions of bottlefrom argon 39: A maximum entropy approach Mark Holzer 1,2

Holzer, Mark; Primeau, Francois W

2010-01-01T23:59:59.000Z

150

Quantum Statistics Basis, Thermodynamic Analogies and the Degree of Confidence for Maximum Entropy Restoration and Estimation  

E-Print Network [OSTI]

of Confidence for Maximum Entropy Restoration and EstimationApril 3, 1992) The Maximum Entropy method, using physicalare discussed. Maximum Entropy (ME) estimation has been

Soffer, Bernard H; Kikuchi, Ryoichi

1994-01-01T23:59:59.000Z

151

On the maximum pressure rise rate in boosted HCCI operation  

E-Print Network [OSTI]

This paper explores the combined effects of boosting, intake air temperature, trapped residual gas fraction, and dilution on the Maximum Pressure Rise Rate (MPRR) in a boosted single cylinder gasoline HCCI engine with ...

Wildman, Craig B.

152

Multichannel Blind Identification: From Subspace to Maximum Likelihood Methods  

E-Print Network [OSTI]

Multichannel Blind Identification: From Subspace to Maximum Likelihood Methods LANG TONG, MEMBER, IEEE, AND SYLVIE PERREAU Invited Paper A review of recent blind channel estimation algorithms is pre-- Blind equalization, parameter estimation, system identification. I. INTRODUCTION A. What Is Blind

Tong, Lang

153

Multi-Class Classification with Maximum Margin Multiple Kernel  

E-Print Network [OSTI]

(named OBSCURE and UFO-MKL, respectively) are used to optimize primal versions of equivalent problems), the OBSCURE and UFO-MKL algorithms are compared against MCMKL #12;Multi-Class Classification with Maximum

Tomkins, Andrew

154

Maximum entropy method and oscillations in the diffraction cone  

E-Print Network [OSTI]

The maximum entropy method has been applied to investigate the oscillating structure in the pbarp- and pp-elastic scattering differential cross-section at high energy and small momentum transfer. Oscillations satisfying quite realistic reliability criteria have been found.

O. Dumbrajs; J. Kontros; A. Lengyel

2000-07-15T23:59:59.000Z

155

Efficiency at maximum power of interacting molecular machines  

E-Print Network [OSTI]

We investigate the efficiency of systems of molecular motors operating at maximum power. We consider two models of kinesin motors on a microtubule: for both the simplified and the detailed model, we find that the many-body exclusion effect enhances the efficiency at maximum power of the many-motor system, with respect to the single motor case. Remarkably, we find that this effect occurs in a limited region of the system parameters, compatible with the biologically relevant range.

N. Golubeva; A. Imparato

2012-10-22T23:59:59.000Z

156

The maximum entropy tecniques and the statistical description of systems  

E-Print Network [OSTI]

The maximum entropy technique (MENT) is used to determine the distribution functions of physical values. MENT naturally combines required maximum entropy, the properties of a system and connection conditions in the form of restrictions imposed on the system. It can, therefore, be employed to statistically describe closed and open systems. Examples in which MENT is used to describe equilibrium and non-equilibrium states, as well as steady states that are far from being in thermodynamic equilibrium, are discussed.

B. Z. Belashev; M. K. Suleymanov

2001-10-19T23:59:59.000Z

157

JV Task 99-Integrated Risk Analysis and Contaminant Reduction, Watford City, North Dakota  

SciTech Connect (OSTI)

The Energy & Environmental Research Center (EERC) conducted a limited site investigation and risk analyses for hydrocarbon-contaminated soils and groundwater at a Construction Services, Inc., site in Watford City, North Dakota. Site investigation confirmed the presence of free product and high concentrations of residual gasoline-based contaminants in several wells, the presence of 1,2-dichloroethane, and extremely high levels of electrical conductivity indicative of brine residuals in the tank area south of the facility. The risk analysis was based on compilation of information from the site-specific geotechnical investigation, including multiphase extraction pilot test, laser induced fluorescence probing, evaluation of contaminant properties, receptor survey, capture zone analysis and evaluation of well head protection area for municipal well field. The project results indicate that the risks associated with contaminant occurrence at the Construction Services, Inc. site are low and, under current conditions, there is no direct or indirect exposure pathway between the contaminated groundwater and soils and potential receptors.

Jaroslav Solc; Barry W. Botnen

2007-05-31T23:59:59.000Z

158

Immobilization of uranium in contaminated soil by natural apatite addition  

SciTech Connect (OSTI)

Available in abstract form only. Full text of publication follows: The goal of this study was to evaluate the effectiveness of Serbian natural mineral apatite as soil additive for reducing the migration of uranium from contaminated sediments. In laboratory study we investigated the sorption properties of domestic apatite upon different experimental conditions, such as pH, adsorbent mass, reaction period, concentration of P{sub 2}O{sub 5} in apatite, solid/liquid ratio. In second part of study, we did the quantification of uranium in soil samples, taken from uranium mine site 'Kalna', by sequential extraction method. The same procedure was, also, used for uranium determination in contaminated soil samples after apatite addition, in order to determine the changes in U distribution in soil fraction. The obtained results showed the significant level of immobilization (96.7%) upon certain conditions. Increase of %P{sub 2}O{sub 5} in apatite and process of mechano-chemical activation led to increase of immobilization capacity from 17.50% till 91.64%. The best results for uranium binding were obtained at pH 5.5 and reaction period 60 days (98.04%) The sequential extraction showed the presence of uranium (48.2%) in potentially available soil fractions, but with the apatite addition uranium content in these fractions decreased (30.64%), what is considering environmental aspect significant fact. In situ immobilization of radionuclide using inexpensive sequestering agents, such as apatite, is very adequate for big contaminated areas of soil with low level of contamination. This investigation study on natural apatite from deposit 'Lisina' Serbia was the first one of this type in our country. Key words: apatite, uranium, immobilization, soil, contamination. (authors)

Mrdakovic Popic, Jelena; Stojanovic, Mirjana; Milosevic, Sinisa; Iles, Deana; Zildzovic, Snezana [Institute for Technology of Nuclear and other Mineral Raw Materials, Franche d' Epere 86, Belgrade (Serbia)

2007-07-01T23:59:59.000Z

159

Closure End States for Facilities, Waste Sites, and Subsurface Contamination  

SciTech Connect (OSTI)

The United States (U.S.) Department of Energy (DOE) manages the largest groundwater and soil cleanup effort in the world. DOE’s Office of Environmental Management (EM) has made significant progress in its restoration efforts at sites such as Fernald and Rocky Flats. However, remaining sites, such as Savannah River Site, Oak Ridge Site, Hanford Site, Los Alamos, Paducah Gaseous Diffusion Plant, Portsmouth Gaseous Diffusion Plant, and West Valley Demonstration Project possess the most complex challenges ever encountered by the technical community and represent a challenge that will face DOE for the next decade. Closure of the remaining 18 sites in the DOE EM Program requires remediation of 75 million cubic yards of contaminated soil and 1.7 trillion gallons of contaminated groundwater, deactivation & decommissioning (D&D) of over 3000 contaminated facilities and thousands of miles of contaminated piping, removal and disposition of millions of cubic yards of legacy materials, treatment of millions of gallons of high level tank waste and disposition of hundreds of contaminated tanks. The financial obligation required to remediate this volume of contaminated environment is estimated to cost more than 7% of the to-go life-cycle cost. Critical in meeting this goal within the current life-cycle cost projections is defining technically achievable end states that formally acknowledge that remedial goals will not be achieved for a long time and that residual contamination will be managed in the interim in ways that are protective of human health and environment. Formally acknowledging the long timeframe needed for remediation can be a basis for establishing common expectations for remedy performance, thereby minimizing the risk of re-evaluating the selected remedy at a later time. Once the expectations for long-term management are in place, remedial efforts can be directed towards near-term objectives (e.g., reducing the risk of exposure to residual contamination) instead of focusing on long-term cleanup requirements. An acknowledgement of the long timeframe for complete restoration and the need for long-term management can also help a site transition from the process of pilot testing different remedial strategies to selecting a final remedy and establishing a long-term management and monitoring approach. This approach has led to cost savings and the more efficient use of resources across the Department of Defense complex and at numerous industrial sites across the U.S. Defensible end states provide numerous benefits for the DOE environmental remediation programs including cost-effective, sustainable long-term monitoring strategies, remediation and site transition decision support, and long-term management of closure sites.

Gerdes, Kurt D.; Chamberlain, Grover S.; Wellman, Dawn M.; Deeb, Rula A.; Hawley, Elizabeth L.; Whitehurst, Latrincy; Marble, Justin

2012-11-21T23:59:59.000Z

160

Bottled drinking water: water contamination from bottle materials (glass, hard PET, soft PET), the influence of colour and acidification  

E-Print Network [OSTI]

Bottled drinking water: water contamination from bottle materials (glass, hard PET, soft PET in glass at pH 3.5). None of the leachates approaches the maximum concentrations for drinking water- QMS) in 294 samples of the same bottled water (predominantly mineral water) sold in the European Union

Filzmoser, Peter

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Conversion of transuranic waste to low level waste by decontamination: a technical and economic evaluation  

SciTech Connect (OSTI)

A study was conducted to evaluate the technical and economic feasibility of using in-situ decontamination techniques to convert glove boxes and other large TRU-contaminated components directly into LLW. The results of the technical evaluation indicate that in-situ decontamination of these types of components to non-TRU levels is technically feasible. Applicable decontamination techniques include electropolishing, hand scrubbing, chemical washes/sprays, strippable coatings and Freon spray-cleaning. The removal of contamination from crevices and other holdup areas remains a problem, but may be solved through further advances in decontamination technology. Also, the increase in the allowable maximum TRU level from 10 nCi/g to 100 nCi/g as defined in DOE Order 5820.2 reduces the removal requirement and facilitates measurement of the remaining quantities. The major emphasis of the study was on a cost/benefit evaluation that included a review and update of previous analyses and evaluations of TRU-waste volume reduction and conversion options. The results of the economic evaluation show, for the assumptions used, that there is a definite cost incentive to size reduce large components, and that decontamination of sectioned material has become cost competitive with the size reduction options. In-situ decontamination appears to be the lowest cost option when based on routine-type operations conducted by well-trained and properly equipped personnel. 16 references, 1 figure, 7 tables.

Allen, R.P.; Hazelton, R.F.

1984-12-01T23:59:59.000Z

162

Radioactive contamination of ZnWO4 crystal scintillators  

E-Print Network [OSTI]

The radioactive contamination of ZnWO4 crystal scintillators has been measured deep underground at the Gran Sasso National Laboratory (LNGS) of the INFN in Italy with a total exposure 3197 kg x h. Monte Carlo simulation, time-amplitude and pulse-shape analyses of the data have been applied to estimate the radioactive contamination of the ZnWO4 samples. One of the ZnWO4 crystals has also been tested by ultra-low background gamma spectrometry. The radioactive contaminations of the ZnWO4 samples do not exceed 0.002 -- 0.8 mBq/kg (depending on the radionuclide), the total alpha activity is in the range: 0.2 - 2 mBq/kg. Particular radioactivity, beta active 65Zn and alpha active 180W, has been detected. The effect of the re-crystallization on the radiopurity of the ZnWO4 crystal has been studied. The radioactive contamination of samples of the ceramic details of the set-ups used in the crystals growth has been checked by low background gamma spectrometry. A project scheme on further improvement of the radiopurity level of the ZnWO4 crystal scintillators is briefly addressed.

P. Belli; R. Bernabei; F. Cappella; R. Cerulli; F. A. Danevich; A. M. Dubovik; S. d'Angelo; E. N. Galashov; B. V. Grinyov; A. Incicchitti; V. V. Kobychev; M. Laubenstein; L. L. Nagornaya; F. Nozzoli; D. V. Poda; R. B. Podviyanuk; O. G. Polischuk; D. Prosperi; V. N. Shlegel; V. I. Tretyak; I. A. Tupitsyna; Ya. V. Vasiliev; Yu. Ya. Vostretsov

2010-09-05T23:59:59.000Z

163

Remediating pesticide contaminated soils using solvent extraction  

SciTech Connect (OSTI)

Bench-scale solvent extraction studies were performed on soil samples obtained from a Superfund site contaminated with high levels of p,p{prime}-DDT, p,p{prime}-DDE and toxaphene. The effectiveness of the solvent extraction process was assessed using methanol and 2-propanol as solvents over a wide range of operating conditions. It was demonstrated that a six-stage methanol extraction using a solvent-to-soil ratio of 1.6 can decrease pesticide levels in the soil by more than 99% and reduce the volume of material requiring further treatment by 25 times or more. The high solubility of the pesticides in methanol resulted in rapid extraction rates, with the system reaching quasi-equilibrium state in 30 minutes. The extraction efficiency was influenced by the number of extraction stages, the solvent-to-soil ratio, and the soil moisture content. Various methods were investigated to regenerate and recycle the solvent. Evaporation and solvent stripping are low cost and reliable methods for removing high pesticide concentrations from the solvent. For low concentrations, GAC adsorption may be used. Precipitating and filtering pesticides by adding water to the methanol/pesticide solution was not successful when tested with soil extracts. 26 refs., 10 figs., 6 tabs.

Sahle-Demessie, E.; Meckes, M.C.; Richardson, T.L. [National Management Research Lab., Cincinnati, OH (United States)

1996-12-31T23:59:59.000Z

164

Metal contamination of soils and crops affected by the Chenzhou lead/zinc mine spill (Hunan, China)  

E-Print Network [OSTI]

Metal contamination of soils and crops affected by the Chenzhou lead/zinc mine spill (Hunan, China Avenue Edouard Belin, 31400 Toulouse, France b Department of Environmental Science, Hunan Agricultural polluted with As, Cd, Zn, Pb and Cu. The contamination levels were in the order of GYBNSZYNJTC showing

Mailhes, Corinne

165

Trophic Transfer of Atmospheric and Sedimentary Contaminants into Great Lakes Fish: Control on Ecosystem Scale Response Times  

E-Print Network [OSTI]

Administration (FDA) advisory level is problematic. The persistence of PCBs in Great Lakes fish has led some in the Great Lakes is a natural consequence of internal recycling and continental scale atmospheric exchange atmospheric deposition) and 'in-place' (i.e., recycling from contaminated sediments) sources of contaminants

166

Modeling to Support Groundwater Contaminant Boundaries for the Shoal Underground Nuclear Test  

SciTech Connect (OSTI)

The purpose of this work is to characterize groundwater flow and contaminant transport at the Shoal underground nuclear test through numerical modeling using site-specific hydrologic data. The ultimate objective is the development of a contaminant boundary, a model-predicted perimeter defining the extent of radionuclide-contaminated groundwater from the underground test throughout 1,000 years at a prescribed level of confidence. This boundary will be developed using the numerical models described here, after they are approved for that purpose by DOE and NDEP.

K. Pohlmann; G. Pohll; J. Chapman; A. Hassan; R. Carroll; C. Shirley

2004-03-01T23:59:59.000Z

167

Situ treatment of contaminated groundwater  

DOE Patents [OSTI]

A system for treating dissolved halogenated organic compounds in groundwater that relies upon electrolytically-generated hydrogen to chemically reduce the halogenated compounds in the presence of a suitable catalyst. A direct current is placed across at least a pair, or an array, of electrodes which are housed within groundwater wells so that hydrogen is generated at the cathode and oxygen at the anode. A pump is located within the well housing in which the cathode(s) is(are) located and draws in groundwater where it is hydrogenated via electrolysis, passes through a well-bore treatment unit, and then transported to the anode well(s) for reinjection into the ground. The well-bore treatment involves a permeable cylinder located in the well bore and containing a packed bed of catalyst material that facilitates the reductive dehalogenation of the halogenated organic compounds by hydrogen into environmentally benign species such as ethane and methane. Also, electro-osmatic transport of contaminants toward the cathode also contributes to contaminant mass removal. The only above ground equipment required are the transfer pipes and a direct circuit power supply for the electrodes. The electrode wells in an array may be used in pairs or one anode well may be used with a plurality of cathode wells. The DC current flow between electrode wells may be periodically reversed which controls the formation of mineral deposits in the alkaline cathode well-bore water, as well as to help rejuvenate the catalysis.

McNab, Jr., Walt W. (Concord, CA); Ruiz, Roberto (Tracy, CA); Pico, Tristan M. (Livermore, CA)

2001-01-01T23:59:59.000Z

168

Biogeochemical Processes In Ethanol Stimulated Uranium Contaminated...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

A laboratory incubation experiment was conducted with uranium contaminated subsurface sediment to assess the geochemical and microbial community response to ethanol amendment. A...

169

Accelerated solvent extraction of petroleum contaminated sediments.  

E-Print Network [OSTI]

??Attempts have been made in recent years to find acceptable alternatives to classical soxhlet extraction of petroleum contaminated sediments. One such method that is very… (more)

Bauguss, Jeffery Lynn

2012-01-01T23:59:59.000Z

170

NGC2613, 3198, 6503, 7184: Case studies against `maximum' disks  

E-Print Network [OSTI]

Decompositions of the rotation curves of NGC2613, 3198, 6505, and 7184 are analysed. For these galaxies the radial velocity dispersions of the stars have been measured and their morphology is clearly discernible. If the parameters of the decompositions are chosen according to the `maximum' disk hypothesis, the Toomre Q stability parameter is systematically less than one and the multiplicities of the spiral arms as expected from density wave theory are inconsitent with the observed morphologies of the galaxies. The apparent Q<1 instability, in particular, is a strong argument against the `maximum' disk hypothesis.

B. Fuchs

1998-12-02T23:59:59.000Z

171

Efficiency of autonomous soft nano-machines at maximum power  

E-Print Network [OSTI]

We consider nano-sized artificial or biological machines working in steady state enforced by imposing non-equilibrium concentrations of solutes or by applying external forces, torques or electric fields. For unicyclic and strongly coupled multicyclic machines, efficiency at maximum power is not bounded by the linear response value 1/2. For strong driving, it can even approach the thermodynamic limit 1. Quite generally, such machines fall in three different classes characterized, respectively, as "strong and efficient", "strong and inefficient", and "balanced". For weakly coupled multicyclic machines, efficiency at maximum power has lost any universality even in the linear response regime.

Udo Seifert

2010-11-11T23:59:59.000Z

172

When are microcircuits well-modeled by maximum entropy methods?  

E-Print Network [OSTI]

POSTER PRESENTATION Open Access When are microcircuits well-modeled by maximum entropy methods? Andrea K Barreiro1*, Eric T Shea-Brown1, Fred M Rieke2,3, Julijana Gjorgjieva4 From Nineteenth Annual Computational Neuroscience Meeting: CNS*2010 San... Antonio, TX, USA. 24-30 July 2010 Recent experiments in retina and cortex have demon- strated that pairwise maximum entropy (PME) methods can approximate observed spiking patterns to a high degree of accuracy [1,2]. In this paper we examine...

2010-07-20T23:59:59.000Z

173

Valence quark distributions of the proton from maximum entropy approach  

E-Print Network [OSTI]

We present an attempt of maximum entropy principle to determine valence quark distributions in the proton at very low resolution scale $Q_0^2$. The initial three valence quark distributions are obtained with limited dynamical information from quark model and QCD theory. Valence quark distributions from this method are compared to the lepton deep inelastic scattering data, and the widely used CT10 and MSTW08 data sets. The obtained valence quark distributions are consistent with experimental observations and the latest global fits of PDFs. Maximum entropy method is expected to be particularly useful in the case where relatively little information from QCD calculation is given.

Rong Wang; Xurong Chen

2014-10-14T23:59:59.000Z

174

Valence quark distributions of the proton from maximum entropy approach  

E-Print Network [OSTI]

We present an attempt of maximum entropy principle to determine valence quark distributions in the proton at very low resolution scale $Q_0^2$. The initial three valence quark distributions are obtained with limited dynamical information from quark model and QCD theory. Valence quark distributions from this method are compared to the lepton deep inelastic scattering data, and the widely used CT10 and MSTW08 data sets. The obtained valence quark distributions are consistent with experimental observations and the latest global fits of PDFs. Maximum entropy method is expected to be particularly useful in the case where relatively little information from QCD calculation is given.

Wang, Rong

2014-01-01T23:59:59.000Z

175

Assessing complexity by means of maximum entropy models  

E-Print Network [OSTI]

We discuss a characterization of complexity based on successive approximations of the probability density describing a system by means of maximum entropy methods, thereby quantifying the respective role played by different orders of interaction. This characterization is applied on simple cellular automata in order to put it in perspective with the usual notion of complexity for such systems based on Wolfram classes. The overlap is shown to be good, but not perfect. This suggests that complexity in the sense of Wolfram emerges as an intermediate regime of maximum entropy-based complexity, but also gives insights regarding the role of initial conditions in complexity-related issues.

Chliamovitch, Gregor; Velasquez, Lino

2014-01-01T23:59:59.000Z

176

Screening of contaminants in Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee. Environmental Restoration Program  

SciTech Connect (OSTI)

Waste Area Grouping 2 (WAG 2) of the Oak Ridge National Laboratory (ORNL) is located in the White Oak Creek Watershed and is composed of White Oak Creek Embayment, White Oak Lake and associated floodplain, and portions of White Oak Creek (WOC) and Melton Branch downstream of ORNL facilities. Contaminants leaving other ORNL WAGs in the WOC watershed pass through WAG 2 before entering the Clinch River. Health and ecological risk screening analyses were conducted on contaminants in WAG 2 to determine which contaminants were of concern and would require immediate consideration for remedial action and which contaminants could be assigned a low priority or further study. For screening purposes, WAG 2 was divided into four geographic reaches: Reach 1, a portion of WOC; Reach 2, Melton Branch; Reach 3, White Oak Lake and the floodplain area to the weirs on WOC and Melton Branch; and Reach 4, the White Oak Creek Embayment, for which an independent screening analysis has been completed. Screening analyses were conducted using data bases compiled from existing data on carcinogenic and noncarcinogenic contaminants, which included organics, inorganics, and radionuclides. Contaminants for which at least one ample had a concentration above the level of detection were placed in a detectable contaminants data base. Those contaminants for which all samples were below the level of detection were placed in a nondetectable contaminants data base.

Blaylock, B.G.; Frank, M.L.; Hoffman, F.O.; Hook, L.A.; Suter, G.W.; Watts, J.A.

1992-07-01T23:59:59.000Z

177

A Benchmarking Analysis for Five Radionuclide Vadose Zone Models (Chain, Multimed{_}DP, Fectuz, Hydrus, and Chain 2D) in Soil Screening Level Calculations  

SciTech Connect (OSTI)

Five vadose zone models with different degrees of complexity (CHAIN, MULTIMED{_}DP, FECTUZ, HYDRUS, and CHAIN 2D) were selected for use in radionuclide soil screening level (SSL) calculations. A benchmarking analysis between the models was conducted for a radionuclide ({sup 99}Tc) release scenario at the Las Cruces Trench Site in New Mexico. Sensitivity of three model outputs to the input parameters were evaluated and compared among the models. The three outputs were peak contaminant concentrations, time to peak concentrations at the water table, and time to exceed the contaminants maximum critical level at a representative receptor well. Model parameters investigated include soil properties such as bulk density, water content, soil water retention parameters and hydraulic conductivity. Chemical properties examined include distribution coefficient, radionuclide half-life, dispersion coefficient, and molecular diffusion. Other soil characteristics, such as recharge rate, also were examined. Model sensitivity was quantified in the form of sensitivity and relative sensitivity coefficients. Relative sensitivities were used to compare the sensitivities of different parameters. The analysis indicates that soil water content, recharge rate, saturated soil water content, and soil retention parameter, {beta}, have a great influence on model outputs. In general, the results of sensitivities and relative sensitivities using five models are similar for a specific scenario. Slight differences were observed in predicted peak contaminant concentrations due to different mathematical treatment among models. The results of benchmarking and sensitivity analysis would facilitate the model selection and application of the model in SSL calculations.

Chen, J-S.; Drake, R.; Lin, Z.; Jewett, D. G.

2002-02-26T23:59:59.000Z

178

A methodology for estimating the residual contamination contribution to the source term in a spent-fuel transport cask  

SciTech Connect (OSTI)

This report describes the ranges of the residual contamination that may build up in spent-fuel transport casks. These contamination ranges are calculated based on data taken from published reports and from previously unpublished data supplied by cask transporters. The data involve dose rate measurements, interior smear surveys, and analyses of water flushed out of cask cavities during decontamination operations. A methodology has been developed to estimate the effect of residual contamination on spent-fuel cask containment requirements. Factors in estimating the maximum permissible leak rates include the form of the residual contamination; possible release modes; internal gas-borne depletion; and the temperature, pressure, and vibration characteristics of the cask during transport under normal and accident conditions. 12 refs., 9 figs., 4 tabs.

Sanders, T.L. (Sandia National Labs., Albuquerque, NM (United States)); Jordan, H. (EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant); Pasupathi, V. (Battelle, Columbus, OH (United States)); Mings, W.J. (USDOE Idaho Field Office, Idaho Falls, ID (United States)); Reardon, P.C. (GRAM, Inc., Albuquerque, NM (United States))

1991-09-01T23:59:59.000Z

179

Maximum power tracking control scheme for wind generator systems  

E-Print Network [OSTI]

The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

Mena Lopez, Hugo Eduardo

2008-10-10T23:59:59.000Z

180

Maximum power tracking control scheme for wind generator systems  

E-Print Network [OSTI]

The purpose of this work is to develop a maximum power tracking control strategy for variable speed wind turbine systems. Modern wind turbine control systems are slow, and they depend on the design parameters of the turbine and use wind and/or rotor...

Mena, Hugo Eduardo

2009-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Maximum-principle-satisfying and positivity-preserving high order ...  

E-Print Network [OSTI]

conservation laws: Survey and new developments ..... Notice that in (2.10) we need to evaluate the maximum/minimum of a ..... total energy, p is the pressure, e is the internal energy, and ? > 1 is a constant ... under a standard CFL condition.

2011-04-01T23:59:59.000Z

182

Maximum Entropy in Support of Semantically Annotated Datasets  

E-Print Network [OSTI]

Maximum Entropy in Support of Semantically Annotated Datasets Paulo Pinheiro da Silva, Vladik whether two datasets describe the same quantity. The existing solution to this problem is to use these datasets' ontologies to deduce that these datasets indeed represent the same quantity. However, even when

Kreinovich, Vladik

183

Performance of Civil Aviation Receivers during Maximum Solar Activity Events  

E-Print Network [OSTI]

Performance of Civil Aviation Receivers during Maximum Solar Activity Events Lina DEAMBROGIO on the fields of ionosphere scintillations, solar energetic particles and on the implementation of operational the upcoming period of high solar activity. Emilien ROBERT got his PhD in 2005 and started to work on behalf

Boyer, Edmond

184

Rapidly Solving an Online Sequence of Maximum Flow Problems  

E-Print Network [OSTI]

... an interdictor allocates a finite amount of resources to remove arcs from a net- ... is, the next maximum flow problem in the sequence differs from the previous one by ..... the appropriate reoptimization case and then taking the appropriate action to ..... Our first set of computational experiments tested the performance of our ...

2008-02-29T23:59:59.000Z

185

THE MAXIMUM CAPACITY OF A LINE PLAN IS INAPPROXIMABLE  

E-Print Network [OSTI]

THE MAXIMUM CAPACITY OF A LINE PLAN IS INAPPROXIMABLE CHRISTINA PUHL AND SEBASTIAN STILLER Abstract a network, upper arc-capacities and a line pool. E-mail: puhl@math.tu-berlin.de, stiller of the European Commission under contract no. FP6-021235-2. 1 #12;2 CHRISTINA PUHL AND SEBASTIAN STILLER We

Nabben, Reinhard

186

O(1)-Approximations for Maximum Movement Piotr Berman1  

E-Print Network [OSTI]

movement of the pebbles, motivated by minimizing either execution time or energy usage. Spe- cific problems the maximum movement made by pebbles on a graph to reach a configuration in which the pebbles form a connected. For example, in the connectivity goal, the proximity of the robots should form a connected graph. Two

Demaine, Erik

187

Maximization of Recursive Utilities: A Dynamic Maximum Principle Approach  

E-Print Network [OSTI]

Maximization of Recursive Utilities: A Dynamic Maximum Principle Approach Wahid FAIDI LAMSIN, ENIT for a class of robust utility function introduced in Bordigoni, Matoussi et Schweizer (2005). Our method-investment strategy which is characterized as the unique solution of a forward-backward system. Key words : Utility

Di Girolami, Cristina

188

Maximum stellar mass versus cluster membership number revisited  

E-Print Network [OSTI]

We have made a new compilation of observations of maximum stellar mass versus cluster membership number from the literature, which we analyse for consistency with the predictions of a simple random drawing hypothesis for stellar mass selection in clusters. Previously, Weidner and Kroupa have suggested that the maximum stellar mass is lower, in low mass clusters, than would be expected on the basis of random drawing, and have pointed out that this could have important implications for steepening the integrated initial mass function of the Galaxy (the IGIMF) at high masses. Our compilation demonstrates how the observed distribution in the plane of maximum stellar mass versus membership number is affected by the method of target selection; in particular, rather low n clusters with large maximum stellar masses are abundant in observational datasets that specifically seek clusters in the environs of high mass stars. Although we do not consider our compilation to be either complete or unbiased, we discuss the method by which such data should be statistically analysed. Our very provisional conclusion is that the data is not indicating any striking deviation from the expectations of random drawing.

Th. Maschberger; C. J. Clarke

2008-09-05T23:59:59.000Z

189

Maximum likelihood estimation of the equity Efstathios Avdis  

E-Print Network [OSTI]

premium is usually estimated by taking the sample mean of stock returns and subtracting a measure the expected return on the aggregate stock market less the government bill rate, is of central importance an alternative esti- mator, based on maximum likelihood, that takes into account informa- tion contained

Kahana, Michael J.

190

Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint  

E-Print Network [OSTI]

Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint Zhe Wang Electrical--In this paper, we develop efficient algorithm to obtain the optimal energy schedule for fading channel with energy harvesting. We assume that the side information of both the channel states and energy harvesting

Greenberg, Albert

191

Retrocommissioning Case Study - Applying Building Selection Criteria for Maximum Results  

E-Print Network [OSTI]

RETROCOMMISSIONING CASE STUDY ?Applying Building Selection Criteria for Maximum Results? Larry Luskay, Tudi Haasl, Linda Irvine Portland Energy Conservation, Inc. Portland, Oregon Donald Frey Architectural Energy Corporation Boulder.... The building was retrocommissioned by Portland Energy Conservation, Inc. (PECI), in conjunction with Architectural Energy Corporation (AEC). The building-specific goals were: 1) Obtain cost-effective energy savings from optimizing operation...

Luskay, L.; Haasl, T.; Irvine, L.; Frey, D.

2002-01-01T23:59:59.000Z

192

Biotreatment of groundwater contaminated with MTBE: interaction of common environmental co-contaminants  

E-Print Network [OSTI]

Biotreatment of groundwater contaminated with MTBE: interaction of common environmental co November 2005 Key words: aerobic, biodegradation, BTEX, co-contaminant, MTBE, TBA Abstract Contamination of groundwater with the gasoline additive methyl tert-butyl ether (MTBE) is often accompanied by many aromatic

193

Concluding Remarks In this work, we have explored in depth many types of radioactive contamination that are  

E-Print Network [OSTI]

Concluding Remarks In this work, we have explored in depth many types of radioactive contamination as radiopurity testing facilities, capable of measuring the radioactivity levels of materials to be used

194

Method of removing oxidized contaminants from water  

DOE Patents [OSTI]

The present invention is a method for removing oxidized contaminant(s) from water. More specifically, the invention has the steps of contacting water containing the oxidized contaminant(s) with a layered aluminosilicate having Fe(II). The aluminosilicate may contain naturally occurring Fe(II), or the Fe(II) may be produced by reducing Fe(III) that is initially present. Reduction may be either by exposure to a chemical or biological reductant. Contacting the water containing oxidized contaminant(s) may be by (1) injection of Fe(II)-containing layered aluminosilicate, via a well, into a saturated zone where it is likely to intercept the contaminated water; (2) injection of contaminated water into a vessel containing the Fe(II)-bearing layered aluminosilicate; and (3) first reducing Fe(III) in the layered aluminosilicate to Fe(II) by injection of a biological or chemical reductant, into an aquifer or vessel having sufficient Fe(III)-bearing aluminosilicate to produce the necessary Fe(II). 8 figs.

Amonette, J.E.; Fruchter, J.S.; Gorby, Y.A.; Cole, C.R.; Cantrell, K.J.; Kaplan, D.I.

1998-07-21T23:59:59.000Z

195

Method of removing oxidized contaminants from water  

DOE Patents [OSTI]

The present invention is a method for removing oxidized contaminant(s) from water. More specifically, the invention has the steps of contacting water containing the oxidized contaminant(s) with a layered aluminosilicate having Fe(II). The aluminosilicate may contain naturally occurring Fe(II), or the Fe(II) may be produced by reducing Fe(III) that is initially present. Reduction may be either by exposure to a chemical or biological reductant. Contacting the water containing oxidized contaminant(s) may be by (1) injection of Fe(II)-containing layered aluminosilicate, via a well, into a saturated zone where it is likely to intercept the contaminated water; (2) injection of contaminated water into a vessel containing the Fe(II)-bearing layered aluminosilicate; and (3) first reducing Fe(III) in the layered aluminosilicate to Fe(II) by injection of a biological or chemical reductant, into an aquifer or vessel having sufficient Fe(III)-bearing aluminosilicate to produce the necessary Fe(II).

Amonette, James E. (Richland, WA); Fruchter, Jonathan S. (Richland, WA); Gorby, Yuri A. (Richland, WA); Cole, Charles R. (West Richmond, WA); Cantrell, Kirk J. (West Richmond, WA); Kaplan, Daniel I. (Richland, WA)

1998-01-01T23:59:59.000Z

196

Remediation and Recovery of Uranium from Contaminated  

E-Print Network [OSTI]

Remediation and Recovery of Uranium from Contaminated Subsurface Environments with Electrodes K E L that Geobacter species can effectively remove uranium from contaminated groundwater by reducing soluble U was stably precipitated until reoxidized in the presence of oxygen. When an electrode was placed in uranium

Lovley, Derek

197

Method of removing contaminants from plastic resins  

DOE Patents [OSTI]

A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2008-11-18T23:59:59.000Z

198

Method of removing contaminants from plastic resins  

DOE Patents [OSTI]

A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

Bohnert,George W. (Harrisonville, MO); Hand,Thomas E. (Lee's Summit, MO); Delaurentiis,Gary M. (Jamestown, CA)

2007-08-07T23:59:59.000Z

199

Method for removing contaminants from plastic resin  

DOE Patents [OSTI]

A method for removing contaminants from synthetic resin material containers using a first organic solvent system and a second carbon dioxide system. The organic solvent is utilized for removing the contaminants from the synthetic resin material and the carbon dioxide is used to separate any residual organic solvent from the synthetic resin material.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2008-12-30T23:59:59.000Z

200

Minimizing electrode contamination in an electrochemical cell  

SciTech Connect (OSTI)

An electrochemical cell assembly that is expected to prevent or at least minimize electrode contamination includes one or more getters that trap a component or components leached from a first electrode and prevents or at least minimizes them from contaminating a second electrode.

Kim, Yu Seung; Zelenay, Piotr; Johnston, Christina

2014-12-09T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Scrubbing of contaminants from contaminated air streams with aerogel materials with optional photocatalytic destruction  

SciTech Connect (OSTI)

Disclosed is a method for separating a vaporous or gaseous contaminant from an air stream contaminated therewith. This method includes the steps of: (a) passing said contaminated air into a contact zone in which is disposed an aerogel material capable of selecting adsorbing said contaminant from air and therein contacting said contaminated air with an aerogel material; and (b) withdrawing from said zone, air depleted of said contaminant. For present purposes, "contaminant" means a material not naturally occurring in ambient air and/or a material naturally occurring in air but present at a concentration above that found in ambient air. Thus, the present invention scrubs (or treats) air for the purpose of returning it to its ambient composition. Also disclosed herein is a process for the photocatalytic destruction of contaminants from an air stream wherein the contaminated air stream is passed into a control cell or contact zone in which is disposed a photocatalytic aerogel and exposing said aerogel to ultraviolet (UV) radiation for photocatalytically destroying the adsorbed contaminant, and withdrawing from said cell an exhaust air stream depleted in said contaminant.

Attia, Yosry A. (221 Oakland Park Ave., Columbus, OH 43214)

2000-01-01T23:59:59.000Z

202

Maximum Entropy Principle and the Higgs Boson Mass  

E-Print Network [OSTI]

A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.

Alves, Alexandre; da Silva, Roberto

2014-01-01T23:59:59.000Z

203

Maximum Entropy Principle and the Higgs Boson Mass  

E-Print Network [OSTI]

A successful connection between Higgs boson decays and the Maximum Entropy Principle is presented. Based on the information theory inference approach we determine the Higgs boson mass as $M_H= 125.04\\pm 0.25$ GeV, a value fully compatible to the LHC measurement. This is straightforwardly obtained by taking the Higgs boson branching ratios as the target probability distributions of the inference, without any extra assumptions beyond the Standard Model. Yet, the principle can be a powerful tool in the construction of any model affecting the Higgs sector. We give, as an example, the case where the Higgs boson has an extra invisible decay channel. Our findings suggest that a system of Higgs bosons undergoing a collective decay to Standard Model particles is among the most fundamental ones where the Maximum Entropy Principle applies.

Alexandre Alves; Alex G. Dias; Roberto da Silva

2014-11-18T23:59:59.000Z

204

A reliable, fast and low cost maximum power point tracker for photovoltaic applications  

SciTech Connect (OSTI)

This work presents a new maximum power point tracker system for photovoltaic applications. The developed system is an analog version of the ''P and O-oriented'' algorithm. It maintains its main advantages: simplicity, reliability and easy practical implementation, and avoids its main disadvantages: inaccurateness and relatively slow response. Additionally, the developed system can be implemented in a practical way at a low cost, which means an added value. The system also shows an excellent behavior for very fast variables in incident radiation levels. (author)

Enrique, J.M.; Andujar, J.M.; Bohorquez, M.A. [Departamento de Ingenieria Electronica, de Sistemas Informaticos y Automatica, Universidad de Huelva (Spain)

2010-01-15T23:59:59.000Z

205

Maximum entanglement in squeezed boson and fermion states  

SciTech Connect (OSTI)

A class of squeezed boson and fermion states is studied with particular emphasis on the nature of entanglement. We first investigate the case of bosons, considering two-mode squeezed states. Then we construct the fermion version to show that such states are maximum entangled, for both bosons and fermions. To achieve these results, we demonstrate some relations involving squeezed boson states. The generalization to the case of fermions is made by using Grassmann variables.

Khanna, F. C. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Malbouisson, J. M. C. [Instituto de Fisica, Universidade Federal da Bahia, 40210-340, Salvador, BA (Brazil); Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Santana, A. E. [Instituto de Fisica, Universidade de Brasilia, 70910-900, Brasilia, DF (Brazil); Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Santos, E. S. [Centro Federal de Educacao Tecnologica da Bahia, 40030-010, Salvador, BA (Brazil)

2007-08-15T23:59:59.000Z

206

Maximum Entry and Mandatory Separation Ages for Certain Security Employees  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The policy establishes the DOE policy on maximum entry and mandatory separation ages for primary or secondary positions covered under special statutory retirement provisions and for those employees whose primary duties are the protection of officials of the United States against threats to personal safety or the investigation, apprehension, and detention of individuals suspected or convicted of offenses against the criminal laws of the United States. Admin Chg 1, dated 12-1-11, cancels DOE P 310.1.

2001-10-11T23:59:59.000Z

207

Maximum entropy method for reconstruction of the CMB images  

E-Print Network [OSTI]

We propose a new approach for the accurate reconstruction of cosmic microwave background distributions from observations containing in addition to the primary fluctuations the radiation from unresolved extragalactic point sources and pixel noise. The approach uses some effective realizations of the well-known maximum entropy method and principally takes into account {\\it a priori} information about finiteness and spherical symmetry of the power spectrum of the CMB satisfying the Gaussian statistics.

A. T. Bajkova

2002-05-21T23:59:59.000Z

208

Occam's Razor Cuts Away the Maximum Entropy Principle  

E-Print Network [OSTI]

I show that the maximum entropy principle can be replaced by a more natural assumption, that there exists a phenomenological function of entropy consistent with the microscopic model. The requirement of existence provides then a unique construction of the related probability density. I conclude the letter with an axiomatic formulation of the notion of entropy, which is suitable for exploration of the non-equilibrium phenomena.

Rudnicki, ?ukasz

2014-01-01T23:59:59.000Z

209

PNNL: A Supervised Maximum Entropy Approach to Word Sense Disambiguation  

SciTech Connect (OSTI)

In this paper, we described the PNNL Word Sense Disambiguation system as applied to the English All-Word task in Se-mEval 2007. We use a supervised learning approach, employing a large number of features and using Information Gain for dimension reduction. Our Maximum Entropy approach combined with a rich set of features produced results that are significantly better than baseline and are the highest F-score for the fined-grained English All-Words subtask.

Tratz, Stephen C.; Sanfilippo, Antonio P.; Gregory, Michelle L.; Chappell, Alan R.; Posse, Christian; Whitney, Paul D.

2007-06-23T23:59:59.000Z

210

Some interesting consequences of the maximum entropy production principle  

SciTech Connect (OSTI)

Two nonequilibrium phase transitions (morphological and hydrodynamic) are analyzed by applying the maximum entropy production principle. Quantitative analysis is for the first time compared with experiment. Nonequilibrium crystallization of ice and laminar-turbulent flow transition in a circular pipe are examined as examples of morphological and hydrodynamic transitions, respectively. For the latter transition, a minimum critical Reynolds number of 1200 is predicted. A discussion of this important and interesting result is presented.

Martyushev, L. M. [Russian Academy of Sciences, Institute of Industrial Ecology, Ural Division (Russian Federation)], E-mail: mlm@ecko.uran.ru

2007-04-15T23:59:59.000Z

211

Complexity of Groundwater Contaminants at DOE Sites  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) is responsible for the remediation and long-term stewardship of one of the world's largest groundwater contamination portfolios, with a significant number of plumes containing various contaminants, and considerable total mass and activity. As of 1999, the DOE's Office of Environmental Management was responsible for remediation, waste management, or nuclear materials and facility stabilization at 144 sites in 31 states and one U.S. territory, out of which 109 sites were expected to require long-term stewardship. Currently, 19 DOE sites are on the National Priority List. The total number of contaminated plumes on DOE lands is estimated to be 10,000. However, a significant number of DOE sites have not yet been fully characterized. The most prevalent contaminated media are groundwater and soil, although contaminated sediment, sludge, and surface water also are present. Groundwater, soil, and sediment contamination are present at 72% of all DOE sites. A proper characterization of the contaminant inventory at DOE sites is critical for accomplishing one of the primary DOE missions -- planning basic research to understand the complex physical, chemical, and biological properties of contaminated sites. Note that the definitions of the terms 'site' and 'facility' may differ from one publication to another. In this report, the terms 'site,' 'facility' or 'installation' are used to identify a contiguous land area within the borders of a property, which may contain more than one plume. The term 'plume' is used here to indicate an individual area of contamination, which can be small or large. Even though several publications and databases contain information on groundwater contamination and remediation technologies, no statistical analyses of the contaminant inventory at DOE sites has been prepared since the 1992 report by Riley and Zachara. The DOE Groundwater Data Base (GWD) presents data as of 2003 for 221 groundwater plumes at 60 DOE sites and facilities. Note that Riley and Zachara analyzed the data from only 18 sites/facilities including 91 plumes. In this paper, we present the results of statistical analyses of the data in the GWD as guidance for planning future basic and applied research of groundwater contaminants within the DOE complex. Our analyses include the evaluation of a frequency and ranking of specific contaminants and contaminant groups, contaminant concentrations/activities and total contaminant masses and activities. We also compared the results from analyses of the GWD with those from the 1992 report by Riley and Zachara. The difference between our results and those summarized in the 1992 report by Riley and Zachara could be caused by not only additional releases, but also by the use of modern site characterization methods, which more accurately reveal the extent of groundwater contamination. Contaminated sites within the DOE complex are located in all major geographic regions of the United States, with highly variable geologic, hydrogeologic, soil, and climatic conditions. We assume that the information from the 60 DOE sites included in the GWD are representative for the whole DOE complex. These 60 sites include the major DOE sites and facilities, such as Rocky Flats Environmental Technology Site, Colorado; Idaho National Laboratory, Idaho; Savannah River Site, South Carolina; Oak Ridge Reservation, Tennessee; and Hanford Reservation, Washington. These five sites alone ccount for 71% of the value of the remediation work.

Hazen, T.C.; Faybishenko, B.; Jordan, P.

2010-12-03T23:59:59.000Z

212

Assessing inhalation exposure from airborne soil contaminants  

SciTech Connect (OSTI)

A method of estimation of inhalation exposure to airborne soil contaminants is presented. this method is derived from studies of airborne soil particles with radioactive tags. The concentration of contaminants in air (g/m{sup 3}) can be derived from the product of M, the suspended respirable dust mass concentration (g/m{sup 3}), S, the concentration of contaminant in the soil (g/g), and E{sub f}, an enhancement factor. Typical measurement methods and values of M, and E{sub f} are given along with highlights of experiences with this method.

Shinn, J.H.

1998-04-01T23:59:59.000Z

213

Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensembles out-of-equilibrium  

E-Print Network [OSTI]

1957). J. Skilling, in Maximum Entropy and Bayesian Methods,45–52. J. Skilling, in Maximum Entropy and Bayesian Methods,e C. C. Rodriguez, in Maximum Entropy and Bayesian Methods,

Crooks, Gavin E.

2006-01-01T23:59:59.000Z

214

Deriving the continuity of maximum-entropy basis functions via variational analysis  

E-Print Network [OSTI]

and V. J. DellaPietra, A maximum entropy approach to naturalJ. and R. K. Bryan, Maximum entropy image reconstruction:Heidelberg, Continuity of maximum-entropy basis functions p

Sukumar, N.; Wets, R. J. -B.

2007-01-01T23:59:59.000Z

215

Microbial Reduction of Intragrain U(VI) in Contaminated Sediment...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Intragrain U(VI) in Contaminated Sediment. Microbial Reduction of Intragrain U(VI) in Contaminated Sediment. Abstract: The accessibility of precipitated, intragrain U(VI) in a...

216

Geochemical Controls on Contaminant Uranium in Vadose Hanford...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Controls on Contaminant Uranium in Vadose Hanford Formation Sediments at the 200 Area and 300 Area, Hanford Site, Geochemical Controls on Contaminant Uranium in Vadose Hanford...

217

Civil and Environmental Engineering CSU Center for Contaminant Hydrology  

E-Print Network [OSTI]

Civil and Environmental Engineering CSU ­ Center for Contaminant Hydrology Coordinator The Center for Contaminant Hydrology (CCH) ( HYPERLINK "http://www.engr.colostate.edu/CCH/" www

218

Perched-Water Analysis Related to Deep Vadose Zone Contaminant...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Perched-Water Analysis Related to Deep Vadose Zone Contaminant Transport and Impact to Groundwater. Perched-Water Analysis Related to Deep Vadose Zone Contaminant Transport and...

219

Remediation of Mercury and Industrial Contaminants Applied Field...  

Office of Environmental Management (EM)

Remediation of Mercury and Industrial Contaminants Applied Field Research Initiative (RoMIC-AFRI) Remediation of Mercury and Industrial Contaminants Applied Field Research...

220

Uranium-contaminated soils: Ultramicrotomy and electron beam analysis  

SciTech Connect (OSTI)

Uranium contaminated soils from the Fernald Operation Site, Ohio, have been examined by a combination of optical microscopy, scanning electron microscopy with backscattered electron detection (SEM/BSE), and analytical electron microscopy (AEM). A method is described for preparing of transmission electron microscopy (TEM) thin sections by ultramicrotomy. By using these thin sections, SEM and TEM images can be compared directly. Uranium was found in iron oxides, silicates (soddyite), phosphates (autunites), and fluorite. Little uranium was associated with clays. The distribution of uranium phases was found to be inhomogeneous at the microscopic level.

Buck, E.C.; Dietz, N.L.; Bates, J.K.; Cunnane, J.C.

1994-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Maximum Achievable Control Technology for New Industrial Boilers (released in AEO2005)  

Reports and Publications (EIA)

As part of Clean Air Act 90 (CAAA90, the EPA on February 26, 2004, issued a final rulethe National Emission Standards for Hazardous Air Pollutants (NESHAP) to reduce emissions of hazardous air pollutants (HAPs) from industrial, commercial, and institutional boilers and process heaters. The rule requires industrial boilers and process heaters to meet limits on HAP emissions to comply with a Maximum Achievable Control Technology (MACT) floor level of control that is the minimum level such sources must meet to comply with the rule. The major HAPs to be reduced are hydrochloric acid, hydrofluoric acid, arsenic, beryllium, cadmium, and nickel. The EPA predicts that the boiler MACT rule will reduce those HAP emissions from existing sources by about 59,000 tons per year in 2005.

2005-01-01T23:59:59.000Z

222

Method of treating fluoride contaminated wastes  

SciTech Connect (OSTI)

A method for treating spent aluminum smelting potliner material containing fluoride contaminants is described which comprises: adding silica to the material to form a mixture thereof; elevating the temperature of the mixture within the range of 1,000/sup 0/ to 1,700/sup 0/C. to form a slag; providing sufficient silica in the mixture and forming the slag in the presence of sufficient water for pyrohydrolysis conditions resulting in the volatilization of substantially all of the fluoride contaminants mostly in the form of hydrogen fluoride; and cooling the slag remaining after volatilizatiion of substantially all of the fluoride contaminants to produce an insoluble silicate glass-residue containing any remaining portion of the fluoride contaminants in an immobile state.

Davis, P.K.; Kakaria, V.K.

1988-04-05T23:59:59.000Z

223

DIAGNOSTIC ASSESSMENT 2 OF CONTAMINATED SITE PROBLEMS  

E-Print Network [OSTI]

in the environment and undergo complex interactions in more than one environmental medium. Contaminated sites should released into the environment will be controlled by a complex set of processes (such as intermedia

Ma, Lena

224

Modelling Bioremediation of Uranium Contaminated Aquifers   

E-Print Network [OSTI]

Radionuclide extraction, processing and storage have resulted in a legacy of radionuclide-contaminated groundwater aquifers worldwide. An emerging remediation technology for such sites is the in situ immobilisation of ...

Rotter, Ben E G

2008-01-01T23:59:59.000Z

225

Estimating exposure of terrestrial wildlife to contaminants  

SciTech Connect (OSTI)

This report describes generalized models for the estimation of contaminant exposure experienced by wildlife on the Oak Ridge Reservation. The primary exposure pathway considered is oral ingestion, e.g. the consumption of contaminated food, water, or soil. Exposure through dermal absorption and inhalation are special cases and are not considered hereIN. Because wildlife mobile and generally consume diverse diets and because environmental contamination is not spatial homogeneous, factors to account for variation in diet, movement, and contaminant distribution have been incorporated into the models. To facilitate the use and application of the models, life history parameters necessary to estimate exposure are summarized for 15 common wildlife species. Finally, to display the application of the models, exposure estimates were calculated for four species using data from a source operable unit on the Oak Ridge Reservation.

Sample, B.E.; Suter, G.W. II

1994-09-01T23:59:59.000Z

226

Mitigation of radiation induced surface contamination  

DOE Patents [OSTI]

A process for mitigating or eliminating contamination and/or degradation of surfaces having common, adventitious atmospheric contaminants adsorbed thereon and exposed to radiation. A gas or a mixture of gases is introduced into the environment of a surface(s) to be protected. The choice of the gaseous species to be introduced (typically a hydrocarbon gas, water vapor, or oxygen or mixtures thereof) is dependent upon the contaminant as well as the ability of the gaseous species to bind to the surface to be protected. When the surface and associated bound species are exposed to radiation reactive species are formed that react with surface contaminants such as carbon or oxide films to form volatile products (e.g., CO, CO.sub.2) which desorb from the surface.

Klebanoff, Leonard E. (Dublin, CA); Stulen, Richard H. (Livermore, CA)

2003-01-01T23:59:59.000Z

227

Bioaugmentation of TNT-contaminated soil  

E-Print Network [OSTI]

Microbial transformation of trinitrotoluene (TNT) in phics. contaminated soil was investigated in this research. A Bacillus sp., isolated from soil obtained from an army ammunition facility, was used to enhance the rate of TNT removal over a 360 day...

Bokelmann, Annamarie

1999-01-01T23:59:59.000Z

228

Maximum likelihood reconstruction for the Daya Bay Experiment  

E-Print Network [OSTI]

The Daya Bay Reactor Neutrino experiment is designed to precisely determine the neutrino mixing angle theta13. In this paper, we report a maximum likelihood (ML) method to reconstruct the vertex and energy of events in the anti-neutrino detector, based on a simplified optical model that describes light propagation. We calibrate the key paramters of the optical model with Co60 source, by comparing the predicted charges of the PMTs with the observed charges. With the optimized parameters, the resolution of the vertex reconstruction is about 25cm for Co60 gamma.

Xia Dongmei

2014-03-07T23:59:59.000Z

229

Better Nonlinear Models from Noisy Data: Attractors with Maximum Likelihood  

E-Print Network [OSTI]

A new approach to nonlinear modelling is presented which, by incorporating the global behaviour of the model, lifts shortcomings of both least squares and total least squares parameter estimates. Although ubiquitous in practice, a least squares approach is fundamentally flawed in that it assumes independent, normally distributed (IND) forecast errors: nonlinear models will not yield IND errors even if the noise is IND. A new cost function is obtained via the maximum likelihood principle; superior results are illustrated both for small data sets and infinitely long data streams.

Patrick E. McSharry; Leonard A. Smith

1999-11-30T23:59:59.000Z

230

Application of Maximum Entropy Method to Dynamical Fermions  

E-Print Network [OSTI]

The Maximum Entropy Method is applied to dynamical fermion simulations of the (2+1)-dimensional Nambu-Jona-Lasinio model. This model is particularly interesting because at T=0 it has a broken phase with a rich spectrum of mesonic bound states and a symmetric phase where there are resonances, and hence the simple pole assumption of traditional fitting procedures breaks down. We present results extracted from simulations on large lattices for the spectral functions of the elementary fermion, the pion, the sigma, the massive pseudoscalar meson and the symmetric phase resonances.

Jonathan Clowser; Costas Strouthos

2001-10-16T23:59:59.000Z

231

Improving predictability of time series using maximum entropy methods  

E-Print Network [OSTI]

We discuss how maximum entropy methods may be applied to the reconstruction of Markov processes underlying empirical time series and compare this approach to usual frequency sampling. It is shown that, at least in low dimension, there exists a subset of the space of stochastic matrices for which the MaxEnt method is more efficient than sampling, in the sense that shorter historical samples have to be considered to reach the same accuracy. Considering short samples is of particular interest when modelling smoothly non-stationary processes, for then it provides, under some conditions, a powerful forecasting tool. The method is illustrated for a discretized empirical series of exchange rates.

Gregor Chliamovitch; Alexandre Dupuis; Bastien Chopard; Anton Golub

2014-11-28T23:59:59.000Z

232

Reducing Degeneracy in Maximum Entropy Models of Networks  

E-Print Network [OSTI]

Based on Jaynes's maximum entropy principle, exponential random graphs provide a family of principled models that allow the prediction of network properties as constrained by empirical data. However, their use is often hindered by the degeneracy problem characterized by spontaneous symmetry-breaking, where predictions simply fail. Here we show that degeneracy appears when the corresponding density of states function is not log-concave. We propose a solution to the degeneracy problem for a large class of models by exploiting the nonlinear relationships between the constrained measures to convexify the domain of the density of states. We demonstrate the effectiveness of the method on examples, including on Zachary's karate club network data.

Horvát, Szabolcs; Toroczkai, Zoltán

2014-01-01T23:59:59.000Z

233

Improving predictability of time series using maximum entropy methods  

E-Print Network [OSTI]

We discuss how maximum entropy methods may be applied to the reconstruction of Markov processes underlying empirical time series and compare this approach to usual frequency sampling. It is shown that, at least in low dimension, there exists a subset of the space of stochastic matrices for which the MaxEnt method is more efficient than sampling, in the sense that shorter historical samples have to be considered to reach the same accuracy. Considering short samples is of particular interest when modelling smoothly non-stationary processes, for then it provides, under some conditions, a powerful forecasting tool. The method is illustrated for a discretized empirical series of exchange rates.

Chliamovitch, Gregor; Chopard, Bastien; Golub, Anton

2014-01-01T23:59:59.000Z

234

Method for removing contaminants from plastic resin  

DOE Patents [OSTI]

A resin recycling method that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The method includes receiving the resin in container form. The containers are then ground into resin particles. The particles are exposed to a solvent, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. After separating the particles and the resin, a solvent removing agent is used to remove any residual solvent remaining on the resin particles after separation.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2008-12-09T23:59:59.000Z

235

aid maximum output: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

at a given geographic location. Taking the solar irradiation levels, the ambient temperature, and the Sun's position angles as inputs, a multilayer feed-forward neural network...

236

Ionization and maximum energy of nuclei in shock acceleration theory  

E-Print Network [OSTI]

We study the acceleration of heavy nuclei at SNR shocks when the process of ionization is taken into account. Heavy atoms ($Z_N >$ few) in the interstellar medium which start the diffusive shock acceleration (DSA) are never fully ionized at the moment of injection. The ionization occurs during the acceleration process, when atoms already move relativistically. For typical environment around SNRs the photo-ionization due to the background galactic radiation dominates over Coulomb collisions. The main consequence of ionization is the reduction of the maximum energy which ions can achieve with respect to the standard result of the DSA. In fact the photo-ionization has a timescale comparable to the beginning of the Sedov-Taylor phase, hence the maximum energy is no more proportional to the nuclear charge, as predicted by standard DSA, but rather to the effective ions' charge during the acceleration process, which is smaller than the total nuclear charge $Z_N$. This result can have a direct consequence in the pred...

Morlino, Giovanni

2011-01-01T23:59:59.000Z

237

Fate of Contaminants in Contact with West Valley Grouts  

SciTech Connect (OSTI)

The objective of the work described here is to determine to what extent a variety of contaminants, including fission products, actinides, and RCRA elements are sequestered by the two grout formulations. The conceptual model for this study is as follows: a large mass of grout having been poured into a high-level waste tank is in the process of aging and weathering for thousands of years. The waste remaining in the tank will contain radionuclides and other contaminants, much of which will adhere to tank walls and internal structures. The grout will encapsulate the contaminants. Initially the grout will be well sequestered, but over time rainwater and groundwater will gain access to it. Ultimately, the grout/waste environment will be an open system. In this condition water will move through the grout, exposing it to O{sub 2} and CO{sub 2} from the air and HCO{sub 3}{sup -} from the groundwater. Thus we are considering an oxic environment containing HCO{sub 3}{sup -}. Initially the solubility of many contaminants, but not all, will be constrained by chemistry dominated by the grout, primarily by the high pH, around 11.8. This is controlled and buffered by the portland cement and blast furnace slag components of the grout, which by themselves maintain a solution pH of about 12.5. Slowly the pH will diminish as Ca(OH){sub 2} and KOH dissolve, are carried away by water, and CaCO{sub 3} forms. As these conditions develop, the behavior of these elements comes into question. In our conceptual model, although the grout is formulated to provide some reducing capacity, in order to be conservative this mechanism is not considered. In addition to solubility constraints imposed by pH, the various contaminants may be incorporated into a variety of solid phases. Some may be incorporated into newly forming compounds as the grout sets and cures. Others (like soddyite, (UO{sub 2}){sub 2}SiO{sub 4}(H{sub 2}O){sub 2}) are the result of slower reactions but may become important over time as contaminants are exposed to evolving chemistry in the grout. Still other solid phases may form from reactions between the waste and grout components, not only the cementitious materials, but also the additives used in the grout. Another process that may exert some control on contaminant concentrations is adsorption onto solids within the grout. These may be additives such as the fluorapatite or zeolite that are substantial percentages of the grouts or they may be minerals, typically Ca-Al-Si materials, that form in the grout system as cement sets. In addition, as the grout weathers over time, CaCO{sub 3} minerals, such as calcite and aragonite, will form as a rind on the grout and as a fracture filling mineral. Some contaminants are likely to be incorporated into these minerals, to a greater or lesser extent, as they precipitate. For some elements, such as U, there is a significant literature exploring the incorporation into CaCO{sub 3}, but for others there is essentially no information. This is also the case for much of the chemical regime of the grouts. Initial conditions are at pH values around 12 and information is often sparse.

Fuhrmann,M.; Gillow, J.

2009-07-01T23:59:59.000Z

238

Modelling and Hazard Analysis for Contaminated Sediments Using Stamp Model  

E-Print Network [OSTI]

Modelling and Hazard Analysis for Contaminated Sediments Using Stamp Model Karim Hardy* , Franck or contaminants) of contaminated sediments have become very efficient. These technologies, which are particularly sections. The first describes the Novosol® process for treating contaminated sediments. The second

Boyer, Edmond

239

Method of producing hydrogen, and rendering a contaminated biomass inert  

DOE Patents [OSTI]

A method for rendering a contaminated biomass inert includes providing a first composition, providing a second composition, reacting the first and second compositions together to form an alkaline hydroxide, providing a contaminated biomass feedstock and reacting the alkaline hydroxide with the contaminated biomass feedstock to render the contaminated biomass feedstock inert and further producing hydrogen gas, and a byproduct that includes the first composition.

Bingham, Dennis N. (Idaho Falls, ID) [Idaho Falls, ID; Klingler, Kerry M. (Idaho Falls, ID) [Idaho Falls, ID; Wilding, Bruce M. (Idaho Falls, ID) [Idaho Falls, ID

2010-02-23T23:59:59.000Z

240

Perched-Water Analysis Related to Deep Vadose Zone Contaminant Transport and Impact to Groundwater  

SciTech Connect (OSTI)

Perched-water conditions have been observed in the vadose zone above a fine-grained zone that is located just a few meters above the water table beneath the B-complex at the Hanford Site. The perched water, containing elevated concentrations of uranium and technetium-99, is important to consider in evaluating the future flux of contaminated water into the groundwater. A study was conducted to examine the perched-water conditions and quantitatively evaluate 1) factors that control perching behavior, 2) contaminant flux toward groundwater, and, 3) associated groundwater impact. Based on the current vertical transport pathways and large areal extent of the perched system, the evaluation was conducted using a one-dimensional (1-D) analysis. Steady-state scoping calculations showed that the perching-layer hydraulic conductivity is likely to be up to two orders of magnitude less than the base case value obtained from Hanford site literature. Numerical flow and transport simulations provided both steady-state and transient system estimates of water and contaminant behavior and were used to further refine the range of conditions consistent with current observations of perched water height and to provide estimates of future water and contaminant flux to groundwater. With a recharge rate of 6 cm/yr, representative of current disturbed surface conditions, contaminant flux from the perched water occurs over a time interval of tens of years. However, if the recharge rate is 0.35 cm/yr, representative of returning recharge to pre-Hanford Site levels, the contaminant flux into the groundwater is spread over hundreds of years. It was also demonstrated that removal of perched water by pumping would reduce the flux of water (and associated contaminants) to the groundwater, thereby impacting the long-term rate of contaminant movement to the groundwater.

Oostrom, Martinus; Truex, Michael J.; Carroll, KC; Chronister, Glen B.

2013-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Wave-current Interaction and Its Impact on Contaminant Transport Primary Investigator: Meng Xia  

E-Print Network [OSTI]

Wave-current Interaction and Its Impact on Contaminant Transport Primary Investigator: Meng Xia Co Overview This project is designed to develop a three-dimensional coupled Wave-current model that can simulate and predict wave effects on the structure of currents, water level fluctuations, sediments

242

Contaminant desorption during long-term leaching of hydroxide-weathered Hanford sediments  

SciTech Connect (OSTI)

Considerable efforts have been made toward understanding the behavior of contaminants introduced into sediments surrounding high-level radioactive waste (HLRW) storage sites at several Department of Energy (DOE) facilities (Hanford Site, WA; Savannah River Site, SC; Oak Ridge Site, TN).

Thompson, A.; Steefel, C.I.; Perdrial, N.; Chorover, J.

2009-11-01T23:59:59.000Z

243

EULERIANLAGRANGIAN LOCALIZED ADJOINT METHODS FOR TRANS PORT OF NUCLEARWASTE CONTAMINATION IN POROUS MEDIA  

E-Print Network [OSTI]

EULERIAN­LAGRANGIAN LOCALIZED ADJOINT METHODS FOR TRANS­ PORT OF NUCLEAR­WASTE CONTAMINATION­ creasingly threatened by organic, inorganic, and radioactive pollutants as well as high­level nuclear waste developed for use by the Nuclear Regulatory Commission to analyze deep geologic nuclear waste disposal

Ewing, Richard E.

244

D.M. Whitacre (ed) Reviews of Environmental Contamination and Toxicology 214, 87-124  

E-Print Network [OSTI]

in such reinforcement is to evaluate toxic effects at the community level by applying community ecology conceptsD.M. Whitacre (ed) Reviews of Environmental Contamination and Toxicology 214, 87-124 DOI 10.1007/978-1-4614-0668-6_5, © Springer Science+Business Media, LLC 2011 Effects of Organic Herbicides on Phototrophic Microbial

Paris-Sud XI, Université de

245

Removing Radium-226 Contamination From Ion Exchange Resins Used in Drinking Water Treatment  

E-Print Network [OSTI]

Removing Radium-226 Contamination From Ion Exchange Resins Used in Drinking Water Treatment P r o b of groundwater containing high levels of radium-226 activity (Objective 1) were regenerated with prescribed brine that the concentration of salt in the brine cleaning solution was the most influential factor in the resin regeneration

246

Page 1 of 3 Cross-Sectional Exposure Assessment of Environmental Contaminants  

E-Print Network [OSTI]

percentile levels from the Second National Report on Human Exposure to Environmental Chemicals (NationalPage 1 of 3 Cross-Sectional Exposure Assessment of Environmental Contaminants in Churchill County, Nevada -Final Report- February 6, 2003 Centers for Disease Control and Prevention National Center

247

Reduction in maximum time uncertainty of paired time signals  

DOE Patents [OSTI]

Reduction in the maximum time uncertainty (t/sub max/ - t/sub min/) of a series of paired time signals t/sub 1/ and t/sub 2/ varying between two input terminals and representative of a series of single events where t/sub 1/ less than or equal to t/sub 2/ and t/sub 1/ + t/sub 2/ equals a constant, is carried out with a circuit utilizing a combination of OR and AND gates as signal selecting means and one or more time delays to increase the minimum value (t/sub min/) of the first signal t/sub 1/ closer to t/sub max/ and thereby reduce the difference. The circuit may utilize a plurality of stages to reduce the uncertainty by factors of 20 to 800.

Theodosiou, G.E.; Dawson, J.W.

1981-02-11T23:59:59.000Z

248

Probable maximum flood control; Yucca Mountain Site Characterization Project  

SciTech Connect (OSTI)

This study proposes preliminary design concepts to protect the waste-handling facilities and all shaft and ramp entries to the underground from the probable maximum flood (PMF) in the current design configuration for the proposed Nevada Nuclear Waste Storage Investigation (NNWSI) repository protection provisions were furnished by the United States Bureau of Reclamation (USSR) or developed from USSR data. Proposed flood protection provisions include site grading, drainage channels, and diversion dikes. Figures are provided to show these proposed flood protection provisions at each area investigated. These areas are the central surface facilities (including the waste-handling building and waste treatment building), tuff ramp portal, waste ramp portal, men-and-materials shaft, emplacement exhaust shaft, and exploratory shafts facility.

DeGabriele, C.E.; Wu, C.L. [Bechtel National, Inc., San Francisco, CA (United States)

1991-11-01T23:59:59.000Z

249

Fracture Toughness and Maximum Stress in a Disordered Lattice System  

E-Print Network [OSTI]

Fracture in a disordered lattice system is studied. In our system, particles are initially arranged on the triangular lattice and each nearest-neighbor pair is connected with a randomly chosen soft or hard Hookean spring. Every spring has the common threshold of stress at which it is cut. We make an initial crack and expand the system perpendicularly to the crack. We find that the maximum stress in the stress-strain curve is larger than those in the systems with soft or hard springs only (uniform systems). Energy required to advance fracture is also larger in some disordered systems, which indicates that the fracture toughness improves. The increase of the energy is caused by the following two factors. One is that the soft spring is able to hold larger energy than the hard one. The other is that the number of cut springs increases as the fracture surface becomes tortuous in disordered systems.

Chiyori Urabe; Shinji Takesue

2008-12-29T23:59:59.000Z

250

Maximum Margin Clustering for State Decomposition of Metastable Systems  

E-Print Network [OSTI]

When studying a metastable dynamical system, a prime concern is how to decompose the phase space into a set of metastable states. Unfortunately, the metastable state decomposition based on simulation or experimental data is still a challenge. The most popular and simplest approach is geometric clustering which is developed based on the classical clustering technique. However, the prerequisites of this approach are: (1) data are obtained from simulations or experiments which are in global equilibrium and (2) the coordinate system is appropriately selected. Recently, the kinetic clustering approach based on phase space discretization and transition probability estimation has drawn much attention due to its applicability to more general cases, but the choice of discretization policy is a difficult task. In this paper, a new decomposition method designated as maximum margin metastable clustering is proposed, which converts the problem of metastable state decomposition to a semi-supervised learning problem so that...

Wu, Hao

2015-01-01T23:59:59.000Z

251

Improved Maximum Entropy Analysis with an Extended Search Space  

E-Print Network [OSTI]

The standard implementation of the Maximum Entropy Method (MEM) follows Bryan and deploys a Singular Value Decomposition (SVD) to limit the dimensionality of the underlying solution space apriori. Here we present arguments based on the shape of the SVD basis functions and numerical evidence from a mock data analysis, which show that the correct Bayesian solution is not in general recovered with this approach. As a remedy we propose to extend the search basis systematically, which will eventually recover the full solution space and the correct solution. In order to adequately approach problems where an exponentially damped kernel is used, we provide an open-source implementation, using the C/C++ language that utilizes high precision arithmetic adjustable at run-time. The LBFGS algorithm is included in the code in order to attack problems without the need to resort to a particular search space restriction.

Alexander Rothkopf

2013-01-07T23:59:59.000Z

252

Quantum maximum entropy principle for a system of identical particles  

SciTech Connect (OSTI)

By introducing a functional of the reduced density matrix, we generalize the definition of a quantum entropy which incorporates the indistinguishability principle of a system of identical particles. With the present definition, the principle of quantum maximum entropy permits us to solve the closure problem for a quantum hydrodynamic set of balance equations corresponding to an arbitrary number of moments in the framework of extended thermodynamics. The determination of the reduced Wigner function for equilibrium and nonequilibrium conditions is found to become possible only by assuming that the Lagrange multipliers can be expanded in powers of (Planck constant/2pi){sup 2}. Quantum contributions are expressed in powers of (Planck constant/2pi){sup 2} while classical results are recovered in the limit (Planck constant/2pi)->0.

Trovato, M. [Dipartimento di Matematica, Universita di Catania, Viale A. Doria, 95125 Catania (Italy); Reggiani, L. [Dipartimento di Ingegneria dell' Innovazione and CNISM, Universita del Salento, Via Arnesano s/n, 73100 Lecce (Italy)

2010-02-15T23:59:59.000Z

253

Estimation of contamination volume at Seaway Area A, New York.  

SciTech Connect (OSTI)

The purpose of this analysis was to estimate the volume of soil with a radioactive contaminant activity level above the cleanup Guideline at Seaway Area A, Tonawanda, New York. A site-specific cleanup guideline of 40 pCi/g thorium-230 was derived for Seaway, as well as for the nearby Ashland 1 and Ashland 2 sites. All three are Formerly Utilized Sites Remedial Action Program (FUSRAP) properties. The level was developed to ensure protection of human health and the environment and compliance with applicable or relevant and appropriate requirements. The available data included historical discrete soil samples taken at the surface and at depth and results of a surficial gamma walkover with a sodium iodide (NaI) 2x2 sensor. The balance of this document provides background information about the site and discusses the available data sets, the methodology used, and the results and conclusions from the analysis.

Durham, L.; Johnson, R.

1999-08-04T23:59:59.000Z

254

NOVEL TECHNOLOGIES FOR GASEOUS CONTAMINANTS CONTROL  

SciTech Connect (OSTI)

The overall objective of this project is to develop technologies for cleaning/conditioning the syngas from an integrated gasification combined cycle (IGCC) system to meet the tolerance limits for contaminants such as H{sub 2}S, COS, NH{sub 3}, HCN, HCl, and alkali for fuel cell and chemical production applications. RTI's approach is to develop a modular system that (1) removes reduced sulfur species to sub-ppm levels using a hybrid process consisting of a polymer membrane and a regenerable ZnO-coated monolith or a mixed metal oxide sorbent; (2) removes hydrogen chloride vapors to sub-ppm levels using an inexpensive, high-surface area material; and (3) removes NH{sub 3} with acidic adsorbents. RTI is working with MEDAL, Inc., and North Carolina State University (NCSU) to develop polymer membrane technology for bulk removal of H{sub 2}S from syngas. These membranes are being engineered to remove the acid gas components (H{sub 2}S, CO{sub 2}, NH{sub 3}, and H{sub 2}O) from syngas by focusing on the ''solubility selectivity'' of the novel polymer compositions. The desirable components of the syngas (H{sub 2} and CO) are maintained at high-pressure conditions as a non-permeate stream while the impurities are transported across the membrane to the low pressure side. RTI tested commercially available and novel materials from MEDAL using a high-temperature, high-pressure (HTHP) permeation apparatus. H{sub 2}S/H{sub 2} selectivities >30 were achieved, although there was a strong negative dependence with temperature. MEDAL believes that all the polymer compositions tested so far can be prepared as hollow fiber membrane modules using the existing manufacturing technology. For fuel cell and chemical applications, additional sulfur removal (beyond that achievable with the membranes) is required. To overcome limitations of conventional ZnO pellets, RTI is testing a monolith with a thin coating of high surface area zinc-oxide based materials. Alternatively, a regenerable sorbent developed by DOE/NETL (RVS-1) is being evaluated for this application. A multi-cycle test of 2-in. (5-cm) diameter monolith samples demonstrated that <0.5 ppm sulfur can be achieved. Removal of HCl vapors is being accomplished by low-cost materials that combine the known effectiveness of sodium carbonate as an active matrix used with enhanced surface area supports for greater reactivity and capacity at the required operating temperatures. RTI is working with SRI International on this task. Sorbents prepared using diatomaceous earth and sepiolite, impregnated with sodium carbonate achieved steady-state HCl level <100 ppb (target is 10 ppb). Research is continuing to optimize the impregnation and calcination procedures to provide an optimum pore size distribution and other properties. RTI and SRI International have established the feasibility of a process to selectively chemisorb NH3 from syngas on high surface area molecular sieve adsorbents at high temperatures by conducting a series of temperature-programmed reactions at 225 C (437 F). Significant levels of NH{sub 3} were adsorbed on highly acidic adsorbents; the adsorbed NH{sub 3} was subsequently recovered by heating the adsorbent and the regenerated adsorbent was reused. A comprehensive technical and economic evaluation of this modular gas cleaning process was conducted by Nexant to compare capital and operating cost with existing amine based processes. Nexant estimated a total installed cost of $42 million for the RTI process for a 500 MWe IGCC plant based on its current state of development. By comparison, Nexant estimated the installed cost for an equivalent sized plant based on the Rectisol process (which would achieve the same sulfur removal specification) to be $75 million. Thus the RTI process is economically competitive with a state-of-the-art process for syngas cleanup.

B.S. Turk; T. Merkel; A. Lopez-Ortiz; R.P. Gupta; J.W. Portzer; G.N. Krishnan; B.D. Freeman; G.K. Fleming

2001-09-30T23:59:59.000Z

255

Basic radiological studies contamination control experiments  

SciTech Connect (OSTI)

This report describes the results of experiments relating to contamination control performed in support of the Environmental Restoration Programs Retrieval Project. During the years 1950 to 1970 waste contaminated with plutonium and other transuranic radionuclides was disposed of in shallow land-filled pits and trenches at the Idaho National Engineering Laboratory. Due to potential for migration of radionuclides to an existing aquifer the feasibility of retrieving and repackaging the waste for placement in a final repository is being examined as part of a retrieval project. Contamination control experiments were conducted to determine expected respirable and nonrespirable plutonium contaminated dust fractions and the effectiveness of various dust suppression techniques. Three soil types were tested to determine respirable fractions: Rocky Flats Plant generic soil, Radioactive Waste Management Complex generic soil, and a 1:1 blend of the two soil types. Overall, the average respirable fraction of airborne dust was 5.4% by weight. Three contamination control techniques were studied: soil fixative sprays, misting agents, and dust suppression agents. All of the tested agents proved to be effective in reducing dust in the air. Details of product performance and recommended usage are discussed.

Duce, S.W.; Winberg, M.R.; Freeman, A.L.

1989-09-01T23:59:59.000Z

256

Contaminant trap for gas-insulated apparatus  

DOE Patents [OSTI]

A contaminant trap for a gas-insulated electrical conductor is provided. A resinous dielectric body such as Kel-F wax, grease or other sticky polymeric or oligomeric compound is disposed on the inside wall of the outer housing for the conductor. The resinous body is sufficiently sticky at ambient temperatures to immobilize contaminant particles in the insulating gas on the exposed surfaces thereof. An electric resistance heating element is disposed in the resinous body to selectively raise the temperature of the resinous body to a molten state so that the contaminant particles collected on the surface of the body sink into the body so that the surface of the resinous body is renewed to a particle-less condition and, when cooled, returns to a sticky collecting surface.

Adcock, James L. (Knoxville, TN); Pace, Marshall O. (Knoxville, TN); Christophorou, Loucas G. (Oak Ridge, TN)

1984-01-01T23:59:59.000Z

257

Quantum maximum-entropy principle for closed quantum hydrodynamic transport within a Wigner function formalism  

SciTech Connect (OSTI)

By introducing a quantum entropy functional of the reduced density matrix, the principle of quantum maximum entropy is asserted as fundamental principle of quantum statistical mechanics. Accordingly, we develop a comprehensive theoretical formalism to construct rigorously a closed quantum hydrodynamic transport within a Wigner function approach. The theoretical formalism is formulated in both thermodynamic equilibrium and nonequilibrium conditions, and the quantum contributions are obtained by only assuming that the Lagrange multipliers can be expanded in powers of ({h_bar}/2{pi}){sup 2}. In particular, by using an arbitrary number of moments, we prove that (1) on a macroscopic scale all nonlocal effects, compatible with the uncertainty principle, are imputable to high-order spatial derivatives, both of the numerical density n and of the effective temperature T; (2) the results available from the literature in the framework of both a quantum Boltzmann gas and a degenerate quantum Fermi gas are recovered as a particular case; (3) the statistics for the quantum Fermi and Bose gases at different levels of degeneracy are explicitly incorporated; (4) a set of relevant applications admitting exact analytical equations are explicitly given and discussed; (5) the quantum maximum entropy principle keeps full validity in the classical limit, when ({h_bar}/2{pi}){yields}0.

Trovato, M. [Dipartimento di Matematica, Universita di Catania, Viale A. Doria, I-95125 Catania (Italy); Reggiani, L. [Dipartimento di Ingegneria dell' Innovazione and CNISM, Universita del Salento, Via Arnesano s/n, I-73100 Lecce (Italy)

2011-12-15T23:59:59.000Z

258

Reactive Membrane Barriers for Containment of Subsurface Contamination  

SciTech Connect (OSTI)

The overall goal of this project was to develop reactive membrane barriers--a new and flexible technique to contain and stabilize subsurface contaminants. Polymer membranes will leak once a contaminant is able to diffuse through the membrane. By incorporating a reactive material in the polymer, however, the contaminant is degraded or immobilized within the membrane. These processes increase the time for contaminants to breakthrough the barrier (i.e. the lag time) and can dramatically extend barrier lifetimes. In this work, reactive barrier membranes containing zero-valent iron (Fe{sup 0}) or crystalline silicotitanate (CST) were developed to prevent the migration of chlorinated solvents and cesium-137, respectively. These studies were complemented by the development of models quantifying the leakage/kill time of reactive membranes and describing the behavior of products produced via the reactions within the membranes. First, poly(vinyl alcohol) (PVA) membranes containing Fe{sup 0} and CST were prepared and tested. Although PVA is not useful in practical applications, it allows experiments to be performed rapidly and the results to be compared to theory. For copper ions (Cu{sup 2+}) and carbon tetrachloride, the barrier was effective, increasing the time to breakthrough over 300 times. Even better performance was expected, and the percentage of the iron used in the reaction with the contaminants was determined. For cesium, the CST laden membranes increased lag times more than 30 times, and performed better than theoretical predictions. A modified theory was developed for ion exchangers in reactive membranes to explain this result. With the PVA membranes, the effect of a groundwater matrix on barrier performance was tested. Using Hanford groundwater, the performance of Fe{sup 0} barriers decreased compared to solutions containing a pH buffer and high levels of chloride (both of which promote iron reactivity). For the CST bearing membrane, performance improved by a factor of three when groundwater was used in place of deionized water. The performance of high density polyethylene (HDPE) membranes containing Fe{sup 0} was then evaluating using carbon tetrachloride as the target contaminant. Only with a hydrophilic additive (glycerol), was the iron able to extend lag times. Lag times were increased by a factor of 15, but only 2-3% of the iron was used, likely due to formation of oxide precipitates on the iron surface, which slowed the reaction. With thicker membranes and lower carbon tetrachloride concentrations, it is expected that performance will improve. Previous models for reactive membranes were also extended. The lag time is a measurement of when the barrier is breached, but contaminants do slowly leak through prior to the lag time. Thus, two parameters, the leakage and the kill time, were developed to determine when a certain amount of pollutant has escaped (the kill time) or when a given exposure (concentration x time) occurs (the leakage). Finally, a model was developed to explain the behavior of mobile reaction products in reactive barrier membranes. Although the goal of the technology is to avoid such products, it is important to be able to predict how these products will behave. Interestingly, calculations show that for any mobile reaction products, one half of the mass will diffuse into the containment area and one half will escape, assuming that the volumes of the containment area and the surrounding environment are much larger than the barrier membrane. These parameters/models will aid in the effective design of barrier membranes.

William A. Arnold; Edward L. Cussler

2007-02-26T23:59:59.000Z

259

Programmatic methods for addressing contaminated volume uncertainties  

SciTech Connect (OSTI)

Accurate estimates of the volumes of contaminated soils or sediments are critical to effective program planning and to successfully designing and implementing remedial actions. Unfortunately, data available to support the pre-remedial design are often sparse and insufficient for accurately estimating contaminated soil volumes, resulting in significant uncertainty associated with these volume estimates. The uncertainty in the soil volume estimates significantly contributes to the uncertainty in the overall project cost estimates, especially since excavation and off-site disposal are the primary cost items in soil remedial action projects. The U.S. Army Corps of Engineers Buffalo District's experience has been that historical contaminated soil volume estimates developed under the Formerly Utilized Sites Remedial Action Program (FUSRAP) often underestimated the actual volume of subsurface contaminated soils requiring excavation during the course of a remedial activity. In response, the Buffalo District has adopted a variety of programmatic methods for addressing contaminated volume uncertainties. These include developing final status survey protocols prior to remedial design, explicitly estimating the uncertainty associated with volume estimates, investing in pre-design data collection to reduce volume uncertainties, and incorporating dynamic work strategies and real-time analytics in pre-design characterization and remediation activities. This paper describes some of these experiences in greater detail, drawing from the knowledge gained at Ashland 1, Ashland 2, Linde, and Rattlesnake Creek. In the case of Rattlesnake Creek, these approaches provided the Buffalo District with an accurate pre-design contaminated volume estimate and resulted in one of the first successful FUSRAP fixed-price remediation contracts for the Buffalo District. (authors)

Rieman, C.R.; Spector, H.L. [U.S. Army Corps of Engineers Buffalo District, Buffalo, NY (United States); Durham, L.A.; Johnson, R.L. [Argonne National Laboratory, Environmental Science Div., IL (United States)

2007-07-01T23:59:59.000Z

260

How to deal with radiologically contaminated vegetation  

SciTech Connect (OSTI)

This report describes the findings from a literature review conducted as part of a Department of Energy, Office of Technology Development Biomass Remediation Task. The principal objective of this project is to develop a process or group of processes to treat radiologically contaminated vegetation in a manner that minimizes handling, processing, and treatment costs. Contaminated, woody vegetation growing on waste sites at SRS poses a problem to waste site closure technologies that are being considered for these sites. It is feared that large sections of woody vegetation (logs) can not be buried in waste sites where isolation of waste is accomplished by capping the site. Logs or large piles of woody debris have the potential of decaying and leaving voids under the cap. This could lead to cap failure and entrance of water into the waste. Large solid objects could also interfere with treatments like in situ mixing of soil with grout or other materials to encapsulate the contaminated sediments and soils in the waste sites. Optimal disposal of the wood includes considerations of volume reduction, treatment of the radioactive residue resulting from volume reduction, or confinement without volume reduction. Volume reduction consists primarily of removing the carbon, oxygen, and hydrogen in the wood, leaving an ash that would contain most of the contamination. The only contaminant that would be released by volume reduction would by small amounts of the radioactive isotope of hydrogen, tritium. The following sections will describe the waste sites at SRS which contain contaminated vegetation and are potential candidates for the technology developed under this proposal. The description will provide a context for the magnitude of the problem and the logistics of the alternative solutions that are evaluated later in the review. 76 refs.

Wilde, E.W.; Murphy, C.E.; Lamar, R.T.; Larson, M.J.

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Modeling to Support Groundwater Contaminant Boundaries for the Shoal Underground Nuclear Test  

SciTech Connect (OSTI)

Groundwater flow and radionuclide transport at the Shoal underground nuclear test are characterized using three-dimensional numerical models, based on site-specific hydrologic data. The objective of this modeling is to provide the flow and transport models needed to develop a contaminant boundary defining the extent of radionuclide-contaminated groundwater at the site throughout 1,000 years at a prescribed level of confidence. This boundary will then be used to manage the Project Shoal Area for the protection of the public and the environment.

K. Pohlmann; G. Pohll; J. Chapman; A. Hassan; R. Carroll; C. Shirley

2004-03-01T23:59:59.000Z

262

INEEL Subregional Conceptual Model Report; Volume 1 - Summary of Existing Knowledge of Natural and Anthropogenic Influences Governing Subsurface Contaminant Transport in the INEEL Subregion of the Eastern Snake River Plain  

SciTech Connect (OSTI)

The National Research Council has defined a conceptual model as ''an evolving hypothesis identifying the important features, processes, and events controlling fluid flow and contaminant transport of consequence at a specific field site in the context of a recognized problem''. Presently, several subregional conceptual models are under development at the Idaho National Engineering and Environmental Laboratory (INEEL). Additionally, facility-specific conceptual models have been described as part of INEEL environmental restoration activities. Compilation of these models is required to develop a comprehensive conceptual model that can be used to strategically plan for future groundwater research activities at the INEEL. Conceptual models of groundwater flow and contaminant transport at the INEEL include the description of the geologic framework, matrix hydraulic properties, and inflows and outflows. They also include definitions of the contaminant source term and contaminant transport mechanisms. The geologic framework of the INEEL subregion is described by the geometry of the system, stratigraphic units within the system, and structural features that affect groundwater flow and contaminant transport. These elements define geohydrologic units that make up the Snake River Plain Aquifer (SRPA). The United States Geological Survey (USGS) conceptual model encompasses approximately 1,920 mi2 of the eastern Snake River Plain. The Waste Area Group (WAG)-10 model includes the USGS area and additional areas to the northeast and southeast. Both conceptual models are bounded to the northwest by the Pioneer Mountains, Lost River Range, and Lemhi Mountains. They are bounded to the southeast by groundwater flow paths determined from aquifer water-level contours. The upgradient extent of the USGS model is a water-level contour that includes the northeastern boundary of the INEEL. The WAG-10 model includes more of the Mud Lake area to utilize previous estimates of underflow into the subregion. Both conceptual models extend approximately 25 miles to the southwest of the INEEL, a distance sufficient to include known concentrations of contaminant tracers. Several hypotheses have been developed concerning the effective thickness of the SRPA at the INEEL. The USGS model has defined the effective thickness from electrical resistivity and borehole data to be as much as 2,500 ft in the eastern part of the subregion and as much as 4,000 ft in the southwestern part. The WAG-10 model has developed two alternatives using aquifer-temperature and electrical resistivity data. The ''thick'' aquifer interpretation utilizes colder temperature data and includes a northtrending zone in which the thickness exceeds 1,300 ft and with a maximum thickness of 1,700 ft. The ''thin'' aquifer interpretation minimizes aquifer thickness, with thickness ranging from 328 to 1,300 ft. Facility-specific models generally have focused efforts on the upper 250 ft of saturation. Conceptual models have utilized a stratigraphic data set to define geohydrologic units within the INEEL subregion. This data set, compiled from geophysical logs and cores from boreholes, correlates the thick, complex stack of basalt flows across the subregion. Conceptual models generally concur that the upper geohydrologic unit consists of a section of highly fractured, multiple, thin basalt flows and sedimentary interbeds. Beneath this unit is an areally extensive, thick, unfractured basalt flow that rises above the water table southwest of the INEEL. The bottom unit consists of a thick section of slightly- to moderately-altered basalt. A key objective of the DOE water-integration project at the INEEL is to coordinate development of a subregional conceptual model of groundwater flow and contaminant transport that is based on the best available understanding of geologic and hydrologic features. The first step in this process is to compile and summarize the current conceptual models of groundwater flow and contaminant transport at the INEEL that have been developed from extensive geohydrologic studies con

Wichlacz, Paul Louis; Orr, Brennan

2002-08-01T23:59:59.000Z

263

System for removing contaminants from plastic resin  

DOE Patents [OSTI]

A resin recycling system that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The system includes receiving the resin in container form. A grinder grinds the containers into resin particles. The particles are exposed to a solvent in one or more solvent wash vessels, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. A separator is used to separate the resin particles and the solvent. The resin particles are then placed in solvent removing element where they are exposed to a solvent removing agent which removes any residual solvent remaining on the resin particles after separation.

Bohnert, George W. (Harrisonville, MO); Hand, Thomas E. (Lee's Summit, MO); DeLaurentiis, Gary M. (Jamestown, CA)

2010-11-23T23:59:59.000Z

264

E-Print Network 3.0 - atmospheric pollutants levels Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dispersion a. Maximum ground-level ambient concentration b... Pollution Prevention, Control and Sustainability Instructor: V.M. Fthenakis, Tel: (212) 854-8885, Email: vmf......

265

Fundamental Studies of the Removal of Contaminants from Ground and Waste Waters via Reduction by Zero-Valent Metals  

SciTech Connect (OSTI)

Contaminated groundwater and surface waters are a problem throughout the United States and the world. In many instances, the types of contamination can be directly attributed to man's actions. For instance, the burial of chemical wastes, casual disposal of solvents in unlined pits, and the development of irrigated agriculture have all contributed to groundwater and surface water contamination. The kinds of contaminants include chlorinated solvents and toxic trace elements (including radioisotopes) that are soluble and mobile in soils and aquifers. Oxyanions of uranium, selenium, chromium, arsenic, technetium, and chlorine (as perchlorate) are frequently found as contaminants on many DOE sites. Uranium is a particularly widespread contaminant at most DOE sites including Oak Ridge, Rocky Flats, Hanford, Idaho (INEEL), and Fernald. The uranium contamination is associated with mining and milling of uranium ore (UMTRA sites), isotope separation and enrichment, and mixed waste and TRU waste burial. In addition, the careless disposal of halogenated solvents, such as carbon tetrachloride and trichloroethylene, has further contaminated many groundwaters at these sites. A potential remediation method for many of these oxyanions and chlorinated-solvents is to react the contaminated water with zero-valent iron. In this reaction, the iron serves as both an electron source and as a catalyst. Elemental iron is already being used on an experimental basis at many DOE sites. Both in situ reactive barriers and above-ground reactors are being developed for this purpose. However, the design and operation of these treatment systems requires a detailed process-level understanding of the interactions between the contaminants and the iron surfaces. We are performing fundamental investigations of the interactions of the relevant chlorinated solvents and trace element-containing compounds with single- and poly-crystalline Fe surfaces. The aim of this work is to develop th e fundamental physical and chemical understanding that is necessary for the development of cleanup techniques and procedures.

Yarmoff, Jory A.; Amrhein, Christopher

1999-06-01T23:59:59.000Z

266

Spectral Analysis of Excited Nucleons in Lattice QCD with Maximum Entropy Method  

E-Print Network [OSTI]

We study the mass spectra of excited baryons with the use of the lattice QCD simulations. We focus our attention on the problem of the level ordering between the positive-parity excited state N'(1440) (the Roper resonance) and the negative-parity excited state N^*(1535). Nearly perfect parity projection is accomplished by combining the quark propagators with periodic and anti-periodic boundary conditions in the temporal direction. Then we extract the spectral functions from the lattice data by utilizing the maximum entropy method. We observe that the masses of the N' and N^* states are close for wide range of the quark masses (M_pi=0.61-1.22 GeV), which is in contrast to the phenomenological prediction of the quark models. The role of the Wilson doublers in the baryonic spectral functions is also studied.

Kiyoshi Sasaki; Shoichi Sasaki; Tetsuo Hatsuda

2005-07-12T23:59:59.000Z

267

Treatment of Mercury Contaminated Oil from the Mound Site  

SciTech Connect (OSTI)

Over one thousand gallons of tritiated oil, at various contamination levels, are stored in the Main Hill Tritium Facility at the Miamisburg Environmental Management Project (MEMP), commonly referred to as Mound Site. This tritiated oil is to be characterized for hazardous materials and radioactive contamination. Most of the hazardous materials are expected to be in the form of heavy metals, i.e., mercury, silver, lead, chromium, etc, but transuranic materials and PCBs could also be in some oils. Waste oils, found to contain heavy metals as well as being radioactively contaminated, are considered as mixed wastes and are controlled by Resource Conservation and Recovery Act (RCRA) regulations. The SAMMS (Self-Assembled Mercaptan on Mesoporous Silica) technology was developed by the Pacific Northwest National Laboratory (PNNL) for removal and stabilization of RCRA metals (i.e., lead, mercury, cadmium, silver, etc.) and for removal of mercury from organic solvents. The SAMMS material is based on self-assembly of functionalized monolayers on mesoporous oxide surfaces. The unique mesoporous oxide supports provide a high surface area, thereby enhancing the metal-loading capacity. SAMMS material has high flexibility in that it binds with different forms of mercury, including metallic, inorganic, organic, charged, and neutral compounds. The material removes mercury from both organic wastes, such as pump oils, and from aqueous wastes. Mercury-loaded SAMMS not only passes TCLP tests, but also has good long-term durability as a waste form because: (1) the covalent binding between mercury and SAMMS has good resistance in ion-exchange, oxidation, and hydrolysis over a wide pH range and (2) the uniform and small pore size of the mesoporous silica prevents bacteria from solubilizing the bound mercury.

Klasson, KT

2000-11-09T23:59:59.000Z

268

Savannah River Site radioiodine atmospheric releases and offsite maximum doses  

SciTech Connect (OSTI)

Radioisotopes of iodine have been released to the atmosphere from the Savannah River Site since 1955. The releases, mostly from the 200-F and 200-H Chemical Separations areas, consist of the isotopes, I-129 and 1-131. Small amounts of 1-131 and 1-133 have also been released from reactor facilities and the Savannah River Laboratory. This reference memorandum was issued to summarize our current knowledge of releases of radioiodines and resultant maximum offsite doses. This memorandum supplements the reference memorandum by providing more detailed supporting technical information. Doses reported in this memorandum from consumption of the milk containing the highest I-131 concentration following the 1961 1-131 release incident are about 1% higher than reported in the reference memorandum. This is the result of using unrounded 1-131 concentrations of I-131 in milk in this memo. It is emphasized here that this technical report does not constitute a dose reconstruction in the same sense as the dose reconstruction effort currently underway at Hanford. This report uses existing published data for radioiodine releases and existing transport and dosimetry models.

Marter, W.L.

1990-11-01T23:59:59.000Z

269

Maximum Entropy Analysis of the Spectral Functions in Lattice QCD  

E-Print Network [OSTI]

First principle calculation of the QCD spectral functions (SPFs) based on the lattice QCD simulations is reviewed. Special emphasis is placed on the Bayesian inference theory and the Maximum Entropy Method (MEM), which is a useful tool to extract SPFs from the imaginary-time correlation functions numerically obtained by the Monte Carlo method. Three important aspects of MEM are (i) it does not require a priori assumptions or parametrizations of SPFs, (ii) for given data, a unique solution is obtained if it exists, and (iii) the statistical significance of the solution can be quantitatively analyzed. The ability of MEM is explicitly demonstrated by using mock data as well as lattice QCD data. When applied to lattice data, MEM correctly reproduces the low-energy resonances and shows the existence of high-energy continuum in hadronic correlation functions. This opens up various possibilities for studying hadronic properties in QCD beyond the conventional way of analyzing the lattice data. Future problems to be studied by MEM in lattice QCD are also summarized.

M. Asakawa; T. Hatsuda; Y. Nakahara

2001-02-26T23:59:59.000Z

270

Improved Maximum Entropy Method with an Extended Search Space  

E-Print Network [OSTI]

We report on an improvement to the implementation of the Maximum Entropy Method (MEM). It amounts to departing from the search space obtained through a singular value decomposition (SVD) of the Kernel. Based on the shape of the SVD basis functions we argue that the MEM spectrum for given $N_\\tau$ data-points $D(\\tau)$ and prior information $m(\\omega)$ does not in general lie in this $N_\\tau$ dimensional singular subspace. Systematically extending the search basis will eventually recover the full search space and the correct extremum. We illustrate this idea through a mock data analysis inspired by actual lattice spectra, to show where our improvement becomes essential for the success of the MEM. To remedy the shortcomings of Bryan's SVD prescription we propose to use the real Fourier basis, which consists of trigonometric functions. Not only does our approach lead to more stable numerical behavior, as the SVD is not required for the determination of the basis functions, but also the resolution of the MEM becomes independent from the position of the reconstructed peaks.

Alexander Rothkopf

2012-08-25T23:59:59.000Z

271

Maximum entropy detection of planets around active stars  

E-Print Network [OSTI]

(shortened for arXiv) We aim to progress towards more efficient exoplanet detection around active stars by optimizing the use of Doppler Imaging in radial velocity measurements. We propose a simple method to simultaneously extract a brightness map and a set of orbital parameters through a tomographic inversion technique derived from classical Doppler mapping. Based on the maximum entropy principle, the underlying idea is to determine the set of orbital parameters that minimizes the information content of the resulting Doppler map. We carry out a set of numerical simulations to perform a preliminary assessment of the robustness of our method, using an actual Doppler map of the very active star HR 1099 to produce a realistic synthetic data set for various sets of orbital parameters of a single planet in a circular orbit. Using a simulated time-series of 50 line profiles affected by a peak-to-peak activity jitter of 2.5 km/s, we are able in most cases to recover the radial velocity amplitude, orbital phase and o...

Petit, P; Hébrard, E; Morin, J; Folsom, C P; Böhm, T; Boisse, I; Borgniet, S; Bouvier, J; Delfosse, X; Hussain, G; Jeffers, S V; Marsden, S C; Barnes, J R

2015-01-01T23:59:59.000Z

272

Bioremediation of ground water contaminants at a uranium mill tailings site  

SciTech Connect (OSTI)

Ground water contaminated with uranium from milling operations must be remediated to reduce the migration of soluble toxic compounds. At the mill tailings site near Tuba City, Arizona (USA) the approach is to employ bioremediation for in situ immobilization of uranium by bacterial reduction of uranyl, U(VI), compounds to uraninite, U(IV). In this initial phase of remediation, details are provided to indicate the magnitude of the contamination problem and to present preliminary evidence supporting the proposition that bacterial immobilization of uranium is possible. Additionally, consideration is given to contaminating cations and anions that may be at toxic levels in ground water at this uranium mill tailing site and detoxification strategies using bacteria are addressed. A model concept is employed so that results obtained at the Tuba City site could contribute to bioremediation of ground water at other uranium mill tailings sites.

Barton, L.L.; Nuttall, H.E.; Thomson, B.M.; Lutze, W. [Univ. of New Mexico, Albuquerque, NM (United States)

1995-12-31T23:59:59.000Z

273

Physical properties of soils contaminated by oil lakes, Kuwait  

SciTech Connect (OSTI)

In preparation for a marine assault by the coalition forces, the Iraqi Army heavily mined Kuwait`s coastal zone and the oil fields. Over a million mines were placed on the Kuwait soil. Burning of 732 oil wells in the State of Kuwait due to the Iraqi invasion caused damages which had direct and indirect effect on environment. A total of 20-22 million barrels of spilled crude oil were collected in natural desert depressions and drainage network which formed more than 300 oil lakes. The total area covered with oil reached 49 km{sup 2}. More than 375 trenches revealed the existence of hard, massive caliche (CaCO{sub 3}) subsoil which prevent leached oil from reaching deeper horizons, and limited the maximum depth of penetration to 1.75 m. Total volume of soil contaminated reached 22,652,500 m{sup 3} is still causing environmental problems and needs an urgent cleaning and rehabilitation. Kuwait Oil Company has recovered approximately 21 million barrels from the oil lakes since the liberation of Kuwait. In our examined representative soil profiles the oil penetration was not deeper than 45 cm. Infiltration rate, soil permeability, grain size distribution, aggregates formation and water holding capacity were assessed. 15 refs., 5 figs., 5 tabs.

Mohammad, A.S. [Kuwait Univ., Safat (Kuwait); Wahba, S.A.; Al-Khatieb, S.O. [Arabian Gulf Univ. (Bahrain)

1996-08-01T23:59:59.000Z

274

The Health Risks: Seafood Contamination, Harmful Algal  

E-Print Network [OSTI]

health products from the sea. What is the central issue? Why should I care? How will OHH researchThe Health Risks: Seafood Contamination, Harmful Algal Blooms and Polluted Beaches Seafood associated public health costs. Announcing a New Interagency Report on Oceans and Human Health Research

275

Oxygen and Nitrogen Contamination During Arc Welding  

E-Print Network [OSTI]

) ) : ,- Oxygen and Nitrogen Contamination During Arc Welding T. W. Eagar Department of }faterials, shielded metal arc, self-shielded metal arc, and submerged arc welding are reviewed. Calcu- lations upon heating is also discussed. Introduction Oxygen and nitrogen ~ontamination of weld metal

Eagar, Thomas W.

276

RESEARCH ARTICLE Assessment of metal contaminations leaching  

E-Print Network [OSTI]

RESEARCH ARTICLE Assessment of metal contaminations leaching out from recycling plastic bottles syntheses, partic- ularly antimony, human exposure to metal release from plastic bottles has been a serious from a series of recycling plastic bottles upon treatments. Methodology In this study, leaching

Short, Daniel

277

Passive treatment of wastewater and contaminated groundwater  

DOE Patents [OSTI]

A bioremediation system using inorganic oxide-reducing microbial consortia for the treatment of, inter alia coal mine and coal yard runoff uses a containment vessel for contaminated water and a second, floating phase for nutrients. Biodegradable oils are preferred nutrients.

Phifer, Mark A. (N. Augusta, SC); Sappington, Frank C. (Dahlonega, GA); Millings, Margaret R. (N. Augusta, SC); Turick, Charles E. (Aiken, SC); McKinsey, Pamela C. (Aiken, SC)

2007-11-06T23:59:59.000Z

278

Passive treatment of wastewater and contaminated groundwater  

DOE Patents [OSTI]

A bioremediation system using inorganic oxide-reducing microbial consortia for the treatment of, inter alia coal mine and coal yard runoff uses a containment vessel for contaminated water and a second, floating phase for nutrients. Biodegradable oils are preferred nutrients.

Phifer, Mark A.; Sappington, Frank C.; Millings, Margaret R.; Turick, Charles E.; McKinsey, Pamela C.

2006-12-12T23:59:59.000Z

279

Persistence of chlorinated hydrocarbon contamination in a California marine ecosystem  

SciTech Connect (OSTI)

Despite major reductions in the dominant DDT and polychlorinated biphenyls (PCB) input off Los Angeles (California, U.S.A.) in the early 1970s, the levels of these pollutants decreased only slightly from 1972 to 1975 both in surficial bottom sediments and in a flatfish bioindicator (Dover sole, Microstomus pacificus) collected near the submarine outfall. Concentrations of these pollutants in the soft tissues of the mussel Mytilus californianus, collected intertidally well inshore of the highly contaminated bottom sediments, followed much more closely the decreases in the outfall discharges. These observations suggest that contaminated sediments on the seafloor were the principal (although not necessarily direct) cause of the relatively high and persistent concentrations of DDT and PCB residues in tissues. The study indicated that residues of the higher-molecular-weight chlorinated hydrocarbons, such as DDT and PCB, can be highly persistent once released to coastal marine ecosystems and that their accumulation in surficial bottom sediments is the most likely cause of this persistence observed in the biota of the discharge zone.

Young, D.R.; Gossett, R.W.; Heesen, T.C.

1989-01-01T23:59:59.000Z

280

Elevated sulfate reduction in metal-contaminated freshwater lake sediments  

SciTech Connect (OSTI)

Although sulfate-reducing prokaryotes have long been studied as agents of metals bioremediation, impacts of long-term metals exposure on biologically mediated sulfur cycling in natural systems remains poorly understood. The effects of long-term exposure to metal stress on the freshwater sulfur cycle were studied, with a focus on biologic sulfate reduction using a combination of microbial and chemical methods. To examine the effects after decades of adaptation time, a field-based experiment was conducted using multiple study sites in a natural system historically impacted by a nearby zinc smelter (Lake DePue, Illinois). Rates were highest at the most metals-contaminated sites (-35 {mu}mol/cm{sup 3}/day) and decreased with decreased pore water zinc and arsenic contamination levels, while other environmental characteristics (i.e., pH, nutrient concentrations and physical properties) showed little between-site variation. Correlations were established using an artificial neural network to evaluate potentially non-linear relationships between sulfate reduction rates (SRR) and measured environmental variables. SRR in Lake DePue were up to 50 times higher than rates previously reported for lake sediments and the chemical speciation of Zn was dominated by the presence of ZnS as shown by X-ray Absorption Spectroscopy (XAS). These results suggest that long-term metal stress of natural systems might alter the biogeochemical cycling of sulfur by contributing to higher rates of sulfate reduction.

Gough, H.L.; Dahl, A.L.; Tribou, E.; Noble, P.A.; Gaillard, J.-F.; Stahl, D.A. (UWASH); (NWU)

2009-01-06T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Using Downhole Probes to Locate and Characterize Buried Transuranic and Mixed Low Level Waste  

SciTech Connect (OSTI)

Borehole logging probes were developed and tested to locate and quantify transuranic elements in subsurface disposal areas and in contaminated sites at USDOE Weapons Complex sites. A new method of measuring very high levels of chlroine in the subsurface was developed using pulsed neutron technology from oilfield applications. The probes were demonstrated at the Hanford site in wells containing plutonium and other contaminants.

Steinman, Donald K; Bramblett, Richard L; Hertzog, Russel C

2012-06-25T23:59:59.000Z

282

Analytical Electron Microscopy examination of uranium contamination at the DOE Fernald operation site  

SciTech Connect (OSTI)

Analytical Electron Microscopy (AEM) has been used to identify uranium-bearing phases present in contaminated soils from the DOE Fernald operation site. A combination of optical microscopy, scanning electron microscopy with backscattered electron detection (SEM/BSE), and AEM was used in isolating and characterizing uranium-rich regions of the contaminated soils. Soil samples were prepared for transmission electron microscopy (TEM) by ultramicrotomy using an embedding resin previously employed for aquatic colloids and biological samples. This preparation method allowed direct comparison between SEM and TEM images. At the macroscopic level much of the uranium appears to be associated with clays in the soils; however, electron beam analysis revealed that the uranium is present as discrete phases, including iron oxides, silicates (soddyite), phosphates (autunites), and fluorite. Only low levels of uranium were actually within the clay minerals. The distribution of uranium phases was inhomogeneous at the submicron level.

Buck, E.C.; Dietz, N.L.; Bates, J.K.; Cunnane, J.C.

1993-02-01T23:59:59.000Z

283

Water Quality Guide for Livestock and Poultry  

E-Print Network [OSTI]

This publication discusses some of the most common contaminants in the drinking water of livestock and poultry. A table lists the Maximum Contaminant Level of some harmful substances....

Mukhtar, Saqib

1998-09-30T23:59:59.000Z

284

Characterization and inventory of contaminants in WAG 2 floodplain soils of White Oak Creek  

SciTech Connect (OSTI)

A remedial investigation was conducted to determine the extent and type of contamination in the floodplain soils of Waste Area Grouping (WAG) 2, in conjunction with environmental restoration activities at the US Department of Energy (DOE) Oak Ridge Reservation (ORR). WAG 2 is located downstream from the main Oak Ridge National Laboratory (ORNL) plant area. As a result of past, present, and potential future releases of hazardous substances to the environment, the ORR was placed on the National Priorities List in December 1989. Sites on this list must be investigated to determine if remedial actions are possible. This report documents the findings of the remedial investigation of the WAG 2 floodplain soils by (1) presenting the characterization and inventory of contaminants, (2) comparing the walkover survey data to quantitative gamma-emitting radionuclide data, and (3) presenting an assessment of human health risk from exposure to these soils. Contaminant characterization results indicated that the primary contaminants in the WAG 2 floodplain are the gamma-emitting radionuclides {sup 137}Cs and {sup 60}Co, although cobalt activity levels are 1/25th or less than those of cesium. Inorganic contaminants discussed in this report were limited to those contributing significantly to human exposure: antimony, barium, chromium(IV), manganese, mercury, and nickel.

Ford, C.J.; Nyquist, J.E.; Purucker, S.T. [Oak Ridge National Lab., TN (United States); Burgoa, B.B. [CDM Federal Programs Corp., Oak Ridge, TN (United States); Winterfield, R.F. [STEP Environmental, Inc., Oak Ridge, TN (United States)

1997-01-01T23:59:59.000Z

285

Soil washing as a potential remediation technology for contaminated DOE sites  

SciTech Connect (OSTI)

Frequently detected contaminants at US Department of Energy (DOE) sites include radionuclides, heavy metals, and chlorinated hydrocarbons. Remediation of these sites requires application of several technologies used in concert with each other, because no single technology is universally applicable. Special situations, such as mixed waste, generally require innovative technology development. This paper, however, focuses on contaminated soils, for which soil washing and vitrification technologies appear to have wide ranging application potential. Because the volumes of contaminated soils around the DOE complex are so large, soil washing can offer a potentially inexpensive way to effect remediation or to attain waste volume reduction. As costs for disposal of low-level and mixed wastes continue to rise, it is likely that volume-reduction techniques and in-situ containment techniques will become increasingly important. This paper reviews the status of the soil washing technology, examines the systems that are currently available, and discusses the potential application of this technology to some DOE sites, with a focus on radionuclide contamination and, primarily, uranium-contaminated soils

Devgun, J.S.; Beskid, N.J. (Argonne National Lab., IL (United States)); Natsis, M.E. (Princeton Univ., NJ (United States)); Walker, J.S. (USDOE, Washington, DC (United States))

1993-01-01T23:59:59.000Z

286

Soil washing as a potential remediation technology for contaminated DOE sites  

SciTech Connect (OSTI)

Frequently detected contaminants at US Department of Energy (DOE) sites include radionuclides, heavy metals, and chlorinated hydrocarbons. Remediation of these sites requires application of several technologies used in concert with each other, because no single technology is universally applicable. Special situations, such as mixed waste, generally require innovative technology development. This paper, however, focuses on contaminated soils, for which soil washing and vitrification technologies appear to have wide ranging application potential. Because the volumes of contaminated soils around the DOE complex are so large, soil washing can offer a potentially inexpensive way to effect remediation or to attain waste volume reduction. As costs for disposal of low-level and mixed wastes continue to rise, it is likely that volume-reduction techniques and in-situ containment techniques will become increasingly important. This paper reviews the status of the soil washing technology, examines the systems that are currently available, and discusses the potential application of this technology to some DOE sites, with a focus on radionuclide contamination and, primarily, uranium-contaminated soils

Devgun, J.S.; Beskid, N.J. [Argonne National Lab., IL (United States); Natsis, M.E. [Princeton Univ., NJ (United States); Walker, J.S. [USDOE, Washington, DC (United States)

1993-03-01T23:59:59.000Z

287

contaminated The U.S.Army Corps of EngineersCenterfor ContaminatedSediments  

E-Print Network [OSTI]

and OceanWaters 53 Bioassays 53 ContaminantPathway Test '%Dredging Operationsand Enviro '% USACE Risk Assessment Guidance for Con- Research (DOER) Program : &ina6d gebents %Environmental Impact EvaIua USACE

US Army Corps of Engineers

288

Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events  

SciTech Connect (OSTI)

F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events.

Aponte, C.I.

2000-02-17T23:59:59.000Z

289

HOSPITAL VENTILATION STANDARDS AND ENERGY CONSERVATION: CHEMICAL CONTAMINATION OF HOSPITAL AIR. FINAL REPORT.  

E-Print Network [OSTI]

STANDARDS AND ENERGY CONSERVATION: CHH1ICAL CONTAMINATION OFSTANDARDS AND ENERGY CONSERVATION CHEMICAL CONTAMINATION OFSTANDARDS AND ENERGY CONSERVATION: CHEMICAL CONTAMINATION OF

Rainer, David

2012-01-01T23:59:59.000Z

290

Method to remove uranium/vanadium contamination from groundwater  

DOE Patents [OSTI]

A process for removing uranium/vanadium-based contaminants from groundwater using a primary in-ground treatment media and a pretreatment media that chemically adjusts the groundwater contaminant to provide for optimum treatment by the primary treatment media.

Metzler, Donald R. (DeBeque, CO); Morrison, Stanley (Grand Junction, CO)

2004-07-27T23:59:59.000Z

291

Microsoft Word - NGNP_Contamination Control Report-050108 FINAL...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

94 NGNP-NHS 50-CC Contamination Control 8 of 101 NGNP-Contamination Control Report-050108.doc 2008 Westinghouse Electric Company LLC LIST OF FIGURES Figure 1-1...

292

Method to Remove Uranium/Vanadium Contamination from Groundwater  

DOE Patents [OSTI]

A process for removing uranium/vanadium-based contaminants from groundwater using a primary in-ground treatment media and a pretreatment media that chemically adjusts the groundwater contaminant to provide for optimum treatment by the primary treatment media.

Metzler, Donald R.; Morrison Stanley

2004-07-27T23:59:59.000Z

293

Study of Different Implementation Approaches for a Maximum Power Point Florent Boico Brad Lehman  

E-Print Network [OSTI]

will study the design of a maximum power point tracker for low power solar panels (10-50W). In the process weStudy of Different Implementation Approaches for a Maximum Power Point Tracker 1 Florent Boico Brad Lehman Northeastern University Abstract: This paper studies the design of a Maximum Power Point Tracker

Lehman, Brad

294

A Maximum Entropy Algorithm for Rhythmic Analysis of Genome-Wide Expression Patterns  

E-Print Network [OSTI]

A Maximum Entropy Algorithm for Rhythmic Analysis of Genome-Wide Expression Patterns Christopher James Langmead C. Robertson McClung Bruce Randall Donald ,,,§,¶ Abstract We introduce a maximum entropy-based spectral analysis, maximum entropy spectral reconstruction is well suited to signals of the type generated

Richardson, David

295

1 A MAXIMUM ENTROPY METHOD FOR SUBNETWORK ORIGIN-DESTINATION 2 TRIP MATRIX ESTIMATION  

E-Print Network [OSTI]

1 A MAXIMUM ENTROPY METHOD FOR SUBNETWORK ORIGIN-DESTINATION 2 TRIP MATRIX ESTIMATION 3 4 Chi Xie 5, maximum entropy, linearization 36 algorithm, column generation 37 #12;C. Xie, K.M. Kockelman and S is the trip matrix of the simplified network. This paper discusses a5 maximum entropy method

Kockelman, Kara M.

296

Maximum entropy and Bayesian approaches to the ratio problem Edward Z. Shen*  

E-Print Network [OSTI]

Maximum entropy and Bayesian approaches to the ratio problem Edward Z. Shen* Jeffrey M. Perloff** January 2001 Abstract Maximum entropy and Bayesian approaches provide superior estimates of a ratio extra information in the supports for the underlying parameters for generalized maximum entropy (GME

Perloff, Jeffrey M.

297

Comparison of Maximum Entropy and Higher-Order Entropy Estimators Amos Golan* and Jeffrey M. Perloff**  

E-Print Network [OSTI]

Comparison of Maximum Entropy and Higher-Order Entropy Estimators Amos Golan* and Jeffrey M. Perloff** ABSTRACT We show that the generalized maximum entropy (GME) is the only estimation method- classes of estimators may outperform the GME estimation rule. Keywords: generalized entropy, maximum

Perloff, Jeffrey M.

298

A maximum entropy-least squares estimator for elastic origin-destination trip matrix estimation  

E-Print Network [OSTI]

A maximum entropy-least squares estimator for elastic origin- destination trip matrix estimation propose a combined maximum entropy-least squares (ME-LS) estimator, by which O- D flows are distributed-destination trip table; elastic demand; maximum entropy; least squares; subnetwork analysis; convex combination

Kockelman, Kara M.

299

Final Project Report: Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport  

SciTech Connect (OSTI)

Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided detailed characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, PCO2, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions.

Jon Chorover, University of Arizona; Peggy O' €  ™ Day, University of California, Merced; Karl Mueller, Penn State University; Wooyong Um, Pacific Northwest National Laboratory; Carl Steefel, Lawrence Berkeley National Laboratory

2012-10-01T23:59:59.000Z

300

THE MAXIMUM ENERGY OF ACCELERATED PARTICLES IN RELATIVISTIC COLLISIONLESS SHOCKS  

SciTech Connect (OSTI)

The afterglow emission from gamma-ray bursts (GRBs) is usually interpreted as synchrotron radiation from electrons accelerated at the GRB external shock that propagates with relativistic velocities into the magnetized interstellar medium. By means of multi-dimensional particle-in-cell simulations, we investigate the acceleration performance of weakly magnetized relativistic shocks, in the magnetization range 0 {approx}< {sigma} {approx}< 10{sup -1}. The pre-shock magnetic field is orthogonal to the flow, as generically expected for relativistic shocks. We find that relativistic perpendicular shocks propagating in electron-positron plasmas are efficient particle accelerators if the magnetization is {sigma} {approx}< 10{sup -3}. For electron-ion plasmas, the transition to efficient acceleration occurs for {sigma} {approx}< 3 Multiplication-Sign 10{sup -5}. Here, the acceleration process proceeds similarly for the two species, since the electrons enter the shock nearly in equipartition with the ions, as a result of strong pre-heating in the self-generated upstream turbulence. In both electron-positron and electron-ion shocks, we find that the maximum energy of the accelerated particles scales in time as {epsilon}{sub max}{proportional_to}t {sup 1/2}. This scaling is shallower than the so-called (and commonly assumed) Bohm limit {epsilon}{sub max}{proportional_to}t, and it naturally results from the small-scale nature of the Weibel turbulence generated in the shock layer. In magnetized plasmas, the energy of the accelerated particles increases until it reaches a saturation value {epsilon}{sub sat}/{gamma}{sub 0} m{sub i}c {sup 2} {approx} {sigma}{sup -1/4}, where {gamma}{sub 0} m{sub i}c {sup 2} is the mean energy per particle in the upstream bulk flow. Further energization is prevented by the fact that the self-generated turbulence is confined within a finite region of thickness {proportional_to}{sigma}{sup -1/2} around the shock. Our results can provide physically grounded inputs for models of non-thermal emission from a variety of astrophysical sources, with particular relevance to GRB afterglows.

Sironi, Lorenzo [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Spitkovsky, Anatoly [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544-1001 (United States); Arons, Jonathan, E-mail: lsironi@cfa.harvard.edu [Department of Astronomy, Department of Physics, and Theoretical Astrophysics Center, University of California, Berkeley, CA 94720 (United States)

2013-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
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301

Composite Analysis for Low-Level Waste Disposal in the 200 Area Plateau of the Hanford Site, Southeast Washington  

SciTech Connect (OSTI)

A composite analysis of low-level radioactive waste disposal and other radioactive sources was recently completed for the Hanford Site in Southeast Washington State. Impacts from source release and environmental transport were estimated for a 1000-year period following Site closure in a multi-step process involving 1) estimation of radiological inventories and release, 2) assessment of contaminant migration through the vadose zone, groundwater, and atmospheric pathways, 3) and estimation of doses. The analysis showed that most of the radionuclide inventory in past-practice liquid discharge sites and pre-1988 solid waste burial grounds on the 200 Area Plateau will be released in the first several hundred years following Hanford Site closure, well before projected releases from active and planned disposals of solid waste. The maximum predicted agricultural dose was less than 6 mrem/y in 2050 and declined thereafter. The maximum doses for the residential, industrial, and recreational scenarios, were 2.2, 0.7, and 0.04 mrem/y, respectively, and also declined after 2050.

Kincaid, Charles T.; Bergeron, Marcel P.; Cole, Charles R.; Freshley, Mark D.; Johnson, Vernon G.; Kaplan, D. I.; Serne, R. Jeffrey; Streile, Gary P.; Strenge, Dennis L.; Thorne, Paul D.; Vail, Lance W.; Whyatt, Greg A.; Wurstner, Signe K.

2000-03-01T23:59:59.000Z

302

Land treatment of contaminated sludge with wastewater irrigation  

SciTech Connect (OSTI)

A large-scale field experiment was conducted to test the feasibility of land application of sludge from industrial and domestic wastewater treatment to determine the fate and environmental impact of the contaminants. The sludge contained 13 organic priority pollutants, 16 additional environmentally significant organic compounds, and high concentrations of several metals (zinc, copper, lead, nickel, and cadmium). Each compound was monitored as the irrigation water percolated through the soil and the groundwater over time. Most of the organic compounds diminished to non-detectable levels by the end of the study, and the metals proved harmless to the environment. The effectiveness of land application of sludge with wastewater irrigation was clearly demonstrated. 1 figure, 11 tables.

Demirjian, Y.A.; Westman, T.R.; Joshi, A.M.; Rop, D.J.; Buhl, R.V.; Clark, W.R.

1984-04-01T23:59:59.000Z

303

Recommendation 195: Mitigation of Contamination in Bear Creek Burial Grounds  

Broader source: Energy.gov [DOE]

The ORSSAB requests DOE provide possible remedial actions to mitigate releases of contamination from Bear Creek Burial Grounds.

304

Effect of Coal Contaminants on Solid Oxide Fuel System Performance and Service Life  

SciTech Connect (OSTI)

The U.S. Department of Energy’s SECA program envisions the development of high-efficiency, low-emission, CO2 sequestration-ready, and fuel-flexible technology to produce electricity from fossil fuels. One such technology is the integrated gasification-solid oxide fuel cell (SOFC) that produces electricity from the gas stream of a coal gasifier. SOFCs have high fuel-to-electricity conversion efficiency, environmental compatibility (low NOx production), and modularity. The primary objective of the Phase I study was to determine the sensitivity of the performance of solid oxide fuel cells to trace level contaminants present in a coal-derived gas stream in the temperature range 700? to 900?C. Laboratory-scale tests were performed with 1-inch diameter solid oxide fuel cells procured from InDec B.V., Netherlands. These cells produce 0.15, 0.27, and 0.35 W/cm2 at 700?, 750?, and 800?C, respectively, in a H2 anode feed and are expected to be stable within 10% of the original performance over a period of 2000 h. A simulated coal-derived gas containing 30.0% CO, 30.6% H2 11.8% CO2, 27.6% H2O was used at a rate of ~100 standard cm3/min to determine the effect of contaminants on the electrical performance of the cells. Alumina or zirconia components were used for the gas manifold to prevent loss of contaminants by reaction with the surfaces of the gas manifold Short-term accelerated tests were conducted with several contaminants including As, P, CH3Cl, HCl, Hg, Sb, and Zn vapors. In these tests, AsH3, PH3, Cd vapor and CH3Cl identified as the potential contaminants that can affect the electrical performance of SOFCs. The effect of some of these contaminants varied with the operating temperature. Cell failure due to contact break inside the anode chamber occurred when the cell was exposed to 10 ppm arsenic vapor at 800?C. The electrical performance of SOFC samples suffered less than 1% in when exposed to contaminants such as HCl(g), Hg(g), and Zn(g), and SbO(g) at levels of 8 ppm and above. AsH3 vapor at 0.5 ppm did not affect the electrical performance of an SOFC sample even after 1000 h at 750?C. In Phase II of the program, long-term tests will be performed with multiple contaminants at a temperature range of 750? to 850?C. These tests will be at contaminant levels typical of coal-derived gas streams that have undergone gas cleanup using Selexol technology. The chemical nature of the contaminant species will be identified at the operating temperature of SOFC and compare them with thermodynamic equilibrium calculations. The results of the testing will be used to recommend the sensitivity limits for SOFC operation and to assess the reduction in the service life of the SOFC for trace level contaminants.

Gopala N. Krishnan, Palitha Jayaweera, Jordi Perez, M. Hornbostel, John. R. Albritton and Raghubir P. Gupta

2007-10-31T23:59:59.000Z

305

LANDFILL OPERATION FOR CARBON SEQUESTRATION AND MAXIMUM METHANE EMISSION CONTROL  

SciTech Connect (OSTI)

''Conventional'' waste landfills emit methane, a potent greenhouse gas, in quantities such that landfill methane is a major factor in global climate change. Controlled landfilling is a novel approach to manage landfills for rapid completion of total gas generation, maximizing gas capture and minimizing emissions of methane to the atmosphere. With controlled landfilling, methane generation is accelerated and brought to much earlier completion by improving conditions for biological processes (principally moisture levels) in the landfill. Gas recovery efficiency approaches 100% through use of surface membrane cover over porous gas recovery layers operated at slight vacuum. A field demonstration project's results at the Yolo County Central Landfill near Davis, California are, to date, highly encouraging. Two major controlled landfilling benefits would be the reduction of landfill methane emissions to minuscule levels, and the recovery of greater amounts of landfill methane energy in much shorter times than with conventional landfill practice. With the large amount of US landfill methane generated, and greenhouse potency of methane, better landfill methane control can play a substantial role in reduction of US greenhouse gas emissions.

Don Augenstein

1999-01-11T23:59:59.000Z

306

In-Situ Thermal Remediation of Contaminated Soil1  

E-Print Network [OSTI]

as follows. Over a period of several weeks, electrical energy is introduced to the contaminated soil usingChapter 1 In-Situ Thermal Remediation of Contaminated Soil1 Written by Huaxiong Huang,2 Serguei Lapin and Rex Westbrook 1.1 Background Recently, a method for removing contaminants from soil (several

Lapin, Sergey

307

Toxic Contaminants and Their Effects on Resident Fish  

E-Print Network [OSTI]

Science-Policy Exchange September 10, 2009 #12;Take-away themes Toxic contaminants are present are source areas for toxic contaminants for multiple fish stocks A better understanding of the effects and restore fish and ecosystem health #12;Take-away themes Toxic contaminants are present in the Columbia

308

Influences of climate on aflatoxin producing fungi and aflatoxin contamination  

E-Print Network [OSTI]

,b,, Ramon Jaime-Garcia b a Agricultural Research Service, USDA, United States b Department of Plant Sciences contamination, in part, by direct effects on the causative fungi. As climate shifts, so do the complex and in irrigated hot deserts. In temperate regions, contamination may be severe during drought. The contamination

Cotty, Peter J.

309

DTECTEUR DE CONTAMINATION RADIOACTIVE Par M. BRIRE et J. WEILL,  

E-Print Network [OSTI]

623. D�TECTEUR DE CONTAMINATION RADIOACTIVE Par M. BRI�RE et J. WEILL, Division des Constructions rapidement sur leurs mains, chaussures et vêtements toute trace de contamination. Le principe utilisé permet'utilisation. LE JOURNAL DE PHYSIQUE ET LE RADIUM. TOME 14, NOVEMBRE 1953, , Le détecteur de contamination

Paris-Sud XI, Université de

310

Structure of Turbulence in Katabatic Flows below and above the Wind-Speed Maximum  

E-Print Network [OSTI]

Measurements of small-scale turbulence made over the complex-terrain atmospheric boundary layer during the MATERHORN Program are used to describe the structure of turbulence in katabatic flows. Turbulent and mean meteorological data were continuously measured at multiple levels at four towers deployed along the East lower slope (2-4 deg) of Granite Mountain. The multi-level observations made during a 30-day long MATERHORN-Fall field campaign in September-October 2012 allowed studying of temporal and spatial structure of katabatic flows in detail, and herein we report turbulence and their variations in katabatic winds. Observed vertical profiles show steep gradients near the surface, but in the layer above the slope jet the vertical variability is smaller. It is found that the vertical (normal to the slope) momentum flux and horizontal (along the slope) heat flux in a slope-following coordinate system change their sign below and above the wind maximum of a katabatic flow. The vertical momentum flux is directed...

Grachev, Andrey A; Di Sabatino, Silvana; Fernando, Harindra J S; Pardyjak, Eric R; Fairall, Christopher W

2015-01-01T23:59:59.000Z

311

Assessment of the genotoxic potential of contaminated estuarine sediments in fish peripheral blood: Laboratory versus in situ studies  

SciTech Connect (OSTI)

Juvenile Senegalese soles (Solea senegalensis) were exposed to estuarine sediments through 28-day laboratory and in situ (field) bioassays. The sediments, collected from three distinct sites (a reference plus two contaminated) of the Sado Estuary (W Portugal) were characterized for total organic matter, redox potential, fine fraction and for the levels of metals, polycyclic aromatic hydrocarbons (PAHs) and organochlorines, namely polychlorinated biphenyls (PCBs) and dichloro diphenyl tricholoethane plus its main metabolites (DDTs). Genotoxicity was determined in whole peripheral blood by the single-cell gel electrophoresis (SCGE or 'comet') assay and by scoring erythrocytic nuclear abnormalities (ENA). Analysis was complemented with the determination of lipid peroxidation in blood plasma by the thiobarbituric acid reactive substances (TBARS) protocol and cell type sorting. The results showed that exposure to contaminated sediments induced DNA fragmentation and clastogenesis. Still, laboratory exposure to the most contaminated sediment revealed a possible antagonistic effect between metallic and organic contaminants that might have been enhanced by increased bioavailability. The laboratory assay caused a more pronounced increase in ENA whereas a very significant increase in DNA fragmentation was observed in field-tested fish exposed to the reference sediment, which is likely linked to increased lipid peroxidation that probably occurred due to impaired access to food. Influence of natural pathogens was ruled out by unaltered leukocyte counts. The statistical integration of data correlated lipid peroxidation with biological variables such as fish length and weight, whereas the genotoxicity biomarkers were more correlated to sediment contamination. It was demonstrated that laboratory and field bioassays for the risk assessment of sediment contamination may yield different genotoxicity profiles although both provided results that are in overall accordance with sediment contamination levels. While field assays may provide more ecologically relevant data, the multiple environmental variables may produce sufficient background noise to mask the true effects of contamination.

Costa, Pedro M., E-mail: pmcosta@fct.unl.pt [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Neuparth, Teresa S. [CIIMAR-Centro Interdisciplinar de Investigacao Marinha e Ambiental, Laboratorio de Toxicologia Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto (Portugal)] [CIIMAR-Centro Interdisciplinar de Investigacao Marinha e Ambiental, Laboratorio de Toxicologia Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto (Portugal); Caeiro, Sandra [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal) [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Departamento de Ciencias e Tecnologia, Universidade Aberta, Rua da Escola Politecnica, 141, 1269-001 Lisboa (Portugal); Lobo, Jorge [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)] [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Martins, Marta; Ferreira, Ana M.; Caetano, Miguel; Vale, Carlos [IPIMAR-INRB, Instituto Nacional dos Recursos Biologicos, Avenida de Brasilia, 1449-006 Lisboa (Portugal)] [IPIMAR-INRB, Instituto Nacional dos Recursos Biologicos, Avenida de Brasilia, 1449-006 Lisboa (Portugal); Angel DelValls, T. [UNESCO/UNITWIN/WiCop Chair-Departamento de Quimica Fisica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cadiz, Poligono rio San Pedro s/n, 11510 Puerto Real, Cadiz (Spain)] [UNESCO/UNITWIN/WiCop Chair-Departamento de Quimica Fisica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cadiz, Poligono rio San Pedro s/n, 11510 Puerto Real, Cadiz (Spain); Costa, Maria H. [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)] [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

2011-01-15T23:59:59.000Z

312

Analyzing risk and uncertainty for improving water distribution system security from malevolent water supply contamination events  

E-Print Network [OSTI]

. Fig. 4.11. Tank level time series. Initial Storage Tank Level 0.00 0.05 0.10 0.15 0.20 0.25 30 31 32 33 34 35 36 37 Head (m) PDF Val u e Tank Level Time Series 104 105 106 107 108 109 110 111 112 0 10203040506070 Hours H ead ( m ) 29 In the case... ANALYZING RISK AND UNCERTAINTY FOR IMPROVING WATER DISTRIBUTION SYSTEM SECURITY FROM MALEVOLENT WATER SUPPLY CONTAMINATION EVENTS A Thesis by JACOB MANUEL TORRES Submitted to the Office of Graduate Studies of Texas A&M...

Torres, Jacob Manuel

2009-05-15T23:59:59.000Z

313

Effect of immiscible liquid contaminants on P-wave transmission through natural aquifer samples  

SciTech Connect (OSTI)

We performed core-scale laboratory experiments to examine the effect of non-aqueous phase liquid (NAPL) contaminants on P-wave velocity and attenuation in heterogeneous media. This work is part of a larger project to develop crosswell seismic methods for minimally invasive NAPL detection. The test site is the former DOE Pinellas Plant in Florida, which has known NAPL contamination in the surficial aquifer. Field measurements revealed a zone of anomalously high seismic attenuation, which may be due to lithology and/or contaminants (NAPL or gas phase). Intact core was obtained from the field site, and P-wave transmission was measured by the pulse-transmission technique with a 500 kHz transducer. Two types of samples were tested: a clean fine sand from the upper portion of the surficial aquifer, and clayey-silty sand with shell fragments and phosphate nodules from the lower portion. Either NAPL trichloroethene or toluene was injected into the initially water-saturated sample. Maximum NAPL saturations ranged from 30 to 50% of the pore space. P-wave velocity varied by approximately 4% among the water-saturated samples, while velocities decreased by 5 to 9% in samples at maximum NAPL saturation compared to water-saturated conditions. The clay and silt fraction as well as the larger scatterers in the clayey-silty sands apparently caused greater P-wave attenuation compared to the clean sand. The presence of NAPLs caused a 34 to 54% decrease in amplitudes of the first arrival. The central frequency of the transmitted energy ranged from 85 to 200 kHz, and was sensitive to both grain texture and presence of NAPL. The results are consistent with previous trends observed in homogeneous sand packs. More data will be acquired to interpret P-wave tomograms from crosswell field measurements, determine the cause of high attenuation observed in the field data and evaluate the sensitivity of seismic methods for NAPL detection.

Geller, Jil T.; Ajo-Franklin, Jonathan B.; Majer, Ernest L.

2003-01-31T23:59:59.000Z

314

Fixation of Radiological Contamination; International Collaborative Development  

SciTech Connect (OSTI)

A cooperative international project was conducted by the Idaho National Laboratory (INL) and the United Kingdom’s National Nuclear Laboratory (NNL) to integrate a capture coating with a high performance atomizing process. The initial results were promising, and lead to further trials. The somewhat longer testing and optimization process has resulted in a product that could be demonstrated in the field to reduce airborne radiological dust and contamination.

Rick Demmer

2013-03-01T23:59:59.000Z

315

Purifying contaminated water. [DOE patent application  

DOE Patents [OSTI]

Process is presented for removing biorefactory compounds from contaminated water (e.g., oil shale retort waste-water) by contacting same with fragmented raw oil shale. Biorefractory removal is enhanced by preactivating the oil shale with at least one member of the group of carboxylic acids, alcohols, aldehydes, ketones, ethers, amines, amides, sulfoxides, mixed ether-esters and nitriles. Further purification is obtained by stripping, followed by biodegradation and removal of the cells.

Daughton, C.G.

1981-10-27T23:59:59.000Z

316

Bioremediation of uranium contaminated soils and wastes  

SciTech Connect (OSTI)

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (1) stabilization of uranium and toxic metals with reduction in waste volume and (2) removal and recovery of uranium and toxic metals from wastes and contaminated soils. Stabilization of uranium and toxic metals in wastes is accomplished by exploiting the unique metabolic capabilities of the anaerobic bacterium, Clostridium sp. The radionuclides and toxic metals are solubilized by the bacteria directly by enzymatic reductive dissolution, or indirectly due to the production of organic acid metabolites. The radionuclides and toxic metals released into solution are immobilized by enzymatic reductive precipitation, biosorption and redistribution with stable mineral phases in the waste. Non-hazardous bulk components of the waste volume. In the second process uranium and toxic metals are removed from wastes or contaminated soils by extracting with the complexing agent citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, followed by photochemical degradation of the uranium citrate complex which is recalcitrant to biodegradation. The toxic metals and uranium are recovered in separate fractions for recycling or for disposal. The use of combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in clean-up and disposal costs.

Francis, A.J.

1998-12-31T23:59:59.000Z

317

Initial characterization of a highly contaminated high explosives outfall in preparation for in situ bioremediation  

SciTech Connect (OSTI)

In situ bioremediation is a viable, cost-effective treatment for environmental contamination of many kinds. The feasibility of using biological techniques to remediate soils contaminated with high explosives (HE) requires laboratory evaluation before proceeding to a larger scale field operation. Laboratory investigations have been conducted at pilot scale which indicate that an anaerobic process could be successful at reducing levels of HE, primarily HMX, RDX and TNT, in contaminated soils. A field demonstration project has been designed to create an anaerobic environment for the degradation of HE materials. The first step in this project, initial characterization of the test area, was conducted and is the subject of this report. The levels of HE compounds found in the samples from the test area were higher than the EPA Method 8330 was able to extract without subsequent re-precipitation; therefore, a new method was developed using a superior extractant system. The test area sampling design was relatively simple as one might expect in an initial characterization. A total of 60 samples were each removed to a depth of 4 inches using a 1 inch diameter corer. The samples were spaced at relatively even intervals across a 20 foot cross-section through the middle of four 7-foot-long adjacent plots which are designed to be a part of an in situ bioremediation experiment. Duplicate cores were taken from each location for HE extraction and analysis in order to demonstrate and measure the heterogeneity of the contamination. Each soil sample was air dried and ball-milled to provide a homogeneous solid for extraction and analysis. Several samples had large consolidated pieces of what appeared to be solid HE. These were not ball-milled due to safety concerns, but were dissolved and the solutions were analyzed. The new extraction method was superior in that results obtained for several of the contaminants were up to 20 times those obtained with the EPA extraction method. The results obtained from this study showed that the test area contamination is extremely heterogeneous, and that it contains extremely high levels of the three major contaminants, HMX, RDX and TNT. The potential for success of a bioremediation strategy is discussed.

Betty A. Strietelmeier; Patrick J. Coyne; Patricia A. Leonard; W. Lamar Miller; Jerry R. Brian

1999-12-01T23:59:59.000Z

318

Operating and life-cycle costs for uranium-contaminated soil treatment technologies  

SciTech Connect (OSTI)

The development of a nuclear industry in the US required mining, milling, and fabricating a large variety of uranium products. One of these products was purified uranium metal which was used in the Savannah River and Hanford Site reactors. Most of this feed material was produced at the US Department of Energy (DOE) facility formerly called the Feed Materials Production Center at Fernald, Ohio. During operation of this facility, soils became contaminated with uranium from a variety of sources. To avoid disposal of these soils in low-level radioactive waste burial sites, increasing emphasis has been placed on the remediating soils contaminated with uranium and other radionuclides. To address remediation and management of uranium-contaminated soils at sites owned by DOE, the DOE Office of Technology Development (OTD) evaluates and compares the versatility, efficiency, and economics of various technologies that may be combined into systems designed to characterize and remediate uranium-contaminated soils. Each technology must be able to (1) characterize the uranium in soil, (2) decontaminate or remove uranium from soil, (3) treat or dispose of resulting waste streams, (4) meet necessary state and federal regulations, and (5) meet performance assessment objectives. The role of the performance assessment objectives is to provide the information necessary to conduct evaluations of the technologies. These performance assessments provide the basis for selecting the optimum system for remediation of large areas contaminated with uranium. One of the performance assessment tasks is to address the economics of full-scale implementation of soil treatment technologies. The cost of treating contaminated soil is one of the criteria used in the decision-making process for selecting remedial alternatives.

Douthat, D.M.; Armstrong, A.Q. [Oak Ridge National Lab., TN (United States). Health Sciences Research Div.; Stewart, R.N. [Univ. of Tennessee, Knoxville, TN (United States)

1995-09-01T23:59:59.000Z

319

Effect of Coal Contaminants on Solid Oxide Fuel System Performance and Service Life  

SciTech Connect (OSTI)

The U.S. Department of Energy's SECA program envisions the development of high-efficiency, low-emission, CO{sub 2} sequestration-ready, and fuel-flexible technology to produce electricity from fossil fuels. One such technology is the integrated gasification-solid oxide fuel cell (SOFC) that produces electricity from the gas stream of a coal gasifier. SOFCs have high fuel-to-electricity conversion efficiency, environmental compatibility (low NO{sub x} production), and modularity. Naturally occurring coal has many impurities and some of these impurities end in the fuel gas stream either as a vapor or in the form of fine particulate matter. Establishing the tolerance limits of SOFCs for contaminants in the coal-derived gas will allow proper design of the fuel feed system that will not catastrophically damage the SOFC or allow long-term cumulative degradation. The anodes of Ni-cermet-based SOFCs are vulnerable to degradation in the presence of contaminants that are expected to be present in a coal-derived fuel gas stream. Whereas the effects of some contaminants such as H{sub 2}S, NH{sub 3} and HCl have been studied, the effects of other contaminants such as As, P, and Hg have not been ascertained. The primary objective of this study was to determine the sensitivity of the performance of solid oxide fuel cells to trace level contaminants present in a coal-derived gas stream in the temperature range 700 to 900 C. The results were used to assess catastrophic damage risk and long-term cumulative effects of the trace contaminants on the lifetime expectancy of SOFC systems fed with coal-derived gas streams.

Gopala Krishnan; P. Jayaweera; J. Bao; J. Perez; K. H. Lau; M. Hornbostel; A. Sanjurjo; J. R. Albritton; R. P. Gupta

2008-09-30T23:59:59.000Z

320

Sulfur Polymer Stabilization/Solidification Treatability Study of Mercury Contaminated Soil from the Y-12 Site  

SciTech Connect (OSTI)

As a result of past operations, the Department of Energy’s (DOE) Oak Ridge Y-12 National Security Complex (Y-12 Plant) has extensive mercury-contamination in building structures, soils, storm sewer sediments, and stream sediments, which are a source of pollution to the local ecosystem. Because of mercury’s toxicity and potential impacts on human health and the environment, DOE continues to investigate and implement projects to support the remediation of the Y-12 site.URS and #9122;CH2M Oak Ridge LLC (UCOR) under its prime contract with DOE has cleanup responsibilities on the DOE Oak Ridge Reservation and is investigating potential mercury-contaminated soil treatment technologies through an agreement with Babcock and Wilcox (B and W) Y-12, the Y-12 operating contractor to DOE. As part of its investigations, UCOR has subcontracted with Brookhaven National Laboratory (BNL) to conduct laboratory-scale studies evaluating the applicability of the Sulfur Polymer Stabilization/Solidification (SPSS) process using surrogate and actual mixed waste Y-12 soils containing mercury (Hg) at 135, 2,000, and 10,000 ppm.SPSS uses a thermoplastic sulfur binder to convert Hg to stable mercury sulfide (HgS) and solidifies the chemically stable product in a monolithic solid final waste form to reduce dispersion and permeability. Formulations containing 40 – 60 dry wt% Y-12 soil were fabricated and samples were prepared in triplicate for Environmental Protection Agency Toxicity Characteristic Leaching Procedure (TCLP) testing by an independent laboratory. Those containing 50 and 60 wt% soil easily met the study criteria for maximum allowable Hg concentrations (47 and 1 ppb, respectively compared with the TCLP limit of 200 ppb Hg). The lowest waste loading of 40 wt% yielded TCLP Hg concentrations slightly higher (240 ppb) than the allowable limit. Since the Y-12 soil tended to form clumps, the improved leaching at higher waste loadings was probably due to reduction in particle size from friction of the soil mixing, which creates more surface area for chemical conversion. This was corroborated by the fact that the same waste loading pre-treated by ball milling to reduce particle size prior to SPSS processing yielded TCLP concentrations almost 30 times lower, and at 8.5 ppb Hg was well below EPA limits. Pre-treatment by ball milling also allowed a reduction in the time required for stabilization, thus potentially reducing total process times by 30%.Additional performance testing was conducted including measurement of compressive strength to confirm mechanical integrity and immersion testing to determine the potential impacts of storage or disposal under saturated conditions. For both surrogate and actual Y-12 treated soils, waste form compressive strengths ranged between 2,300 and 6,500 psi, indicating very strong mechanical integrity (a minimum of greater than 40 times greater than the NRC guidance for low-level radioactive waste). In general, compressive strength increases with waste loading as the soil acts as an aggregate in the sulfur concrete waste forms. No statistically significant loss in strength was recorded for the 30 and 40 wt% surrogate waste samples and only a minor reduction in strength was measured for the 43 wt% waste forms. The 30 wt% Y-12 soil did not show a significant loss in strength but the 50 wt% samples were severely degraded in immersion due to swelling of the clay soil. The impact on Hg leaching, if any, was not determined.

Kalb P.; Milian, L.; Yim, S. P.

2012-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Final work plan : phase II investigation of potential contamination at the former CCC/USDA grain storage facility in Savannah, Missouri.  

SciTech Connect (OSTI)

From approximately 1949 until 1970, the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) operated a grain storage facility on federally owned property approximately 0.25 mi northwest of Savannah, Missouri (Figure 1.1). During this time, commercial grain fumigants containing carbon tetrachloride were commonly used by the CCC/USDA and the private grain storage industry to preserve grain in their facilities. In November 1998, carbon tetrachloride was detected in a private well (Morgan) roughly 50 ft south of the former CCC/USDA facility, as a result of statewide screening of private wells near former CCC/USDA facilities, conducted in Missouri by the U.S. Environmental Protection Agency (EPA 1999). The 1998 and subsequent investigations by the EPA and the Missouri Department of Natural Resources (MoDNR) confirmed the presence of carbon tetrachloride in the Morgan well, as well as in a second well (on property currently occupied by the Missouri Department of Transportation [MoDOT]) described as being approximately 400 ft east of the former CCC/USDA facility. The identified concentrations in these two wells were above the EPA maximum contaminant level (MCL) and the Missouri risk-based corrective action default target level (MRBCA DTL) values of 5.0 {micro}g/L for carbon tetrachloride in water used for domestic purposes (EPA 1999; MoDNR 2000a,b, 2006). Because the observed contamination in the Morgan and MoDOT wells might be linked to the past use of carbon tetrachloride-based fumigants at its former grain storage facility, the CCC/USDA is conducting an investigation to (1) characterize the source(s), extent, and factors controlling the subsurface distribution and movement of carbon tetrachloride at Savannah and (2) evaluate the potential risks to human health, public welfare, and the environment posed by the contamination. This work is being performed in accord with the Intergovernmental Agreement established between the Farm Service Agency of the USDA and the MoDNR, to address carbon tetrachloride contamination potentially associated with a number of former CCC/USDA grain storage facilities in Missouri. The site characterization at Savannah is being conducted on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. The investigation at Savannah is being conducted in phases. This approach is being used by the CCC/USDA and Argonne, with the approval of the MoDNR, so that information obtained and interpretations developed during each incremental stage of the investigation can be used most effectively to guide subsequent phases of the program. Phase I of the Savannah program was conducted in October-November 2007 and January 2008 (Argonne 2007a, 2008). This site-specific Work Plan provides a brief summary of the Phase I findings and the results of groundwater level monitoring that has been ongoing since completion of the Phase I study and also outlines technical objectives, investigation tasks, and investigation methods for Phase II of the site characterization at Savannah.

LaFreniere, L. M.; Environmental Science Division

2010-08-16T23:59:59.000Z

322

Analysis of Optics and Mask Contamination in SEMATECH EUV Micro-Exposure Tools  

E-Print Network [OSTI]

Analysis of Optics and Mask Contamination in SEMATECHMioro^Exposure Tools IEUVI Optics Contamination/Lifetime TWG

Wuest, Andrea

2008-01-01T23:59:59.000Z

323

Two- and Three-Dimensional Depiction of Subsurface Geology Using Commercial Software for Support of Groundwater Contaminant Fate and Transport Analysis - 13345  

SciTech Connect (OSTI)

Groundwater contamination by hexavalent chromium and other nuclear reactor operation-related contaminants has resulted in the need for groundwater remedial actions within the Hanford Site reactor areas (the Hanford Site 100 Area). The large geographic extent of the resultant contaminant plumes requires an extensive level of understanding of the aquifer structure, characteristics, and configuration to support assessment and design of remedial alternatives within the former 100-D, 100-H, and 100-K reactor areas. The authors have prepared two- and three-dimensional depictions of the key subsurface geologic structures at two Hanford Site reactor operable units (100-K and 100-D/H). These depictions, prepared using commercial-off-the-shelf (COTS) visualization software, provide a basis for expanding the understanding of groundwater contaminant migration pathways, including identification of geologically-defined preferential groundwater flow pathways. These identified preferential flow pathways support the conceptual site model and help explain both historical and current contaminant distribution and transport. (authors)

Ivarson, Kristine A. [North Wind, Inc. Richland, Washington 99352 (United States)] [North Wind, Inc. Richland, Washington 99352 (United States); Miller, Charles W.; Arola, Craig C. [CH2M HILL Plateau Remediation Company, Richland, Washington 99352 (United States)] [CH2M HILL Plateau Remediation Company, Richland, Washington 99352 (United States)

2013-07-01T23:59:59.000Z

324

Process for measuring low cadmium levels in blood and other biological specimens  

DOE Patents [OSTI]

A process for measuring low levels of cadmium in blood and other biological specimens is provided without interference from high levels of alkali metal contaminants by forming an aqueous solution and without contamination by environmental cadmium absent the proteins from the specimen, selectively removing cadmium from the aqueous solution on an anion exchange resin, thereby removing the alkali metal contaminants, resolubilizing cadmium from the resin to form a second solution and analyzing the second solution for cadmium, the process being carried out in a cadmium-free environment.

Peterson, David P. (Orland Park, IL); Huff, Edmund A. (Lemont, IL); Bhattacharyya, Maryka H. (Naperville, IL)

1994-01-01T23:59:59.000Z

325

Effect of dietary calcium and phosphorus levels on performance and bone development of large-framed developing boars  

E-Print Network [OSTI]

quantitative carcass measurement among boars fed the six treatment diets. Bone breaking load (BKL) of the femurs increased quadratically (P&. 01) as mineral levels increased with a predicted maximum response at 1. 21X calcium and 1. 01X phosphorus. Breaking..., feed intake and feed efficiency for developing boars. However, higher dietary phosphorus levels were needed for maximum bone develop- ment. Maximum response was obtained from the following phosphorus levels: bone breaking load ranged from 1. 01X...

Robinson, Robert Glen

1975-01-01T23:59:59.000Z

326

A Review of Removable Surface Contamination on Radioactive Materials Transportation Containers  

SciTech Connect (OSTI)

This report contains the results of a study sponsored by the U.S. Nuclear Regulatory Commission (NRC) of removable surface contamination on radioactive materials transportation containers. The purpose of the study is to provide information to the NRC during their review of existing regulations. Data was obtained from both industry and literature on three major topics: 1) radiation doses, 2) economic costs, and 3) contamination frequencies. Containers for four categories of radioactive materials are considered including radiopharmaceuticals, industrial sources, nuclear fuel cycle materials, and low-level radioactive waste. Assumptions made in this study use current information to obtain realistic yet conservative estimates of radiation dose and economic costs. Collective and individual radiation doses are presented for each container category on a per container basis. Total doses, to workers and the public, are also presented for spent fuel cask and low-level waste drum decontamination. Estimates of the additional economic costs incurred by lowering current limits by factors of 10 and 100 are presented. Current contamination levels for each category of container are estimated from the data collected. The information contained in this report is designed to be useful to the NRC in preparing their recommendations for new regulations.

Kennedy, Jr, W. E.; Watson, E. C.; Murphy, D. W.; Harrer, B. J.; Harty, R.; Aldrich, J. M.

1981-05-01T23:59:59.000Z

327

Closure End States for Facilities, Waste Sites, and Subsurface Contamination - 12543  

SciTech Connect (OSTI)

The United States (U.S.) Department of Energy (DOE) manages the largest groundwater and soil cleanup effort in the world. DOE's Office of Environmental Management (EM) has made significant progress in its restoration efforts at sites such as Fernald and Rocky Flats. However, remaining sites, such as Savannah River Site, Oak Ridge Site, Hanford Site, Los Alamos, Paducah Gaseous Diffusion Plant, Portsmouth Gaseous Diffusion Plant, and West Valley Demonstration Project possess the most complex challenges ever encountered by the technical community and represent a challenge that will face DOE for the next decade. Closure of the remaining 18 sites in the DOE EM Program requires remediation of 75 million cubic yards of contaminated soil and 1.7 trillion gallons of contaminated groundwater, deactivation and decommissioning (D and D) of over 3000 contaminated facilities and thousands of miles of contaminated piping, removal and disposition of millions of cubic yards of legacy materials, treatment of millions of gallons of high level tank waste and disposition of hundreds of contaminated tanks. The financial obligation required to remediate this volume of contaminated environment is estimated to cost more than 7% of the to-go life-cycle cost. Critical in meeting this goal within the current life-cycle cost projections is defining technically achievable end states that formally acknowledge that remedial goals will not be achieved for a long time and that residual contamination will be managed in the interim in ways that are protective of human health and environment. Formally acknowledging the long timeframe needed for remediation can be a basis for establishing common expectations for remedy performance, thereby minimizing the risk of re-evaluating the selected remedy at a later time. Once the expectations for long-term management are in place, remedial efforts can be directed towards near-term objectives (e.g., reducing the risk of exposure to residual contamination) instead of focusing on long-term cleanup requirements. An acknowledgement of the long timeframe for complete restoration and the need for long-term management can also help a site transition from the process of pilot testing different remedial strategies to selecting a final remedy and establishing a long-term management and monitoring approach. This approach has led to cost savings and the more efficient use of resources across the Department of Defense complex and at numerous industrial sites across the U.S. Defensible end states provide numerous benefits for the DOE environmental remediation programs including cost-effective, sustainable long-term monitoring strategies, remediation and site transition decision support, and long-term management of closure sites. (authors)

Gerdes, Kurt; Chamberlain, Grover; Whitehurst, Latrincy; Marble, Justin [Office of Groundwater and Soil Remediation, U.S. Department of Energy, Washington, DC 20585 (United States); Wellman, Dawn [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Deeb, Rula; Hawley, Elisabeth [ARCADIS U.S., Inc., Emeryville, CA 94608 (United States)

2012-07-01T23:59:59.000Z

328

Monitoring ecological recovery in a stream impacted by contaminated groundwater  

SciTech Connect (OSTI)

Past in-ground disposal practices in Bear Creek Valley resulted in contamination of Bear Creek and consequent ecological damage. A biological monitoring program initiated in 1984 has evaluated the effectiveness of the extensive remedial actions undertaken to address contamination sources. Elements of the monitoring program included toxicity testing with fish and invertebrates, bioaccumulation monitoring, and instream monitoring of streambed invertebrate and fish communities. In the mid 1980`s, toxicity tests on stream water indicated that the headwaters of the stream were acutely toxic to fish and aquatic invertebrates as a result of infiltration of a metal-enriched groundwater from ponds used to dispose of acid wastes. Over a twelve year period, measurable toxicity in the headwaters decreased, first becoming non-toxic to larval fish but still toxic to invertebrates, then becoming intermittently toxic to invertebrates. By 1997, episodic toxicity was infrequent at the site that was acutely toxic at the start of the study. Recovery in the fish community followed the pattern of the toxicity tests. Initially, resident fish populations were absent from reaches where toxicity was measured, but as toxicity to fish larvae disappeared, the sites in upper Bear Creek were colonized by fish. The Tennessee dace, an uncommon species receiving special protection by the State of Tennessee, became a numerically important part of the fish population throughout the upper half of the creek, making Bear Creek one of the most significant habitats for this species in the region. Although by 1990 fish populations were comparable to those of similar size reference streams, episodic toxicity in the headwaters coincided with a recruitment failure in 1996. Bioaccumulation monitoring indicated the presence of PCBs and mercury in predatory fish in Bear Creek, and whole forage fish contained elevated levels of cadmium, lead, lithium, nickel, mercury, and uranium.

Southworth, G.R.; Cada, G.F.; Kszos, L.A.; Peterson, M.J.; Smith, J.G. [and others

1997-11-01T23:59:59.000Z

329

BIOREMEDIATION OF URANIUM CONTAMINATED SOILS AND WASTES.  

SciTech Connect (OSTI)

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (i) stabilization of uranium and toxic metals with reduction in waste volume and (ii) removal and recovery of uranium and toxic metals from wastes and contaminated soils. Stabilization of uranium and toxic metals in wastes is accomplished by exploiting the unique metabolic capabilities of the anaerobic bacterium, Clostridium sp. The radionuclides and toxic metals are solubilized by the bacteria directly by enzymatic reductive dissolution, or indirectly due to the production of organic acid metabolites. The radionuclides and toxic metals released into solution are immobilized by enzymatic reductive precipitation, biosorption and redistribution with stable mineral phases in the waste. Non-hazardous bulk components of the waste such as Ca, Fe, K, Mg and Na released into solution are removed, thus reducing the waste volume. In the second process uranium and toxic metals are removed from wastes or contaminated soils by extracting with the complexing agent citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, followed by photochemical degradation of the uranium citrate complex which is recalcitrant to biodegradation. The toxic metals and uranium are recovered in separate fractions for recycling or for disposal. The use of combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in clean-up and disposal costs.

FRANCIS,A.J.

1998-09-17T23:59:59.000Z

330

Portable spotter for fluorescent contaminants on surfaces  

DOE Patents [OSTI]

A portable fluorescence-based spotter for polynuclear aromatic hydrocarbon contamination on personnel and work area surfaces under ambient lighting conditions is provided. This instrument employs beam modulation and phase sensitive detection for discriminating between fluorescence from organic materials from reflected background light and inorganic fluorescent material. The device uses excitation and emission filters to provide differentiation between classes of aromatic organic compounds. Certain inorganic fluorescent materials, including heavy metal compounds, may also be distinguished from the organic compounds, despite both having similar optical properties.

Schuresko, Daniel D. (Oak Ridge, TN)

1980-01-01T23:59:59.000Z

331

Radiological hazards of alpha-contaminated waste  

SciTech Connect (OSTI)

The radiological hazards of alpha-contaminated wastes are discussed in this overview in terms of two components of hazard: radiobiological hazard, and radioecological hazard. Radiobiological hazard refers to human uptake of alpha-emitters by inhalation and ingestion, and the resultant dose to critical organs of the body. Radioecological hazard refers to the processes of release from buried wastes, transport in the environment, and translocation to man through the food chain. Besides detailing the sources and magnitude of hazards, this brief review identifies the uncertainties in their estimation, and implications for the regulatory process.

Rodgers, J.C.

1982-01-01T23:59:59.000Z

332

Hydrogen Contamination Detector Workshop | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Year in3.pdfEnergy Health and ProductivityEnergyEnergyHybridAnalysisContamination Detector

333

Effect of contamination on the water separability of steam turbine oils  

SciTech Connect (OSTI)

The effect on water separability of three commercial steam turbine oils when contaminated with engine oil and/or a commercially available enhancement additive (designated as Additive X in this paper) for automotive lubricants was investigated. Additive X is an after-market lubricating oil supplement containing conventional crankcase type additives. All three oils showed degradation of water separability when contaminated with as little as 500 ppm (the ppm unit used through out this paper is ppm m/m.) of Additive X alone, as little as 500 ppm of engine oil alone, or 300 ppm of Additive X and 300 ppm of engine oil. It is speculated that the contamination affects water separability because of its calcium-based detergent component. The contamination at these levels in the steam turbine oil is not easily detected by trace metal analysis commonly used in rapid oil analysis programs. This is of concern because Additive X and engine oil are often used in industry to coat bearings during turbine generator maintenance. This study indicates that such practices could result in unsatisfactory water separation characteristics of the turbine oil. 3 refs., 2 figs., 6 tabs.

Li, Tsong-Dsu; Mansfield, J.M. [Texaco Port Arthur Research Lab., TX (United States)

1995-01-01T23:59:59.000Z

334

Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport  

SciTech Connect (OSTI)

Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, partial pressure of carbon dioxide, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. In this final report, we provide detailed descriptions of our results from this three-year study, completed in 2012 following a one-year no cost extension.

Chorover, Jon; Perdrial, Nico; Mueller, Karl; Strepka, Caleb; Oà ƒ  ¢Ã ‚  € à ‚  ™ Day, Peggy; Rivera, Nelson; Um, Wooyong; Chang, Hyun-Shik; Steefel, Carl; Thompson, Aaron

2012-11-05T23:59:59.000Z

335

CO2 levels during the greenhouse of the Paleocene  

E-Print Network [OSTI]

to reconstruct CO2 concentrations during this period of global warming 56 million years ago. 56 million year oldCO2 levels during the greenhouse of the Paleocene Eocene Thermal Maximum (PETM) Francesca A. Mc, Boulder #12;Estimating paleopCO2 0 5 10 15 20 25 30 0 500 1000 1500 2000 2500 3000 Meter Level, start

Shull, Kenneth R.

336

UPDATE: Community meeting on February 6, 2003 Cross-sectional Exposure Assessment of Environmental Contaminants in Churchill County, Nevada  

E-Print Network [OSTI]

on Human Exposure to Environmental Chemicals. · Arsenic levels were elevated in Churchill CountyUPDATE: Community meeting on February 6, 2003 Cross-sectional Exposure Assessment of Environmental Contaminants in Churchill County, Nevada Centers for Disease Control and Prevention Study Results

337

RESULTS FOR THE THIRD QUARTER 2007 TANK 50H WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS  

SciTech Connect (OSTI)

The Saltstone Facility is designed and permitted to immobilize and dispose of low-level radioactive and hazardous liquid waste (salt solution) remaining from the processing of radioactive material at the Savannah River Site. Low activity wastewater streams from the Effluent Treatment Project (ETP), H-Canyon, and the high level waste (HLW) storage tanks, are stored as a mixture in Tank 50H until it can be pumped to the Saltstone Facility for treatment and disposal. Specific waste acceptance criteria (WAC) must be met for the transfer of low-level aqueous waste from Tank 50H to the Saltstone Facility. Low level waste which meets the WAC can be transferred, stored and treated in the Saltstone Production Facility (SPF) for subsequent disposal as saltstone in the Saltstone Disposal Facility (SDF). Waste Solidification Engineering (WSE) has requested through a Technical Task Request (TTR) that the Savannah River National Laboratory (SRNL) measure the concentrations of chemical and radionuclide contaminants listed in the currently approved Saltstone Waste Acceptance Criteria (WAC). A Task Technical and Quality Assurance Plan and Analytical Study Plan has been written for this request. WAC determinations are needed on a quarterly basis for chemical contaminants and every first and third quarter for radioactive contaminants. This memorandum presents the results for the chemical and radionuclide contaminants in the third quarter, from the samples taken from Tank 50 in September, 2007.

Zeigler, K; Ned Bibler, N

2008-07-11T23:59:59.000Z

338

Integrated process analysis of treatment systems for mixed low level waste  

SciTech Connect (OSTI)

Selection of technologies to be developed for treatment of DOE`s mixed low level waste (MLLW) requires knowledge and understanding of the expected costs, schedules, risks, performance, and reliability of the total engineered systems that use these technologies. Thus, an integrated process analysis program was undertaken to identify the characteristics and needs of several thermal and nonthermal systems. For purposes of comparison, all systems were conceptually designed for a single facility processing the same amount of waste at the same rate. Thirty treatment systems were evaluated ranging from standard incineration to innovative thermal systems and innovative nonthermal chemical treatment. Treating 236 million pounds of waste in 20 years through a central treatment was found to be the least costly option with total life cycle cost ranging from $2.1 billion for a metal melting system to $3.9 billion for a nonthermal acid digestion system. Little cost difference exists among nonthermal systems or among thermal systems. Significant cost savings could be achieved by working towards maximum on line treatment time per year; vitrifying the final waste residue; decreasing front end characterization segregation and sizing requirements; using contaminated soil as the vitrifying agent; and delisting the final vitrified waste form from Resource Conservation and Recovery Act (RCRA) Land Disposal Restriction (LDR) requirements.

Cooley, C.R. [Dept. of Energy, Washington, DC (United States); Schwinkendorf, W.E. [Lockheed Martin Idaho Technology Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.]|[Sandia National Labs., Albuquerque, NM (United States); Bechtold, T.E. [Lockheed Martin Idaho Technology Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.

1997-10-01T23:59:59.000Z

339

In-situ remediation system and method for contaminated groundwater  

DOE Patents [OSTI]

A system for removing volatile contaminants from a subsurface plume of contamination comprising two sets of wells, a well for injecting a fluid into a saturated zone on one side of the plume and an extracting well for collecting the fluid together with volatilized contaminants from the plume on the other side of the plume. The fluid enables the volatile contaminants to be volatilized and carried therewith through the ground to the extracting well. Injecting and extracting wells are preferably horizontal wells positioned below the plume in the saturated zone and above the plume in the vadose zone, respectively. The fluid may be air or other gas or a gas and liquid mixture depending on the type of contaminant to be removed and may be preheated to facilitate volatilization. Treatment of the volatilized contamination may be by filtration, incineration, atmospheric dispersion or the like. 3 figs.

Corey, J.C.; Looney, B.B.; Kaback, D.S.

1989-05-23T23:59:59.000Z

340

In-situ remediation system and method for contaminated groundwater  

DOE Patents [OSTI]

A system for removing volatile contaminants from a subsurface plume of contamination comprising two sets of wells, a well for injecting a fluid into a saturated zone on one side of the plume and an extracting well for collecting the fluid together with volatilized contaminants from the plume on the other side of the plume. The fluid enables the volatile contaminants to be volatilized and carried therewith through the ground to the extracting well. Injecting and extracting wells are preferably horizontal wells positioned below the plume in the saturated zone and above the plume in the vadose zone, respectively. The fluid may be air or other gas or a gas and liquid mixture depending on the type of contaminant to be removed and may be preheated to facilitate volatilization. Treatment of the volatilized contamination may be by filtration, incineration, atmospheric dispersion or the like.

Corey, John C. (Aiken, SC); Looney, Brian B. (Aiken, SC); Kaback, Dawn S. (Aiken, SC)

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Mixed low-level waste form evaluation  

SciTech Connect (OSTI)

A scoping level evaluation of polyethylene encapsulation and vitreous waste forms for safe storage of mixed low-level waste was performed. Maximum permissible radionuclide concentrations were estimated for 15 indicator radionuclides disposed of at the Hanford and Savannah River sites with respect to protection of the groundwater and inadvertent intruder pathways. Nominal performance improvements of polyethylene and glass waste forms relative to grout are reported. These improvements in maximum permissible radionuclide concentrations depend strongly on the radionuclide of concern and pathway. Recommendations for future research include improving the current understanding of the performance of polymer waste forms, particularly macroencapsulation. To provide context to these estimates, the concentrations of radionuclides in treated DOE waste should be compared with the results of this study to determine required performance.

Pohl, P.I.; Cheng, Wu-Ching; Wheeler, T.; Waters, R.D.

1997-03-01T23:59:59.000Z

342

Detection of contamination of municipal water distribution systems  

DOE Patents [OSTI]

A system for the detection of contaminates of a fluid in a conduit. The conduit is part of a fluid distribution system. A chemical or biological sensor array is connected to the conduit. The sensor array produces an acoustic signal burst in the fluid upon detection of contaminates in the fluid. A supervisory control system connected to the fluid and operatively connected to the fluid distribution system signals the fluid distribution system upon detection of contaminates in the fluid.

Cooper, John F. (Oakland, CA)

2012-01-17T23:59:59.000Z

343

System for the removal of contaminant soil-gas vapors  

DOE Patents [OSTI]

A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources.

Weidner, Jerry R. (Iona, ID); Downs, Wayne C. (Sugar City, ID); Kaser, Timothy G. (Ammon, ID); Hall, H. James (Idaho Falls, ID)

1997-01-01T23:59:59.000Z

344

System for the removal of contaminant soil-gas vapors  

DOE Patents [OSTI]

A system extracts contaminated vapors from soil or other subsurface regions by using changes in barometric pressure to operate sensitive check valves that control air entry and removal from wells in the ground. The system creates an efficient subterranean flow of air through a contaminated soil plume and causes final extraction of the contaminants from the soil to ambient air above ground without any external energy sources. 4 figs.

Weidner, J.R.; Downs, W.C.; Kaser, T.G.; Hall, H.J.

1997-12-16T23:59:59.000Z

345

Characterization of a soil contaminated by oilfield brine  

SciTech Connect (OSTI)

Brine contamination of soil is a common environmental problem associated with the onshore production of oil and gas. A site of extensive contamination in Oklahoma has been characterized using conductimetry, direct potentiometry (pH- and chloride-selective electrodes), and atomic absorption spectrophotometry (for Na{sup +} and Ca{sup 2+}) to determine the extent of the contamination and the efficacy of various remediation technologies.

Al-Mutairi, K.; Harris, T. [Univ. of Tulsa, OH (United States)

1995-12-01T23:59:59.000Z

346

Treatment of Organic-Contaminated Wastewater by Pervaporation  

E-Print Network [OSTI]

TREATMENT OF ORGANIC-CONTAMINATED WASTEWATER BY PERVAPORATION J.G. WIJMANS J. KASCHEMEKAT R.W. BAKER V.L. SIMMONS Research Director Design Engineer President Marketing Director Membrane Technology and Research, Inc., Menlo Park, CA ABSTRACT...-CONTAMINATED WASTEWATER BY PERVAPORATION J.G. WIJMANS Research Director J. KASCHEMEKAT R.W. BAKER V.L. SIMMONS Design Engineer President Marketing Director Membrane Technology and Research, Inc., Menlo Park, CA ABSTRACT The removal and recovery of organic contaminants...

Wijmans, J. G.; Kaschemekat, J.; Baker, R. W.; Simmons, V. L.

347

Normalized Tritium Quantification Approach (NoTQA) a Method for Quantifying Tritium Contaminated Trash and Debris at LLNL  

SciTech Connect (OSTI)

Several facilities and many projects at LLNL work exclusively with tritium. These operations have the potential to generate large quantities of Low-Level Radioactive Waste (LLW) with the same or similar radiological characteristics. A standardized documented approach to characterizing these waste materials for disposal as radioactive waste will enhance the ability of the Laboratory to manage them in an efficient and timely manner while ensuring compliance with all applicable regulatory requirements. This standardized characterization approach couples documented process knowledge with analytical verification and is very conservative, overestimating the radioactivity concentration of the waste. The characterization approach documented here is the Normalized Tritium Quantification Approach (NoTQA). This document will serve as a Technical Basis Document which can be referenced in radioactive waste characterization documentation packages such as the Information Gathering Document. In general, radiological characterization of waste consists of both developing an isotopic breakdown (distribution) of radionuclides contaminating the waste and using an appropriate method to quantify the radionuclides in the waste. Characterization approaches require varying degrees of rigor depending upon the radionuclides contaminating the waste and the concentration of the radionuclide contaminants as related to regulatory thresholds. Generally, as activity levels in the waste approach a regulatory or disposal facility threshold the degree of required precision and accuracy, and therefore the level of rigor, increases. In the case of tritium, thresholds of concern for control, contamination, transportation, and waste acceptance are relatively high. Due to the benign nature of tritium and the resulting higher regulatory thresholds, this less rigorous yet conservative characterization approach is appropriate. The scope of this document is to define an appropriate and acceptable characterization method for quantification of tritium contaminated trash and debris. The characterization technique is applicable to surface and subsurface tritium contaminated materials with surfaces amenable to swiping. Some limitations of this characterization technique are identified.

Dominick, J L; Rasmussen, C L

2008-07-23T23:59:59.000Z

348

LANGMUIR WAVE ACTIVITY: COMPARING THE ULYSSES SOLAR MINIMUM AND SOLAR MAXIMUM ORBITS  

E-Print Network [OSTI]

). The top three panels correspond to the southern segment of the solar minimum orbit; repeated passesLANGMUIR WAVE ACTIVITY: COMPARING THE ULYSSES SOLAR MINIMUM AND SOLAR MAXIMUM ORBITS R. J at the electron plasma frequency) during the solar minimum and solar maximum orbits of Ulysses. At high latitudes

California at Berkeley, University of

349

Comparison of VLF Wave Activity in the Solar Wind During Solar Maximum and Minimum  

E-Print Network [OSTI]

second fast latitude scan (near the solar maximum) with the wave observations during the first fast Experiments (URAP) of Ulysses during its first orbit, which occurred when the solar activity was approachingComparison of VLF Wave Activity in the Solar Wind During Solar Maximum and Minimum: Ulysses

California at Berkeley, University of

350

On the duration of the Paleocene-Eocene thermal maximum Ursula Rohl and Thomas Westerhold  

E-Print Network [OSTI]

On the duration of the Paleocene-Eocene thermal maximum (PETM) Ursula Ro¨hl and Thomas Westerhold of California, Santa Cruz, California 95064, USA [1] The Paleocene-Eocene thermal maximum (PETM) is one of global warming and a massive perturbation of the global carbon cycle from injection of isotopically light

Zachos, James

351

An Optimal Randomized Algorithm for Maximum Tukey Depth Timothy M. Chan  

E-Print Network [OSTI]

An Optimal Randomized Algorithm for Maximum Tukey Depth Timothy M. Chan Abstract We present the first optimal algorithm to compute the maximum Tukey depth (also known as location or halfspace depth , the Tukey depth of a point q IRd is defined as: min{|P | : over all halfspaces containing q}. We

Chan, Timothy M.

352

Beating the maximum cooling limit with graded thermoelectric materials Zhixi Bian and Ali Shakouria  

E-Print Network [OSTI]

.1063/1.2396895 The maximum cooling temperature is one of the perfor- mance parameters for a thermoelectric module. ExcludingBeating the maximum cooling limit with graded thermoelectric materials Zhixi Bian and Ali Shakouria cooling of a single element thermoelectric material cannot be improved by changing its geometry.3

353

Maximum Power Transfer Tracking in a Solar USB Charger for Smartphones  

E-Print Network [OSTI]

chargers do not perform the maximum power point tracking [2], [3] of the solar panel. We excludeMaximum Power Transfer Tracking in a Solar USB Charger for Smartphones Abstract--Battery life poor capacity utilization during solar energy harvesting. In this paper, we propose and demonstrate

Pedram, Massoud

354

Maximum-Power-Point Tracking Method of Photovoltaic Using Only Single Current Sensor  

E-Print Network [OSTI]

» «Solar cell systems» Abstract This paper describes a novel strategy of maximum-power-point tracking point using only a single current sensor, i.e., a Hall-effect CT. Output power of the photovoltaic can-climbing method is employed to seek the maximum power point, using the output power obtained from only the current

Fujimoto, Hiroshi

355

Vegetation and Fire at the Last Glacial Maximum in Tropical South America  

E-Print Network [OSTI]

Chapter 4 Vegetation and Fire at the Last Glacial Maximum in Tropical South America Francis E temperatures. Keywords Charcoal · Last Glacial Maximum · pollen · Quaternary · tropical South America F-mail: Francis.Mayle@ed.ac.uk 89F. Vimeux et al. (eds.), Past Climate Variability in South America

Binford, Michael W.

356

A Basic Thermodynamic Derivation of the Maximum Overburden Pressure Generated in Frost Heave  

E-Print Network [OSTI]

can derive the maximum overburden pressure. A similar argument can also produce the maximum Heave Engine Frost heave is a common environmental process in which the freezing of water into ice can produce forces large enough to seriously damage roads and bridges [1]. Contrary to common belief, frost

Libbrecht, Kenneth G.

357

Frequency Moments Inverse Problem and Maximum (Shannon vs. R enyi-Tsallis) Entropy  

E-Print Network [OSTI]

) maximization of Shannon's entropy (MaxEnt), b) maximization of R#19;enyi-Tsallis entropy (maxTent). ConcerningEnt 4 1.2 Aims 5 2 Frequency moment constraints 5 2.1 Characteristics of MaxEnt choice 6 2.2 Maximum RFrequency Moments Inverse Problem and Maximum (Shannon vs. R#19;enyi-Tsallis) Entropy #3; A case

358

How Is the Maximum Entropy of a Quantized Surface Related to Its Area?  

E-Print Network [OSTI]

The maximum entropy of a quantized surface is demonstrated to be proportional to the surface area in the classical limit. The result is valid in loop quantum gravity, and in a somewhat more general class of approaches to surface quantization. The maximum entropy is calculated explicitly for some specific cases.

I. B. Khriplovich; R. V. Korkin

2001-12-27T23:59:59.000Z

359

Maximum Theoretical Efficiency Limit of Photovoltaic Devices: Effect of Band Structure on Excited State Entropy  

E-Print Network [OSTI]

, we show that the maximum conversion efficiency is limited further by the excited state entropyMaximum Theoretical Efficiency Limit of Photovoltaic Devices: Effect of Band Structure on Excited State Entropy Frank E. Osterloh* Department of Chemistry, University of CaliforniaDavis, One Shields

Osterloh, Frank

360

Feed gas contaminant removal in ion transport membrane systems  

SciTech Connect (OSTI)

An oxygen ion transport membrane process wherein a heated oxygen-containing gas having one or more contaminants is contacted with a reactive solid material to remove the one or more contaminants. The reactive solid material is provided as a deposit on a support. The one or more contaminant compounds in the heated oxygen-containing gas react with the reactive solid material. The contaminant-depleted oxygen-containing gas is contacted with a membrane, and oxygen is transported through the membrane to provide transported oxygen.

Underwood, Richard Paul (Allentown, PA); Makitka, III, Alexander (Hatfield, PA); Carolan, Michael Francis (Allentown, PA)

2012-04-03T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Comments on cathode contaminants and the LBNL test stand  

E-Print Network [OSTI]

LBNL-61978 Comments oncathode contaminants and the LBNL test stand F. Bieniosek,the process of operating the LBNL DARHT cathode test stand.

Bieniosek, F.; Baca, D.; Greenway, W.; Leitner, M.; Kwan, J.W.

2006-01-01T23:59:59.000Z

362

Microscopic Reactive Diffusion of Uranium in the Contaminated...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

States. Abstract: Microscopic and spectroscopic analysis of uranium-contaminated sediment cores beneath the BX waste tank farm at the US Department of Energy (DOE) Hanford...

363

actinide contaminants potential: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Asit 150 There are many locations throughout the world where sub-surface contamination impacts the natural environment, with Geosciences Websites Summary: There are many locations...

364

Method and apparatus for destroying organic contaminants in aqueous liquids  

DOE Patents [OSTI]

A method and apparatus for destroying organic contaminants, such as trichloroethylene, in aqueous liquids, such as groundwater, utilizing steam stripping integrated with biodegradation. The contaminated aqueous liquid is fed into a steam stripper causing the volatilization of essentially all of the organic contaminants and a portion of the aqueous liquid. The majority of the aqueous liquid is discharged from the steam stripper. The volatilized vapors are then condensed to the liquid phase and introduced into a bioreactor. The bioreactor contains methanotrophic microorganisms which convert the organic contaminants into mainly carbon dioxide. The effluent from the bioreactor is then recycled back to the steam stripper for further processing. 2 figures.

Donaldson, T.L.; Wilson, J.H.

1993-09-21T23:59:59.000Z

365

Zebra mussel-directed foodchain transfer of environmental contaminants  

SciTech Connect (OSTI)

Zebra mussel densities in some near-shore areas of Lake Erie exceed 500,000 individuals m{sup 3}. Because of their large biomass, the zebra mussels can collectively filter the entire volume of Lake Erie`s western basin in approximately 7 days. In so doing, the mussels remove a significant fraction of suspended particles, including algae and sediment. If those particles are contaminated with PCBs, the mussels could potentially redirect contaminant cycling in Lake Erie. Their data show that contaminated particles are a significant source of contaminants for the zebra mussel with sediment being more significant source than algae. When particles are the source of contamination for the zebra mussel, significant foodchain contamination may result from direct consumption of contaminated mussels or via an indirect route in which unassimilated contaminants are shunted into zebra mussel feces and the latter are consumed by benthic invertebrates. Trophic transfer of PCBs from zebra mussel feces to gammarids was measured. Importantly, biomagnification of some PCB congeners occurred during foodchain transfer from particles to mussels to feces such that the indirect route of transfer through ingestion of contaminated feces is more significant ecologically. Implications for Lake Erie foodchains will be discussed.

Fisher, S.W.; Bruner, K.A. [Ohio State Univ., Columbus, OH (United States); Landrum, P.F. [Great Lakes Environmental Research Lab., Ann Arbor, MI (United States)

1994-12-31T23:59:59.000Z

366

Controls on arsenic mobility in contaminated wetland and riverbed streams  

E-Print Network [OSTI]

Arsenic mobility and transport in the environment are strongly influenced by associations with solid phases. This dissertation investigates the mechanisms affecting arsenic retention in contaminated wetland and riverbed ...

Keon, Nicole E. (Nicole Elise), 1974-

2002-01-01T23:59:59.000Z

367

The Simulation of Nuclear Contaminant Transport in Fractally ...  

E-Print Network [OSTI]

The presentation will begin with a derivation of a model of nuclear contaminant transport in naturally-fractured porous media. Then, a Locally-Conservative ...

368

The Transport of Nuclear Contamination in Fractured Porous Media ...  

E-Print Network [OSTI]

Nov 2, 2000 ... of the transport and dispersion of nuclear contamination through a granitic ... Many nuclear waste facilities are expected to be located in such.

2000-11-02T23:59:59.000Z

369

C l x C l x contaminant concentrations  

E-Print Network [OSTI]

dioxins 41 legacy Pesticides (dieldrin, ddt, and chlordane) 47 summary Points 49 references 51 contaminants in sport fish, such as dioxins and organochlorine pesticides, the advice is driven

370

Submitted to Risk Management of Contaminated Sediments -International Workshop  

E-Print Network [OSTI]

, Venice International University, Island of San Servolo, Venice, Italy Contaminated Sediments) and the U.S. Department of Energy's Brookhaven National Laboratory (BNL) has been investigating

Brookhaven National Laboratory

371

RESRAD Computer Code- Evaluation of Radioactively Contaminated Sites  

Broader source: Energy.gov [DOE]

The evaluation of sites with radioactive contamination was a problem until the RESidual RADioactivity (RESRAD) Computer Code was first released in 1989.

372

HIGH TEMPERATURE CONDUCTIVITY PROBE FOR MONITORING CONTAMINATION LEVELS IN POWER PLANT BOILER WATER.  

E-Print Network [OSTI]

??A high temperature/high pressure flow through probe was designed to measure high temperature electrical conductivity of aqueous (aq) dilute electrolyte solutions, an application which can… (more)

Hipple, Sarah

2008-01-01T23:59:59.000Z

373

Contaminant levels and source strengths in U.S. retail stores A pilot study  

E-Print Network [OSTI]

, acetaldehyde, and acrolein are three compounds with concentrations above health guidelines in some stores

374

Contaminant levels and source strengths in U.S. retail stores A pilot study  

E-Print Network [OSTI]

Formaldehyde, acetaldehyde, and acrolein are three compoundsincluding formaldehyde and acrolein that were sampled usinghydrazone. In addition, we collected acrolein samples using

Chan, Wanyu Rengie

2013-01-01T23:59:59.000Z

375

Effect of a Rainfall Event on Contaminant Levels in the Brunette River Watershed  

E-Print Network [OSTI]

collected during a rainfall event. Dioxins, furans, polychlorinated biphenyls (PCBs), pesticides objectives for the protection of aquatic life: dioxins/furans, benzo(a)pyrene, DDT, PCBs, trace metals and p'un épisode de pluie. On a mesuré les dioxines, les furanes, les biphényles polychlorés (PCB), les pesticides

376

Characterization of Contaminant Levels in the P-Area Wetland System | SREL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to User Group and User ExecutiveCentralDepartment ofResearch

377

Unification of Field Theory and Maximum Entropy Methods for Learning Probability Densities  

E-Print Network [OSTI]

Bayesian field theory and maximum entropy are two methods for learning smooth probability distributions (a.k.a. probability densities) from finite sampled data. Both methods were inspired by statistical physics, but the relationship between them has remained unclear. Here I show that Bayesian field theory subsumes maximum entropy density estimation. In particular, the most common maximum entropy methods are shown to be limiting cases of Bayesian inference using field theory priors that impose no boundary conditions on candidate densities. This unification provides a natural way to test the validity of the maximum entropy assumption on one's data. It also provides a better-fitting nonparametric density estimate when the maximum entropy assumption is rejected.

Kinney, Justin B

2014-01-01T23:59:59.000Z

378

RESULTS FOR THE FOURTH QUARTER 2011 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS  

SciTech Connect (OSTI)

The Saltstone Facility is designed and permitted to immobilize and dispose of low-level radioactive and hazardous liquid waste (salt solution) remaining from the processing of radioactive material at the Savannah River Site. Low-level waste (LLW) streams from the Effluent Treatment Project (ETP), H-Canyon, and the decontaminated salt solution product from the Actinide Removal Process/Modular Caustic Side Solvent Extraction (CSSX) Unit (ARP/MCU) process are stored in Tank 50 until the LLW can be transferred to the Saltstone Facility for treatment and disposal. The LLW must meet the specified waste acceptance criteria (WAC) before it is processed into saltstone. The specific chemical and radionuclide contaminants and their respective WAC limits are in the current Saltstone WAC. Waste Solidification Engineering (WSE) requested that Savannah River National Laboratory (SRNL) perform quarterly analysis on saltstone samples. The concentrations of chemical and radionuclide contaminants are measured to ensure the saltstone produced during each quarter is in compliance with the current WAC. This report documents the concentrations of chemical and radionuclide contaminants for the 2011 Fourth Quarter samples collected from Tank 50 on October 12, 2011 and discusses those results in further detail than the previously issued results report.

Bannochie, C.

2012-01-31T23:59:59.000Z

379

Reviews of environmental contamination and toxicology  

SciTech Connect (OSTI)

Review of Environmental Contamination and Toxicology attempts to provide concise, critical reviews of timely advances, philosophy and significant areas of accomplished or needed endeavour in the total field of xenobiotics, in any segment of the environment, as well as toxicological implications. This edition contains a paper 'Health effects of arsenic, fluorine and selenium from indoor burning of Chinese coal, by Liu Guijian, Zheng Liugen, Nurdan S. Duzgoren-Aydin, Gao Lianfen, Liu Junhua, and Peng Zicheng. Other papers are: Chemistry and fate of simazine; Ethanol production: energy, economic, and environmental losses; Arsenic behaviour from groundwater and soil to crops: impacts on agriculture and food safety; Mercury content of hair in different populations relative to fish consumption; and Toxicology of 1,3-butadiene, chloroprene, and isoprene. 15 ills.

Ware, G. (ed.)

2007-07-01T23:59:59.000Z

380

Tanpopo cosmic dust collector: Silica aerogel production and bacterial DNA contamination analysis  

E-Print Network [OSTI]

Hydrophobic silica aerogels with ultra-low densities have been designed and developed as cosmic dust capture media for the Tanpopo mission which is proposed to be carried out on the International Space Station. Glass particles as a simulated cosmic dust with 30 \\mu m in diameter and 2.4 g/cm^3 in density were successfully captured by the novel aerogel at a velocity of 6 km/s. Background levels of contaminated DNA in the ultra-low density aerogel were lower than the detection limit of a polymerase chain reaction assay. These results show that the manufactured aerogel has good performance as a cosmic dust collector and sufficient quality in respect of DNA contamination. The aerogel is feasible for the biological analyses of captured cosmic dust particles in the astrobiological studies.

Tabata, Makoto; Yokobori, Shin-ichi; Kawai, Hideyuki; Takahashi, Jun-ichi; Yano, Hajime; Yamagishi, Akihiko

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Physical countermeasures to sustain acceptable living and working conditions in radioactively contaminated residential areas  

E-Print Network [OSTI]

The Chernobyl accident highlighted the need in nuclear preparedness for robust, effective and sustainable countermeasure strategies for restoration of radioactively contaminated residential areas. Under the EC-supporter STRATEGY project a series of investigations were made of countermeasures that were deemed potentially applicable for implementation in such events in European Member States. The findings are presented in this report, in a standardised data sheet format to clarify the features of the individual methods and facilitate intercomparison. The aspects of averted doses and management of wastes generated by countermeasures had to be described separately to provide room for the required level of detail. The information is mainly intended as a tool for decision makers and planners and constitutes of basis for the STRATEGY decision framework for remediation of contaminated urban areas. (au)

Andersson, K G; Roed, J

2003-01-01T23:59:59.000Z

382

Hospital ventilation standards and energy conservation: chemical contamination of hospital air. Final report  

SciTech Connect (OSTI)

In an era of increasing energy conservation consciousness, a critical reassessment of the validity of hospital ventilation and thermal standards is made. If current standards are found to be excessively conservative, major energy conservation measures could be undertaken by rebalancing and/or modification of current HVAC systems. To establish whether or not reducing ventilation rates would increase airborne chemical contamination to unacceptable levels, a field survey was conducted to develop an inventory and dosage estimates of hospital generated airborne chemical contaminants to which patients, staff, and visitors are exposed. The results of the study are presented. Emphasis is on patient exposure, but an examination of occupational exposure was also made. An in-depth assessment of the laboratory air environment is documented. Housekeeping products used in survey hospitals, hazardous properties of housekeeping chemicals and probable product composition are discussed in the appendices.

Rainer, D.; Michaelsen, G.S.

1980-03-01T23:59:59.000Z

383

Summary - Mitigation and Remediation of Mercury Contamination...  

Office of Environmental Management (EM)

and surface water Hg remediation strategy for adequacy in reducing Hg levels in the fish and to indentify opportunities to achieve cost and technical improvements andor to...

384

Enforcement Guidance Supplement 00-01: Enforcement Position Relative to the Discovery/Control of Legacy Contamination  

Broader source: Energy.gov [DOE]

Section 1.3 of the Operational Procedures for Enforcement, published in June 1998, provides the opportunity for the Office of Enforcement and Investigation (EH-Enforcement) to periodically issue clarifying guidance regarding the processes used in its enforcement activities. On November 24, 1999, I issued a memorandum providing interim clarification on the EH-Enforcement position on legacy radioactive contamination. That memorandum was issued in response to questions I had received regarding 10 CFR 835 (Occupational Radiation Protection) applicability and potential enforcement related to the discovery of legacy contamination in unposted and/or uncontrolled areas. This Enforcement Guidance Supplement (EGS) provides more detail related to specific 10 CFR 835 requirements and applicability of those requirements. This EGS also discusses EH-Enforcement's planned level of enforcement discretion associated with legacy contamination incidents, as well as the limitations to the application of that discretion.

385

Enforcement Guidance Supplement 00-01: Enforcement Position Relative to the Discovery/Control of Legacy Contamination  

Broader source: Energy.gov [DOE]

Section 1.3 of the Operational Procedures for Enforcement, published in June 1998, provides the opportunity for the Office of Enforcement and Investigation (EH-Enforcement) to periodically issue clarifying guidance regarding the processes used in its enforcement activities. On November 24, 1999, I issued a memorandum providing interim clarification on the EH-Enforcement position on legacy radioactive contamination. That memorandum was issued in response to questions I had received regarding 10 CFR 835 (Occupational Radiation Protection) applicability and potential enforcement related to the discovery of legacy contamination in unposted and/or uncontrolled areas. This Enforcement Guidance Supplement (EGS) provides more detail related to specific 10 CFR 835 requirements and applicability of those requirements. This EGS also discusses EH-Enforcement’s planned level of enforcement discretion associated with legacy contamination incidents, as well as the limitations to the application of that discretion.

386

Explosive Contamination from Substrate Surfaces: Differences and Similarities in Contamination Techniques using RDX and C-4  

SciTech Connect (OSTI)

The amount of time that an explosive is present on the surface of a material is dependent upon the original amount of explosive on the surface, temperature, humidity, rain, etc. This laboratory study focused on looking at similarities and differences in three different surface contamination techniques that are used when performance testing explosive trace detection equipment in an attempt to determine how effective the techniques are at replicating actual field samples. The three techniques used were dry transfer deposition of solutions using the Transportation Security Laboratory (TSL) patented dry transfer techniques (US patent 6470730), direct deposition of explosive standards, and fingerprinting of actual explosives. Explosives were deposited on the surface of one of five substrates using one of the three different deposition techniques. The process was repeated for each surface type using each contamination technique. The surface types used were: 50% cotton/50% polyester as found in T-shirts, 100% cotton with a smooth surface such as that found in a cotton dress shirt, 100% cotton on a rough surface such as that found on canvas or denim, suede leather such as might be found on jackets, purses, or shoes, and metal obtained from a car hood at a junk yard. The samples were not pre-cleaned prior to testing and contained sizing agents, and in the case of the metal, oil and dirt. The substrates were photographed using a Zeiss Discover V12 stereoscope with Axiocam ICc1 3 megapixel digital camera to determine the difference in the crystalline structure and surface contamination in an attempt to determine differences and similarities associated with current contamination techniques.

C.J. Miller; T.S. Yoder

2010-06-01T23:59:59.000Z

387

High level waste characterization in support of low level waste certification. I. HLW supernate radionuclide characterization  

SciTech Connect (OSTI)

High Level Waste Programs has radioactive waste storage, treatment and processing facilities that are located in the F and H Areas at the Savannah River Site. These facilities include the Effluent Treatment Facility (ETF), F and H Area Tank Farms, Extended Sludge Processing (ESP), and In-Tank Precipitation (ITP). Job wastes are generated from operation, maintenance, and construction activities inside radiological areas. These items may have been contaminated with radioactive supernate, salt, and sludge material. Most of these wastes will be disposed of in the E-area Vaults. Therefore, an isotopic and hazardous characterization must be performed. The characterization of HLW supernate radionuclides is discussed in Chapter I. The characterization for salt and sludge phases, which can also contaminate LLW, will be included in other Chapters.

Jamison, M.E.; d`Entremont, P.D.; Clemmons, J.S.; Bess, C.E.; Brown, D.F.

1994-07-08T23:59:59.000Z

388

Measurement of biodegradation rate constants of a water extract from petroleum-contaminated soil  

SciTech Connect (OSTI)

The study of biodegradation rate constants of petroleum products in water extract from contaminated soil presents an important component in the evaluation of bioremediation process. In this study, soil samples were gathered from an industrial site which was used for maintenance and storage of heavy equipment used in the oil and gas exploration and production industry. The petroleum contaminants were extracted from the soil using distilled water. This water extract was used as the substrate to acclimate a microbial community and also for the biological kinetic studies. Kinetic studies were carried out in batch reactors, and the biodegradation rates were monitored by a computer-controlled respirometer. The BOD data were analyzed by using the Monod equation. Experimental results give the average value of the maximum rate constant as 0.038 mg BOD/(mg VSS hr) and the average value of the substrate concentration of half rate as 746 mg BOD/l. A GC/MS analysis on the sample of the test solutions before and after 5 days of biological oxidation indicates that the hydrocarbons initially present in the solution were degraded.

Li, K.Y.; Kane, A.J.; Wang, J.J.; Cawley, W.A. (Lamar Univ., Beaumont, TX (United States). Chemical Engineering Dept.)

1993-01-01T23:59:59.000Z

389

Contamination effects on fixed-bias Langmuir probes  

SciTech Connect (OSTI)

Langmuir probes are standard instruments for plasma density measurements on many sounding rockets. These probes can be operated in swept-bias as well as in fixed-bias modes. In swept-bias Langmuir probes, contamination effects are frequently visible as a hysteresis between consecutive up and down voltage ramps. This hysteresis, if not corrected, leads to poorly determined plasma densities and temperatures. With a properly chosen sweep function, the contamination parameters can be determined from the measurements and correct plasma parameters can then be determined. In this paper, we study the contamination effects on fixed-bias Langmuir probes, where no hysteresis type effect is seen in the data. Even though the contamination is not evident from the measurements, it does affect the plasma density fluctuation spectrum as measured by the fixed-bias Langmuir probe. We model the contamination as a simple resistor-capacitor circuit between the probe surface and the plasma. We find that measurements of small scale plasma fluctuations (meter to sub-meter scale) along a rocket trajectory are not affected, but the measured amplitude of large scale plasma density variation (tens of meters or larger) is attenuated. From the model calculations, we determine amplitude and cross-over frequency of the contamination effect on fixed-bias probes for different contamination parameters. The model results also show that a fixed bias probe operating in the ion-saturation region is affected less by contamination as compared to a fixed bias probe operating in the electron saturation region.

Steigies, C. T. [Institut fuer Experimentelle und Angewandte Physik, Christian-Albrechts-Universitaet zu Kiel, 24098 Kiel (Germany); Barjatya, A. [Department of Physical Sciences, Embry-Riddle Aeronautical University, Daytona Beach, Florida 32114 (United States)

2012-11-15T23:59:59.000Z

390

IN SITU REMEDIATION OF CONTAMINATED SEDIMENTS - ACTIVE CAPPING TECHNOLOGY  

SciTech Connect (OSTI)

Active capping is a relatively new approach for treating contaminated sediments. It involves applying chemically reactive amendments to the sediment surface. The main role of active caps is to stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column. Metals are common contaminants in many marine and fresh water environments as a result of industrial and military activities. The mobile, soluble forms of metals are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This approach can be achieved through application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active capping technology. Active capping holds great potential for a more permanent solution that avoids residual risks resulting from contaminant migration through the cap or breaching of the cap. In addition to identifying superior active capping agents, research is needed to optimize application techniques, application rates, and amendment combinations that maximize sequestration of contaminants. A selected set of active capping treatment technologies has been demonstrated at a few sites, including a field demonstration at the Savannah River Site, Aiken, SC. This demonstration has provided useful information on the effects of sequestering agents on metal immobilization, bioavailability, toxicity, and resistance to mechanical disturbance.

Knox, A.; Roberts, J.; Paller, M.; Reible, D.

2010-09-02T23:59:59.000Z

391

Remediation of arsenic-contaminated soils and groundwaters  

DOE Patents [OSTI]

An in situ method for extraction of arsenic contaminants from a soil medium and remediation of the medium including contacting the medium with an extractant solution, directing the solution within and through the medium, and collecting the solution and contaminants. The method can also be used for arsenate and/or arsenite removal.

Peters, Robert W. (Naperville, IL); Frank, James R. (Glen Ellyn, IL); Feng, Xiandong (West Richland, WA)

1998-01-01T23:59:59.000Z

392

Method for treatment of soils contaminated with organic pollutants  

DOE Patents [OSTI]

A method for treating soil contaminated by organic compounds wherein an ozone containing gas is treated with acid to increase the stability of the ozone in the soil environment and the treated ozone applied to the contaminated soil to decompose the organic compounds. The soil may be treated in situ or may be removed for treatment and refilled.

Wickramanayake, Godage B. (Cranbury, NJ)

1993-01-01T23:59:59.000Z

393

Microbial Janitors: Enabling natural microbes to clean up uranium contamination  

E-Print Network [OSTI]

Microbial Janitors: Enabling natural microbes to clean up uranium contamination Oak Ridge to the development of the atomic bomb. Uranium enrichment activities on the Oak Ridge Reservation in the 1940s until then the uranium and nitrate contamination has spread through the ground and now covers an area of about 7 km

394

Capture zone design for a contaminated shallow unconfined aquifer  

E-Print Network [OSTI]

from the early 1950's to 1987. The extent of the ground water contamination has impacted City of Austin properties, private residential areas, and is migrating towards the Colorado River to the South. A capture zone is proposed to stop the contaminants...

Cann, Eric Roy

2012-06-07T23:59:59.000Z

395

CONSTRUCTION-GRADE CEMENT PRODUCTION FROM CONTAMINATED SEDIMENTS USING  

E-Print Network [OSTI]

1 CONSTRUCTION-GRADE CEMENT PRODUCTION FROM CONTAMINATED SEDIMENTS USING CEMENT-LOCKTM TECHNOLOGY A manufacturing technology for producing construction-grade cements from a wide variety of contaminated waste cementitious properties that allow it to be transformed into construction-grade cement. The Cement

Brookhaven National Laboratory

396

Activated Peroxygens for Remediation of Contaminated Soil and Groundwater  

E-Print Network [OSTI]

i Activated Peroxygens for Remediation of Contaminated Soil and Groundwater Ph.D. thesis Submitted of Doctor of Philosophy Department of Chemistry, Biotechnology and Environmental Engineering Section May 2011 #12;ii Activated Peroxygens for Remediation of Contaminated Soil and Groundwater Ph.D. thesis

Hansen, René Rydhof

397

ORIGINAL PAPER Bioremediation of oily sludge-contaminated soil  

E-Print Network [OSTI]

ORIGINAL PAPER Bioremediation of oily sludge-contaminated soil by stimulating indigenous microbes In situ bioremediation of oily sludge- contaminated soil by biostimulation of indigenous microbes through. Keywords Bioremediation Á Biostimulation Á In situ Á Microbial community Á Oily sludge Introduction

Ma, Lena

398

Contaminant Concentrations in Fish SacramentoSan Joaquin Delta  

E-Print Network [OSTI]

of Fish and Game) arranged for age determination of largemouth bass. Henry Lee (U.S. EPA) reviewed a draftContaminant Concentrations in Fish from the Sacramento­San Joaquin Delta and Lower San Joaquin ......................................................................................... 45 Contaminant Concentrations in Fish from the Sacramento­San Joaquin Delta and Lower San Joaquin

399

Electron Microbeam Investigation of Uranium-Contaminated Soils from  

E-Print Network [OSTI]

Research Electron Microbeam Investigation of Uranium-Contaminated Soils from Oak Ridge, TN, USA J O Street, Baltimore, Maryland 21218, Department of Geological Sciences, Indiana University, 1001 East 10th Street, Bloomington, Indiana 47405 Two samples of uranium-contaminated soil from the Department of Energy

Zhu, Chen

400

Radioactive contamination of SrI2(Eu) crystal scintillator  

E-Print Network [OSTI]

A strontium iodide crystal doped by europium (SrI2(Eu)) was produced by using the Stockbarger growth technique. The crystal was subjected to characterisation that included relative photoelectron output and energy resolution for gamma quanta. The intrinsic radioactivity of SrI2(Eu) crystal scintillator was tested both in scintillation mode and by using ultra-low background HPGe gamma spectrometry deep underground. The response of the SrI2(Eu) detector to alpha particles (alpha/beta ratio and pulse shape) was estimated by analysing the 226Ra trace contamination internal to the crystal. We have found alpha/beta=0.55 and no difference in scintillation decay for alpha particles and gamma quanta. The application of the obtained results in the search for the double electron capture and electron capture with positron emission in 84Sr has been investigated at a level of sensitivity T_1/2 \\sim 10^15-10^16 yr. The results of these studies demonstrate the potentiality of this material for a variety of scintillation appli...

Belli, P; Cerulli, R; Danevich, F A; Galenin, E; Gektin, A; Incicchitti, A; Isaienko, V; Kobychev, V V; Laubenstein, M; Nagorny, S S; Podviyanuk, R B; Tkachenko, S; Tretyak, V I

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Method for detecting organic contaminants in water supplies  

DOE Patents [OSTI]

A system is described for detecting organic contaminants in water supplies. A sampling unit is employed which includes a housing having at least one opening therein and a tubular member positioned within the housing having a central passageway surrounded by a side wall. The side wall is made of a composition designed to absorb the contaminants. In use, the sampling unit is immersed in a water supply. The water supply contacts the tubular member through the opening in the housing, with any contaminants being absorbed into the side wall of the tubular member. A carrier gas is then passed through the central passageway of the tubular member. The contaminants will diffuse out of the side wall and into the central passageway where they will subsequently combine with the carrier gas, thereby yielding a gaseous product. The gaseous product is then analyzed to determine the amount and type of contaminants therein. 5 figs.

Dooley, K.J.; Barrie, S.L.; Buttner, W.J.

1999-08-24T23:59:59.000Z

402

Methods for removing contaminant matter from a porous material  

DOE Patents [OSTI]

Methods of removing contaminant matter from porous materials include applying a polymer material to a contaminated surface, irradiating the contaminated surface to cause redistribution of contaminant matter, and removing at least a portion of the polymer material from the surface. Systems for decontaminating a contaminated structure comprising porous material include a radiation device configured to emit electromagnetic radiation toward a surface of a structure, and at least one spray device configured to apply a capture material onto the surface of the structure. Polymer materials that can be used in such methods and systems include polyphosphazine-based polymer materials having polyphosphazine backbone segments and side chain groups that include selected functional groups. The selected functional groups may include iminos, oximes, carboxylates, sulfonates, .beta.-diketones, phosphine sulfides, phosphates, phosphites, phosphonates, phosphinates, phosphine oxides, monothio phosphinic acids, and dithio phosphinic acids.

Fox, Robert V. (Idaho Falls, ID) [Idaho Falls, ID; Avci, Recep (Bozeman, MT) [Bozeman, MT; Groenewold, Gary S. (Idaho Falls, ID) [Idaho Falls, ID

2010-11-16T23:59:59.000Z

403

Method for detecting organic contaminants in water supplies  

DOE Patents [OSTI]

A system for detecting organic contaminants in water supplies. A sampling unit is employed which includes a housing having at least one opening therein and a tubular member positioned within the housing having a central passageway surrounded by a side wall. The side wall is made of a composition designed to absorb the contaminants. In use, the sampling unit is immersed in a water supply. The water supply contacts the tubular member through the opening in the housing, with any contaminants being absorbed into the side wall of the tubular member. A carrier gas is then passed through the central passageway of the tubular member. The contaminants will diffuse out of the side wall and into the central passageway where they will subsequently combine with the carrier gas, thereby yielding a gaseous product. The gaseous product is then analyzed to determine the amount and type of contaminants therein.

Dooley, Kirk J. (Shelley, ID); Barrie, Scott L. (Idaho Falls, ID); Buttner, William J. (White Bear Lake, MN)

1999-01-01T23:59:59.000Z

404

Use of Source Term and Air Dispersion Modeling in Planning Demolition of Highly Alpha-Contaminated Buildings  

SciTech Connect (OSTI)

The current cleanup of structures related to cold-war production of nuclear materials includes the need to demolish a number of highly alpha-contaminated structures. The process of planning for the demolition of such structures includes unique challenges related to ensuring the protection of both workers and the public. Pre-demolition modeling analyses were conducted to evaluate potential exposures resulting from the proposed demolition of a number of these structures. Estimated emission rates of transuranic materials during demolition are used as input to an air-dispersion model. The climatological frequencies of occurrence of peak air and surface exposures at locations of interest are estimated based on years of hourly meteorological records. The modeling results indicate that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. The pre-demolition modeling directed the need for better contamination characterization and/or different demolition methods—and in the end, provided a basis for proceeding with the planned demolition activities. Post-demolition modeling was also conducted for several contaminated structures, based on the actual demolition schedule and conditions. Comparisons of modeled and monitoring results are shown. Recent monitoring data from the demolition of a UO3 plant shows increments in concentrations that were previously identified in the pre-demolition modeling predictions; these comparisons confirm the validity and value of the pre-demolition source-term and air dispersion computations for planning demolition activities for other buildings with high levels of radioactive contamination.

Droppo, James G.; Napier, Bruce A.; Rishel, Jeremy P.; Bloom, Richard W.

2011-06-22T23:59:59.000Z

405

Position-sensitive radiation monitoring (surface contamination monitor). Innovative technology summary report  

SciTech Connect (OSTI)

The Shonka Research Associates, Inc. Position-Sensitive Radiation Monitor both detects surface radiation and prepares electronic survey map/survey report of surveyed area automatically. The electronically recorded map can be downloaded to a personal computer for review and a map/report can be generated for inclusion in work packages. Switching from beta-gamma detection to alpha detection is relatively simple and entails moving a switch position to alpha and adjusting the voltage level to an alpha detection level. No field calibration is required when switching from beta-gamma to alpha detection. The system can be used for free-release surveys because it meets the federal detection level sensitivity limits requires for surface survey instrumentation. This technology is superior to traditionally-used floor contamination monitor (FCM) and hand-held survey instrumentation because it can precisely register locations of radioactivity and accurately correlate contamination levels to specific locations. Additionally, it can collect and store continuous radiological data in database format, which can be used to produce real-time imagery as well as automated graphics of survey data. Its flexible design can accommodate a variety of detectors. The cost of the innovative technology is 13% to 57% lower than traditional methods. This technology is suited for radiological surveys of flat surfaces at US Department of Energy (DOE) nuclear facility decontamination and decommissioning (D and D) sites or similar public or commercial sites.

Not Available

1999-06-01T23:59:59.000Z

406

Task 15 -- Remediation of organically contaminated soil using hot/liquid (subcritical) water. Semi-annual report, April 1--September 30, 1997  

SciTech Connect (OSTI)

This activity involves a pilot-scale demonstration of the use of hot/liquid water for the removal of organic contaminants from soil at the pilot (20 to 40 kg) scale. Lab-scale studies are being performed to determine the optimum temperature, contact time, and flow rates for removal of the organic contaminants. Initial investigations into using carbon sorbents to clean the extractant water for recycle use and to concentrate the extracted contaminants in a small volume for disposal are also being performed. Liquid water is normally considered to be too polar a solvent to be effective for removal of organic contaminants from contaminated soils and sludges. However, the Energy and Environmental Research Center (EERC) has demonstrated that the polarity of liquid water can be changed from that of a very polar solvent at ambient conditions to that of an organic solvent (e.g., ethanol or acetonitrile) by simply raising the temperature. The EERC has exploited this unique property of liquid water to obtain highly selective extractions of polar (at lower temperatures) to nonpolar (at 200 to 250 C) organics from contaminated soils and sludges. Only moderate pressures (a maximum of about 45 atm at 250 C and lower pressures at lower temperatures) are required. With this procedure, all detectable hazardous organics were removed from the sludge, thus making the remaining material (about 99% of the original mass) a nonhazardous material. The present understanding of hot/liquid water extraction for the removal of hazardous organics from contaminated soils and sludges is being used to develop the engineering parameters needed to perform a pilot-scale demonstration of the remediation technology. Progress during the report period is summarized.

Hawthorne, S.B.

1997-12-31T23:59:59.000Z

407

Microcontroller Servomotor for Maximum Effective Power Point for Solar Cell System  

E-Print Network [OSTI]

In this paper a Maximum Power point (MPP) tracking algorithm is developed using dual-axis servomotor feedback tracking control system. An efficient and accurate servomotor system is used to increase the system efficiency and reduces the solar cell...

Al-Khalidy, M.; Al-Rawi, O.; Noaman, N.

2010-01-01T23:59:59.000Z

408

Achieving Consistent Maximum Brake Torque with Varied Injection Timing in a DI Diesel Engine  

E-Print Network [OSTI]

, the characteristics of combustion for swept injection timings along the maximum brake torque plateau are determined. The research is conducted by varying injection timing at constant engine speed and load while measuring engine emissions and in-cylinder pressure...

Kroeger, Timothy H

2013-09-19T23:59:59.000Z

409

Delay Analysis of Maximum Weight Scheduling in Wireless Ad Hoc Networks  

E-Print Network [OSTI]

This paper studies delay properties of the well-known maximum weight scheduling algorithm in wireless ad hoc networks. We consider wireless networks with either one-hop or multihop flows. Specifically, this paper shows ...

Modiano, Eytan H.

410

Tropical climate variability from the last glacial maximum to the present  

E-Print Network [OSTI]

This thesis evaluates the nature and magnitude of tropical climate variability from the Last Glacial Maximum to the present. The temporal variability of two specific tropical climate phenomena is examined. The first is the ...

Dahl, Kristina Ariel

2005-01-01T23:59:59.000Z

411

Dynamical Reconstruction of Upper-Ocean Conditions in the Last Glacial Maximum Atlantic  

E-Print Network [OSTI]

Proxies indicate that the Last Glacial Maximum (LGM) Atlantic Ocean was marked by increased meridional and zonal near sea surface temperature gradients relative to today. Using a least squares fit of a full general circulation ...

Wunsch, Carl

412

Atlantic Ocean circulation at the last glacial maximum : inferences from data and models  

E-Print Network [OSTI]

This thesis focuses on ocean circulation and atmospheric forcing in the Atlantic Ocean at the Last Glacial Maximum (LGM, 18-21 thousand years before present). Relative to the pre-industrial climate, LGM atmospheric CO? ...

Dail, Holly Janine

2012-01-01T23:59:59.000Z

413

Submodule Integrated Distributed Maximum Power Point Tracking for Solar Photovoltaic Applications  

E-Print Network [OSTI]

This paper explores the benefits of distributed power electronics in solar photovoltaic applications through the use of submodule integrated maximum power point trackers (MPPT). We propose a system architecture that provides ...

Pilawa-Podgurski, Robert C. N.

414

Acoustic Space Dimensionality Selection and Combination using the Maximum Entropy Principle   

E-Print Network [OSTI]

In this paper we propose a discriminative approach to acoustic space dimensionality selection based on maximum entropy modelling. We form a set of constraints by composing the acoustic space with the space of phone classes, and use a continuous...

Abdel-Haleem, Yasser H; Renals, Steve; Lawrence, Neil D

2004-01-01T23:59:59.000Z

415

Author's personal copy Unified behaviour of maximum soot yields of methane, ethane and propane  

E-Print Network [OSTI]

Author's personal copy Unified behaviour of maximum soot yields of methane, ethane and propane the current study and the previous measurements in similar flames with methane, ethane, and propane flames

Gülder, �mer L.

416

Treatment of Mercury Contaminated Oil from Sandia National Laboratory  

SciTech Connect (OSTI)

First Article Tests of a stabilization method for greater than 260 mg mercury/kg oil were performed under a treatability study. This alternative treatment technology will address treatment of U.S. Department of Energy (DOE) organics (mainly used pump oil) contaminated with mercury and other heavy metals. Some of the oil is also co-contaminated with tritium, other radionuclides, and hazardous materials. The technology is based on contacting the oil with a sorbent powder (Self-Assembled Mercaptan on Mesoporous Support, SAMMS), proven to adsorb heavy metals, followed by stabilization of the oil/powder mixture using a stabilization agent (Nochar N990). Two variations of the treatment technology were included in the treatability study. The SAMMS (Self-Assembled Mercaptan on Mesoporous Silica) technology was developed by the Pacific Northwest National Laboratory for removal and stabilization of RCRA metals (i.e., lead, mercury, cadmium, silver, etc.) and for removal of mercury from organic solvents [1]. The SAMMS material is based on self-assembly of functionalized monolayers on mesoporous oxide surfaces. The unique mesoporous oxide supports provide a high surface area, thereby enhancing the metal-loading capacity. SAMMS material has high flexibility in that it binds with different forms of mercury, including metallic, inorganic, organic, charged, and neutral compounds [1] The material removes mercury from both organic wastes, such as pump oils, and from aqueous wastes. Mercury-loaded SAMMS not only passes TCLP tests, but also has good long-term durability as a waste form because: (1) the covalent binding between mercury and SAMMS has good resistance in ion-exchange, oxidation, and hydrolysis over a wide pH range and (2) the uniform and small pore size of the mesoporous silica prevents bacteria from solubilizing the bound mercury. Nochar's N990 Petrobond (Nochar, Inc., Indianapolis, IN) is an oil stabilization agent, specifically formulated for stabilizing vacuum pump oil, which has fewer volatile organics than many other oils. This material is a non-uniform granular powder that resembles ground Styrofoam plastics. This material has previously been used by itself and in combination with SAMMS to stabilize oil containing low levels of mercury {approx}50 mg/kg in surrogate waste studies [2].

Klasson, KT

2002-05-28T23:59:59.000Z

417

Draft Level 1 Remedial Investigation Work Plan: 316-3 waste disposal trenches  

SciTech Connect (OSTI)

This work plan describes the work to be performed for the initial level of site characterization for the 316.3 Trenches at the Hanford Site. This initial site characterization effort will include a review of existing environmental contamination data for the 300 Area as well as collection and analysis of environmental samples to better characterize subsurface contamination at the site. 7 refs., 10 figs., 7 tabs.

Not Available

1987-09-01T23:59:59.000Z

418

Radiation levels on empty cylinders containing heel material  

SciTech Connect (OSTI)

Empty UF{sub 6} cylinders containing heel material were found to emit radiation levels in excess of 200 mr/hr, the maximum amount stated in ORO-651. The radiation levels were as high as 335 mr/hr for thick wall (48X and 48Y) cylinders and 1050 mr/hr for thin wall (48G and 48H) cylinders. The high readings were found only on the bottom of the cylinders. These radiation levels exceeded the maximum levels established in DOT 49 CFR, Part 173.441 for shipment of cylinders. Holding periods of four weeks for thick-wall cylinders and ten weeks for thin-wall cylinders were established to allow the radiation levels to decay prior to shipment.

Shockley, C.W. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31T23:59:59.000Z

419

A stochastic model for sediment yield using the Principle of Maximum Entropy  

E-Print Network [OSTI]

WATER RESOURCES RESEARCH, VOL. 23, NO. 5, PAGES 781-793, MAY 1987 A Stochastic Model for Sediment Yield Using the Principle of Maximum Entropy V. P. SINGH AND P. F. KRSTANOVIC Department of Civil Engineering, Louisiana State University, Baton... Rouge The principle of maximum entropy was applied to derive a stochastic model for sediment yield from upland watersheds. By maximizing the conditional entropy subject to certain constraints, a probability distribution of sediment yield conditioned...

Singh, V. P.; Krstanovic, P. F.

420

Heterogeneity-corrected vs -uncorrected critical structure maximum point doses in breast balloon brachytherapy  

SciTech Connect (OSTI)

Recent studies have reported potentially clinically meaningful dose differences when heterogeneity correction is used in breast balloon brachytherapy. In this study, we report on the relationship between heterogeneity-corrected and -uncorrected doses for 2 commonly used plan evaluation metrics: maximum point dose to skin surface and maximum point dose to ribs. Maximum point doses to skin surface and ribs were calculated using TG-43 and Varian Acuros for 20 patients treated with breast balloon brachytherapy. The results were plotted against each other and fit with a zero-intercept line. Max skin dose (Acuros) = max skin dose (TG-43) ? 0.930 (R{sup 2} = 0.995). The average magnitude of difference from this relationship was 1.1% (max 2.8%). Max rib dose (Acuros) = max rib dose (TG-43) ? 0.955 (R{sup 2} = 0.9995). The average magnitude of difference from this relationship was 0.7% (max 1.6%). Heterogeneity-corrected maximum point doses to the skin surface and ribs were proportional to TG-43-calculated doses. The average deviation from proportionality was 1%. The proportional relationship suggests that a different metric other than maximum point dose may be needed to obtain a clinical advantage from heterogeneity correction. Alternatively, if maximum point dose continues to be used in recommended limits while incorporating heterogeneity correction, institutions without this capability may be able to accurately estimate these doses by use of a scaling factor.

Kim, Leonard, E-mail: kimlh@umdnj.edu [Department of Radiation Oncology, Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ (United States); Narra, Venkat; Yue, Ning [Department of Radiation Oncology, Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ (United States)

2013-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

A study of biological contaminants in rainwater collected from rooftops in Bryan and College Station Texas  

E-Print Network [OSTI]

This study was conducted to identify the presence of biological contaminants and the factors responsible for these contaminants in rainwater collected from rooftops of buildings in Bryan and College Station, Texas. Two main biological contaminants...

Vasudevan, Lakshmi Narasimhan

2002-01-01T23:59:59.000Z

422

Factors Affecting Indoor Air Concentrations of Volatile Organic Compounds at a Site of Subsurface Gasoline Contamination  

E-Print Network [OSTI]

AT A SITE OF SUBSURFACE GASOLINE CONTAMINATION Marc L.A T A SITE OF SUBSURFACE GASOLINE CONTAMINATION Marc L.a site contaminated with gasoline. Although the high V O C

Fischer, M.L.

2011-01-01T23:59:59.000Z

423

A Plutonium-Contaminated Wound, 1985, USA  

SciTech Connect (OSTI)

A hand injury occurred at a U.S. facility in 1985 involving a pointed shaft (similar to a meat thermometer) that a worker was using to remove scrap solid plutonium from a plastic bottle. The worker punctured his right index finger on the palm side at the metacarpal-phalangeal joint. The wound was not through-and- through, although it was deep. The puncture wound resulted in deposition of ~48 kBq of alpha activity from the weapons-grade plutonium mixture with a nominal 12 to 1 Pu-alpha to {sup 241}Am-alpha ratio. This case clearly showed that DTPA was very effective for decorporation of plutonium and americium. The case is a model for management of wounds contaminated with transuranics: (1) a team approach for dealing with all of the issues surrounding the incident, including the psychological, (2) early surgical intervention for foreign-body removal, (3) wound irrigation with DTPA solution, and (4) early and prolonged DTPA administration based upon bioassay and in vivo dosimetry.

Doran M. Christensen, DO, REAC /TS Associate Director and Staff Physician Eugene H. Carbaugh, CHP, Staff Scientist, Internal Dosimetry Manager, Pacific Northwest National Laboratory, Richland, Washington

2012-02-02T23:59:59.000Z

424

Assessment of hot gas contaminant control  

SciTech Connect (OSTI)

The objective of this work is to gather data and information to assist DOE in responding to the NRC recommendation on hot gas cleanup by performing a comprehensive assessment of hot gas cleanup systems for advanced coal-based Integrated Gasification Combined Cycle (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) including the status of development of the components of the hot gas cleanup systems, and the probable cost and performance impacts. The scope and time frame of information gathering is generally responsive to the boundaries set by the National Research council (NRC), but includes a broad range of interests and programs which cover hot gas cleanup through the year 2010. As the status of hot gas cleanup is continually changing, additional current data and information are being obtained for this effort from this 1996 METC Contractors` Review Meeting as well as from the 1996 Pittsburgh Coal Conference, and the University of Karlsruhe Symposium. The technical approach to completing this work consists of: (1) Determination of the status of hot gas cleanup technologies-- particulate collection systems, hot gas desulfurization systems, and trace contaminant removal systems; (2) Determination of hot gas cleanup systems cost and performance sensitivities. Analysis of conceptual IGCC and PFBC plant designs with hot gas cleanup have been performed. The impact of variations in hot gas cleanup technologies on cost and performance was evaluated using parametric analysis of the baseline plant designs and performance sensitivity.

Rutkowski, M.D.; Klett, M.G.; Zaharchuk, R.

1996-12-31T23:59:59.000Z

425

California GAMA Program: A Contamination Vulnerability Assessment for the Bakersfield Area  

SciTech Connect (OSTI)

In response to concerns expressed by the California Legislature and the citizenry of the State of California, the State Water Resources Control Board (SWRCB), implemented a program to assess groundwater quality, and provide a predictive capability for identifying areas that are vulnerable to contamination. The program was initiated in response to concern over public supply well closures due to contamination by chemicals such as MTBE from gasoline, and solvents from industrial operations. As a result of this increased awareness regarding groundwater quality, the Supplemental Report of the 1999 Budget Act mandated the SWRCB to develop a comprehensive ambient groundwater-monitoring plan, and led to the initiation of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The primary objective of the GAMA Program is to assess the water quality and to predict the relative susceptibility to contamination of groundwater resources throughout the state of California. Under the GAMA program, scientists from Lawrence Livermore National Laboratory (LLNL) collaborate with the SWRCB, the U.S. Geological Survey (USGS), the California Department of Health Services (DHS), and the California Department of Water Resources (DWR) to implement this groundwater assessment program. In 2003, LLNL carried out this vulnerability study in the groundwater basin that underlies Bakersfield, in the southern San Joaquin Valley. The goal of the study is to provide a probabilistic assessment of the relative vulnerability of groundwater used for the public water supply to contamination from surface sources. This assessment of relative contamination vulnerability is made based on the results of two types of analyses that are not routinely carried out at public water supply wells: ultra low-level measurement of volatile organic compounds (VOCs), and groundwater age dating (using the tritium-helium-3 method). In addition, stable oxygen isotope measurements help determine the recharge water source location. Interpreted together, and in the context of existing water quality and hydrogeologic data, these observable parameters help define the flow field of a groundwater basin, and indicate the degree of vertical communication between near-surface sources (or potential sources) of contamination, and deeper groundwater pumped at high capacity production wells.

Moran, J E; Hudson, G B; Eaton, G F; Leif, R

2004-11-01T23:59:59.000Z

426

RCUT: A Non-Invasive Method for Detection, Location, and Quantification of Radiological Contaminants in Pipes and Ducts - 12514  

SciTech Connect (OSTI)

Radiological Characterization Using Tracers (RCUT) is a minimally invasive method for detection and location of residual radiological contamination in pipes and ducts. The RCUT technology utilizes reactive gaseous tracers that dissociate when exposed to gamma and/or beta radiation emitting from a radiological contaminant in a pipe or duct. Sulfur hexafluoride (SF{sub 6}) was selected as a tracer for this radiological application, because it is a chemically inert gas that is both nonflammable, nontoxic, and breaks down when exposed to gamma radiation. Laboratory tests demonstrated that the tracer pair of SF{sub 6} and O{sub 2} formed SO{sub 2}F{sub 2} when exposed to a gamma or beta radioactive field, which indicated the presence of radiological contamination. Field application of RCUT involves first injecting the reactive tracers into the pipe to fill the pipe being inspected and allowing sufficient time for the tracer to interact with any contaminants present. This is followed by the injection of an inert gas at one end of the pipe to push the reactive tracer at a known or constant flow velocity along the pipe and then out the exit and sampling port at the end of the pipeline where its concentration is measured by a gas chromatograph. If a radiological contaminant is present in the pipe being tested, the presence of SO{sub 2}F{sub 2} will be detected. The time of arrival of the SO{sub 2}F{sub 2} can be used to locate the contaminant. If the pipe is free of radiological contamination, no SO{sub 2}F{sub 2} will be detected. RCUT and PCUT are both effective technologies that can be used to detect contamination within pipelines without the need for mechanical or human inspection. These methods can be used to detect, locate, and/or estimate the volume of a variety of radioactive materials and hazardous chemicals such as chlorinated solvents, petroleum products, and heavy metals. While further optimization is needed for RCUT, the key first step of identification of a tracer compound appropriate for the application of detecting radioactive pipeline contamination through the detection of decomposition products of SF{sub 6} has been demonstrated. Other tracer gases that will also undergo radiolysis will be considered in the future. The next step for the RCUT development process is conducting laboratory scale tests using short pipelines to define analytical requirements, establish performance boundaries, and develop strategies for lower exposure levels. Studies to identify additional analytical techniques using equipment that is more field rugged than a GC/MS would also be beneficial. (authors)

Bratton, Wesley L.; Maresca, Joseph W. Jr.; Beck, Deborah A. [Vista Engineering Technologies, L.L.C., Richland, WA, 99352 (United States)

2012-07-01T23:59:59.000Z

427

Application of molten salt oxidation for the minimization and recovery of plutonium-238 contaminated wastes  

SciTech Connect (OSTI)

This paper presents the technical and economic feasibility of molten salt oxidation technology as a volume reduction and recovery process for {sup 238}Pu contaminated waste. Combustible low-level waste material contaminated with {sup 238}Pu residue is destroyed by oxidation in a 900 C molten salt reaction vessel. The combustible waste is destroyed creating carbon dioxide and steam and a small amount of ash and insoluble {sup 2328}Pu in the spent salt. The valuable {sup 238}Pu is recycled using aqueous recovery techniques. Experimental test results for this technology indicate a plutonium recovery efficiency of 99%. Molten salt oxidation stabilizes the waste converting it to a non-combustible waste. Thus installation and use of molten salt oxidation technology will substantially reduce the volume of {sup 238}Pu contaminated waste. Cost-effectiveness evaluations of molten salt oxidation indicate a significant cost savings when compared to the present plans to package, or re-package, certify and transport these wastes to the Waste Isolation Pilot Plant for permanent disposal. Clear and distinct cost advantages exist for MSO when the monetary value of the recovered {sup 238}Pu is considered.

Wishau, R.; Ramsey, K.B.; Montoya, A.

1998-12-31T23:59:59.000Z

428

Bioavailability of sediment-bound contaminants to marine organisms  

SciTech Connect (OSTI)

The bioavailability of sediment-bound contaminants to marine organisms indicates that there exists a potential for transfer of these contaminants through marine food webs to commercial fisheries products consumed by humans. However, there has been relatively little effort to combine and synthesize data on chemical/biological interactions between benthic animals and seagrasses and the sediments in which they reside on the one hand, and on the chemistry of bioaccumulation on the other. This report provides a conceptual basis for an approach to bioavailability and biomagnification of sediment-bound contaminants that reviews biological and chemical approaches.

Brown, B. [Battelle/Marine Sciences Lab., Sequim, WA (United States); [Colby Coll., Waterville, ME (United States); Neff, J. [Battelle/Marine Sciences Lab., Sequim, WA (United States); [Battelle Ocean Sciences, Duxbury, MA (United States)

1993-09-01T23:59:59.000Z

429

Relationship between the {sup 137}Cs whole-body counting results and soil and food contamination in farms near Chernobyl  

SciTech Connect (OSTI)

The authors measured the radioactivity in the soil and child food samples from farms near Mogilev (56--270 GBq km{sup {minus}2} {sup 137}Cs), Gomel (36--810 GBq km{sup {minus}2} {sup 137}Cs), and Klincy (59--270 GBq km{sup {minus}2} {sup 137}Cs), who had whole-body {sup 137}Cs counting results measured as part of a health examination in the Chernobyl Sasakawa Health and Medical Cooperation Project. Soil contamination on the family farm seems to be the main source of human contamination because most of the people in the area live on small farms and they and their domestic animals eat crops from the farms. A clear correlation was found between the children's whole-body {sup 137}Cs counting results and the radioactivity in their food (correlation coefficient: 0.76; confidence level of correlation: 3.2 x 10{sup {minus}9}). There were also significant correlations between the whole-body {sup 137}Cs counting results and both the radioactivity of the soil samples (correlation coefficient: 0.22; confidence level of correlation: 0.0107) and the average contamination level of their current residence (correlation coefficient: 0.20; confidence level of correlation: 0.0174).

Takatsuji, Toshihiro; Sato, Hitoshi; Takada, Jun [and others] [and others

2000-01-01T23:59:59.000Z

430

Effect of Coal Gas Contaminants on Solid Oxide Fuel Cell Operation...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Coal Gas Contaminants on Solid Oxide Fuel Cell Operation. Effect of Coal Gas Contaminants on Solid Oxide Fuel Cell Operation. Abstract: The operation of solid oxide fuel cells...

431

E-Print Network 3.0 - alpha contaminated wastes Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and solid radioactively contaminated wastes in unlined... that uses electrical power to heat and melt contaminated soil, fusing the ... Source: Pint, Bruce A. - Materials...

432

On the "viscosity maximum" during the uniaxial extension of a low density polyethylene  

E-Print Network [OSTI]

An experimental investigation of the viscosity overshoot phenomenon observed during uniaxial extension of a low density polyethylene is pre- sented. For this purpose, traditional integral viscosity measurements on a Muenstedt type extensional rheometer are combined with local mea- surements based on the in-situ visualization of the sample under exten- sion. For elongational experiments at constant strain rates within a wide range of Weissenberg numbers (Wi), three distinct deformation regimes are identified. Corresponding to low values of Wi (regime I), the tensile stress displays a broad maximum. This maximum can be explained by simple mathematical arguments as a result of low deformation rates and it should not be confused with the viscosity overshoot phenomenon. Corre- sponding to intermediate values of Wi (regime II), a local maximum of the integral extensional viscosity is systematically observed. However, within this regime, the local viscosity measurements reveal no maximum, but a plateau. Careful inspection of the images of samples within this regime shows that, corresponding to the maximum of the integral viscosity, sec- ondary necks develop along the sample. The emergence of a maximum of the integral elongational viscosity is thus related to the distinct in- homogeneity of deformation states and is not related to the rheological properties of the material. In the fast stretching limit (high Wi, regime III), the overall geometric uniformity of the sample is well preserved, no secondary necks are observed and both the integral and the local transient elongational viscosity show no maximum. A detailed comparison of the experimental findings with results from literature is presented.

Teodor I. Burghelea; Zdenek Stary; Helmut Muenstedt

2010-01-13T23:59:59.000Z

433

Closure Plan for Active Low Level Burial Grounds  

SciTech Connect (OSTI)

This plan has been prepared in response to direction from the U.S. Department of Energy. The purpose of the plan is to define approaches that will be implemented to ensure protection of the public and the environment when active Low-Level Burial Grounds (LLBGs) at the Hanford Site are closed. Performance assessments for active burial grounds in the 200 East and West 200 Areas provide current estimates of potential environmental contamination and doses to the ''maximum exposed individual'' from burial ground operation and closure and compare dose estimates to performance objective dose limits for the facilities. This is an Operational Closure Plan. The intent of the guidance in DOE Order 435.1 is that this plan will be a living document, like the facility performance assessments, and will be revised periodically through the operational life of the LLBGs to reflect updated information on waste inventory. management practices, facility transition planning, schedule dates, assessments of post-closure performance, and environmental consequences. Out year dates identified in this plan are tentative. A Final Closure Plan will be prepared in the future when the timing and extent of closure-related activities for LLBGs can be established with greater certainty. After current operations at the LLBGs are concluded, this plan proposes transitioning of these facilities to the Environmental Restoration Program. This action will enable the Environmental Restoration Program to design and implement consistent and coordinated final remedial actions for active and inactive LLBGs. Active and inactive burial grounds in the 200 West and 200 East Areas are commingled. This plan describes approaches that will be implemented during Interim Closure, Final Closure, and Institutional Control Periods to prepare LLBGs for surface barriers, and the construction of barriers, as well as the scope of inspection, monitoring and maintenance practices that will be performed during and after closure. Environmental monitoring is briefly discussed in this plan. However, a more comprehensive discussion of monitoring issues is provided in a separate performance assessment monitoring plan for LLBGs. Supporting information is provided regarding the geography, climate, hydrogeology, geochemistry and land-use practices of adjacent land areas.

SKELLY, W.A.

2000-11-16T23:59:59.000Z

434

Results for the Third Quarter 2012 Tank 50 WAC Slurry Sample: Chemical and Radionuclide Contaminants  

SciTech Connect (OSTI)

This report details the chemical and radionuclide contaminant results for the characterization of the 2012 Third Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC). Information from this characterization will be used by Waste Solidification Engineering (WSE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Bannochie, C. J.

2012-10-26T23:59:59.000Z

435

Results For The Second Quarter 2013 Tank 50 WAC Slurry Sample: Chemical And Radionuclide Contaminants  

SciTech Connect (OSTI)

This report details the chemical and radionuclide contaminant results for the characterization of the 2013 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by Saltstone Facility Engineering (SFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Bannochie, Christopher J.

2013-07-31T23:59:59.000Z

436

Results for the second quarter 2014 tank 50 WAC slurry sample chemical and radionuclide contaminants  

SciTech Connect (OSTI)

This report details the chemical and radionuclide contaminant results for the characterization of the 2014 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC) in effect at that time. Information from this characterization will be used by DWPF & Saltstone Facility Engineering (DSFE) to support the transfer of low-level aqueous waste from Tank 50 to the Salt Feed Tank in the Saltstone Facility in Z-Area, where the waste will be immobilized. This information is also used to update the Tank 50 Waste Characterization System.

Bannochie, C.

2014-09-04T23:59:59.000Z

437

Effect of Saltstone Vault Roof Configuration on the Rate of Contaminant Transport  

SciTech Connect (OSTI)

At the Savannah River Site, low-level radioactive decontaminated salt solution is mixed with slag, flyash, and cement to form a grout-like material called ``Saltstone``. The Saltstone is poured into concrete vaults constructed at the Saltstone Disposal Facility (SDF). The impact of SDF on groundwater has been studied in a radiological performance assessment (PA). Sophisticated groundwater models were used to predict the groundwater flow and contaminant transport problems. The modeling effort was divided into two parts: the unsaturated-zone model and the saturated zone model. One of the major performance objectives is to show that the impacted groundwater will be in compliance with the Safe Drinking Water Act.

Hsu, R.H.; Yu, A.D.; Lam, Poh-Sang

1994-12-28T23:59:59.000Z

438

TWRS vadose zone contamination issue expert panel report  

SciTech Connect (OSTI)

When members were first canvassed for participation in the Vadose Zone Expert Panel the stated purpose for convening the Panel was to review a controversial draft report, the SX Tank Farm Report. This report was produced by a DOE Grand Junction Project Office (GJPO) contractor, RUST Geotech, now MACTEC-ERS, for the DOE Richland Office (DOERL). Three meetings were planned for June, July and August, 1995 to review the draft report and to complete a Panel report by mid-September. The Expert Panel has found its efforts confounded by various non-technical issues. The Expert Panel has chosen to address some of the non-technical issues in this Preface rather than to dilute the technical discussion that follows in the body of this independent expert panel status report (Panel Report). Rather than performing a straightforward manuscript review, the Panel was asked to resolve conflicting interpretations of gamma-ray logging measurements performed in vadose zone boreholes (drywells) surrounding the high-level radioactive wastes of the SX tank farm. There are numerous and complex technical issues that must be evaluated before the vertical and radial extent of contaminant migration at the SX tank farm can be accurately assessed. When the Panel first met in early June, 1996, it quickly became apparent that the scientific and technical issues were obscured by policy and institutional affairs which have polarized discussion among various segments of the Hanford organization. This situation reflects the kinds of institutional problems described separately in reports by the National Research Council of the National Academy of Sciences (NAS/NRC), The Hanford Tanks Environmental Impacts and Policy Choices and BmTiers to Science: Technical Management of the Department of Energy Environmental Remediation Program. The Vadose Zone Characterization Program, appears to be caught between conflicting pressures and organizational mandates, some imposed from outside DOE-RL and some self-imposed. The institutional problems they encountered include having both Tank Waste Remediation System (TWRS), the parent organization of the Vadose Zone Characterization Program and Environmental Restoration (ER), each under different regulatory controls and different organizational units, seeking to defend the status quo and discount many of the Panel`s conclusions and recommendations. The results presented in the SX Tank Farm Report, especially the visualizations, have created concern in the public sector, both on a local, personal level and on a national political level.

Shafer, D.S.

1997-05-01T23:59:59.000Z

439

Procedures for sampling radium-contaminated soils  

SciTech Connect (OSTI)

Two procedures for sampling the surface layer (0 to 15 centimeters) of radium-contaminated soil are recommended for use in remedial action projects. Both procedures adhere to the philosophy that soil samples should have constant geometry and constant volume in order to ensure uniformity. In the first procedure, a ''cookie cutter'' fashioned from pipe or steel plate, is driven to the desired depth by means of a slide hammer, and the sample extracted as a core or plug. The second procedure requires use of a template to outline the sampling area, from which the sample is obtained using a trowel or spoon. Sampling to the desired depth must then be performed incrementally. Selection of one procedure over the other is governed primarily by soil conditions, the cookie cutter being effective in nongravelly soils, and the template procedure appropriate for use in both gravelly and nongravelly soils. In any event, a minimum sample volume of 1000 cubic centimeters is recommended. The step-by-step procedures are accompanied by a description of the minimum requirements for sample documentation. Transport of the soil samples from the field is then addressed in a discussion of the federal regulations for shipping radioactive materials. Interpretation of those regulations, particularly in light of their application to remedial action soil-sampling programs, is provided in the form of guidance and suggested procedures. Due to the complex nature of the regulations, however, there is no guarantee that our interpretations of them are complete or entirely accurate. Preparation of soil samples for radium-226 analysis by means of gamma-ray spectroscopy is described.

Fleischhauer, H.L.

1985-10-01T23:59:59.000Z

440

INDEPENDENT TECHNICAL EVALUATION AND RECOMMENDATIONS FOR CONTAMINATED GROUNDWATER AT THE DEPARTMENT OF ENERGY OFFICE OF LEGACY MANAGEMENT RIVERTON PROCESSING SITE  

SciTech Connect (OSTI)

The U.S. Department of Energy Office of Legacy Management (DOE-LM) manages the legacy contamination at the Riverton, WY, Processing Site – a former uranium milling site that operated from 1958 to 1963. The tailings and associated materials were removed in 1988-1989 and contaminants are currently flushing from the groundwater. DOE-LM commissioned an independent technical team to assess the status of the contaminant flushing, identify any issues or opportunities for DOE-LM, and provide key recommendations. The team applied a range of technical frameworks – spatial, temporal, hydrological and geochemical – in performing the evaluation. In each topic area, an in depth evaluation was performed using DOE-LM site data (e.g., chemical measurements in groundwater, surface water and soil, water levels, and historical records) along with information collected during the December 2013 site visit (e.g., plant type survey, geomorphology, and minerals that were observed, collected and evaluated). A few of the key findings include: ? Physical removal of the tailings and associated materials reduced contaminant discharges to groundwater and reduced contaminant concentrations in the near-field plume. ? In the mid-field and far-field areas, residual contaminants are present in the vadose zone as a result of a variety of factors (e.g., evaporation/evapotranspiration from the capillary fringe and water table, higher water levels during tailings disposal, and geochemical processes). ? Vadose zone contaminants are widely distributed above the plume and are expected to be present as solid phase minerals that can serve as “secondary sources” to the underlying groundwater. The mineral sample collected at the site is consistent with thermodynamic predictions. ? Water table fluctuations, irrigation, infiltration and flooding will episodically solubilize some of the vadose zone secondary source materials and release contaminants to the groundwater for continued down gradient migration – extending the overall timeframe for flushing. ? Vertical contaminant stratification in the vadose zone and surficial aquifer will vary from location to location. Soil and water sampling strategies and monitoring well construction details will influence characterization and monitoring data. ? Water flows from the Wind River, beneath the Riverton Processing Site and through the plume toward the Little Wind River. This base flow pattern is influenced by seasonal irrigation and other anthropogenic activities, and by natural perturbations (e.g., flooding). ? Erosion and reworking of the sediments adjacent to the Little Wind River results in high heterogeneity and complex flow and geochemistry. Water flowing into oxbow lakes (or through areas where oxbow lakes were present in the past) will be exposed to localized geochemical conditions that favor chemical reduction (i.e., “naturally reduced zones”) and other attenuation processes. This attenuation is not sufficient to fully stabilize the plume or to reduce contaminant concentrations in the groundwater to target levels. Consistent with these observations, the team recommended increased emphasis on collecting data in the zones where secondary source minerals are projected to accumulate (e.g., just above the water table) using low cost methods such as x-ray fluorescence. The team also suggested several low cost nontraditional sources of data that have the potential to provide supplemental data (e.g., multispectral satellite imagery) to inform and improve legacy management decisions. There are a range of strategies for management of the legacy contamination in the groundwater and vadose zone near the Riverton Processing Site. These range from the current strategy, natural flushing, to intrusive remedies such as plume scale excavation of the vadose zone and pump & treat. Each option relates to the site specific conditions, issues and opportunities in a unique way. Further, each option has advantages and disadvantages that need to be weighed. Scoping evaluation was performed for three major classes

Looney, B.; Denham, M.; Eddy-Dilek, C.

2014-05-06T23:59:59.000Z

Note: This page contains sample records for the topic "maximum contaminant levels" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Period-luminosity and period-luminosity-colour relations for Mira variables at maximum light  

E-Print Network [OSTI]

In this paper we confirm the existence of period-luminosity (PL) and period-luminosity-colour (PLC) relations at maximum light for O and C Mira variables in the LMC. We demonstrate that in the J and H bands the maximum light PL relations have a significantly smaller dispersion than their counterparts at mean light, while the K band and bolometric PL relations have a dispersion comparable to that at mean light. In the J, H and K bands the fitted PL relations for the O Miras are found to have smaller dispersion than those for the C Miras, at both mean and maximum light, while the converse is true for the relations based on bolometric magnitudes. The inclusion of a non-zero log period term is found to be highly significant in all cases except that of the C Miras in the J band, for which the data are found to be consistent with having constant absolute magnitude. This suggests the possibility of employing C Miras as standard candles. We suggest both a theoretical justification for the existence of Mira PL relations at maximum light and a possible explanation of why these relations should have a smaller dispersion than at mean light. The existence of such maximum light relations offers the possibility of extending the range and improving the accuracy of the Mira distance scale to Galactic globular clusters and to other galaxies.

S. M. Kanbur; M. A. Hendry; D. Clarke

1997-04-14T23:59:59.000Z

442

On the maximum value of the cosmic abundance of oxygen and the oxygen yield  

E-Print Network [OSTI]

We search for the maximum oxygen abundance in spiral galaxies. Because this maximum value is expected to occur in the centers of the most luminous galaxies, we have constructed the luminosity - central metallicity diagram for spiral galaxies, based on a large compilation of existing data on oxygen abundances of HII regions in spiral galaxies. We found that this diagram shows a plateau at high luminosities (-22.3 oxygen abundance 12+log(O/H) ~ 8.87. This provides strong evidence that the oxygen abundance in the centers of the most luminous metal-rich galaxies reaches the maximum attainable value of oxygen abundance. Since some fraction of the oxygen (about 0.08 dex) is expected to be locked into dust grains, the maximum value of the true gas+dust oxygen abundance in spiral galaxies is 12+log(O/H) ~ 8.95. This value is a factor of ~ 2 higher than the recently estimated solar value. Based on the derived maximum oxygen abundance in galaxies, we found the oxygen yield to be about 0.0035, depending on the fraction of oxygen incorporated into dust grains.

L. S. Pilyugin; T. X. Thuan; J. M. Vilchez

2007-01-11T23:59:59.000Z

443

HFIR Vessel Maximum Permissible Pressures for Operating Period 26 to 50 EFPY (100 MW)  

SciTech Connect (OSTI)

Extending the life of the HFIR pressure vessel from 26 to 50 EFPY (100 MW) requires an updated calculation of the maximum permissible pressure for a range in vessel operating temperatures (40-120 F). The maximum permissible pressure is calculated using the equal-potential method, which takes advantage of knowledge gained from periodic hydrostatic proof tests and uses the test conditions (pressure, temperature, and frequency) as input. The maximum permissible pressure decreases with increasing time between hydro tests but is increased each time a test is conducted. The minimum values that occur just prior to a test either increase or decrease with time, depending on the vessel temperature. The minimum value of these minimums is presently specified as the maximum permissible pressure. For three vessel temperatures of particular interest (80, 88, and 110 F) and a nominal time of 3.0 EFPY(100 MVV)between hydro tests, these pressures are 677, 753, and 850 psi. For the lowest temperature of interest (40 F), the maximum permissible pressure is 295 psi.

Cheverton, R.D.; Inger, J.R.

1999-01-01T23:59:59.000Z

444

Post-remediation biomonitoring of pesticides and other contaminants in marine waters and sediment near the United Heckathorn Superfund Site, Richmond, California  

SciTech Connect (OSTI)

Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in February 1999 from four stations near Lauritzen Canal in Richmond, California, for Year 2 of post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and dichlorodiphenyl trichloroethane (DDT) were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Concentrations of dieldrin and total DDT in water and total DDT in tissue were compared with Year 1 of post-remediation monitoring, and with preremediation data from the California State Mussel Watch program (tissues) and the Ecological Risk Assessment for the United Heckathorn Superfund Site (tissues and water). Mussel tissues were also analyzed for polychlorinated biphenyls (PCB), which were detected in sediment samples. Chlorinated pesticide concentrations in water samples were similar to preremediation levels and did not meet remediation goals. Mean dieidrin concentrations in water ranged from 0.62 rig/L to 12.5 ng/L and were higher than the remediation goal (0.14 ng/L) at all stations. Mean total DDT concentrations in water ranged from 14.4 ng/L to 62.3 ng/L and exceeded the remediation goal (0.59 ng/L) at all stations. The highest concentrations of both pesticides were found at the Lauritzen Canal/End station. Despite exceedence of the remediation goals, chlorinated pesticide concentrations in Lauritzen Canal water samples were notably lower in 1999 than in 1998. Tissue samples from biomonitoring organisms (mussels) provide an indication of the longer-term integrated exposure to contaminants in the water column, which overcomes the limitations of grab samples of water. Biomonitoring results indicated that the bioavailability of chlorinated pesticides has been reduced from preremediation levels both in the dredged area and throughout Richmond Harbor. Total DDT and dieldrin concentrations in mussel tissues were dramatically lower than measured levels from preremediation surveys and also lower than Year 1 levels from post-remediation biomonitoring. The lowest levels were found at the Richmond Inner Harbor Channel station (4.1 {micro}g/kg total DDT and 0.59 {micro}g/kg dieldrin, wet weight; mean of resident and transplant mussels). Mean chlorinated pesticide concentrations were highest at Lauritzen Canal/End (82 {micro}g/kg total DDT and 7.1 {micro}g/kg dieldrin, wet weight), followed by Lauritzen Canal/Mouth (22 {micro}/kg total DDT and 1.7 {micro}g/kg dieldrin, wet weight) and Santa Fe Channel/End (7.5 {micro}g/kg total DOT and 0.61 {micro}g/kg dieldrin, wet weight). These levels are 95% to 99% lower than those recorded by the California State Mussel Watch program prior to EPA's response actions. The levels of PCBs in mussel tissue were also reduced by 93% to 97% from preremediation levels. Surface sediment concentrations of dieldrin and DDT in November 1998 were highest in samples from the head or north end of Lauritzen Canal and progressively lower toward the mouth, or south end. Total DDT ranged from 130 ppm (dry weight) at the north end to 3 ppm at the south end. Dieldrin concentrations decreased from 3,270 ppb (dry weight) at the north end to 52 ppb at the south end. These results confirmed elevated pesticide concentrations in sediments collected from Lauritzen Channel by Anderson et al. (1999). The pesticide concentrations were lower than maximum concentrations found in the 1993 Remedial Investigation but comparable to the median levels measured before remediation was completed. Sediment analyses also showed the presence of elevated PCB aroclor 1254, and very high levels of polynuclear aromatic hydrocarbons (PAH) in Lauritzen Channel.

LD Antrim; NP Kohn

2000-05-26T23:59:59.000Z

445

Eliminating the Renormalization Scale Ambiguity for Top-Pair Production Using the Principle of Maximum Conformality  

SciTech Connect (OSTI)

The uncertainty in setting the renormalization scale in finite-order perturbative QCD predictions using standard methods substantially reduces the precision of tests of the Standard Model in collider experiments. It is conventional to choose a typical momentum transfer of the process as the renormalization scale and take an arbitrary range to estimate the uncertainty in the QCD prediction. However, predictions using this procedure depend on the choice of renormalization scheme, leave a non-convergent renormalon perturbative series, and moreover, one obtains incorrect results when applied to QED processes. In contrast, if one fixes the renormalization scale using the Principle of Maximum Conformality (PMC), all non-conformal {l_brace}{beta}{sub i}{r_brace}-terms in the perturbative expansion series are summed into the running coupling, and one obtains a unique, scale-fixed, scheme-independent prediction at any finite order. The PMC renormalization scale {mu}{sub R}{sup PMC} and the resulting finite-order PMC prediction are both to high accuracy independent of choice of the initial renormalization scale {mu}{sub R}{sup init}, consistent with renormalization group invariance. Moreover, after PMC scale-setting, the n!-growth of the pQCD expansion is eliminated. Even the residual scale-dependence at fixed order due to unknown higher-order {l_brace}{beta}{sub i}{r_brace}-terms is substantially suppressed. As an application, we apply the PMC procedure to obtain NNLO predictions for the t{bar t}-pair hadroproduction cross-section at the Tevatron and LHC colliders. There are no renormalization scale or scheme uncertainties, thus greatly improving the precision of the QCD prediction. The PMC prediction for {sigma}{sub t{bar t}} is larger in magnitude in comparison with the conventional scale-setting method, and it agrees well with the present Tevatron and LHC data. We also verify that the initial scale-independence of the PMC prediction is satisfied to high accuracy at the NNLO level: the total cross-section remains almost unchanged even when taking very disparate initial scales {mu}{sub R}{sup init} equal to m{sub t}, 20 m{sub t}, {radical}s.

Brodsky, Stanley J.; /SLAC; Wu, Xing-Gang; /Chongqing U.

2012-04-02T23:59:59.000Z

446

Geotechnical properties of oil-contaminated Kuwaiti sand  

SciTech Connect (OSTI)

Large quantities of oil-contaminated sands resulted from exploded oil wells, burning oil fires, the destruction of oil storage tanks, and the formation of oil lakes in Kuwait at the end of the Gulf War. An extensive laboratory testing program was carried out to determine the geotechnical characteristics of this material. Testing included basic properties, compaction and permeability tests, and triaxial and consolidation tests on clean and contaminated sand at the same relative density. Contaminated specimens were prepared by mixing the sand with oil in the amount of 6% by weight or less to match field conditions. The influence of the type of oil, and relative density was also investigated by direct shear tests. The results indicated a small reduction in strength and permeability and an increase in compressibility due to contamination. The preferred method of disposal of this material is to use it as a stabilizing material for other projects such as road construction.

Al-Sanad, H.A.; Eid, W.K.; Ismael, N.F. [Kuwait Univ., Safat (Kuwait). Dept. of Civil Engineering] [Kuwait Univ., Safat (Kuwait). Dept. of Civil Engineering

1995-05-01T23:59:59.000Z

447

Scale-dependent desorption of uranium from contaminated subsurface...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

to investigate the scale-dependent desorption of uranyl U(VI) from a contaminated sediment collected from the Hanford 300 Area at the US Department of Energy (DOE) Hanford...

448

Chapter 8: Modelling Sediment Records of Atmospherically Deposited Contaminants  

E-Print Network [OSTI]

73 Chapter 8: Modelling Sediment Records of Atmospherically Deposited Contaminants 8.1. Catchment the Water Column...............................................79 8.3 Water Column to Bottom Sediment Transfer......................................80 #12;Chapter 8: Modelling Sediment Records... 74 8

Short, Daniel

449

Transuranic contaminated waste form characterization and data base  

SciTech Connect (OSTI)

This volume contains 5 appendices. Title listing are: technologies for recovery of transuranics; nondestructive assay of TRU contaminated wastes; miscellaneous waste characteristics; acceptance criteria for TRU waste; and TRU waste treatment technologies.

Kniazewycz, B.G.; McArthur, W.C.

1980-07-01T23:59:59.000Z

450

Rapid and Robust Detection Methods for Poison and Microbial Contamination  

E-Print Network [OSTI]

Real-time on-site monitoring of analytes is currently in high demand for food contamination, water, medicines, and ingestible household products that were never tested appropriately. Here we introduce chemical methods for ...

Lu, Peter J.

451

Biodegradation of petroleum hydrocarbons in contaminated aqueous and sediment environments  

E-Print Network [OSTI]

Six bioremediation methods were tested in laboratory microcosms using field soil and water samples from within the fire-wall area of a petroleum storage tank. This soil had been intermittently contaminated with Bunker C fuel oil and other petroleum...

Mills, Marc Allyn

1994-01-01T23:59:59.000Z

452

An integrated treatment methodology for PCB-contaminated soil  

E-Print Network [OSTI]

This study proposed coupling two different treatment technologies, chemical dehalogenation using potassium polyethylene glycol (KPEG) and bioremediation, to optimize the destruction and detoxification of PCB-contaminated soil. Changes in toxicity...

Garcia, Shannon S

1995-01-01T23:59:59.000Z

453

Radon induced surface contaminations in low background experiments  

SciTech Connect (OSTI)

In neutrinoless double-beta decay and dark matter searches, one of the main issues is to increase the experimental sensitivity through careful material selection and production, minimizing the background contributions. In order to achieve the required, extremely low, counting rates, very stringent requirements must be fulfilled in terms of bulk material radiopurity. As the experimental sensitivity increases, the bulk impurities in the detector components decrease, and surface contaminations start to play an increasingly significant role In fully active detectors, like cryogenic particle detectors, surface contaminations are a critical issue (as shown by the CUORICINO experiment). {sup 222}Rn is by far the most intense source of airborne radioactivity, and if a radio-pure material is exposed to environment where the Radon concentration is not minimized, {sup 210}Pb and {sup 210}Po contaminations can occur. The mechanisms and the dynamics of Radon-induced surface contaminations are reviewed, and specific solutions to prevent and to reject the induced background are presented.

Pattavina, L. [INFN - Laboratori Nazionali del Gran Sasso, I-67010 Assergi (AQ) (Italy)] [INFN - Laboratori Nazionali del Gran Sasso, I-67010 Assergi (AQ) (Italy)

2013-08-08T23:59:59.000Z

454

Lead Groundwater Contamination of Groundwater in the Northeast ...  

E-Print Network [OSTI]

The detailed description of the migration of pollutants is fundamental for the groundwater monitoring and it ... historical data with a, groundwater contamination sampling for water quality analyses ... can be toxic to living organisms. Lead can ...

2001-03-12T23:59:59.000Z

455

Nitrate contamination of domestic potable water supplies: a social problem  

SciTech Connect (OSTI)

Nitrate contamination of potable water supplies is a recognized health hazard. Potentially, the contamination of private drinking water supplies could be a problem in the rural Palouse area of Idaho and Washington. Studies have shown that 12% of the rural population of Whitman County, Washington, may be drinking water containing nitrates in excess of the national standard. Yet there is no organized concern about this potential health hazard among local citizens. After reviewing the literature on nitrate contamination of ground water and discussing nitrate contamination of private potable water supplies in the Palouse, we use a social movement theory of social problems to explain why this situation has not been defined as a public health problem.

Holmes, T.; Jensen, E.L.; Conway, J.B.

1985-01-01T23:59:59.000Z

456

Salmonella contamination during production of domestic and imported canaloupe  

E-Print Network [OSTI]

In this study, 8 cantaloupe farms and packing sheds from the United States (U.S.) and Mexico were sampled to evaluate cantaloupe contamination with Salmonella and Escherichia coli during production and processing. Samples collected from external...

Uribe, Imelda Mercado

2002-01-01T23:59:59.000Z

457

Detection of contaminants using a MEMS FAIMS sensor  

E-Print Network [OSTI]

Detecting the presence of contaminants in water is a critical mission, but thorough testing often requires extensive time at a remote facility. A MEMS implementation of a FAIMS (High-Field Asymmetric-Waveform Ion Mobility ...

Carr, Kristin (Kristin Malia)

2005-01-01T23:59:59.000Z

458

Mechanisms of metal release from contaminated coastal sediments  

E-Print Network [OSTI]

The fate of trace metals in contaminated coastal sediments is poorly understood, yet critical for effective coastal management. The aim of this thesis is to investigate and quantify the mechanisms leading to the release ...

Kalnejais, Linda H

2005-01-01T23:59:59.000Z

459

Catalytic destruction of groundwater contaminants in reactive extraction wells  

DOE Patents [OSTI]

A system for remediating groundwater contaminated with halogenated solvents, certain metals and other inorganic species based on catalytic reduction reactions within reactive well bores. The groundwater treatment uses dissolved hydrogen as a reducing agent in the presence of a metal catalyst, such a palladium, to reduce halogenated solvents (as well as other substituted organic compounds) to harmless species (e.g., ethane or methane) and immobilize certain metals to low valence states. The reactive wells function by removing water from a contaminated water-bearing zone, treating contaminants with a well bore using catalytic reduction, and then reinjecting the treated effluent into an adjacent water-bearing zone. This system offers the advantages of a compact design with a minimal surface footprint (surface facilities) and the destruction of a broad suite of contaminants without generating secondary waste streams.

McNab, Jr., Walt W. (Concord, CA); Reinhard, Martin (Stanford, CA)

2002-01-01T23:59:59.000Z

460

Mercury-Contaminated Hydraulic Mining Debris in San Francisco Bay  

E-Print Network [OSTI]

S, and Flegal AR 2008. Mercury in the San Francisco Estuary.may 2010 Mercury-Contaminated Hydraulic Mining Debris in Sancontaminants such as ele- mental mercury and cyanide used in

Bouse, Robin M; Fuller, Christopher C; Luoma, Sam; Hornberger, Michelle I; Jaffe, Bruce E; Smith, Richard E

2010-01-01T23:59:59.000Z