NICOLE GAUDIANO

WASHINGTON – Vermont's senators are preparing to blast the Keystone XL pipeline in Senate floor speeches Tuesday, as proponents work to get enough votes to fast-track the controversial project.

Sen. Patrick Leahy, D-Vt., will urge colleagues not to "rubber-stamp" the project, which he says poses environmental and safety risks. The $8-billion pipeline from northwest Canada to Gulf Coast refineries would carry tar sands oil, which environmentalists say is dirtier than regular fuel.

"This pipeline is one of the most striking examples of how our unquenchable thirst for oil is destroying our environment," Leahy's prepared remarks say. "This destruction will continue until we move forward with the implementation of a comprehensive, national energy plan. The debate over the Keystone pipeline will not move us toward a sustainable energy future. Instead this pipeline ties us to an energy policy of the past, while simultaneously accelerating our impact on the climate."

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Supporters of the pipeline, mostly Republicans, say it would create jobs. It was unclear Monday if they have the 60 votes needed to block a filibuster of the bill, which would authorize the project without a presidential permit.

Sen. Bernie Sanders, I-Vt., said Friday that blocking approval of the project is a "no-brainer."

"Instead of increasing carbon emissions and accelerating climate change so oil companies can make more profits, we should put millions of Americans back to work rebuilding our crumbling infrastructure and creating a sustainable energy future," he said.

The pipeline has been delayed in the Democrat-controlled Senate but has won consistent support in the GOP House, which voted 252-161 on Friday to authorize construction of the pipeline. It was the ninth time the House has voted to pass such legislation.

The push for approval has taken on new urgency because two of the pipeline's most vocal supporters — Democratic Sen. Mary Landrieu and Republican Rep. Bill Cassidy — are locked in a heated contest for Landrieu's Senate seat in Louisiana.

Landrieu and Cassidy will face off in a Dec. 6 runoff election, and each is determined to claim credit if the pipeline bill passes Congress.

"In a blatant attempt to sway an undecided Senate race in Louisiana, this vote is being driven by raw politics over sound public policy," said Rep. Peter Welch, D-Vt., who voted against the House bill on Friday. "If this bill becomes law, Congress will have circumvented an ongoing and thorough environmental permitting process to directly issue a construction permit to a single company for a single project. And if that wasn't enough, it also grants a special earmark that exempts the pipeline's owner from a requirement to contribute to an environmental cleanup fund."

President Barack Obama has not said if he would veto the legislation.

The president has delayed a decision on the pipeline, deferring to an ongoing review at the State Department, but White House spokesman Josh Earnest suggested Thursday the president could veto the measure.

The State Department, in a January report, said the project would contribute about $3.4 billion to the economy and support about 42,100 jobs. However, those jobs would be temporary and would include direct, indirect and induced employment, according to the report.

About 3,900 jobs would be created directly in Montana, South Dakota, Nebraska and Kansas over one year of construction. If construction took two years, the project would create about 1,950 jobs each year , the report states.

About 35 permanent employees and 15 temporary contractors would be required once the pipeline began operating, according to the report.

The six-year delay has not slowed oil production by TransCanada, but it has made transporting it to refineries on the Gulf Coast more complicated.

Leahy said the existing Keystone pipeline already has spilled oil 12 times during its first year of operation, and he said tar sands oil is difficult to clean up.

"These facts are clear: The Keystone pipeline significantly worsens the problem of carbon pollution, and it is not in our national interest," he says in his prepared remarks. "The Presidential Permit should be denied, not fast-tracked by Congress."

Contributing: Susan Davis and David Jackson, USA TODAY. Contact Nicole Gaudiano at ngaudiano@gannett.com. Follow her on Twitter at www.twitter.com/ngaudiano.