High heat tank safety issue resolution program plan

The purpose of this program plan is to provide a guide for selecting corrective actions that with mitigate and/or resolve the single-shell tank 241-C-106 high-heat tank safety issue. This program plan also outlines the steps necessary to implement corrective actions. The postulated hazard for the high-heat tank safety issue involves the release of nuclear waste to the environment as the result of heat-induced structural damage to the tank's concrete, should forced cooling be interrupted for extended periods. The heat generation originates from the radioactive decay of waste material (primarily [sup 90]Sr) that was inadvertently transferred into the tank in the late 1960s. Cooling to prevent waste temperatures in excess of the 300[degree]F operating limit is currently accomplished by evaporative cooling through active filtered altered ventilation. This is supported by periodic water additions to maintain a liquid cover over the sludge, and for enhanced thermal conductivity for heat transfer.