Tag Archives: zirconium cladding fires at spent fuel pools

The Enormous Task of Nuclear Waste Storage

“The Koeberg spent fuel pool storage capacity in South Africa  is currently over 90% full. (These) pools will reach (their) capacity by April 2020,” Eskom, the South African utility, told Reuters in a statement on Nov. 25, 2019.  Koeberg produces about 32 tonnes of spent fuel a year. Fuel assemblies, which contain radioactive materials including uranium and plutonium that can remain dangerous for thousands of years, are cooled for a decade under water in spent fuel pools.

Fuel Pool at Koeberg, South Africa

In 2016,  Eskom paid an estimated 200 million rand ($13.60 million) for an initial batch of seven reinforced dry storage casks from U.S. energy company Holtec International to help keep Koeberg running beyond 2018.  Eskom now has nine new unused casks on site, each with an individual capacity of 32 spent fuel assemblies, with another five expected to be delivered soon.

Holtec Cask

The 14 casks should ensure there is sufficient storage in the spent fuel pool until 2024, Eskom said, ahead of a tender for an extra 30 casks….Anti-nuclear lobby group Earthlife Africa said South Africa could not afford the social, environmental and economic costs associated with nuclear waste.  “We have a ticking bomb with high-level waste and fuel rods at Koeberg,” said Makoma Lekalakala, Earthlife Africa’s director.

Wendell Roelf, Waste storage at Africa’s only nuclear plant brimming, Reuters, Nov. 25, 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

Never-Ending CleanUp: Fukushima

 The operator of Japan’s wrecked Fukushima nuclear plant completed in April 2019 the removal of the first fuel rods from a cooling pool high up in a badly damaged reactor building, a rare success in the often fraught battle to control the site.  The batch of 22 unused fuel assemblies, which each contain 50-70 of the fuel rods, was transferred by a trailer to a safer storage pool, the last day of a four-day operation, Tokyo Electric Power Co, or Tepco, said in a statement.

The company must carefully pluck more than 1,500 brittle and potentially damaged assemblies from the unstable reactor No.4., the early stages of a decommissioning process following the 2011 earthquake and tsunami that wrecked the site.

Tepco estimates removing the damaged assemblies from reactor No.4 alone will take a year. Some experts say that timeline is ambitious.  Still, it is an urgent operation. They are being stored 18 meters (59 feet) above ground level in a building that has buckled and tilted and could collapse if another quake strikes.  Carefully plucking the damaged fuel assemblies from the reactor building is being seen as a test of Tepco’s ability to move ahead with decommissioning the whole facility – a task likely to cost tens of billions of dollars and take decades.  The removal has to be conducted under water. If the rods are exposed to air or if they break, huge amounts of radioactive gases could be released into the atmosphere. Each assembly weighs around 300 kg (660 pounds) and is 4.5 meters (15 feet) long.  The hazardous removal operation has been likened by Arnie Gundersen, a veteran U.S. nuclear engineer and director of Fairewinds Energy Education, to trying to pull cigarettes from a crushed pack

Exerpts from In Start of Long Operation, Fukushima Removes First Fuel Rods, Reuters, April 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