The paper considers the main factors determining the quality of underground water deposits within the RO, done hydrochemical and geoecological assessment of groundwater RO. The entropy of the groundwater ecosystem is calculated. It was found that most of the deposits have an entropy of less than 30%. that is, the water is clean enough, not experienced external influences. However, the water quality has deviations in individual indicators from the requirements of SanPiN 2.1.4.1074-01, which can be eliminated by conventional methods of water treatment.

Keywords: groundwater, hydrogeochemical heterogeneity, classification of groundwater, drinking water

The aim of this work is to study the degree of protection of underground waters of the Kuibyshev district of Rostov region. The study area represented by the geological deposits of Quaternary (recent sediments) Qh, Neogene and Paleogene systems (Oligocene) P3, Cretaceous (upper division) K2 and the Carboniferous system (upper, middle and lower portions) S1,2,3 based. On the analysis of geological structure of water-bearing rocks in the Kuibyshev district of the Rostov region, which showed an insufficient degree of protection of underground waters against pollution and, as a consequence, insufficient supply of public drinking water, built map of underground waters protection of the Kuibyshev district of the Rostov region

Keywords: groundwater, Geology, classification of water, pollution, drinking water, rural settlement