Fearful of scaring public, existence of document was denied for months
The government buried a worst-case scenario for the Fukushima nuclear crisis that was drafted last March and kept it under wraps until the end of last year, sources in the administration said Saturday.
After the document was shown to a small, select group of senior government officials at the prime minister's office in late March, the administration of then Prime Minister Naoto Kan decided to quietly bury it, the sources said.
"When the document was presented (in March), a discussion ensued about keeping its existence secret," a government source said.
In order to deny its existence, the government treated it as a personal document of Japan Atomic Energy Commission Chairman Shunsuke Kondo, who authored it, until the end of December, the sources said.
It was only then that it was actually recognized as an official government document, they said.
"The content was so shocking that we decided to treat it as if it didn't exist," a senior government official said.
A private-sector panel investigating the disaster at the Fukushima No. 1 nuclear plant intends to examine whether the government tried to manipulate information during its handling of the crisis.
The panel plans to interview Kan and Goshi Hosono, minister in charge of the nuclear crisis and Kan's former adviser, among others.
Kondo drew up the document at Kan's request and is dated March 25, 2011. The document forecast that in a worst-case scenario the plant's crippled reactors would intermittently release massive quantities of radioactive materials for about a year.
The projection was based on a scenario in which a hydrogen explosion would tear through the No. 1 reactor's containment vessel, forcing all workers at the plant to evacuate because of the ensuing lethal radiation levels.
The document said that in such an event, residents within a radius of 170 km of the power station, and possibly even further away, would be forced to evacuate. Those living within a radius of between 170 km and 250 km of the plant, including Tokyo, could chose to evacuate voluntarily. The wrecked power station is about 220 km northeast of the capital.
Kan admitted in September that a worst-case scenario for the disaster had been drawn up. After parts of it were leaked in December, his successor, Prime Minister Yoshihiko Noda, decided to start treating it as a Cabinet Office document.
"Because we were told there would be enough time to evacuate residents (even in a worst-case scenario), we refrained from disclosing the document due to fear it would cause unnecessary anxiety (among the public)," Hosono, the nuclear crisis minister, said at a Jan. 6 news conference.
Ministry not keeping track
The health ministry has not been keeping track of radiation that workers at the Fukushima No. 1 nuclear plant are exposed to while off-site or off duty, ministry officials said Saturday, prompting concerns that current systems to check exposure may be inadequate.
The health ministry also doesn't check radiation doses that workers are exposed to during decontamination efforts around the wrecked No. 1 plant.
The ministry currently only keeps track of radiation exposure for the plant's employees when they are engaged in work around the facility.
January 22, 2012, Japan Times