Norman Wells, a remote town in the Northwest Territories, ranks as the community with the most reported incidents on federally-regulated pipelines in the country, a fact that's surprised key community members. 

Records obtained by CBC News from the National Energy Board (NEB), Canada's pipeline regulator, show more than 70 incidents — anything from spills and leaks to worker injuries and fires — near the town between 2006 and 2012.

All but a handful of the issues happened at Imperial Oil facilities, which includes sprawling operations near the community on the banks of the Mackenzie River.

Some involved leaks of several litres to several thousand litres of crude oil, and Imperial Oil considered most to have no environmental impact once cleaned up.

But a number of events stand out. In 2006, more than 40,860,000 litres of water used for cooling by the company was released back into the Mackenzie River with elevated levels of copper.

In 2009, 127,000 litres of water contaminated with hydrocarbon that was used to help force oil up from deep underground, also poured into the river.

"It's shocking to me," says Dudley Johnson, who was mayor of Norman Wells for three years until 2012. "I never heard of these incidents. The rule is, they must report it to the municipality."

77 lines under scrutiny

The spill record also came as a surprise to former Member of Parliament, Ethel Blondin-Andrew, who chairs the Sahtu Secretariat Incorporated, which oversees the regional aboriginal land claim.

"There's definitely a need for the board of directors to meet with both the NEB and Imperial Oil to have a discussion on this," said Blondin-Andrew.

Both Johnson and Blondin-Andrew were also concerned to learn that this past summer the federal pipeline regulator had ordered Imperial to come up with a comprehensive plan to deal with 77 buried pipelines at risk of failing.  

The lines, some of which stretch for several kilometres, were installed during a boom in the oil field expansion in the 1980s. A defect allowed water to get between the pipe insulation and the bare steel, leading to corrosion.

Imperial first identified the problem in 2011, after discovering oil seeping to the surface on Bear Island, one of its well sites on the Mackenzie River. 

Over the next year and half the company found a total of six leaks, including an "historic release" from an abandoned pipeline. Cleanup involved the excavation of thousands of cubic metres of contaminated soil.

Imperial's preliminary plan called for replacing lines shorter than a kilometre and inspecting, repairing and monitoring the longer ones.

"Replacement would result in a significant increase in cost while providing only minimal additional risk reduction," Imperial's report to the NEB stated.   

But the plan was rejected by the regulator as incomplete because it failed to deal with all of the suspect pipelines.

"We want to make sure all the 77 pipelines were addressed", says Bharat Dixit, NEB's technical leader of exploration and production.

No big concerns: mayor

Dixit says on the whole, Imperial's record of more than 70 reported incidents in seven years is not unusual.

"[It's] reflective of the kind of incidences we may see nationally and internationally in a similar sized facility," he said.

hi-mackenzie-river-852-7237

Imperial Oil's water licence, which sets limits on its use of river water and how contamination must be monitored, is currently under review.

But while many of the spills are benign, Dixit says all are important and the major ones, including the water releases and pipeline breaches cited by CBC, are of concern. 

The incidents will also be noted by the Sahtu Land and Water Board, which is currently reviewing Imperial's application to renew its water licence. That licence, which sets limits on the amount of water the company can draw from the river and how it must monitor contamination, was granted nearly 10 years ago and is set to expire next August.  

But the board's executive director, Paul Dixon, says Imperial's record is not a surprise and the company has never withheld details of any accident, no matter how small.

"If there's anything that's over the 100-litre limit, they give us a courtesy email or call about that as well," said Dixon.

The relationship between Imperial and Norman Wells goes back to the first producing well in 1920. Currently, there are nearly 400 wells, many built atop natural and artificial islands in the Mackenzie River, reaching down half a kilometre into the 400-million-year-old oil deposits. The town of 800 relies on the company.

"I don't have any big concerns about how they do things out there", says Mayor Gregor McGregor.

Unlike his predecessor, McGregor doesn't see that Imperial has any obligation to tell the town about incidents it's already reporting to the NEB.

"We can speak with Imperial Oil people anytime", McGregor says. 

"Matter of fact, I had a meeting with the manger out there on Friday, just to bring myself up to date. We had her go over the ones you mentioned," McGregor says, referring to a synopsis of incidents CBC news provided him.

While McGregor got a meeting within minutes of speaking to Imperial's operations manager, the company declined CBC's request for a visit to the site. 

Company goal of zero spills

In an email, Pius Rolheiser, a company spokesman, wrote the company is "focused on maintaining safe, efficient operations" and visitors or tours "can be a distraction and get in the way of that."

li-imperial-oil-620

There are nearly 400 wells built atop natural and artificial islands in the Mackenzie River. (Imperial Oil)

The company also declined requests for interviews. Instead, Imperial responded to a selection of incidents CBC News raised as examples.

Rolheiser wrote that "Imperial's goal is to drive spills with environmental consequence to zero," and he highlighted a 2008 NEB audit which concluded Imperial had  "adequate, effective and ongoing proactive processes" to "eliminate or control … risks associated with its activities."

He said the copper levels in the 2006 release of water into the Mackenzie River, were "well below" Canadian drinking water guidelines. The spill of contaminated water in 2009 led to a redesign of equipment related to the failure. 

As for the NEB's concern about corroding pipelines, Rolheiser wrote that Imperial's efforts to "manage the risk of aging pipelines meet or exceed regulatory requirements."

If you have any pipeline-related stories, please email us at pipelines@cbc.ca.