30 Août 2013
August 30, 2013
NRA: Quake did not damage coolant pipes
Japan's nuclear regulator has answered a question concerning the 2011 Fukushima Daiichi meltdown disaster: whether a reactor coolant system was damaged by the March 11th earthquake before the massive tsunami struck the plant.
The Nuclear Regulation Authority compiled a draft investigative report on the disaster in a meeting on Friday. Discussions focused on an unexplained puddle of water spotted by plant personnel on the 4th floor of the facility's No.1 reactor soon after the quake.
A Diet panel had said the water could have leaked from the reactor's coolant system due to quake damage. But the report says the water came from an upper-floor fuel pool that overflowed in the quake.
The report says the conclusion was reached when witness accounts matched results of an analysis of how water from the pool may flow. It also says damage to the coolant system would have caused leakage of steam, not liquid water.
Experts at the meeting did not object to the conclusion. But one said ruling out damage to the system without checking its pipes in detail may be premature. Another said the regulator should draw lessons from its inquiry to improve nuclear safety rules.
Commissioner Toyoshi Fuketa indicated that the authority will continue to look into the impact of the quake on the system.