skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Monitored Natural Attenuation of ino9rganic Contaminants Treatability Study Final Report

Abstract

The identification and quantification of key natural attenuation processes for inorganic contaminants at D-Area is detailed herein. Two overarching goals of this evaluation of monitored natural attenuation (MNA) as a remediation strategy were (1) to better define the availability of inorganic contaminants as potential sources for transport to groundwater and uptake by environmental receptors and (2) to understand the site-specific mechanisms controlling attenuation of these inorganic contaminants through tandem geochemical and biological characterization. Data collected in this study provides input for more appropriate site groundwater transport models. Significant natural attenuation is occurring at D-Area as evidenced by relatively low aqueous concentrations of constituents of concern (COCs) (Be, Ni, U, and As) at all locations characterized and the decrease in groundwater concentrations with increasing distance from the source. The observed magnitude of decrease in groundwater concentrations of COCs with distance from the D-Area Coal Pile Runoff Basin (DCPRB) could not be accounted for by the modeled physical attenuation processes of dilution/dispersion. This additional attenuation, i.e., the observed difference between the groundwater concentrations of COCs and the modeled physical attenuation, is due to biogeochemical processes occurring at the D-Area. In tandem geochemical and microbiological characterization studies designed to evaluate the mechanisms contributingmore » to natural attenuation, pH was the single parameter found to be most predictive of contaminant attenuation. The increasing pH with distance from the source is likely responsible for increased sorption of COCs to soil surfaces within the aquifer at D-Area. Importantly, because the sediments appear to have a high buffering capacity, the acid emanating from the DCPRB has been neutralized by the soil, and these conditions have led to large Kd values at the site. Two major types of soils are present at D-Area and were evaluated in this study: upland subsurface soils associated with a low pH/high sulfate/metals plume down-gradient of the D-Area Coal Pile Runoff Basin (DCPRB) and surface ash material discharged to the wetland from the D-Area Ash Basin (488-D). Sequential extraction studies were carried out to better define the availability of inorganic contaminant sources at D-Area.« less

Authors:
Publication Date:
Research Org.:
Savannah River Site (SRS), Aiken, SC (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
890152
Report Number(s):
WSRC-TR-2004-00124
TRN: US200620%%722
DOE Contract Number:  
DE-AC09-96SR18500
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; AQUIFERS; ATTENUATION; AVAILABILITY; CAPACITY; COAL; EVALUATION; PLUMES; RUNOFF; SEDIMENTS; SOILS; SORPTION; TRANSPORT; WETLANDS

Citation Formats

Crapse, K. Monitored Natural Attenuation of ino9rganic Contaminants Treatability Study Final Report. United States: N. p., 2004. Web. doi:10.2172/890152.
Crapse, K. Monitored Natural Attenuation of ino9rganic Contaminants Treatability Study Final Report. United States. https://doi.org/10.2172/890152
Crapse, K. 2004. "Monitored Natural Attenuation of ino9rganic Contaminants Treatability Study Final Report". United States. https://doi.org/10.2172/890152. https://www.osti.gov/servlets/purl/890152.
@article{osti_890152,
title = {Monitored Natural Attenuation of ino9rganic Contaminants Treatability Study Final Report},
author = {Crapse, K},
abstractNote = {The identification and quantification of key natural attenuation processes for inorganic contaminants at D-Area is detailed herein. Two overarching goals of this evaluation of monitored natural attenuation (MNA) as a remediation strategy were (1) to better define the availability of inorganic contaminants as potential sources for transport to groundwater and uptake by environmental receptors and (2) to understand the site-specific mechanisms controlling attenuation of these inorganic contaminants through tandem geochemical and biological characterization. Data collected in this study provides input for more appropriate site groundwater transport models. Significant natural attenuation is occurring at D-Area as evidenced by relatively low aqueous concentrations of constituents of concern (COCs) (Be, Ni, U, and As) at all locations characterized and the decrease in groundwater concentrations with increasing distance from the source. The observed magnitude of decrease in groundwater concentrations of COCs with distance from the D-Area Coal Pile Runoff Basin (DCPRB) could not be accounted for by the modeled physical attenuation processes of dilution/dispersion. This additional attenuation, i.e., the observed difference between the groundwater concentrations of COCs and the modeled physical attenuation, is due to biogeochemical processes occurring at the D-Area. In tandem geochemical and microbiological characterization studies designed to evaluate the mechanisms contributing to natural attenuation, pH was the single parameter found to be most predictive of contaminant attenuation. The increasing pH with distance from the source is likely responsible for increased sorption of COCs to soil surfaces within the aquifer at D-Area. Importantly, because the sediments appear to have a high buffering capacity, the acid emanating from the DCPRB has been neutralized by the soil, and these conditions have led to large Kd values at the site. Two major types of soils are present at D-Area and were evaluated in this study: upland subsurface soils associated with a low pH/high sulfate/metals plume down-gradient of the D-Area Coal Pile Runoff Basin (DCPRB) and surface ash material discharged to the wetland from the D-Area Ash Basin (488-D). Sequential extraction studies were carried out to better define the availability of inorganic contaminant sources at D-Area.},
doi = {10.2172/890152},
url = {https://www.osti.gov/biblio/890152}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed May 19 00:00:00 EDT 2004},
month = {Wed May 19 00:00:00 EDT 2004}
}