FLOODING ASSESSMENT OF SALT MINING AREAS TO REDUCE THE THREAT OF TRANSBOUNDARY SPREAD OF SALINE POLLUTION

Abstract

The former mining of rock and potassium salt deposits in Transcarpathia and Nearcarpathia (western Ukraine) has a potential impact on water resources and the transboundary spread of saline pollution (e.g. Solotvyno rock salt deposit on the banks of the Tisza River on the Ukraine-Romania border; Kalush-Golyn potassium-magnesium salt deposit in the Dniester River basin). The threat of pollution spreading increases during floods, flash floods, and flooding. The aim of the study is to determine the extent of possible flooding based on the analysis of natural and man-made factors and using remote sensing data. The probabilistic, comparative-analytical and statistical methods, mechanical and mathematical bases of engineering geology in a complex with system analysis approaches were used in research. Geological, engineering-geological, hydrogeological and remote sensing data (Sentinel-1A) have been processed using a geoinformation system to the database of indicators of flooding processes. The territory is ranked according to the probability of flooding. The probability of flooding varies from 0.03 to 0.75 within the floodplain of Tisza river, 0.8-1.0 in places with a high groundwater level at settlement. The highlighted areas by GRD processing images (Sentinel-1A mission) according to the data of 2 flash floods indicate the probable places for flooding development in additional abnormal synoptic precipitation. The water mineralisation assessment on the flooding risk zones was based on the data of hydrological stations and wells for the Quaternary aquifer. The mapping shows that the flood zone includes areas of increased mineralisation (up to 13 g/l), but in the conditions of significant water inflow during a flood, the capture of such mineralisation would not lead to chloride concentration increase in the river after the flood. The developed schemes are proposed for use by municipal authorities in risk management programs.