Fukushima operator feared shutdown if risks revealed

TEPCO ignored chance of big tsunami, 'fesses up to fear of regulation

The operator of the Fukushima Dai-Ichi nuclear power plant, TEPCO, has admitted it was ill-prepared to cope with the tsunami of March 2011, and promised to do better in future.

That promise is articulated in a new document, Fundamental Policy for the Reform of TEPCO Nuclear Power Organization (PDF), released last Friday.

The document makes for sobering reading, as TEPCO admits it had not paid a lot of attention to safety since 2002 and simply decided tsunamis of the scale that arrived last March would not be a problem because “... there were no watermarks or records of one.”

The report also says “There was no awareness that a tsunami exceeding site elevation would directly result in a severe accident.”

Nor was the plan prepared for a severe accident, with the report noting:

"Means for mitigating the impact after reactor core damage had not been prepared (preventing primary containment vessel damage, controlling hydrogen, preventing release of large amounts of radioactive materials into the environment, etc.)."

A powerful reason tsunami mitigation measures were ignored seems to have been fear that doing something would have alerted the world the precarious state of the plant.

In the document management admits it “Feared that if tsunami risk studies were disclosed that it would lead to immediate plant shutdown” and that “There were concerns of back-fitting operating reactors and litigation depending on the recent intention of the Nuclear Safety Commission to regulate severe accident measures.”

Another nasty from the report says:

“There was concern that if new severe accident measures were implemented, it could spread concern in the siting community that there is a problem with the safety of current plants.”

Management was also worried that putting in place would accelerate the anti-nuclear movement.

Elsewhere, the report details how staff simply didn't know what to do when the tsunami hit and unexpected failures occurred. Necessary supplies to mitigate the incident weren't at hand and were hard to procure, but staff weren't sure how to make them work when they did arrive and were, in any case, exhausted.

There's also an admission that:

“Sufficient preparations had not been made for cases where all power sources would be lost nor had there been adequate means provided for the subsequent response (cooling water injection, depressurization, low pressure water injection, heat removal, injection of cooling water into fuel pool, securing water sources, etc.). Workers were forced to respond while thinking about these issues on the spot.”

The release of the report is significant because it marks the first time TEPCO has admitted any culpability for the accident.

“As of three days ago TEPCO held to the position it was all the tsunami's fault,” Sydney University's Professor Bruce Armstrong told the Australasian Radiation Protection Society's conference in Sydney today. Armstrong described the accident as a “catastrophic failure” and said he is aware of predictions that between 100 and 1000 people will die of cancer because of the accident. ®

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