Clearance of concrete generated from modification activities of JRR-3; Results for measuring and evaluating radioactivity concentration

Ogoshi, Yurie; Satoyama, Tomonori; Kishimoto, Katsumi; Nanri, Tomohiro; Suzuki, Takeshi; Tomioka, Osamu; Takaizumi, Hirohide*; Kanno, Tomoyuki*; Maruyama, Tatsuya*

JAEA-Technology 2017-017, 152 Pages, 2017/08

JAEA-Technology-2017-017.pdf:15.97MB

At Nuclear Science Research Institute, clearance works for about 4,000 tons of extremely low-level radioactive concrete debris, which were generated from the modification activities of JRR-3 from FY 1985 to FY 1989 and stored in the waste storage facility NL, carried out. First of this clearance works, method for measuring and evaluating radioactivity concentration was approved by Minister of MEXT on July 25, 2008. And then, clearance works were started from FY 2009. Measuring and evaluating radioactivity concentration was achieved by using the approved method, and was confirmed by government. And then, clearance works were completed in FY 2014. The clearance concrete was recycled as a material for restoration works of the 2011 off the Pacific coast of Tohoku Earthquake. This report summarizes the results of measuring and evaluating radioactivity concentration, achievement of confirmation by government, recycling of cleared concrete and cost for clearance works.

Clearance of concrete debris generated from modification work of JRR-3, 4; Progress of clearance work

Satoyama, Tomonori; Kishimoto, Katsumi; Nanri, Tomohiro; Takaizumi, Hirohide; Kanno, Tomoyuki; Maruyama, Tatsuya; Yoshimori, Michiro

no journal, , 

no abstracts in English

Effective utilization of concrete debris generated from nuclear reactors; Clearance of concrete debris generated from modification work of JRR-3

Kishimoto, Katsumi; Satoyama, Tomonori; Takaizumi, Hirohide; Kanno, Tomoyuki; Maruyama, Tatsuya; Yoshimori, Michiro

no journal, , 

We have been storing about 4000 tons of very low-level radioactive concrete debris as radioactive wastes generated from the modification of JRR-3 between 1985 and 1990. At that time, the clearance system was not a part of our regulatory law. We conducted a preliminary survey of contamination levels, and then established procedures for measuring and evaluating the radioactivity concentration. In 2008, the government authorized our procedures for clearance. Since FY 2009, we have measured the radioactivity concentration of concrete debris, using the government-authorized procedures. By the end of FY 2012, the government had confirmed the correctness of our measurements and evaluation results on about 1900 tons of concrete debris. We processed the concrete debris that was approved by the government for recycling. By the end of FY 2012, we had reused about 600 tons of concrete debris as backfilling material in depressed areas around buildings in the Nuclear Science Research Institute.