Archival photo of the Shippingport Atomic Power StationLibrary of Congress / Reuters

It was just another day in the life of the defunct Hanford nuclear site, a remote part of Washington State that made most of the plutonium in America’s Cold War arsenal. On the morning of May 9, 2017, alarms sounded. Around 2,000 site workers were told to take cover indoors, and aircraft were banned from flying over the site for several hours. The roof of a tunnel had collapsed, exposing railcars that had been loaded with radioactive waste from plutonium production and then shunted underground and sealed in decades before.

This post is adapted from Pearce’s new book.

There was other stuff down there too. Nobody quite knew what. Record keeping was poor, but the contents of the tunnels certainly included carcasses from animal radiation experiments, including a reported 18 alligators. The emergency lasted only a few hours. The integrity of the waste was restored. But it was a chilling reminder of the site’s perilous radioactive legacy.

Sprawling across 600 square miles of sagebrush semidesert, Hanford is a $100 billion cleanup burden, full of accidents waiting to happen. It is the biggest headache, but very far from being the only one, emerging in what increasingly look like the final years of America’s nuclear age.

It is 60 years since America’s first commercial nuclear power station was opened by President Dwight D. Eisenhower at Shippingport, near Pittsburgh, Pennsylvania, on May 26, 1958. But the hopes of a nuclear future with power “too cheap to meter” are now all but over. All that is left is the trillion-dollar cleanup.

Public fear and suspicion about all things nuclear grew sharply after March 1979, when the cooling system at Three Mile Island Nuclear Generating Station failed and triggered a meltdown. In the end, actual releases of radiation were minimal, but the incident left behind a reputational mess in addition to the radiological one. On the day of the accident, the United States had 140 operating nuclear reactors, with 92 under construction and 28 more awaiting official approval. In the next five years, more than 50 orders for new nuclear reactors in America were canceled. New contracts entirely dried up.

Hanford has not produced plutonium for three decades. Nobody is making new material for bombs anymore. President Trump’s plans for more weapons can be met by recycling existing plutonium stocks. And even the civil nuclear industry, which still generates a fifth of America’s electricity, is in what looks like terminal decline. With cheap natural gas and renewable solar and wind energy increasingly available, the numbers no longer add up. Nuclear power plants across the nation are being closed with years of licensed operation unused.

No new nuclear power stations have come on line in the past two decades. The only new build underway, two additional reactors at Georgia Power’s Alvin W. Vogtle plant near Waynesboro, is five years behind schedule and has seen its costs double. Its planned completion in 2022 remains uncertain.

America’s 99 remaining operational nuclear power reactors, which still deliver power to the grid, are too important to be closed overnight. But nearly half are over 40 years old. The only question is how long the regulators and accountants will allow them to keep going.

Oyster Creek in New Jersey disconnects from the grid in October with 11 years left on its license. Indian Point in New York State is to shut by 2021 due to falling revenues and rising costs. In California, Diablo Canyon is being closed by state regulators in 2025. The reactor at Three Mile Island in Pennsylvania that survived the 1979 accident will finally shut in 2019.

Shutdown is only the beginning of the end. Final closure and clearance of the sites can take decades, and the waste crisis created by decommissioning cannot be dodged. Lethal radioactive material is accumulating at dozens of power plants, military facilities, and interim stores across the country.

Some, like the train cars buried at Hanford, is evidently in a precarious situation. Much more needs urgent attention. Cleaning up and safely disposing of the residues of the nuclear adventure—much of it waste with a half-life measured in tens of thousands of years—is turning into a trillion-dollar nightmare for the nation.

Rocky Flats Wildlife Refuge is an oasis of prairie biodiversity covering 5,000 acres, home to prairie dogs, elk, monarch butterflies, and rare xeric grasses. It also serves as a buffer zone around the site of the largest completed nuclear cleanup to date in the United States. And David Lucas of the U.S. Fish and Wildlife Service is preparing to open it for public access in summer 2018. He’s reckoning on 150,000 visitors a year.

During the Cold War, Rocky Flats was secretly machining plutonium manufactured at Hanford into some 70,000 spheres that formed the explosive heart of each weapon in Uncle Sam’s nuclear arsenal. Plutonium pollution was routine. The plant had nowhere to get rid of the day-to-day plutonium waste, which was often dumped in hastily dug landfills or sprayed onto grassland around the plant. At an outdoor compound known as pad 903, where more than 5,000 drums of waste liquids contaminated with plutonium are stored, there’s been substantial leakage. An internal memo reported that rabbits living on the site were heavily contaminated, especially in their hind feet.

A whistle-blower’s allegations about illegal late-night incineration of plutonium waste at the plant led to an FBI raid in 1989. After that—and with demand for plutonium spheres declining following the end of the Cold War—the government closed the site. A federal grand jury sat for three years to hear testimony from the FBI raid. But two days after the jury approved indictments, the Justice Department struck a deal with Rockwell Automation, the company that managed the plant. The company pleaded guilty to some minor charges, but the FBI evidence and grand jury conclusions were sealed forever.

After the cover-up came the cleanup. The core plutonium-handling areas were declared a Superfund site, qualifying for a federal decontamination, which was completed in 2005. The federal government called it “the largest and most successful environmental cleanup in history.” But in reality it was a cut-price job. The original project was estimated at $37 billion, but Congress would sanction only $7 billion. So processing buildings were demolished, but basements and 25 miles of underground tunnels and pipelines were left behind, according to LeRoy Moore, a veteran activist who sat on a public committee in the 1980s that considered the cleanup plans.

Today, the land that housed the industrial complex remains behind a sturdy fence under the control of the Department of Energy (DOE). But the large grassland buffer zone that once protected the complex from prying eyes has been released into the care of the Fish and Wildlife Service for public access.

There are two concerns. First that, as I saw on a tour with Lucas, the fenced-off core area hardly looks self-contained. Earth slips have left ugly gashes up to 300 feet wide across a former landfill site that overlooks a creek running through the wildlife refuge. The DOE’s Scott Surovchak concedes that “slumping is very common” after heavy rain. Only constant repairs, it seems, will prevent the landfills and buried contaminated buildings and pipework from being exposed.

The second concern is the safety of the buffer zone itself. Harvey Nichols, a biologist from the University of Colorado, has found that when the plant was operating snow falling nearby was often “hot.” Falling snowflakes captured tiny plutonium particles that evaded the stack filter. Just two days of snowfall could deposit about 14 million particles on every acre of the site. “There must be tens of billions of particles in the soil today,” he told me.

The Environmental Protection Agency has dismissed such concerns. In 2006 it found plutonium levels in soil samples in the buffer zone were within acceptable limits and concluded that the lands comprising the refuge are “suitable for unlimited use and unrestricted exposure.” But Moore, the activist, is unimpressed. “Prairie dogs and other critters will burrow down for several feet and bring plutonium to the surface,” he says. “Children will be exposed to plutonium. And people will start taking plutonium out into their communities on boots and cycle wheels. Why would we allow that?”

Lucas is unmoved. “We need to get people out here on the refuge. Then the fears will evaporate,” he told me. But that is just what worries his opponents. Forgetting about the plutonium is the worst thing that could happen, they say.

About 30 miles northeast of Rocky Flats, out on the prairie near the small town of Platteville, is the Fort St. Vrain spent-fuel store. It resembles nothing so much as an outsize grain store, but since the 1990s it has been holding 1,400 spent fuel rods, laced with plutonium and encased in blocks of graphite. The spent fuel was left behind when the neighboring nuclear power plant shut. The plan had been to send it to another temporary store at the Idaho National Laboratory, but the governor of Idaho banned the shipment. The Fort St. Vrain facility is designed to withstand earthquakes, tornado winds of up to 360 miles per hour, and flooding six feet deep. Also time. It will be several decades at least before the federal government finds the fuel a final resting place.

The country is littered with such caches of spent fuel stuck in limbo. According to the Government Accountability Office (GAO), 80,000 metric tons of spent fuel, the most dangerous of all nuclear wastes, is stored at 80 sites in 35 states. The sites include stores at past and present power plants such as Maine Yankee, and stand-alone federal sites such as Fort St. Vrain. As the GAO puts it: “After spending decades and billions of dollars ... the future prospects for permanent disposal remain unclear.” Nobody wants to give the stuff a forever home.

Nuclear waste is conventionally categorized as high-, intermediate-, or low-level. Low-level waste includes everything from discarded protective clothing to plant equipment and lab waste. It can usually be treated like any other hazardous waste, which in practice usually means burial in drums in landfills or concrete-lined trenches.

Intermediate waste contains radioactive materials with isotopes that decay with half-lives long enough to require long-term incarceration. It includes many reactor components, as well as chemical sludges and liquids from processing radioactive materials, which can often be solidified in concrete blocks. Once solid, intermediate waste can be buried safely in shallow graves, though anything containing plutonium will have to be disposed of deep underground because of the very long half-life.

Much of America’s intermediate-level waste will end up at the country’s largest deep-burial site for such radioactive material. The U.S. military’s Waste Isolation Pilot Plant in salt beds near Carlsbad, New Mexico, could eventually take 6.2 million cubic feet of waste. But it has had problems that have slowed progress and raised questions about its viability.

A chemical explosion in 2014 sprayed the tunnels dug into the salt beds with a white, radioactive foam. When a ventilation filter failed, some of the plutonium reached the surface, where at least 17 surface workers were contaminated. The military shut the tunnels for three years to clean up. While WIPP is today back in business, full operations cannot resume until a new ventilation system is in place, probably in 2021. The eventual cost of the accident, including keeping the dump open longer to catch up with the waste backlog, has been put at $2 billion.

High-level waste is the nastiest stuff. It includes all spent fuel and a range of highly radioactive waste liquids produced when spent fuel is reprocessed, a chemical treatment that extracts the plutonium. Most of America’s high-level waste liquids—and around 30 percent of the world’s total—are in tanks at Hanford.

High-level waste is either very radioactive and will stay so for a long time, or it generates heat and so requires keeping cool. Usually both. It accounts for more than 95 percent of all the radioactivity in America’s nuclear waste, and needs to be kept out of harm’s way for thousands of years.

There is general agreement that the only way to keep high-level waste safe is by turning the liquids into solids and then burying it all deep underground, somewhere where neither water nor seismic activity is likely to bring the radioactivity to the surface, and where nobody is likely to stumble on it unexpectedly. There is disagreement, however, about whether this buried waste should be kept retrievable in case future technologies could make it safer sooner, or whether accessibility simply places a burden of guardianship on future generations.

Before it can be buried, most high-level waste needs to be stored for up to a century while it cools. Unfortunately, this has encouraged countries to put off making plans. None of the world’s high-level waste currently has any permanent resting place. The planet is instead peppered with interim stores. America is no better. Its 90,000 metric tons of high-level waste—set to rise to as much as 140,000 tonnes by the time the last power plant closes—is mostly sitting in ponds at dozens of power stations or lockups like Fort St. Vrain.

How did the United States reach this impasse? Back in 1982, the Nuclear Waste Policy Act established that it was the government’s job to deal with this ultimate back-end problem. The act obliged Washington to begin removing used fuel from stores and other facilities by 1998 for eventual disposal at a federal facility. In 1987, Yucca Mountain, near the former Nevada bomb-testing grounds, was chosen to be the sole such facility.

In the 1990s, a five-mile tunnel was dug into the remote mountain. Then work stopped, in part because of vehement state opposition and in part because of concerns raised by geologists that a future volcanic eruption could propel buried waste back to the surface. One of President Obama’s first acts on taking office in 2009 was to formally abandon the $100 billion project. Things headed for the courts, which began awarding damages to power companies unable to make use of the nonexistent federal facility. The payouts amount to around half a billion dollars a year, and by 2022 will likely reach $29 billion.

Now President Trump wants to revive Yucca. His 2019 budget request included $120 million for the task. But the state opposition remains as strong as ever, and only $50 million was included in the final budget for Yucca-related items. Maybe Yucca Mountain will make a comeback. If not, then with no alternatives on the horizon, utilities will carry on being paid to keep spent fuel in pools next to abandoned nuclear power plants, and the interim stores in places such as Fort St. Vrain could be in business not just for decades but for centuries. The nuclear-waste time bomb will keep ticking.

The true heartland of America’s nuclear enterprise has always been Hanford. And it is the biggest and most toxic cleanup legacy too. Straddling the Columbia River, the Hanford nuclear reservation was America’s primary bomb-making factory. It was where they made the plutonium. At peak production, during the 1960s, its nine reactors irradiated 7,000 metric tons of uranium fuel annually. The intense radiation inside the reactors produced plutonium that was then extracted at five reprocessing plants. Hanford produced a total of 67 metric tons of the metal for the American arsenal, before business halted after the Cold War ended.

Plutonium production was a huge task. It required much of the electricity generated at the giant Grand Coulee Dam upstream on the Columbia, the largest hydroelectric power producer in the United States. And the mess left behind is equally mind-boggling. Since production ceased, Hanford has been conducting the country’s largest-ever environmental cleanup program. The current expenditure is $2.3 billion a year. By the time it is done the bill will be more than $100 billion.

The site holds an estimated 25 million cubic feet of solid, radioactive waste. Much of it is buried in over 40 miles of trenches and tunnels, up to 24 feet deep, including the stretch that caved in last year. Elsewhere, there are two corroding cooling ponds, each the size of an Olympic swimming pool, containing some 2,000 tons of spent fuel that never got reprocessed.

But the headline Hanford problem is the 56 million gallons of acidic and highly radioactive liquids and sludges, stored in 177 giant tanks, each up to 75 feet in diameter. They are the solvent leftovers from reprocessing, and contain around twice the total radioactivity released from the world’s worst nuclear accident to date, the 1986 explosion at the Chernobyl power station in Ukraine.

The tanks have been leaking for over half a century. Around a million gallons are slowly spreading toward the Columbia River, in a plume of contaminated soil covering 80 square miles. Protecting the river and its rich salmon habitat from the radioactive pollution is the number-one cleanup priority for the site’s custodians at the Department of Energy. To head off the flows, engineers are constantly pumping out radioactive water.

A better idea is to stop the leaks at the source by emptying the tanks and solidifying the liquids. The current aim is to heat them with glass-forming materials to create solid blocks that could one day be buried deep underground—maybe at Yucca Mountain. Work on a plant to do this began in 2002. It is currently 25 years behind schedule. Operations are not set to begin until 2036 and, once underway, would take 40 years.

At $17 billion and counting, the project is way over budget. Former plant engineers who have turned whistle-blowers believe it won’t be fit for the job and should be abandoned. They warn of a serious risk that particles of plutonium may settle out in the plant processing tanks, creating the potential for an accidental explosion with a big release of radiation.

The task at Hanford grows ever more daunting. After almost three decades, little of the waste and few of the tanks or processing plants have been cleaned up. Far away in Washington, D.C., some question the continuing money sink. It seems to some like a 21st-century pork barrel. Perhaps, critics say, it would be better to put up a fence and walk away. President Trump, while so far publicly supporting the Hanford cleanup, may privately agree. He has slashed its annual budget by $230 million, or about 10 percent.

Local environmentalists are scandalized. “We have got to clean up the site,” says Dan Serres, the conservation director of Columbia Riverkeeper, a local NGO. The tanks should be emptied and the trenches dug up. “In a hundred years, I’d hope the Native Americans have their treaty rights to this land restored,” agrees Chuck Johnson, of Physicians for Social Responsibility. But Tom Carpenter, the executive director of Hanford Challenge, who sits on an advisory board at the Hanford Concerns Council, told me: “You are never going to dig all the waste there up.” The tanks will have to be dealt with, but “most of Hanford’s waste volume-wise is going to stay put. Hanford is going to be a national sacrifice zone for hundreds of years.”

This piece is adapted from Pearce’s new book, Fallout: Disasters, Lies, and the Legacy of the Nuclear Age.