Drainage in Ikeshima Coal Mine

Abstract

Ikeshima Coal Mine was closed November 29, 2001, after 42 years of operation. The mining area was in the southwest of Ikeshima Island. The drainage increased as the mining areas extended, creating problems in both production operation and safety. The waters of drainage and flood in the mine have characteristics that (1) the rate of drainage decreases, (2) the chemical components of the waters in the floods do not change much with time but (3) they differ locally. The results of the investigation show that (1) the drainages in this mine are classified into 3 types by the combination of dissolved ions, (2) water eruption decreases exponentially, and (3) the southwest area of Ikeshima Island, the western area of the main drifts, is estimated to have huge water bearing areas.