The Bureau of Land Management (BLM), US Department of the Interior has asked Sandia National Laboratories (SNL) to perform scientific studies relevant to technical issues that arise in the development of co-located resources of potash and petroleum in southeastern New Mexico in the Secretary’s Potash Area. The BLM manages resource development, issues permits and interacts with the State of New Mexico in the process of developing regulations, in an environment where many issues are disputed by industry stakeholders. The present report is a deliverable of the study of the potential for gas migration from a wellbore to a mine opening in the event of wellbore leakage, a risk scenario about which there is disagreement among stakeholders and little previous site specific analysis. One goal of this study was to develop a framework that required collaboratively developed inputs and analytical approaches in order to encourage stakeholder participation and to employ ranges of data values and scenarios. SNL presents here a description of a basic risk assessment (RA) framework that will fulfill the initial steps of meeting that goal. SNL used the gas migration problem to set up example conceptual models, parameter sets and computer models and as a foundation for future development of RA to support BLM resource development.
Over 25 years, scientists and engineers designed engineered features to complement attributes of the natural barrier of volcanic tuff at Yucca Mountain in southern Nevada such that a proposed repository in the unsaturated zone would safely isolate spent nuclear fuel and highlevel radioactive waste over 106 years. Initially in 1983, an engineered barrier design applicable to several geologic media was used. With the Congressional direction to characterize Yucca Mountain, the engineered design gradually adapted to conditions in unsaturated tuff in the 1990s. The repository switched from floor emplacement of waste in small, single-walled stainless steel canisters to in-drift emplacement in large, double-layered containers. By 2000, the outer layer was high-nickel alloy to resist corrosion and the inner layer was stainless steel for strength. To avoid localized corrosion during the ∼1000-yr thermal period, titanium drip shields were also added above the containers. By 2008, a modular design of the repository was used for flexibility. In general, flexibility in accommodating various waste forms has been an intended attribute of geologic disposal system designs, rather than tuning the disposal system to specific characteristics of waste durability. The degradation rate of the radioactive waste matrix was an important parameter of the source-term in early modeling analysis. However, by the mid 1990s, analyses used fairly rapid degradation rates within the oxygenated environment of the unsaturated zone. Other components of the multiple barrier disposal system compensated for high degradation rates.
The results described in this report are an analysis of nationwide surveys, administered between 2006 and 2015, which measure preferences of US residents concerning the environment and energy sources. The Energy & Environment (EE) survey series is conducted annually by the Center for Energy, Security & Society (CES&S), a joint research collaboration of the University of Oklahoma and Sandia National Laboratories. The annual EE survey series is designed to track evolving public views on nuclear materials management in the US. The 2015 wave of the Energy and Environment survey (EE15) was implemented using a web-based questionnaire, and was completed by 2,021 respondents using an Internet sample that matches the characteristics of the adult US population as estimated in the US Census. A special focus of the EE15 survey is how survey respondents understand and evaluate “consent” in the context of the storage and transportation of spent nuclear fuel (SNF). This report presents an overview of key results from analyses of questions related to consent-based siting and other elements of the nuclear energy fuel cycle.
This report presents a concise history in tabular form of events leading up to site identification in 1978, site selection in 1987, subsequent characterization, and ongoing analysis through 2009 of the performance of a repository for spent nuclear fuel and high - level radioactive waste at Yucca Mountain in southern Nevada. The tabulated events generally occurred in five periods: (1) commitment to mined geologic disposal and identification of sites; (2) site selection and analysis, based on regional geologic characterization through literature and analogous data; (3) feasibility analysis demonstrating calculation procedures and importance of system components, based on rough measures of performance using surface exploration, waste process knowledge, and general laboratory experiments; (4) suitability analysis demonstrating viability of disposal system, based on environment - specific laboratory experiments, in - situ experiments, and underground disposal system characterization; and (5) compliance analysis, based on completed site - specific characterization . The current sixth period beyond 2010 represents a new effort to set waste management policy in the United States. Because the relationship is important to understanding the evolution of the Yucca Mountain Project , the tabulation also shows the interaction between the policy realm and technical realm using four broad categories of events : (a) Regulatory requirements and related federal policy in laws and court decisions, (c) Presidential and agency directives, (c) technical milestones of implementing institutions, and (d) critiques of the Yucca Mountain Project and pertinent national and world events related to nuclear energy and radioactive waste. Preface The historical progression of technical milestones for the Yucca Mountain Project was originally developed for 10 journal articles in a special issue of Reliability Engineering System Safety on the performance assessment for the Yucca Mountain license application [1-10]. The listing of mile stones, a distinct feature of those articles, has been collected and tabulated here. A lthough a brief description is presented here (based on the summaries in the 10 journal articles), the emphasis remains on the tabulation because of its usefulness in providing a comprehensive but concise history of the Yucca Mountain Project. The tabulation presented here is more elaborate than originally presented in that many of the interactions that occurred between the technical realm and policy realm can be depicted in separate columns. The usefulness of the milestones table is due in part to L.A. Connolly, for editorial and reference support, and S.K. Best, Raytheon, and L. Mays, Sandia National Laboratories (SNL), for illustration support. Reviewers P.N. Swift, SNL, and K. Gupta, University of Oklahoma, helped improve the discussion. The historical perspective presented is that of the author and is not necessarily held by reviewers, Sandia National Laboratories , and the US Department of Energy. As a historic perspective, the author is reporting on the work of others; however, any interpretative error s of the documentation are those of the author alone. The characterization and modeling of the Yucca Mountain disposal system required numerous participants with expertise in many areas of science and technology, as evident from the extensive reference list. Their diligent efforts are generally acknowledged here and through the many references to their impressive work, but the 10 journal articles acknowledge by name many of the numerous participants that contributed to the Yucca Mountain Project .
The theme of the paper is that consolidated interim storage can provide an important integrating function between storage and disposal in the United States. Given the historical tension between consolidated interim storage and disposal in the United States, this paper articulates a rationale for consolidated interim storage. However, the paper concludes more effort could be expended on developing the societal aspects of the rationale, in addition to the technical and operational aspects of using consolidated interim storage.
The safe transport of spent nuclear fuel and high-level radioactive waste is an important aspect of the waste management system of the United States. The Nuclear Regulatory Commission (NRC) currently certifies spent nuclear fuel rail cask designs based primarily on numerical modeling of hypothetical accident conditions augmented with some small scale testing. However, NRC initiated a Package Performance Study (PPS) in 2001 to examine the response of full-scale rail casks in extreme transportation accidents. The objectives of PPS were to demonstrate the safety of transportation casks and to provide high-fidelity data for validating the modeling. Although work on the PPS eventually stopped, the Blue Ribbon Commission on America’s Nuclear Future recommended in 2012 that the test plans be re-examined. This recommendation was in recognition of substantial public feedback calling for a full-scale severe accident test of a rail cask to verify evaluations by NRC, which find that risk from the transport of spent fuel in certified casks is extremely low. This report, which serves as the re-assessment, provides a summary of the history of the PPS planning, identifies the objectives and technical issues that drove the scope of the PPS, and presents a possible path for moving forward in planning to conduct a full-scale cask test. Because full-scale testing is expensive, the value of such testing on public perceptions and public acceptance is important. Consequently, the path forward starts with a public perception component followed by two additional components: accident simulation and first responder training. The proposed path forward presents a series of study options with several points where the package performance study could be redirected if warranted.