Estimation of cenomanian-callovian groundwater complex of potable water vulnerability in Kyiv based on isotope-radiochemical data

Abstract

A present-day analysis of ground water conditions use by Kyiv population from well- water supply has been carried out. The results of investigation are directed to reveal the hydrogen radioactive isotope – tritium distribution regularity in the city wells.-rooms By means of geoinformational system ArcGIS the map-scheme of tritium distribution in cenomanian-callovian groundwater complex was constructed. It shows that isotope-radiochemical data can serve as an effective instrument to determine groundwater complex vulnerability to contamination.

One of the dominant sources of potable water supply in Kyiv is cenomanian-callovian groundwater complex. From the point of view of subsurface geology cenomanian-callovian groundwater complex is considered as covered on the right-bank of Dnieper river (apart from Obolon’) and as conditionally covered on the left-bank. With the aim to supply the city population with pure water the wide network of well-rooms has been installed since 1997; the number of well-rooms has been constantly growing. The water quality in well-rooms is controlled in order to reveal the exceeding boundary permissible concentrations corresponding to norm, however the present well-rooms water quality control has a local character and doesn’t allow to systematically estimate the ground water vulnerability to man-caused influence in area extent. The author has investigated hydrogen radioactive isotope – tritium distribution regularity in cenomanian-callovian groundwater complex as an indicator of ground water vulnerability to man-caused influence. The investigation results give grounds to assert that there is a danger of anthropogenic transformation of underground hydrosphere from the point of view of potable ground water quality changes towards it’s deterioration.