scholarly journals Air dose rates and cesium-137 in urban areas—deposition, migration, and time dependencies after nuclear power plant accidents

2021 ◽  
pp. 1-9
Author(s):  
Kazuya Yoshimura
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Urban Areas ◽  
Nuclear Power ◽  
Dose Rates ◽  
Cesium 137 ◽  
Time Dependencies

MEASURES AGAINST RADIOACTIVE CONTAMINATION DUE TO FUKUSHIMA FIRST NUCLEAR POWER PLANT ACCIDENTS PART II: MEASUREMENT OF SPACE RADIATION DOSE RATES AND EXAMINATION OF CONTAMINATION IN FOOD

2012 ◽  
Vol 22 (01n02) ◽  
pp. 7-12 ◽  
Author(s):  
K. ISHII ◽  
A. TERAKAWA ◽  
S. MATSUYAMA ◽  
A. HASEGAWA ◽  
K. NAGAKUBO ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Radiation Dose ◽  
Radioactive Contamination ◽  
Nuclear Power ◽  
Space Radiation ◽  
Dose Rates ◽  
Miyagi Prefecture ◽  
Time Dependencies ◽  
Almost All

The space radiation dose rates at several points in Miyagi prefecture and their time dependencies were measured. Radiation exposure was mainly caused by 131 I at the earlier stage of Fukushima first nuclear power accidents and then by 134 Cs and 137 Cs . We inspected radioactive contamination for food produced in Miyagi prefecture and Fukushima city. As the result, almost all food were safe.

scholarly journals Unexpected source of Fukushima-derived radiocesium to the coastal ocean of Japan

2017 ◽  
Vol 114 (42) ◽  
pp. 11092-11096 ◽  
Author(s):  
Virginie Sanial ◽  
Ken O. Buesseler ◽  
Matthew A. Charette ◽  
Seiya Nagao
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Coastal Ocean ◽  
Public Health Issue ◽  
Fluid Exchange ◽  
Radium Isotopes ◽  
Cesium 137 ◽  
Plant Monitoring ◽  
Beach Sands

There are 440 operational nuclear reactors in the world, with approximately one-half situated along the coastline. This includes the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), which experienced multiple reactor meltdowns in March 2011 followed by the release of radioactivity to the marine environment. While surface inputs to the ocean via atmospheric deposition and rivers are usually well monitored after a nuclear accident, no study has focused on subterranean pathways. During our study period, we found the highest cesium-137 (137Cs) levels (up to 23,000 Bq⋅m−3) outside of the FDNPP site not in the ocean, rivers, or potable groundwater, but in groundwater beneath sand beaches over tens of kilometers away from the FDNPP. Here, we present evidence of a previously unknown, ongoing source of Fukushima-derived 137Cs to the coastal ocean. We postulate that these beach sands were contaminated in 2011 through wave- and tide-driven exchange and sorption of highly radioactive Cs from seawater. Subsequent desorption of 137Cs and fluid exchange from the beach sands was quantified using naturally occurring radium isotopes. This estimated ocean 137Cs source (0.6 TBq⋅y−1) is of similar magnitude as the ongoing releases of 137Cs from the FDNPP site for 2013–2016, as well as the input of Fukushima-derived dissolved 137Cs via rivers. Although this ongoing source is not at present a public health issue for Japan, the release of Cs of this type and scale needs to be considered in nuclear power plant monitoring and scenarios involving future accidents.

scholarly journals Radiation dose rates now and in the future for residents neighboring restricted areas of the Fukushima Daiichi Nuclear Power Plant

2014 ◽  
Vol 111 (10) ◽  
pp. E914-E923 ◽  
Author(s):  
Kouji H. Harada ◽  
Tamon Niisoe ◽  
Mie Imanaka ◽  
Tomoyuki Takahashi ◽  
Katsumi Amako ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Radiation Dose ◽  
Radiation Exposure ◽  
Dose Rate ◽  
Nuclear Power ◽  
Solid Cancer ◽  
External Dose ◽  
Dose Rates ◽  
Fukushima Daiichi

Radiation dose rates were evaluated in three areas neighboring a restricted area within a 20- to 50-km radius of the Fukushima Daiichi Nuclear Power Plant in August–September 2012 and projected to 2022 and 2062. Study participants wore personal dosimeters measuring external dose equivalents, almost entirely from deposited radionuclides (groundshine). External dose rate equivalents owing to the accident averaged 1.03, 2.75, and 1.66 mSv/y in the village of Kawauchi, the Tamano area of Soma, and the Haramachi area of Minamisoma, respectively. Internal dose rates estimated from dietary intake of radiocesium averaged 0.0058, 0.019, and 0.0088 mSv/y in Kawauchi, Tamano, and Haramachi, respectively. Dose rates from inhalation of resuspended radiocesium were lower than 0.001 mSv/y. In 2012, the average annual doses from radiocesium were close to the average background radiation exposure (2 mSv/y) in Japan. Accounting only for the physical decay of radiocesium, mean annual dose rates in 2022 were estimated as 0.31, 0.87, and 0.53 mSv/y in Kawauchi, Tamano, and Haramachi, respectively. The simple and conservative estimates are comparable with variations in the background dose, and unlikely to exceed the ordinary permissible dose rate (1 mSv/y) for the majority of the Fukushima population. Health risk assessment indicates that post-2012 doses will increase lifetime solid cancer, leukemia, and breast cancer incidences by 1.06%, 0.03% and 0.28% respectively, in Tamano. This assessment was derived from short-term observation with uncertainties and did not evaluate the first-year dose and radioiodine exposure. Nevertheless, this estimate provides perspective on the long-term radiation exposure levels in the three regions.

Analysis of the HI-TRAC VW Transfer Cask Dose Rates for Spent Fuel Assemblies Loaded in Nuclear Power Plant Krsko Storage Campaign One

2021 ◽  
Author(s):  
Davor Grgic ◽  
Mario Matijevic ◽  
Paulina Duckic ◽  
Radomir Jecmenica
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Variance Reduction ◽  
Spent Fuel ◽  
Dose Rates ◽  
Dry Storage ◽  
Fuel Assemblies ◽  
Spent Fuel Pool ◽  
The Impact

Abstract In this paper shielding analysis was performed to determine neutron and gamma dose rates around the transfer cask HI-TRAC VW loaded with Spent Fuel Assemblies (SFA) from Nuclear Power Plant (NPP) Krsko Spent Fuel Dry Storage (SFDS) Campaign one. The HI-TRAC VW is a multi-layered cylindrical vessel designed to accept a Multi Purpose Canister (MPC) during loading, unloading and transfer to dry storage building. The MPC can contain up to 37 spent fuel assemblies. The analysis was divided into two steps. The first step was the source term generation using ORIGEN-S module of the SCALE code package. The source was calculated based on the operating history of spent fuel assemblies currently located in the NPP Krsko spent fuel pool. The obtained particle intensities and source spectra of the SFA were used in the second step to calculate the dose rates around the transfer cask. A comprehensive hybrid shielding analysis included the calculation of dose rates resulting from fuel neutrons and gammas, neutron induced gammas (n-g reaction), and hardware activation gammas under normal conditions and during accident scenario. To obtain the dose rates within the acceptable uncertainties, FW-CADIS variance reduction scheme, as implemented in ADVANTG code, was adopted for accelerating final MCNP6 calculations. The dose rates around HI-TRAC VW cask were calculated using MCNP6 code for all 16 casks loading belonging to Campaign one in order to illustrate the impact of fuel assembly selection schemes proposed by company responsible for project realization (Holtec International).

scholarly journals Continuing <sup>137</sup> Cs release to the sea from the Fukushima Dai-ichi Nuclear Power Plant through 2012

2013 ◽  
Vol 10 (9) ◽  
pp. 6107-6113 ◽  
Author(s):  
J. Kanda
Keyword(s):  
Exchange Rate ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Water Exchange ◽  
Water Release ◽  
Power Company ◽  
Cesium 137 ◽  
Harbour Water ◽  
Surrounding Seawater

Abstract. The rate of cesium-137 (137Cs) release to the sea from the Fukushima Dai-ichi Nuclear Power Plant for the period until September 2012 was estimated. Publicly released data on 137Cs radioactivity in seawater near the power plant by Tokyo Electric Power Company strongly suggest a continuing release of radionuclides to the sea. The plant has an artificial harbour facility, and the exchange rate of harbour water with surrounding seawater was estimated by the decrease in radioactivity immediately after an intense radioactive water release. The estimated exchange rate of water in the harbour was 0.44 d−1 during the period from 6 to 19 April. The 137Cs radioactivity in the harbour water was substantially higher than that of seawater outside and remained relatively stable after June 2011. A quasi-steady state was assumed with continuous water exchange, and the average release rate of 137Cs was estimated to be 93 GBq d−1 in summer 2011 and 8.1 GBq d−1 in summer 2012.

Sign in / Sign up

Export Citation Format

Share Document