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Title: Chromium in Groundwater beneath Los Alamos National Laboratory

Authors:
 [1]
  1. Los Alamos National Laboratory
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Environmental Management (EM)
OSTI Identifier:
1351250
Report Number(s):
LA-UR-17-22577
DOE Contract Number:
AC52-06NA25396
Resource Type:
Conference
Resource Relation:
Conference: Meeting with Yasuhiro Nakai ; 2017-03-27 - 2017-03-27 ; Los Alamos, New Mexico, United States
Country of Publication:
United States
Language:
English
Subject:
Environmental Protection

Citation Formats

Katzman, Danny. Chromium in Groundwater beneath Los Alamos National Laboratory. United States: N. p., 2017. Web.
Katzman, Danny. Chromium in Groundwater beneath Los Alamos National Laboratory. United States.
Katzman, Danny. Thu . "Chromium in Groundwater beneath Los Alamos National Laboratory". United States. doi:. https://www.osti.gov/servlets/purl/1351250.
@article{osti_1351250,
title = {Chromium in Groundwater beneath Los Alamos National Laboratory},
author = {Katzman, Danny},
abstractNote = {},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Mar 30 00:00:00 EDT 2017},
month = {Thu Mar 30 00:00:00 EDT 2017}
}

Conference:
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  • Numerical simulations are used to predict the migration of radionuclides from the disposal units at Material Disposal Area G through the vadose zone and into the main aquifer in support of a radiological performance assessment and composite analysis for the site. The calculations are performed with the finite element code, FEHM. The transport of nuclides through the vadose zone is computed using a three-dimensional model that describes the complex mesa top geology of the site. The model incorporates the positions and inventories of thirty-four disposal pits and four shaft fields located at Area G as well as those of proposedmore » future pits and shafts. Only three nuclides, C-14, Tc-99, and I-129, proved to be of concern for the groundwater pathway over a 10,000-year period. The spatial and temporal flux of these three nuclides from the vadose zone is applied as a source term for the three-dimensional saturated zone model of the main aquifer that underlies the site. The movement of these nuclides in the aquifer to a downstream location is calculated, and aquifer concentrations are converted to doses. Doses related to aquifer concentrations are six or more orders of magnitude lower than allowable Department of Energy performance objectives for low-level radioactive waste sites. Numerical studies were used to better understand vadose-zone flow through the dry mesa-top environment at Area G. These studies helped define the final model used to model flow and transport through the vadose zone. The study of transient percolation indicates that a steady flow vadose-zone model is adequate for computing contaminant flux to the aquifer. The fracture flow studies and the investigation of the effect of basalt and pumice properties helped us define appropriate hydrologic properties for the modeling. Finally, the evaporation study helped to justify low infiltration rates.« less
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