On December 22, 2025, about 300 protesters rallied outside the prefectural assembly, holding banners that read "No Nukes" and "We oppose the restart of Kashiwazaki-Kariwa." Photo: screenshot from local media UX Niigata News

Despite persistent concerns among local residents, Japan's Niigata Prefecture on Monday approved the restart of the Kashiwazaki-Kariwa nuclear power plant, the world's largest, more than a decade after the Fukushima nuclear disaster, according to Japanese media. The plant in Niigata is operated by Tokyo Electric Power Company (TEPCO), the operator responsible for the nuclear accident at Fukushima Daiichi nuclear power plant in 2011.

According to the Yomiuri Shimbun, the prefectural assembly's consent means that TEPCO will resume nuclear operations for the first time since the March 2011 core meltdowns at the tsunami-stricken Fukushima Daiichi plant.

Prior to the nuclear accident, TEPCO operated six reactors at the Fukushima Daiichi plant, four reactors at the Fukushima Daini plant in Fukushima Prefecture, and seven reactors at the Kashiwazaki-Kariwa plant in Niigata Prefecture. After the accident, all ten reactors at Fukushima were slated for decommissioning. The Kashiwazaki-Kariwa Unit 6 has remained offline since it was shut down for routine inspection in March 2012, Tokyo Shimbun reported. 

TEPCO is expected to restart the Kashiwazaki-Kariwa plant's No. 6 reactor with an output capacity of 1.35 million kilowatts as early as next month, Jiji Press reported.

According to TEPCO, the Kashiwazaki-Kariwa nuclear power station, straddling Kashiwazaki City and Kariwa Village in Niigata Prefecture, covers an area of some 4.2 million m² . The site is made up of seven power generating units with a total output capacity of 8.212 million Kw.

According to the Tokyo Shimbun, during Monday's assembly session, the LDP submitted a supplementary budget proposal from the prefectural government, which included approximately 31 million yen for public relations expenses related to the restart, along with an attached resolution expressing confidence in Governor Hanazumi. The resolution passed with support from a majority of the 53 assembly members, mainly from the Japanese ruling LDP.

The report added that throughout the regular session that began on December 2, opposition parties repeatedly criticized Niigata Governor Hideyo Hanazumi's earlier public statements about "confirming residents' intentions" and "seeking trust," questioning why such confirmation was not conducted through an election and calling it deceptive. 

On Monday, about 300 protesters rallied outside the prefectural assembly, holding banners that read "No Nukes" and "We oppose the restart of Kashiwazaki-Kariwa," local media UX Niigata News reported.

Tokyo Shimbun reported on November 12 that a November survey targeting residents in nine municipalities within a 30-kilometer radius of the plant, in response to the question of whether "conditions for restart are currently in place," 61 percent of respondents answered "do not think so," forming a majority. Approximately 80 percent of respondents emphasized the need for improvements such as evacuation routes and snow removal equipment in case of an accident, highlighting residents' concerns that a restart would be premature, Tokyo Shimbun reported.

Chang Yen-chiang, director of the Yellow Sea and Bohai Sea Research Institute at Dalian Maritime University, told the Global Times on Monday that the foremost concern surrounding the restart of the nuclear power plant in Niigata is safety. 

“Japan is located on a major seismic belt, making future earthquake risks difficult to predict, which raises fundamental concerns about the safety of its nuclear plants,” Chang said.

 The Asahi Shimbun reported that an earthquake of magnitude 7 or higher in the Tokyo area could kill up to 18,000 people and destroy about 400,000 buildings, according to estimates released by a government expert panel on Friday. 

Media also reported on December 10 that Japan issued a megaquake advisory after a magnitude 7.5 earthquake struck off the eastern coast of Aomori, the northernmost prefecture on Japan’s main island of Honshu.

Furthermore, Chang noted TEPCO and Japanese government’s historical lack of information disclosure is particularly worrying.

The expert believes that to address safety concerns, the international community, including IAEA member states, could consider advocating through the IAEA framework to request Japan to disclose the detailed environmental impact assessment reports and related safety improvement plans for the restart of the plant in Niigata, which would enhance transparency and establish more credible international oversight.