An extent of the vulnerability of the free water exchange zone (FWEZ) from technogenic pollution sources has been studied. Its vulnerability from influence of the surface and underground pollution sources has been established. The degree of damage of FWEZ is characterized by appearance and expansion of the range of the chloride pollution in the process of exploration and in the early stage of the industrial operation. A prediction of the most probably development of technogenic impact on FWEZ has been formulated.