Numerical modeling of the releases of (90)SR from Fukushima to the ocean: an evaluation of the source term.
A numerical model consisting of a 3D advection/diffusion equation, including uptake/release reactions between water and sediments described in a dynamic way, has been applied to simulate the marine releases of (90)Sr from the Fukushima power plant after the March 2011 tsunami. This is a relevant issue since (90)Sr releases are still occurring. The model used here had been successfully applied to simulate (137)Cs releases. Assuming that the temporal trend of (90)Sr releases was the same as for (137)Cs during the four months after the accident simulated here, the source term could be evaluated, resulting in a total release of 80 TBq of (90)Sr until the end of June, which is in the lower range of previous estimates. Computed vertical profiles of (90)Sr in the water column have been compared with measured ones. The (90)Sr inventories within the model domain have also been calculated for the water column and for bed sediments. Maximum dissolved inventory (obtained for April 10th, 2011) within the model domain results in about 58 TBq. Inventories in bed sediments are 3 orders of magnitude lower than in the water column due to the low reactivity of this radionuclide. (90)Sr/(137)Cs ratios in the ocean have also been calculated and compared with measured values, showing both spatial and temporal variations.
Dpt Física Aplicada I, ETSIA, Universidad de Sevilla , Ctra Utrera km 1, 41013 Sevilla, Spain.
R
R
Periáñez
Kyung-Suk
KS
Suh
Min
M
Byung-Il
N
N
Casacuberta
P
P
Masqué
D002588:Cesium Radioisotopes / Q000032:analysis; D003198:Computer Simulation; D062406:Fukushima Nuclear Accident; D019015:Geologic Sediments / Q000737:chemistry; D008962:Models, Theoretical; D009792:Oceans and Seas; D011834:Radiation Monitoring; D013326:Strontium Radioisotopes / Q000032:analysis*; D014875:Water Pollutants, Radioactive / Q000032:analysis*
D002588:Cesium Radioisotopes; D013326:Strontium Radioisotopes; D014875:Water Pollutants, Radioactive