A study released on June 11 suggests that the worst-case spill scenarios contemplated by TransCanada, the company behind a proposed 2,000-mile pipeline linking oil deposits in Canada to the American Gulf Coast, are grossly underestimated - and that hundreds of rivers, streams and aquifers are vulnerable to toxic oil contamination.
The analysis, conducted by a professor of civil engineering at the University of Nebraska-Lincoln at the request of the environmental group Friends of the Earth, examined methods used by TransCanada to calculate spill scenarios for an existing leg of the pipeline system, known as Keystone, and determined that the company made "flawed and inappropriate assumptions about the frequency and severity of expected spills from its pipelines."
Among other things, the analysis concludes that while TransCanada has estimated that the proposed Keystone XL expansion pipeline would experience 11 significant spills of more than 50 barrels, or 2,100 gallons, of crude oil over a 50-year lifespan, "a more realistic assessment is 91 significant spills."
The analysis also suggests that TransCanada tweaked its spill factor calculations to produce an estimate of one major spill on the 1,673 miles of pipeline about every five years. But an examination of government data on spill rates for similar pipelines, according to the study, suggests that Keystone would experience "a more likely average of almost two major spills per year."
In just one year of operation, the existing leg of the pipeline has had one significant spill and 11 smaller spills.
The study also concluded that the amount of time it would take to shut down the proposed pipeline should a leak occur at or near a river crossing - among the most environmentally sensitive points along any pipeline - could be as much as 10 times greater than that assumed by TransCanada.
Keystone XL would cross nearly 2,000 rivers in six states.
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