Scrutinizing Fukushima crisis

The government on Tuesday released a report on the accidents at Fukushima No.1 nuclear power plant. Submitted to the International Atomic Energy Agency, the report describes 28 lessons and countermeasures.

The government and the power industry should act quickly on recommendations derived from the report. The report, though, should not be used as an excuse to continue Japan’s relatively high dependency on nuclear power.

Showing that the Fukushima accidents are much more severe than generally believed, the report points to the possibility that “melt-through” incidents occurred at the Nos. 1, 2 and 3 reactors — with molten nuclear fuel passing through the bottom of the pressure vessels and collecting at the bottom of the containment vessels.

It says that the government should have disclosed data based on SPEEDI (System for Prediction of Environmental Emergency Dose Information) — which predicts the distribution of radioactive substances released by a nuclear accident — immediately after the Fukushima accidents happened. This amounts to an admission that the government for many days hid crucial data from affected local residents.

The report calls for separating the Nuclear and Industrial Safety Agency from the Ministry of Economy, Trade and Industry, which pushes nuclear power generation.

The government must ensure that an independent NISA will rigorously check the safety of nuclear power plants — free from the influence of the nuclear power establishment — and get rid of the bureaucratic inertia that hampers quick action.

The report calls for scrapping the current design approach of having multiple reactors share a common central control room and other important facilities, and of locating the pool for cooling spent nuclear fuel at a high place in a reactor building. This approach has demonstrated that the power industry made little of the possibility of severe accidents.

An official of Fukui Prefecture, where 13 commercial reactors are concentrated, said that further studies of the effects of earthquake tremors on the Fukushima No. 1 plant are needed and that the report fails to mention measures for old reactors. The government should heed his criticism.