#KeystoneXL Just how dirty are Tar Sands?

Through the '70s after one oil crisis after another there was a proliferation of maps showing the existence of oil deposits throughout the world.

The rural regions of Canada had huge deposits, but they were marked as useless sludge not any better than the goop in the La Brea Tar Pits. Nobody wanted that oil. Why should they? It is the ultimate waste product, oil so old it has gone to dust.

But not so fast, the black gold there became cost effective after oil prices spiked and stayed there.

Natural bitumen (often called tar sands or oil sands) and heavy oil differ from light oils by their high viscosity (resistance to flow) at reservoir temperatures, high density (low API gravity), and significant contents of nitrogen, oxygen, and sulfur compounds and heavy-metal contaminants. They resemble the residuum from the refining of light oil. Most heavy oil is found at the margins of geologic basins and is thought to be the residue of formerly light oil that has lost its light-molecular-weight components through degradation by bacteria, water-washing, and evaporation.

Extracting this "resource" is expensive since the soil is basically strip mined and heat processed. Making the actual extraction of this oil the most inefficient method of oil extraction known.

Tar Sands Extraction and Processing

Tar sands deposits near the surface can be recovered by open pit mining techniques. New methods introduced in the 1990s considerably improved the efficiency of tar sands mining, thus reducing the cost. These systems use large hydraulic and electrically powered shovels to dig up tar sands and load them into enormous trucks that can carry up to 320 tons of tar sands per load.

With tires that weigh more than your fully loaded SUV the equipment to extract this oil increases the carbon footprint of this oil dramatically. Only 10% of the material extracted is useable as oil.

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After mining, the tar sands are transported to an extraction plant, where a hot water process separates the bitumen from sand, water, and minerals. The separation takes place in separation cells. Hot water is added to the sand, and the resulting slurry is piped to the extraction plant where it is agitated. The combination of hot water and agitation releases bitumen from the oil sand, and causes tiny air bubbles to attach to the bitumen droplets, that float to the top of the separation vessel, where the bitumen can be skimmed off. Further processing removes residual water and solids. The bitumen is then transported and eventually upgraded into synthetic crude oil.

About two tons of tar sands are required to produce one barrel of oil. Roughly 75% of the bitumen can be recovered from sand. After oil extraction, the spent sand and other materials are then returned to the mine, which is eventually reclaimed.

About that reclaiming. Apparently the miners did not get the memo. The toxic sand is the Koch Brothers' new White Elephant.

Until recently, the dusty piles rising above the Calumet and other waterways near Midwest refineries had been a largely unnoticed consequence of a shift to thicker, dirtier oil from Canada.

The growing black mountains first became an issue in Detroit, where another Koch company maintained a towering repository of petcoke from a nearby Marathon Petroleum refinery. In August, Mayor Dave Bing ordered it removed in response to community complaints.

Under pressure from [Chicago Mayor Rahm] Emanuel and Illinois Attorney General Lisa Madigan, Beemsterboer [a storage terminal owner] called in a giant Canadian freighter last week to take away all of its petcoke. A legal agreement expected to be filed Thursday in Cook County Circuit Court would block the company from accepting the refinery byproduct until it adopts more aggressive dust controls.

It is unclear where the petcoke goes after it is stored in Chicago.

Because this pet coke is highly toxic sludge basically returning it to the ground is likely to trigger innumerable environmental violations. So the cost of playing pet coke musical chairs must be added to the carbon footprint equation.