Kansai Electric Power Co. and Japan Atomic Power Co. (JAPC) are decommissioning three nuclear power plants that were shut down after the Fukushima Daiichi nuclear disaster in March 2011 rather than applying to meet requirements introduced in 2013 by the Japanese Nuclear Regulation Authority (NRA), reported World Nuclear News.

Units 1 and 2 at its Mihama plant will be retired by Kansai Electric, while JAPC will decommission Tsuruga Unit 1. Mihama 1 and 2 are both pressurized water reactors (PWRs) and have been in operation since the early 1970s; Unit 1 since 1970 and Unit 2 since 1972.

Tsuruga 1, a 341 megawatt electrical (MWe) boiling water reactor, started up in 1970. Independent studies completed in 2014 confirmed that geologic faults running under the site are inactive. JAPC was quoted as saying that while it would have been technically feasible to bring Tsuruga 1 up to the standards required, the project would be too costly.

Japan's fleet of 48 operable nuclear reactors has been taken out of service since the Fukushima accident. To date, the NRA has received restart applications for 19 units under the revised regulatory regime.

So far, four reactors—Kansai's Takahama 3 and 4 and Kyushu's Sendai 1 and 2—have restart approval from the NRA, with preliminary permission to make design changes to meet new regulatory requirements. Local government approval is also required before they can restart.

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