Abstract
It was feared that heavy metals and acid water were drained from rock mucks generated by excavating the Hakouda Tunnel of the Tohoku Shinkansen railway because there are some mines around this tunnel. The rock mucks were evaluated about the dissolution features based on geochemical analysis and were disposed to controlled disposal sites if the rock mucks had possibility of heavy metals and/or acid water dissolution.
We studied the water-rock interaction at the sites based on the drainage water quality and the geochemical features of rock mucks. It is clear that the ratios of the major ion concentrations are explained by dissolution of pyrite and plagioclase contained in the rock mucks. On the other hand, because the heavy metals are included very little in the drainage water from the disposal sites, it is assumed that these elements are adsorbed to the rock mucks in the disposal site.
