Nuclear

TEPCO Admits Delays in Announcing Meltdowns in Fukushima Nuclear Reactors

Tokyo Electric Power Co. (TEPCO) said it found a guideline in its operational manual that would have allowed it to declare nuclear meltdowns within days instead of the two months that it took.

Tokyo Electric Power Co. (TEPCO) said it found a guideline in its operational manual that would have allowed it to declare nuclear meltdowns within days instead of the two months that it took.
 
In the days following the nuclear disaster at the Fukushima Daiichi nuclear power plant in March 2011, TEPCO said there was “core damage” at units 1, 2 and 3 but did not admit they had melted down until May 2011, according to the Asahi Shimbun. Based on its nuclear disaster countermeasures manual, which was revised less than a year before the accident, TEPCO could have declared meltdowns at the three reactors in the days following the accident. The guideline says that the company should declare a meltdown when damage to the reactor core exceeds 5 percent.
 
The company had maintained that the reactors suffered core damage rather than meltdowns. In May 2011, TEPCO confirmed that Unit 3 had damage to 30 percent of its core and Unit 1 had damage to 55 percent of its core. Unit 2 suffered 35 percent of damage to the core.
 
TEPCO said the delay in announcements was caused by the lack of a basis to assess meltdowns in the wake of an accident, the article said. The revised standard was found during an in-house investigation into the utility’s response to the Fukushima accident.
 
“We sincerely apologize for failing to confirm the presence of the guideline in the manual for five years,” a TEPCO spokesperson was quoted as saying.
 
An internal investigation is underway.
 
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