Tokyo Electric Power Company Holdings Inc. said Thursday it has submitted a plan to the nuclear regulator to begin loading fuel in a reactor at an idled plant, northwest of Tokyo, next month, as part of moves to potentially restart the facility.

The proposed loading of the No.7 reactor at the Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture from April 15 was submitted to the Nuclear Regulation Authority. TEPCO has yet to restart any of its reactors halted after the Fukushima Daiichi nuclear disaster triggered by the March 2011 earthquake and tsunami.

No timeline for a restart has been decided, TEPCO said. The central government supports the move as resource-poor Japan looks to again have nuclear as a significant contributor to the country's power generation mix, and improve the tight power supply conditions in the eastern region including the heavily-populated Tokyo metropolitan area served by TEPCO.

File photo taken in April 2021, shows the No. 6 (R) and No. 7 reactors at Tokyo Electric Power Company Holdings Inc.'s Kashiwazaki-Kariwa nuclear power plant in Niigata Prefecture. (Kyodo)

The government has been urging Niigata Gov. Hideyo Hanazumi to approve the plant's restart.

But Hanazumi has been calling for extensive discussions on measures to ensure the safety of local residents in the event of a nuclear accident.

The seven-reactor facility in Niigata Prefecture has a maximum output capacity of 8.212 million kilowatts and is one of the world's largest producers of electricity.

After loading the seventh reactor with nuclear fuel, TEPCO hopes to bring it to criticality and ascertain whether any irregularities are present before gradually increasing its output.

The plant's manager Takeyuki Inagaki said at a press conference Thursday that work to bring the reactor to criticality could only begin with local approval.

All 12 reactors at six nuclear facilities approved for restarts in the country's west and southwest received local assent before the loading of nuclear fuel.

Local trust in TEPCO has been damaged by safety flaws identified at the plant that led the NRA to issue an operational ban in force from April 2021 until it was lifted in December following an inspection of strengthened counterterrorism measures at the site.

The powerful Jan. 1 Noto Peninsula earthquake in nearby Ishikawa Prefecture has also heightened local safety concerns over a possible evacuation in the event of a nuclear accident.

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