nuclear-news

The News That Matters about the Nuclear Industry Fukushima Chernobyl Mayak Three Mile Island Atomic Testing Radiation Isotope

Seven years on, radioactive water at Fukushima plant still flowing into ocean, study finds

Fukushima Daiichi still leaking radioactivity into Pacific Ocean. That expensive Ice wall turned out to be a slushy. Keep trying. Better yet, shut down before meltdown.

n-fukushima-a-20180330-870x559.jpg
Fukushima Daiichi still leaking radioactivity into Pacific Ocean. That expensive Ice wall turned out to be a slushy. Keep trying. Better yet, shut down before meltdown.
More than seven years after the March 2011 Fukushima nuclear crisis, radioactive water is continuing to flow into the Pacific Ocean from the crippled No. 1 plant at a rate of around 2 billion becquerels a day, a study has found.
The amount of leaking cesium 137 has decreased from some 30 billion becquerels in 2013, Michio Aoyama, a professor at the Institute of Environmental Radioactivity at Fukushima University, said in his study, which was presented Wednesday at an academic conference in Osaka.
The study said the concentration of radiation — 0.02 becquerel per liter of seawater found in samples collected near a coastal town 8 km south of the No. 1 plant — is at a level that does not affect the local fishing industry.
The radioactive water is generated in a process to cool melted nuclear fuel at three damaged reactors at the complex. The reactors experienced core meltdowns after the March 2011 earthquake and tsunami.
“It can be assumed that there is a path from the complex to the ocean” through which contaminated water flows, Aoyama said.
The water accumulates in the basements of the buildings at the site after being used to cool the melted fuel.
Tokyo Electric Power Company Holdings Inc., the operator of the Fukushima complex, has been trying to prevent contaminated water from increasing within the facilities by building an underground ice wall in an effort to block ground water. It has also built a seawall aimed at preventing contaminated water from entering the ocean.

April 7, 2018 Posted by | Fukushima 2018 | , , , | 2 Comments

Concern as leaky ‘ice wall’ around Fukushima nuke plant resembles ‘bamboo screen’

It has been nearly five and a half years since the meltdowns at Tokyo Electric Power Co. (TEPCO)’s Fukushima No. 1 nuclear plant, and both the utility and the Japanese government remain stymied in their efforts to control the buildup of radioactively contaminated water at the facility.

The problem is simply stated: Groundwater flows down from higher inland elevations towards the Pacific, collecting in the nuclear plant’s shattered reactor buildings and becoming contaminated. The plant grounds are packed with (occasionally leaky) storage tanks full of water pumped out of the reactor and turbine building basements, but the water does not stop.

TEPCO has attempted to stop the groundwater from getting into the buildings with a 1.5-kilomter subterranean “ice wall” (actually frozen soil) around the No. 1-No. 4 reactor buildings, but results have been inconclusive. Meanwhile, water decontaminated at the plant remains laced with radioactive tritium, and no storage site has yet been found to put this wastewater. The government is aiming to have all the radioactive water at the Fukushima plant dealt with by the end of 2020, the year Tokyo will host the Summer Olympics, but the way ahead is far from clear.

For one, the ice wall has holes in it.

“Due to heavy rain, the temperature rose above 0 degrees Celsius in two locations (along the wall),” a TEPCO public relations representative told a news conference on Sept. 1, the day after Typhoon Lionrock passed through northeastern Japan. The rainfall that came with the storm had caused a massive increase in the flow of groundwater, which then melted two holes in the ice wall, the official stated.

The freezing operation began in March this year, but part of the perimeter refused to solidify due to local geological features that caused the groundwater to flow particularly quickly. The fact that the typhoon’s rains could punch more holes in the wall revealed yet another weak point in the entire project, and experts have begun openly calling it a failure.

TEPCO decided on the ice wall in 2013, to close the spigot on the some 400 tons of radioactively contaminated water being produced daily at the Fukushima plant as groundwater came into contact with the melted fuel from the station’s reactor cores. A total of 1,568 pipes were sunk vertically 30 meters into the earth along a perimeter around the reactor buildings. Then coolant chilled to 30 degrees below zero was circulated through the pipes to freeze the surrounding soil and create an “ice dam.”

The project was treated as TEPCO’s trump card in its battle against the contaminated water problem, and the utility began the freezing operation along the plant’s seaward side in March this year. Freezing commenced on the rest of the wall in June, and TEPCO claimed that as of August, 99 percent of the seaward section and 91 percent of the landward section had been frozen successfully

However, in the five months since the operation began, there has been almost no drop in the amount of radioactive water produced. Experts at an Aug. 18 meeting of the Nuclear Regulation Authority (NRA) asked TEPCO point blank, “When will we see results?” Others commented, “TEPCO’s claim that the ice wall is highly effective at blocking the water flow is utterly bankrupt,” leaving utility officials fumbling for answers.

“The ice wall isn’t really a ‘wall’ per say, but more like a bamboo screen, which has gaps,” Nagoya University professor emeritus Akira Asaoka told the Mainichi Shimbun. “It’s obvious that the ice wall’s ability to block water is poor. A different type of wall should be considered as soon as possible.”

To complicate matters, the ice wall project is tangled up with expectations for the 2020 Tokyo Olympics. The Japanese government decided in September 2013 to commit large sums of public money to the ice wall and other contaminated water countermeasures. Four days later, Prime Minister Shinzo Abe was in Buenos Aires, telling the assembled members of the International Olympic Committee’s general session that “the situation (at the Fukushima plant) is under control.” He stated that the effects of the radioactive water had been entirely confined to the 0.3 square kilometers of the plant’s harbor. Later that day, Tokyo was announced as host of the 2020 Games.

So far, the central government has poured some 34.5 billion yen into the ice wall project. To say that the stupendously expensive initiative had failed would very likely invite scathing public criticism. Minister of Economy, Trade and Industry Hiroshige Seko told a news conference last month that “it’s true the ice wall is a difficult project, but the freezing is progressing.” And yet, no results have been forthcoming.

Solving the Fukushima No. 1 plant’s contaminated water problem by 2020 is inscribed in the reactor decommissioning schedule set by the government and TEPCO. If the ice is a failure, it would not just throw the work schedule off kilter; it would violate a publicly stated commitment to the international community.

To boost the ice wall’s effectiveness, in June TEPCO began injecting a specialized cement into parts of the perimeter that remained stubbornly unfrozen, and instituted supplementary projects to make the ground easier to freeze. TEPCO plans to freeze every side of the perimeter, but it remains to be seen if the utility will have anything to show for its work.

http://mainichi.jp/english/articles/20160907/p2a/00m/0na/011000c

September 7, 2016 Posted by | Fukushima 2016 | , , , | Leave a comment

Fukushima ice wall won’t stop all radioactive groundwater from seeping out – chief architect

5721f4ddc46188e14c8b45b7.jpg
An ice wall being built at the crippled Fukushima nuclear plant won’t completely prevent groundwater from flowing inside the facility and leaking out into the earth as radioactive water, according to a chief architect of the project.

Chief architect Yuichi Okamura told AP that gaps in the wall and rainfall will still allow for water to creep into the facility and reach the damaged nuclear reactors, which will in turn create as much as 50 tons of contaminated water each day.

“It’s not zero,” Okamura, a general manager at Tokyo Electric Power Co. (TEPCO) said. “It’s a vicious cycle, like a cat-and-mouse game…we have come up against many unexpected problems.”

The wall, which will be 1.5km (1 mile) long, will consist of an underground pipe network stretching 30 meters (100 feet) below the surface, around the reactor and turbine buildings. The pipes are designed to transport refrigerant cooled to -30° Celsius (-22°F) to chill the nearby soil until it freezes.

The barrier is being turned on in sections for tests, and the entire freezing process will take eight months since it was first switched on in late March. The process requires an amount of electricity that would power 13,000 Japanese households.

Despite its current efforts, TEPCO – the operator of the Fukushima plant – has been fiercely criticized by those who say the groundwater issue should have been forecasted and dealt with sooner.

Shigeaki Tsunoyama, an honorary professor and former president of University of Aizu in Fukushima, said that building a concrete wall built into the hill near the plant after the disaster would have minimized the contaminated water issue.

Okamura acknowledged that the option of building a barrier at a higher elevation near the plant was considered in the days following the disaster, but defended the actions of TEPCO, stressing that the priority is on preventing contaminated water from escaping into the Pacific Ocean.

Others have criticized the US$312 million wall, which is being built by construction company Kajima Corp., as a waste of taxpayer money.

TEPCO has repeatedly faced criticism for its handling of the Fukushima crisis, which occurred after a massive earthquake and subsequent tsunami led to a meltdown of reactors at the facility in March 2011. The disaster was the worst nuclear accident to take place since Chernobyl in 1986.

The company has admitted that it did not act properly during the disaster, confessing in February that it announced the nuclear meltdowns far too late. It also stated in a 2012 report that it downplayed safety risks caused by the incident, out of fear that additional measures would lead to a shutdown of the plant and further fuel public anxiety and anti-nuclear campaigns.

Despite the ongoing problems encountered following the meltdowns, TEPCO has set 2020 as the goal for ending the plant’s water problem – an aim which critics say is far too optimistic.

However, the water problem is just part of the monumental challenges faced at the facility. Controlling and dismantling the plant is expected to take 40 years. Robots have been tasked with taking photos of the debris, as the radiation levels are too high for humans to complete the job.

https://www.rt.com/news/341231-fukushima-ice-wall-groundwater/

April 28, 2016 Posted by | Fukushima 2016 | , , , | 1 Comment

Continuous Leaking Of Radioactive Strontium, Cesium From Fukushima To the Ocean

continuous-leaking-of-radioactive-strontium-cesium-from-fukushima-to-the-ocean-1024w.jpg

 

Scientists from the Universitat Autònoma de Barcelona (UAB) investigated the levels of radioactive strontium and cesium in the coast off Japan in September 2013. Radioactive levels in seawater were 10 to 100 times higher than before the nuclear accident, particularly near the facility, suggesting that water containing strontium and cesium isotopes was still leaking into the Pacific Ocean.

March 11 will be the 5th anniversary since the nuclear accident in Fukushima, Japan. The Tohoku earthquake and the series of tsunamis damaged the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) causing a massive release of radioactivity into the atmosphere and the Pacific Ocean. Since then, the Tokyo Electric Power Company (TEPCO) and the Japanese authorities have focused on controlling the water flowing in and out of the FDNPP and on decontaminating the highly radioactive water used as coolant for the damaged reactors (about 300 m3 a day, cubic meter = 1000 L). This cooling water is then stored in tanks and, to some extent, being decontaminated.

A new study recently published in Environmental Science and Technology, uses data on the concentrations of 90Sr and 134,137Cs in the coast off Japan from the moment of the accident until September 2013, and puts it into a longer-time perspective including published data and TEPCO’s monitoring data available until June 2015. This study continues the work initiated after the accident in 2011 by some of the authors. These and other partners from Belgium and Japan are currently involved in the European FRAME project lead by Dr. Pere Masqué that aims at studying the impact of recent releases from the Fukushima nuclear accident on the marine environment. FRAME is encompassed within the European COMET project (https://wiki.ceh.ac.uk/display/COM/COMET-FRAME).

Seawater collected from the sea surface down to 500 m between 1 and 110 km off the FDNPP showed concentrations up to 9, 124 and 54 Bq·m−3 for 90Sr, 137Cs and 134Cs, respectively. The highest concentrations, found within 6 km off the FDNPP, were approximately 9, 100 and 50 times higher, respectively, than pre-Fukushima levels. Before the accident, the main source of these radionuclides was atmospheric deposition due to nuclear bomb testing performed in the 1950s and 1960s. The presence of 134Cs (undetectable before the accident) and the distinct relationship between 90Sr and 137Cs in the samples suggested that FDNPP was leaking 90Sr at a rate of 2,3 — 8,5 GBq d-1 (giga-Becquerel per day) into the Pacific Ocean in September 2013. Such a leak would be 100-1000 times larger than the amount of 90Sr transported by rivers from land to ocean. Additional risk is related to the large amounts of water stored in tanks that have frequently leaked in the past. These results are in agreement with TEPCO’s monitoring data which show levels of 90Sr and 137Cs up to 10 and 1000 times higher than pre-Fukushima near the discharge channels of the FDNPP until June 2015 (most recent data included in the study). The presence of 90Sr and 134,137Cs in significant amounts until 2015 suggests the need of a continuous monitoring of artificial radionuclides in the Pacific Ocean.

https://organicslant.com/continuous-leaking-of-radioactive-strontium-cesium-from-fukushima-to-the-ocean/

March 20, 2016 Posted by | Fukushima 2016 | , , , , | Leave a comment