WIPP (Waste Isolation Pilot Plant) performance assessment: A 1990 snapshot of compliance with 40 CFR 191, Subpart B

The United States Department of Energy (DOE) plans to use the Waste Isolation Pilot plant (WIPP) in southeastern New Mexico for disposal of transuranic wastes generated by defense programs. The DOE must first demonstrate compliance with the Environmental Protection Agency's (EPA) Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR Part 191) hereafter called the Standard. The Standard was vacated by a Federal Court of Appeals in 1987 and is undergoing revision; by agreement with the State of New Mexico the DOE will continue to evaluate repository performance with respect to the Standard as first promulgated until a new version is available. This paper reviews the results of a 1989 preliminary demonstration of the performance-assessment methodology that will be used by the WIPP project ultimately to assess compliance with the Standard. The report also describes conceptual and numerical improvements in the performance-assessment methodology made during 1990, and summarizes the progress made toward achieving the probabilistic assessment of repository performance required for regulatory compliance. 13 refs., 4 figs.