Stansbury is the author of numerous studies on water resources and hazardous waste management published in peer-reviewed journals. The full study with complete references is available at http://watercenter.unl.edu.
You can also see the study's summary of key findings at the Friends of the Earth website here.
The first paragraph of the summary, which is beyond ugly, begins:
A major spill from the proposed Keystone XL tar sands pipeline on the Platte River in Nebraska could spill 5.9 million gallons of toxic, corrosive tar sands oil and spread pollutants such as carcinogenic benzene in excess of federal health standards hundreds of miles downstream, contaminating drinking water for hundreds of thousands of people as far south as Kansas City, Mo. Even a small, undetected leak from an underground rupture of the pipeline in the Nebraska Sandhills could pollute almost 5 billion gallons of groundwater with benzene at concentrations exceeding safe drinking water levels – enough water to form a plume 15 miles long, posing serious health threats to anyone using the underlying Ogallala Aquifer for drinking water or agriculture. And a worst-case spill at the pipeline’s crossing of the Missouri or Yellowstone Rivers in Montana could spill well over 5 million gallons of tar sands oil, contaminating drinking and recreational water in North Dakota with harmful levels of benzene and other chemicals.
Not to be missed is the study's examination of TransCanada's outrageous attempt to minimize the risks of its project.
TransCanada’s Flawed Assumptions
According to TransCanada, significant spills (more than 50 barrels) are expected to be very rare (0.00013 spills/year/mile, or 11 major spills over a 50-year design life). However, TransCanada made several highly questionable assumptions, including:
Therefore, a more realistic assessment of expected frequency of significant spills, based on historical data, is 0.00109 spills per year per mile, resulting in 91 significant spills over a 50-year design life of the pipeline (including more than 12 spills from holes greater than 10 inches).
- TransCanada ignored historical data on almost one-fourth of pipeline spills by excluding all spills for which the cause is not known.
- TransCanada assumed, without supporting data, that Keystone XL will be constructed so well that it will have only half as many spills as existing pipelines, even though the tar sands crude to be transported through the pipeline is more likely to leak than the conventional crude in other pipelines.
TransCanada consistently states the frequency of spills in terms of spills per year per mile. This is misleading; a more appropriate way to state the frequency would be the frequency of a spill somewhere along the length of the pipeline. Stating the spill frequency in terms of spills per mile is comparable to acknowledging that, although some 33,000 deaths from automobile accidents occur annually in the U.S., the average annual fatality rate across 350 million people is only 0.000094; therefore, fatalities from automobile accidents are so rare as to be unimportant.
TransCanada’s other major flawed assumption – again, unsupported by any data – is that in case of an accident, the Keystone XL can be shut down in 11.5 minutes. This is wildly optimistic. In the June 2010 spill on the very similar Enbridge pipeline in Michigan, the time to finally shut down the pipeline was approximately 12 hours, and during that time the pumps operated for at least two hours. Therefore, a more realistic estimate of shutdown time is two hours. When applied to a hypothetical spill at the Keystone’s pumping station in Hardisty, Alberta, the difference between TransCanada’s assumptions and the appropriate values is a spill of 41,504 barrels vs. one of 87,964 barrels.