Enbridge To Test Safety Of Pipeline Running Through Superior

Enbridge Energy is testing the safety of one of its pipelines running through a corner of northern Wisconsin this week, following an internal analysis of the line.

The firm will be looking at a segment of pipeline running from Clearbrook, Minnesota to its Superior terminal. The section is part of Line 2, a pipeline that’s had issues in the past: It spilled around 3,800 barrels of oil in Neche, North Dakota, in January 2010.

Shannon Gustafson, the firm’s media relations manager, said Enbridge decided to conduct a test on Line 2 after an internal analysis of its design, inspection findings and limits on operation. The company tested another segment stretching from North Dakota at the Canadian border to Clearbrook last week, which she said “satisfied regulatory requirements.”

According to Gustafson, the plan is to remove all oil from the Clearbrook-Superior segment and then flush dyed and chlorinated water from the Red River through it at high pressure.

“Then, we hold that pressure for a certain amount of time to check the integrity of the pipe,” said Gustafson.

According to Gustafson, it’s part of what’s called a “hydrostatic test” — a common means of ensuring that pressure vessels are strong and secure.

The company is setting up booms in waterways along the pipeline to collect any releases as they conduct the test over the next several days. Enbridge will also work with the Wisconsin Department of Natural Resources on discharging water from the test into tributaries that run into the Nemadji River, which drains into Lake Superior.

Several people voiced concern over water from those tests being released into the river at a DNR public hearing in Superior last month regarding the company’s application to renew its Wisconsin Pollutant Discharge Elimination System permit with the state. The permit covers discharge of waters from such tests at the Superior terminal.

“I find no reason to discharge into the Nemadji River when we do have a wastewater treatment facility available,” said David Conley, a resident of Lake Nebagamon.

Gustafson said Enbridge treats the test water at its terminal in Superior before it’s released.

“The test water will be treated through a series of filters and activated carbon vessels before discharge,” she said.

The treatment process is expected to take 15 to 20 days for the Line 2 test.

Others have voiced concern over public notice of tests that are conducted and whether the findings from the tests are shared. Gustafson said they’re required to share results with the Pipeline Hazardous Materials Safety Administration for review.

The DNR ultimately reissued Enbridge’s five-year discharge permit on Tuesday, which takes effect in October. Sheri Snowbank, a wastewater specialist with the agency, said at the August meeting that Enbridge was in “substantial compliance” with the permit.

The energy firm is still required to seek department approval for test water that originates from anything other than local sources to prevent the spread of invasive species.

A spokeswoman with the DNR did not immediately return a request for comment Tuesday regarding the department’s role overseeing the test.

Enbridge has performed similar tests on Line 14 in Wisconsin with no issues, as well as Line 5 in Michigan.