2024 Noto Peninsula Earthquake
A series of earthquakes, the biggest of which measured M7.6 on the evening of 1 January 2024, has stricken the Noto Peninsula in Ishikawa Prefecture. Tsunami flooding has also occurred and the damage has been enormous.
Hokuriku Electric Power Co.’s Shika Nuclear Power Station Unit 1 (BWR, 540 MW) and Unit 2 (ABWR, 1358 MW) are located in the town of Shika, Ishikawa Prefecture, but both have been idled since March 2011. Luckily, neither the earthquake nor the tsunami following it resulted in a large accident there, though it has been determined that some of the tremors exceeded, though just slightly, the expectations. The level of the sea in front of the nuclear power plant (NPP) was raised by a maximum of about three meters. As many as of 18 of the plant’s 116 monitoring posts failed to function.
Water from the spent fuel pools spilled over (and overspills also occurred at Kashiwazaki-Kariwa Units 2, 3, 4, 6 and 7), the coolant pumps stopped temporarily, some of the pools’ testing equipment dropped down from the positions where they were installed, and piping in transformers receiving external power was broken at both units 1 and 2, allowing oil to leak out, resulting in a power outage and some equipment becoming inoperable. Some of the leaked oil flowed as far as the sea. At the spent fuel pools, the standby power units kicked in and have been providing cooling since then to the pools. The seawalls tilted, metallic seal covers fell off, and leaks occurred in purified water tanks. In addition, there was great confusion, with wild changes in the information arriving. Complete restoration of external power is expected to take a half year or more.
There had also been plans for an NPP in Suzu City on the Noto Peninsula. Three companies, Kansai Electric Power Co., Chubu Electric Power Co and Hokuriku Electric Power Co, who had been proceeding jointly with construction plans in two locations in the city 20 years before in December 2003, had announced the suspension of those plans. Alas, those plans turned out to be unrealistic. If they’d not been stymied by an opposition movement, though, this huge earthquake might have had its epicenter right underneath them.
Just to look at the state of the roads and at the government’s slow response gives us a renewed sense of the terror of “nuclear earthquake disasters.” If a severe accident had occurred at the NPP and radioactivity was released into the environment, post-earthquake evacuation would have been extremely difficult. Moreover, a radioactive disaster would have prevented aid from reaching the stricken region and recovery from proceeding.
It is being said that the fault which became the epicenter of this earthquake has a length of 150 kilometers, may have been triggered by a yet-to-be-identified faultline, and that several faults may have been moving in synchronicity, so the earthquake and tsunami have yet to be understood in their entirety. Long-term delays in the safety inspections for the Unit 2 reactor, which Hokuriku Electric Power Co. was hoping to restart, have become inevitable. At a press conference on January 10, Chairman Yamanaka Shinsuke of Japan’s Nuclear Regulation Authority (NRA) said that the time it will take to identify the fault that triggered the earthquake “Will be measured in years, and considering that, I think when all is said and done the inspections will take even longer.”
Operational Ban on Kashiwazaki-Kariwa Nuclear Power Plant Lifted
In March 2021, in connection with the violation of nuclear material protection regulations discovered in 2020, the Nuclear Regulation Authority (NRA) issued an order prohibiting the transfer of specified nuclear fuel materials, effectively prohibiting the operation of the Kashiwazaki-Kariwa Nuclear Power Plant (KKNPP). The NRA lifted the order at the 56th meeting of the NRA on 27 December 2023 on the grounds that Tokyo Electric Power Company (TEPCO), the operator of KKNPP, had shown improvements in their systems and would continue to work to improve them in the future. See CNIC’s statement here
Operation Exceeding 40 Years Greenlighted for Sendai NPP
On 1 November 2023, the Nuclear Regulation Authority (NRA) of Japan approved the extended operation of Sendai units 1 and 2 (each BRW, 890 MW), owned by Kyushu Electric Power Co. in Satsuma-Sendai City, Kagoshima Prefecture. The Unit 1 reactor will exceed 40 years in operation in July 2024 and Unit 2, in November 2025. With the NRA’s approval, they are permitted to extend their operating period to 60 years. If the “Minister of Economy and Industry’s approval can be obtained from the standpoint of ensuring a stable energy supply and contributing to GX,” their operation past 60 years is also possible.
Once the appeal for approval of the extension was adopted on December 12 by the Satsuma-Sendai City Assembly and on December 19 by the Kagoshima Prefectural Assembly, approval of the extension was expressed by the mayor of the former on the 12th and the governor of the latter on the 21st.
Japan and Poland Sign Memorandum of Cooperation for R&D on HTGR
The Japan Atomic Energy Agency and National Centre for Nuclear Research (NCBJ) of Poland have arranged for cooperation on the basic design of a high-temperature gas-cooled reactor (HTGR) in Poland. A contract of about 12 billion yen was concluded in February 2023 and a contract of about 380 million yen for cooperation on safety design, the final stage of the basic design, in March. Education Culture, Sports, Science and Technology Minister Moriyama Masahito of Japan and Polish Climate and Environment Minister Anna Moskwa met online on November 16 to sign a memorandum of cooperation to research and develop an HTGR.
Spent Fuel from Fugen to be Shipped to France in FY2027-31
The previous issue of NIT stated: “Plutonium Recovered through Reprocessing of Fugen Fuel to be Transferred to Orano.” Well, it became clear on 22 December 2023 that there will be a third delay in the shipment plans. The Ministry of Education, Culture, Sports, Science and Technology (MEXT) brought this up when explaining the government’s budget for Fukui Prefecture for FY2024, saying that the transfer was to be delayed a further year, commencing in FY2027-2031 rather than the original FY2023-summer of 2026—a four-year delay.
Even so, Hayashi Takahiro, Deputy Director-General of the Minister’s Secretariat at MEXT, who was tasked with this explanation, insisted “This will have no impact on the decommissioning plans overall. There will be no postponement of the completion date of the decommissioning measures,” supposedly in FY2040.
Delay, Defer and Dillydally
At a meeting of NRA’s Tokai Reprocessing Plant Safety Monitoring Team on 20 December 2023, JAEA reported that vitrification of high-level liquid waste at that plant, currently undergoing decommissioning, would be deferred by 10 years to the end of FY2038. This is the fifth time this work has been suspended since 2016, when vitrification processing began as a special measure to reduce risks. During the years since then, the sum total period the glass fusing furnace has been in actual operation amounts to less than one year. The last time it was suspended was in September 2022, and the fusion furnace is currently undergoing renovation. Initially, it was scheduled to be restarted at the end of FY2024, but defective equipment has necessitated additional work, leading to delays that have brought the outlook to FY2026. As of the end of October 2023, there were 378 cubic meters of high-level radioactive waste remaining within the facilities that had resulted from reprocessing work.
Japan Atomic Power Co. (JAPC) notified the NRA on 21 December 2023 of a five-year delay in the decommissioning of its Tokai Power Station (GCR, 166 MW), which was shut down about 26 years ago, and the measures are to be completed in 2035. That is its fourth delay. Meanwhile, Chugoku Electric Power Co. gave notice on 11 December of a change in plans, postponing the completion of decommissioning of its Shimane Unit 1 reactor (BWR, 460 MW), which was shut down about nine years ago, until FY2049, a delay of four years.
Tohoku Electric Power Co. had been planning to restart its Onagawa Unit 2 reactor (BWR, 825 MW) on 2 September 2023, but announced a delay until May of this year. On 10 January 2024 it announced a further delay of several months for safety-related construction, saying it would investigate the matter in detail to clarify the timing.