The United States' first commercial oil sands mining project, in Utah, has been approved.

Calgary company U.S. Oil Sands has been working since 2005 to get the green light from Utah officials to develop its proposed PR Spring project.

The company anticipates that the 212-acre PR Spring project area, in the eastern part of the state, will initially produce 2,000 barrels of petroleum product a day.

Through its wholly owned U.S. subsidiary, the company has a 100 percent interest in bitumen leases covering 32,005 acres of land in Utah.

The Utah Water Quality Board voted 9-2 this week to uphold the state Division of Water Quality's decision to allow the PR Spring project to go ahead without a groundwater pollution permit because the area's groundwater is too deep in the ground to be polluted by any runoff.

That decision, U.S. Oil Sands said in a statement, "ultimately illustrates the merits that our responsible approach to oil sands development has for the environment and local communities."

On its website, U.S. Oil Sands outlines its process: "Using a unique bio-solvent the company is able to separate bitumen from oil sand without the need for tailings ponds. The process requires low energy input, recycles 95 percent of the water used and uses best practice mining methods to rapidly reclaim mined areas."

But environmentalists maintain that the mine would pollute groundwater.

Two of those groups, Living Rivers and legal ally Western Resource Advocates, say they will likely challenge this week's decision in Utah's courts.

"What we're asking for is a more rigorous oversight of this mine." Living Rivers attorney Rob Dubuc was quoted as saying by The Salt Lake Tribune.

U.S. Oil Sands Chief Executive Officer Cameron Todd told InsideClimate News that the company isn't concerned about a possible court fight, just the delays it might cause.

"We don't ever look at it as a fight," Todd said. "Rather we look at it as the company being subjected to another thorough review that will show we have a project that is of the highest industry and environmental standards."

Nevertheless, the company said the PR Spring project is on track for commercial start up late next year.

"This issue has gone through a very thorough review at many levels and at each turn it was determined that the U.S. Oil Sands operation did not pose a threat to water of any kind," Todd said.