[en] This paper presents the methodology used to prepare a baseline risk evaluation of the bulk wastes at the quarry. The DOE is proposing to remove these bulk wastes and transport them approximately 6.4 km (4 mi) to a temporary storage facility at the chemical plant area of the Weldon Spring site. The DOE has responsibility for cleanup activities at the Weldon Spring site under its Surplus Facilities Management Program (SFMP). A baseline risk evaluation is an evaluation of the potential impacts on human health and the environment that may result from exposure to releases of contaminants from a site in the absence of site remediation. This evaluation is a key component of the remedial investigation (RI) process, as identified in guidance from the US Environmental Protection Agency (EPA) that addresses sites subject to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, as amended by the Superfund Amendments and Reauthorization Act of 1986. Response actions at the Weldon Spring quarry are subject to CERCLA requirements because the quarry is listed on the EPA's National Priorities List