istock

The Ponds

Oil sands extraction makes a lot of waste. Where does it all go? Welcome to Alberta’s tailings ponds.

By Andrew Nikiforuk

EVERY ALBERTAN NOW KNOWS that the tar sands, the world’s largest energy project, drinks an enormous amount of water. Separating tar from sand is a messy, water intensive business: producing just one barrel of oil requires an average of three barrels of fresh water. Industry now withdraws enough from the Athabasca River every year to sustain a city of two million people. It’s instructive that the Alberta Energy Research Institute, an agency not known for its environmental radicalism, calls this addiction “unsustainable.”

Few citizens, however, know much about the surprising fate of this water. Incredibly, 90 per cent of it never sees a fish or duck again. After being used to separate tar from sand in the equivalent of large washing machines, the water has the consistency of toxic grey ketchup. To dispose of the waste, industry pipes it off to what engineers call “settling basins” or “tailings ponds.” With a little luck the water will separate from the slime and become fish-friendly within 150 years.

These ponds aren’t really ponds; they are man-made earthen dams. Not surprisingly, they uniquely constitute the largest collection of impoundments or dykes in the world. Nearly a dozen now line both sides of the Athabasca River and pose an enduring threat to the Mackenzie River Basin, Canada’s largest watershed. Many are also leaking and creating their own toxic wetlands. Their eventual reclamation remains an unsolved problem. Even the Alberta Chamber of Resources considers these primitive long-term storage ponds “a risk to the oil sands industry.” The ponds also explain why one oil sands executive, quoted anonymously in the journal Petroleum Economist in 2005, called his industry “an environmental freak show.”

LIKE EVERYTHING ABOUT THE TAR SANDS, the sheer scale of the tailings ponds boggles the imagination. According to the Alberta Chamber of Commerce, industry spits out six barrels of sand and one and a half barrels of fine tailings for every barrel of oil it makes. To accommodate all of that watery waste, companies have built massive flat-topped pyramids or dykes that tower above the forest floor. For example, the Sand Starter dyke that Canadian Natural Resources Ltd. plans to build for its horizon project will cover 3,580 hectares, with a peak height of 70 metres, and will eventually house one billion cubic metres of gunk.

From the air, these mysterious dams resemble the work of giant prehistoric beavers. during a recent tour of the tar sands, Stéphane dion, leader of the federal Liberal Party, mistook these waste ponds for natural lakes. It’s easy to understand why. The dykes range in size from 150 hectares to 3,000 hectares. To date, they have displaced approximately 50 square kilometres of forest and muskeg, says the Pembina Institute. Astronauts can see the dams from space.

Syncrude, the largest oil producer in the tar sands, owns the largest tailings pond, which redefine “large.” Every day, Syncrude dumps 250,000 tons of tailings into the Syncrude Tailings Dam, which the US Department of the Interior ranks as the world’s largest dam, based on volume of construction material. Completed in 1973, it is 22 kilometres long and holds 540 million cubic metres. Only when China completes the Three Gorges Dam next year (which has already submerged 13 major cities, 140 towns and 326 villages) will Syncrude lose its world record.

No one canoes, fishes or swims in these ponds, and for good reason. Every tailings pond contains polycyclic aromatic hydrocarbons (PAHs), naphthenic acids, heavy metals, salts and bitumen. Of 25 PAHs studied by the US Environmental Protec- tion Agency, 14 are true-blue human carcinogens. Both PAHs and naphthenic acids are potent fish-killers, too. The ubiquitous presence of PAHs in the tar sands prompted Jan Ciborowski, an aquatic ecologist and toxicologist at the University of Windsor, to make a remarkable calculation: he estimated that it would take seven million years for the local midge and black fly populations to metabolize all the industry’s cancer makers.

In a recent posting to an Internet forum, Stephen Borsy, who identified himself as a Calgary-based tar sands worker, said, “How these companies can say that they are ‘environmental friendly’ I’ll never understand… Even at minus 30 degrees this stuff doesn’t freeze. It sits there steaming. The stench from these ponds is indescribable. I’ve been there. I’ve seen it. I smelled it.”

After it’s been used to separate tar from sand, the water has the consistency of toxic grey ketchup.

Since 1968, the oil sands tailings ponds have been growing by leaps and bounds and now hold a total of 5.5 billion cubic metres of waste and water. (About 70 per cent of that volume is water.) By 2020, Syncrude and Suncor alone will have added another billion cubic metres to the ponds. Jim Byrne, a water expert at the University of Lethbridge, recently calculated that if Alberta drained its tar sands waste into Lake Erie, it would fill the basin to a depth of 20 centimetres. By 2030, this toxic soup would be nearly two metres deep. Not many nations other than China can claim such records of waste production.

LAST FALL, JOHN SEMPLE, a fort McMurray outfitter and longtime resident of the boom town, took me upriver to show me one of industry’s oldest tailings ponds. Just outside the Suncor site, where the trees disappear and hydrocarbons fill the air, Semple killed his boat’s motor and pointed out an odd, cone-shaped hill on the west bank of the river. “This was an island once, in the middle of the river.” he explained. Local Cree and Métis called it Tar Island because bitumen oozed down its banks. But in the late 1960s Suncor rerouted the river around the island in order to build a tailings pond. To this day, Semple doesn’t understand why Environment Canada allowed the construction of such an impoundment so close to the Athabasca. “There is stuff coming off there (the dyke) into the river.”

The Tar Island dyke was essentially an experiment in how to build a holding pond for toxic tar sands waste. Engineers not only miscalculated how long they would need the dyke (they thought a few years would be enough), but also underestimated the behaviour and sheer volume of the tailings. So a dyke originally designed to be only 12 metres tall now towers over the river at 99 metres and stretches 3.5 kilometres long.

The dyke has experienced several problems over the years, including something called “deformation creep.” Norbert Morgenstern, a highly respected geotechnical engineer and tailings pond expert, explains that “creep” is movement in the dam’s foundations. To stop the creep, Suncor recently built a small berm at the toe of the dyke.

According to Morgenstern, the Tar Island Dyke reflects “incremental learning in the industry.” At one point the original dyke even drained toxic waste directly into the river. Now, as Semple guessed, toxins just seep into the Athabasca River from the bottom of the dyke. “There is leakage,” confirms Morgenstern.

In 2001, Morgenstern published a paper on tailings ponds. He concluded that many of the ponds have failed, that their reliability is “among the lowest of earth structures” and that “a well-intentioned corporation employing apparently well- qualified consultants is not adequate insurance against serious incidents.” However, Morgenstern, who sits on Alberta’s dam safety committee, didn’t think these conclusions readily applied to the tar sands.

Others aren’t quite so confident. At a 2005 conference on geotechnical engineering for disaster mitigation, two Iranian engineers reported the results of a study at the Syncrude Tailings Dam and concluded “that the tailings dam and foundation are comparatively in a more critical condition with respect to yield zones, displacements and strains” than expected. Other engineers have expressed worries about the “significant design challenges” posed by building raised toxic lakes on top of large Pleistocene glacial meltwater channel deposits, a common practice in the tar sands. At a 2006 remediation technologies symposium, four Canadian engineers revealed that one dyke was leaking naphthenic acids, trace metals and ammonium into groundwater.

Perhaps the biggest fear is an accidental breach. Earthquakes and extreme weather events, of course, can make rubble of even the best-engineered dykes. “If any of those [tailings ponds] were ever to breach and discharge into the river, the world would forever forget about the Exxon Valdez,” notes David Schindler, one of the world’s most respected water ecologists. (The Exxon Valdez oil tanker struck a reef in 1989, releasing 11 million gallons of crude into Prince William Sound, Alaska.)

But for now leaks remain a constant challenge. As one 2004 scientific paper by oil sands engineers admitted: “all tailings impoundments leak, even if lined, and the amount and nature of the seepage dictates the method of reclamation.”

Most tar sands tailings ponds are now leaking so badly that they’ve even created their their own wetlands around their moat-encircled foundations. Although cattails and hum- mock grass thrive in the effluent, other organisms don’t. A 1999 study in the journal Ecological Applications found that indigenous fish were “unable to survive in wetlands containing oil sands effluent.” In other words, they died. When a group of researchers put tadpoles in these oil sands wetlands, the creatures either expired or grew abnormally slowly. Plant experiments have also yielded discouraging results. A study by Simon Fraser University scientists found that oil sands wetlands inhibit the germination of tomato, clover, wheat, rye, peas, canary grass and loblolly pine. Concluded the scientists: “The negative effects of the effluents on seed germination may account for the paucity of aquatic species that have invaded the oil-sands-impacted wetlands.”

Birds haven’t fared much better. One 2003 study looked at how tree swallows thrived in a normal wetland versus one made by oil sands tailings. The findings didn’t surprise anyone. During a bout of harsh weather, mortality rates reached 48 per cent among swallows in a normal marsh. But the death rate ranged between 59 per cent and 100 per cent in wetlands made of tailings pond seepage. The scientists concluded that nestlings from these wetlands “may be less able to withstand additional stressors, which could decrease their chances of survival after fledging.”

“Even at minus 30 degrees this stuff doesn’t freeze. It sits there steaming. The stench is indescribable.”

Seepage is not just a short-term problem. In 2004, when Suncor proposed to build its South Tailings Pond to accommodate waste from its Millennium Mine, its engineers admitted to the Energy & Utilities Board (EUB) that the 1,900-hectare site would hold 350 million cubic metres of gunk—and yes, it would seep. Moreover, seepage into groundwater could “change water quality in the lower portion of McLean Creek and could therefore impact the health of aquatic life, terrestrial wildlife and humans.” To prevent groundwater contamination, Suncor devised a fancy reverse-pumping system that put contaminants back into its pond. But the Suncor engineers predicted that even after the closure of the mine they would have to maintain a “seepage interception system” for 60 years or longer.

Under the Migratory Birds Convention Act, 1994, it’s against the law to kill birds by sliming them with oil or other toxic waste. A tundra swan or snow goose coated in bitumen either drowns or dies of hypothermia. But to a bird’s eye, the toxic ponds in the spring look like a nice bit of ice-free real estate. So for years the tar sands industry has employed human scarecrows and propane cannons to keep migratory birds off its ponds. The birds, however, got used to the propane cannons, and continued to die by the hundreds every year. Albian Sands, which has just built its own toxic lake, recently developed a new “on-demand radar-based bird deterrent system.” Under this scheme, flying birds activate a radar system which in turn sets off a combination of deterrents including scare cannons, robotic falcons powered by solar panels, flashing lights and recorded attack calls. This system is about five times more effective than scarecrows. But the best deterrent is simply not to make toxic tailings ponds, says University of Alberta biology researcher Colleen Cassady St. Clair, who’s studied the problem. But tar sands technology that doesn’t make toxic lakes “is likely to be at least 10 years away.”

INDUSTRY HAS TRIED MANY DIFFERENT TRICKS to get the ponds to settle more quickly and lose their toxicity. They’ve freeze-dried tailings, added bacteria and even poured in chemical stabilizers such as gypsum. But more research is needed. Many companies now hope to empty their salty tailings waste into end-pit lakes, which the EUB calls “a complex and as yet unproven concept.”

Canada’s record on the reclamation of northern mines has not been inspiring. In 2002 the federal Auditor General reported that negligent and understaffed regulators had let companies walk away from lakes of arsenic and cyanide at abandoned mine sites throughout the north. “The financial burden of dealing with the legacy of northern abandoned mines is huge, and the federal government has not yet come to grips with it,” added the Auditor General. The Alberta government, which holds less than half a billion in security bonds for $100-billion worth of mines, sheepishly admits that it’s still working on a plan: “Reclamation guidelines and a land capability evaluation system for reclaimed oil sands landscapes are currently under development and review. As well, discussions are occurring on developing reclamation criteria tailored to the oil sands area.” The National Energy Board predicts that the reclaimed landscape will contain 10 per cent fewer wetlands and notes “there is still some debate about whether the tailings ponds can become biologically productive ecosystems.”

Four years ago, a group of scientists gathered in Fort McMurray to discuss the future of the tailings ponds and how to turn them into functioning wetlands again. For two days the scientists talked about the challenges posed by salts, PAhs and naphthenic acids. Most acknowledged that climate change would rob the region of the clean water necessary for effective reclamation. In the end the scientists identified two sobering weaknesses: “that this entire mining process is allowed to proceed with little understanding of how it will be reclaimed” and that far too little money “is going into reclamation solutions, given the scale of the problem.”

Those liabilities remain unchanged.

Andrew Nikiforuk’s most recent book, Pandemonium, examines the consequences of increased global traffic in living organisms.

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