16 Mars 2012
TOKYO (Kyodo) -- The Nuclear and Industrial Safety Agency proposed freezing studies started by the Nuclear Safety Commission in 2006 to expand the disaster mitigation zone around nuclear power plants in the event of a disaster, to bring Japanese regulations into compliance with international standards, according to emails released Thursday by the commission.
The agency, under the Ministry of Economy, Trade and Industry, argued that expansion of the zones ''could cause social unrest and increase popular anxiety,'' the emails showed.
The commission, an independent body supervising nuclear safety regulation, did not enlarge the zones after considering the matter in 2006. It now appears the outcome was a result of the agency's repeated complaints.
But if the commission had gone through with the expansion, the chaotic developments surrounding the evacuation of people following the nuclear crisis at the Fukushima Daiichi power plant in March last year might have been mitigated, people familiar with the matter said.
In March 2006, an expert panel at the commission began studying whether to expand the range of the priority disaster mitigation zone from the current radius of between 8 and 10 kilometers from a nuclear power plant, according to the emails.
While the current zone was set based on Japanese standards, new guidelines announced by the International Atomic Energy Agency called for the area within a radius of 5 km as the top priority zone and 30 km as the priority zone.
But the Nuclear and Industrial Safety Agency began to complain about the move in late April that year. In an email on April 24, for example, the agency asked the commission not to use the expression ''immediate evacuation'' for the top priority zone, and two days later asked it to freeze the studies.
Although the commission initially turned down the agency's repeated complaints, it eventually decided in November not to expand the zone.
Yoshinori Moriyama, a senior agency official in charge of measures concerning nuclear emergencies, told reporters Thursday the agency asked for the freeze so as to avoid a ''hasty decision'' which could have thrown local governments into confusion.
Following the Fukushima nuclear crisis, triggered by the March 11 earthquake and tsunami last year, the commission decided to expand the priority disaster mitigation zone to a radius of 30 km from plants and set the area within a radius of 5 km as subject to immediate evacuation, as initially envisioned by the commission in 2006.