Monitoring the quality of water from isolated marshes resulting from opencast and underground mining of the Sieniawa lignite deposit

The „Sieniawa” lignite mine is one of the oldest Polish mines extracting lignite by means of both underground and opencast mining. The latter process is carried out until the present day. The transformation of the landscape is the most visible evidence of carrying out mining activities and therefore systematic approach to the reclamation of brownfield sites is a very important element of the mine’s environmental policy. The authors present previous experiences and the course of reclamation of post-mining terrains created during the operation of the “Sieniawa” lignite mine. The greatest emphasis is placed on numerous small anthropogenic reservoirs formed as a result of spontaneous flooding due to underground exploitation (surface subsidence) and filling of open pits with water