Operation of Finnish nuclear power plants. Quarterly report, 1st quarter, 1995

Finnish nuclear power plant units were in power operation in the first quarter of 1995, except for two shutdowns at Loviisa 2, and shutdowns at both TVO units. The load factor average of all four plant units was 93.9%. The following events during the first quarter of 1995 were classified level 1 on the International Nuclear Event Scale (INES): At Loviisa 1, one of two isolation valves in the nuclear fuel storage pool cooling system pipeline were found to have been leaking since the 1994 annual maintenance outage. Impurities were observed in certain fuel bundles at Loviisa 2, resulting in abnormally increased coolant outlet temperatures in the bundles in question. In January, frazil ice accumulating in the filters of TVO I's cooling water screening plant caused the plant unit's shutdown by its automation systems. During back-up diesel loading tests at TVO plant units in February it was snowing heavily and the air intake channel filters of the diesels were blocked by snow. Other events in this annual quarter were classified level 0 on the INES. Occupational doses and radioactive releases off-site were below authorized limits. (5 figs., 5 tabs.)