Insinyur Dapat Membangun Situs untuk Mengamankan Limbah Nuklir selama 100.000 Tahun. Siapa yang Akan Tinggal di Dekatnya?

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The world’s first permanent depository for nuclear fuel waste opens later this year on Olkiluoto, a sparsely populated and lushly forested island in the Baltic Sea three hours north of Helsinki.

Onkalo — the name means “cavity” or “cave” in Finnish — is among the most advanced facilities of its kind, designed for an unprecedented and urgent task: safely storing some of the most toxic material on Earth nearly 1,500 feet underground in what’s called a deep mined geologic repository.

The process requires remarkable feats of engineering. It begins in an encapsulation plant, where robots remove spent nuclear fuel rods from storage canisters and place them in copper and cast iron casks up to two stories tall. Once full, these hefty vessels, weighing around 24 metric tons, will descend more than a quarter-mile in an elevator to a cavern hollowed out of crystalline bedrock 2 billion years old. (The trip takes 50 minutes.) Each tomb will hold 30 to 40 of these enormous containers ensconced in bentonite clay and sealed behind concrete. As many as 3,250 canisters containing 6,500 metric tons of humanity’s most dangerous refuse will, the theory goes, lie undisturbed for hundreds of thousands of years.

Nothing assembled by human hands has stood for more than a fraction of that. The world’s oldest known structure, Gobekli Tepe in Turkey, is a bit more than 11,000 years old. Designing Onkalo to endure for so unfathomably long is necessary because the material left behind by nuclear fission remains radioactive for millennia. Safely disposing of it requires stashing it for, essentially, eternity. That way nothing — be it natural disasters, future ice ages, or even the end of humanity itself — would expose anyone, or anything, to its dangers.

“The plan is that there will be no sign [of the facility],” said Pasi Tuohimaa, communications manager for Posiva, the agency that manages Finland’s nuclear waste. “Nobody would even know it’s there, whether we’re talking about future generations or future aliens or whatever.”

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Workers inspect the Repository in Onkalo.

Building such a place, as technologically complex as it is, might be easier than convincing a community to host it. Gaining that approval can take decades and rests upon a simple premise.

“One of the principles of geologic disposal is the idea that the generations that enjoy the benefits of nuclear power should also pay for and participate in the solution,” said Rodney Ewing, a mineralogist and materials scientist at Stanford University and co-director of the university’s Center for International Security and Cooperation.

The long process of gaining such support is called consent-based siting, an undertaking many in the nuclear energy sector consider vital as the world abandons fossil fuels. Nuclear power accounts for almost a fifth of the United States’ electricity generation, and its expansion is among the few elements of the Biden administration’s energy agenda that enjoys strong bipartisan support. Over the last year, Energy Secretary Jennifer Granholm has touted the nation’s newest reactor, celebrated plans for an experimental small modular reactor, and unveiled a $1.5 billion loan to restart a defunct plant in Michigan.

These are hardly one-offs. The U.S. intends to triple its nuclear energy capacity by 2050. Yet experts say there isn’t enough public discussion of how to deal with the corresponding increase in radioactive trash, which will compound a problem the country has deferred since the start of the nuclear age. After botching plans for a deep mined geological repository a generation ago, the United States is scrambling to catch up to Finland and several other nations, including Canada, which could choose a site by year’s end.

As the U.S. races toward a post-carbon future in which nuclear energy could play a key role, policymakers, energy experts, and community leaders say dealing with the inevitable waste isn’t a technical problem, but a social one. Engineers know how to build a repository capable of safeguarding the public for millennia. The bigger challenge is convincing people that it’s safe to live next to it.

The United States knew, even before the world’s first commercial nuclear power plant began operating in Pennsylvania in 1957, how best to dispose of the effluvium generated by splitting atoms to generate electricity. Earlier that year, geologists and geophysicists wrote a National Academy of Sciences report that proposed burying it. Opinions haven’t changed much in the 67 years since.

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“The only viable way to possibly deal with the issue of isolating radioactive waste that can remain hazardous for hundreds of thousands of years from the environment is a deep geologic repository,” said Edwin Lyman, director of nuclear power safety at the Union of Concerned Scientists. “There’s really no alternative.”

Yet this refuse, most of it from the nation’s 54 commercial reactors, remains in what amounts to cold storage. Depleted fuel rods are kept on-site in water tanks for about half a decade, then moved to steel and concrete canisters called dry casks and held for another 40 years in what’s known as interim storage. Only then is the material cool enough to stash underground. That last step has never happened, however. The nation’s 85 interim storage sites hold more than 86,000 tons of waste, a situation that’s akin to leaving your trash behind the garage indefinitely. The situation could grow more dire as the nation invests in advanced small modular reactors.

“It’s a pet peeve of mine, to be honest,” said Paul Murray, who became the Department of Energy’s deputy assistant secretary for spent fuel and waste disposition in October. “Everybody talks about the shiny new reactors, but nobody ever talks about back-end management of the fuel that comes out of them.”

Congress attempted to rectify that in 1982 when it passed the Nuclear Waste Policy Act. President Ronald Reagan called the law “an important step in the pursuit of the peaceful uses of atomic energy.” It required that the federal government begin taking responsibility for the nation’s nuclear waste by 1998, and that the utilities generating it pay a fee of one-tenth of a cent per kilowatt-hour of nuclear-generated electricity to be rid of it. The plan stalled because the government never took possession of most of the waste. That failure has allowed the utilities to collect $500 million in fines from Washington each year since 1998. A report that the Government Accountability Office released in 2021 noted that federal liabilities could reach $60 billion by 2030.

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The federal government’s missteps continued when plans for a deep geologic repository derailed about 15 years ago. The 1982 law directed the Department of Energy to provide the president, Congress, the Nuclear Regulatory Commission, and the Environmental Protection Agency with suggestions for several sites. Congress amended the law in 1987 to designate one: Yucca Mountain, about 100 miles northwest of Las Vegas on land the Western Shoshone Nation considers sacred.

This top-down process was the antithesis of consent-based siting, and it collapsed amid community opposition and the efforts of then-Senate Majority Leader Harry Reid. The Nevada Democrat convinced President Obama to scuttle the proposal, which by that point had cost $13 billion. The Obama administration convened a panel of scientists to devise a new plan; in 2012, it suggested creating an independent agency, giving it responsibility for the nuclear fund and directing it to revamp the effort through consent-based siting.

That recommendation mimicked what Finland had done, and Canada was doing, to build community consensus. Posiva spent four decades working toward the facility on Olkiluoto; the Canadian search started 24 years ago with the creation of the independent Nuclear Waste Management Organization. Yet more than 10 years after the Department of Energy made consent-based siting its official policy, there’s been little progress toward a deep mined geologic repository in the U.S. for commercial nuclear waste. (Radioactive refuse generated by the defense industry has, since 1999, been secured 2,150 feet underground at the Waste Isolation Pilot Plant in New Mexico.)

Instead of identifying possible sites for a deep geologic repository, the Energy Department directed Murray, who has a background in nuclear technology and environmental stewardship, to address a backlog of waste that could, by his estimate, take 55 years to clear out of interim storage. Much of this trash is languishing in dry casks that dot power plants in 37 states. Last year, he formed a 12-member Consent-Based Siting Consortia to start the search for a federally-managed site that…