The Teamsters union warned good jobs are at risk Monday over a decision by the Obama administration to stop construction on the Dakota Access Pipeline.

After twice defending its approval process in court, with victories in both cases, the U.S. Army Corps of Engineers reversed course when it announced Sunday that it would not approve construction permits needed to finish the project. The Teamsters argued the decision will hurt working Americans.

“The decision will have a direct and negative impact on the hardworking men and women—including Teamsters and other union members—who have invested their lives in building the infrastructure that makes this country run,” the Teamsters said in a statement provided to InsideSources. “The Teamsters Union looks forward to moving past this disappointing decision toward the eventual approval of this easement and completion of the Dakota Access Pipeline.”

The Standing Rock Sioux tribe and its supporters claim the nearly completed pipeline runs too close to sacred tribal burial sites and could affect the tribe’s water supply, though the pipeline never crosses onto tribal land. The Laborers’ International Union of North America (LIUNA) argues the Obama administration is “appeasing environmental extremists.”

“Blocking the final portion of construction of the Dakota Access Pipeline after it is 93 percent complete and fully reviewed is a short-sighted, gutless, and irresponsible decision,” LIUNA President Terry O’Sullivan said in a statement Sunday. “It only serves to prolong the conflict that is dividing communities in North Dakota.”

Labor unions have historically sided with Democrats except when policies threaten their members’ livelihoods. The Teamsters represent more than 1.4 million workers from a range of industries. LIUNA has over a half-million members primarily in the energy and construction industries.

“Although we have had continuing discussion and exchanges of new information with the Standing Rock Sioux and Dakota Access, it’s clear that there’s more work to do,” Army Assistant Secretary Jo-Ellen Darcy said Sunday. “The best way to complete that work responsibly and expeditiously is to explore alternate routes for the pipeline crossing.”

Labor unions have been highly critical of the administration over similar efforts in the past. The Keystone XL Pipeline faced fierce opposition from critics who argued it would harm the environment. LIUNA and the Teamsters opposed efforts by the president at the time to delay and eventually derail the Keystone pipeline.

Critics claim Dakota Access poses a threat to the environment. O’Sullivan argues the pipeline actually poses little risk to the region because it will be safely constructed. He adds there are already fourteen pipelines going under the Missouri River that are not causing any issues.

“The Standing Rock Sioux Tribe had opportunity after opportunity to weigh in on the process during the last two years and only recently after the pipeline was almost complete decided to engage,” O’Sullivan said, referring to repeated efforts by the corps to meet and discuss the pipeline route. “This pipeline will be safely constructed to bring energy where it’s needed – without exposing communities to the unnecessary risk caused by transporting fuel by rail or truck.”

O’Sullivan notes the decision is also pointless since the courts or President-Elect Donald Trump will likely overturn it. He adds previous court decisions have already ruled the project was lawfully reviewed and community input was adequately considered.

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