State of Michigan Says Line 5 Report Inadequate

Posted on August 9, 2017 by

The Department of Environmental Quality, Department of Natural Resources, Michigan Agency for Energy, Michigan Public Service Commission, and Attorney General’s office (collectively referred to as “the State”) filed their public comments on the draft Alternatives Risk Analysis for Enbridge’s Line 5 under the Straits of Mackinac on Aug. 4.

State regulatory agencies ordered Dynamic Risk Assessments of Calgary, Canada to revisit the draft risk analysis and broaden potential oil spill impacts, consider historical stress on the pipeline’s integrity, and explain in detail how long the line can reasonably operate without replacement.

Notably, many of the concerns shared by the state are the same concerns raised by citizen groups and individual commentators, showing that public input has made a significant impact.

According to the State, the draft report submitted by Dynamic Risk—

  • does not asses the “worst case” scenarios as stipulated by the contract, especially types of spills that may evade detection or occur during periods of thick ice cover.
  • “does not document or explain how the spill costs estimates for Alternative 5 adequately account for various impacts, including, but not limited to ecological effects, drinking water supplies, property values, and the regional tourism economy.”
  • “does not acknowledge, or attempt to take account of other publicly available information about the estimated costs of a worst case spill,” ignoring even Enbridge’s own estimation of a $450 million to $1 billion cleanup cost. The Dynamic Risk report estimated a $100 million to $200 million spill cost.
  • “does not offer any explicit conclusion about how long the existing pipelines can reasonably operate without replacement.”
  • lists “fatigue caused by vortex-induced vibration” and “overstrain” caused by strong currents beating on long unsupported spans of pipe as a primary potential cause of failure, but “did not address, and apparently failed to consider the related issues of whether, and to what extent, the past exceedances of the 75-foot span limit, both before or after 2005, may have potentially, in combination with the high currents in the Straits, adversely affected the integrity of the pipelines and their susceptibility to failure.”
  • did not consider “publicly available” information about historical exceedance of the pipeline’s easement, which does not allow any unsupported spans greater than 75 feet. The analysis focused only on inspection reports in the decade between 2005 and 2015.
  • did not account for extreme variation in the ice cover during winters in the Straits of Mackinac in the spill models.
  • estimated a much more localized oil spill dispersion risk than the highly-cited University of Michigan scientist David Schwab.
  • disregarded existing infrastructure (pipelines and terminals) that could move Line 5 product to refineries in Detroit, Toledo and Sarnia, Ontario.
  • failed to account for the economic impact of reducing propane supply for the Lower Peninsula if Line 5 is shut down.

Last week was the start of 15-day period ending Aug. 19 during which replies to the public comments can be posted online at the state’s Line 5 website.


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