Guidance from the U.S. Department of Energy (DOE) for the performance of accident analysis in support of environmental impact assessments calls for a graded approach that considers frequencies as well as consequences of accidents, focuses on high-risk scenarios, and avoids bounding analyses that can obfuscate comparisons of alternative actions. This guidance reflects the fact that at the heart of an environmental impact statement is a comparative analysis of alternatives, including the proposed action; this analysis should address the environmental impacts in proportion to their potential significance, avoid addressing insignificant impacts in detail, and focus analysis resources to be as cost-effective as possible. Accordingly, a probabilistic risk analysis-based methodology to satisfy DOE guidance was developed and implemented for the DOE Waste Management Programmatic Environmental Impact Statement (WM PEIS). The methods are described and illustrated, and an outline of the computational framework is presented. This methodology, although developed for the WM PEIS, is, of course, applicable to general safety analyses. The implementation of the methods for the WM PEIS is summarized, and the extension of the methods to site-specific applications is explained.