A 1964 law setting aside millions of acres of "wilderness areas" is providing an opening for mining companies to test drill for minerals in federally protected forests and wildlife areas.

The American Smelting and Refining CO. (ASARCO) has begun exploratory drilling for silver and copper inside the Cabinet Mountains Wilderness Area, the first mining firm to test drill in the U.S. Forest Service's northern region that covers most of the Pacific Northwest.

The 94,272-acre Cabinet Mountains Wilderness is one of 187 designated wilderness areas in the United States.

The drilling for silver and copper in the Cabinet area, along with other regional developments, has chilled conservationists.

A provision in the Wilderness Act of 1964 gives mining companies the right to stake and explore claims in designated wilderness areas up to 1984. After that, said Bill O'Brien, a forester based in the Kootenai National Forest office here, only claims that have been explored and documented as having commercial quantities of minerals can be mined.

John Balla, ASARCO's manager for northwest exploration, said the company has 140 claims of about 20 acres each, all in the wilderness area near 7,018-foot Chicago Peak.

"We have to make a valid discovery before Dec. 31, 1983," he said, for commercial mining to commence.

That is just the beginning. Troy District Ranger Bjorn Dahl of the Forest Service said more than 3,000 mining claims, old and new, have been filed in his district alone. Oil and gas lease applications for 493,000 acres in three northern Montana wilderness areas have been received in the Forest Service leasing division in Missoula.

Activist groups are sprouting. The Libby Rod and Gun Club has brought suit against a proposed hydroelectric dam on the Kootenai River that backs into Canada, the Cabinet Resource Group is dogging an ASARCO copper-silver mine 25 miles from here at Mount Vernon and the Northern Sanders County Citizens Groups has made unsuccessful attempts to stop the exploratory drilling in the Cabinet Mountains Wilderness Area.

On the other side, the recently organized Northwest Energy Employment and Development citizens' group (NEED) is promoting two proposed hydroelectric power dams and the Mount Vernon mine to bring more money and jobs to the area.

The most recent group is GREED -- Get Rich Exploiting Earth's Development.

Mining in a wilderness area is a last resort, Balla said. The company has a right to extract core samples from the wilderness but the Forest Service can impose costly restrictions. Because no roads can be built into the wilderness for exploration, ASARCO must haul drilling equipment to the site by helicopter.

If ASARCO finds an ore deposit large enough to make it economical to mine, the firm conceivably could be permitted to build a road and mine within the wilderness boundary, Andy Anding, acting Cabinet District ranger, said.

In February, ASARCO filed a plan with the Forest Service for mineral exploration of the wilderness. The Forest Service responded with a 117-page environmental assessment (an analysis to determine whether an environmental impact statement is necessary) that said the exploration would not significantly disturb the area.

The U.S. Fish and Wildlife Service, as required under the Endangered Species Act, studied it and concluded that the area's grizzly bears, listed under the act as "threatened," would not suffer significantly.

The Western Sanders County Involved Citizens appealed the Cabinet District approval, but Northern Region forester Tom Costin in Missoula upheld the district.

The group's attorney, Peter Wagstaff of Coeur d'Alene, Idaho, said he has appealed to Forest Service officials in Washington, D.C., but will not go into federal court. "This isn't the time," he said.

Rocky Rockwell, district forest resource assistant, said, "We all have opinions about what they should or shouldn't be doing in the wilderness, but that's immaterial. The law spells out pretty much what they can do."

Besides hauling equipment to the wilderness drilling sites by helicopter, ASARCO is required to put its equipment on 9-by-9-foot wooden platforms to minimize disturbance to land on a 30-foot square drilling site.

The Montana Department of Natural Resources has given temporary permission to pump up to 7,500 gallons of water a day from nearby Cliff Lake to help cool the diamond drill bits.

Sludge from the drilling is supposed to be settled in water tanks -- actually livestock water troughs -- and hauled out of the wilderness for disposal. "All we are going to leave there is a hole that will be covered up, nothing else that would degrade the area," Balla said.

The holes, he said, will be up to 1,400 feet deep, adding that it costs ASARCO about $40 a foot to drill. The drills bore about 80 feet a day in two 10-hour shifts. The drilling will continue after winter until the ore deposit can be analyzed, Balla said.

While the ASARCO test drilling in the Cabinet Mountains Wilderness Area proceeds, environmental groups largely have adopted a wait-and-see attitude.

"This isn't big enough potatoes yet," said Bob Springer, spokesman for the Sanders County citizens group. "But anyone in the United States who has a concern for wilderness is going to have to take a look at this."

Bill Cunningham, Montana representative for The Wilderness Society, said, "We recognize that mining was one of the many compromises needed in the 8 1/2 years it took to pass the Wilderness Act. We feel under certain circumstances that mining done with minimum access and very strict reclamation standards can be compatible with wilderness."

"Our concerns don't just stem from the Wilderness Act," he said, "but for the physical land and wildlife in the area. We'd be concerned even if it wasn't wilderness."

Cunningham said the Wilderness Society has had no success in pressing the Forest Service to make an overall assessment of development in western Montana.

"I think it's essential that a regional environmental impact statement be made to look at the whole variety of major development occurring in the area," he said. "We can't continue to look at it piecemeal."

But Cunningham called the Fish and Wildlife Service's assumption that ASARCO drilling would not affect the grizzly population "a whitewash," claiming that input on occupied grizzly habitat and water quality problems "hasn't been adequately investigated."

Doug Scott, northwest representative for the Sierra Club, said the time is not ripe for the club's lawyers to intervene.

"At the proper moment in the application and approval process," he said, "we'll be ready on a moment's notice. Right now we're relying on the local folks."