"Mr. President, this department has climbed the mountaintop in terms of achieving the goals we set out to accomplish," Norton wrote in a letter to President Bush. "Now I feel it is time for me to leave this mountain you gave me to climb, catch my breath, then set my sights on new goals to achieve in the private sector."

There is no word on who might replace Norton. Deputy Interior Secretary Lynne Scarlett will serve in the interim.

The Interior Department manages one-fifth of the land in the United States, more than 500 million acres overall, including 24 million in Utah. It oversees 388 national parks, 545 wildlife refuges, and 472 dams. It also has jurisdiction over American Indian issues.

Norton oversaw a huge expansion in oil and gas development in the Rocky Mountain West, more than doubling the number of permits processed by the Bureau of Land Management, with 10,500 applications anticipated next year. In Utah, there were 248 applications to drill in 2000 and 578 in 2004.

Reviews of her tenure were wildly divergent.

The president, industry representatives and Utah's Republican members of Congress hailed Norton and her service while environmentalists panned her performance.

The Defenders of Wildlife met the announcement with a two-word statement from its president, Rodger Schlickeisen: "Good riddance."

But Bush praised Norton, calling her "a strong advocate for the wise use and protection of our nation's natural resources and a valuable member of my administration. . . . I appreciate Gale's dedicated service to our country."

Norton, who turns 52 today, was the first woman to serve as Interior secretary. Her resignation will take effect at the end of the month. She was one of four secretaries remaining from Bush's original Cabinet.

Norton said she doesn't have a job lined up, but plans to take some time off and look at opportunities in the private sector. And she said she looks forward to visiting a national park without holding a news conference, enjoying wilderness without a reporter over her shoulder, and hopes to do more skiing.

Sen. Orrin Hatch, R-Utah, said Norton "brought grace and balance to one of the most difficult and thankless jobs in government."

"After eight years of [President] Clinton's command-and-control approach to managing our public lands, Secretary Norton instilled a sense of cooperation and open communication to public land management," he said.

Utah Republican Rep. Chris Cannon, chairman of the Congressional Western Caucus, lauded Norton as "intelligent, hard-working [and] determined."

But Scott Groene, executive director of the Southern Utah Wilderness Alliance, which frequently sparred with the Interior Department, said Norton's tenure deserves "two thumbs down."

"Norton came in as an industry flack and operated as one and presumably that's what she's headed back to," said Groene. "Norton's legacy was trying to undermine federal laws written to protect our public lands to the extent possible. The question is to what extent did she succeed."

Norton lobbied for the successful passage of the Healthy Forests Initiative, which eased logging restrictions, and the Energy Policy Act. She was the leading administration proponent of opening the Arctic National Wildlife Refuge to oil drilling, which has been blocked by Congress.

Under her guidance the department also made a major investment in refurbishing National Park roads, structures and campgrounds, with about 6,000 projects under way. The Interior Department has a staff of more than 70,000 employees and a budget of nearly $11 billion.

"There will never be a perfect time to leave," Norton wrote to Bush. "There is always more work to do. My leaving now gives you the opportunity to appoint a new secretary to accomplish the goals you set for the rest of your administration."

Jim Sims, executive director of the pro-business Partnership for the West, called Norton's tenure "a very strong one."

"She was able to pursue a common-sense balance between more sensible development and environmental conservation and I think she did a great job of finding that balance along the way."

The department has fallen under a cloud in recent months, as an investigation into the practices of convicted Indian casino lobbyist Jack Abramoff touched on Norton's former deputy, J. Steven Griles and a former political aide of Norton's who helped Abramoff gain access to the department.

Norton said the investigation has had virtually no impact on operations at the department, and she is confident that decisions at the department were on the level.

In 2003, Norton signed a memorandum of understanding with then-Utah Gov. Mike Leavitt aimed at creating a process to convey roads across federal lands to Utah counties. However, the state's first application for a road proved embarrassingly incomplete and three other applications are still in the pipeline.

"I believe there are many roads in the West where everyone would agree that the road usage should continue and the roads were clearly established. Unfortunately, we have not been able to resolve those issues," Norton said. "We have seen some clarification of the issues even though we haven't seen specific roads resolved."

Also in 2003, the department issued new policy that would prevent the creation of new wilderness areas in the state, freezing the acreage at 3.2 million acres, eliminating from consideration 2.6 million acres of potential wilderness identified during a Clinton-era survey and nearly 6 million sought by environmental groups.

The agreement is being challenged in court.

She pulled the plug on a major Utah land swap after BLM whistleblowers identified it as a giveaway of federal land and resources - claims later verified by an investigation by the Inspector General.

gehrke@sltrib.com