In a draft report submitted this week to the State of Michigan, a team of experts evaluates the economic, environmental and cultural impacts of a “worst case scenario” spill or release from the Straits Pipelines.
Led by Michigan Technological University’s Guy Meadows, 41 researchers conducted an independent risk analysis of the two parallel, 20-inch pipelines that form the 4.5-mile section of Enbridge’s Line 5 that runs beneath the Straits of Mackinac. The draft report details nine different worst-case scenarios and outlines impacts for each.
"I am proud of the way in which our universities have come together to provide a fact based analysis of a very complex problem, under an extremely tight time frame,” Meadows said. “In conducting this work, we have also advanced knowledge about the fate and transport of oil in freshwater."
Meadows is the Robbins Professor of Sustainable Marine Engineering and director of the Great Lakes Research Center at Michigan Tech. The Agency for Energy (MAE), Attorney General’s Office (AG), Department of Environmental Quality (DEQ) and Department of Natural Resources (DNR) contracted with Michigan Tech for the risk analysis report.
The risk analysis team included 21 researchers from Michigan Tech and 20 from external organizations. Nine universities contributed to the analysis, seven of which are within the state of Michigan: Michigan Tech, the University of Michigan, Michigan State University, Wayne State University, Western Michigan University, Grand Valley State University and Oakland University. The two out-of-state universities are North Dakota State University and Loyola University Chicago.
When and How
In keeping with the scope of work published by the State, the researchers completed the following tasks:
- Identifying and analyzing the duration and magnitude of a “worst case” spill or release of oil or other products from the Straits Pipelines into the environment.
- Analyzing the likely environmental fate and transport of oil or other products released from the Straits Pipelines in a worst-case scenario.
- Analyzing how long it would take to contain and clean up the worst-case release.
- Analyzing the short- and long-term public health and safety impacts.
- Analyzing the short- and long-term ecological impacts.
- Analyzing potential measures to restore the affected natural resources and mitigate the ecological impacts.
- Estimating the amount of natural resource damages that would result from a worst-case release.
- Estimating the governmental costs that would be incurred as a result of a worst-case release.
- Estimating all other economic damages, public and private, that would result from a worst- case release.
Members of the team also assessed what the report calls broader impacts of a worst-case scenario spill to assess the perceived risks and concerns expressed by local communities, civil society groups, indigenous communities, governmental agencies and the public at large.
Because no oil spill as large as the scenarios analyzed in the report has ever occurred in the waters of the Great Lakes, researchers reviewed a selection of other events as analogs to evaluate the potential impacts of a Straits spill. They based their approach on an accumulation of worst-case assumptions that were consistent with the federal definition of “the largest foreseeable discharge of oil,” found in Title 40, section 194.5 of the Federal Code of Regulations, to determine the maximum possible volume that could be released.
By definition, the worst-case spill size is much larger than would be expected under average or typical conditions. According to the draft report, the impacts of a spill depend on when it occurs and how meteorological conditions disperse the oil. Researchers conducted a total of 4,380 oil dispersal simulations over a one-year period of meteorological, water current and ice cover conditions that are representative of seasonal conditions in the Straits. Previous hydrodynamic modeling capabilities for the Straits were updated in this assessment to include wind transport of oil, ice-cover conditions and potential effects on oil dispersal and evaporation.
The definition of a worst-case scenario also varies depending on which impacts are being assessed. For example, a winter spill would be the most difficult to respond to safely and effectively, while a spill that occurred in the spring would generate the highest economic costs. To represent this range, a total of nine scenarios were analyzed as potential worst cases for different tasks. The spring scenario is used as the representative scenario to estimate the overall liability from a worst-case scenario spill at the Straits because a spill at that time of year, just prior to the summer tourism season in the Straits, would have the largest impact overall.
The report also considers various modes of failure for the Straits Pipelines and separates these failures into five tiers. Under this model, discharge amounts range from 4,400 barrels of oil (bbl) to 58,000 bbl. Each bbl contains 42 U.S. gallons.
Next Steps
Now that the draft analysis has been submitted, the public will have 30 days to comment on the report. The risk analysis team will hold a public presentation on the draft report at 6pm on August 13, 2018, at the Boyne Highlands Convention Center in Harbor Springs, Michigan. When the public comment period closes, and after responding to public and State input on the draft, the team will prepare a final report to be delivered by September 15, 2018.
When the final report is issued, the State will require Enbridge Energy Limited Partners, which owns and operates Line 5, to maintain an adequate financial assurance mechanism to cover liability for all damages or losses to public and private property in the event of a worst-case scenario. The State has the authority to do so under the 1953 easement that granted permission for pipeline construction. The draft report is to date the most comprehensive cost estimate of such a worst case scenario.
The risk analysis will be paid for by funds in an escrow account the State controls and which was set up in August 2016. The funds were provided by Enbridge, but the company has no say in how the money is spent or in the findings of the independent report.
Michigan Technological University is a public research university founded in 1885 in Houghton, Michigan, and is home to nearly 7,500 students from more than 60 countries around the world. Consistently ranked among the best universities in the country for return on investment, Michigan’s flagship technological university offers more than 120 undergraduate and graduate degree programs in science and technology, engineering, computing, forestry, business, health professions, humanities, mathematics, social sciences, and the arts. The rural campus is situated just miles from Lake Superior in Michigan's Upper Peninsula, offering year-round opportunities for outdoor adventure.
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