MARCH
2017
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SimplyInfo.Org Fukushima Daiichi 6th Anniversary Report
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Introduction This report compiles our work for the last year and data from multiple sources including the NDF, TEPCO, IRID and others. While minimal information is circulated in the press, significant work to investigate and deal with the disaster have been ongoing. The highest current priority is the location of the melted fuel and the development of solid plans for the fuel’s removal. The largest technological challenge remains the development of equipment capable of operating in the astronomically high radiation fields inside containment. The decommissioning concepts for Fukushima Daiichi have evolved over time and as more information has been collected. Preliminary plans are in place, many times with alternate plans where information is still lacking. Some have taken issue with describing the response at the disaster site as “decommissioning” as that terminology usually applies to a functional facility being retired and taken down. This is the nomenclature the government and TEPCO have opted to use. We use it here for the sake of clarity rather than agreement that this is a mere decommissioning. It is a far more monumental task. Also included is coverage of the environmental, health and social impacts of the disaster in addition to the technical issues over the last year. A bibliography is provided at the end of this report.
The Sarcophagus Question This was the sole piece of news out of the Nuclear Damage Compensation and Decommissioning Corporation report (NDF report) that the news media focused on. The initial Japanese report included this section. Once this information was made more public by the media, NDF abruptly issued a revised report that did not include this section and insisted that they really were not working on a plan to build a sarcophagus at Fukushima Daiichi. The initial report clearly shows they were establishing this as a fall back plan. The long term instability of the reactor buildings was cited as a concern related to considering a sarcophagus. The original report also admits long term problems related to maintenance and containing contamination in such a structure. They did insist that fuel debris should be removed first in any case and that this is very much a plan b in their eyes. If they were to consider a sarcophagus solution at some later point in decommissioning it would leave an existing contamination problem due to heavily contaminated soil, groundwater and in the remaining structures. There is some speculation that the frozen wall could be used as preparation for a sarcophagus type isolation system. Early disaster response concepts considered installation of an underground concrete wall. This was eventually scrapped due to cost and complexity. Either concept could conceivably be employed as part of a sarcophagus plan. To date NDF and other parties have not admitted that the frozen wall could serve such a purpose. This would still have the potential to leach or leak into the sea. No specific concept or design was mentioned for this plan. The later hastily revised version of the NDF report attempts to walk back the sarcophagus plan.
The Meltdown Manual The existence of a TEPCO meltdown manual emerged in 2016. Five TEPCO employees admitted they knew of the manual as they were tasked with maintaining it. This set of admissions ran in direct conflict with earlier statements from TEPCO that there was no such emergency manual and that there was no official measure of when a meltdown should be declared. TEPCO briefly tried to blame the entire scandal on the sitting national government at the time of the disaster, claiming they compelled TEPCO to hide the meltdowns. By June of 2016 the current president of TEPCO, Naomi Hirose admitted there was a purposeful cover up by the company back in 2011. TEPCO denied the existence of meltdowns in the reactors until May of 2011. It has taken until recent years for the true scope of the meltdowns to be slowly admitted to the public. The 2016 admission of the existence of the manuals in the home office and the threat of a lawsuit by the DPJ (Democratic Party of Japan) who was the political party in charge in 2011 made the continued denials of the 2011 cover up impossible to continue.
Spent Fuel Removal Spent fuel in the unit 4 spent fuel pool was completely removed as of 2014. Fuel in the pools of units 1, 2 and 3 are prioritized due to building damage. This fuel removal is also a prerequisite to conducting building demolition and modification needed to begin the larger task of removing fuel debris from the reactors. The spent fuel in units 1-3 poses one of the most significant on site risks. Successful removal of that fuel to the common pool or storage casks would drastically reduce the overall risks from the facility. Unit 1 spent fuel removal Spent fuel removal at unit 1 is scheduled for FY2020. Efforts to remove damaged building debris and rubble is underway. The collapsed roof and debris will need to be completely removed before they can conduct a detailed analysis of the conditions within the spent fuel pool.
Unit 2 spent fuel removal The current plan for unit 2 is to completely remove the top level of the building above the refueling floor. A defueling building would then be installed over the top to conduct the fuel removal. This work would include removing the roof, upper walls, and the overhead crane. Research on how to conduct this task is currently underway. High radiation levels around the reactor well have continued to complicate the needed inspection work and data collection. Robots have been used to gather some initial data on the refueling floor. A series of periscope cameras were also inserted through the roof to gather more visual evidence. The actual fuel removal commencement does not have a solid date scheduled. Currently, a platform has been erected on the land side of unit 2 to be used towards this effort to remove the top floor of the building. This platform will be used for heavy equipment that would do some of the wall and roof removal. A defueling building would then be installed in place of the top floor walls and roof. What has not been clearly explained is how they would prevent ongoing leaks of radiation to the environment during this work. Unit 2 had been the largest source of radioactive contamination to the air until a filtration system was put in place back in 2014 that included a HEPA filter system.
Unit 3 spent fuel removal Spent fuel removal for unit 3 is scheduled to begin in FY2018 after repeated delays. Damaged building debris and both cranes were removed from the refueling floor. The work to remove smaller debris and install layers of radioactive shielding has been underway since 2015. Radiation levels have been decreased but still pose a risk to workers spending time on the refueling floor. TEPCO has purchased a modular defueling building currently housed at the training facility at Onahama Port in Iwaki. Workers there are practicing the steps needed to install this building on top of unit 3. The defueling building installation was intended to be done mostly using remote equipment. The current process will require workers to enter the refueling floor and manually bolt the structure to the existing base. Additional shielding has been added to the design in an attempt to reduce the amount of exposure these workers will receive. The preparation work for the defueling building is nearly complete. Portions that connect to the building are undergoing installation. A date for placement of the remaining defueling building sections has not been given but it is likely to take place in early 2017. The actual work to remove fuel from unit 3’s spent fuel pool will be done completely with robotic equipment to limit worker exposures.
Unit 5 spent fuel removal Spent fuel removal at unit 5 has not been recently addressed. This unit had very minimal damage and did not suffer a meltdown. Work to remove fuel in this unit will likely be conducted through normal means. Due to the need to prioritize work at units 1, 2 and 3, this may be delayed for years.
Unit 6 spent fuel removal Unit 6 did not suffer a meltdown or significant damage. Excess spent fuel from unit 4 was moved to unit 6 after the common pool became crowded. Removal of spent fuel from unit 6 has had a low priority.
Reactor Inspections Work has been underway since 2011 to inspect and collect data within the reactor buildings and reactor containment structures. What data has been collected to date is compiled to help guide decommissioning activities.
Unit 1 This unit has had more inspections than the other two units that suffered meltdowns. This work includes scope inspections of containment, the torus room, a muon scan of the reactor vessel and a pair of robot inspections in containment. Multiple robot inspections of the torus room and 3D spatial data collection of accessible building areas has also taken place. Gamma camera visualizations of accessible areas of the reactor building and torus room were completed, some in conjunction with the 3D data collection. IRID unveiled the newest robot for unit 1 in early 2017. This improved version of the shape changing robot by Hitachi that inspected unit 1’s containment is dubbed Pmorph. Pmorph includes an on board camera and radiation detector that can be lowered down through the metal floor grating inside containment. This will be used to take readings and a closer look at a series of locations along the containment concrete floor. Inspection of the lower pedestal doorway will also be conducted. The area is suspected of being where molten fuel flowed out of the pedestal and across the containment floor.
Unit 2 Unit 2 has had multiple scope inspections inside containment. The torus room has been inspected in detail using multiple robots. Two muon scans have been completed. A series of containment inspections took place in early 2017. Using a robotic cutting rig attached to the CRD hatch in early January of 2017, a hole was successfully cut in the hatch door. Work outside of containment had to be done with robotic equipment and heavy shielding due to a 9 Sievert/hour radiation reading found around the CRD hatch. After reworking the original plan, the cutting work took place, with some having to be done manually by workers. The ability to cut sealable passage into the containment structure is a technology that will be reused in future work.
The group of containment inspections included use of a scope with a camera capable of tilting various directions. The findings of this initial work showed how challenging the conditions inside containment truly were. A high radiation area inside containment but outside of the reactor pedestal was estimated at over 500 Sieverts/hour, it was later downgraded to 210 Sieverts/hour using a more accurate sensor on the Scorpion robot. Views inside the pedestal found melted fuel, reactor debris and a 1 meter hole melted in the metal floor grate.
After the scope inspections TEPCO opted to send in a cleaning robot. Knowing the high radiation field further down the CRD rail could disable the robot, they decided to take the chance of losing the robot inside containment. This robot managed to remove a small section of debris that appeared to be both porous and easily broken apart. The debris may be from melted reactor materials. After operating successfully, the camera on the front of the robot began to fail due to the high radiation levels. The robot was abruptly removed from containment before it could completely fail. This left the CRD rail partially covered in debris.
The decision was later made to send in the Scorpion robot even though it would not be capable of traversing the floor grate in the pedestal due to the extensive damage that was recently discovered. They knew Scorpion could die due to the high radiation levels. The robot did manage to collect data and further view inside the pedestal to collect more new imagery. As Scorpion traveled back up the CRD rail the remaining debris rendered one of the tracks on the robot inoperable. The tether cable was severed and Scorpion was abandoned inside containment.
Additional images gathered by Scorpion helped confirm the extent of the damage. The melt hole can be seen in the image below. Other deformity due to heat and melted fuel can be seen on the additional image of the grate.
This work has confirmed that the fuel did melt through the bottom of the reactor vessel. Based on the visual evidence gathered, unit 2 may have had a slow melt and release of the molten fuel into the containment vessel. More data collection is needed to further confirm this and better understand the consequences of unit 2’s meltdown. We compiled this visual estimate of where the known melt-hole resides in context with the reactor and other structures inside containment. This may indicate a fuel melt out path but may not be the only one, just the only one found so far.
The radiation levels found inside unit 2 surprised TEPCO and the investigation team doing the work. The later confirmed 210 Sievert/hour reading is lower than the initial estimates but this level is still extremely deadly to humans and electronic equipment. Current information shows the high radiation level appears to be very isolated to one area. Why it is not causing high radiation levels further from this area is not yet understood. In the diagram below the radiation levels are matched to a number on the diagram. Levels inside the pedestal were actually lower than the high radiation area. This was unexpected as the existing information has all assumed the melted fuel is likely to be somewhere in the pedestal area. Higher radiation levels were expected inside the pedestal rather than out.
What is not known is the exact location of the bulk of unit 2’s fuel. Muon scans completed in 2016 confirmed the fuel is not in the reactor vessel in any significant amount. The fuel may have collected on the concrete floor of the pedestal then proceeded to burn down into the thick concrete basemat of the reactor building. How far it may have burned down and if it burned down far enough to escape the building is not known. Our unit 2 extended report published in 2015 elaborates further on theories of unit 2’s failure and potential melt through the basemat concrete.
The above graphic is fast Fourier transform adjusted to remove excess noise on the original image. This showed that no fuel likely remains in the reactor vessel, similar to what the first muon scan of unit 2 found. Further inspection work has not been announced for unit 2. TEPCO and the affiliated organizations are currently reviewing the results of the recent containment inspection to determine what the most useful next steps would be. A phenomenon we noticed back in 2012 appears to be continuing. Unit 2 appears to have a sort of micro-climate inside containment. Earlier inspections showed considerable amounts of condensation raining down inside containment. Inspections in 2017 showed lesser amounts of this behavior. Water seen raining down inside the pedestal is more likely to be from the water injection process. The larger process of condensation appears to be independent of that effort. Ambient temperatures found in containment in 2017 were roughly 18 Celsius (65 Fahrenheit).
Unit 3 No investigation work has taken place in 2016. Most of the ongoing effort at unit 3 has been related to preparation and installation of the defueling building to remove the spent fuel. One scope inspection has been conducted into unit 3’s containment, this took place in 2015. Deep standing water was found and a radiation level of about 1 Sievert/hour was recorded above the water. Unusual light colored thick blobs were deposited on most of the structures inside containment.
A single robot inspection of unit 3’s torus room was conducted in previous years. The robot failed part way through the work. Some gamma camera inspection have been done inside unit 3’s reactor building. This work was done in previous years.
Fuel Debris Estimation & Location Risks related to the fuel debris and future removal process include high radiation levels, the ability to produce hydrogen, potential for criticality and damage to the support structures inside containment. The radiation levels in the areas of suspected fuel debris are expected to have reduced considerably but these levels still remain lethal to humans and equipment. TEPCO considers the fuel debris to be in a “stable state� but lacks the data accuracy to confirm this conclusively. Unstable fuel debris that has the ability to relocate is considered the largest risk. This unstable fuel poses more risk for leaking to the outer environment or gathering in a configuration that could cause a criticality. Unstable fuel debris would be any materials containing reactor fuel that is easily broken into small pieces or has already fragmented. Removing this type of fuel debris is prioritized due to the risk level. The long term instability of the damaged reactor buildings is also a serious concern. The buildings will need to withstand further earthquakes, natural erosion and other factors that could cause the already damaged buildings to further decay. Piping systems are at risk of corrosion due to age, use of salt water during the initial disaster and standing water. Certain pipe systems are critical to the ability to seal then flood containment vessels and otherwise keep the containment systems sealed. The exact location of the fuel debris remains a challenge. Various methods have been used including computer modeling, detection of heat by temperature readings, muon scans and other methods. We have included in our analysis of the issue, the location of high radiation readings. This is something TEPCO and NDF have not formally added to the process though these readings create obvious hints to the location of fuel debris. The results for all three reactors at this point conclude that most or all of the fuel is not in the RPV (reactor vessel) and likely resides somewhere in the PCV (containment vessel). Beyond these assumptions they provide little detail at this point. There is also not enough clarity to promise that the fuel actually does reside in the PCV rather than having found partial pathways out of containment in some cases. Future work to try to physically investigate areas of containment and other deep areas of the reactor buildings will be key to determining with more clarity, where the fuel is.
Fuel debris retrieval policies for each unit have a deadline of FY2017. A retrieval method for the first unit to be addressed is due by FY2018 and work commencement by December of 2021.
Fuel debris compositions estimates An important distinction was made in the NDF report. They would only consider melted materials that contained an amount of melted fuel pellets within them as fuel debris. This also does not consider the small fuel particles to be fuel debris. Yet both of these are a danger to the environment and would be a contributing source of radiation. At this point the various involved parties have not speculated on the exact composition of fuel debris materials expected at Fukushima Daiichi. No public admission has been made that they have retrieved fuel debris samples. Expected types based on our research into the fuel debris found at Three Mile Island and Chernobyl could include these types.
Black corium, a melted substance that has high amounts of metal along with uranium from the fuel. The high amounts of iron come from the steel components that melt along with the fuel. This is usually found close to the reactor. Brown corium, a melted substance that has higher amounts of uranium and can include concrete components. Pumice type corium, this is brown corium that has been rapidly cooled by a large amount of water. This type can break into small pieces and is highly mobile due to this. Corium viewed on the most recent containment inspection of unit 2 included some unexpected materials. Located on the CRD rail, this material was black, porous and broke apart quite easily. There was a significant amount of this material deposited on the rail. The rail itself is bare steel so these materials were not burned paint from the rail. The actual composition is currently a mystery. Sampling of this material seems a relatively easy and prudent step. Such work has not yet been announced. Japan Atomic Energy Agency (JAEA) has been conducting a series of research experiments as part of the Collaborative Laboratories for Advanced Decommissioning Science (CLADS) decommissioning project. These seek to estimate what the makeup of the corium inside the reactors at Fukushima Daiichi could be. One technology in the research phase would use fiber optics and lasers to reach near the corium and create estimates of the composition of that material. If this reaches implementation it would be a massive leap forward in technical capability. JAEA has created sample corium examples in the laboratory. These are produced using various ratios of steel, uranium fuel and other materials. These known samples will be used as references as they encounter actual corium samples in the reactor buildings. A number of additional factors may influence the composition of the corium. Concrete is likely to be mixed with the larger masses of fuel. As the fuel burned into the concrete, the materials from the concrete mixed into the corium, changing the composition. Salt water injected into the reactors early in the disaster may have also changed the composition of the corium. Other substances such as boron and hydrazine may have also modified the composition. This will require sampling of the corium in order to fully understand the real world conditions found inside the reactors.
Decay Heat, Air and Water Cooling JAEA provided this pair of 50 year graphs for radiation levels and decay heat within the melted fuels. They did not mention why unit 2 was not included in the graph.
We covered the known factors about decay heat in our recent report, Fukushima Daiichi Decay Heat & Corium Status Report. Currently, estimating more exact decay heat calculations is a challenge due to the limited understanding of the corium location, composition and volume. TEPCO has attempted to reduce the water injected into the reactors that has been ongoing since 2011. Unit 1 has achieved the most significant water reduction to date. This process involved slightly reducing the water injection rate, then monitoring all data related to the reactor to look for changes. Hydrogen production, xenon gases, temperature and radiation levels are tracked before the next reduction is approved. There is no purposeful air cooling of the corium or reactor containments. There is an established trend of seeing cooler temperatures inside containment and in the spent fuel pools over the winter vs. the summer. The outside environment has at least a noticeable impact.
Turning Reactors In To Hot Cells This concept has taken on multiple applications. A hot cell is a radioactive containment that allows workers to manipulate materials and equipment from outside the cell to protect themselves from radiation and also to prevent the escape of radioactive materials. Work to insert robots into unit 1 and 2 containment operated on the hot cell concept. A sealed hot cell type chamber housed the robot. This was then attached to a sealed opening in containment that included a door that could be opened once the hot cell was attached. This helps protect the workers, prevents the escape of radioactive contamination and allows the opening to be closed when the robot chamber is not attached. The chamber that houses the robot then safely holds the contaminated robot if they can retrieve it from containment. This can eventually be disposed of as high level radioactive waste.
A larger concept of the hot cell is the eventual plan to send robotic heavy equipment into containment to remove fuel debris. Large entry air locks would be installed to introduce or remove equipment along with a large sealed staging area. The area between the large
overhead doors into the reactor building leading to the nearby large equipment hatch into containment is the planned location for this system.
The above diagrams show various methods for installing sealed entryways into containment along with the introduction routes and removal routes for equipment or radioactive materials.
Containment Sealing NDF and the affiliated decommissioning groups have been working on ways to seal all of the penetrations into containment for the purpose of flooding the containment structures in the future. This flooding concept is problematic. The containment structures were not designed to include full flooding with water. Concerns about how this would impact their stability and ability to withstand an earthquake remain. There are also concerns what would happen if the containment structures were to leak after flooding, releasing highly contaminated water and fuel debris. Research into plugging the suppression chamber downcomer tubes with various polymers has been ongoing for years. This research has had mixed results. There has also been research into plugging the other structures of the torus tube such as vacuum breaker pipes. Yet another concept included pouring concrete into the torus tube to solidify and seal that area.
The many small penetrations into the containment structure also pose a problem. These were originally part of the design to allow probes and sensors to be introduced into the containment structure during operation or to bring equipment into containment during refueling. Many others allow the multitude of pipes to pass through the containment walls. All of these would need to be resealed in a way that could withstand the water pressure of a flooded containment structure and not fail or leak.
Radiation Control During Decommissioning The mid-term and long term risks of the fuel debris (corium) is a significant problem related to any decommissioning activities at Fukushima Daiichi. The fuel debris can generate hydrogen, break apart and leak out of the building and if it manages to reach the proper configuration it can go critical. Higher risk debris is being considered as a priority. They didn’t clarify clearly but debris that could break apart and any debris with a high content of uranium would be of the highest risk. In addition to prioritizing the removal of fuel debris, reducing the radiation exposure of workers is a balancing priority. While this work needs to be done it needs to be done in ways that make worker exposures as low as possible.
New Containment Access The decision for how fuel may be removed in each unit is based upon the condition of the RPV (reactor pressure vessel), how much fuel resides in the reactor pedestal and how much fuel debris resides elsewhere. Fuel debris outside the pedestal or burned down into the basemat concrete may require some of the alternative methods of fuel retrieval. RPV investigations, further containment investigations and confirmation of all of the leak paths out of containment for each unit will be needed to further determine the fuel removal method to be used. Fuel Removal Location Options - Top (flooded, not flooded) - Sides - Below (new)
The standard three plans for retrieving fuel debris (above). All are dependent on the bulk of the fuel being inside the reactor pedestal.
Methods that retrieve fuel from above will require an additional contained and shielded structure due to high radiation levels. This would prevent releases to the environment and exposures to workers and equipment.
This internal system (above) would be used to remove any remaining fuel debris inside the reactor vessel. It may have the capability to retrieve some of the fuel remaining in the pedestal region.
This mockup (above) shows how a retractable system could be used to remove fuel from a side location without water flooding. This is dependent on the “hot cell� entrance and control system mentioned earlier.
Further detail of the steps the side system would use to retrieve fuel in the pedestal. This would only be capable of removing fuel burned partially down into the basemat. If fuel is deeply burned down into the basemat or completely through the basemat, other methods would be required.
A new concept was quietly published by NDF in 2016 and overlooked by the press. This new concept tunnels deeply below the reactor building from the landside area of the plant and then tunnels up into the containment structure from below. This method would be applicable if they find fuel has burned deeply down into the basemat or into the soil below the reactor building.
This machine translation of the NDF report diagram (above) shows what appears to be similar to a large underground tunnel system. Similar sealed tunnel systems for civil structures like BART transit in San Francisco or the Chunnel train system between Britain and France may provide the basis for this concept. Both of these existing systems operate sealed tunnels under bodies of water. That level of capability would be needed at Fukushima Daiichi due to the high groundwater levels.
The above diagram from the NDF report shows proposed entry and exit points along with tunnel routes as they would traverse through the frozen wall.
This machine translation of an NDF diagram explains the concept with more detail along with the challenges involved. Contamination will be a considerable challenge that would require ongoing control measures.
This machine translated diagram shows more detail of the proposed control system below the reactor building.
Fuel Removal Technology Fuel debris removal technology is unique to the type of debris being removed. What overall method would be used at each unit is dependent on the existing damage to that unit and what process may be the easiest to implement. The factors that direct what approach to use include the amount, location and composition of the fuel debris (corium). The condition of the RPV (reactor pressure vessel) and the control rod drive system that resides below the RPV. The conditions within the pedestal area below the reactor vessel and the amount of fuel that may be located there will also impact the approach. NDF documents did admit that there is the potential for the concrete pedestal structure to have been damaged by the meltdowns. One such scenario included the corium eroding the concrete at the base of the pedestal, weakening it.
Radiation levels also impact how work will be conducted. Fuel particles (FP) are a concern, these are mobile small pieces of nuclear fuel or highly radioactive particles that were created by the meltdowns. NDF cites the need for further investigation into the specific conditions within the containment structures and also continuing research to estimate conditions.
Various types of industrial cutting tools being considered for fuel debris removal.
Designs underway of an articulating arm that could be used to cut apart fuel debris. These designs rely heavily on hydraulics rather than electronics due to the high radiation levels.
Waste Fuel & Debris Storage The planned process for fuel and other highly radioactive debris storage relies on existing experience from Three Mile Island and attempts to apply that knowledge to Fukushima Daiichi. A storage canister capable of holding and shielding highly radioactive debris is being researched using the canisters used at TMI as a starting point. The diagram below shows the workflow process for removing fuel debris inside the reactor through to storing those canisters.
This work will also require the construction of new high level nuclear waste storage facilities at Fukushima Daiichi. Special security measures will be put in place to comply with nonproliferation rules on nuclear materials and to prevent acts of sabotage or terrorism.
The above diagram from NDF shows the start to finish process of placing fuel debris in canisters and removing it for storage. A similar process under less demanding conditions was used to remove fuel debris from the Three Mile Island reactor.
Filter Storage Storage of filters from the existing contaminated water filtration systems is housed up on the hill at the Fukushima Daiichi disaster site with highly radioactive filter canisters stored in concrete cells that are remotely handled by overhead cranes. This will need to be expanded over time. It will also need to include filters from containment filtration systems required during fuel debris removal. This may be the most dangerous type of waste storage on site besides spent fuel and the fuel debris itself. Certain stored filters were found to be generating hydrogen. Additional monitoring was implemented but this highlighted the long term risks of storing these materials.
Waste Storage General waste storage continues around the elevated areas of the site. Covered buildings and warehouses have popped up around the grounds to house various types of debris from all of the work on site. This will be a long term challenge as room is needed for more high level contaminated material storage.
Contaminated Water TEPCO has continued with the process of removing all of the old bolt together tanks while installing new welded tanks in the same areas and some adjacent new areas. Old tanks are remotely processed into smaller pieces then stored as high level nuclear waste. This work may be ongoing for the next couple of years. The old bolt together tanks were found to be leaking in previous years, requiring their removal and replacement.
Worker Safety Decontamination efforts have been ongoing in an attempt to reduce the amount of radiation workers are exposed to. These have included paving over large sections of the site. Some areas now require only coveralls and a paper face mask, those are mostly uphill from the reactor buildings. Areas near the reactors themselves still requires a radiation suit and full face respirator. Improved rest areas and a new on site building for staff coordination and food service was constructed to make long term work on site more efficient. This also consolidates some of the temporary facilities on site.
The work conducted on site is still not without considerable risk. Mainichi points out the challenges of the inspection work done inside unit 2 recently. The work is hot, difficult to do in the restrictive equipment and on tight time constraints to prevent exposure. Even the most basic work can become a challenge.
Workers participating in the disassembly of the bolt together water tanks received higher than expected radiation exposures. Some of these workers received radiation exposures to their eyes of over 75 mSv. This increases the risk of radiation induced cataracts. 7 Fukushima workers who were part of the Fukushima 50 that battled the meltdowns were found to have radioactive glass micro-particles in their lungs. These insoluble particles lodged in the lung will cause these workers long term radiation exposures. Another worker dropped dead at the plant in 2016. In July a worker was found unconscious in the administration building and was confirmed dead at the Iwaki hospital. A cause of death has not been made public. This last year also saw the first worker suits for cancers related to their work at the site. 15 workers so far have cases pending for cancers including thyroid cancer, leukemia and others. A worker who drove heavy equipment used to scrape away the debris from the reactor explosions has filed a compensation suit. He rapidly developed cancers of the bladder, stomach and colon cancer after his high risk work at the plant.
These reports do not include all workers who may have contracted a cancer related to their exposure. Only the ones that have made it to an administrative or court hearing have made the press. More may be in the works so the total number of workers who have contracted a work related cancer to date is not known. Other injuries such as cataracts and other documented types of radiation related health damage may also begin showing up as workers compensation cases in the near future.
Wildlife & Monsters Previous years saw more problems with wildlife at the plant including fox, tanuki, dogs and random activists. This year the problems were more digital. Pokemon began showing up at the disaster site. TEPCO asked Niantic to remove the virtual monsters from the plant. They had concerns with the potential of workers playing on the site grounds or the public coming on site in search of Pokemon.
Frozen Wall & Ground Water Control The frozen wall has progressed but any declaration of it being a success has been elusive. Most of the wall is now frozen. Locations along the landside were left unfrozen to allow some groundwater to flow into the controlled area. The system uses a considerable amount of power. A new building and new incoming power lines were installed on site to deal with this demand.
The diagram below shows the progress and where the wall has been left un-frozen. Most of the problems forcing the wall to freeze involved an area north of unit 1 where there is a strong groundwater current and a leak from unit 1’s turbine building. South of unit 4 found a similar problem where freezing challenges persisted. TEPCO injected quick drying concrete below ground in these areas in the summer of 2016. Over time this appears to have assisted the freezing process. The contamination monitoring intended to document the improvements of the frozen wall did not see the kind of progress that was expected. Near shore contamination has remained largely unchanged. Sea front wells saw a small amount of improvement but not as much as expected. There are concerns that contaminated water may be leaking out to sea beneath the frozen wall. It is also not completely conclusive that the wall is forming a solid barrier and instead may be just acting to slow the amount of groundwater leaving the plant.
At the same time TEPCO has been attempting to lower the remaining water levels inside the reactor building basements and turbine buildings. All water pumped out of the subdrain pit system near the reactor buildings or from the building basements is then sent through the contaminated water treatment systems.
Room for incoming contaminated water has been created by filtering then dumping lesser contaminated water into the sea. Most radioactive contamination is removed first but tritium and some other isotopes remain. The water is diluted or filtered until it is below international limits before it is dumped. This water legally complies with set standards but is still a contamination of the ocean done over time. Another problem created by the various attempts to prevent contaminated water from leaking out of the reactor areas of the plant was a sudden rise of groundwater and flooding in fall of 2016. Heavy rains caused the localized groundwater near the sea front to rise. Wells rose and standing water was seen in the area. Over the winter this year has been dry but this problem may show up again in the spring or when large volumes of water are deposited in the area from tropical storms.
Decommissioning R&D Facilities A number of new facilities have been constructed to deal with the research and development work required for decommissioning activities at Fukushima Daiichi.
Onahama training center This area of the Onahama port in Iwaki has been used as a staging area by TEPCO since the disaster. The unit 3 cover building mock up can be seen in the above photo. Little formal information about this facility is provided except for random mentions in reports.
JAEA Okuma Training Center This facility is planned to open in 2017. The site, adjacent to Fukushima Daiichi will conduct fuel debris research, and other research related to dealing with the fuel debris.
Naraha Remote Technology Research Center This facility focuses on testing robotic equipment and similar remote technologies for use at Fukushima Daiichi. It provides a safe environment to determine the ability of robots and other equipment before attempting work in the high radiation environment. The Naraha facility also includes the virtual reality suite used to explore areas of the reactor building using 3D data collected by robots in the reactor buildings.
The Naraha facilities include large scale mock up facilities for the construction of scale models of various structures from the reactor buildings for testing purposes.
ENVIRONMENTAL A planned facility near Fukushima Daiichi that would house the massive stockpiles of contaminated soil has been pushed back until 2020. Problems with the sale or lease of land from the original landowners and other logistical problems have created the delays. A fire at a soil and debris storage site in Namie highlighted the risks of having all of these bags of soil and plant debris piled up around the country.
There was also the strange case of a murdered decontamination worker. Police arrested the president of the construction company and 6 workers from the same company. No motive for the worker’s murder has been given to the press. Cesium 137 contamination that flowed into the Pacific Ocean since 2011 will begin to circulate back across the Pacific and will show up in Japanese waters in the next 2-3 years according to oceanography experts. Increases in contamination began showing up near the North American coasts as early as 2014. Another research paper was published documenting micro-particles of fused reactor materials including substances from the reactor fuel. The new finding documented these substances being found in Tokyo. This is the furthest such materials have been found from the disaster site, where the relocation of the materials is assumed to be by environmental means. Fukushima grown rice is back on the market with a brand being sold in London. Conger and flounder fish from Fukushima were allowed back on the retail market in Japan. A smuggling ring that brought crab and other seafood hauled in Fukushima to China was busted by authorities. The complicated crab laundering operation sent the seafood to Hokkaido, then to Vietnam
before being sent to China. From there it was distributed to the domestic markets and potentially exported from there to points unknown. Radioactive boar have become another long term problem in Fukushima prefecture and beyond. The boar are encroaching on the evacuated areas, causing damage. They also tend to be highly radioactive due to their eating habits. Culling the animals has presented another problem, what to do with their radioactive carcasses.
Humanitarian Issues Evacuees The extent of the harassment evacuees have experienced became clear in the last year after a highly publicized incident of school bullying, involving a student who was a Fukushima evacuee. Asahi Shimbun conducted polling of evacuees related to their experiences with bias, harassment and bullying. 60% of the respondents had either been directly bullied, witnessed or were told of others being bullied. Some of the incidents described have been threatening and significantly intimidating. Others were more insidious insults of the individual’s place in society. This has caused many of the respondents to hide that they are evacuees out of fear of discrimination. The professor who conducted the survey pointed out that the evacuees are not always recognized as victims of the disaster, leading to their bullying and harassment. As of September, 2016, 90,000 evacuees remained in temporary housing. 45,832 of those still live in the shipping container style temporary housing units. Construction of new permanent housing has been purposely delayed to prod more evacuees into returning to the contaminated zones in Fukushima. The towns of Namie, Iitate, Kawamata and Tomioka are all set to reopen soon. These areas include some of the most radioactive areas of the evacuation zone. Towns that previously reopened are seeing few residents return. By now many have set up home elsewhere. The lack of essential services and the persistent radiation levels have contributed to people opting to not return. Katsurao town was reopened in June, 2016. The town has annual radiation exposure levels of 20-50 mSv/year. The maximum annual exposure for a nuclear worker in most countries is 20 mSv/year.
Health 7 workers that were found to have inhaled radioactive glass micro-particles raise concerns about the same risk to the general public. These types of fused insoluble radioactive microparticles have been found around the evacuation zone and as far away as Tokyo. The environmental findings of these particles indicate that some are small enough to be inhaled. This risk to the public remains unaddressed. There are now 184 confirmed or suspected cases of thyroid cancer among children participating in the Japanese government monitoring program. One new case was added on the newest report. Many of these now confirmed cancers showed with no problems on previous ultrasounds indicating that the radiation exposure these individuals received is the likely cause of their cancers.
Costs To date the triple disaster has cost Japanese taxpayers 100 billion USD as of early 2016. Costs for the disaster site and contaminated soil management are being shifted away from TEPCO and onto the taxpayers. The costs for dealing with over 9 million bags of contaminated soil may also fall onto the taxpayers.
Conclusions In six years, in some ways little has changed. The disaster site at Fukushima Daiichi still lacks a detailed realistic plan to deal with the technical challenges. Personal lives are still upended and may be for the long term. The solutions provided by the government involve returning to contaminated and still decimated communities or starting over from scratch somewhere else with little help. The environmental challenges persist. Cleaning up large swaths of land to predisaster levels was never an achievable task. Instead people have been asked to accept radioactive contamination into their daily lives. Natural redistribution of contamination and radioactive decay have been heralded as successes in improving the environment by the government yet much of the contamination will never truly go away. Health problems have begun to be undeniable as more people develop new cancers that can be tied to their radiation exposure. Over time the probability of other cancers will increase in the exposed populations. At the same time the government has been keen to dismiss the growing number of health problems as not related to the disaster. Time will tell. The disaster is not unique to Japan. This kind of disaster could happen anywhere. You only need enough disruption and damage to make cooling a nuclear reactor impossible for a few hours.
Will the disaster site at Fukushima Daiichi ever be cleaned up? That remains to be seen. The technical challenges are immense. Technology must be invented to deal with the conditions at the plant. Many times it has to be modified or re-evaluated on the fly as new challenges show up. Just giving up is not an appropriate response. The next year could be pivotal in determining the direction of Fukushima Daiichi and also the impacted populations. Deadlines for detailed decommissioning plans are looming. Compensation and assistance programs are nearing end dates. What happens next will set important paths for the future. We hope the paths taken are wise ones.
Bibliography SimplyInfo.org Fukushima Daiichi Unit 2 Extended Report 2015 February 23, 2015 http://www.fukuleaks.org/web/?p=14318 Fukushima Unit 2 Containment Inspection Starts Jan 18th Published 1.17.2017 http://www.fukuleaks.org/web/?p=16020 Fukushima Daiichi Floods, Shows Lack Of Preparedness September 22, 2016 http://www.fukuleaks.org/web/?p=15765 15 Fukushima Workers Have Cancer January 18, 2017 http://www.fukuleaks.org/web/?p=16025 Interim Fukushima Contaminated Soil Storage Won’t Start Until 2020 March 26, 2016 http://www.fukuleaks.org/web/?p=15386 Fukushima Disaster Costs Taxpayers $100 Billion So Far March 7, 2016 http://www.fukuleaks.org/web/?p=15370 Fire At Namie Nuclear Waste Site March 6, 2016 http://www.fukuleaks.org/web/?p=15364 Fukushima Workers Removing Tanks Receive High Radiation Exposures April 18, 2016 http://www.fukuleaks.org/web/?p=15434 5 At TEPCO Home Office Knew Of Meltdown Manual May 13, 2016 http://www.fukuleaks.org/web/?p=15504 Fukushima Pacific Contamination Will Show Back Up In Japan 2-3 Years May 11, 2016 http://www.fukuleaks.org/web/?p=15467 Fukushima Decontamination Company Employees Arrested For Murder May 17, 2016 http://www.fukuleaks.org/web/?p=15480 Fukushima Radioactive Glass Microparticles In Tokyo Confirm Other Findings June 29, 2016 http://www.fukuleaks.org/web/?p=15585
Bibliography Fukushima Rice To Be Sold In London June 24, 2016 http://www.fukuleaks.org/web/?p=15572 TEPCO Admits To Cover Up Of Meltdowns At Fukushima Daiichi June 21, 2016 http://www.fukuleaks.org/web/?p=15563 DPJ May Take Legal Action Against TEPCO For Meltdown Scandal June 18, 2016 http://www.fukuleaks.org/web/?p=15552 Highly Radioactive Fukushima Town Reopens June 13, 2016 http://www.fukuleaks.org/web/?p=15537 Govt. To Allow Two Fukushima Fish Species To Be Sold June 12, 2016 http://www.fukuleaks.org/web/?p=15522 Another Worker Drops Dead At Fukushima Daiichi July 31, 2016 http://www.fukuleaks.org/web/?p=15653 Pokemon Go: Don’t try and catch creatures in the Fukushima disaster zone, trainers told July, 2017 http://www.independent.co.uk/life-style/gadgets-and-tech/gaming/pokemongo-fukushima-japan-dangers-radioactive-zone-concerns-a7158141.html Pokemon Spotted At Fukushima Daiichi July 26, 2016 http://www.fukuleaks.org/web/?p=15627 Radioactive Glass Found In Lungs Of Fukushima Workers July 21, 2016 http://www.fukuleaks.org/web/?p=15616 90000 Still In Temporary Housing After Fukushima Disaster September 17, 2016 http://www.fukuleaks.org/web/?p=15745 Fukushima Radioactive Boar Create New Problems December 31, 2016 http://www.fukuleaks.org/web/?p=16003 Public To Shoulder Fukushima Decontamination Costs While Waste Piles Up December 21, 2016 http://www.fukuleaks.org/web/?p=15982
Bibliography Fukushima Thyroid Examination February 2017: 184 Thyroid Cancer Suspected/Confirmed (1 Additional Case) February 24, 2017 http://fukushimavoice-eng2.blogspot.com/2017/02/fukushima-thyroidexamination-february.html Ex-worker at Fukushima nuclear plant seeks compensation for cancer February 28, 2017 http://english.kyodonews.jp/news/2017/02/461083.html SIX YEARS AFTER: 4 more districts in Fukushima set to be declared safe to return to February 28, 2017 http://www.asahi.com/ajw/articles/AJ201702280051.html Proud workers at Fukushima No. 1 nuke plant risk deadly radiation danger February 27, 2017 http://mainichi.jp/english/articles/20170227/p2a/00m/0na/007000c SIX YEARS AFTER: 60 percent say Fukushima evacuees bullied February 26, 2017 http://www.asahi.com/ajw/articles/AJ201702260027.html The hidden costs households must pay for nuclear disaster in 2011 February 27, 2017 http://www.asahi.com/ajw/articles/AJ201702270056.html Japan’s $320 Million Gamble at Fukushima: An Underground Ice Wall August 29, 2016 https://www.nytimes.com/2016/08/30/science/fukushima-daiichi-nuclearplant-cleanup-ice-wall.html?_r=0 Fukushima Seafood Smuggling Ring Busted In China August 22, 2016 http://www.fukuleaks.org/web/?p=15699
Bibliography CLADS Laser research http://fukushima.jaea.go.jp/english/topics/pdf/topics-fukushima070e.pdf Naraha research center http://fukushima.jaea.go.jp/english/topics/pdf/topics-fukushima068e.pdf Okuma research center & Naraha research http://www.meti.go.jp/english/earthquake/nuclear/decommissioning/hairotor ikumi.html Japan Atomic Energy Agency (JAEA) https://www.jaea.go.jp/english Nuclear Damage Compensation and Decommissioning Facilitation Corporation http://www.dd.ndf.go.jp/eindex.html Three Mile Island Storage Canisters - US Nuclear Regulatory Commission 2001 https://www.nrc.gov/docs/ML0708/ML070820571.pdf
Credits Many thanks to the SimplyInfo.org research team that made this report possible and their 6 years of tireless research. Most photos within the report are credit TEPCO. Copyright 2017 SimplyInfo.org