Regulator approves Ikata 3 safety upgrades

Unit 3 of the Ikata nuclear power plant in Japan's Ehime prefecture has moved a step closer to restarting after the country's nuclear regulator approved Shikoku Electric Power Company's 'construction plan' to strengthen the unit.

Unit 3 of the Ikata nuclear power plant in Japan's Ehime prefecture has moved a step closer to restarting after the country's nuclear regulator approved Shikoku Electric Power Company's 'construction plan' to strengthen the unit.

Shikoku's three-unit Ikata plant (Image: NRA)

The utility originally submitted its construction plan for the unit - an 846 MWe pressurized water reactor - to the Nuclear Regulation Authority (NRA) on 30 October 2015. However, the NRA identified a number of revisions required during its review of the application. Shikoku presented the NRA with an amended plan earlier this month taking into account the additional requirements.

Shikoku today announced that the NRA had approved its construction plan for Ikata 3. The plan is the second of three applications required during the restart process.

Under Japan's reactor restart process, plant operators are required to apply to the NRA for: permission to make changes to the reactor installation; approval of its construction plan to strengthen the plant; and, final safety inspections to ensure the unit meets new safety requirements. Operators are required to add certain safety-enhancing equipment within five years of receiving the NRA's approval of a reactor engineering work program.

Shikoku submitted its engineering work program for Ikata 3 - an 846 MWe pressurized water reactor - to the NRA in July 2013. This was approved by the NRA in July last year. That approval - which means the NRA considers the reactor, and the plant as a whole, to be safe for operation - represented by far the major part of the licensing process.

In January, Shikoku applied to the Japanese regulator to construct a back-up emergency response building at Ikata 3 as well as to install additional air-cooled emergency gas turbine generators at the unit.

Now that its construction plan for Ikata 3 has been approved, Shikoku can request the NRA carry out final pre-operational safety inspections of the unit, which should clear the way for it to resume commercial operation.

The unit is expected to become the fifth Japanese reactor to resume operation under new safety standards introduced following the March 2011 accident at the Fukushima Daiichi plant.

Unit 1 of Kyushu Electric Power Company's Sendai plant in Kagoshima prefecture was the first to be restarted last August, followed by Sendai 2 in October. Unit 3 of Kansai Electric Power Company's Takahama nuclear power plant in Fukui prefecture resumed operation on 29 January. Takahama 4 was restarted on 26 February, but has remained offline since 29 February following an automatic shutdown of the reactor due to a "main transformer/generator internal failure". However, an injunction imposed by a district court on 9 March has kept both Takahama 3 and 4 offline.

Researched and written
by World Nuclear News