The Plan to Build a Million-Year Nuclear Waste Dump on the Great Lakes

Kincardine is a postcard-perfect spot on the Ontario shores of Lake Huron, home to about 11,000 people. It's in farming and cottage country, known for its sandy beaches, for its playhouse, for the Scottish-themed festival it hosts each July.

Kincardine is also synonymous with nuclear power, as one of the province's three operating nuclear facilities—the Bruce Nuclear Generating Station—is a stone's throw away. Lots of people in town work at the Bruce, as the facility is commonly called, and have grown up with the nuclear industry as part of the background fabric of their daily lives.

Soon, Kincardine could be known for something other than its quaint wooden lighthouse: a nuclear waste vault, buried 680 meters (2,230 feet) underground. Radioactive garbage would be stashed there for a million years or longer, about 1 kilometre from the lake.

"It does not get better than the Bruce site," Earth scientist Mark Jensen, who's been involved in this project since 2002, and is now director of DGR Geoscience and Research for Canada's Nuclear Waste Management Organization, told me in an interview. "The site is exceptional. It's ancient, stable, resilient, and will be for a long time."

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Local politicians in Canada support the proposal. Ontario Power Generation (OPG), which owns three nuclear facilities in the province, including the Bruce, says it's the best option too. Right now, Ontario's nuclear waste is waiting for a long-term plan.

But there are also plenty of people who are fiercely against the DGR. Critics on both sides of the border point out that the Great Lakes provide drinking water for 40 million people, and that Canada is a big country—surely there must be somewhere else, they say, to store this waste. In March, Congressman Dan Kildee and Senators Gary Peter and Debbie Stabenow, all Michigan Democrats, introduced resolutions in the House and Senate opposing it.

Despite best practices, accidents do happen. In 2014, a comparable facility in New Mexico leaked a small amount of radiation after a storage container was packed improperly. Although most of the waste material was contained within the facility, the resulting cleanup closed the plant for nearly three years, and cost hundreds of millions of taxpayer dollars.

The debate over the fate of our nuclear waste comes at a critical time, when many governments are trying to wean off fossil fuels. (Ontario phased out coal in 2014 in a bid to move toward cleaner energy, and now about 60 percent of its power comes from nuclear.)

"The number one problem facing us as a species is climate change," Allison Macfarlane, who was Chairman of the US Nuclear Regulatory Commission (NRC) under President Barack Obama, told me in an interview. "That's the big one. And nuclear certainly helps with that, because it produces energy without producing carbon."

For all the growing enthusiasm around nuclear power, there remains a glaring problem: what to do about the waste, which will be around long after the rest of us are gone. How do you future-proof an underground vault for a million years?

Nuclear garbage can be divided into three broad categories: low, intermediate, and high-level waste. The low- and intermediate-level is stuff like mop heads, irradiated clothing, machine parts, filters, or certain resins. High-level waste is spent nuclear fuel.

Some waste loses its radioactivity fairly quickly (low-level waste is radioactive for three centuries), but the higher-level stuff won't be safe for hundreds of thousands of years.

OPG produces most of the low- and intermediate-level waste in Canada. Right now, it's transported to the Bruce site, turned to ash, and sealed inside containers at the Western Waste Management Facility, which is licensed by federal regulators. OPG wants to bury this waste so it can be forgotten, essentially forever. (Regulators are looking at a separate DGR for Canada's high-level waste, which is currently stored on-site at the reactors where it was produced. That plan, though, is still years away.)

The DGR would be deeper underground than the CN Tower is tall. OPG says it would be ensconced in "impenetrable rock," and "have no impact on the surrounding environment," including Lake Huron. It's hard not to be impressed by what's involved in planning on the timescales involved: scientists have modelled what could happen over the next million years, ensuring the DGR would withstand the weight of future glaciers that will one day again settle over the landscape of Ontario, as they did in past Ice Ages, Jensen told me.

His confidence stems partly from the quality of the rock that would surround it—but that's also one of the more controversial elements of this plan. The DGR at Kincardine would be mainly ensconced in what he calls "low-permeability limestone," the first nuclear vault anywhere in the world in this type of rock, and at this depth.

The geological setting is ideal, Jensen believes. "It represents sediments that were laid in ancient oceans, almost flat, and are essentially still that way today," he said—what he described as a "layercake" of rock that is regular and undeformed. Layers of bedrock are "hundreds of metres thick," he said, and extend tens of kilometres in every direction, providing "containment and isolation" from the surface.

According to Jensen, these are some of the lowest-permeability rocks ever measured on the globe, with "essentially no groundwater flow."

Critics like architect Jill Taylor disagree. Taylor leads SOS Great Lakes, a coalition against the burial of nuclear waste "anywhere in the Great Lakes basin," as she told me. "The whole concept of DGRs is not proven," and they have leaked in the past, Taylor added. She cites the 2014 leak in New Mexico, at a facility called the Waste Isolation Pilot Plant, or WIPP, as a cautionary tale.

"OPG is saying the best rock in the world is limestone, which is entirely unproven," Taylor contended, as no DGRs operate in similar environments elsewhere. In fact, there are a handful of DGRs either planned or underway elsewhere in the world. Beyond New Mexico, Jensen said Ontario's plan is comparable to the Konrad repository, in Germany, a former iron mine that's being repurposed for nuclear waste. It's now under construction.

The WIPP incident speaks to the risks of human error. A leak so close to Lake Huron, Taylor believes, could be disastrous. "The Great Lakes are the largest freshwater body on the planet," said Taylor, who thinks OPG should keep all of its nuclear waste away from the Great Lakes. She also argues the waste should stay retrievable, so future generations can keep tabs on it.

After years of intense scrutiny, Canadian regulators aren't yet convinced of OPG's plan. In 2016, they asked the Crown corporation to evaluate alternate sites where the DGR could be placed. OPG returned with a report that critics derided for its vagueness, evaluating two possible sites, labelled "crystalline" and "sedimentary," for the rock.

The same report said it would cost billions of dollars to transport the waste to another site, and raised the spectre of traffic accidents involving nuclear waste on the highway if it's moved.

In April, the Canadian Environmental Assessment Agency (CEAA) essentially sent OPG back to the drawing board, yet again. A decision on the fate of the Kincardine DGR, which some thought could come at the end of this year, now seems likely to take longer.

In the meantime, people continue to fret about what would happen in the worst-case scenario. What if the DGR were built and, similarly to what happened a few years ago in the American southwest, there was a leak of radioactive material?

On Valentine's Day, 2014, unusually high levels of radiation were detected by underground air monitoring systems at the Waste Isolation Pilot Plant in Carlsbad, New Mexico. This caused the air system to automatically switch to filtration mode and route the air in that part of the facility to HEPA filter tanks, which remove ultrafine particles from the air. Still, the following day, trace amounts of americium and plutonium were found above-ground at air quality stations about half-a-mile from the WIPP.

In total, 22 employees were exposed to radiation, and 13 tested positive for low-level contamination, although the health effects of this exposure were considered minor.

The leak came at a challenging time for OPG, which was trying to convince people of its DGR plan near Kincardine, and had cited the New Mexico facility as an example of a successful and comparable operation in its regulatory filings, according to The Toronto Star.

Critics still raise this costly accident as a case-in-point of the inherent danger in storing nuclear waste deep underground. What went wrong in Carlsbad, though, doesn't seem to have been a failing of design. It was ultimately chalked up to human error.

Following initial puzzlement over what had caused the leak, the answer, it turned out, was kitty litter—organic kitty litter. Nuclear waste can be couched in clay kitty litter for transport and storage to absorb liquid residue, but organic litter contains plant material, and this created a chemical reaction that caused the waste's storage container to burst open.

Seven ounces of waste was released, travelling more than 3,000 feet through the air in the tunnels.

But based on numerous reports, the WIPP functioned perfectly in the aftermath of the leak, and 99.97 percent of the radioactive waste was prevented from exiting the facility. Still, it only resumed operations this February after nearly three years of cleanup, with an estimated cost of about $2 billion after everything's said and done, and left many people understandably skittish about nuclear waste storage underground.

The plans for WIPP date back to 1973, when the US government began investigating a large salt formation in the American southwest as a candidate site for a DGR.

"The thick salt in the Permian Basin was thought to be a good repository because any heat put out by the material would actually melt the salt and help seal the repository even more," said Victor Baker, a professor of planetary surfaces at the University of Arizona who helped review potential DGR sites in the 80s. "And the salt is there because there hasn't been any water flowing through the area for millions of years."

After six years of prospecting, a final site was selected in 1979 and construction began. But in spite of the geological soundness of the site, there were grumblings elsewhere. Locals weren't sure how much they could trust the government to tell them the truth about what was going on.

The New Mexico Environmental Evaluation Group was formed as an independent organization tasked with answering the public's questions, as well as verifying facts and any studies conducted by the US Department of Energy.

By 1988, excavation and construction of the 56 storage halls that comprise the facility had finished, and small amounts of low-level waste began to be transferred to the WIPP for rigorous testing. After a decade, the first shipment of nuclear waste intended for permanent storage arrived from Los Alamos National Laboratory, the notorious design site for nuclear weapons in New Mexico.

The WIPP operated without a hitch for the next 15 years, taking in some 91,000 cubic meters of low- and mid-level waste, the equivalent of about 450,000 55-gallon drums. But even with the best intentions, accidents happen. And when we're talking about a timeline extending hundreds of thousands of years, there's ample opportunity for a number of accidents to befall even the best-planned DGR. Yet the WIPP is a testament to the idea that with careful planning, these accidents needn't become disasters.

Macfarlane, Obama's appointee as NRC Chairman, wouldn't comment specifically on Kincardine's proposed DGR. But she did emphasize that this type of underground storage is generally the best option for long-term disposal of nuclear waste.

"What's the alternative? To leave it where it is?" said Macfarlane, a geologist who is now based at George Washington University. "Then it's 100 percent guaranteed to get into the environment. Some people say, let's wait until we know more," and then make a plan, she continued. "Well, the physics isn't going to change. The danger you run into, when you wait, is that you don't have as responsible a government to manage the material."

These questions are crucial with Donald Trump in the White House. The reality television personality and current US president has revived a controversial plan to bury high-level nuclear waste at Yucca Mountain, in Nevada, despite massive local opposition and concern from scientists—including Macfarlane—who say the site is unsuitable.

Not only is Yucca Mountain in a seismically and volcanically active region, Macfarlane told me, "it's an oxidizing environment," which would create potentially unstable conditions for nuclear waste. Yet, for political reasons, the once-dead plan seems to be back on the table.

Canadian regulators, meanwhile, need to decide what to do with this country's nuclear waste, instead of just kicking the can down the road. At the earliest, the Kincardine DGR could become operational and begin to accept waste in 2026.

For better or worse, our species has decided that nuclear energy and bombs are worth pursuing, in spite of the deadly waste created in the process. With the growing pressure of climate change, nuclear looks like an attractive option in many respects. But the price we pay is that we must deal with the waste. Stashing it in temporary, surface-level containers works for now, but this problem exists on a geologic timescale—and requires geologic solutions.

If we want to continue consuming power at the rate that we do, we'll have to deal with it head-on.

"There are environmental costs and human costs to every kind [of energy]," including nuclear, Macfarlane told me. "There is no free lunch."

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