Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Groundwater Flow Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada, Revision 0

Technical Report ·
DOI:https://doi.org/10.2172/921957· OSTI ID:921957

The Pahute Mesa groundwater flow model supports the FFACO UGTA corrective action strategy objective of providing an estimate of the vertical and horizontal extent of contaminant migration for each CAU in order to predict contaminant boundaries. A contaminant boundary is the model-predicted perimeter that defines the extent of radionuclide-contaminated groundwater from underground nuclear testing above background conditions exceeding Safe Drinking Water Act (SDWA) standards. The contaminant boundary will be composed of both a perimeter boundary and a lower hydrostratigraphic unit (HSU) boundary. Additional results showing contaminant concentrations and the location of the contaminant boundary at selected times will also be presented. These times may include the verification period, the end of the five-year proof-of-concept period, as well as other times that are of specific interest. The FFACO (1996) requires that the contaminant transport model predict the contaminant boundary at 1,000 years and “at a 95% level of confidence.” The Pahute Mesa Phase I flow model described in this report provides, through the flow fields derived from alternative hydrostratigraphic framework models (HFMs) and recharge models, one part of the data required to compute the contaminant boundary. Other components include the simplified source term model, which incorporates uncertainty and variability in the factors that control radionuclide release from an underground nuclear test (SNJV, 2004a), and the transport model with the concomitant parameter uncertainty as described in Shaw (2003). The uncertainty in all the above model components will be evaluated to produce the final contaminant boundary. This report documents the development of the groundwater flow model for the Central and Western Pahute Mesa CAUs.

Research Organization:
Stoller-Navarro Joint Venture
Sponsoring Organization:
USDOE
DOE Contract Number:
AC52-03NA99205
OSTI ID:
921957
Report Number(s):
S-N/99205--076
Country of Publication:
United States
Language:
English