Japan to tighten nuclear incident reporting rules

Tokyo, Mar 23: Japan plans to require nuclear power plant operators to report all incidents involving the mishandling of nuclear fuel rods, the trade minister said today, after a spate of admissions this month of past unreported incidents at reactors around the country.

Japan's top utility Tokyo Electric Power Co. (TEPCO) and Hokuriku Electric Power Co admitted this month that they had not reported past cases of mishandling fuel rods that led to self-sustaining nuclear fission chain reactions, or ''criticality'' incidents.

''We will revise the nuclear reactor regulation law,'' Trade Minister Akira Amari told reporters today.

He said the government would require reports on all cases of fuel-rod mishandling, even if they do not lead to criticalities.

Amari said the revision would be made ''as soon as possible,'' though he did not elaborate.

The current regulations, which took effect in 2003, require that utilities report such cases only when they lead to criticalities.

''After the revision is made, if nuclear fuel rods show unexpected moves when nuclear reactors are shut and the rods are not controlled (by engineers), all such cases should be reported,'' Amari said.

Utilities are now reporting past incidents at nuclear power plants to the government after the Trade Ministry ordered them in November to go through power plant records and report their findings by the end of March.

Aamari said he might consider further revisions to the rules to broaden the requirements for nuclear power plant operators to report potentially critical incidents.

Hokuriku Electric last week admitted it had covered up data on such an incident in 1999. TEPCO said yesterday there was a criticality incident at one of its plants in 1978 that may have lasted as long as seven and a half hours.

Two other utilities said they had experienced similar incidents in which fuel rods fell down within reactor cores years ago, but they did not report the incidents at the time as they did not lead to nuclear chain reactions.

All the units affected were closed for regular inspections when the incidents occured.

Reuters