Michigan energy regulators have reopened a case involving Enbridge’s Line 5 pipeline and the company’s request to build an underground tunnel in the Straits of Mackinac, calling for more information on the line’s current and future safety.
Pipeline critics welcomed today’s 48-page order by the Michigan Public Service Commission, which followed months of testimony from Enbridge, engineering experts, state officials, tribes, oil and gas trade groups and environmental advocates.
Following those months of expert testimony, the three-member MPSC is seeking more detailed information from Enbridge on the pipeline’s leak detection system, risk management to avoid a potential explosion within a tunnel, shutdown procedures, and how tunnel supporters determined the tunnel would carry a one in 1 million likelihood of a release.
The MPSC reopened the case “for Enbridge to file the aforementioned information and documents, and any other relevant evidence regarding the current condition, safety, and maintenance and the future safety and maintenance of the dual pipelines because this evidence ‘is necessary for the development of a full and complete record,’” according to the order.
Enbridge’s formal request before the MPSC seeking permission to build the tunnel dates back to April 2020. Since then, multiple legal challenges — including from Gov. Gretchen Whitmer and Attorney General Dana Nessel — have sought to shut down Line 5 in its current form as twin lines carrying light crude oil and natural gas liquids along the lake bed.
The tunnel proposal — devised and formally proposed during former Gov. Rick Snyder’s administration — calls for a single, 30-inch diameter pipe within a concrete-lined tunnel up to 250 feet beneath the lakebed.
In a statement following today’s order, Enbridge said it will “continue to work” with regulators to address the remaining questions.
“We believe that extensive information documenting the engineering and safety of the Great Lakes Tunnel is already included in the MPSC record and led to the MPSC professional staff recommended (sic) approval of our application based on the thorough record that has been developed to date,” the company said.
“Most notably, the MPSC decision today to continue Enbridge’s application review process has no impact on the existing pipelines across the Straits,” the company added.
The Michigan Chamber of Commerce, which also supports the tunnel project, agreed that sufficient evidence exists on the record.
“The current challenges facing our state, country and globe — surging energy demand, historic inflation, supply chain disruptions — make it clearer than ever that we need Line 5 and the Great Lakes Tunnel for our energy, economic and environmental security,” Chamber President and CEO Jim Holcomb said in a statement. “We fully agree that it’s essential all information is transparent and available, though do believe an extensive record of clear documentation denoting sound science exists. It’s time to move forward as quickly as possible to ensure our energy future, position us for economic prosperity and provide the best protection of our Great Lakes.”
Safety concerns remain
The MPSC’s order includes a focus on specific concerns raised in recent months about the potential for an explosion within the tunnel under certain conditions.
A pipeline expert in late 2021 raised these concerns and said that MPSC staff had downplayed the risk of a potential explosion, as MiBiz previously reported. An administrative law judge denied Enbridge’s attempt to strike the testimony from the record.
Environmental groups continue to oppose both the currently operating pipeline and the tunnel project, and note that Enbridge’s ongoing operation of Line 5 violates Whitmer’s November 2020 revocation of the company’s easement to operate in the Straits of Mackinac.
“We are glad to see that the Commission is taking these important safety issues so seriously,” Margrethe Kearney, senior attorney at the Environmental Law & Policy Center and an intervenor in the case, said in a statement. “We do not believe that Enbridge will be able to demonstrate the safety or necessity of either its existing dual pipelines or the tunnel it proposes to build.
“The dual pipelines must be shut down as soon as reasonably possible since they pose an immediate risk of catastrophic harm to our Great Lakes,” Kearney added. “Enbridge continues to disregard these risks, continuing to operate in violation of the Governor’s revocation and termination of its easement.”