Tag Archives: radioactive pollution

Forever Fukushima: Cleaning Up the Huge Mess

By the end of 2019, Japan further delayed the removal of thousands of spent fuel units that remain in cooling pools since the 2011 disaster The government and the plant operator, Tokyo Electric Power Co., are keeping a 30- to 40-year completion target.

More than 4,700 units of fuel rods remain at the three melted reactors and two others that survived the 2011 earthquake and tsunami. They pose a high risk because their storage pools are uncovered and a loss of water in case of another major disaster could cause the fuel rods to melt, releasing massive radiation. Their removal at Units 1 and 2, after repeated delays, is now postponed by up to 10 years from the initial target of 2018, with more preparation needed to reduce radiation and clear debris and other risks.

Fuel rod removal at the Unit 1 reactor pool will begin sometime in 2027-2028, after debris is cleaned up and a huge rooftop cover installed to contain radioactive dust. Fuel removal at Unit 2 pool is to begin in 2024-2026. Work at the Unit 3 reactor pool began in April 2019 and all 566 units will be removed by March 2021. TEPCO has emptied the pool at Unit 4, which was offline and only suffered building damage, and aims to have all remaining rods in reactor pools removed by 2031 for safer storage in dry casks.

TEPCO has been unable to release the 1.2 million tons of treated but still radioactive water kept in nearly 1,000 tanks at the plant, fearing public repercussions and the impact on the area’s struggling fishing and agriculture. The amount of water is growing by 170 tons daily because it is used to cool the melted fuel inside the reactors.

The Ministry of Economy, Trade and Industry recently drafted a proposal to release the water to the sea or the air, or a combination of both. TEPCO says it can only store up to 1.37 million tons, or until the summer of 2022. Time is limited because preparation is needed before any water release. TEPCO and the government say the tanks pose risks if they were to spill their contents in another major earthquake, tsunami or flood…. The water is still somewhat contaminated, but TEPCO says further treatment can remove all but radioactive tritium to levels allowed for release. Experts say tritium is not harmful to humans in small amounts and has been routinely released from nuclear plants around the world.

Removing an estimated 880 tons of molten fuel from Fukushima’s three melted reactors is the toughest and unprecedented challenge. It’s six times the amount dealt with in the aftermath of the 1979 Three Mile Island partial core melt in the United States.  Removal is to begin in 2021 at Unit 2, where robotic probes have made more progress than at Units 1 and 3. A robotic arm was developed to enter the reactor from the side to reach the melted fuel, which has largely fallen to the bottom of the primary containment vessel… The first decade through 2031 is a crucial phase that will affect future progress…

Japan has yet to develop a plan to dispose of the highly radioactive melted fuel and other debris that come out of the reactors. TEPCO will compile a plan for those after the first decade of melted fuel removal. Managing the waste will require new technologies to reduce its volume and toxicity. TEPCO and the government say they plan to build a site to store waste and debris removed from the reactors, but finding one and obtaining public consent will be difficult.

Additionally, there will be an estimated 770,000 tons of solid radioactive waste by 2030, including contaminated debris and soil, sludge from water treatment, scrapped tanks and other waste. They will be sorted, treated and compacted for safe storage under a plan to be compiled by 2028.

The government says Fukushima’s decommissioning cost is estimated at 8 trillion yen ($73 billion), though adding compensation, decontamination of surrounding areas and medium-term storage facilities would bring the total to an estimated 22 trillion yen ($200 billion). The Japan Center for Economic Research, a think tank, estimates that decommissioning alone would cost 51 trillion yen ($470 billion) if the water is not released and tritium removal technology is pursued.

More than 10,000 workers will be needed annually in coming years, about one third assigned to work related to the radioactive water. 

Excerpts from MARI YAMAGUCHI,  Japan revises Fukushima cleanup plan, delays key steps, Associated Press, Dec. 27, 2019

Making Friends with Radioactive Waste: the Nuclear Dump of Moscow

Russian environmental activists and residents are sounding the alarm (in December 2019) over government plans to build a motorway near a Soviet-era radioactive waste site in southeast Moscow that they fear could spew dangerous particles into the air.  The 34-km (21-mile) road, which city authorities say is safe and will help ease traffic, is set to pass the Moscow Polymetal Plant and a fenced-off site where it disposed of radioactive substances decades ago.  Vasily Desyatkov, a senior city construction official, said surface and underground tests carried out where the foundations of the road were due to be laid had turned back normal readings that show there is no risk.

But that has not placated activists who have led a series of protests in recent months.  “It could lead to the release of radionuclides contained in the soil which will be dispersed with the dust. They will be spread everywhere – on people’s feet, car wheels, anything,” said Igor, a protester.

The site, the Moscow Polymetals Plant’s slag heap, is Just 13 kilometers from the Kremlin and steps from Kolomenskoye Park, a popular spot for Muscovites to ski in winter and picnic in summer, the Moskvorechye-Saburovo hill is the most contaminated of the bunch, according to Radon, a government agency tasked with locating and clearing radioactive waste. A legacy of a rushed Soviet effort to begin nuclear research as the race to build an atomic bomb gained steam in the 1930s, the hill is one of many contaminated sites across Russia …

Moskvorechye-Saburovo District Moscow

It contains tens of thousands of tons of radioactive waste left over after the extraction of thorium and uranium from ore. The factory ceased production of metals in 1996 for “environmental reasons,” according to its website — it now produces weapons and military equipment — and the dump is now a hill half a kilometer wide sloping down to the banks of the Moscow River.  City officials had been considering a full-scale clean-up for years, but never rubber-stamped a plan due to the risky location of the site near a source of water for Moscow’s southern suburbs. 

“Operations in such an environment are a serious engineering challenge — one incautious step, and radioactive soil gets into the river,” said Alexander Barinov, Radon’s chief engineer for Moscow…. “Full decontamination by removing all of the radioactive waste is simply impossible,” he added, noting that Radon every year conducts “a kind of therapy” to ensure the site’s safety — in short, dumping dirt on top of the waste to keep it buried after topsoil runoff each spring. 

Excerpts from Russians protest over plans to build road near Soviet-era radioactive waste site, Reuters, Dec. 10, 2019; Will a Road Through a Nuclear Dumping Ground Result in ‘Moscow’s Chernobyl’?, Moscow Times, July 16, 2019

Where to Go? 1 Million Tons Radioactive Water at Fukushima

In August 2019, Tepco projected that storage of radioactive water at the Fukushima nuclear plant would reach full capacity by around summer 2022 even after the expansion — the first time it has issued such a precise estimate.  According to Tepco, the Fukushima No. 1 plant had 960 massive tanks containing 1.15 million tons of treated water as of July 18, 2019. Water that has touched the highly radioactive melted fuel debris has been cleaned up through water treatment machines and is stored in the tanks, but the high-tech treatment machines are able to remove most radionuclides except tritium. The plant currently sees an increase of contaminated water by 170 tons a day, Tepco says.

Releasing tritium-tainted water into the sea in a controlled manner is common practice at nuclear power plants around the world, and it was generally considered the most viable option as it could be done quickly and would cost the least.  The head of the Nuclear Regulation Authority, Toyoshi Fuketa, has long said that releasing the treated water into the sea is the most reasonable option, but people in Fukushima, especially fishermen, fear it will damage the region’s reputation.

Addressing those concerns, the government panel, launched in November 2016, has been looking for the best option in terms of guarding against reputational damage. Injecting it into the ground, discharging it as steam or hydrogen, or solidification followed by underground burial have all been on the table. Under the current plan, Tepco is set to increase the tank space to store 1.37 million tons of water a total, but estimates show that will only last until summer 2022.  But the more space it creates, the bigger the decommissioning headache becomes.

Excerpts from KAZUAKI NAGAT, Fukushima nuclear plant to run out of tanks to store tritium-laced water in three years, Tepco says, Japan Times, Aug. 9, 2019
BY KAZUAKI NAGATA

How Nuclear Explosions Affect the Deep Ocean

Radioactive carbon released into the atmosphere from 20th-century nuclear bomb tests has reached the deepest parts of the ocean, new research finds.  A new study in AGU’s journal Geophysical Research Letters finds the first evidence of radioactive carbon from nuclear bomb tests in muscle tissues of crustaceans that inhabit Earth’s ocean trenches, including the Mariana Trench, home to the deepest spot in the ocean.

Mariana Deep Ocean Trench

Organisms at the ocean surface have incorporated this “bomb carbon” into the molecules that make up their bodies since the late 1950s. Crustaceans in deep ocean trenches are feeding on organic matter from these organisms when it falls to the ocean floor. The results show human pollution can quickly enter the food web and make its way to the deep ocean, according to the study’s authors.



Crustacean

According to researchers, water containing carbon-14 can take centuries to circulate throughout the ocean, but the food web drastically accelerated the process. “There’s a very strong interaction between the surface and the bottom, in terms of biologic systems, and human activities can affect the biosystems even down to 11,000 meters,” said Weidong Sun, a coauthor of the study, “so we need to be careful about our future behaviors.”

RADIOACTIVE CARBON FROM NUCLEAR BOMB TESTS FOUND IN DEEP OCEAN TRENCHES
AGU Press Release, 8 May 2019

Institutions Go Way But Not Nuclear Waste

The Trump administration  is asking Congress for money to resume work on the Yucca Mountain nulcear waste storage in Nevada.  But that may not end local opposition or a longstanding political stalemate. And in the meantime, nuclear plants are running out of room to store spent fuel….As the waste piles up, private companies are stepping in with their own solutions for the nation’s radioactive spent fuel. One is proposing a temporary storage site in New Mexico, and another is seeking a license for a site in Texas.

Most experts agree that what’s needed is a permanent site, like Yucca Mountain, that doesn’t require humans to manage it.  “Institutions go away,” says Edwin Lyman, acting director of the Nuclear Safety Project at the Union of Concerned Scientists. “There’s no guarantee the owner will still be around for the duration of time when that waste remains dangerous, which is tens or hundreds of thousands of years.”

A California company says it has a viable plan for permanent storage. Deep Isolation wants to store spent fuel in holes drilled at least 1,000 feet underground in stable rock formations. The company says the waste would be separate from groundwater and in a place where it can’t hurt people.  “I like to imagine having a playground at the top of the Deep Isolation bore hole where my kids and I can go play,” says CEO Elizabeth Muller.  In November 2018, Muller’s company conducted a test north of Austin, Texas. Crews lowered an 80-pound canister into a drilled hole. It was a simulation, so no radioactive substances were involved. The goal was to determine whether they could also retrieve the canister.  The test was successful, and that’s important. Regulators require retrieval, because new technology could develop to better deal with the spent fuel. And the public is less likely to accept disposal programs that can’t be reversed, according to the International Atomic Energy Agency.

Proving the waste can be retrieved may be the easy part. The bigger challenge is federal law, which doesn’t allow private companies to permanently store nuclear waste from power plants.  Current law also says all the waste should end up at Yucca Mountain in Nevada. By contrast, Deep Isolation’s technology would store waste at sites around the country, likely near existing nuclear power plants.

Jeff Brady, As Nuclear Waste Piles Up, Private Companies Pitch New Ways To Store It, NPR, Apr. 30, 2019

Devil’s Idea for Tokyo’s End: Fukushima

By late March 2011… after tsunami struck the Fukushima Daiichi plant—it was far from obvious that the accident was under control and the worst was over. Chief Cabinet Secretary Yukio Edano feared that radioactive material releases from the Fukushima Daiichi plant and its sister plant (Fukushima Daini) located some 12 km south could threaten the entire population of eastern Japan: “That was the devil’s scenario that was on my mind. Common sense dictated that, if that came to pass, then it was the end of Tokyo.”

Prime Minister Naoto Kan asked Dr. Shunsuke Kondo, then-chairman of the Japanese Atomic Energy Commission, to prepare a report on worst-case scenarios from the accidenta .  Dr. Kondo led a 3-day study involving other Japanese experts and submitted his report (Kondo, 2011) to the prime minister on March 25, 2011. The existence of the report was initially kept secret because of the frightening nature of the scenarios it described. An article in the Japan Times quoted a senior government official as saying, “The content [of the report] was so shocking that we decided to treat it as if it didn’t exist.” …

One of the scenarios involved a self-sustaining zirconium cladding fire in the Unit 4 spent fuel pool. Radioactive material releases from the fire were estimated to cause extensive contamination of a 50- to 70-km region around the Fukushima Daiichi plant with hotspots significant enough to require evacuations up to 110 km from the plant. Voluntary evacuations were envisioned out to 200 km because of elevated dose levels. If release from other spent fuel pools occurred, then contamination could extend as far as Tokyo,…There was particular concern that the zirconium cladding fire could produce enough heat to melt the stored fuel, allowing it to flow to the bottom of the pool, melt through the pool liner and concrete bottom, and flow into the reactor building.

Lessons Learned from the Fukushima Daiichi Accident for Spent Fuel Storage: The U.S. nuclear industry and its regulator should give additional attention to improving the ability of plant operators to measure real-time conditions in spent fuel pools and maintain adequate cooling of stored spent fuel during severe accidents and terrorist attacks. These improvements should include hardened and redundant physical surveillance systems (e.g., cameras), radiation monitors, pool temperature monitors, pool water-level monitors, and means to deliver pool makeup water or sprays even when physical access to the pools is limited by facility damage or high radiation levels….

[At nuclear power plants there must be…adequate separation of plant safety and  security systems so that security systems can continue to function independently if safety systems are damaged. In particular, security systems need to have independent, redundant, and protected power sources…]

Excerpts from Lessons Learned from the Fukushima Accident for Improving
Safety and Security of U.S. Nuclear Plants: Phase 2, US National Academies, 2016

Crabs in Radioactive Seas: Kara Sea

The Soviet Union during the 1960s and 70s dumped several hundred containers with solid radioactive waste in the Blagopoluchie Bay in Novaya Zemlya. Back then, these waters were covered with ice overwhelming parts of the year.  Today, that is quickly changing. The bay located in the northern part of the Russian Arctic archipelago is now ice-free increasing parts of the year. With the retreating ice follow new species.

Researchers from the Russian Shirshov Institute of Oceanology have comprehensively studied the eco system of the bay for several years. Among their key findings is a quickly growing number of snow crabs. In this year’s research expedition to the remote waters, the researchers were overwhelmed by the numbers. According to the institute, the crab invasion can be described «as avalanche».

The number of crabs in the area is now estimated to almost 14,000 per hectare, the institute informs. With the help of underwater photo and video footage, the researchers have studied how the crab expansion is leading to a other reduction in other marine life on the sea bottom.    A further spread in the other parts of the Kara Sea is imminent, and the Russian Fisheries Agency (Rosrybolovstvo) believe that the Kara Sea will ultimately become an area with commercial crab fishing.

But Kara seas is a major nuclear waste dump…No major leakage from the radioactive materials have so far been registered.  Soviet authorities are believed to have dumped about 17,000 containers with solid radioactive wastes in Arctic waters and primarily in the Kara Sea. More than 900 containers are located on the bottom of the Blagopoluchie Bay. Also a number of reactor compartments were dumped, as well as three nuclear subs and other nuclear materials.

Exceprts from Atle Staalesen, Arctic crab invasion comes to nuclear waste graveyard, the Barents Observer, Nov. 26, 2018