Is it safe to dump Fukushima waste into the sea? — The Guardian; Inquisitr

” More than 1,000 tanks brimming with irradiated water stand inland from the Fukushima nuclear plant. Each day 300 tonnes of water are pumped through Fukushima’s ruined reactors to keep them cool. As the water washes through the plant it collects a slew of radioactive particles.

The company that owns the plant – The Tokyo Electric Power Company (Tepco) – has deployed filtration devices that have stripped very dangerous isotopes of strontium and caesium from the flow.

But the water being stored in the tanks still contains tritium, an isotope of hydrogen with two neutrons. Tritium is a major by-product of nuclear reactions and is difficult and expensive to remove from water.

Now, Japan’s Nuclear Regulation Authority (NRA) has launched a campaign to convince a sceptical world that dumping up to 800,000 tonnes of contaminated water into the Pacific Ocean is a safe and responsible thing to do.

NRA chairman Shunichi Tanaka has officially called on Tepco to work towards a release. The International Atomic Energy Agency (IAEA) last year also issued a call for a release to be considered and for Tepco to perform an assessment of the potential impacts. For its part, Tepco has said there are no current plans to release the water. But the Associated Press (AP) reported that company officials are saying in private that they may have no choice.

According to Tanaka, Tritium is “so weak in its radioactivity it won’t penetrate plastic wrapping”. The substance can be harmful if ingested. According to AP, Tanaka had demonstrated the relatively tiny amount of tritium present in the combined Fukushima standing tanks – 57ml in total – by holding a small bottle half full of blue liquid in front of reporters.

A more useful measure of the amount of tritium is its radioactivity, which is measured in becquerels. According to the NRA, the tanks at Fukushima contain 3.4 peta becquerels (PBq) of tritium.

Despite the number of zeros in this measurement (there are 14), this is not a big number, said Ken Buesseler, a senior scientist at the Woods Hole Oceanographic Institution.

To put it in context, the natural global accumulation of tritium is a relatively tiny 2,200 PBq. The isotope has a half life of 12.3 years and is only created naturally on Earth by a rare reaction between cosmic rays and the atmosphere. By far the largest source of tritium in our environment is the nuclear weapons testing program of last century, which dumped a total of 186,000 PBq into the world’s oceans. Over time this has decayed to roughly 8,000 PBq. Another significant source of tritium are nuclear power stations, which have long dumped tritium-contaminated water into the ocean.

“I would think more has been put into the Irish Sea [from the UK’s Sellafield plant] than would ever be released off Japan,” said Buesseler. So far, the Fukushima disaster has seen 0.1-0.5 PBq leaked or released into the Pacific.

Even if all of the contaminated water were released into the ocean, it would not contain enough tritium to be detectable by the time it dispersed and reached the US west coast about four years later, said Simon Boxall, an oceanographer at the University of Southampton.

“In the broad scale of things, if they do end up putting the material in the Pacific, it will have minimal effect on an ocean basin scale,” said Boxall. “In an ideal world, we wouldn’t be in this situation. But the question is, what is the safest way forward? In many ways this is a pragmatic solution.”

But Boxall said there may be local effects – especially on the already heavily impacted fishing industry – as the contaminated water would take time to disperse.

International maritime law prohibits the building of a pipeline to send the waste offshore. Therefore any release would need to be slow. Tepco did not respond to questions regarding the environmental impact study called for by the IAEA.

Despite harbouring few prima facie fears about the 3.4PBq of tritium stored at Fukushima, Buesseler said the lack of transparency surrounding much of the post-tsunami decommissioning process made it impossible to be definitive about the safety of any course of action.

“Until you get the hard data, it’s hard to say if it’s a good idea or not. I want to have independent confirmation of what’s in every tank, which isotopes, how much they want to release per day. You get more of ‘don’t worry, trust us’,” said Buesseler

He notes that there have been minor differences between the official Tepco line that all leaks have stopped and Buesseler’s own measurements of very low levels of caesium and strontium still entering the ocean from the plant.

“It’s easy to have conspiracy theories when no-one is independently assessing what is going on,” he said.

The push for release will also be a blow to the hopes of US start-up Kurion, and their new parent company Veolia, which was awarded a $10m (£7m) grant from the Japanese government in 2014 to demonstrate that its tritium scrubbing technology could be scaled to meet the challenge of the Fukushima problem. The plan would create 90,000 tonnes of hydrogen gas, which Kurion said could be used to power vehicles.

Neither Tepco, nor Kurion, responded to requests for cost estimates of implementing this technology at the site. Kurion’s website calls it “cost-effective” and has said it could have its demonstration plant running within 18 months.

These costs are fundamental to the question of whether to release the material, because whatever they are, it is the price Japan seems unwilling to pay to fully clean up the lingering mess at Fukushima. ”

by Karl Mathiesen

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Here’s another perspective on the dumping of tritiated water in the Pacific by Inquisitr.

Arirang special: Fukushima and its aftermath (후쿠시마, 그 이후) — Arirang

This is an excellent video that explains concerns of radiation exposure in Japan and the safety standards for radiation in foods sold in Korea.

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How is Fukushima’s cleanup going five years after its meltdown? Not so well. — The Washington Post; Fukushima cleanup may take up to 40 years, plant’s operator says — CNN

Seen from the road below, the Fukushima Daiichi nuclear power station looks much as it may have right after the catastrophic earthquake and tsunami that caused a triple meltdown here almost five years ago.

The No. 3 reactor building, which exploded in a hydrogen fireball during the disaster, remains a tangle of broken concrete and twisted metal. A smashed crane sits exactly where it was on March 11, 2011. To the side of the reactor units, a building that once housed boilers stands open to the shore, its rusted, warped tanks exposed.

The scene is a testament to the chaos that was unleashed when the tsunami engulfed these buildings, triggering the world’s worst nuclear disaster since the one at Chernobyl, in Ukraine, in 1986. Almost 16,000 people were killed along Japan’s northeastern coast in the tsunami, and 160,000 more lost their homes and livelihoods.

Tokyo Electric Power Co. (Tepco), the utility company that runs the Fukushima plant and drew fierce criticism for its handling of the disaster, says the situation has improved greatly.

“In the last five years, radiation levels have been reduced substantially, and we can say that the plant is stable now,” said Akira Ono, the Tepco plant superintendent.

Efforts to contain the contamination have progressed, according to Tepco, including the completion Tuesday of a subterranean “ice wall” around the plant that, once operational, is meant to freeze the ground and stop leakage. Moves to decommission the plant — a process that could take 30 or 40 years, Ono estimated — are getting underway.

People will be allowed to return to their homes in the nearby town of Naraha next month and to Tomioka, even closer to the plant, next year. For now, Tomioka and neighboring Okuma remain ghost towns, lined with convenience stores, fast-food restaurants and gambling parlors that haven’t had a customer in five years. Bicycles lean near front doors, and flowerpots sit empty on windowsills.

A sign on the road to the plant showed a radiation reading of 3.37 microsieverts per hour, at the upper end of safe. At a viewing spot overlooking the reactor buildings, it shot past 200, a level at which prolonged exposure could be dangerous. Both readings are hundreds of times lower than they were a couple of years ago.

After about 20 minutes at the viewing spot, a Tepco official bustled visiting reporters, wearing protective suits, onto a bus. “We don’t want you out here too long,” he said. Below, men continued working on the site.

But one huge question remains: What is to be done with all the radioactive material?

There’s the groundwater that is flowing into the reactor buildings, where it becomes contaminated. It has been treated — Tepco says it can remove 62 nuclides from the water, including strontium, which can burrow into bones and irradiate tissue. It cannot filter out tritium, a radioactive isotope of hydrogen that can be used to make nuclear bombs but is not considered especially harmful to humans.

The water initially was stored in huge bolted tanks in the aftermath of the disaster, but the tanks have leaked highly contaminated radioactive water into the sea on an alarming number of occasions.

Now Tepco is building more-secure welded tanks to hold the water, theoretically for up to 20 years. There are now about 1,000 tanks holding 750,000 tons of contaminated water, with space for 100,000 tons more. The company says it hopes to increase capacity to 950,000 tons within a year or two, as well as halve the amount of water that needs to be stored from the current 300 tons per day.

As part of those efforts, Tepco built the 1,500-yard-long ice wall around the four reactor buildings to freeze the soil and keep groundwater from getting in and becoming radioactive. Company officials hoped to have the wall working next month; on Wednesday, however, Japan’s nuclear watchdog blocked the plan, saying the risk of leakage was still too high.

The options for getting rid of the contaminated water include trying to remove the tritium from it before letting it run into the sea; evaporating it, as was done at Three Mile Island, the Pennsylvania plant that melted down in 1979; and injecting it deep into the ground, using technology similar to that used to extract shale gas. A government task force is considering which option to choose. ”

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by Anna Fifield

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CNN:

” Tokyo (CNN) — Cleaning up Japan’s Fukushima Daiichi nuclear plant, which suffered catastrophic meltdowns after an earthquake and tsunami hit in 2011, may take up to 40 years.

The crippled nuclear reactor is now stable but the decommissioning process is making slow progress, says the plant’s operator Tokyo Electric Power Co, better known as TEPCO.

“If I may put this in terms of mountain climbing, we’ve just passed the first station on a mountain of 10 stations,” said Akira Ono, head of the Fukushima plant.

It’s almost five years since the earthquake and the tsunami it triggered killed more than 15,000 people and destroyed coastal towns on March 11, 2011.

TEPCO has attracted fierce criticism for its handling of the disaster.

Biggest challenge

The biggest obstacle to closing down the plant permanently is removing all the melted nuclear fuel debris from three reactors, Ono told reporters after a press tour of the plant this week.

But TEPCO says it is in the dark about the current state of the debris.

Hydrogen gas explosions and nuclear meltdowns released lethal levels of radiation in 2011.

Though radiation levels have fallen, they still prevent workers from accessing the reactor buildings, making it hard to survey the condition of the destroyed facilities and molten fuel debris.

What to do with the large volume of contaminated water now stored at the plant is another problem.

Around 300 to 400 tons of contaminated water is generated every day as groundwater flows into the plant filled with radioactive debris.

To contain the tainted water, TEPCO pumps up the water and stores it in tanks, adding a new tank every three to four days. There are 1,000 tanks today containing 750,000 tons of contaminated water.

However, decontamination elsewhere on the premises is making headway. Workers now only need dust masks for a large part of the plant.

For outsiders, this appears to be only small progress. But it makes a huge difference for workers who used to wear full masks for outside clean-up and construction work.

Last year in October, Japan confirmed the first case of cancer in a Fukushima worker.

While agreeing to cover the worker’s treatment costs, the government stopped short of recognizing the scientific link between the cancer and his work. “

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How Kurion plans to clean up Fukushima’s tritium nuclear waste — Bloomberg Business

” Innovator: Gaëtan Bonhomme
Age: 39
Chief technology officer at Kurion, a nuclear waste cleanup company with 200 employees that was acquired on Feb. 3 by Veolia, a French waste company

Form and function
Tritium is an especially tough nuclear waste to remove, because it’s a form of hydrogen and naturally bonds with water molecules. Kurion’s hardware separates contaminated water into component elements.

Background
In 2014, Kurion began removing strontium from 400,000 tons of contaminated water at Japan’s Fukushima nuclear power plant.

1. Separation
An electrolyzer splits the water’s oxygen molecules off from its contaminated hydrogen. The oxygen exits through one of the device’s tubes, while the hydrogen and tritium gas flows into a catalytic exchange column, where it’s combined with water.

2. Reduction
Kurion’s proprietary equipment keeps the hydrogen isolated in an ever smaller amount of water cycled through the exchange column. The net effect: 99 percent less contaminated water.

Revenue
Bonhomme says Kurion took in about $100 million last year selling cleanup equipment and services, like using chemicals and heat to turn toxic waste into glass.

Funding
Japan’s economic ministry has granted the company $8.3 million for research.

Next Steps
To show it can handle the tritium at Fukushima, Kurion brought a large-scale demo online at its Richland, Wash., office late last year. Kurion says it could begin processing Fukushima’s tritium-contaminated water in as little as 18 months, but that Japan’s government will likely take until 2018 to evaluate its technology. “We expect to be processing tritium-contaminated water in the U.S. before then,” says Bonhomme. ”

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Tepco completes sea wall to keep tainted Fukushima No. 1 water from reaching sea — The Japan Times

” Tokyo Electric Power Co. announced completion Monday of a 780-meter coastal wall along the heavily damaged reactor buildings of the Fukushima No. 1 nuclear power plant.

Tepco hopes the wall will significantly reduce the amount of contaminated water that has continued to flow into the Pacific more than four years after the 2011 meltdown crisis.

The gigantic wall, which the utility describes as impermeable, has an underground section that reaches as deep as 30 meters. It will reduce the amount of tainted water flowing into the sea from 400 tons to 10 tons a day, according to Tepco’s estimate.

Until Monday, about 400 tons of groundwater was draining along the sides of the buildings and into the sea each day, after being contaminated with fallout from the 2011 meltdown crisis, according to Tepco.

The utility says an estimated 150 tons of underground water is still flowing into the basements of the damaged reactor buildings each day.

The water, some of which has been circulated to cool melted nuclear fuel, is believed to be kept in place within the buildings by pressure exerted by higher underground water levels outside the buildings.

Last month, Tepco, after finally securing the consent of the local fishing industry, started draining underground water from around the plant buildings and dumping it into the sea after subjecting it to decontamination processes.

The launch of this draining operation put Tepco in a position to close the wall’s last 10-meter opening Monday.

The wall is now expected to reduce the amount of radioactive cesium and strontium entering the sea to one-fortieth of previous levels, and that of tritium to one-fifteenth of the previous levels, Tepco officials claimed.

Around 10 a.m., plant workers drove nine 30-meter steel pipes into the ground and injected mortar to fill the gaps between them, thereby closing the wall and mitigating the leakage of what Tepco calls “slightly tainted water” into the sea.

Recent tests of water samples from the nearby sea have detected radioactive substances such as cesium-137 and strontium-90, but scientists have said the density is so low that it poses no immediate danger to human health.

Yet, the ongoing flow of tainted water from the plant has raised anxiety and concerns among local fishermen and many consumers across the country.

Tepco plans to keep monitoring the density of radioactive materials in the nearby sea over the next month.

To isolate the four reactor buildings from the underground water, Tepco hopes to freeze the soil around them by the end of this year with coolant equipment already buried in the ground.

The Nuclear Regulation Authority has yet to give permission for the operation, saying creation of frozen soil could drastically change the underground water level around the plant.

If the water level outside falls lower than that inside, the contaminated water could leak out.

Meanwhile, Tepco has not explained exactly how it will control the water levels, an NRA official said. ”

source with video

Purification of contaminated water to be delayed by more than a year at Fukushima plant — Mainichi

” The planned completion of the purification of highly radioactive water stored at the Fukushima No. 1 Nuclear Power Plant is expected to be pushed back to sometime around May next year, more than a year later than initially planned, it has been learned.

Naohiro Masuda, chief decommissioning officer at the Fukushima Daiichi Decontamination & Decommissioning Engineering Co., disclosed the anticipated delay during an interview with the Mainichi Shimbun. The company was established by plant operator Tokyo Electric Power Co. to handle reactor decommissioning and contaminated water at the crippled plant.

While the purification process had initially been scheduled to be wrapped up by the end of this month, company officials gave up on achieving that goal in January following a series of malfunctions of the water purification system, called Advanced Liquid Processing System, or ALPS.

According to TEPCO, there is approximately 200,000 metric tons of contaminated water stored in tanks on the plant’s premises. In addition to the ALPS system that is capable of removing 62 types of radioactive materials including strontium, a newly installed apparatus that can single out strontium for removal is also in operation.

Masuda said during the interview that his company will prioritize the processing of strontium, which he says bears the largest influence, and aims to complete the process by the end of May.

Once strontium is got rid of, the concentration of radioactive materials in contaminated water would be trimmed to around one part per 1,000, he said. Because other types of radioactive substances will still remain in the contaminated water, purification of the entire amount of water is expected to finish around May next year, he said. ”

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