TOKYO (AP) – The operator of the destroyed Fukushima nuclear power plant said on Monday that two seismometers in one of its three molten reactors had been damaged since last year and had not collected data when a powerful earthquake hit the area earlier this month.
The recognition raised new questions about whether the company’s risk management has improved since a major earthquake and tsunami in 2011 destroyed much of the plant.
The defective seismometers emerged during a meeting of the Nuclear Regulatory Authority on Monday to discuss further damage to the plant resulting from a 7.3 magnitude earthquake that hit the region on February 13. Cooling water and pressure levels have dropped in reactors at Units 1 and 3, indicating additional damage to their primary containment chambers.
The operator, Tokyo Electric Power Co., has been repeatedly criticized for cover-ups and delayed disclosures of problems at the plant.
Regulatory officials asked TEPCO at the meeting why there was no seismological data from the Unit 3 reactor for Saturday’s earthquake, and concessionaire officials acknowledged that both seismometers failed – one in July and the other in October – and were never repaired.
TEPCO also said that seismometers, except for two of the reactor buildings that survived the 2011 disaster, were submerged by the tsunami water and were never replaced.
During Monday’s meeting, regulators said they were concerned about falling water and pressure levels in Units 1 and 3 primary containment chambers due to the possibility that the earthquake had expanded existing damage or opened up new leakage paths. , and urged the company to closely check for high levels of radiation in the groundwater around the reactor buildings.
TEPCO said that no abnormalities have been detected in the water samples so far.
Further damage can further complicate the plant’s already difficult decommissioning process and increase the large amounts of contaminated water stored at the plant.
Since the 2011 disaster, cooling water has been constantly escaping from damaged primary containment vessels into the basements of reactor and turbine buildings, where the volume increases as groundwater seeps through. The water is pumped and treated, then part of it is reused as cooling water, while the rest is stored in about 1,000 tanks.
TEPCO initially reported that there was no abnormality in the plant due to Saturday’s earthquake. But on Monday, he said about 20 of the tanks had slipped slightly due to the earthquake, a storage container with tilted radioactive waste and the asphalt pavement of the plant was cracked.