Ventilation systems not sufficient, says NRA

January 18, 2013

Nuclear watchdog to require filtered ventilation system for boiling-water reactors

http://mainichi.jp/english/english/newsselect/news/20130118p2a00m0na008000c.html

Nuclear reactors of the same type as those at the crippled Fukushima No. 1 nuclear power plant will be required to be equipped with a filtered ventilation system before reactivation, a Nuclear Regulation Authority (NRA) commissioner has told the Mainichi.

In an interview with the Mainichi Shimbun on Jan. 17, NRA Commissioner Toyoshi Fuketa said the NRA will mandate plant operators to equip boiling-water reactors (BWRs) with ventilation systems using filters capable of removing radioactive materials, when the regulatory body starts screenings for plant reactivations under new safety measures sometime after July.

Among the 50 nuclear reactors across Japan, there are 26 BWRs including "upgraded" models. While most of them are equipped with ventilation systems, they do not have filters.

"It can't be said sufficient measures have been taken without them," Fuketa said.

Because it will take several years to install the filtered ventilation systems, reactivation of suspended reactors is likely to be significantly delayed.

Meanwhile, the NRA is poised to set an unspecified grace period for pressurized-water reactors (PWR) -- such as those in operation at the Oi nuclear plant in Fukui Prefecture -- on the grounds that those reactors are housed in larger containers, making it less necessary to equip them with ventilation systems, according to Fuketa.

The NRA is also considering obliging plant operators to set up a "second control room," from which they can remotely control the cooling of reactors.

Fuketa said the NRA is expecting to receive applications for the reactivation of "a few reactors" from power companies in July.

As for the possibility of some reactors being decommissioned after failing to meet the new safety standards, Fuketa said, "We will show no leniency in that respect."

Regarding the extension of the operational period for reactors that have passed their 40-year limit, he said the NRA will not approve their operation if there have been past problems with their performance, including problems stemming from their operators.