One of Canada’s biggest unions estimated more than 36,000 jobs would be lost if a proposed oil pipeline from Alberta to Texas gets U.S. approval.

“The thousands of kilometres of new pipeline being proposed reveal a radical restructuring of the way oil and gas are being delivered on this continent,” reads a Toronto Star op-ed by Dave Coles, President of the Communications, Energy and Paperworkers union. “For Canadians, the consequences have been crushing.”

Calgary-based TransCanada proposes to build a 3,200 km pipeline capable of moving oil sands crude to Gulf Coast refineries. Opposition has grown steadily during past months.

Powerful U.S. congressman Henry Waxman and the U.S. Environmental Protection Agency made recent high-profile attacks.

Opponents argue the pipeline will spur carbon-intensive energy projects in Alberta’s oil sands – and risks contaminating one of America’s biggest aquifers.

The CEP’s Coles is trying to launch a second assault. More than 36,000 jobs stand to be lost if Keystone XL gets approved, he wrote.

“These pipelines are sending our raw, unprocessed bitumen from Canadian tarsands to spanking new oil refineries in the U.S.,” he wrote. “We are left with the tarsands’ massive mess. The Americans get the good jobs.”

Another TransCanada pipeline – the already-built Keystone – cost Canada 18,000 jobs, according to an Informetrica study. The CEP filed appeals against that project in 2007. It questioned the current proposal in Canada's Federal Court this May.

The U.S. Department of State, which will decide whether to approve Keystone XL, recently delayed any decision. And TransCanada itself withdrew an application for a special safety permit. The waiver would have let the pipeline run at higher than normal pressure.

Many analysts see the current controversy as an indicator of future U.S. energy policy. Strike down the pipeline, and fossil-fuel-addicted America shows it’s willing to curtail high-carbon fuel.

“The impact of the Obama-Clinton decision is so big, it may as well be a domestic Canadian issue,” wrote Fraser Institute senior fellow Alexander Moens in the Financial Post. “Are Canadians paying attention?”

Geoff Dembicki reports for the Tyee.