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

Title: Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data

Abstract

In this study, porewater chloride data from Yucca Mountain, Nevada, are analyzed and modeled by 3-D chemical transport simulations and analytical methods. The simulation modeling approach is based on a continuum formulation of coupled multiphase fluid flow and tracer transport processes through fractured porous rock, using a dual-continuum concept. Infiltration-rate calibrations were using the pore water chloride data. Model results of chloride distributions were improved in matching the observed data with the calibrated infiltration rates. Statistical analyses of the frequency distribution for overall percolation fluxes and chloride concentration in the unsaturated zone system demonstrate that the use of the calibrated infiltration rates had insignificant effect on the distribution of simulated percolation fluxes but significantly changed the predicated distribution of simulated chloride concentrations. An analytical method was also applied to model transient chloride transport. The method was verified by 3-D simulation results as able to capture major chemical transient behavior and trends. Effects of lateral flow in the Paintbrush nonwelded unit on percolation fluxes and chloride distribution were studied by 3-D simulations with increased horizontal permeability. The combined results from these model calibrations furnish important information for the UZ model studies, contributing to performance assessment of the potential repository.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Civilian Radioactive Waste Management. Yucca Mountain Site Characterization Office (US)
OSTI Identifier:
840320
Report Number(s):
LBNL-49871
R&D Project: 81BB11; TRN: US0501961
DOE Contract Number:
AC03-76SF00098
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Contaminant Hydrology; Journal Volume: 62-63; Journal Issue: SI; Other Information: Submitted to Journal of Contaminant Hydrology: Volume 62-63, Special Issue; Journal Publication Date: 04-05/2003; PBD: 1 Sep 2002
Country of Publication:
United States
Language:
English
Subject:
12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; 58 GEOSCIENCES; CALIBRATION; CHLORIDES; DISTRIBUTION; FLUID FLOW; NEVADA; PERFORMANCE; PERMEABILITY; SIMULATION; TRANSIENTS; TRANSPORT; WATER; YUCCA MOUNTAIN; CHLORIDE UNSATURATED ZONE YUCCA MOUNTAIN GEOCHEMISTRY INFILTRATION MAP PERCOLATION.

Citation Formats

Liu, Jianchun, Sonnenthal, Eric L., and Bodvarsson, Gudmundur S.. Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data. United States: N. p., 2002. Web.
Liu, Jianchun, Sonnenthal, Eric L., & Bodvarsson, Gudmundur S.. Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data. United States.
Liu, Jianchun, Sonnenthal, Eric L., and Bodvarsson, Gudmundur S.. 2002. "Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data". United States. doi:. https://www.osti.gov/servlets/purl/840320.
@article{osti_840320,
title = {Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data},
author = {Liu, Jianchun and Sonnenthal, Eric L. and Bodvarsson, Gudmundur S.},
abstractNote = {In this study, porewater chloride data from Yucca Mountain, Nevada, are analyzed and modeled by 3-D chemical transport simulations and analytical methods. The simulation modeling approach is based on a continuum formulation of coupled multiphase fluid flow and tracer transport processes through fractured porous rock, using a dual-continuum concept. Infiltration-rate calibrations were using the pore water chloride data. Model results of chloride distributions were improved in matching the observed data with the calibrated infiltration rates. Statistical analyses of the frequency distribution for overall percolation fluxes and chloride concentration in the unsaturated zone system demonstrate that the use of the calibrated infiltration rates had insignificant effect on the distribution of simulated percolation fluxes but significantly changed the predicated distribution of simulated chloride concentrations. An analytical method was also applied to model transient chloride transport. The method was verified by 3-D simulation results as able to capture major chemical transient behavior and trends. Effects of lateral flow in the Paintbrush nonwelded unit on percolation fluxes and chloride distribution were studied by 3-D simulations with increased horizontal permeability. The combined results from these model calibrations furnish important information for the UZ model studies, contributing to performance assessment of the potential repository.},
doi = {},
journal = {Journal of Contaminant Hydrology},
number = SI,
volume = 62-63,
place = {United States},
year = 2002,
month = 9
}
  • This paper presents a large-scale modeling study characterizing fluid flow and tracer transport in the unsaturated zone of Yucca Mountain, Nevada, the proposed underground repository site for storing high-level radioactive waste. The modeling study is conducted using a three-dimensional numerical model, which incorporates a wide variety of field data and takes into account the coupled processes of flow and transport in Yucca Mountain's highly heterogeneous, unsaturated, fractured porous rock. The modeling approach is based on a dual-continuum formulation. Using different conceptual models of unsaturated flow, various scenarios of current and future climate conditions and their effects on the unsaturated zonemore » are evaluated to aid in the assessment of the repository's system performance. These models are calibrated against field-measured data. Model-predicted flow and transport processes under current and future climates are discussed.« less
  • No abstract prepared.
  • No abstract prepared.
  • Yucca Mountain, Nevada, is being investigated to determine its suitability for a mined geologic repository for the permanent storage of high-level nuclear waste. If a license is granted, the repository would be constructed in partially saturated welded tuff at {approx}300 m below land surface. The presence of an unsaturated zone that ranges from 300 to 750 m thick, combined with an arid environment, is presumed to be a major asset in the ability of the rocks to isolate nuclear waste. Therefore, much of the site-characterization effort will focus on evaluating the hydrology of the unsaturated zone. On the basis ofmore » existing data and the general principles of unsaturated flow, a conceptual model of moisture flow in this environment has been developed to guide site characterization.« less
  • No abstract prepared.