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Title: Development of the Conceptual Models for Chemical Conditions and Hydrology Used in the 1996 Performance Assessment for the Waste Isolation Pilot Plant

Abstract

The Waste Isolation Pilot Plant (WIPP) is a US Department of Energy (DOE) facility for the permanent disposal of defense-related transuranic (TRU) waste. US Environmental Protection Agency (EPA) regulations specify that the DOE must demonstrate on a sound basis that the WIPP disposal system will effectively contain long-lived alpha-emitting radionuclides within its boundaries for 10,000 years following closure. In 1996, the DOE submitted the ''40 CFR Part 191 Compliance Certification Application for the Waste Isolation Pilot Plant'' (CCA) to the EPA. The CCA proposed that the WIPP site complies with EPA's regulatory requirements. Contained within the CCA are descriptions of the scientific research conducted to characterize the properties of the WIPP site and the probabilistic performance assessment (PA) conducted to predict the containment properties of the WIPP disposal system. In May 1998, the EPA certified that the TRU waste disposal at the WIPP complies with its regulations. Waste disposal operations at WIPP commenced on March 28, 1999. The 1996 WIPP PA model of the disposal system included conceptual and mathematical representations of key hydrologic and geochemical processes. These key processes were identified over a 22-year period involving data collection, data interpretation, computer models, and sensitivity studies to evaluate the importancemore » of uncertainty and of processes that were difficult to evaluate by other means. Key developments in the area of geochemistry were the evaluation of gas generation mechanisms in the repository; development of a model of chemical conditions in the repository and actinide concentrations in brine; selecting MgO backfill and demonstrating its effects experimentally; and determining the chemical retardation capability of the Culebra. Key developments in the area of hydrology were evacuating the potential for groundwater to dissolve the Salado Formation (the repository host formation), development of a regional model for hydrologic conditions, development of a stochastic, probabilistic representation of hydraulic properties in the Culebra Member of the Rustler Formation; characterization of physical transport in the Culebra, and the evaluation of brine and gas flow in the Salado. Additional confidence in the conceptual models used in the 1996 WIPP PA was gained through independent peer review in many stages of their development.« less

Authors:
Publication Date:
Research Org.:
Sandia National Labs., Albuquerque, NM (US); Sandia National Labs., Livermore, CA (US)
Sponsoring Org.:
US Department of Energy (US)
OSTI Identifier:
12668
Report Number(s):
SAND99-2331J
Journal ID: ISSN 0951-8320; TRN: US0200779
DOE Contract Number:  
AC04-94AL85000
Resource Type:
Journal Article
Journal Name:
Reliability Engineering and System Safety
Additional Journal Information:
Journal Volume: 69; Journal Issue: 1-3; Other Information: Supercedes report DE00012668; Submitted to Reliability Engineering and System Safety; PBD: 24 May 2000; PBD: 24 May 2000; Journal ID: ISSN 0951-8320
Country of Publication:
United States
Language:
English
Subject:
12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; ALPHA-BEARING WASTES; GAS FLOW; GEOCHEMISTRY; HYDROLOGY; PERFORMANCE; RADIOACTIVE WASTE DISPOSAL; GEOLOGIC MODELS; SITE CHARACTERIZATION

Citation Formats

LARSON, KURT W. Development of the Conceptual Models for Chemical Conditions and Hydrology Used in the 1996 Performance Assessment for the Waste Isolation Pilot Plant. United States: N. p., 2000. Web. doi:10.1016/S0951-8320(00)00025-9.
LARSON, KURT W. Development of the Conceptual Models for Chemical Conditions and Hydrology Used in the 1996 Performance Assessment for the Waste Isolation Pilot Plant. United States. doi:10.1016/S0951-8320(00)00025-9.
LARSON, KURT W. Wed . "Development of the Conceptual Models for Chemical Conditions and Hydrology Used in the 1996 Performance Assessment for the Waste Isolation Pilot Plant". United States. doi:10.1016/S0951-8320(00)00025-9. https://www.osti.gov/servlets/purl/12668.
@article{osti_12668,
title = {Development of the Conceptual Models for Chemical Conditions and Hydrology Used in the 1996 Performance Assessment for the Waste Isolation Pilot Plant},
author = {LARSON, KURT W},
abstractNote = {The Waste Isolation Pilot Plant (WIPP) is a US Department of Energy (DOE) facility for the permanent disposal of defense-related transuranic (TRU) waste. US Environmental Protection Agency (EPA) regulations specify that the DOE must demonstrate on a sound basis that the WIPP disposal system will effectively contain long-lived alpha-emitting radionuclides within its boundaries for 10,000 years following closure. In 1996, the DOE submitted the ''40 CFR Part 191 Compliance Certification Application for the Waste Isolation Pilot Plant'' (CCA) to the EPA. The CCA proposed that the WIPP site complies with EPA's regulatory requirements. Contained within the CCA are descriptions of the scientific research conducted to characterize the properties of the WIPP site and the probabilistic performance assessment (PA) conducted to predict the containment properties of the WIPP disposal system. In May 1998, the EPA certified that the TRU waste disposal at the WIPP complies with its regulations. Waste disposal operations at WIPP commenced on March 28, 1999. The 1996 WIPP PA model of the disposal system included conceptual and mathematical representations of key hydrologic and geochemical processes. These key processes were identified over a 22-year period involving data collection, data interpretation, computer models, and sensitivity studies to evaluate the importance of uncertainty and of processes that were difficult to evaluate by other means. Key developments in the area of geochemistry were the evaluation of gas generation mechanisms in the repository; development of a model of chemical conditions in the repository and actinide concentrations in brine; selecting MgO backfill and demonstrating its effects experimentally; and determining the chemical retardation capability of the Culebra. Key developments in the area of hydrology were evacuating the potential for groundwater to dissolve the Salado Formation (the repository host formation), development of a regional model for hydrologic conditions, development of a stochastic, probabilistic representation of hydraulic properties in the Culebra Member of the Rustler Formation; characterization of physical transport in the Culebra, and the evaluation of brine and gas flow in the Salado. Additional confidence in the conceptual models used in the 1996 WIPP PA was gained through independent peer review in many stages of their development.},
doi = {10.1016/S0951-8320(00)00025-9},
journal = {Reliability Engineering and System Safety},
issn = {0951-8320},
number = 1-3,
volume = 69,
place = {United States},
year = {2000},
month = {5}
}