Application of archaeological analogues for a repository safety case; Arguments supporting the waste container lifetime

Yoshikawa, Hideki; Ueno, Kenichi; Yui, Mikazu

Using X-ray computer tomography (X-CT), about 40 samples of archaeological irons, which were found at some Japanese ancient monuments with being buried underground for a few hundred to one thousand years, were analyzed for their corrosion depth to investigate long-term stability. The measured corrosion depths are more than one order of magnitude less than the design allowance of 40 mm, which supports that the designed corrosion allowance for an overpack is sufficiently conservative. Such archaeological study can provide useful evidences for long-term lifetime of a waste container which is an important element for making a robust safety case.