Geologic investigations of the WIPP site: overview and issues

The Waste Isolation Pilot Plant (WIPP) is planned for the disposal of radioactive defense waste in bedded salt of southeastern New Mexico. Since 1975, the geologic investigations have progressed through preliminary site selection and geologic characterization phases; we are now primarily concerned with the long-term geological processes that may affect the site. These processes are grouped by hydrology, dissolution, geochemical, tectonic, and climatic mechanisms. Issues regarding isolation at the WIPP are usually grouped according to these processes or human intrusion. Combinations of human and water intrusion are the most likely ways of releasing radioactivity from the WIPP to the biosphere. The issues thus raised concern how well the hydrology is or must be known, whether resources will attract unacceptable human intrusion, and how geologic processes may enhance release of radionuclides. Analysis of these processes so far does not indicate that radioactive material will be released from the repository in significant amounts. The main issue (what are the consequences of the WIPP to the biosphere.) is satisfied, therefore, in spite of the possibility that unusual events, such as human intrusion, can occur