Nondestructive measurement results of uranium-contaminated wastes using the passive method

Suzuki, Satoshi*; Komatsuzaki, Takashi*; Tadokoro, Hideaki*; Oki, Koichi

This report summarizes outline, methods and measurement results of actual wastes of nondestructive measurement system using the passive method applied to the evaluation of the quantity of uranium in the drum waste (0.2 m) and container waste (1 m). The following are the results. (1) The measurement number of drum wastes was 18,884 (4,703 of the number were pit wastes), at the end of March, 2011. (2) The measurement number of container wastes was 749 (110 of the number were pit wastes), at the end of March, 2011. (3) About 60% of drum wastes and about 80% of container wastes were metal and concrete. (4) 75% of drum wastes were less than detection limit, and average of radioactivity is 3.4 Bq (U-238)/g. Then 17% of container wastes were less than detection limit, and average of radioactivity is 2.3 Bq (U-238)/g. (5) If clearance level is 1.0 Bq (U-238)/g (IAEA RS-G-1.7), about 80% of wastes are below the clearance level.