Evaluation of the suitability of the WIPP site

Determination of the suitability of the site for WIPP is only the first major phase in the evaluation of the radiological impact of the repository on the public health and safety. The Environmental Evaluation Group (EEG) will continue to independently review the design of the facility, the operational procedures, the criteria for packaging and shipment of the waste, the plans, procedures and results of the WIPP experiments, emergency preparedness, adherence to EPA and pertinent NRC regulations, and other important features of the project. EEG has concluded from existing evidence that the Los Medanos site for the WIPP project has been characterized in sufficient detail to warrant confidence in the validation of the site for the permanent emplacement of approximately 6 million cubic feet of defense transuranic waste. This conclusion is based on the assumption that the maximum surface dose rate for the unshielded remote-handled transuranic waste canisters will be 100 rem/hr with a maximum radionuclide concentration of 23 Ci/liter. The Site and Preliminary Design Validation program, through the drilling of two shafts to the selected repository level at 2160 ft below the surface and excavation of about 9000 ft of tunnels, has confirmed the interpretations made about the subsurface geological conditions at the site. For an assessment of the potential radiation effects of the nuclear waste repository on the public health and safety, it is necessary to understand the regional geological and hydrological setting. Much work has been done to understand these conditions and to address several specific issues which have arisen as a result of such studies. However, it is almost inevitable that some questions remain unanswered at a given time in the decision-making process. EEG has identified work which still needs to be done at the Los Medanos site in order to improve confidence in the worst case scenario models of possible breaches of the repository