Improved Ex-Tank Leak Detection and Monitoring Technology Demonstrations in Support of Single-Shell Tank Waste Retrieval at the Hanford Site in Richland, Washington

摘要

Led by the United States Department of Energy Office of River Protection (DOE-ORP) and CH2M HILL Hanford Group, Inc. (CHG), a team of experts from other facilities have been working together to narrow the field of new external tank leak detection technologies. The ability to detect and assess potential leaks more quickly will help reduce potential risks to public health and the environment during efforts to retrieve millions of gallons of waste from Hanford's older single-shell tanks (SST's). A method for early and reliable detection of leaks around and below the entire 75-foot diameter bottom of a SST is needed. 'Proof-of-concept' testing of six ex-tank leak detection and monitoring technologies was conducted at Hanford's 105-A Mock Tank Site in August 2001. A workshop was conducted in January, 2002 to review the results and select the best of the methods tested for further testing and demonstration in support of an SST retrieval. Three methods were selected: High Resolution Resistivity; Electrical Resistance Tomography--Long Electrodes; and Electrical Resistance Tomography--Point Electrode Arrays. Planned development activity includes performance evaluation tests to determine probability of detection and the probability of false alarm for each technology and deployability tests in an actual Hanford tank farm environment.