Contingency plan for the Old Hydrofracture Facility tanks sluicing project at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Lockheed Martin Energy Systems, Inc. (Energy Systems), plans to begin a sluicing (flushing) and pumping project to remove the contents from five inactive, underground storage tanks at the Old Hydrofracture Facility (OHF) at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The tank contents will be transferred to the Melton Valley Storage Tanks, which are part of the active waste treatment system at ORNL. The purpose of the project is to minimize the risk of leaking the highly radioactive material to the environment. The five OHF tanks each contain a layer of sludge and a layer of supernatant. Based on a sampling project undertaken in 1995, the sludge in the tanks has been characterized as transuranic and mixed waste and the supernatants have been characterized as mixed waste. The combined radioactivity of the contents of the five tanks is approximately 29,500 Ci. This contingency plan is based on the preliminary design for the project and describes a series of potential accident/release scenarios for the project. It outlines Energy Systems' preliminary plans for prevention, detection, and mitigation. Prevention/detection methods range from using doubly contained pipelines to alarmed sensors and automatic pump cutoff systems. Plans for mitigation range from pumping leaked fluids from the built-in tank drainage systems and cleaning up spilled liquids to personnel evacuation