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

” 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. ”

by Beyond Nuclear

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Work to finish ice wall at crippled plant to begin — NHK World

” The operator of the crippled Fukushima Daiichi nuclear plant will begin the final phase of creating an underground ice wall on Tuesday.

Tokyo Electric Power Company started the work 17 months ago, with the aim of preventing groundwater from entering reactor buildings and getting contaminated with radioactive substances.

The 1.5-kilometer ice barrier is deemed a key step to curb the buildup of tainted water at the plant.

The soil is frozen by sending liquid at minus 30 degrees Celsius into pipes buried around the buildings. But the utility has left a 7-meter section unfrozen, fearing the sudden fall in groundwater levels around the buildings.

There were concerns that the difference of water levels in and outside the reactor buildings would cause tainted water inside to leak out.

But last Tuesday, the Nuclear Regulation Authority said safety measures are ready and gave its approval to freeze of the final section.

Officials of the utility say they will carefully monitor the freezing process of the remaining section.

They say it may take longer to fully freeze than other areas, because the flow of groundwater has been concentrated in that section.

The officials expect that the wall, when completed, will reduce the inflow of groundwater to the buildings from 140 tons a day to less than 100 tons. ”

by NHK World

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Minister opposes releasing treated water from Fukushima plant into sea — The Mainichi

According to The Georgia Straight, plans to dump tritium-contaminated waste water into the Pacific Ocean have been cancelled.

The Mainichi: ” TOKYO (Kyodo) — Japan’s disaster reconstruction minister said Friday he is opposed to treated water from the disaster-struck Fukushima Daiichi nuclear power plant being released into the sea, citing the possible repercussions for local fishermen.

Masayoshi Yoshino’s remarks came shortly after a top official from plant operator Tokyo Electric Power Company Holdings Inc. said he is ready to see the tritium-containing water dumped into the sea.

A government panel is still debating how to deal with the water stored in tanks at the plant where three nuclear reactors melted down in the days after a huge earthquake and then tsunami struck the region in 2011.

Tritium is a radioactive substance considered relatively harmless to humans. It remains in the filtered water as it is difficult to separate even after passing through a treatment process. At other nuclear power plants, tritium-containing water is routinely released into the sea after it is diluted.

Yoshino expressed at a news conference his concerns over the potential ramifications of releasing the treated water into the sea, saying there would “certainly be (perception) damage due to unfounded rumors.”

The minister urged those pushing for the release of the water “not to create fresh concerns for fishermen and those running fishing operations in Fukushima Prefecture.” He also asked them “not to drive (fishermen) further towards the edge.”

He was alluding to concerns among local fishermen about the effects on their livelihood if the public perceives fish and other marine products caught off Fukushima to be contaminated.

Takashi Kawamura, chairman of Tepco, said in a recent interview that the decision to discharge the treated water “has already been made.”

After Kawamura’s remarks were widely reported, the utility was forced to make a clarification through a statement on Friday. Tepco said its chairman meant to say there is “no problem (with releasing water containing tritium) according to state guidelines based on scientific and technological standpoints,” and that the decision to release is not yet final.

While the plant operator and the Ministry of Economy, Trade and Industry want to discharge the water, the local fishermen, backed by the minister, are opposed to it.

At the Fukushima plant, water becomes toxic when it is used to cool the damaged reactors. It is treated through a process said to be capable of removing 62 different types of radioactive material, except tritium.

Yoshino said Friday that while he is aware of some scientists’ opinion that the water should be released after it is diluted to permissible levels, he is not in favor of the idea.

“As I am also a native of Fukushima Prefecture, I fully understand the sentiment of the people,” Yoshino said. However, the minister has no authority to decide how the treated water will be disposed.

An ever-increasing amount of water containing tritium is collecting in tanks at the Fukushima plant. As of July 6, approximately 777,000 tons were stored in about 580 tanks.

On March 11, 2011, water inundated the six-reactor plant, located on ground 10 meters above sea level, and flooded power supply facilities. Reactor cooling systems were crippled and the Nos. 1 to 3 reactors suffered fuel meltdowns in the world’s worst nuclear catastrophe since the 1986 Chernobyl disaster. “

by The Mainichi

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Poison in the air — The New International, Opinion

” Three of the six reactors at Japan’s Fukushima-Daiichi complex were wrecked in March 2011 by an earthquake and tsunami. The destruction of emergency electric generators caused a ‘station blackout’ which halted cooling water intake and circulation. Super-heated, out-of-control uranium fuel in reactors 1, 2, and 3 then boiled off cooling water, and some 300 tons of fuel ‘melted’ and burned through the reactors’ core vessels, gouging so deep into underground sections of the structure that to this day operators aren’t sure where it is. Several explosions in reactor buildings and uncovered fuel rods caused the spewing of huge quantities of radioactive materials to the atmosphere, and the worst radioactive contamination of the Pacific Ocean ever recorded. Fukushima amounts to Whole-Earth poisoning.

Now, researchers say, radioactive isotopes that were spread across Japan (and beyond) by the meltdowns will continue to contaminate the food supply for a very long time.

According to a new study that focused on ‘radiocaesium’ – as the British call cesium-134 and cesium-137 – ‘food in japan will be contaminated by low-level radioactivity for decades’. The official university announcement of this study neglected to specify that Fukushima’s cesium will persist in the food chain for thirty decades. It takes 10 radioactive half-lives for cesium-137 to decay to barium, and its half-life is about 30 years, so C-137 stays in the environment for roughly 300 years.

The study’s authors, Professor Jim Smith, of the University of Portsmouth, southwest of London, and Dr. Keiko Tagami, from the Japanese National Institute of Radiological Sciences, report that cesium-caused ‘radiation doses in the average diet in the Fukushima region are very low and do not present a significant health risk now or in the future’.

This phraseology deliberately conveys a sense of security – but a false one. Asserting that low doses of radiation pose no ‘significant’ health risk sounds reassuring, but an equally factual framing of precisely the same finding is that small amounts of cesium in food pose a slightly increased risk of causing cancer.

This fact was acknowledged by Prof Smith in the June 14 University of Portsmouth media advisory that announced his food contamination study, which was published in Science of the Total Environment. Because of above-ground atom bomb testing, Prof. Smith said, “Radioactive elements such as caesium-137, strontium-90 and carbon-14 contaminated the global environment, potentially causing hundreds of thousands of unseen cancer deaths”.

No less an authority than the late John Gofman, MD, Ph D, a co-discoverer of plutonium and Professor Emeritus of molecular and cell biology at the University of California, spent 50 years warning about the threat posed by low doses of radiation. In May 1999, Gofman wrote, “By any reasonable standard of biomedical proof, there is no safe dose, which means that just one decaying radioactive atom can produce permanent mutation in a cell’s genetic molecules. My own work showed this in 1990 for X rays, gamma rays, and beta particles.”

The Fukushima-borne cesium in Japan’s food supply, and in the food-web of the entire Pacific Ocean, emits both beta and gamma radiation. Unfortunately, it will bio-accumulate and bio-concentrate for 300 years, potentially causing, as Dr Gofman if not Dr Smith might say, hundreds of thousands of unseen cancer deaths. ”

originally published in CounterPunch

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Radiation levels exceeding state-set limit found on grounds of five Chiba schools — The Japan Times

” Radiation levels exceeding the government-set safety limit of 0.23 microsieverts per hour have been detected on the grounds of five schools in the city of Kashiwa, Chiba Prefecture, the prefectural board of education said Monday.

Between late April and mid-May, the board officials detected radiation levels of up to 0.72 microsieverts per hour in certain areas of the schools, including Kashiwa High School and Kashiwa Chuo High School. The areas — including soil near a school swimming pool and drainage gutters — are not frequented by students, but the board closed them off and will work to quickly decontaminate them, the officials said.

Kashiwa has been one of the areas with high radiation readings since the 2011 nuclear disaster at Tokyo Electric Power Company Holdings Inc.’s Fukushima No. 1 power plant.

According to NHK, the board of education had been checking the soil on the school premises in Kashiwa after radiation levels beyond the state limit were detected in shrubbery near the city’s public gymnasium. The board will announce the results of radiation tests at other schools in the prefecture around the end of July, NHK reported. ”

by Kyodo, The Japan Times

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Nuclear taxes get new lease on life after Fukushima — Nikkei Asian Review

” OSAKA — Japanese prefectures with nuclear power plants are moving to ensure that utilities continue to shoulder a tax burden on reactors even as they are being decommissioned, dramatically raising the cost of cleanup efforts that can last 30 to 40 years.

Five nuclear reactors have been approved for decommissioning since the 2011 meltdowns at Tokyo Electric Power Co. Holdings’ Fukushima Daiichi plant. In each case, the host prefectural government has received approval from the ministry of internal affairs to apply a nuclear tax during decommissioning.

Ehime Prefecture in western Japan, home to Shikoku Electric Power’s Ikata nuclear power plant, has decided to change its ordinances by the fall to enable it to collect taxes on the plant’s No. 1 reactor. Shikoku Electric decided last May to decommission the reactor and has applied to the Nuclear Regulation Authority for approval.

The continued stream of tax revenue will help the Ehime government maintain evacuation routes and other facilities and safety measures until the reactor is fully dismantled and nuclear contamination risks eliminated.

Revenue generator

Of the 13 prefectures that host reactors, only Fukushima does not levy a nuclear fuel tax. Prior to the disaster, most prefectures did not collect these taxes during periods when reactors were shut down for periodic inspections or other reasons. The handful of reactors marked for decommissioning before the disaster have not had their taxes extended.

However, prolonged nuclear power plant shutdowns since Fukushima have prompted local governments to tax reactors based on output capacity even when they are idle to try to wring revenue out of idle units. The moves to extend taxes into decommissioning mark a further step.

Ehime Prefecture’s nuclear fuel tax generated 1.46 billion yen ($13.1 million) in revenues to the government in fiscal 2016, 264 million yen of which came from the inactive No. 1 unit at the Ikata power plant. The government seeks to collect at least half of the full amount during decommissioning.

Fukui Prefecture, home to three reactors approved for decommissioning, expects to collect an annual 370 million yen in revenues from its revised nuclear tax, which comes to half of the standard level.

With the country’s nuclear regulator imposing an in-principle 40-year operating limit on reactors, decommissionings are expected to continue at a pace of one to two units a year. The costs of taking a reactor out of service and rendering the site safe are generally estimated at tens of billions of yen. The tax burden could add up to billions of yen per reactor over the course of decommissioning.

“While the taxes may have benefits for communities, if electric rates go up as utilities’ costs rise, residents will also feel the burden,” said Tatsujiro Suzuki, an authority on nuclear energy policy at Nagasaki University. ”

by Nikkei Asian Review

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