Evaluation of clearance level for radionuclides in asbestos-containing wastes

Shimada, Taro; Nemoto, Hiromi*; Takeda, Seiji

Hoken Butsuri (Internet), 57(1), p.5 - 29, 2022/03

https://doi.org/10.5453/jhps.57.5

Of the asbestos-containing wastes arising from the dismantling activities of nuclear facilities, those with radioactive concentrations that do not need to be treated as radioactive substances will be cleared from the nuclear regulatory control. Those will be disposed of or recycled as specially controlled industrial waste based on the Waste Management and Public Cleansing Act. The authors constructed evaluation scenarios according to the treatment manual for asbestos-containing waste and evaluated public exposure doses per year for 33 radionuclides. Based on the evaluated doses, the radioactive concentration corresponding to the dose criteria of 10 Sv/y for clearance was calculated for each radionuclide and scenario. As a result, the evaluated concentration was equal to or higher than the current clearance level. It was confirmed that the application of the current clearance level for asbestos-containing wastes did not affect safety.

None

Asaharam Shinya*

PNC TJ1064 98-002, 109 Pages, 1998/02

PNC-TJ1064-98-002.pdf:8.48MB

None

Development of ocean radiocesium distribution estimation system for recycling radiocesium-contaminated soil to coastal reclamation

Miwa, Kazuji; Takeda, Seiji; Iimoto, Takeshi*

no journal, , 

The Ministry of the Environment has indicated the policy of recycling the contaminated soil generated by decontamination activity after the Fukushima accident as material. By recycling to coastal reclamation which is one of effective recycling application, dissolved radiocesium and absorbed radiocesium on soil particles will flow out to the ocean by construction. It is suggested by previous studies that the both types of radionuclides affect concentration of radionuclides in marine organism. In safety assessment for the recycling, it is necessary to consider transition of nuclides in both types. Therefore, we developed a model to evaluate the radionuclides transition in the ocean considering the both types of radionuclides which flow out during constructing and operation. The concentration of radiocesium in ocean is estimated with time, and the impact of internal exposure dose by sea food ingestion is evaluated through comparison with other major exposure pathway.