Jul 31, 2025
The regulator has determined that Tomari 3 complies with safety standards.
Unit 3 of Hokkaido Electric Power Company's Tomari nuclear power plant, Japan's newest reactor, is closer to restarting after the Nuclear Regulation Authority (NRA) deemed it compliant with updated safety standards.
As part of Japan's reactor restart procedure, operators must apply to the NRA for permission to modify the reactor’s installation, approve a construction plan to enhance the plant, and undergo final safety inspections to verify compliance with new safety requirements. Operators must also install specific safety equipment within five years of receiving NRA approval for the engineering work program.
The Tomari facility consists of two 550 MWe pressurized water reactors (units 1 and 2) and a 912 MWe PWR (unit 3), all of which have been offline since unit 3 was shut down in 2012 for routine inspections. Hokkaido EPC aims to restart all three reactors.
The utility requested a review in July 2013 to determine if its upgrade plan for Tomari 3, which began operations in 2009, meets the revised safety standards established after the March 2011 Fukushima Daiichi incident.
Following the approval of a draft report in April, and after a public comment period, the NRA has officially confirmed that unit 3 satisfies the new safety standards, granting Hokkaido EPC a permit to modify the reactor installation. This marks the 18th Japanese reactor to pass the NRA’s safety assessments.
Hokkaido EPC President and CEO Susumu Saito expressed gratitude to the NRA and all involved in the lengthy review process. He stated that the permit acknowledges that safety measures for Tomari Unit 3 align with new standards, viewing it as a significant step toward restarting operations.
The company constructed a new 16.5-meter-high seawall for tsunami protection but subsequently agreed to raise it to 19 meters following NRA recommendations. The seawall's construction is ongoing, with completion expected by early 2027. Hokkaido EPC has also enhanced its earthquake-resistant design to withstand stronger seismic waves, increasing the threshold from 550 gals to 693 gals.
The utility must still secure approval from local governments before restarting Tomari 3.
In May 2022, the Sapporo District Court ruled in favor of an injunction against operations at the three-unit Tomari plant. This followed a lawsuit by around 1,200 local residents filed in November 2011, which claimed the plant lacked adequate earthquake and tsunami defenses and called for decommissioning. Hokkaido EPC is currently appealing this decision at the Sapporo High Court.
Saito emphasized the importance of gaining the local community's understanding for the restart and committed to providing thorough explanations to help foster this understanding.
He also stated that the commitment to enhancing safety at Tomari Nuclear Power Plant is ongoing, with efforts aimed at achieving the highest global safety standards through further improvements and expanded training programs.
The NRA is still evaluating the safety of Tomari units 1 and 2.
As part of Japan's reactor restart procedure, operators must apply to the NRA for permission to modify the reactor’s installation, approve a construction plan to enhance the plant, and undergo final safety inspections to verify compliance with new safety requirements. Operators must also install specific safety equipment within five years of receiving NRA approval for the engineering work program.
The Tomari facility consists of two 550 MWe pressurized water reactors (units 1 and 2) and a 912 MWe PWR (unit 3), all of which have been offline since unit 3 was shut down in 2012 for routine inspections. Hokkaido EPC aims to restart all three reactors.
The utility requested a review in July 2013 to determine if its upgrade plan for Tomari 3, which began operations in 2009, meets the revised safety standards established after the March 2011 Fukushima Daiichi incident.
Following the approval of a draft report in April, and after a public comment period, the NRA has officially confirmed that unit 3 satisfies the new safety standards, granting Hokkaido EPC a permit to modify the reactor installation. This marks the 18th Japanese reactor to pass the NRA’s safety assessments.
Hokkaido EPC President and CEO Susumu Saito expressed gratitude to the NRA and all involved in the lengthy review process. He stated that the permit acknowledges that safety measures for Tomari Unit 3 align with new standards, viewing it as a significant step toward restarting operations.
The company constructed a new 16.5-meter-high seawall for tsunami protection but subsequently agreed to raise it to 19 meters following NRA recommendations. The seawall's construction is ongoing, with completion expected by early 2027. Hokkaido EPC has also enhanced its earthquake-resistant design to withstand stronger seismic waves, increasing the threshold from 550 gals to 693 gals.
The utility must still secure approval from local governments before restarting Tomari 3.
In May 2022, the Sapporo District Court ruled in favor of an injunction against operations at the three-unit Tomari plant. This followed a lawsuit by around 1,200 local residents filed in November 2011, which claimed the plant lacked adequate earthquake and tsunami defenses and called for decommissioning. Hokkaido EPC is currently appealing this decision at the Sapporo High Court.
Saito emphasized the importance of gaining the local community's understanding for the restart and committed to providing thorough explanations to help foster this understanding.
He also stated that the commitment to enhancing safety at Tomari Nuclear Power Plant is ongoing, with efforts aimed at achieving the highest global safety standards through further improvements and expanded training programs.
The NRA is still evaluating the safety of Tomari units 1 and 2.