Regarding the article ``Canada Is Ready to Exploit Huge Oil Reserves Locked in Sands,'' Oct. 21:
I believe the two present projects (500 miles north of Edmonton) produce approximately 170,000 barrels per day rather than 300,000. The cost of $15 per barrel is likely Canadian dollars, meaning US$10 rather than US$20. The ``new'' extraction technique of pumping pressurized steam into the ground to fluidize oil is not really new. It has been used in a number of countries for some time. Venezuela does it almost as a matter of fact once their pumping oil fields start to be depleted; the addition of steam in much the same way as the author describes increases the output by anywhere from 20 percent to 40 percent.
The only major difference is the great depth he describes. This may be due to the depth at which the oil is located and may also be related to the cold in the far north. The current operating tar sands projects have found that the oil is in quite shallow layers, often no more that 100 feet deep. William D. Tanner, Largo, Fla. Former VP/Engineering, Foster Wheeler Ltd., Canada
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