On June 1, 2005, the Kola NPP units no. 2,3,4 were in operation. Plant load comprises 861 MW according to the dispatcher’s output-to-grid-limitations. On May 31, 2005 unit no.1 maintenance was finalized. The unit was under planned maintenance planned since April 28, in accordance with the annual repair schedule for 2005. According to unit no.1 start-up program all necessary hydraulic and safety system tests were performed. In line with the load schedule unit no.1 was put into cold shutdown mode.