Characteristics of a simultaneous sampling system for the speciation of atmospheric T and C, and its application to surface and soil air

Amano, Hikaru; Koma, T.*; Atarashi-Andoh, Mariko; Koarashi, Jun; Iida, Takao*

Journal of Radioanalytical and Nuclear Chemistry, 252(2), p.353 - 357, 2002/00

https://doi.org/10.1023/A:1015782726049

no abstracts in English

Measures of closing report of outside waste storage pits separate volume part II; Data collections about measurement of contamination and measurement after decontamination in outside waste storage pits

; Sukegawa, Yasuhiro*; Suzuki, Satoshi*; Yoshida, Michihiro; ; *; Miyo, Hiroaki

JNC TN8440 2000-022, 180 Pages, 2000/10

JNC-TN8440-2000-022.pdf:12.16MB

At outside waste strage pits, containers for strage of wastes corroded and were flooded, and it was confirmed on August 26, 1997. Confirmation of contamination of the pits outskirts, installation of sheets to prevent rainwater from flowing into the pits, drawing stay water were executed, promptly. Design and authorization works of the work house and waste treatment devices to take out wastes of the pits were executed too. After construction of the work house, taking out wastes of the pits started, and finished on April 10, 1998. Investigations of the inflow point of rainwater and leak of stay water were executed next. The results were reported to Science and Technology Agency (STA), adjoining authorities on December 21, 1998. After decontamination of the pits inner walls to background level of the radioactivity which included general concrete, control area was removed, and the pits were closed by concrete. Measures of closing of the pits were prepared from the middle of August, 1999, and dismantlement of unnecessary instruments started. Decontamination of the pits started from the beginning of September, 1999. The above works finished on June 30, 2000. After decontamination of the pits, STA, adjoining authorities confirmed the dircumstances. Work pouring concrete into the pits was executed three times (three levels), and finished on August 31, 2000. In addition to above, the amount of concrete poured into the pits was about 1,200 m. These data compiled the inspection of contamination in measures of closing of the pits.

Measures of closing report of outside waste storage pits

; Ishibashi, Yuzo; Yoshida, Michihiro; Miyo, Hiroaki; Sukegawa, Yasuhiro*; *; Suzuki, Satoshi*

JNC TN8440 2000-020, 500 Pages, 2000/10

JNC-TN8440-2000-020.pdf:25.91MB

At outside waste storage pits, containers for storage of wastes corroded and were flooded, and it was confirmed on August 26, 1997. Confirmation of contamination of the pits outskirts, installation of sheets to prevent rainwater from flowing into the pits, drawing stay water were executed, promptly. Design and authorization works of the work house and waste treatment devices to take out wastes of the pits were executed too. After construction of the work house, taking out wastes of the pits started, and finished on April 10, 1998. Investigations of the inflow point of rainwater and leak of stay water were executed next. The results were reported to Science and Thechnology Agency (STA), adjoining authorities on December 21, 1998. After decontamination of the pits inner walls to background level of the radioactivity which included general concrete, control area was removed, and the pits were closed by concrete. Measures of closing of the pits were prepared from the middle of August, 1999, and dismantlement of unnecessary instruments started. Decontamination of the pits started from the begining of September, 1999. The above works finished on June 30, 2000. After decontamination of the pits, STA, adjoining authorities confirmed the circumstances. Work pouring concrete into the pits was executed three times (three levels), and finished on August 31, 2000. In addition t0 above, the amount of concrete poured into the pits was about 1,200 m.

None

; ; ; ; ; ;

PNC TN8440 98-025, 111 Pages, 1998/07

PNC-TN8440-98-025.pdf:11.06MB

None

Study on the environmental movements of Radon and its decay nuclides

PNC TJ1630 95-001, 29 Pages, 1995/03

PNC-TJ1630-95-001.pdf:1.63MB

None

Study on restricted use of contaminated debris on Fukushima Daiichi NPS site, 1; Estimation of reference radioactive concentration for recycling materials

Shimada, Taro; Miwa, Kazuji; Takeda, Seiji

no journal, , 

Rubbles less than 5Sv/h of surface dose rate, which are stored in the Fukushima Daiichi NPS (1F) site, will be recycled and applied in a restricted use only within 1F site in the future. In this study, we suggested a concept for establishing the reference radioactive concentration of recycling material for the restricted use in the 1F site, and then calculated the reference radiocesium concentrations of the recycling material used for paved roads and the bases of concrete building. In order to prevent the working time from being decreased, it is necessary for the restricted use to suppress the additional dose to a level of value. Therefore, focusing on the current background air dose rate in the 1F site, we suggested the required condition that air dose rate increased by use of contaminated recycling material instead of non-contaminated did not exceed the variation range of the background dose rate. In addition, to validate the restricted use under the reference concentration, following three items should be confirmed; (1) additional dose for worker using the recycling material does not exceed 2mSv/y, 10% of worker dose limit; (2) the impact to air dose rate evaluated at the 1F site boundary does not exceed the 1mSv/y including direct and skyshine radiations from wastes stored in the site; (3) the impact of migrated radionuclides into groundwater does not exceed the operational target value. The reference radiocesium concentrations for recycling aggregate taken from contaminated concrete rubbles were evaluated for paved road and bases of concrete building.