(Reuters) - Replacing the Keystone XL pipeline with oil-laden freight trains from Canada may result in an average of six additional rail-related deaths per year, according to a U.S. State Department report that is adding to pressure for President Barack Obama to approve the line.
The long-awaited study, released on Friday, focused on the environmental impact of TransCanada's $5.4 billion pipeline, but also spent several pages analyzing the potential human impact of various ways to transport oil, using historical injury and fatality statistics for railways and oil pipelines.
Although it excluded the runaway oil train derailment that killed 47 people in Lac Megantic, Quebec, last summer, the tragedy that first shone a critical light on the rapidly expanding trend in shipping crude by rail, the findings highlight the risks or railway transport versus pipes.
Shipping another 830,000 barrels per day (bpd) of crude "would result in an estimated 49 additional injuries and six additional fatalities for the No Action rail scenarios compared to one additional injury and no fatalities" per year if Keystone XL is built, according to the report.
Keystone XL would carry 830,000 bpd from Alberta's oil sands U.S. refiners, but has been awaiting a presidential permit for more than five years. The "No Action" options refer to the likely alternative outcomes if Obama rejects the permit or the project is not built for some other reason.
The Association of American Railroads suggested that the report had painted an unfair comparison.
"Unfortunately, the (report) factored in casualties that are predominantly those of trespassers on railroad rights of way, unrelated to the hazardous commodities being transported, while limiting pipeline casualties to those who are killed or injured in hazardous liquid spill incidents," AAR President and CEO Edward R. Hamberger said in a statement.
"We believe both rail and pipelines are safe and play an important role in our energy economy."
The report also showed that carrying crude by rail, instead of by pipeline, was likely to result in a higher number of oil spills and a larger amount of leakage over time.
If Keystone XL is built as planned, according to the study, it would likely spill an average of just over 500 barrels per year, with a leak occurring once every two years. Under the most optimistic scenario involving rail, however, nearly 300 spills would occur per year, with over 1,200 barrels released in total, according to estimates provided in the report.
The State Department study made no specific recommendation, but in broad terms suggested that Keystone was unlikely to have much impact on climate change, as oil trains would be used instead to carry growing Canadian production to market.
That finding cheered proponents, who said it left Obama with few reasons not to approve the pipeline, and frustrated environmentalists who argue that rejecting it would help stymie energy-intensive oil sands production and processing.
The State Department's estimate on the potential human toll of relying more heavily on oil-trains may not only add to calls for Obama to grant the Keystone permit, but may also play into the lobbying battle between the rail and pipeline industries, both of which argue they are safe and environmentally sound.
Kerri-Ann Jones, Assistant Secretary of State in charge of environmental affairs, told reporters on a conference call on Friday that the study examined the environmental and safety impacts of shipping oil by rail rather than pipeline, but declined to elaborate on the findings.
"I would refer you to the document because it depends on a number of things," she said. "What the document does is lay out all of the different variables. It doesn't really step forward and say which way to go. It's presented as information for the decision-maker in the next step."
A State Department official reached on Sunday also declined comment. Obama is not expected to make a final decision before the summer.
The fatality and injury estimates were based on data from both the Federal Railroad Administration (FRA) and the Pipeline and Hazardous Material Safety Administration, the report said.
However, since crude oil transport was relatively rare until recently, the analysis was expanded in both cases to include data covering all types of material carried by Class I railways, as well as all pipeline incidents that involve liquid petroleum products, which includes refined fuels.
It showed that 16,946 injuries and 2,228 fatalities were reported for all materials transported by Class I railroads between 2002 and 2012, with a large share involving trespassers on rail lines. It also said the data showed that incidents fell sharply in 2004 and had continued to decline.
The report found that 46 injuries and 19 fatalities were reported for all hazardous liquids transported by pipeline.
(Reporting by Jonathan Leff and Roberta Rampton in Washington; Editing by Joseph Radford)