Scientific publications

This paper presents the results of hydrogeochemical studies in the Ruskeala Mining Park, created at a marble deposit in the Sortavala District (Karelia). It presents the isotope and geochemical characteristics of groundwater and surface waters in natural (Tohmajoki River, small lakes) and artificial (quarry reservoirs, a flooded adit) water bodies. The distribution and accumulation of trace elements, radioactive and radiogenic elements in water are analyzed. The process of marble quarry transformation into a reservoir is described, the main driver being the influx of atmospheric precipitation and groundwater, the chemical composition of which is altered within the workings depending on their size, degree of open-air exposure, and seasonality. The role of carbon dioxide in the seasonal variations of the water chemical composition in open water bodies is demonstrated. To establish the nature of the water-rock equilibrium and the vector of transformation of the solution’s composition over time, laboratory experiments were conducted for marble leaching with water, and the carbonate saturation of experimental and natural solutions was calculated. It has been shown that groundwater enters the quarry at near equilibrium with carbonates. The degree of saturation in quarry water varies across the year: in winter, minerals are soluble, while in summer, the water is oversaturated with carbonates, forming a suspended solid. Unlike groundwater, quarry waters contain elevated nitrate concentrations compared to background levels, which is associated with the growing recreational pressure on the Mining Park premises.