[2M12-17] Bentonite

4:50 PM - 5:05 PM JST(7:50 AM - 8:05 AM UTC)

[2M17] Application of Bayesian statistics to the inspection of bentonite layers in radioactive waste disposal

*Ryo Nakabayashi¹, Yasutaka Watanabe¹, Shingo Yokoyama¹, Daisuke Sugiyama¹ (1. CRIEPI)

Keywords:

Radioactive waste disposal,Bentonite,Macroscopic permeability coefficient,Microscopic permeability coefficient,Bayesian statistics

Bentonite layers used as engineered barriers in radioactive waste disposal facilities are required to be low permeability. In this study, the authors proposed a method using Bayesian statistical analysis to reasonably determine the macroscopic permeability coefficient to determine compliance with the requirements for low permeability. The proposed method can quantify the uncertainty in the distribution of the microscopic permeability coefficient required to calculate the macroscopic permeability coefficient. By extracting the distribution of the microscopic permeability coefficient within this uncertainty and using it to determine compliance with the macroscopic permeability coefficient, a conservative decision can be reasonably implemented even with a small sample size.