An energy company received federal approval Thursday to open one of Utah's biggest natural gas fields by agreeing to use new technology to drill under wild areas, instead of on top of them.

The Bureau of Land Management's approval of Bill Barrett Corp.'s multi-billion-dollar project reflects a deal the drilling company made with environmental groups to pull back from wild areas and limit well pads off the high rim of the Green River's Desolation Canyon.

That canyon, a National Historic Landmark inside one of the Lower 48's largest roadless areas, has seen little change since explorer John Wesley Powell remarked on "a region of wildest desolation" while boating the river in 1896. The area is populated by elk, deer and bighorn sheep, and bear maulings of river runners are not uncommon.

Along the river's western ramparts, Bill Barrett plans to use 120 well pads instead of the 538 it originally proposed, and it will drill directionally instead of straight down to get at the gas pockets deep beneath wild lands. It promised to hide wells into folds of the landscape and limit development activity during summer so rafters on the Green River can't spy the company's trucks or rigs from thousands of feet below.

"We think it's one of the most environmentally progressive natural gas projects," said Duane Zavadil, a vice president for Bill Barrett Corp.

Shares of the Denver-based company climbed $1.62, or 5.1 percent, to $33.73 in midday trading.

Interior Secretary Ken Salazar hailed the company's compromise and called the agreement historic.

"It clearly provides for the orderly and balanced development of our nation's energy supply while, at the same time, serving as an outstanding example of the fresh look of how we can better manage our energy resources," Salazar said in a written statement.

In one case, Bill Barrett dropped plans to develop wells around Jack Canyon, a tributary to the Green River, where the steep, rugged terrain is dotted with dense pinion and juniper trees and visited by a herd of wild horses. Jack Canyon is a candidate for wilderness protection, but because it has a well head that was drilled years ago, it was considered fair game for more development.

Now, Jack Canyon will be left untouched.

Utah BLM director Juan Palma called the settlement "a big deal" that came after years of environmental review and negotiation. The agency issued a final environmental study Thursday along with a decision to approve the project.

"This is a wonderful example of finding balance," Palma told The Associated Press on Thursday. "It's the kind of collaboration we need. It is not the environment against the economy. It's the environment and economy working together."

The Southern Utah Wilderness Alliance agreed not to challenge the agency's approval in federal court after the company stepped back from lands the group is proposing for wilderness designation by Congress.

Steve Bloch, a staff lawyer for the wilderness group, said the lands were as dramatic as Arizona's Grand Canyon.

"It's a remarkable, awe-inspiring landscape," Bloch said. "The compromise was hard fought, but we're pleased we found a partner in Bill Barrett Corp. to protect this special place."