Until the Fukushima accident, Japan had 55 operating nuclear reactors as well as enrichment and reprocessing plants which had suffered a series of deadly accidents at its nuclear facilities resulting in the deaths of workers and releases of radioactivity into the environment and surrounding communities. Since the Fukushima disaster, there is growing opposition against re-opening those reactors closed for maintenance.



Fukushima’s decommissioning delays, challenges and unknowns remain roadblocks to cleanup

Six and a half years after the Fukushima Daiichi triple meltdown, Japan’s government, the nuclear regulator and Tokyo Electric Power Company’s (TEPCO) most rudimentary plan of attack for recovery from radioactive catastrophe is delayed again. The first steps of decommissioning cannot legitimately begin until undamaged but highly radioactive “spent” fuel assemblies are removed from vulnerable reactor storage ponds, sufficiently cooled and re-contained in qualified dry storage casks.  Then, there are the three melted fuel cores that still must be located, retrieved and somehow re-contained. Where all of the massive radioactive contamination will go is a mystery.  In fact, there are an alarming number of challenges, continuing delays and unknowns that remain before securing the destroyed nuclear power station site and halting the ongoing release of radioactivity to the land, water and air.

Among the most immediate concerns is the management of 1007 highly radioactive and thermally hot irradiated nuclear fuel assemblies still in the two cooling pools perched atop the destroyed Units 1 and 2 outside of any containment structure. Each of the site’s six-units has an elevated nuclear waste storage pond. The site has a large common pool located near Unit 4. The government recently admitted that previously unknown, possibly undisclosed, damage in these irradiated fuel storage ponds and radioactive contamination has again delayed the plan to move the dangerous fuel assemblies by at least another three years, now 2023. Unit 3 remains on schedule in 2018 to begin the two-year transfer of 514 irradiated fuel assemblies from its rooftop storage pool to a jam-packed common onsite pool located at ground level. This common pool and its massive radioactive inventory requires reliable cooling power.  Unit 4 completed a three-year project to transfer its irradiated fuel into the common pool in 2014. The common pool now has 6,726 irrradiated fuel assemblies with a maximum design capacity of 6,840. As this common pool is already densely packed, it is ever more critical that Japan expedite the transfer of the sufficiently cooled irradiated nuclear fuel into qualified, individualized dry storage casks that can passively cool the hot nuclear waste without the need for water and electrical power. Currently, only 1,412 irradiated assemblies have been secured in onsite dry cask storage. These dry casks further need to be hardened against another natural disaster and possible terrorism. 

The recurring delays at securing the irradiated fuel currently in wet pool storage (individual units to the common pool) and then into scientifically-qualified and hardened dry cask storage systems raises concern for public health, safety and the environment given the prospect of another large nearby earthquake causing a loss of cooling with the risk of a nuclear waste fire and radioactive releases. A 6.9 magnitude offshore earthquake on November 21, 2016 caused a temporary loss of cooling to wet storage systems at Fukushima Daiichi. Significant earthquakes of 6.0 to 6.9 magnitude occur in Japan on average 17 times per year, roughly one-tenth of all large earthquakes in the world. More severe earthquakes must be anticipated. The loss of cooling power and water to some or all of the more than 11,577 hot nuclear waste assemblies onsite outside of containment remains a significant public health, safety and environmental concern.

Japan is still technologically conceptualizing the “most challenging part” of Fukushima Daiichi’s decommissioning and the recovery of three missing melted reactor cores if and when they can be located. The unprecedented operation has now been delayed until 2019.  A viable technology for scooping up melted nuclear fuel does not yet exist. Re-containment and removal of the melted fuel cores is key to addressing the ongoing massive buildup of radioactive water now estimated at 800,000 tons that is being stored in growing onsite tank farms.  Groundwater flowing down into the reactor wreckage must be constantly pumped out, partially filtered of radioactivity and stored onsite in the large tanks. The tank farms themselves represent an additional environmental threat in the event of another severe earthquake that could rupture the structures with a radioactive flood into the ocean.  


Beyond Nuclear on Thom Hartmann: Is Fukushima still melting down?

Beyond Nuclear's Kevin Kamps appeared on Thom Hartmann's "The Big Picture" to discuss the discovery, 6.5 years later, of melted core at Fukushima Daiichi Unit 3, as well as Tokyo Electric Power Company's threat to simply release 770,000 metric tons (around 200 million gallons) of very highly tritium-contaminated wastewater directly into the Pacific Ocean.


5 workers exposed to radiation at Japan nuclear lab

As reported by AP:

Five workers at a Japanese nuclear facility that handles plutonium have been exposed to high levels of radiation after a bag containing highly radioactive material apparently broke during equipment inspection, the country's Atomic Energy Agency said Wednesday.

The incident occurred Tuesday at its Oarai Research & Development Center, a facility for nuclear fuel study that uses highly toxic plutonium. The cause of the accident is under investigation, the state-run agency said. It raised a nuclear security concern as well as a question whether the handlers were adequately protected.

The agency said its initial survey found contamination inside the nostrils of three of the five men — a sign they inhaled radioactive dust. All five were also found to be contaminated on their limbs after removing protective gear and taking a shower, which would have washed off most contamination.

Agency spokesman Masataka Tanimoto said one of the men indicated high levels of plutonium exposure in his lungs, with the dose showing nearly 1,000 times that of his earlier nostril survey.

Internal exposure poses a bigger concern because of its potential cancer-causing risks. The figure, 22,000 Becquerels, could mean exposure levels in the lungs may not be immediately life-threatening.

But an inhalation dose of ultra-hazardous plutonium carries a high-risk for eventual lung cancer. The latency period could extend years or even decades.


Trove of medical records snapshot of doctors’ plight after Fukushima


Naraha sees three schools return from nuclear exile in Fukushima