DIRTY OIL- THE ATHABASCA TAR SANDS

Years ago as a boy summering in rural Smithtown, I recall pleasantly our country road, which was then just a natural glacial, yellowish, Long Island sand. My friends and I happily walked barefoot all summer long on the sandy byways we called “dirt roads”. But when I was about ten or eleven, the Town of Smithtown began “oiling" the roads. One day they arrived at our isolated place with with big trucks and a smelly tar-spreader to end our barefoot ways. They raked over the ridged and wash-board-rumpled sand and when smooth and level, they simply sprayed a thick layer of black oil over the dry sand. The oil soaked in and coated the grains. A thin layer of more sand was spread on top. The result was a smelly, tarry mess for a good week. But soon the volatiles in the oil dispersed into the air and the tarry surfaces hardened.

In our days, that tarry stuff is most likely man-made, the waste product of the distialation process, but it also occurs naturally, as tar-seeps such as the famous La Brea Tarp Pits in California. But perhaps one of the earliest exploited tar pits in the western world, are pits found on the western Greek island of Zante, (aka Zakynthos). The pits are located on the south end of Zakynthos near the little village of Keri. It is about ten miles from the port city of Zakynthos. I visted the Keri tar pits with my archeo-geology students in the late 1990s. We all hired motor skooters for the trip over winding country roads to a spot near the sea where tar seeped out of the ground. We collected a few samples and gathered there to retell the tales of how the ancient Athenians exploited this very seep to calk the bottoms of their ships...the ships that eventually saved the western world from being over-run by the Persians, when they helped defeat the the Persian navy under King Xerxes at the battle of Salamis in 480 BC. The Keri tar is fluid enough to flow readily in the spring temperatures on Zante. But other deposits of petroleum which remain buried close to the surface or exposed to heat underground (perhaps from intrusive igneous deposits) may loose their volatile components and turn into a black, viscous, natural tar, like that on our roads. Like asphalt roads, they too are mixed with coarse sand. These oiled-sands are essentially the same as what we find occuring naturally in the now famous exposures of the Canadian and Venesuelan tar sands. The tar sands deposits, similar in appearance to the stuff that first covered our early Long Island dirt roads, is now being considered--after the more-easily recovered and cleaner burning "sweet crude" has been exploited--as a source of difficult to extract but avaialable oil to meet the world's unquenchable thirst for petroleum.

Though the historians and archaeologists may not agree with us, we can campartmentalize human history into periods or "ages" based on the predominant fuel or source of energy. Today, since the middle of the last century (and the close of the “Coal Age”) we live in what we may call the “Petroleum Age”. Whether we are always aware of it or not, petroleum surrounds us, it colors our walls, fires our home furnaces, fuels our transportation vehicles and, as well, perhaps most importatantly, petroleum-derived fertilizers nourish our crops and aid in food production. Each morning we dress ourselves in synthetic fabrics produced from petroleum, then (almost) all of us drive to work in autos powered by gasoline an oil derivitive. Our vehicles roll along on sysnthetic rubber tires made from petroleum, on roads surfaced with a bitumen which is the end, waste-product of the fractional distillation which produces the gasoline, diesel oil, motor oils and many other of our industrial products. The thick gooey stuff we call “tar” that ends up in the bottom of the of the oil distillery after the gasoline, heating oil and diesel are vaporized off is used to coat roofs, spread on asphalt driveways, and used too as a general sealant. The vast majority of the tarry black stuff is what is mixed with sand and gravel and spread down on our roads to provide the smooth surface upon which we find driving so pleasant. But lets return to what is happening today in western Canada where large deposits of a similar substance (to our modern day road surface) is found just beneath the soggy soil and muskeg in the northern spruce and hemlock forest zone.

The dark bituminous substance that occurs in western Alberta in Canada was well-known to the Cree and Athabascan native-Americans of that region in prehistory. The Cree, like the Athenians, used the black sticky substance to waterproof their birch-bark canoes.

In the late 19th century, Canadian geologists mapped the extensive tar sand beds in western Alberta just below the surface of an area the size of Lake Superior or the US State of South Carolina (or about 30,000 square miles)in areas of forest, river valleys and muskeg terraine. The Economist (http://www.economist.com/node/17959688) reports that in that large zone there may be up to 173 billion barrels of recoverable hydrocarbon oil-equivalent. If that amount is verified it may have a value of some $16trillion dollars at modern day prices. And may support the US seemingly unquenchable thirst for oil (at 19 million bbls per day or 7 billion barrels a year) for some (173/7 = 24) twenty four years.

Late in the 20th century, about 1967 these deposits, which are easy to find with a simple earth probe, so there is no expensive and unpredictable drilling necessary, began to be exploited for their oil content. Several Canadian companies bought up virgin forest land, and by means of massive earth-moving equipment removed ten or fifty feet of muck, clay, and sand overburden, pumped out the ground and surface waters which seeped back into the excavation into a near-by large lake and removed the underlying layer of sand, rich in bitumen or tar. These operators transported the tarry sands to a near-by facility where the petroleum component was separated from the sand using lighter hydrocarbons (such as gasoline or kerosene) and large volumes of fresh water taken from the near-by pristine rivers. One serious problem is with the fresh water used to separate and extract the oil substance. It is estimated that the extraction and separation process requires between two (2) to five (5)barrels of water for each barrel of “oil” produced. At the present time with only a small percent of the massive resource exploited, existing operations use as much fresh water from the Athabasca River as does the entire city of Calgary, Alberta, which uses the river as it fresh water supply.

The mixture of water, tar-sands, and solvent is agitated to dissolve the “bitumen” into the solvent. The frothy mix is then separated from the sand and other solids which are dumped into the waste pond and the now dissolved bitumen is barreled and moved off site to an conversion plant where it was treated like a heavy oil. In more recent times, the diluted bitumen is mixed with liquefied natural gas to produce a more fluid, less viscous mix, termed “dilbit” which can be piped to refineries. The disadvantage is that this substance is particularly noxious were it to spill .

There are many problems with this enterprise. The extractive process is another form of open pit mining similar to what is used to extract coal from coal beds in Virginia, West Virginia, and Pennsylvania. The overburden is removed and dumped as spoil, in our eastern USA the coal seams are extracted and the land pushed back in a generally vain attempt to reconstruct the original natural surface. But in Alberta the soil is a mud and the land is marshy and wet. Water, soaks the deposit and dissolves the toxic substances which are a part of the bitumen fraction and is carried away into the near-by river system. These waste waters are pumped into “tailings ponds”, the waters of which become toxic to all forms of life---particularly migratory wildfowl which in their annual passage attempt to alight in these waters and must be constantly driven off. (recent reports document thousands of migratory wildfowl dying in these ponds) Other dissolved materials enter the river Athabasca River system and pollute it locally and downstream from the mine area. Air pollution is a consequence of the separation process as the solvents used are volatile and can and do pollute the atmosphere. There is no evidence that the disturbed landscape can be returned to function either as farmland (which it was not suited for prior to mining) or to forestry or functioning wildlife habitat. Secondly, this is just another way (but a more messy way) to exploit buried carbon and add it (and the sulfur and other minerals it contains) into the atmosphere as pollutants and greenhouse gases. Furthermore, since it takes a great deal of energy to separate the bitumen from the sand and then dissolve the “thick petroleum” fraction into a solvent to create a liquid form---both the mining and extractive process uses up a great deal more energy than lighter “sweet crude” oils which are extracted by drilling. It is estimated that the extraction, processing and burning of tar-sands-derived-oil generates somewhere between 10% and 45%more greenhouse gases than normal oil drilled from wells (http://www.scientificamerican.com/article.cfm?id=coming-to-america-tar-sands-from-canada).

The advantages from the oil developer point of view is that the resource is in a “safe” country, not likely to be attacked by insurgents or to be nationalized by a new and unfriendly government, and too it is close to the US market and refining facilities.
Some have referred to it as the only “free” world oil outside of the 70% of the world’s oil reserves of the OPEC nations.

Finally, one major problem is that Canada is planning to build a pipe line to its southern boundary the Keystone XL pipeline to carry “dilbit” to specialized plants in the USA. It represents another dangerous and potentially messy operation which like the Gulf oil spill can create a toxic, disaster over the areas it traverses. We have cause to worry.