Odnawialność wód podziemnych zlewni prawobrzeżnej Warty, Górnej Noteci i Zgłowiączki w układzie hydrodynamicznym silnie zmienionym odwodnieniami kopalnianymi

The article presents the evaluation of groundwater renewability due to effective infiltration in the hydrological system of the right-bank basin of Warta, Górna Noteć and Zgłowiączka rivers which is remarkably affected by productive lignite open mines (drainage process) as well as two closed mines (ceased dewatering process). The evaluation has been done using stationary model for groundwater circulatory system with four aquifers basing on groundwater exploitation state in 2012. The forecast of groundwater exploitation process in the next 25 years based on unsteady model for planned periods when mines will be productive and then closed indicates that effective infiltration amount is significantly overestimated for water table depression areas in the regions of open lignite mines. This results in large groundwater level increase (above ground level) in model forecast which needs to be corrected by decreasing the estimated effective infiltration amount to the average value for adjacent areas. This ostensible increase in effective infiltration amount in steady state model is the result of free and elastic groundwater resources detraction and not an actual effective infiltration increase (which was assumed so far for productive open mines areas by Sawicki, 2000 and Szczepiński, 2013).