Nuclear, Reactors

TEPCO: Fukushima nuclear reactor failure caused by tsunami, not earthquake

Tokyo Electric Power Co. says in a new report that the damage at Unit 1 of the Fukushima Daiichi nuclear power plant in Japan was caused by the impact of the tsunami and not coolant loss caused by the earthquake.

The report says Unit 1 survived the earthquake intact, and that the tsunami knocked out the backup diesel generators, which led to the failure of the cooling systems that caused the accident. The Fukushima Nuclear Accident Independent Investigation Commission of Japan’s Diet raised questions that the accident could have resulted from the loss of coolant caused by the earthquake, which would have contradicted previous reports that the reactor withstood the earthquake intact, according to NucNet.com.

Units 1, 2 and 3 all suffered reactor core, fuel and containment damage. Units 4, 5 and 6 were offline at the time of the accident, but Unit 4’s reactor building was damaged by a hydrogen explosion.

The report was less conclusive on why water injected into Units 1, 2 and 3 did not cool the reactor cores and prevent meltdown, the article said. It is possible the water seeped into other systems and did not reach the core. An investigation into the amount of water used is ongoing, the article said.

Click here to read the full report.

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