The Hanford Nuclear Reservation located in Washington State once provided plutonium production and extraction facilities for the US weapons program. Radioactive waste from these production cycles was stored in large, carbon steel underground tanks. Across the Hanford reservation 177 tanks were constructed that hold waste, of which 28 were double-shell tanks (DSTs). Each DST is comprised of a primary tank wall to hold the slurry waste and an outer secondary liner. The space between the primary tank and secondary liner, denoted as the annulus region, has provided access for inspection equipment to interrogate the primary tank. Since the 1990s the DSTs have undergone an inspection program using conventional Ultrasonic testing (UT) techniques. Cost and time limitations, along with access restrictions, have prevented the entire primary tank wall from being examined. Inspections have prioritized a 1% portion of the primary tank wall of each DST. To supplement the UT program, the inspection is repeated every eight to ten years unless indications warrant a more frequent interval. Transmit-Receive, Electromagnetic Acoustic Transducer (TR-EMAT) technique was investigated to quickly and efficiently screen large areas [4]. This paper discusses the compensation mechanism and recommendations for applying the TR-EMAT screening technique to the tank integrity program.

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