GEOCHEMICAL AND ENVIRONMENTAL STATE OF GR OUNDWATERS IN RUSSIA - CAUSES AND TENDENCIES OF COMPOSITIONAL VARIATIONS OF GROUNDWATERS

Regional hydrochemical studies indicated that the formation of groundw aters with increased content of toxic monitored elements could not be considered only as a result of pollution by industrial, agriculture an d urbin wastes and products. The natural geochemical processes of grou ndwater formation also should be taken into account. As a result the r egional groundwater hydrogeochemical provinces are formed providing th e increased content of monitored elements. The quality of groundwater in recent hydrogeological conditions is considered as a result of coin cudent action of natural and technogenic processes creating formerly b eing not known absolutely new hydrogeochemical events.