This is a land of elemental beauty, where time and space disappear amid the mesas, and outcroppings of ageless rock dot the horizon. But here in the homeland of the Navajo Indian nation, a clock is ticking, a clock set by the laws of Washington. This week, the Bureau of Indian Affairs started it moving once again.

BIA announced last Monday that it would resume the controversial impoundment of Navajo livestock found grazing illegally on land now controlled by the Hopi Indian nation, whose reservation sits entirely within the huge Navajo reservation. It is the lastest development in a century-old dispute between the two tribes that is moving toward resolution, confrontation or both.

By Jan. 8, 1982, BIA must remove at least 1,500 Navajo sheep, or their equivalent, in order to bring the number of livestock down to what the arid grazing land can accomodate. The stock impoundment is part of the legal actions that eventually will force about 9,000 Navajos to leave their homeland for housing elsewhere, the result of congressional legislation aimed at settling the long dispute.

The Navajos call the relocation and the attendant harassment "the second long walk," in memory of the 8,000 members of their tribe rounded up by Col. Kit Carson in the 1960s and marched from Arizona into confinement in eastern New Mexico.

BIA began impounding livestock in April, but suspended its program on May 11 because of the bitter reaction from the Navajo leaders and the traditional Navajo people, whose only livelihood comes from their sheep and cattle.

Navajo tribal chairman Peter MacDonald is angry about the BIA's decision to resume impounding the stock, despite new assurances from the government that it will give ample waring to people whose stock will be taken and an agreement to reevaluate how many animals the land can hold.

"It is designed to reactivate fear and anxiety and emotional upheaval of people already subjected to unnecessary harrasment," MacDonald said in his office at tribal headquarters.

"the Hopis say they want range land," MacDonald added. "Our people say this is their homeland and is sacred land. There is no way you can partition Mecca."

But chairman of the Hopi tribe, Abbott Sekequaptewa, is just as unyielding. He pressured the Bia to resume the impoundment program and filed suit in federal district court seeking its continuation.

"We cannot put livestock out there without getting back into the situation [of overcrowding]," he said. "The BIA has to vigoriously reduce vigorously reduce livestock that are there."

The Navajo and Hopi tribes have been friendly enemies for centuries, long before white men ever came to this desolate corner of the Southwest. But this dispute grew directly out of a decision by President Chester A. Arthur, who designated a rectangle 70 miles long and 55 miles wide as a reservation for the Hopis. At the time, many Navajos lived in the designated area.

In 1962, a federal court ruled that a baseball-diamond-shaped area of roughly 640,000 acres immediately around the Hopi villiages was the exclusive domain of the Hopis, with the rest of the 2.4 million acres to be shared equally by the two tribes as a Join Use Area. The Hopis pressed for a clearer resolution of the territory, and in 1974 Congress approved legislation dividing the Joint Use Area evenly between the two tribes. It is because of that legislation that the Navajos living on the Hopi partition land have been ordered to move. About 100 Hopis living on Navajo partition land also must move.

Relocation of the families began several years ago. To date about 336 families have been relocated at government expense, including some who received new homes in Flagstaff and other nearby towns. Navajo leaders say the relocation of the families has slowed to a trickle, a fact contradicted by Leon Berger, executive director of the Relocation Commission.

Berger said 1,109 cetified applications are pending, and that at present 25 families are in the process of acquiring new housing and 32 families are seeking new homes.

But there is agreement that most of the families relocated so far were not living on the Hopi partition land at the time they applied for government assistance. Moving the rest of the families, may be more time-consuming and difficult, and there are pockets of resistance among many of the traditional Navajo people, who live in mud hogans with no plumbing or electricity, tending their livestock.

On April 18, the two tribes officially took possession of their shares of the former Joint Use Area, the development that triggered the original BIA impoundment program.Last month, Congress officially approved the relocation program, and as a result, all the Navajos now in the Hopi partition area are to be gone by July, 1986.

"Feelings have increased because the time is coming when the Navajo people have to be off those lands," said Pat Ragsdale, assistant BIA area director in Phoenix. Ragsdale is in charge of implementing the stock relocation program, and he has been the target of inflamed rhetoric from Navajo chairman MacDonald.

Both the Navajo and Hopi tribes are seeking compromise solutions to the land dispute.

MacDonald told the Republican Forum in Phoenix this week that he wants to buy the Hopi partition land, which he described as an "all-American" solution.He told the forum he would pay $75 million for the roughly one million acres, but said in an interview later the Navajo tribe would pay whatever was considered the fair market value.

"It doesn't make any difference how much money you offer, we don't want to sell the land," Sekaquaptewa said. "This land is a chosen land to which the Hopi people were brought by divine guidance."

The Hopis have offered their own land-exchange solution. They are willing to trade Hopi partition land around Big Mountain, the home of many of the most traditional of the Navajos and a center of resistance to the legislation, in return for 16 small parcels of land now held by the Navajos. The two tribes are in sharp disagreement over the progress of such negotiations.

Under legislative amendements approved in 1980, the Navajos are entitled to acquire 400,000 acres of land (250,000 acres from the government and 150,000 at their own expense) to provide alternative housing for the people forced to move from the Hopi lands. MacDonald's other proposal is to take 400,000 acres from the Hopis, thus reducing the number of Navajos who must move, but the Hopis oppose this as well.

BIA officials describe these land-exchange discussions as extremely fragile right now, and they have brought in a mediator to monitor any progress. Leon Berger of the Relocation Commission said he doubts that the 1968 relocation deadline can be met unless there is a speedy decision on acquisition of new acreage. The impoundment program makes that more difficult because it has heightened tensions within the Navajo nation, and Bia officals are hoping to avoid confrontation over the livestock issue, lest the land exchange talks collapse.

But MacDonald continues to take a hard line by urging his people to resist the new law. "It's out position that the legislation is wrong," he said. "How can you comply with a law that says," 'Prepare your own grave and sharpen the ax that will be used to cut your head?'"