The venting was designed to be through an external stack, but in the absence of power much of it apparently backflowed to the service floor at the top of the reactor building, representing a serious failure of this system though another possibility is leakage from the drywell.
The vented steam, noble gases and aerosols were accompanied by hydrogen. At pm on Saturday 12, there was a hydrogen explosion on the service floor of the building above unit 1 reactor containment, blowing off the roof and cladding on the top part of the building, after the hydrogen mixed with air and ignited.
Oxidation of the zirconium cladding at high temperatures in the presence of steam produces hydrogen exothermically, with this exacerbating the fuel decay heat problem.
In unit 1 most of the core — as corium, composed of melted fuel and control rods — was assumed to be in the bottom of the RPV, but later it appeared that it had mostly gone through the bottom of the RPV and eroded about 65 cm into the drywell concrete below which is 2. This reduced the intensity of the heat and enabled the mass to solidify.
In mid-May the unit 1 core would still have been producing 1. In unit 2 , water injection using the steam-driven back-up water injection system failed on Monday 14, and it was about six hours before a fire pump started injecting seawater into the RPV. Before the fire pump could be used RPV pressure had to be relieved via the wetwell, which required power and nitrogen, hence the delay.
Meanwhile the reactor water level dropped rapidly after backup cooling was lost, so that core damage started about 8 pm, and it is now understood that much of the fuel then melted and probably fell into the water at the bottom of the RPV about hours after the scram.
Pressure was vented on Sunday 13 and again on Tuesday 15, and meanwhile the blowout panel near the top of the building was opened to avoid a repetition of the hydrogen explosion at unit 1.
Early on Tuesday 15, the pressure suppression chamber under the actual reactor seemed to rupture, possibly due to a hydrogen explosion there, and the drywell containment pressure inside dropped. However, subsequent inspection of the suppression chamber did not support the rupture interpretation. Later analysis suggested that a leak of the primary containment developed on Tuesday Most of the radioactive releases from the site appeared to come from unit 2. In unit 3 , the main backup water injection system failed at about am on Saturday 12, and early on Sunday 13 water injection using the high pressure system failed also and water levels dropped dramatically.
RPV pressure was reduced by venting steam into the wetwell, allowing injection of seawater using a fire pump from just before noon. Early on Sunday venting the suppression chamber and containment was successfully undertaken.
It is now understood that core damage started about am and much or all of the fuel melted on the morning of Sunday 13 and fell into the bottom of the RPV, with some probably going through the bottom of the reactor pressure vessel and onto the concrete below. Early on Monday 14 PCV venting was repeated, and this evidently backflowed to the service floor of the building, so that at am a very large hydrogen explosion here above unit 3 reactor containment blew off much of the roof and walls and demolished the top part of the building.
This explosion created a lot of debris, and some of that on the ground near unit 3 was very radioactive. In defuelled unit 4 , at about am on Tuesday 15 March, there was an explosion which destroyed the top of the building and damaged unit 3's superstructure further. This was apparently from hydrogen arising in unit 3 and reaching unit 4 by backflow in shared ducts when vented from unit 3. Units Water had been injected into each of the three reactor units more or less continuously, and in the absence of normal heat removal via external heat exchanger this water was boiling off for some months.
In June this was adding to the contaminated water onsite by about m 3 per day. In January 4. There was a peak of radioactive release on Tuesday 15, apparently mostly from unit 2, but the precise source remains uncertain. Due to volatile and easily-airborne fission products being carried with the hydrogen and steam, the venting and hydrogen explosions discharged a lot of radioactive material into the atmosphere, notably iodine and caesium. NISA said in June that it estimated that kg of hydrogen had been produced in each of the units.
Nitrogen was being injected into the PCVs of all three reactors to remove concerns about further hydrogen explosions, and in December this was started also for the pressure vessels. Gas control systems which extract and clean the gas from the PCV to avoid leakage of caesium were commissioned for all three units. RPV pressures ranged from atmospheric to slightly above kPa in January, due to water and nitrogen injection.
However, since they were leaking, the normal definition of 'cold shutdown' did not apply, and Tepco waited to bring radioactive releases under control before declaring 'cold shutdown condition' in mid-December, with NISA's approval.
This, with the prime minister's announcement of it, formally brought to a close the 'accident' phase of events. The AC electricity supply from external source was connected to all units by 22 March. Power was restored to instrumentation in all units except unit 3 by 25 March. However, radiation levels inside the plant were so high that normal access was impossible until June. Results of muon measurements in unit 2 in indicate that most of the fuel debris in unit 2 is in the bottom of the reactor vessel.
Summary : Major fuel melting occurred early on in all three units, though the fuel remained essentially contained except for some volatile fission products vented early on, or released from unit 2 in mid-March, and some soluble ones which were leaking with the water, especially from unit 2, where the containment is evidently breached. Cooling is provided from external sources, using treated recycled water, with a stable heat removal path from the actual reactors to external heat sinks.
Access has been gained to all three reactor buildings, but dose rates remain high inside. Tepco declared 'cold shutdown condition' in mid-December when radioactive releases had reduced to minimal levels. See also background on nuclear reactors at Fukushima Daiichi. Used fuel needs to be cooled and shielded. This is initially by water, in ponds. After about three years underwater, used fuel can be transferred to dry storage, with air ventilation simply by convection.
Used fuel generates heat, so the water in ponds is circulated by electric pumps through external heat exchangers, so that the heat is dumped and a low temperature maintained. There are fuel ponds near the top of all six reactor buildings at the Daiichi plant, adjacent to the top of each reactor so that the fuel can be unloaded underwater when the top is off the reactor pressure vessel and it is flooded.
There is some dry storage onsite to extend the plant's capacity. At the time of the accident, in addition to a large number of used fuel assemblies, unit 4's pond also held a full core load of fuel assemblies while the reactor was undergoing maintenance, these having been removed at the end of November, and were to be replaced in the core.
A separate set of problems arose as the fuel ponds, holding fresh and used fuel in the upper part of the reactor structures, were found to be depleted in water. The primary cause of the low water levels was loss of cooling circulation to external heat exchangers, leading to elevated temperatures and probably boiling, especially in the heavily-loaded unit 4 fuel pond.
Here the fuel would have been uncovered in about 7 days due to water boiling off. However, the fact that unit 4 was unloaded meant that there was a large inventory of water at the top of the structure, and enough of this replenished the fuel pond to prevent the fuel becoming uncovered — the minimum level reached was about 1.
After the hydrogen explosion in unit 4 early on Tuesday 15 March, Tepco was told to implement injection of water to unit 4 pond which had a particularly high heat load 3 MW from used fuel assemblies in it, so it was the main focus of concern. Initially this was attempted with fire pumps but from 22 March a concrete pump with metre boom enabled more precise targeting of water through the damaged walls of the service floors.
There was some use of built-in plumbing for unit 2. Analysis of radionuclides in water from the used fuel ponds suggested that some of the fuel assemblies might have been damaged, but the majority were intact. There was concern about the structural strength of unit 4 building, so support for the pond was reinforced by the end of July. Each has a primary circuit within the reactor and waste treatment buildings and a secondary circuit dumping heat through a small dry cooling tower outside the building.
The next task was to remove the salt from those ponds which had seawater added, to reduce the potential for corrosion. In July two of the fresh fuel assemblies were removed from the unit 4 pool and transferred to the central spent fuel pool for detailed inspection to check damage, particularly corrosion. They were found to have no deformation or corrosion.
Unloading the spent fuel assemblies in pond 4 and transferring them to the central spent fuel pool commenced in mid-November and was completed 13 months later. These comprised spent fuel plus the full fuel load of The next focus of attention was the unit 3 pool.
In the damaged fuel handling equipment and other wreckage was removed from the destroyed upper level of the reactor building. Toshiba built a tonne fuel handling machine for transferring the fuel assemblies into casks and to remove debris in the pool, and a crane for lifting the fuel transfer casks.
Installation of a cover over the fuel handling machine was completed in February Removal and transferral of the fuel to the central spent fuel pool began in mid-April and was completed at the end of February In June , Tepco announced it would transfer some of the fuel assemblies stored in the central spent fuel pool to an onsite temporary dry storage facility to clear sufficient space for the fuel assemblies from unit 3's pool. The dry storage facility has a capacity of at least assemblies in 65 casks — each dry cask holds 50 fuel assemblies.
Summary: The spent fuel storage pools survived the earthquake, tsunami and hydrogen explosions without significant damage to the fuel, significant radiological release, or threat to public safety. The new cooling circuits with external heat exchangers for the four ponds are working well and temperatures are normal.
Analysis of water has confirmed that most fuel rods are intact. See also background on Fukushima Fuel Ponds and Decommissioning section below.
Regarding releases to air and also water leakage from Fukushima Daiichi, the main radionuclide from among the many kinds of fission products in the fuel was volatile iodine, which has a half-life of 8 days.
The other main radionuclide is caesium, which has a year half-life, is easily carried in a plume, and when it lands it may contaminate land for some time. It is a strong gamma-emitter in its decay. Cs is also produced and dispersed; it has a two-year half-life.
Caesium is soluble and can be taken into the body, but does not concentrate in any particular organs, and has a biological half-life of about 70 days. In assessing the significance of atmospheric releases, the Cs figure is multiplied by 40 and added to the I number to give an 'iodine equivalent' figure.
As cooling failed on the first day, evacuations were progressively ordered, due to uncertainty about what was happening inside the reactors and the possible effects. By the evening of Saturday 12 March the evacuation zone had been extended to 20 km from the plant.
See later section on Public health and return of evacuees. A significant problem in tracking radioactive release was that 23 out of the 24 radiation monitoring stations on the plant site were disabled by the tsunami. There is some uncertainty about the amount and exact sources of radioactive releases to air see also background on Radiation Exposure.
Most of the release was by the end of March Tepco sprayed a dust-suppressing polymer resin around the plant to ensure that fallout from mid-March was not mobilized by wind or rain. In addition it removed a lot of rubble with remote control front-end loaders, and this further reduced ambient radiation levels, halving them near unit 1.
In mid-May work started towards constructing a cover over unit 1 to reduce airborne radioactive releases from the site, to keep out the rain, and to enable measurement of radioactive releases within the structure through its ventilation system. The frame was assembled over the reactor, enclosing an area 42 x 47 m, and 54 m high. The sections of the steel frame fitted together remotely without the use of screws and bolts. All the wall panels had a flameproof coating, and the structure had a filtered ventilation system capable of handling 40, cubic metres of air per hour through six lines, including two backup lines.
The cover structure was fitted with internal monitoring cameras, radiation and hydrogen detectors, thermometers and a pipe for water injection. The cover was completed with ventilation systems working by the end of October It was expected to be needed for two years. In May Tepco announced its more permanent replacement, to be built over four years. It started demolishing the cover in and finished in In December it decided to install the replacement cover before removing debris from the top floor of the building.
A crane and other equipment for fuel removal will be installed under the cover, similar to that over unit 4. A cantilevered structure was built over unit 4 from April to July to enable recovery of the contents of the spent fuel pond.
This is a 69 x 31 m cover 53 m high and it was fully equipped by the end of to enable unloading of used fuel from the storage pond into casks, each holding 22 fuel assemblies, and removal of the casks. This operation was accomplished under water, using the new fuel handling machine replacing the one destroyed by the hydrogen explosion so that the used fuel could be transferred to the central storage onsite.
Transfer was completed in December A video of the process is available on Tepco's website. A different design of cover was built over unit 3, and foundation work began in Large rubble removal took place from to , including the damaged fuel handling machine. An arched cover was prefabricated, 57 m long and 19 m wide, and supported by the turbine building on one side and the ground on the other.
A crane removed the fuel assemblies from the pool and some remaining rubble. Spent fuel removal from unit 3 pool began in April and was completed in February Maps from the Ministry of Education, Culture, Sports, Science and Tehcnology MEXT aerial surveys carried out approximately one year apart show the reduction in contamination from late to late Areas with colour changes in showed approximately half the contamination as surveyed in , the difference coming from decay of caesium two-year half-life and natural processes like wind and rain.
Tests on radioactivity in rice have been made and caesium was found in a few of them. Summary : Major releases of radionuclides, including long-lived caesium, occurred to air, mainly in mid-March. The population within a 20km radius had been evacuated three days earlier. Considerable work was done to reduce the amount of radioactive debris onsite and to stabilize dust.
The main source of radioactive releases was the apparent hydrogen explosion in the suppression chamber of unit 2 on 15 March. A cover building for unit 1 reactor was built and the unit is now being dismantled, a more substantial one for unit 4 was built to enable fuel removal during By the end of , Tepco had checked the radiation exposure of 19, people who had worked on the site since 11 March. For many of these both external dose and internal doses measured with whole-body counters were considered.
It reported that workers had received doses over mSv. Of these had received to mSv, twenty-three mSv, three more mSv, and six had received over mSv to mSv apparently due to inhaling iodine fumes early on. There were up to workers onsite each day.
Recovery workers wear personal monitors, with breathing apparatus and protective clothing which protect against alpha and beta radiation.
The level of mSv was the allowable maximum short-term dose for Fukushima Daiichi accident clean-up workers through to December , mSv is the international allowable short-term dose "for emergency workers taking life-saving actions".
No radiation casualties acute radiation syndrome occurred, and few other injuries, though higher than normal doses, were being accumulated by several hundred workers onsite. High radiation levels in the three reactor buildings hindered access there.
Monitoring of seawater, soil and atmosphere is at 25 locations on the plant site, 12 locations on the boundary, and others further afield. Government and IAEA monitoring of air and seawater is ongoing.
Some high but not health-threatening levels of iodine were found in March, but with an eight-day half-life, most I had gone by the end of April A radiation survey map of the site made in March revealed substantial progress: the highest dose rate anywhere on the site was 0. The majority of the power plant area was at less than 0. These reduced levels are reflected in worker doses: during January , the workers at the site received an average of 0. Media reports have referred to 'nuclear gypsies' — casual workers employed by subcontractors on a short-term basis, and allegedly prone to receiving higher and unsupervised radiation doses.
This transient workforce has been part of the nuclear scene for at least four decades, and at Fukushima their doses are very rigorously monitored. If they reach certain levels, e. Tepco figures submitted to the NRA for the period to end January showed workers had received more than mSv six more than two years earlier and had received 50 to mSv. Early in there were about onsite each weekday. Summary : Six workers received radiation doses apparently over the mSv level set by NISA, but at levels below those which would cause radiation sickness.
On 4 April , radiation levels of 0. Monitoring beyond the 20 km evacuation radius to 13 April showed one location — around Iitate — with up to 0. At the end of July the highest level measured within 30km radius was 0. The safety limit set by the central government in mid-April for public recreation areas was 3.
In June , analysis from Japan's Nuclear Regulation Authority NRA showed that the most contaminated areas in the Fukushima evacuation zone had reduced in size by three-quarters over the previous two years. In August The Act on Special Measures Concerning the Handling of Radioactive Pollution was enacted and it took full effect from January as the main legal instrument to deal with all remediation activities in the affected areas, as well as the management of materials removed as a result of those activities.
It specified two categories of land: Special Decontamination Areas consisting of the 'restricted areas' located within a 20 km radius from the Fukushima Daiichi plant, and 'deliberate evacuation areas' where the annual cumulative dose for individuals was anticipated to exceed 20 mSv. The national government promotes decontamination in these areas.
Intensive Contamination Survey Areas including the so-called Decontamination Implementation Areas, where an additional annual cumulative dose between 1 mSv and 20 mSv was estimated for individuals.
Municipalities implement decontamination activities in these areas. The doses to the general public, both those incurred during the first year and estimated for their lifetimes, are generally low or very low. No discernible increased incidence of radiation-related health effects are expected among exposed members of the public or their descendants. However, the report noted: "More than additional workers received effective doses currently estimated to be over mSv, predominantly from external exposures.
Among this group, an increased risk of cancer would be expected in the future. However, any increased incidence of cancer in this group is expected to be indiscernible because of the difficulty of confirming such a small incidence against the normal statistical fluctuations in cancer incidence. These workers are individually monitored annually for potential late radiation-related health effects. By contrast, the public was exposed to times less radiation.
Most Japanese people were exposed to additional radiation amounting to less than the typical natural background level of 2. The Report states: "No adverse health effects among Fukushima residents have been documented that are directly attributable to radiation exposure from the Fukushima Daiichi nuclear plant accident.
People living in Fukushima prefecture are expected to be exposed to around 10 mSv over their entire lifetimes, while for those living further away the dose would be 0. The UNSCEAR conclusion reinforces the findings of several international reports to date, including one from the World Health Organization WHO that considered the health risk to the most exposed people possible: a postulated girl under one year of age living in Iitate or Namie that did not evacuate and continued life as normal for four months after the accident.
Such a child's theoretical risk of developing any cancer would be increased only marginally, according to the WHO's analysis. The man had been diagnosed with lung cancer in February Eleven municipalities in the former restricted zone or planned evacuation area, within 20 km of the plant or where annual cumulative radiation dose is greater than 20 mSv, are designated 'special decontamination areas', where decontamination work is being implemented by the government.
A further municipalities in eight prefectures, where dose rates are equivalent to over 1 mSv per year are classed as 'intensive decontamination survey areas', where decontamination is being implemented by each municipality with funding and technical support from the national government.
Considering deaths from air pollution and accidents, nuclear power is hundreds of times safer than fossil fuels, like coal and oil. Japan is restarting three nuclear reactors that were built in the s and went offline in Energy Information Administration. In an effort to meet its goal of being carbon neutral by , Japan has now given utility company Kansai Electric Power permission to restart three nuclear reactors that were built in the s and were taken offline in If you have a comment about this article or if you have a tip for a future Freethink story, please email us at tips freethink.
It was completed in , and one-third of its length is concrete, two-thirds a soil-cement mix, and has piles reaching bedrock. Japco plans a 1. Kansai submitted the plans to the government as a precondition for restarting its two Ohi reactors in western Japan. Nuclear risk and safety reassessments — 'stress tests' — along the lines of those in Europe were carried out in After some confusion the government decided that these would be in two stages.
In the primary stage, plant operators assessed whether main safety systems could be damaged or disabled by natural disasters beyond the plant design basis. This identified the sheer magnitude of events that could cause damage to nuclear fuel, as well as any weak points in reactor design. The 'tests' started from an extreme plant condition, such as operating at full power while used fuel ponds are full. From there, a range of accident progressions such as earthquakes, tsunamis and loss of off-site power were computer simulated using event trees, addressing the effectiveness of available protective measures as problems developed.
Stage 1 tests had to be approved before reactors are restarted. In the second stage even more severe events were considered, with a focus on identifying 'cliff-edge effects' — points in a potential accident sequence beyond which it would be impossible to avoid a serious accident.
This stage included the effects of simultaneous natural disasters. A particular focus was the fundamental safety systems that were disabled by the tsunami of 11 March, leading to the Fukushima accident: back-up diesel generators and seawater pumps that provide the ultimate heat sink for a power plant. The stage 1 stress test results for individual plants were considered first by NISA and then by the Nuclear Safety Commission before being forwarded to the prime minister's office for final approval.
Local government must then approve restart. Its findings and comments were forwarded to the new Nuclear Regulation Agency NRA , which is now responsible for approving restarts. They restarted in July and ran through to September , when they were shut down for routine maintenance. As of June , just 10 reactors had restarted. This had heavy water moderator and light water cooling in pressure tubes and was designed for both uranium and plutonium fuel, but paticularly to demonstrate the use of plutonium.
The MWe unit, started up in , was the first thermal reactor in the world to use a full mixed-oxide MOX core. It was operated by JNC until finally shut down in March These have modular construction. Approval by Fukui prefecture was given in March It will be the basis for the next generation of Japanese PWRs. It was expected to be completed in February , but Mitsubishi delayed the NRC schedule "for several years.
It has three active and passive redundant safety systems and an additional backup cooling chain, similar to EPR. It has a core-catcher and is available for high-seismic sites.
The first units are likely to be built at Sinop in Turkey, then possibly in Vietnam. Canadian design certification is under way. The government, with companies including Toshiba and Hitachi-GE, was to share the cost of these. Basic designs were to be finished by , with significant deployment internationally by Power reactors are licensed for 40 years and then require approval for licence extension in year increments. Following the Fukushima accident, the government tightened requirements for approving licence extension beyond 40 years, which became the default limit.
Operators can apply for up to year licence extensions from 40 years, allowing possible 60 years as in the USA. However, this was destroyed in the accident. Construction of the two units was due to start later in and commissioning of the first was due in March NISA approved Kansai's long-term maintenance and management plan for the unit and granted a licence extension accordingly in June , which was then agreed by local government. In October Kyushu applied for a ten-year extension for Genkai 1, but in April all five of these were shut down.
Kyushu applied for a licence extension of Sendai 1 in December , and this with its ten-year ageing management plan was approved by the NRA in August It applied for Sendai 2 in November and this was approved 12 months later.
Despite the approval for continued operation of Fukushima Daini 2, Tepco in July decided to decommission all four units at the plant. In January the NRA approved these issues being handled together with engineering work involved with Kansai meeting safety requirements for the restart of the two Takahama units. Kansai applied for a year licence extension of Mihama 3 and if it had not been granted it was to be finally shut down in December In October the NRA approved a major works programme and in November granted the year licence extension, to In June Kansai confirmed its plans for upgrading the reactor by to take it to 60 years.
The required work was completed in September Kansai applied for a ten-year cold shutdown of Takahama 2 to defer any decision on its future beyond its 40th anniversary in , and in April the NRA approved a ten-year licence extension for it. The NRA confirmed that they meet new safety standards, with seismic rating upgraded to Gal, and in June the NRA approved licence extension to 60 years, the first units to achieve this under the revised regulations. In September Kansai announced that upgrade work on Takahama 3 was completed, allowing the unit to operate for an additional 20 years to a total of 60 years.
The extension was granted in November Chugoku's Shimane 3 was to enter commercial operation in December , but this was delayed to March because control rod drives had to be returned to the manufacturer for modification and cleaning. The start-up date was then deferred until evaluation of the Fukushima accident could be undertaken. Chugoku finished building a 15 m high sea wall in January , and then extended this to a total length of 1.
With construction now almost complete, Chugoku in May sought permission from the local government to apply to the NRA for pre-operation safety assessment to enable it to start. Chugoku submitted its application to the NRA in August following local government approval.
Seismic rating of the unit is Gal. Construction of unit 1 was due to start in August for commissioning in , but was delayed by more stringent seismic criteria, then delayed again in , and commenced in September Seismic criterion is now Gal. J-Power in mid affirmed its intention to complete and commission the unit, and announced resumption of work in October. In September the company said that it planned to complete construction by the end of , and have it in commercial operation in It applied to the NRA for a safety review in December , and in aspects of the safety review were being negotiated with the NRA.
In September , J-Power announced that the screening process of post-Fukushima safety standards had taken longer than anticipated. J-Power expects that process to conclude in , delaying operation of the reactor until at least It would be able to consume a quarter of all domestically-produced MOX fuel and hence make a major contribution to Japan's 'pluthermal' policy of recycling plutonium recovered from used fuel.
Tepco struggled for two years with the loss of its Kashiwazaki-Kariwa capacity — nearly half of its nuclear total — following the mid earthquake. While the actual reactors were undamaged, some upgrading to improve earthquake resistance and also major civil engineering works were required before they resumed operation. Tepco undertook seismic upgrades of units 1 and 5, the two oldest, restarting them in In a one-kilometre southern seawall was constructed, but apparently some of this is on sediments and assumed Ss of Gal.
However the southern part of the site, with units , has proposed Ss of Gal. Units are rated Gal since January Work stopped after the Fukushima accident, though JSW started manufacturing major components in after the accident. In it was reported that it could not afford to proceed with Higashidori, and in December Tepco said it was seeking a partner to build and operate the plant.
Tohoku's Higashidori 2 on the adjacent site as Tepco's was scheduled for construction start in , though the company has yet to decide whether to proceed.
The site is in Higashidori-mura, on the Pacific coast, near Mutsu on the eastern side of the Shimokita Peninsula in Aomori prefecture. The company is building a 2km seawall to protect the site.
Modifying the two s units to current seismic standards would cost about double the above amount and be uneconomic. Hamaoka is the company's only nuclear site, though it said that it recognizes that nuclear needs to be a priority for both "stable power supply" and environment. However, the shutdown of units in May by government edict for modification has set back plans.
In December the NRA said that a fault zone directly beneath the existing Tsuruga unit 2 reactor operating since was likely to be seismically active, and in May it endorsed an expert report saying that the reactor poses a risk in the event of a major earthquake. An international review group investigating the faults with a massive excavation concluded in that the faults were not active, but the NRA accepted another report in March saying that there was an active fault, making its restart unlikely.
Kyushu Electric Power Co. The Ministry of Environment told METI that the project was "absolutely essential, not just for ensuring energy security and a stable supply of electricity In METI began the process of designating it a key power source development project.
Kyushu had expected to start construction in March , for commercial operation in December The small island community of Iwaishima a few kilometres away has long opposed the plant. In October Chugoku confirmed its intention to proceed and awaited a safety assessment from the NRA. In August the Yamaguchi prefectural government renewed a licence for Chugoku to reclaim land for the plant.
In June it was reported that Chugoku Electric Power Co had changed the proposed start date of new reactor construction at Kaminoseki from July to January Chugoku has recently completed geological surveys at the site that have determined there has been no recent seismic activity in the area.
Tohoku Electric Power Co planned to build the Namie-Odaka BWR nuclear power plant from at Namie town in Minami Souma city in the Fukushima prefecture on the east coast, but indefinitely deferred this project early in Most of this capacity was to be nuclear. Early in Chubu Electric Co announced that it intended to build a new MWe nuclear plant by , with site and type to be decided. The Joyo experimental fast breeder reactor FBR has been operating successfully since it reached first criticality in , and has accumulated a lot of technical data.
It is MWt, and has been shut down since due to damage to some core components.
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