INES-event
INES 1

Water leakages at Loviisa-1 NPP unit from the fuel loading pool on 17 and 18 August 2000 during the annual maintenance outage

At the Loviisa nuclear power plant unit 1 on the 17.8.2000 there was a water leakage from the fuel loading pool during the annual maintenance outage in connection to a test run of the fuel pool cooling system. Low activity water leaked from the pool into a room outside the containment due to a manual valve incorrectly set open. The volume of the leaked water was 20 m3. The leakage caused temporary doserate of 0.1 mSv/h outside the room door. There was no liquid or air release from the plant. Access to the contaminated area was restricted and the cleaning procedure was started.
The test was repeated on the 18.8.2000. In the reactor building a water leakage occurred again through a motor valve incorrectly open. The volume of the leaked water was this time 10 m3. The water was led into a water treatment system as planned for this kind of circumstances. The power plant is preparing cleaning procedures.
STUK has preliminarily classified the leakages as INES level 1 due to recurrence of events.

Location: LOVIISA-1
Event date: Thu, 17-08-2000
Nuclear event report
Legenda & explanation