Temporary Injunction against Resumed Operation of Ikata Unit 3 Reactor
The Hiroshima High Court issued a provisional decision on January 17 forbidding operation of the Unit 3 reactor at Shikoku Electric Power Company’s Ikata Nuclear Power Station. The original suit requesting an injunction against operation of this nuclear power plant (NPP) was still under dispute at the Iwakuni branch of Yamaguchi District Court, so until an initial judgment is rendered there, operation of the reactor is ordered to stop.
On March 15, 2018, this temporary injunction had been rejected by the Iwakuni branch, who deemed the new regulatory standards to be rational and the judgment of Japan’s Nuclear Regulation Authority (NRA) that the reactor conformed to the standards, reasonable. The Hiroshima High Court’s decision cited two points in overturning that. One was that a decision not to take an insufficiently-studied active fault in the immediate proximity of the reactor grounds into consideration had been “a mistake or an omission,” and the other was that assumptions had been made underestimating the effects of volcanic eruptions.
This same high court also handed down a decision to halt operations at Ikata Unit 3 on December 13, 2017, under a different group of judges. That time, the decision was rescinded by yet another group of judges, who accepted Shikoku Electric Power Co.’s objections. There is no way to say if the decision this time will be sustained or not. However, judgments or provisional decisions are being rendered one after another to halt operations, and this in itself shows that awareness of the dangers of nuclear power is deepening among the judiciary as well.
A series of accidents occur at the Ikata NPP
Shikoku Electric Power Co. declared on January 12, 2020 that it had mistakenly withdrawn one of the control rods of the Ikata Unit 3 reactor during a regular inspection. The workers had been preparing to retrieve the spent fuel, so they had just hoisted up the upper reactor core apparatus (an integral structure consisting of the upper reactor core support plate, upper reactor core plate, upper reactor core support column, control rod cluster guide pipe and other elements), when one rod in the control rod cluster (control rods come in sets of 24, so at Ikata Unit 3, there are 48 rods) failed to separate from the fuel assemblies and got pulled up together with them, they said. Since the boron concentration in the primary coolant had been increased for retrieval of the fuel, subcriticality was maintained despite the state of the control rods. The gravimetric sensor, however, failed to respond to the weight added in lifting the control rod, and seven hours elapsed between the control rod being lifted and the work crew confirming that it had been withdrawn.
Later, it was lowered together with the upper reactor core apparatus and restored to its state prior to lifting. After separation of the control rod cluster had been confirmed, the apparatus was once again lifted and work to retrieve the spent fuel got underway. The cause of the mishap is currently under investigation, and the NRA said, at a public meeting, that it would look into it.
On the 20th of the same month, at the spent fuel pool, an alarm went off indicating that something had fallen when a fuel assembly was being loaded into an inspection rack. It was discovered that the assembly had not fallen but had touched the rack frame. Again, only five days later on the 25th, as part of the regular inspection of a protection mechanism for transmission cables in the indoor switching station for Units 1 and 2, which are in the process of being decommissioned, the No. 4 transmission cable suddenly cut off. It is not known why this happened but the cause is being investigated.
This in turn caused a power blackout at Units 1 and 2 as well as Unit 3, which was also using power from the transmission cables. After 2-3 seconds, power transmission at Units 1 and 2 switched automatically to another cable. At Unit 3, an emergency diesel generator kicked in after about 10 seconds, supplying electricity, following which power supply was switched manually to another transmission cable.
At both Units 2 and 3, there are spent fuel pools where it is necessary to cool the spent nuclear fuel stored there. At Unit 3, the temperature of the spent fuel pool was 33.0 degrees Celsius before the power blackout but had risen 1.1 degrees to 34.1 degrees after five hours. The pool temperature at Unit 2 rose by 0.2 degrees. Shikoku Electric Power Company stated that this is ‘not a significant change.’ The power blackout did not affect the instruments in the central control room. Shikoku Electric announced on the same day that the regular inspection of Unit 3 would be suspended.
Japan’s First Retrieval of Spent MOX Fuel Conducted at Ikata Unit 3,
The Ikata Unit 3 reactor has adopted pluthermal power generation using MOX fuel (a fuel containing plutonium). During the regular inspection this time, spent MOX fuel was retrieved at a commercial facility for the first time in Japan. Sixteen assemblies were retrieved and five new ones are scheduled to be loaded.
The spent MOX fuel cannot be reprocessed at the Rokkasho reprocessing plant, which is under construction, so a new reprocessing plant is needed. Plans for one, however, have been abandoned entirely, so there is nowhere for the spent MOX fuel to go except to storage at the NPP site. Spent MOX fuel produces a higher level of heat than regular spent nuclear fuel and involves risks, so NRA Chairman Toyoshi Fuketa says that after cooling in the pool for a certain time, it should be transferred to dry cask storage. Concerns have been reported, however, such as accumulation of helium gas during long-term storage of spent MOX fuel, so careful evaluation is needed.
Shirahama Town Assembly Establishes Regulation Refusing Importation of Nuclear Waste
The town assembly of Shirahama, Wakayama Prefecture voted unanimously on December 18, 2019 to adopt a bill refusing to allow “nuclear garbage” to be brought into the town. The regulation is titled “Law Promoting the Creation of a Safe and Secure Town,” and it prohibits “the bringing into the town of radioactive substances (meaning nuclear fuel from NPPs and other nuclear power-related facilities or spent nuclear fuel or radioactive wastes) or the construction of facilities to store or dispose of them within the town” that would cause concerns about impacts on the town’s development.
Previously Shirahama was split for a period of 16 years over the issue of attracting nuclear power development in the vicinity of the Hiki River. During that time, it is said that even families and siblings were divided against each other. Since 1998, though, when a mayor who opposed nuclear power was elected, things have calmed down regarding the nuclear issue. Kansai Electric Power Co. (Kanden), however, started hunting around in search of candidate sites for interim storage facilities for spent nuclear fuel, and concerned that Shirahama might become a candidate site, the townspeople formed an opposition movement in December 2017 that has been seeking to have a law enacted rejecting the importation of radioactive substances.
Kansai Electric Power Co. (Kanden) officials accused of misappropriating nuclear funds
Regarding the problem of Kansai Electric Power Co. (Kanden) officials receiving massive amounts of money and gifts (see NIT No. 193), a citizens’ group “Association to Prosecute KEPCO’s Misappropriation of Nuclear Funds” submitted a complaint to the Osaka District Public Prosecutors Office on December 13, 2019, accusing 12 KEPCO officials of aggravated breach of trust and other crimes under Japan’s Companies Act. There are 3,272 complainants, far surpassing the goal of 1,000 at the time the solicitation was issued on October 24.
On November 27, prior to submitting the complaint, Kanden’s shareholders delivered a request to the company’s auditors asking that a suit be filed for damages of about 5.4 billion yen against officials who had damaged the company’s reputation, resulting in decreased share prices. If the company itself does not file the suit within 60 days of that date, the shareholders’ representatives will file it.
Fukushima Daiichi NPP Decommissioning Progress Schedule Revised
The Inter-Ministerial Council for Contaminated Water and Decommissioning Issues adopted a fifth revision of the Mid- and Long-Term Roadmap (progress schedule) on December 27, 2019 regarding measures to decommission the Fukushima Daiichi NPP. The original progress schedule adopted in 2011 called for beginning the extraction of fuel rods from the spent fuel pools within two years, and commencing debris removal within 10 years, completing the decommissioning in 30 to 40 years. The second revision, issued in June 2013, was more specific. Extraction of fuel from the pools of Units 1 and 2 would begin in fiscal 2017, that of Unit 3 in June 2015 and that of Unit 4 in November 2013. Operations to clear debris would begin at Units 1 and 2 in fiscal 2020 and at Unit 3 in fiscal 2021 (fastest case scenario).
Removal of fuel rods from the Unit 4 pool began according to schedule, and that at Unit 3 began in April 2019, four years behind schedule. Operations have continually been plagued with troubles. Regarding Units 1 and 2, in the fifth revision, commencement of operations at Unit 1 has been delayed by 10-11 years until fiscal 2027-28, and operations at Unit 2 are to start in fiscal 2024-25, a delay of seven or eight years. Operations to extract all of the fuel rods are to be completed at all units by the end of 2031. The reason for the delays is that as investigative work has progressed, issues have become apparent where operations are to take place, with large pieces of equipment, such as cranes, being in states of collapse.
Meanwhile, the schedule for removal of debris from Unit 2 has been clarified, with work set to start in 2021, suggesting no delay. Nevertheless, one wonders if that really is the case, given that they say, “The R&D of items necessary for extracting debris and assessing the state inside the reactor containment vessel has been limited, so there are still large uncertainties at this time regarding what methods will be used to remove the debris.” Nothing is said about Units 1 and 3. Prospects for completing the removal of debris from all units by the original target of 2031-36 are rapidly fading.
If ensuring safety is the highest priority, the delays and continued troubles are not bad in themselves. We also appreciate that they say liquid wastes “will not be simply discharged into the ocean.” In the case of debris classified as “possibly posing increased risks if disposed of hastily,” they really ought to avoid haste.
The extracted debris will be stored on site, but nothing has been decided yet regarding treatment and disposal methods, which will be “determined in the third term.” The “third term” starts from December 2021 and lasts until decommissioning is completed. The final destination of the fuel rods extracted from the pools and what varieties of radioactive waste there will be are unknown. There is also disagreement over whether the debris should be removed at all. While giving top priority to ensuring safety, serious consideration needs to be given to an outlook for the overall picture of the final state of the decommissioned reactors.
More Than 13 Trillion Yen for NPP Restarts and Maintenance
In a January 15 dispatch, Kyodo News tabulated the costs of restarting and maintaining NPPs of the electric power companies aiming to restart reactors as of January 2020 and found it had exceeded 13 trillion yen.
Expenses for safety measures necessary for restarting came to a total of 5.4 trillion yen for 15 NPPs. In the case of six of those, maintenance costs of facilities for responding to specific serious accidents, also known as “terrorism countermeasures” were not included, so the actual figure is certain to be higher.
Maintenance costs are incurred regardless of whether reactors are idled or operating, so in the six years from fiscal 2013, when the new regulatory standards were introduced, until fiscal 2018, a total of about 7.2 trillion yen was spent on maintenance at 17 NPPs.
The time periods of safety measure expenses and maintenance expenses also differ, but a simple sum of these comes to about 12.6 trillion yen.