A Tale of Two Disasters: Coal Ash and Tar Sands Tailings
by David Sassoon - Dec 29th, 2008
Coal ash deposits in the USA are now under renewed scrutiny after a giant spill just before Christmas released 5.4 million cubic yards of toxic sludge into Tennessee waterways. Water tests near the spill from the Kingston Fossil Plant showed elevated levels of lead and thallium, which can cause birth defects and nervous and reproductive system disorders. The spill muddied the waters in the Emory river and is flowing into tributaries of the Tennessee River - the water supply for Chattanooga and millions of people living downstream in Alabama, Tennessee and Kentucky.
So now a big question mark hangs over the hundreds of coal plants all across the country which store their fly ash in unlined embankments and ponds -- like the one that failed last week. Most are situated near rivers that supply water needed by the coal plants to operate.
The NY Times reported that in the US, coal plants produce 129 million tons of postcombustion byproducts a year. It's the second-largest waste stream in the country, after municipal solid waste, and its storage and handling is unregulated. Who knew?
It is yet another measure of the high price of addiction to fossil fuels, which is not only polluting the air and warming the earth, but fouling the nation's terrestrial and aquatic environment as well. The Tennessee coal spill is a wake up call not only for the coal industry, but the oil industry as well, and not only for America but for Canada, too.
Both nations, still in pursuit of endless supplies of fossil energy, are collaborating on the exploitation of Alberta's tar sands -- one of whose byproducts will be toxic spills like the one in Tennessee, only on a massively larger scale.
In Alberta, visible from outer space, are 23 squares miles of unstable, unregulated and leaking man-made "tailings ponds" holding the toxic leavings of the mining process. A dam breach is only a matter of time.
Required reading on this subject is Andrew Nikiforuk's new book Tar Sands: Dirty Oil and the Future of a Continent, recently published to wide acclaim in Canada and set for US release in March. In this context, one chapter in particular called "The Ponds" is of direct and chilling relevance.
...there is no denying that the world's biggest energy project has spawned one of the world's most fantastic concentrations of toxic waste, producing enough sludge every day (400 million gallons) to fill 720 Olympic pools....
The ponds are truly a wonder of geotechnical engineering. Made from earth stripped off the top of open-pit mines, they rise an average of 270 feet above the forest floor like strange, flat-topped pyramids. By now, the ponds hold more than four decades worth of contaminated water, sand and bitumen.....
The ponds are a byproduct of bad design and industry's profligate water abuse. Of the twelve barrels of water needed to make one barrel of bitumen, approximately three barrels become mudlike tailings....
Perhaps the biggest enviromental risk is an accidental breach. Earthquakes and extreme weather events can make a rubble of even the best-engineered dykes and could cause a domino-like failure of other nearby ponds....
Engineers and ecologists agree that the tailings ponds pose a substantial risk to Canada's largest river basin....
For now leaks from the ponds remain a constant challenge....most tar sands tailings ponds seep so badly that they've created toxic wetlands near their bases.
The ponds became world famous earlier this year when 500 migrating ducks landed on one of them. As Nikiforuk recounts, "Many of the migrating visitors were buffleheads, keen divers that slipped under the water and never resurfaced." It wasn't long before the Prime Minister was apologizing. But of course, nothing much has changed. The tailings ponds continue to grow at a daily pace that is mind-boggling.
Meanwhile, in Tennessee, the clean-up of the toxic coal ash is continuing. But let's not kid ourselves -- that's not the real disaster, merely a symptom of the larger ongoing disaster we've been ignoring for decades that has suddenly erupted into public view.
Our historic and continuing reliance on fossil energy is creating a stream of waste -- in the air, on the land and in the water -- that is already drowning us in our own filth.
See Also
Dam Breach in Tennessee Releases Tsunami of Toxic Coal Sludge
Clean Coal, Clean Tar: Media Not Swallowing It Anymore
Alberta Tar Sands to Poison U.S. Great Lakes Region, Too
Canada's Tar Sands, America's Problem
Tar Sands: If You Have Tears, Prepare To Shed Them Now
Buffet and Soros Placing Fossil Bets
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Oilsands Tailings
I worked in a government lab studying oilsands tailings. (and I probably shouldn't be posting this but I really don't care anymore) Of particular concern are the older tailings furthest away from the outlet where the finest clay slowly settles. These are known as mature fine tailings, (MFT). Just to give you an idea of what this stuff is like. It has the consistency of thick paint, grey in colour and a slightly anoxic plus hydrocarbon smell. (Think of lighter fluid and soil you just dug up from a bog) It has a pH around 10 (think oven cleaner) and is streaked with little streamers of black goo. If you take a glass rod and pass it through this stuff it sticks to it like you would expect paint to coat a stir-stick. Upon rinsing the the tailings off the rod with clean water you are left bits of brown hydrocarbon residue stuck to the rod.
One of the main challenges in dealing with this stuff is that it gums up any equipment you use to process it. Whenever there is a system upset, (the plant burps) you endup with tailings that are even harder to deal with. We estimated that if left alone it would take centuries for this stuff to even settle. The mixture of colloidially dispersed clays and residual heavy hydrocarbon in water makes these tailings uniquely difficult to deal with.
Ironically enough, acid rain would be a welcome addition to these tailings since acid causes them to precipitate and settle in a timely manner.
Nonetheless the original plan deal with this stuff was that they would take advantage of the slightly higher density of tailings over fresh water, build up the dikes a good 10ft higher, "cap" with fresh water and everyone would be awe at the creation of an artificial lake. Which must have sounded great to the legislators during the 60s and 70s who had no idea of the concept annual inversions in lakes, or that these dikes might leak.
So the companies went ahead with their scheme with the idea that dealing with these tailings would be trivial and cost pennies per cubic meter. Now that the ludicrousness of this scheme has been exposed, these companies are basically expecting the government to grandfather them from new environmental policies that would have them properly treat their water. A process costing at dollars to tens of dollars per cubic meter , that would effectively make oilsands development uneconomical. So now, they are now arguing that they should only have to pay the pennies per cubic meter they were originally wiling to pay to cap these ponds with fresh water and that the government (and therefore the taxpayers) should pay the additional cost of properly treating the tailings, since they came up with the new standards after they started.
So essentially the process is deadlocked in courts, and legislatures, meanwhile, new oilsands projects are being proposes and approved with minimal public input or environmental assessment.
So yeah that is my take on Oilsands.
Mea Culpa
A friend told me she was offended by the statement I made that the ash spill in Tennessee is "not the real disaster." My apologies. I did a poor job of making the point that in order to really repair Tennessee, we have to do more than clean up the horrible spill.
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