When it planned the Callaway nuclear plant in the mid-1970s, Union Electric Co. had a straightforward, if wishful, strategy for managing the still-radioactive used fuel: Cool it in water for a few years, then haul it away for reprocessing or permanent storage.
But the permanent solution never materialized, as the federal government failed on its promise to build a geologic repository. Almost 27 years later, the tens of thousands of uranium-filled fuel rods removed from Callaway's reactor core are still steeping in the same 40-foot-deep stainless steel-lined pool - their final destination unknown.
St. Louis-based Ameren Corp., the successor to Union Electric, has managed Callaway's waste by increasing the density of spent fuel in the tennis-court-sized pool. But it will run out of room in 2019. The deadline has the utility developing plans to entomb some of the oldest used fuel in steel and concrete casks - creating a sort of nuclear graveyard.
The storage question - one with white-hot political implications - vexes nuclear operators nationwide and complicates efforts to expand nuclear capacity, even as many tout it as a cleaner alternative to coal. Spent fuel pools continue to fill, prompting industry watchdogs to urge an accelerated transfer of fuel from pools to so-called dry casks, which they argue are much safer.
In recent weeks, panels of experts have urged establishment of interim storage sites.
But neither proposed solution is permanent, leaving unanswered the question that looms over the industry: Where will the U.S. store the almost 65,000 metric tons of high-level nuclear waste piling up at reactors in 33 states? That's enough to fill a football field 21 feet deep.
This issue sparked debate a decade ago, after the Sept. 11 attacks raised fear of terrorism at nuclear plants, but public awareness soon faded. In March, the powerful earthquake and tsunami that triggered a crisis at Japan's Fukushima Daiichi nuclear complex and radiation leaks from two of its spent fuel pools again brought questions to the forefront.
"This problem is no longer an abstract issue, especially if you look at the visual evidence of what has happened at Fukushima Daiichi in recent months," said Robert Alvarez, a senior scholar at the Institute for Policy Studies, a liberal think tank based in Washington.
Alvarez, a former Department of Energy policy adviser to President Bill Clinton, has led a push to change spent fuel storage. He authored a 2003 report that outlined the danger posed by the pools as targets of terrorist attacks. His new study published this month makes many of the same points.
The paper eight years ago drew a sharp response from federal regulators and the nuclear industry - even though the National Academies of Science agreed with some of his findings. The NRC and nuclear operators insisted then, as now, that spent fuel storage practices are safe.
Meanwhile, efforts to find a lasting solution founder. The federal government spent two decades and $15 billion studying a possible repository for high-level nuclear waste at Yucca Mountain, on federally owned land in the Nevada desert, which was supposed to begin accepting waste in 1998. The government pushed the opening date to 2017, then 2020, before President Barack Obama deep-sixed the project last year.
The action infuriated many in the nuclear industry and in Congress, including Rep. John Shimkus, R-Collinsville. As chairman of the Subcommittee on Environment and the Economy, the Illinois congressman toured the Yucca site a few weeks ago with two colleagues who are pushing to revive efforts to construct a geologic repository there.
"If you can't put high-level nuclear waste there, you can't put it anywhere," Shimkus said in an interview. "It's the most studied location on the planet."
Money for nothing
As nuclear operators generate power and nuclear waste, consumers pay the federal government for a permanent disposal solution that doesn't exist.
A 30-year-old federal law requires Ameren and other utilities to charge a tenth of a cent per kilowatt-hour for energy generated at nuclear plants to pay for long-term waste disposal. Ameren customers have paid $214.6 million into the fund, and the meter is still running.
The core of Callaway's reactor holds 193 fuel assemblies - bundles of 12-foot-long zirconium alloy rods, each of which contains hundreds of thumbnail-size ceramic pellets of uranium dioxide.
Every 18 months, the reactor is shut down for about a month to "refuel." About 40 percent of these fuel assemblies are replaced, with the older ones moved into the spent fuel pool. The water cools the rods and shields plant workers from radiation. A single fuel rod is so hot and radioactive at the time it's removed from the reactor core that exposure at a distance of one foot would be lethal in seconds.
An initial design for Callaway by designer Westinghouse in 1974 called for the spent fuel pool to accommodate 350 fuel assemblies. By the time the plant was complete a decade later, the pool was licensed for 1,344 assemblies. In 1999, Ameren got approval to rearrange the pool, a widely used practice called "re-racking," to double the licensed capacity to more than 2,642 fuel assemblies.
At the time, a repository at Yucca Mountain was still in the works.
Today at Callaway, the spent pool holds 1,568 irradiated fuel assemblies. That collectively represents about 700 metric tons of high-level radioactive waste and 141 million curies of radioactivity, according to an estimate in Alvarez's report. (A curie is a unit of measurement for radioactivity.)
Chief Nuclear Officer Adam Heflin said Ameren considered re-racking the pool again to accommodate more spent fuel but determined it wouldn't be worthwhile, especially after the Yucca Mountain project was scuttled. Instead, Ameren started developing plans to move some spent fuel to casks.
Heflin said some of the oldest spent fuel would be moved into dry casks beginning in 2016, perhaps a year earlier if new regulations are enacted in response to the Fukushima disaster. In general, the casks are large concrete and steel tombs licensed to hold spent nuclear fuel for at least 60 years. They're considered by some a safer alternative because they don't require water, pumps or electricity to provide cooling. Instead they're filled with nitrogen, helium or another inert gas and cool by natural convection.
THE COST OF SAFETY
At Japan's Fukushima reactors, the loss of electricity caused water in at least one spent fuel pool to boil off enough to expose radioactive material, triggering a hydrogen explosion and spent fuel fire.
Another pool was significantly damaged by a hydrogen explosion from the venting of the reactor vessel. Lead-shielded helicopters dropped water from above while water canons on firetrucks sprayed from below - all in an effort to prevent further damage. Still, the pool remains near boiling and is emitting high doses of radiation.
Meanwhile, used fuel that had been sealed in casks at Fukushima stayed intact, unaffected.
However minuscule the chance of such an accident in the U.S., watchdogs have pressed regulators to move spent fuel to casks as soon as possible. David Lochbaum, a licensed nuclear engineer and head nuclear safety program at the Union of Concerned Scientists, has long called on regulators and Congress to mandate dry cask storage - a step Germany took 25 years ago.
But three-fourths of all spent fuel in the U.S. remains submerged. Reducing the amount of fuel in pools would generate a lower heat load, buying workers extra time to avoid overheating if cooling systems failed, Lochbaum said during testimony before Congress this month.
The only reason the nuclear industry resists doing so is cost, critics say. "This is an example of foot-dragging in order to save money on the part of the reactor operators," Alvarez said.
Ameren hasn't publicly disclosed estimated costs of converting to dry storage, but other nuclear operators have cited cask costs up to $1.5 million apiece. A recent Government Accountability Office study reported that costs of converting a single reactor would be $30 million to $60 million. And the Electric Power Research Institute last fall estimated the cost at $3.6 billion for all U.S. plants.
Critics paint a grim picture of what could happen if a pool packed with spent nuclear fuel loses cooling in a natural disaster or terrorist attack. Spent nuclear fuel could heat up to the point that the zirconium cladding catches fire, releasing radioactivity. The biggest threat comes from cesium 137 - the radioactive isotope that during the Soviet Union's 1986 Chernobyl disaster rendered an area half the size of New Jersey uninhabitable. That disaster involved the release of 2 million to 3 million curies of cesium; the spent fuel pools at some U.S. reactors contain several times more than that.
"We have to stop deluding ourselves into thinking that jamming as much spent fuel into pools is a wise idea," Alvarez said.
'ROCK AND A HARD PLACE'
Utility executives, regulators and other experts defend spent fuel pools as safe. Obama's Blue Ribbon Commission agreed in its preliminary recommendations for spent fuel management issued this month.
Andy Kadak, a consultant and former nuclear engineering professor at the Massachusetts Institute of Technology, said during a press conference last month that he doesn't think transfer of spent fuel to casks would improve safety at plants. The pools would still be needed under any scenario, because the fuel must be stored in water for five years before it cools to the point where it can be moved to dry casks. So pools would still hold the hottest, most radioactive fuel.
"We can transfer all of the other stuff out of the pools," Kadak said. "But it doesn't necessarily or significantly reduce the risk associated with the problems at Fukushima."
Nuclear operators in Missouri and Illinois agree. Scott Bond, Ameren Missouri's manager of nuclear development, said the fuel building at Callaway was designed to take a direct hit from an EF5 tornado - a twister as powerful as the one that wrought so much destruction in Joplin last week.
"It is a fortress," Bond said.
By contrast, nuclear industry critics say, some reactor pools' are protected by thin metal roofs that have been described as little sturdier than a backyard storage shed.
Like Ameren, Exelon Corp. - with 10 plants and 17 reactors in Illinois and two other states - believes that used fuel can be safely stored in either the pools or dry casks, spokeswoman Krista Lopykinski said. The Chicago-based company, the nation's largest nuclear operator, said the acceleration of dry cask storage doesn't significantly reduce the used fuel pool heat load, which is largely determined by the most recent fuel discharged from the reactor.
The report from the Electric Power Research Institute said cost isn't the only consideration. The additional fuel handling involved with moving spent fuel to dry casks after five years would increase radiological exposure to nuclear workers. It would tax manufacturing and fabrication capabilities and increase risks associated with cask handling and require increased NRC inspection and oversight of cask designers, fabricators and dry storage loading operations.
"We're kind of stuck between a rock and a hard place," Bond said.
WASTED TIME, MONEY
Whatever twists the spent fuel debate takes, it ultimately leads back to the inescapable reality that the U.S. lacks a permanent repository for used nuclear fuel. And building one will take decades.
The question has vexed the federal government since a 1957 National Academies of Science report suggested a geologic repository was the safest, most secure method of isolating high-level nuclear waste.
The other option, favored by nuclear industry, is to reprocess or recycle the used fuel to take advantage of still-untapped energy. Reprocessing is the standard in countries including France, Great Britain and Japan, but it is widely opposed by environmentalists here and seemingly less likely following the Fukushima disaster. Even if reprocessing were allowed, it wouldn't change the fact that the country still needs a permanent repository for high-level waste residues.
The 1982 Nuclear Waste Policy Act charged the U.S. Department of Energy to build and operate an underground disposal facility called a geologic repository. Since the late 1970s - and exclusively for the past two decades - the search for a long-term storage for a nuclear waste repository has focused on Yucca Mountain. Then that effort crumbled amid legal challenges, concerns over how to transport nuclear waste to the facility and political pressures.
The project has faced stiff opposition from environmentalists and Nevada politicians ever since being proposed. U.S. Sen. Harry Reid, D-Nev., declared it "dead" after becoming Senate Majority Leader.
Meanwhile, utility customers across the country continue to pay into the fund created by the 1982 act. In addition to the money apparently squandered on studying Yucca, the GAO report said taxpayers have paid almost $1 billion as a result of 74 industry lawsuits where courts have ordered the government to compensate utilities for its failure to store spent fuel as mandated. And the Justice Department has spent an additional $168 million defending the Energy Department in these lawsuits.
Exelon is among the companies that have settled with the Energy Department. The deal allows for reimbursement of costs for dry storage up to the amount of fuel that would have been handled by the government since 1998 - the original target date for opening Yucca Mountain - until the department finds a permanent site to store waste. Ameren filed a lawsuit against the Energy Department in 2004. The suit had been suspended, but the parties are now in discussions, Bond said.
Meanwhile, a group of electric utilities and the Nuclear Energy Institute have sued the Department of Energy seeking to halt payments into the fund. The lawsuit is pending.
Obama's Blue Ribbon Commission is due to issue its final recommendations next year. Whatever it recommends, experts agree that establishing a permanent geologic repository is still likely decades away. Even an interim storage site could take up to 33 years to plan and implement, according to the GAO report.
Meanwhile, Shimkus pledges to continue pushing to get Yucca back on track.
"I want high-level nuclear waste, as much as possible, to be in a central location," he said, "not 104 locations."