"It's an extension of what we've been doing versus shutting down," said Ken May, the mine's general manager. "It's perpetuating energy development and protecting jobs."
The EIS looks favorably on pulling more coal from under Fishlake and Manti-LaSal national forests, but it proposes requiring the mine to take steps protect sage grouse habitat, water, roadless lands and other non-energy resources. It also proposes allowing only room-and-pillar mining over part of the lease area to protect perennial streams from subsidence associated with longwall mining, according to Marianne Orton, environmental coordinator for Fishlake National Forest.
The Forest Service released the review Friday and opened a public comment period through April 28.
The Greens Hollow project area covers 6,175 acres to the northwest of Sufco's current operations and would yield 56.6 million tons of coal, generating $194 million in royalties and tax revenues.
Two years ago the Forest Service approved the lease, which would be administered by the Bureau of Land Management. But after environmentalists appealed, Fishlake's Forest Supervisor Allen Rowley withdrew the decision and initiated the supplemental review. Critics argued the first decision failed to adequately protect sage grouse, a candidate for listing as an endangered species, and roadless areas.
Operations had already permanently reduced North Fork Box Creek, according to the Grand Canyon Trust's Mary O'Brien.
But May said his underground mine results in few surface impacts.
"We are more concerned about the environment than anyone from outside the area," May said. "We live here and recreate here. We don't want to do anything to disrupt the local environment."
A rich but dwindling seam • Sufco would access Greens Hollow coal from existing underground longwall operations that mine coal in sliced panels, tapping in new ventilation shafts as they progress.
But May cautioned the lease would be subject to competitive bidding and another operator could win it.
Sufco produces low-sulphur bituminous coal, most of which is burned in the 1,138-megawatt Hunter power plant in Castle Dale and two other plants in Carbon and Emery counties. Rocky Mountain Power has contracted to purchase up to 4.5 million tons of Sufco coal a year through 2020, according to utility spokesman Dave Eskelsen.
Over the past seven decades the mine has yielded 170 million tons from the Hiawatha coal bed. The seam, up to 14 feet thick, is part of the Blackhawk Formation, laid down in late Cretaceous Period 75 million years ago when fecund swamps covered what is now the Wasatch Plateau.
Deep rich layers of peat accumulated in these bogs and was compressed into hydrocarbon deposits that pack more than 11,000 Btus per pound, according to David Tabet of the Utah Geological Survey. A British thermal unit is the amount of energy needed to heat a pound of water by one degree Fahrenheit.
Sufco has long worked a continuous, flat seam not too far beneath the surface that made for ideal mining conditions.