The current state of underground and superficial waters in the area of the liquidated mine <i>Mgachi</i> (Sakhalin Island, Russia)
The article is concerned with the hydrogeochemical peculiarities of the underground waters of the liquidated mine Mgachi. It has been found that the mine being flooded, technogenic (mine) waters were produced in the exhausted rock mass, which contain hydrocarbonates, sulfates, sodium, iron, mineral oil, zinc, manganese, copper, and chrome exceeding the limits of tolerance. The mineralisation of the mine waters varies between 2.062 and 4.71 g/L. The estimation of the effect the mine waters have on the surface water channels reveals that the flooded mine pollutes considerably the rivers Malyi Sertunai and Rozhdestvenka.