An Enbridge crude oil pipeline in Minnesota that exploded, killing two workers, is expected to reopen within three days, the company said Thursday.

Flames and smoke rise above an oil pipeline fire that killed two workers near Clearbrook, Minn., on Wednesday.
(Eric Hylden/Grand Forks Herald/Associated Press)

Calgary-based Enbridge said two employees repairing a pinhole leak in the pipeline were killed in the blast Wednesday night about five kilometres southeast of the Enbridge Energy Partners terminal in Clearbrook.

The pipeline, which takes oil to the U.S. Midwest from Saskatchewan, contains four conduits. The heavy crude line involved in the explosion is expected to be back in service in two to three days, Enbridge said.

"This is a tragic day in our company's history. We've had a presence in this community for more than 50 years and this incident hits close to home for all of us at Enbridge," said Richard Bird, Enbridge's executive vice-president for liquid pipelines.

In April, the same pipeline ruptured in Saskatchewan. Enbridge has had two other leaks in its Canadian lines since 2001.

The deaths in Minnesota highlight safety concerns Alberta's oilpatch has been struggling with, as workplace injuries have dramatically increased over the past five years, said Gil McGowan, president of the Alberta Labour Federation.

"During a boom, the unfortunate reality is that corners are much more likely to be cut, and one of the first corners that is often cut is health and safety," he said Thursday in Edmonton.

Pipeline failures low in Canada

The Canadian Energy Pipeline Association defended pipelines as the safest way to transfer oil and gas.

"It's still the safest way to move large volumes of oil and gas, much safer, for example, than moving them by rail or truck or by boat," said David MacInnis.

In Alberta, pipeline failures are down 30 per cent since 2000.

"When you look at number of failures that occur in different countries in the world — I'm talking transmission pipelines — we have the best record in the world. It's continually improving," said William Shaw, head of pipeline engineering at the University of Calgary.

Disruption triggers price surge

The pipeline carries about 15 per cent of crude imports to the U.S. and in the current market, any event that reduces the already tight world oil supply boosts prices, said Michael Tims, chair of Peters and Co., an energy investment firm in Calgary.

"Every single variable takes on increased importance and that's exactly what we're seeing here, which is that in the whole global scheme of oil, it's not that major an event but it does have an effect and in a tight situation, the price does react."

The price of oil surged more than $4 US per barrel overnight just after the explosion, but gradually gave up most of its gain. The January contract for light, sweet crude finished with a rise of 39 cents at $91.01 US a barrel on the New York Mercantile Exchange.

With files from the Canadian Press