Response to Heavy, Non-Floating Oil Spilled in a Great Lakes River Environment: A Multiple-Lines-Of-Evidence Approach for Submerged Oil Assessment and Recovery

Abstract

The Enbridge Line 6B pipeline release of diluted bitumen into the Kalamazoo River downstream of Marshall, MI in July 2010 is one of the largest freshwater oil spills in North American history. The unprecedented scale of impact and massive quantity of oil released required the development and implementation of new approaches for detection and recovery. At the onset of cleanup, conventional recovery techniques were employed for the initially floating oil and were successful. However, volatilization of the lighter diluent, along with mixing of the oil with sediment during flooded, turbulent river conditions caused the oil to sink and collect in natural deposition areas in the river. For more than three years after the spill, recovery of submerged oil has remained the predominant operational focus of the response. The recovery complexities for submerged oil mixed with sediment in depositional areas and long-term oil sheening along approximately 38 miles of the Kalamazoo River led to the development of a multiple-lines-of-evidence approach comprising six major components: geomorphic mapping, field assessments of submerged oil (poling), systematic tracking and mapping of oil sheen, hydrodynamic and sediment transport modeling, forensic oil chemistry, and net environmental benefit analysis. The Federal On-Scene Coordinator (FOSC) considered this information in determining the appropriate course of action for each impacted segment of the river. New sources of heavy crude oils like diluted bitumen and increasing transportation of those oils require changes in the way emergency personnel respond to oil spills in the Great Lakes and other freshwater ecosystems. Strategies to recover heavy oils must consider that the oils may suspend or sink in the water column, mix with fine-grained sediment, and accumulate in depositional areas. Early understanding of the potential fate and behavior of diluted bitumen spills when combined with timely, strong conventional recovery methods can significantly influence response success.

Physical properties of oil-particle aggregate (OPA)-containing sediments

“…The formation of OPAs has been documented from numerous oil spills in a variety of environments. These include the Enbridge incident, which in 2010 released of over than 3.2 million liters of diluted bitumen in the freshwater Kalamazoo River, where OPAs were deposited along channel margins, backwaters, and oxbows (Dollhopf et al, 2014. OPAs were also observed during the Baffin Island Oil Spill Project conducted in the early 1980s and the 1989 Exxon Valdez oil spill incident (Bragg and Owens, 1994;Bragg and Yang, 1995).…”

Physical and Chemical Connectivity of Streams and Riparian Wetlands to Downstream Waters: A Synthesis

“…; Dollhopf et al. ). Because of the widespread nature of streams and wetlands and their hydrologic connectivity, many contaminant spills are transferred to downstream waters if they are not rapidly contained.…”

“…Headwater streams impacted by past mining and smelting activities have been demonstrated to be sources of metal contaminants bound to river sediments hundreds of kilometers downstream (e.g., Hornberger et al 2009). Chemical spills entering fluvial hydrosystems are among the most publicly recognized disasters and can pose immediate and long-term human health and environmental impacts (e.g., Ruhl et al 2010;Dollhopf et al 2014). Because of the widespread nature of streams and wetlands and their hydrologic connectivity, many contaminant spills are transferred to downstream waters if they are not rapidly contained.…”

Diluted Bitumen: Physicochemical Properties, Weathering Processes, Emergency Response, and Recovery

“…The growing volume of diluted bitumen transportation has led to an increasing potential for spills. For instance, the pipeline operated by Kinder Morgan released about 224 m 3 of diluted bitumen into the Burrard Inlet, British Columbia, Canada, in 2007(Environment Canada, 2013; the Enbridge Line 6B pipeline leaked about 3,320-3,790 m 3 of diluted bitumen into the Kalamazoo River in July 2010 (Dollhopf et al, 2014;Swarthout et al, 2016); the Enbridge's Athabasca pipeline released about 230 m 3 of diluted bitumen into the Red Deer River on 18 June 2012 (Brown, 2012). Accurate prediction of the spilled diluted bitumen's transport and behavior is of importance to local authorities and oil companies for quick and efficient response to diluted bitumen spills.…”