The Impact of Ignalina Nuclear Power Plant Waste Water on Lake Drūkšiai Before the Decommissioning of the Plant (2007–2009)

Ignalina NPP (INPP) is located at Lake Druksiai utilized as cooler. Like Chernobyl NPP, INPP was equipped by RBMK–1500 type reactors. One unit was decommissioned in 2005, the other in 2009. The aim of this study was to evaluate activity concentration of radionuclide’s in bottom sediments and macrophytes from the waste water (WW) channels of the INPP as well as assess the phytotoxicity of water and bottom sediments of the WW channels and Lake Druksiai zones directly impacted by these WW. The significant decrease of activity concentration of radionuclide’s in bottom sediments of WW channels and Lake Druksiai after the Unit One decommissioning was determined. Phytotoxicity of water and bottom sediments of WW channels and Lake Druksiai also fluctuated in rather wide limits during 2007–2009. After the INPP decommissioning, chemical and radioactive pollution of the lake will persist during a long period of INPP dismantling works, consequently, the investigation of the radioecological and ecotoxicological state of the lake will be necessary.