by Dr. Steve Hamilton, Kalamazoo River Watershed Council
The July 2010 rupture of a major pipeline carrying tar sands crude oil across southern Michigan produced one of the worst oil spills in Midwest U.S. history, releasing about 20,000 barrels into the Kalamazoo River system. Within a few days over 30 miles of river were affected, and unseasonably high river levels carried the oil well into the floodplain and riparian zones.
Enbridge Energy Partners, the responsible party for the spill, was quickly joined by the U.S. EPA in a major effort to stop the downstream movement of the oil and to recover as much as possible. Fortunately the floating oil was effectively halted before it could reach the lower 80 miles of the river and Lake Michigan. Most of the oil has since been recovered, either from the water surface or on land near the spill site, but the impact of that which remains may be significant.
As the river fell the oil was deposited on foliage and soils. The cleanup of that oil involved hundreds of workers who entered on foot and manually removed contaminated vegetation. The clock was ticking for this work because after leaf fall in November it would have been much more difficult. Most of the contaminated foliage was removed in time. However work continues to surgically excavate or dredge hotspots where oil settled in soils or sediments. The long-term ecological impacts of exposure to the oil, as well as the aggressive cleanup that ensued, remain uncertain at this time.
The Kalamazoo River Watershed Council was involved as an assisting agency in the emergency response, providing local knowledge in an Environmental Advisory Group set up by the Incident Command. Most oil spills have occurred in marine waters or more industrialized settings, and we found that the cleanup guidelines had to be retailored to be effective in a relatively pristine floodplain river system.
A grant from Freshwater Future helped the Council to meet the many demands for outreach and education in regard to the spill. Board members and our single staff member have made presentations to diverse audiences and demand continues to be high. Examples include public presentations hosted by the Kalamazoo Nature Center, Michigan State University, the American Chemical Society, and the University of Michigan. We have also been invited to present on the event to several local K-12 schools, as well as the Girl Scouts.
While the situation that led to this disaster needs a lot of scrutiny to understand what went wrong, I think the emergency cleanup response led by EPA and Enbridge was as good as it could have been, and most of the oil has now been removed. I am concerned, however, that ongoing aggressive cleanup actions may be reaching the point of diminishing returns, and may do more harm than good.