Minor routines, long absent here, attest to war-wracked Chad's return to a tenuous tranquility. Two dozen poolside lunchers at the Hotel Tchadienne, for instance, found it not at all extraordinary to be watching the new lifeguard in an hour-long training session in preparation for expected swimmers--a routine that not long ago would have been considered a misplaced confidence in the future.

Today, six months after Hissene Habre, the victor in the latest round of the country's 17-year civil war, installed himself as president, most of Chad has begun to settle into the normality of peace.

"Water pressure is up, there is electricity 24 hours a day, and they're fixing the street lights," said a long-time American resident of Chad and former Peace Corps volunteer here about the simple signs that give him and his Chadian wife hope that the fighting has finally ended.

"This government inspires confidence," he said, declining to have his name used. But it is still unclear if the present calm is but another lull before a new round of carnage. In Chad's northwest Tibesti Mountains, Goukouni Oueddei, the deposed president chased out of Ndjamena by Habre's forces in June, is rebuilding his own private army with Libyan help at a town called Bardai, according to African diplomatic sources.

Libyan leader Muammar Qaddafi, whose soldiers have occupied the northern Chadian Aouzou Strip just north of Bardai for the past decade, has hinted that he is ready to become militarily involved in Chad as he did in 1980 and 1981 with an invasion and year-long military occupation in support of Goukouni.

Qaddafi is said also to have rounded up thousands of Chadians working in Libya and sent them to northern Chad to be trained as the core of a new army for Goukouni.

"We think they have about 6,000 men" undergoing training, said a senior Egyptian diplomat. The same diplomat and others, however, said that despite Qaddafi's blustering they doubt that he would want to invade Chad again.

"The last one cost him a lot in men and materiel," said a western military source, "and it was not popular at home." The moderate states of Egypt, Sudan, Saudi Arabia and Morocco, all close allies of the United States, have been some of Habre's staunchest backers against the Libyan-supported Goukouni. Indeed, both the United States and France, Chad's former colonial master, have been interested in shoring up this battered country as a buffer against Qaddafi's pan-Islamic expansionist dreams.

A western military source said that French military officers have indicated that France will assist Habre "with arms" if a Libyan-backed Goukouni-led force or the Libyans themselves again attack Habre as they did in late 1980, chasing him out of Ndjamena.

It was also learned that Habre's military officers repeatedly have asked U.S. diplomatic officials for assistance in arms and training.

The acting head of the U.S. Embassy in Ndjamena recently refused three requests to meet with a reporter, but an informed western military source said that U.S. diplomats have told Habre's officials that they will only supply humanitarian aid and agricultural development assistance. The U.S. Agency for International Development is in the process of reopening its mission here after hastily evacuating its staff during heavy fighting in Ndjamena almost three years ago.

One nongovernment development expert, with long experience in Chad, said that AID's reopening "comes from seeing that Habre's government is trying harder" than Goukouni's "faction-riddled government ever did."

Fighting first erupted in Chad, a poor, landlocked, semiarid country of 4 million in central Africa, in the mid-1960s when factions of northern Moslems attacked the government then controlled by the country's southern Christian blacks.

The northerners accused the southerners of not giving them an equal share in the running of Chad and of corruption and repression. The battles see-sawed across Chad until the southerners were decisively defeated in fierce fighting in Ndjamena in 1979. Then the 10 Moslem factions, five of which had private armies, formed a weak, uneasy coalition government.

In early 1980, Habre's highly disciplined forces took on all the Moslem factions in Goukouni's government and their allies, the southerners, in bloody fighting in Ndjamena. Nine months into the contest, Qaddafi intervened at Goukouni's invitation and the Libyans chased Habre out of Ndjamena west into neighboring Sudan. A year later, pressured by France and the United States and assured of a peace-keeping force from the Organization of African Unity, Goukouni asked the Libyans to withdraw. But after the Libyan withdrawal, Habre moved his forces out of Sudan and headed straight for Ndjamena.

Goukouni demanded that the OAU peace-keeping force fight Habre, but the Nigerian commander of the force insisted that that was not part of his mandate.

The force was about to be withdrawn after running out of funds in June when Habre attacked and easily captured Ndjamena form Goukouni's loosely disciplined troops. Goukouni escaped across the Chari River into Cameroon.

At the end of November, the OAU's second effort in four months to hold a summit in Libya broke down completely over which Chadian delegation should be seated, Goukouni's or Habre's.

In September, Habre defeated the last of Goukouni's supporters, Col. Abdelkader Kamougue, in southern Chad. In October, Habre formed his government, bringing 14 southerners into his 31-man Cabinet as a major reconciliation effort.

While the fighting has stopped for now, Chad still has numerous difficulties to overcome.

A major drought hit some areas and the inabliity to plant in others because of the fighting has spurred western nations to bring in emergency food shipments. Health services, housing, roads and water supplies have all severely deteriorated in the past 17 years. Only some of the schools in Ndjamena opened in November.

At a U.N.-sponsored conference on Chad in Geneva at the end of November, attended by virtually every international aid agency, more than $287 million was pledged to help the country recover.