抄録
Recently, the pollution of water and soil due to industrial or radioactive wastes has been discussed, and it becomes important to forecast the behavior of pollutants in environmental hydro-system, such as substratum layer near the coast of nuclear power plant site.
The degree of mobility of radionuclides can be represented by the apparent diffusion coefficients in a bottom layer.
So, these work presented a mathematical model with non-steady boundary condition which could determine this coefficients, and examined the validity of this model by laboratory experiments, where many long-lived radionuclides diffused into a sandy sediment.
The values of apparent diffusion coefficient were approximately obtained as follows,
(3-4)×10-7cm2/sec for Sr, (1-2)×10-7cm2/sec for Mn and (3-8)×10-8cm2/sec for Cd, Co and Zn.
The theoretical models for Ru, Ce, Hg and Zr were not suited for description of their behavior owing to the complex sorption model.
