TC Energy Corp. has awarded six U.S. union contractors $1.6 billion in contracts to build the long-delayed and controversial Keystone XL Pipeline in 2021, to move up to 830,000 barrels per day from the tar sands of Hardisty, Alberta, to Steele City, Neb., where it would connect to pipelines to Illinois and the Gulf Coast.

The companies awarded contracts in late October for the $8-billion pipeline, the focal point of a contentious environmental battle since first proposed in 2008, are Barnard Pipeline of Bozeman, Mont.; Associated Pipeline and U.S. Pipeline, both of Houston; Michels of Brownsville, Wis.; Precision Pipeline of Eau Claire, Wis.; and Price Gregory International of Katy, Texas.

The project would cover 1,209 miles—327 miles of pipeline in Canada and 882 miles in Montana, South Dakota and Nebraska.

Richard Prior, president of Keystone XL Pipeline, said in a statement, that construction activities are already underway in both the U.S. and Canada.

“The selection of our U.S. construction contractors for 2021 is an important next step in employing thousands more American union workers and delivering tangible benefits to local communities and businesses,” he said.

According to TC Energy, contractors will hire more than 7,000 union workers in 2021. That number will exceed 8,000 when other contracts are announced later. Keystone XL is expected to employ more than 11,000 workers next year, TC Energy said.

The company said contractors were selected based on their experience in pipeline and major infrastructure projects in the U.S. and globally.

Price Gregory International Inc. will construct about 155 miles of large diameter pipeline in several counties in Nebraska and South Dakota.

According to a statement on its website, the company expects to hire about 1,200 workers during the anticipated two-year construction period and has committed to hiring locally.

Construction is expected to begin next summer near Winner, S.D. and finish near Norfolk, Neb. in 2022.

The controversial pipeline, which drew protestors who cited climate change impact as one reason for their opposition, was halted in 2015 by President Barack Obama and revived in 2017 by President Donald J. Trump.

Alberta’s provincial government relaunched some work last spring with a $1.1-billion equity investment.

More recently, pipeline work has been stalled by a legal fight over stream-crossing permits issued by the U.S. Army Corps of Engineers. The case is pending before a federal appeals court.