Groundwater vulnerability assessment based on calculation of chloride travel time through the unsaturated zone on the area of the Upper Kama potassium salt deposit

Abstract Wastes of potash industry stored at the Earth’s surface in salt tailing piles and sludge storages are a source of salinization of groundwater and surface water. The groundwater vulnerability assessment estimated on the basis of calculation of chloride travel time through the unsaturated zone can be taken into account in the development of design solutions aimed at minimizing the damage to the geological environment when placing waste products. The study precisely defined the structure of the unsaturated zone of the Upper Kama salt deposit based on the geological columns data of about 400 wells, and underlined the role of infiltration recharge as one of the main factors of groundwater vulnerability with respect to pollutants coming from the ground surface. The research findings offer a new basis both for protective measures development against groundwater contamination and for further methodological research in the case of specific areas of the territory in a larger scale.