While Democratic senators lay the Watergate over the confirmation moat for retired general Alexander M. Haig Jr., other Cabinet appointments are being greeted with a chorus of groans from other quarters.

Getting the loudest raspberry is the expected nomination as interior secretary of James G. Watt, a conservative whose job for the Mountain States Legal Foundation consists of trying to tear apart in court most of what environmentalists have spent years putting together.

American Indian groups were displeased as well -- the Bureau of Indian Affairs is under the jurisdiction of the interior secretary. Watt's legal foundation launched an attack on tribal sovereignty Nov. 19 in a brief filed with the U.S. Supreme Court in support of an oil company's lawsuit against the Jicarilla Apache tribe.

The Clary Institute, an Indian-owned management consulting firm in Washington, immediately fired off a letter to President-elect Ronald Reagan, reminding him that he is on the record as supporting tribal sovereignty. The institute also sought to job Reagan's memory on his statement that he believed in "consulting with tribes and their leaders . . . about appointments to federal government positions affecting Indians. . . ." The letter was endorsed this week by 176 tribal leaders attending a conference in San Diego. The BIA recognizes 499 tribes.

Environmentalist groups, universally dismayed at the prospect of Watt's appointment, meanwhile, were at loose ends in deciding what to do about it. While some vowed to battle his confirmation -- "There's no way we can't fight it," said a spokesman for one environmental organization -- others were looking farther down the line.

"Nobody deludes themselves that they'll keep him from getting the job," said one official -- and an attempt to do so, he indicated, could do more damage than good to the environmentalists' cause.