The evaluation of exploitable potential and quality of the underground
water used by «Zelenogradvodokanal» Operations Department

Summary

The results of studying the regimes of underground water levels and water abstraction from the service carbonaceous aquifers are presented. Beginning from 2003 the Kasimovskii and Podol’sko-Miachkovskii complexes have been exploited under pressure-gravity conditions; whereas the Aleksinsko-Protvinskii complex – under pressure conditions. Reappraisal of the exploitable underground water potential on the territory under consideration was carried out with mathematical model approach using software package. The analysis of the long-term studies showed that at present the water table is not changing along with the marked decline of the underground water level in the service aquifers. In the wells completed in different aquifer systems the change of the underground water level of the next to the surface aquifer system in the sections with jurassic aquitard clays in their geologic profile does not depend on carbonaceous system level behavior (therefore, on water abstraction). In case the next to the surface aquifer lies directly on a carbon aquifer system the exploitation of the latter can affect the underground water level. However, under the circumstances the natural depth of occurrence of the next to the surface aquifer system is usually more than 3–5 meters; therefore, any further level decrease does not have any negative consequences for vegetation. The analysis of artesian water quality for the period from 1981 to 2012 for 18 organoleptic and composite indices, and three microbiological parameters is presented. The comparative analysis of artesian water quality of three aquifers is given alongside with the composition consistency of aquifer systems. The concentration of the elements typical for aquifers is presented.

Key words

water intake , monitoring , sanitary protection zone , artesian water quality , aquifer system , underground water storage , bacteriological and chemical pollution

Groundwater of the Oryol region: hydrodynamic state and chemical composition

Summary

The specific features of two aquifer carbonate systems – the Voronezh-Livenskoe and Zadonsk-Optukhovsky, as well as their role in supplying groundwater to the Oryol region – are considered. Based on the methodological recommendations, groundwater monitoring is carried out under various conditions in the wells of the local observation network and in the wells of the state reference network. A brief description of the methodology for studying the quality of groundwater is given in order to monitor its condition to make the required solutions, if necessary. The dynamics of the development of three depression pits in the region and areas of groundwater pollution are analyzed, in the zone of influence of which drinking water intakes are located.

Key words

ground water , aquifer system , depression pit , polluted area

Natural specifics of underground water deposits of the intermorainic complex of the Kurortnyi district of Saint-Petersburg

Summary

The problems of estimating the resources of underground water under complicated hydrogeological conditions of the intermorainic water-bearing complex in the Kurortnyi district of Saint-Petersburg are brought up. The complexity of the deposit conditions lie in the irregularity of the lithological composition and capacity of the water-bearing material in relation to the depth and strike as well as in the determination of factors of formation and replenishment of the underground water deposits in the process of their exploitation. Such deposits, as a rule, are associated with the areas of ancient buried valleys and contain significant stocks of fresh underground water available for drinking purposes. In the Kurortnyi district «Molodezhnoe», «Zelenogorskoe», «Solnechnoe» deposits are located within the boundaries of the cognominal communities. The underground water resources amount to about 15–30 thousand m³/day, deep well flow rate – 2–5 thousand m³/day. Under the conditions of the complicated natural specifics of the deposits estimating the underground water resources by traditional methods of hydrodynamic calculations gives highly distorted results. The best-attested results are obtained during the development of a computational geofiltration model. The option of calculating underground water resources by the mathematical model method is considered. The principle stages of designing a computational geofiltration model through the example of «Molodezhnoe» deposit are given.

Key words

ground water , aquifer system , hydrogeologic conditions , water resources evaluation , geofiltration model , Gulf of Finland