INVESTIGATION OF THE INFLUENCE OF WATER USE OF THE POWER PLANT ON THE HYDROLOGICAL REGIME OF THE RIVER (ON THE EXAMPLE OF THE STYR RIVER)

Abstract

The purpose of this study was to investigated the hydrological mode of the Styr river waters in the area of influence of Rivne Nuclear Power Plant (RNPP) water use with the identification of factors that determine them and their interrelated impact. The approach based on the analysis of the range of variability (RVA) was used to assess changes in the hydrological parameters of the Styr river in the RNPP water intake and discharge area. The identified patterns and the analysis of the dynamics of RNPP water use indicate an increase in water consumption costs in the warm season, which is associated with higher ambient temperatures and, accordingly, greater evaporation of water from the cooling system. A positive, significant (p < 0,0001), strong (r = 0,7–0,9) correlation with R-sq = 0,9869 was found between the RNPP water intake and discharge regime and the river water temperature. The novelty of the work is to compare the actual water discharge of the Styr River in the RNPP water use area with the data of the normalised difference water index (NDWI) obtained using the Sentinel-2 satellite image of the Styr River. The practical significance of the study is that the results obtained from the study can be used to plan and implement appropriate water management strategies and focus on water quality and sources of pollution to prevent water pollution in water bodies and can be used to assess the non-radiological impact of discharges from nuclear power plants. The results of the study indicate that there is no impact of discharges from RNPPs, and therefore no improvement measures are required, since hydroecological indicators and changes in their values do not affect the ecological status of surface water bodies and do not impede the achievement of the Water Framework Directive objectives.