SALT LAKE CITY — The Bureau of Land Management announced Tuesday that a controversial proposal to expand Utah's only strip mining operation deserves another look.

Alton Coal Development is proposing to lease a tract of coal reserves outside of Alton, Kane County, that would preserve the life of its operation by up to 25 years. The BLM has estimated the area holds at least 50 million tons of recoverable coal — all owned by the federal government.

In its decision to conduct a supplemental study to its initial analysis, the agency said issues such as wetlands and air quality and increased protective measures for Greater sage-grouse habitat would be among those addressed.

"It does slow us down slightly, but overall, not very much," said Keith Rigtrup, the planner for the agency's Color Country District.

Although the BLM worked for two years with federal air quality regulators to tackle concerns raised over dust-blown pollution that could compromise night skies or the viewsheds of scenic vistas, Rigtrup said additional adjustments also need to be made in that arena.

Agencies including the U.S. Fish and Wildlife Service continue to have some concerns, he added, which will also be incorporated into the final analysis.

The draft Environmental Impact Statement was open for public comment from November through late January of this year, and during that time frame, Rigtrup said an estimated 177,000 comments were received.

"A lot of them were form letters, thousands of the exact same comment," he said, "but a lot were substantive comments. … We take every comment we get seriously."

The Southern Utah Wilderness Alliance and a number of environmental groups are steadfastly opposed to the proposal, which involves 3,500 acres of land in coal mining operation touted to provide 160 new jobs to the area and generate $6.5 million in wages over time.

Those groups are challenging the state Division of Oil and Gas Mining's decision to issue permit for the expansion of Alton Coal's existing Coal Hollow Mine, asserting the permit was issued improperly in a manner that was "arbitrary and capricious."

Arguments to that effect were held before the Utah Supreme Court in March, and a decision is pending.

SUWA's Steve Bloch said the agency's extension of the review and comment period is disappointing.

"We think the BLM had enough information from the comments it received from the National Park Service, the Fish and Wildlife Service and the EPA," he said. "It's not clear why they need to go through this exercise, as opposed to simply rejecting the proposal at this point."

Bloch said the added review and time just throws more uncertainty into the mix.

"Moving it down field creates a lot of uncertainty from all sides," he said, "but certainly from the conservation community about what the future holds for the doorstep at Bryce Canyon National Park."

In this added layer of analysis the BLM intends to provide, another round of public comments will be accepted once that document is finished, most likely in early 2013.

Additional tweaking will be done based on those comments received before the agency issues a final document, after which an official record of decision will be made.

"No one could accuse us of rushing to judgment," Rigtrup said, noting the company's application was filed in 2004 and once the draft review was initiated in 2006, it took five years to complete.

"This is a controversial issue," he said. "A lot of people are watching. … The BLM's job is to thoroughly analyze those issues and look at the benefits and negative aspects of that and issue a decision."

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