Canada’s National Energy Board announced Thursday it has approved the reversal of a pipeline that would bring oil sands from Alberta to a refinery in Montreal and closer to Maine.

The Energy Board’s decision, which was published in a news release on its website, gives Enbridge Inc. the authority to reverse more than 500 miles of its pipeline between North Westover, Ontario and Montreal, Quebec.

“Enbridge will be permitted to react to market forces and provide benefits to Canadians, while at the same time implementing the project in a safe and environmentally sensitive manner,” the Energy Board said.

Environmentalists in Canada and Maine contend the reversal is part of a longer-term plan to export oil sands – called tar sands by opposing groups – from Alberta through ports along the eastern coast of Canada and the United States, including a Canadian-owned oil terminal based in South Portland.

No one has presented a plan to export oil sands through South Portland, but the city is engaged in a long-running debate about possible waterfront zoning rules to prevent any flow of crude through the city.

Sen. Angus King, I-Maine, and Rep. Chellie Pingree, D-Maine, released statements Thursday saying the decision raises the stakes for Maine and both have called on the Obama administration to assert regulatory authority over any future proposal that calls for a reversal of the Portland-Montreal Pipeline in order to pipe tar sounds south through Maine.

“Today’s decision brings toxic tar sands oil right to New England’s doorstep, and one step away from flowing south through Vermont, New Hampshire, and Maine,” Dylan Voorhees, Clean Energy Director for the Natural Resources Council of Maine, said in a news release. “This decision should put Maine on high alert for the threat of tar sands transportation through our state.”

Portland Pipe Line Corp. operates a 236-mile underground pipeline that pumps crude oil from tankers in South Portland to the refinery in Montreal that is connected to the Enbridge pipeline. A company spokesman repeated the company’s assurance that no reversal is planned.

“Portland Pipe Line Corporation’s previously stated position that there is no project to reverse the flow of its pipeline proposed, pending or imminent is unaffected by announcements regarding other Canadian pipelines,” Portland Pipe Line spokesman Jim Merrill said in an email Thursday.

Environmentalists remain skeptical. Critics say the crude oil – a combination of sticky bitumin, sand and water – is dirtier to refine and is far more dangerous to ship through pipelines, posing health, environmental and public safety hazards if a spill were to occur.

The Portland to Montreal pipeline passes along and under the Androscoggin River, crosses the Crooked River six times, passes alongside Sebago Lake – the drinking-water source for Portland and several neighboring communities – and ends on Casco Bay in South Portland.

Oil companies, including Portland Pipe Line, say oil sands are no riskier to pump through a pipeline than traditional crude that has been flowing through the Maine pipeline for decades.

Staff Writer Dennis Hoey can be contacted at 791-6365 or at:

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