It's Time to Take Action on the Tar Sands: NAS Study on Diluted Bitumen Spills From Pipelines Confirms the Need for Stricter Oversight

Following two major spills of tar sands oil (in the form of diluted bitumen) in 2010 and 2013, it became clear that years of warnings from scientists and the environmental community about the dangers of transporting this thick, toxic substance were significant and poorly understood. Indeed, NRDC raised many of these issues in a 2011 report on tar sands pipeline safety hazards, which highlighted a number of risks posed by tar sands transported as diluted bitumen and called for new regulations aimed at addressing these risks. Now, the National Academy of Sciences has released a report examining the environmental fate of the most common form of tar sands oil--diluted bitumen--when it is spilled from pipelines. In the NAS' latest report, researchers confirmed that diluted bitumen from Alberta's tar sands differs substantially from other types of oil commonly moved by pipeline across the U.S. These differences can lead to extremely difficult spill response situations where oil that initially floated begins to submerge and finally sink after only a brief period of weathering. On top of this, the NAS also found that our first responders and the various local, state, and federal agencies that respond to oil spills are poorly equipped to deal with spills of diluted bitumen. In light of this lack of preparedness, the NAS called on key agencies--from the Pipeline and Hazardous Materials Safety Agency (PHMSA) to the Environmental Protection Agency (EPA)--to implement a number of significant changes to their spill response regulations in order to address the unique threats and challenges posed by tar sands oil being moved as diluted bitumen.

Mayflower Spill.jpgOil and water mixing following the Mayflower, Arkansas spill. Photo by Rocky Kistner, NRDC.

A number of key findings from the NAS report deserve direct highlighting. These points validate years of work by scientists and the environmental community calling on decision-makers to acknowledge the threats and challenges tar sands oil poses to our water supplies, communities, and first responders. What follows is a list of key findings from the NAS report:

  • "In comparison to other commonly transported crude oils, many of the chemical and physical properties of diluted bitumen, especially those relevant to environmental impacts, are found to differ substantially from those of the other crude oils. The key differences are in the exceptionally high density, viscosity, and adhesion properties of the bitumen component of the diluted bitumen that dictate environmental behavior as the crude oil is subjected to weathering (a term that refers to physical and chemical changes of spilled oil).
  • "Spills of diluted bitumen into a body of water initially float and spread while evaporation of volatile compounds may present health and explosion hazards, as occurs with nearly all crude oils. It is the subsequent weathering effects, unique to diluted bitumen, that merit special response strategies and tactics . . . In cases where traditional removal or containment techniques are not immediately successful, the possibility of submerged and sunken oil increases. This situation is highly problematic for spill response because 1) there are few effective techniques for detection, containment, and recovery of oil that is submerged in the water column, and 2) available techniques for responding to oil that has sunken to the bottom have variable effectiveness depending on the spill conditions.
  • "The majority of the properties and outcomes that differ from commonly transported crudes are associated not with freshly spilled diluted bitumen, but with the weathering products that form within days after a spill. Given these greater levels of concern for weathered diluted bitumen, spills of diluted bitumen should elicit unique, immediate actions in response.
  • "Broadly, regulations and agency practices do not take the unique properties of diluted bitumen into account, nor do they encourage effective planning for spills of diluted bitumen.
  • "In light of the aforementioned analysis, comparisons, and review of the regulations, it is clear that the differences in the chemical and physical properties relevant to environmental impact warrant modifications to the regulations governing diluted bitumen spill response plans, preparedness, and cleanup."

In recent years, many of America's worst oil spills have involved tar sands oil. In 2010, more than 800,000 gallons of tar sands oil was spilled into the Kalamazoo River in Michigan, resulting in immediate negative health impacts for nearby residents, sunken oil, and an ongoing remediation effort that continues to locate sunken oil more than five years later. All told, the cost of cleanup has exceeded $1 billion and long term contamination of the river is expected due to the difficulty of removing the sunken bitumen and the fact that it does not quickly decompose.

In 2013, another tar sands oil spill--this time as much as 300,000 gallons--overflowed the streets and homes in the town of Mayflower, Arkansas, leading to evacuations and contamination so persistent that many homes nearby were later condemned. Many of the same challenges and impacts facing emergency responders in Michigan were also encountered following the Mayflower spill.

Kalamazoo Spill.jpgWarnings following a tar sands diluted bitumen spill that reached the Kalamazoo River in Michigan. Photo courtesy of Jason Lacey.

These spills, and the public debate over pipelines like the formerly proposed Keystone XL tar sands pipeline, have raised significant public concern over the transportation of tar sands oil. Indeed, key federal agencies like the U.S. EPA and U.S. Coast Guard have both expressed concern about the influx of new and highly unique forms of oil into the U.S. and the critical need for a better understanding of the properties of these oils and their behavior in a variety of spill scenarios. Acknowledging these concerns, today's study puts forward a number of recommendations aimed at improving our preparedness in the case of future spills of tar sands diluted bitumen spills. Among the recommendations are calls for PHMSA, EPA, and the U.S. Coast Guard to make serious and significant changes to their current regulations governing crude oil pipelines and oil spill response and preparedness.

With today's study, the debate over the risks transporting tar sands should turn to how we can make sure that the environmental tragedies of the Kalamazoo River and Mayflower, Arkansas do not happen again. For this reason, NRDC and many other environmental organizations, communities, and leaders at all levels of government continue to call for federal decision-makers to write and implement regulations governing the transportation of extra-heavy oil like diluted bitumen from the Alberta tar sands. And while the NAS focused their attention on spills from pipelines in this latest report, researchers made clear that their findings were broadly applicable to a number of other modes of oil transport. These include railcars, barges, tankers, and trucks. Thus, it is time that regulators acknowledge the pressing need to address the threats that tar sands oil pose to all forms of oil transportation infrastructure, so much of which is built beside our nation's critical water bodies and adjacent to sensitive communities.

About the Authors

Josh Axelrod

Policy Analyst, Canada Project, International program

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