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A cheat sheet to the Enbridge Line 5 controversy

Enbridge protester

Bridge Magazine provides the least you need to know about the ongoing battle over Line 5, Enbridge’s twin oil pipelines that run along the bottom of the Straits of Mackinac. Should the state shut it down? Read this Bridge primer on the controversy before you decide:

May 2018: Opinion | Here are 6 billion reasons to care about a Line 5 spill
May 2018: Enbridge fined $1.9 million for inspection woes on Line 5, other pipelines
Related: Bipartisan consensus grows to shut down Enbridge Line 5

What is Line 5?

A 30” diameter, 645-mile pipeline that carries light crude oil and liquid propane from Superior, Wis., through Michigan's Upper Peninsula and then splits into two 20-inch diameter parallel pipelines that cross just west of the Mackinac Bridge on the lake floor of the 4.6-mile long Straits of Mackinac (which connect Lake Michigan and Lake Huron). It then travels south through the Lower Peninsula, until slanting east from Bay City and crossing under the St. Clair River at Sarnia, Ont. where most of the oil goes to gasoline refineries. Some oil goes to the Marathon Refinery in Detroit and some is shipped overseas.

How and when did Enbridge get the right to put in the pipeline across the lake floor of the Straits?

The State of Michigan granted the request of Enbridge, a $125-billion Alberta, Canada-based oil transport company, for a right-of-way to build, lay and secure two pipes along the lake bottom in the Straits. The pipelines became operational in 1953. Today, they carry up to 23 million gallons daily of light crude oil and liquid natural gas (for propane). Michigan Attorney General Bill Schuette and others have said the right-of-way would not have been be granted if requested today.

Are there benefits to Michigan of having Line 5?

Enbridge says there are many. It says Line 5 supplies 65 percent of the propane used in the Upper Peninsula and 55 percent for the entire state and also says that 30 percent of the crude oil from Line 5 ends up at the Marathon refinery in Detroit to be turned into gasoline for Michigan motorists. Opponents say those numbers are exaggerated. “A very small amount goes to the Marathon refinery,” said Mike Shriberg,” regional executive director for the National Wildlife Federation’s Great Lakes Office in Ann Arbor. Enbridge also says that in 2016, it paid about $55 million in Michigan property taxes for using land its pipelines cross. Enbridge also pays for about $8 million in salaries to 103 employees in Michigan.

What's the risk of a spill?

Enbridge says the risk of a pipeline rupture is extremely small because the pipelines were built to the highest standards, the company goes above and beyond its regulatory requirements to monitor and upgrade the condition of the pipeline in the Straits and recent pressure tests proved the pipes withstood pressure many times higher than exists when oil is flowing.

But critics say that even if the risk is small, the impact of a rupture could be catastrophic. They cite that the pipes were built more than 60 years ago and the strong and changing currents on the bottom of the Straits (the water flow through the Straits is 10 times that of Niagara Falls) put enormous stress on the pipes.

Perhaps the biggest recent bombshell raising concerns about the Straits pipelines’ integrity came earlier this month when U.S. Sen. Gary Peters released a report that had been delivered to Enbridge in October 2016 as part of the company’s settlement with the federal government over its 2010 catastrophic spill into headwaters of the Kalamazoo River. The report noted that when the Straits pipelines were examined in 2003, bottom anchors to secure the pipes and required every 75’ by the right-of-way agreement with the state were missing in many places. Specifically, 16 locations had at least 140 foot spans unsupported by anchors. The longest was 224 feet on the west pipeline and 286 feet on the east pipeline. While Enbridge corrected the missing support problem and others identified since then, critics say it appears the unsupported spans could have existed for decades, putting damaging stress on the pipelines.

Ed Timm, a retired Dow Chemical Co. engineer who authored a technical analysis of Line 5 for the National Wildlife Federation, told MLIVE.com that the neglect of the Straits pipelines between 1953 and 2003 has left them “one peak current event” away from failure.

What is Enbridge’s track record on spills?

Again, it depends on who is framing the response. Enbridge points out, correctly, that it has had no spills or leaks from the twin pipes that cross the Straits in their 64-year history. But a National Wildlife Federation researcher found that there have been 29 spills since 1968 of at least 1.13 million gallons of oil along Line 5, though none were in the Straits themselves.

But the Enbridge pipe rupture that got Michigan regulators, politicians, activists and ordinary residents keenly focused on Line 5 took place in July 2010. That’s when a six-foot section of Enbridge Line 6B ruptured near a creek that drained to the Kalamazoo River in southwest Michigan. It was one of the worst freshwater inland oil spills ever in the U.S. Over four years of cleanup, more than 1.2 million gallons of crude oil was recovered and Enbridge has paid nearly $1.3 billion for cleanup and restoration.

The Kalamazoo spill continued for 17 hours before Enbridge shut off the flow after a utility company employee noticed the pooling oil and notified authorities. Enbridge employees were alerted to a pressure loss by company monitors but initially dismissed the notification as a false alarm. Enbridge says pipeline shutoffs after a rupture are now automatic.  Asked whether Enbridge’s improvements are reassuring, Liz Kirkwood, executive director of For Love of Water, a Traverse City-based Great Lakes advocacy group, said Enbridge’s failure on Line 6B explains her skepticism about any company claim on safety.

What would be the impact of a pipeline rupture in the Straits?

That would depend on many things. A University of Michigan 2014 study funded by the National Wildlife Federation's Great Lakes Regional office found that in a worst-case scenario, more than 700 miles of Great Lakes shoreline could be significantly contaminated. The study noted currents in the Straits that unpredictably change direction and strong winds that can funnel into the area from various directions. Winter ice could make oil recovery difficult, if not impossible for work boats. Environmental damage to birds and fish also could be significant. And a heavily publicized, major spill could do long-term damage to areas where tourism is critical to the economy.

Enbridge strongly challenged the U-M study, saying its new automatic shutoff system, the opening of a fully-staffed response office in St. Ignace and other improvements would minimize any damage in the unlikely event of a spill.

Should we believe Enbridge?

On the one hand, it's in Enbridge's financial interest to prevent a catastrophic spill in the Straits with estimates of a potential cleanup running as high as $10 billion or more, depending on many factors. In its investigative report on the Line 6B Kalamazoo River spill, the National Transportation Safety Board cited “pervasive organizational failure” by Enbridge. Specifically, the NTSB said Enbridge was aware of a stress fracture in the six-foot section of pipe that ruptured and did nothing. It also noted inadequate training of the staff.

Gail Gruenwald, executive director and staff attorney for the Tip of the Mitt Watershed Council, acknowledged that Enbridge “is waking up to the things they need to do.” But she said her organization still took a strong stand, calling for the closure of Line 5, because the potential for short and long-term damage is untenable. “The lack of transparency is the most frustrating thing with trying to get information about this pipeline.”

What happened to the two reports the state commissioned from  independent contractors on the risks and alternatives to using the Straits as a crossing for the Line 5 pipelines?

The risk report was abruptly shelved last week when the state announced it had fired the contractor hired to produce the report after learning in late May that someone responsible for a key portion of the analysis also was working simultaneously on a separate report for Enbridge. Citing the contract’s conflict of interest clause, the state terminated the contract. No decision has been made yet on whether the state will now commission a risk-analysis report from another firm.

Some estimated starting the process from scratch could set back a final decision on Line 5 for more than a year. Meanwhile, the state plans to proceed with its anticipated release this week of the second report, which examines alternatives to Line 5 for moving Enbridge light crude oil to refineries. Public hearings on that will be held in July (see details below).

Among the anticipated options are using other pipelines routing around Lake Michigan, building a new pipeline through the Straits, building a new pipeline under the Straits bottomland, or building a new line through Ontario.

How can I have a voice after the alternatives study is released?

Interested parties, including residents, will have one month to comment on the findings. The first public forum on the alternatives study will be at 5 p.m. July 6 at Holt High School in Holt to explain the report and answer questions. The next three hearings are for public comment. They are scheduled for:

  • 8 a.m. Monday, July 24 at Holt High School

  • 6 p.m. Monday, July 24 at the Hagerty Center in Traverse City

  • 6 p.m. Tuesday, July 25 at Little Bear East Arena in St. Ignace.

What happens after that?

It’s not clear and depends on what state officials decide on whether another risk study is needed. Eventually, perhaps by early 2018, it is expected that Gov. Rick Snyder or Attorney General Bill Schuette will determine a legal and political strategy to either shut down the Straits pipelines, or somehow force Enbridge to show greater accountability and transparency in its safety and testing procedures.

Are there citizen efforts underway to curtail Line 5 transport of crude oil?

A petition drive began in early May that would allow Enbridge to transport liquid natural gas products (but not oil) in the two pipelines across the Straits. Proponents must collect 252,523 valid signatures of registered voters by Dec. 1. If they do, the Legislature could vote to enact their petition as law. If the Legislature rejects the proposal, it would go on the Nov. 1, 2018 ballot.

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