Tag Archives: radioactive pools

A Huge Headache: the Radioactive Water at Fukushima

What to do with the enormous amount of radioactive  water, which grows by around 150 tons a day at Fukushima, is a thorny question, with controversy surrounding a long-standing proposal to discharge it into the sea, after extensive decontamination.  The water comes from several different sources: Some is used for cooling at the plant, which suffered a meltdown after it was hit by a tsunami triggered by a massive earthquake in March 2011.  Groundwater that seeps into the plant daily, along with rainwater, add to the problem.

A thousand, towering tanks have now replaced many of the cherry trees that once dotted the plant’s ground. Each can hold 1,200 tons, and most of them are already full.  “We will build more on the site until the end of 2020, and we think all the tanks will be full by around the summer of 2022,” said Junichi Matsumoto, an official with the unit of plant operator TEPCO in charge of dismantling the site.

TEPCO has been struggling with the problem for years, taking various measures to limit the amount of groundwater entering the site.  There is also an extensive pumping and filtration system, that each day brings up tons of newly contaminated water and filters out as many of the radioactive elements as possible.

The hangar where the decontamination system runs is designated “Zone Y” — a danger zone requiring special protections.  All those entering must wear elaborate protection: a full body suit, three layers of socks, three layers of gloves, a double cap topped by a helmet, a vest with a pocket carrying a dosimeter, a full-face respirator mask and special shoes.  Most of the outfit has to burned after use.

“The machinery filters contain radionuclides, so you have to be very protected here, just like with the buildings where the reactors are,” explained TEPCO risk communicator Katsutoshi Oyama.  TEPCO has been filtering newly contaminated water for years, but much of it needs to go through the process again because early versions of the filtration process did not fully remove some dangerous radioactive elements, including strontium 90.

The current process is more effective, removing or reducing around 60 radionuclides to levels accepted by the International Atomic Energy Agency (IAEA) for water being discharged.  But there is one that remains, which cannot be removed with the current technology: tritium.

Tritium is naturally present in the environment, and has also been discharged in its artificial form into the environment by the nuclear industry around the world.  There is little evidence that it causes harm to humans except in very high concentrations and the IAEA argues that properly filtered Fukushima water could be diluted with seawater and then safely released into the ocean without causing environmental problems.

But those assurances are of little comfort to many in the region, particularly Fukushima’s fishing industry which, like local farmers, has suffered from the outside perception that food from the region is unsafe.

Karyn Nishimura, At Fukushima plant, a million-ton headache: radioactive water, Japan Times, Oct. 7, 2019
 

Anti-Nuclear Protests in India

Agitations against the Kudankulam nuclear plant broke out in June 2019.  Villages around the contentious reactors moved a resolution to put a stop to the government’s plans to construct an Away From Reactor (AFR) facility on the premises of the nuclear power plant.  The AFR is a storage unit meant to store spent fuel generated at the two nuclear plants in Kudankulam… While resolutions passed at four villages –  Kavalkinar, Vadakankulam, Perumanal  and Kudankulam  were recorded by district authorities, a similar move in the village of Vijayapathi was stopped. The decision led to protests in the village and was forcefully dispersed by the police. …

A public hearing regarding the AFR scheduled for July 10, 2019 was recently postponed indefinitely. A look at the circular shows that only two villages were invited – Kudankulam and Vijayapathi. Activists allege that this was an intentional attempt to shut down dissent against the proposed facility. 

The resolutions included – opposition to collection of nuclear waste in Kudankulam, demand to stop construction of an AFR facility and demand to permanently shut down the plant. Opposition parties and activists had urged the Centre to come out with a detailed plan for setting up a permanent deep geological repository and drop the plan of a proposed Away From Reactor facility.   “This entire exercise is meant to create storage for spent fuel and an AFR is only a temporary solution till the government finds land to build a deep geological repository,” explains Sundarrajan. “But across the country, no state is ready to risk giving land for permanent disposal of nuclear waste. So, residents fear that this will used as an excuse by the government to make the AFR a permanent storage space.”

Excerpts from Priyanka Thirumurthy , Protests break out in TN village over proposed facility in Kudankulam nuclear plant, the newsminute.com, June 29, 2019

How to Make Money out of the Nuclear Waste Mess

Companies specializing in the handling of radioactive material are buying retired U.S. nuclear reactors from utilities and promising to clean them up and demolish them in dramatically less time than usual — eight years instead of 60, in some cases.  Turning nuclear plants over to outside companies and decommissioning them on such a fast track represents a completely new approach in the United States, never before carried to completion in this country, and involves new technology as well…

Once a reactor is shut down, the radioactive mess must be cleaned up, spent nuclear fuel packed for long-term storage and the plant itself dismantled. The most common approach can last decades, with the plant placed in a long period of dormancy while radioactive elements slowly decay.  Spent fuel rods that can no longer sustain a nuclear reaction remain radioactive and still generate substantial heat. They are typically placed in pools of water to cool, staying there for at least five years, with 10 years the industry norm, according to the Nuclear Regulatory Commission. After that, they are removed and placed in giant cylindrical casks, typically made of steel and encased in concrete.

But Holtec International, which in the past year has been buying up several retired or soon-to-be-retired nuclear plants in the U.S., has designed a cask it says can accept spent fuel after only two years of cooling.  Holtec struck a deal last year to buy Oyster Creek in Forked River, New Jersey, from its owner, Exelon Generation.  It also has deals in place to buy several plants owned by Entergy Corp., including: Pilgrim, in historic Plymouth, Massachusetts, closing May 31; Palisades, in Covert, Michigan, set to shut down in 2022 ; and two reactors expected to close within two years at Indian Point in Buchanan, New York….  NorthStar Group Services, a specialist in nuclear demolition, completed the purchase of Vermont Yankee from Entergy with plans for its accelerated decommissioning.

The companies jumping into the business believe they can make in profit….Holtec will inherit the multibillion-dollar decommissioning trust funds set up by the utilities for the plants’ eventual retirement. , The company would be able to keep anything left over in each fund after the plant’s cleanup. By Holtec’s accounting, for instance, the Pilgrim decommissioning will cost an estimated $1.13 billion, leaving $3.6 million in the fund.  Holtec and Northstar are also banking on the prospect of recouping money from the federal government for storing spent fuel during and after the decommissioning, because there is no national disposal site for high-level nuclear waste…

Holtec has come under scrutiny over its role in a mishap in August 2018 during the somewhat less aggressive decommissioning of the San Onofre plant in Southern California, where two reactors were retired in 2013 and the estimated completion date is 2030….Holtec contractors were lowering a 45-ton spent fuel cask into an underground storage vault at San Onofre when it became misaligned and nearly plunged 18 feet, investigators said. No radiation was released.  Federal regulators fined Southern California Edison, the plant’s owner, $116,000, and an investigation found that some Holtec procedures had been inadequate or not properly followed.

BOB SALSBERG , Speedy reactor cleanups may carry both risks and rewards, Associated Press, May 21, 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