The Role of Rock in Chemical and Isotopic Composition of Groundwater in the Vicinity of Radioactive Waste Disposal Site

The research results of the hydrodynamic situation, as well as the chemical and isotopic compositions of target aquifers in the vicinity of radioactive waste storage are considered. The surpassing of water quality standards for Ra- 226, α-activity, Si, Fe, F, and some heavy metals was detected in target Upper Carboniferous aquifers. It was ascertained that the main reason for these changes was disturbance of hydrodynamic conditions as a result of withdrawal enhancement. Intensification of water-rock interactions caused the values of Ra-226 and α-activity to increase in target aquifers, because the main natural sources of Ra-226 are water-bearing rocks containing flints with natural radioactivity and overlying Jurassic layers containing phosphorite. Descending or ascending groundwater leakage caused contaminant incursion from the adjacent aquifers.