For the pipeline project represented in the August 2011 final EIS, approximately 95% of the land
affected by pipeline construction and operation was privately owned, with the remaining 5%
almost equally state and federal land. Private land uses were primarily agricultural—farmers and
The pipeline’s construction and continued operation would involve a 50-foot-wide permanent
right-of-way along the length of the pipeline. Keystone agreed to compensate landowners for
losses on a case-by-case basis. However, a concern among landowners and communities along
the route is the potential for their land or water (used for drinking, irrigation, or recreation) to be
contaminated by an accidental release (spill) of oil. That concern is heightened in areas where the
pipeline will be located near or would cross water or is in a remote location.
A primary environmental concern of any oil pipeline is the risk of a spill. In estimating the
possible impacts of an oil spill, location is generally considered the most important factor—
particularly the potential for the spill to reach surface or groundwater. For example, the potential
impacts of a spill to water is highlighted in the Keystone XL final EIS, as follows:
The greatest concern would be a spill in environmentally sensitive areas, such as wetlands,
flowing streams and rivers, shallow groundwater areas, areas near water intakes for drinking
water or for commercial/industrial uses, and areas with populations of sensitive wildlife or
A release of oil on land would not necessarily result in surface or groundwater contamination.
The potential for a spill to reach water would depend on factors such its proximity to a water
source (e.g., on or near a creek or stream or located on land where the groundwater table is close
to the surface) and the characteristics of the environment into which the crude oil is released (e.g.,
porous underlying soils), and the volume of the spill, the duration of the release, and the viscosity
and density of the crude oil.
The size of potential spills and the type of oil that would likely be released from the Keystone XL
pipeline have been issues of concern to opponents of the project. In its July 16, 2010, comments
on the draft EIS for the Keystone XL pipeline, EPA expressed particular concern over the
potential adverse impacts to surface and ground water from pipeline leaks or spills. That concern
stemmed from two areas—the toxicity of chemical diluents that may be used to allow bitumen to
be transported by pipeline and the lack of risk assessment for potential “serious or significant
spills,” including an evaluation of spill response procedures in the wake of such a spill.
Concerns reflected in EPA’s letter were realized 10 days later when the Enbridge Energy Partners’
Alberta Pipeline ruptured near Marshall, MI. The resulting spill released dilbit crude into a
tributary creek of the Kalamazoo River and traveled approximately 40 miles downstream in the
Kalamazoo River. Initially estimated by Enbridge as a release of approximately 800,000 gallons
of crude, EPA subsequently estimated that over 1.1 million gallons were released. The spill
resulted in over 220 areas of moderate-to-heavy contamination, including over 200 acres of
submerged oil on the river bottom and over 300 solidified oil deposits.119 Enbridge estimates that
cleanup will cost approximately $700 million.
The Enbridge spill highlighted several issues of concern among environmental groups and
communities along the pipeline route—in particular, the nature of the dilbit crude likely carried
by the Keystone XL pipeline. The dilbit crude in the Enbridge spill had been diluted with benzene
and other hazardous constituents. Following the spill, high levels of benzene in the air prompted
the issuance of voluntary evacuation of residents in the area. Concern over the presence of
similarly toxic constituents, particularly the degree to which the level of toxic constituents may be
unknown at the time of a release, has been an ongoing concern among environmental and
The Enbridge spill was considered a “very large spill” and not necessarily one that would likely
occur along the Keystone XL pipeline route. However, in its first year of operation,
TransCanada’s Keystone pipeline experienced 14 spills. Although mostly minor spills, one spill at
the Ludden, ND, pump station resulted in the release of 21,000 gallons of oil. Like the Enbridge
release, that release was first reported by local citizens, not as a result of the Keystone’s release
detection equipment. These incidents have made pipeline opponents concerned that, absent a
witness to a spill, a leak in a remote area could potentially go undetected for a long period.
Also as illustrated in the aftermath of the Enbridge spill, cleanup of bitumen crude presents
certain challenges. Dilbit is a relatively heavy crude oil mixture compared to other crude oils. In
general, heavier oils are more persistent and present greater technical challenges in removal after
a spill compared to lighter oils. Almost two years after the Enbridge spill, cleanup efforts
continue. Since the spill, public access to 39 miles of the river system was banned to protect
public health and safety. The first three-mile segment of river reopened to the public on April 27,
2012. Elements of the cleanup are expected to last until 2015.
Regardless of design, construction, and safety measures, the Keystone XL pipeline will likely
have some number of spills over the course of its operating life. The unique oil spill response
efforts necessary for dilbit crude make an accurate assessment of potential oil spill risk
particularly relevant when addressing concerns expressed by opponents to the Keystone XL
pipeline. The need for more conclusive analysis of potential risks associated with the transport of
dilbit crude was addressed, in part, in the Pipeline Safety, Regulatory Certainty, and Job Creation
Act of 2011 (P.L. 112-90, enacted January 16, 2012). In particular, under Section 16, “Study of
transportation of diluted bitumen,” the Secretary of Transportation is required to conduct an
analysis to determine whether there is any increased risk of a release for pipeline facilities
transporting diluted bitumen. In response to that directive, the PHMSA contracted with the
National Academy of Sciences to conduct a full and independent study of this topic, which is not
yet completed. For further analysis of environmental issues associated with the Keystone XL
project, see CRS Report R42611, Oil Sands and the Keystone XL Pipeline: Background and
Selected Environmental Issues, coordinated by Jonathan L. Ramseur.
Update, 5:15PM Pacific: In response to Steven Kopits characterization of Enbridge, please see “Enbridge Resisting Final Clean-Up of Its Michigan Oil Spill,”:
In October, the U.S. Environmental Protection Agency asked Enbridge Inc., the pipeline’s Canadian owner, to clean up several miles of the river where submerged oil is still accumulating. The proposed order told Enbridge to dredge 80 to 100 acres of the riverbed. The request was based on the results of a yearlong study the EPA conducted with oil cleanup experts, Michigan state regulators and a committee of about 15 scientists.
The dredging is needed, the agency said, because the oil could spread into uncontaminated areas of the river if it isn’t removed.
Steve Hamilton, a Michigan State University professor and a scientist on the committee, said the number of acres could change as the EPA continues to study the situation. “No specifics have been decided…Further recovery actions in the most contaminated sediments—potentially including dredging—are being contemplated.”
Enbridge responded to the request by asking the EPA to delay issuing its final order until the agency completes some ongoing scientific studies. In a Nov. 2 letter obtained by InsideClimate News, the company questioned the EPA’s assertion that the submerged oil is “mobile” and could contaminate sections of the river that are already clean.
And from National Journal:
You may remember Enbridge from the costliest onshore oil spill in U.S. history, caused by a corroded Michigan pipe that leaked more than 800,000 gallons of Canadian oil in 2010. The National Transportation Safety Board found that 81 percent of that oil gushed after Enbridge employees misread alarms along their purportedly state-of-the-art system and twice tried to restart the pipeline.