Historical background on performance assessment for the Waste Isolation Pilot Plant

Abstract

Protection Agency (EPA) certified that the WIPP dkposal system complied with its regulations. The EPA's decision was primarily based on the results from a performance. assessment conducted in 1996, which is summarized in thk special issue of Reliability Engineerhg and System Safety. This performance assessment was the culmination of four prelirninaryperformance assessments conducted between 1989 and 1992. "This paper provides a historical setting and context for how the performance of the deep geologic repository at the WIPP was analyzed.' Also included is background on political forces .acting on the project.Key Words: performance assessmen~probabilistic risk assessment risk assessment; radioactive waste disposal; Waste Isolation Pilot PlanG history . '1.0 IntroductionIn 1998,25 years 'after selection of the "Delaware Basin in southeastern New Mexico as a~otential disposal site for radioactive waste, the U.S. Environmental Protection Agency (EPA) certified that the Waste Isolation Pilot Plant (WIPP), an underground geologic disposal system, complied with its regulations. This paper presents a historical summary of the system characterization, engineering analyses, and scientific investigations undertaken by the WIPP Project over the past 25 years and provides a context for the~esults presented in this special issue of Reliability Engineering and System Safety. Although it is mot .essentird to know the WIPP'S history to comprehend the engineering analysis, an understanding of the issues that the project faced can be helpful. Many paths were followed during these 25 years to discern which phenomena were important at the WIPP, and often these paths were initiated in Tesponse to evolving notions of what kind of :g@tific information was "significant, what level of understanding was required, and how society could use this scientific information to decide whether deep geologic disposal of nuclear waste was acceptable.1-3/9/99 Draft \. DISCLAIMERPortions of this document may be illegible in electronic image products. Images are produced from the best available original document... .- Characterization of WIPP Disposal SystemThe choice of New Mexico as a potential disposal site for nuclear waste in 1973 (Claibome and Gera, 1974) was one in a series of episodes in which New Mexico had figured prominently with regard to nuclear phenomena. In 1942, the Manhattan Engineering Dkrnct selected New Mexico as the location (including what are known now asLos Alamos National Laboratory and Sandia National Laboratories) for assembling the scientists, engineers, and technicians who would develop the fist atomic bomb. As a direct consequence of that development, the first atomic explosion took place in 1945 in the desert near Alamogordo, New Mexico (Serber, 1992). Sixteen years later, in 1961, scientists with the Gnome Project detonated a device in the Delaware Basin in bedded salt near Carlsbad, New Mexico, as part of the Plowshare Program, which was exploring nonmilitary uses of nuclear explosives (Gard, 1968).After a potential...

End of FY10 report - used fuel disposition technical bases and lessons learned : legal and regulatory framework for high-level waste disposition in the United States.

“…Later sections discuss the standard of proof for compliance and retrievablity. 40 CFR 191 (198540 CFR 191 ( , 1993 50 FR 38066;58 FR 66398 Certify TRU disposal WIPP 40 CFR 194-EPA implementation criteria (1996) 61 FR 5224 Letter notice for formal review (1997) Rechard 2000 Compliance certification (1998) 63 …”

“…Quoting from the Historical Background on Performance Assessment for the Waste Isolation Pilot Plant and as summarized in Appendix B: Rechard 2000 With the encouragement of Carlsbad's politicians and citizens, and the tacit approval of New Mexico's governor Bruce King, ORNL [Oak Ridge National Laboratory] examined a portion of the Permian Basin called the Delaware Basin in southeastern New Mexico in the early 1970s for a suitable disposal site for nuclear waste. The area was semi-arid with little potable water and no significant, highly permeable aquifers near the surface.…”

“…Although the YMP timeline of events is new, the WIPP timeline and much of text related to WIPP is similar to previously published work. Rechard 2000 …”

“…NAS reaffirmed that position in 1961and 1970(NAS, 1970. Rechard 2000 Positive attributes for salt disposal include: (1) salt is easily mined, (2) salt has high thermal conductivity, (3) salt is plastic (readily deforms and flows), (4) salt fractures self heal, (5) salt has very low permeability and porosity, (6) salt has existed underground for millions of years, (7) salt deposits are often in stable tectonic regions, (8) salt deposits exist in many locations with wide geographic distribution in the US. With these positive attributes and technology available in the 1950 and 1960s, the AEC gave mined disposal in salt high priority, especially for defense-related radioactive waste, and selected a site for a repository in an existing mine near Lyons, KS in 1970.…”

“…Quoting from the Historical Background on Performance Assessment for the Waste Isolation Pilot Plant: Rechard 2000 …Under consideration were three kinds of waste-TRU waste, high-level waste from reprocessing spent nuclear fuel, and direct disposal of spent nuclear fuel-and whether the waste originated from defense or commercial activities. The initial focus of the AEC in the 1950s and 1960s with regard to disposal was on nuclear waste from reprocessing spent nuclear fuel (or high-level waste as it came to be called), because uranium was thought to be in such short supply that it would be necessary to recycle commercial fuel.…”