Damage has been detected in the internal parts of the feedwater pumps located in the Olkiluoto 3 nuclear reactor, the facility's operator Teollisuuden Voima (TVO) announced on Wednesday.
Although the severity of the damage is not yet clear, it will likely have an effect on the reactor's trial operation and the start of regular electricity production, the firm said in a statement.
"We have now flagged this up and it needs to be sorted out. It may have an impact on the start of regular electricity production," TVO's Communications Manager Johanna Aho told Yle.
The damage was noticed during maintenance and inspection work, and the company said that the impact on the reactor's operating schedule will become clearer in the coming days. Olkiluoto 3 will be out of service until the damage is properly assessed and repaired.
The TVO statement also emphasised that the damage does not pose a risk to the safety of the nuclear power plant site.
"This has absolutely no impact on nuclear safety," Aho further confirmed to Yle.
The feedwater pumps in the turbine plant of a nuclear power plant pump water from the feedwater tank to the steam generators.
The Olkiluoto 3 project — which had initially been due to start full power electricity production in 2009 — has been besieged by problems and setbacks, including faulty components, safety tests, and even a lawsuit.
The 1.6-gigawatt OL3 will become Finland’s fifth and biggest reactor, and is expected to produce around 14 percent of the country’s electricity once it is fully operational, possibly by the end of this year.
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