Huge Ponds Hold Tar Sands Sludge, and Great Risks (Op-Ed)
Danielle Droitsch is director of the Canada Project for the NRDC. She contributed this article to Live Science's Expert Voices: Op-Ed & Insights.
On August 4, 2014, the catastrophic failure of a mining company's dam in British Columbia, Canada, released over 2.5 billion gallons of contaminated water from a containment pond into the upper Fraser River watershed. Only a few hundred miles east in Alberta, at least half a dozen dams containing the wastewater from the tar sands mining industry hold more than 100 times the volume of the British Columbia release and span over 43,000 acres of Canada's boreal forest. A breach from any one of these mine-tailings ponds would pose enormous risks to local communities and the surrounding boreal forest ecosystem.
And yet, Canadian authorities offer virtually no public information about the safety of these tailings dams, which already leak millions of gallons of wastewater — containing a suite of toxins, such as naphthenic acids, polycyclic aromatic hydrocarbons, phenolic compounds, ammonia and mercury — every day. Meanwhile, Canadian regulators have opted not to enforce existing laws meant to limit the volume of toxic waste produced during tar sands mining or confront the leaks. Canada's Pembina Institute projects that the volume of tailings will grow by at least 40 percent over the next two decades. By 2060, Pembina estimates that these mine-tailings ponds, which lie amidst the Canadian boreal landscape, will grow by another 120 billion gallons. [A Clear Signal Against the Use of Tar Sands ]
The tailings liability
The tar sands industry's tailings problem is a growing liability and it is getting worse. The mining operations generate massive volumes naphthenic acids, polycyclic aromatic hydrocarbons, phenolic compounds, ammonia, and mercury and other trace metals, and some of these compounds are carcinogenic. For every barrel of tar sands bitumen produced (the semi-solid substance from which tar sands oil is eventually refined), 1.5 barrels of liquid waste is added to the tailings ponds. According to the Pembina Institute, at current production levels, this means that every single day, mining operations have to store 6.6 million more gallons of tailings.
Already, more than 200 billion gallons of this liquid byproduct is stored behind those massive tailing dams, covering an area larger than Washington, D.C. According to Pembina, because of weak and unenforced regulations, the volume of tailings could grow to 343 billion gallons by 2060.
The risks from the ponds are well known. Last year, ecologist David Schindler of the University of Alberta, one of Canada's renowned water scientists, warned that a tar sands tailing breach was a huge threat. In 2013, the University of California’s Rosenburg Forum which convenes international water experts to tackle some of the world's most challenging water issues evaluated threats to the Mackenzie river basin (where the tar sands are located) and concluded, "… the largest single threat to the Mackenzie River Basin would be a large breach in the tailings ponds at one of the sites where surface mining bitumen is conducted."
Northern communities living downstream from these massive tailings dams are aware and concerned about risks presented by the tar-sands industry upstream. A larger spill could threaten not just the Athabasca river but the Peace-Athabasca delta, Lake Athabasca, the Slave river and delta, Great Slave Lake, and the Mackenzie river and delta, all of which empty into the Beaufort sea. Cleaning such a spill could cost billions of dollars.
Public information is lacking
Worldwide, major failures of tailings dams — like the recent one in British Columbia — occur at a frequency of two to five per year (there are approximately 3,500 tailings dams worldwide) while 35 smaller breaches occur annually. This is a much higher failure rate than experienced by water supply or hydroelectric dams. And Canada hasn't escaped this problem.
Just last year, a massive breach of tailings pond dam from an Alberta coal mine operation dumped 177 million gallons of water and 9.8 million gallons of sediment into the Athabasca watershed (the same watershed threatened by tar sands tailings). Despite an ongoing investigation, the cause of the 2013 breach is still unknown, though critics claim that a lack of government oversight is partly to blame.
Generally, a number of risk factors can lead to tailings dam failures. These include:
- While public bodies often own conventional dams, tailings dam are often owned and constructed by private mining companies who view the dams as a money-draining part of their operations.
- Unlike conventional dams, tailings dams can have a lifetime of hundreds of years and are considered permanent fixtures on landscapes. A conventional dam typically has a lifetime of less than 100 years.
- While conventional dams are constructed over a relatively short period, mining dams are constructed continuously over many years. As an example, the Suncor Tar Island tailings dam, originally intended to be 12 meters tall and be in use for only 3 years, has now risen to 91 meters and is more than 40 years old.
Tailings dams information is lacking
Canadian authorities share little information about the safety of tar-sands-tailings lakes. According the Pembina Institute, key documents like emergency preparedness plans, emergency response plans, operations and maintenance manuals, tailings-dam performance reports, and dam safety reviews are kept confidential for proprietary reasons. But according to the institute, "The difficulty in acquiring information on tar sands tailings dams, combined with the government of Alberta not publicly addressing concerns on tailings dam stability, limits the possibility for fair public scrutiny and independent dam assessment. Thus, the public is left to trust that tailings dams are safely constructed and maintained and that adequate plans for emergencies are in place."
And to be clear, tar sands tailings dams haven't escaped problems. Three major accidents have been reported, all in the 1970s, due to factors such as slope instability and foundation weakness. However, there is no public information about these events or the volume of tailings that was released.
Tailings ponds are already leaking
While the public has little information about the risk of a breach, the regulation of tar-sands tailings dams is dismal. A 2008 study by Environmental Defence Canada, based on industry data, found that as much as 2.9 million gallons of water leaks from tar sands tailings ponds into the environment every day, with no enforcement by the government. New federal research by Environment Canada, released in February 2014, confirms that leaking tailings ponds are leaching into groundwater and then into the Athabasca river.
Even the weakest regulations on the books, designed to limit the volume of tailings waste, aren't enforced. There are news reports on how the tar sands industry is not complying with these regulations and Alberta regulators have announced they will not enforce the regulations first introduced in 2009.
Canadian authorities looking the other way
Perhaps most distressing is how Canadian federal authorities treat the tar-sands tailings problem. A petition filed by NRDC and Environmental Defence Canada in 2010 with the Commission on Environmental Cooperation (CEC), a NAFTA oversight body, raised concerns about the leaking tailings ponds and the failure of federal government authorities to enforce its clean water laws. Recently, the CEC agreed to pursue an investigation, but in a shocking response, the Canadian government has not only refused to participate in the investigation but has announced it will fight to keep the investigation from happening.
And while the government has no plans to eliminate tailings from the tar sands production process, last year Alberta's premier traveled to Washington, D.C. to disingenuously claim that tailings dams would "disappear from Alberta's landscape in the near future." It is no secret the Alberta government has failed to enforce its tailings regulations but its communication materials suggest they are enforcing the law. And despite clear evidence to the contrary, the Alberta government denies there is even a problem with leaking tailings ponds.
All of this leaves the public in both Canada and the United States with a strong impression that Albertan and federal Canadian regulators are, at best, ignoring the alarming growth of tailings waste and the fact that the ponds are leaking. This willful ignorance, coupled with the lack of public information about safety measures in place to prevent against a breach, does not inspire confidence that authorities are minding the store. It is in this atmosphere that the public has a right to demand information so they can learn about the risks of a catastrophic breach of a tar sands tailing dam and push for actions to prevent it from ever happening.
Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook, Twitter and Google +. The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on Live Science.
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