Earthquake rattles Japan’s nuclear revival

The 2024 New Year’s Day 7.6 magnitude earthquake on Japan’s west coast with tsunami warning sirens sounding along the Sea of Japan brought back horrific memories of the devastating March 11, 2011 Great East Japan Earthquake and the triple meltdowns at the Fukushima Daiichi nuclear station. However, no radiation increases have been reported following the January 1, 2024 seismic event. Among the nation’s 33 still operable nuclear reactors remaining in Japan of the 54 units at the time of 2011 nuclear catastrophe, 12 have restarted power operations under more stringent post-Fukushima safety standards established by the new Nuclear Regulatory Authority (NRA).  Another five units have now received permission to restart and are undergoing final certification to include local government permission to do so. Another ten reactors are still undergoing inspections for a possible restart. A total of nine reactors have not applied for restart, and 24, including ten of Tokyo Electric Power Company’s reactors in Fukushima Prefecture, are being permanently decommissioned. The restarted plants are: Sendai-1 and -2, Genkai-3 and -4, Ikata-3, Mihama-3, Ohi-3 and -4 and Takahama-1, -2, -3 and -4.

Seven of those operable reactors (Mihama Unit 3, Ohi Units 3 and 4 and Takahama Units 1, 2, 3 and 4,) were at sites impacted by Japan’s first earthquake of 2024.  The death toll is expected to continue to rise past the 73 recovered bodies with those still buried in the rubble. The quake generated a coastal tsunami warning (the maximum recorded at three meters) forcing the evacuation of more than 100,000 Japanese to move to higher ground in the western prefectures that was lifted on Tuesday morning.  Following the initial earthquake, the Japan Meteorological Agency has now detected more than 500 tremors between January 1st through January 3rd and warning to brace for more aftershocks, landslides and new tsunami alerts in the coming days.

There are several electric companies with reactor sites in Japan’s most recently affected earthquake zone.

Tokyo Electric Power Company’s Kashiwazaki-Kariwa station with seven reactor units were unaffected by the quake. The units were not at power because their operating licenses have been on regulatory hold since 2007 and then extended following the destruction of four units and permanent closure of all six of TEPCO’s Fukushima Daiichi reactors in 2011 on Japan’s East Coast.

Kansai Electric Power Company reported Monday there were no problems following the initial quake at its 11 reactors at the Mihama, Ohi and Takahama plant sites. Seven of the units are currently licensed to operate, while the other four reactors are in the process of being decommissioned.

Hokuriku Electric Power Company’s Shika nuclear station Units 1 and 2, the closest reactors to this earthquake’s epicenter, reported that radioactive cooling water sloshed out of a “spent” fuel pool during the quake that was then followed by an interruption of electrical power to the cooling water pumps to the same nuclear waste storage pond (now resumed). The power disruption was caused by transformer failures due to pipe breaks, oil leakage and an explosion as a result of the quake. NHK News Service also reports that the tsunami water level rose to three meters (over six feet) on the Shika reactor site. Both Shika units have been closed awaiting completion and approval of post-Fukushima safety-related seismic and flooding backfit work and approval for restart following the 2011 disaster.  [UPDATED  Jan. 10, 2024] The shaking of the Shika nuclear power station is  reported to have exceeded its earthquake design criteria.

Japan Atomic Power Company is reporting no problems at the Tsuruga nuclear power plant in Fukui Prefecture and its two reactors, one of which is being decommissioned, while the other has been temporarily shut down for routine inspections.

The January 1st earthquake could not have come at a more critical time for Japan which is in the midst of a major reversal of its  national energy policy to phase out reliance on atomic power in the wake of the 2011 nuclear catastrophe. In February, 2023 Prime Minister Fumio Kishida approved a nuclear power revival policy to not only accelerate bringing its regulatory idled atomic plants back on line but to extend the operational lifespan of its reactor fleet beyond 60 years and build new reactors to replace the decommissioned units. However, nuclear power is still controversial among a large and active portion of Japanese civil society and their representational local government remain formidable opponents to the continued and/or  expanded reliance on dirty, dangerous and expensive atomic power.

[Photo: Japan’s Shika nuclear power station, Wikimedia]