For the third time in two years, road graders are preparing to work on the Burr Trail.

U.S. District Senior Judge Aldon J. Anderson gave permission Monday afternoon for Garfield County to begin work immediately on a 14-mile stretch of the now-famous dirt road.Garfield County Commissioner Tom Hatch said Tuesday that 4-5 inches of snow fell Monday in Panguitch, the county seat, in the eastern section of the county. If enough also fell on the Burr Trail, graders could begin work within the next two weeks, he said.

Work will start "just as soon as we can get the contractor lined up and he can mobilize his equipment," he said. Moisture is needed because dry soil won't compact properly when the subgrade is constructed.

But Terri Martin, regional representative of the National Parks and Conservation Association, one of the plaintiff groups, said the battle may not be over.

"It's still our position that it would be unlawful for the BLM to allow the work to go ahead until it completes the NEPA process," she said. NEPA is the National Environmental Policy Act, under which an environmental assessment is being prepared about the project.

The agency is responsible for preventing undue damage on all its land, she said. "We may appear back in court over that issue," Martin told reporters.

The grading project is the first step toward the county's eventual paving of the entire 66 miles between Boulder, Garfield County, and Bullfrog, Kane County - with the exception of parts in Capitol Reef National Park and Glen Canyon National Recreation Area.

In February 1987, Garfield County awarded an $854,232 contract to Harper Excavating, Kearns, to grade and smooth the trail. The four environmental groups sued within days, halting the project before the graders could move.

After a lengthy trial, Anderson ruled in the county's favor in late November 1987. Graders began working in a wilderness study area before the environmentalists could appeal.

When Anderson realized the work was proceeding while an appeal was planned, he ordered a halt. The U.S. 10th Circuit Court of Appeals endorsed the halt.

Recently, the 10th Circuit upheld Anderson in most aspects of the case but said the BLM should prepare an environmental assessment on parts of the trail where wilderness study areas might be affected.

Following up on the circuit court's direction, Anderson held an hourlong hearing Monday and lifted his injunction for the 14-mile stretch.

In the hearing, Assistant U.S. Attorney Joseph Anderson quoted Bureau of Land Management expert David Everett as saying the roadwork contemplated - between a predominately clay section called the Blues and the western border of Capitol Reef National Park - "would not unduly or unnecessarily degrade either the North Escalante or the Steep Creek (wilderness) study areas." Only the western half of the road is to be graded and improved, under the Harper contract.

Work on stretches bordered by wilderness study areas won't proceed until the BLM contractor completes the assessment. The study, expected to be issued for public comment in three or four weeks, will cover the whole trail.

Ron Thompson, a St. George lawyer representing Garfield County, told Judge Anderson the county would not ask the court for permission to work beside the study areas before the BLM completes its report.

Wayne Petty, representing the four conservation groups, said he does not disagree with Everett's statements. But he added, "plaintiffs do not agree that the work can begin immediately" anywhere.

Under the Federal Land Policy and Management Act, he said, the government has a duty to make sure none of its land is subject to unnecessary degradation, even parcels not included in wilderness study areas.

"Well, I'll say the injunction should be lifted (in the section discussed) and Garfield may proceed with the work," Judge Anderson ruled.

He added these provision: The county can't work on any archaeological site discovered by the BLM until the agency acts to lessen the damage; the BLM must stake any such sites; roadwork can't proceed wherever the BLM has found threatened or endangered plant species.