On the road to the airport, beyond which looms the vast emptiness of the north Siberian plain, men operated heavy earth-moving equipment as the temperature held at 42 below zero.

Our guide, a Russian, laughed with a touch of bravado, "This is nothing! You got here after a real cold spell a few weeks ago." It gets really cold, Viktor Zhuravlyov said, at minus 58 Fahrenheit. Children do not go to school and cranes crowding the skyline become idle.

"Just think, up at the port of Tiksi it was 74 below yesterday," said Zhuravlyov inside a warm bus. Yes, you can walk around as much as you wish but "make sure you touch your cheeks and nostrils every few minutes" to make sure they don't go numb.

We knew the next day was colder when the triple-pane windows of our hotel iced on the inside. The floor attendant, an elderly woman layered in woolen tights, admonished, "It's minus-49, son, you'd better cover your face."

The most striking thing about this Siberian outpost, after its inhuman weather, is the feeble yet tenacious human response to it.

Each movement outdoors is a confrontation with a vast antagonistic force. The cold freezes the tears drawn from the eyes. Each breath freezes into a whisp of stars, joining the frozen fumes of exhaust to form an almost solid fog that shrouds the city through its -40 days. YAKUTSK IS the center of the Yakut Autonomous Soviet Socialist Republic, which is almost as big as Western Europe. It is known as Yakutia and contains some of the world's richest reserves of gold, diamonds, natural gas and coal.

Many geographic names in the region send a different sort of shiver through older-generation Russians. They remember the places as prison camps under Stalin, just as under the czars. There is Kolyma, in the northeast, or the diamond-mining centers of Mirnyy, to the east, and Udachnyy, at the Arctic Circle, or the gold-mining center around Aldan, to the south.

Nowadays, people are lured here by high wages and a sense of adventure, although the first seems to be the stronger. A bus driver, for instance, makes a salary of 870 rubles a month, or more than four times the average Soviet monthly pay. The monthly wage for the operator of heavy equipment is 1,000 rubles or more--about $1,400 at the official exchange rate.

Although figures on gold and diamond production are state secrets, Yakuti Deputy Premier Tomniat Sivcev made it clear that his province is the largest Soviet producer of both. According to western figures, the Soviets mine about 17 million carats of diamonds annually--more than South Africa. Next to South Africa, the Soviet Union is the largest gold producer.

Sivcev, an economist and native Yakuti whose first name means "unfreezable," was more specific about other mineral wealth. He said experts have confirmed reserves of 13 trillion cubic meters of natural gas in an area west of here. He said an open-pit mine at Neryungri, south of here, contains 400 million tons of high-quality coal.

Such figures help explain the investments poured into the province and its capital, which has grown from a population of 7,000 in 1918 to a smooth-functioning if unexciting city of 203,000.

In czarist days, Yakutia was populated by Yakuti tribes--nomadic, reindeer-hunting, fur-trapping people whose copper-colored skin and oval, high-cheeked faces suggest kinship with the Eskimos as well as the Mongols. Russians who lived here were missionaries, political exiles or adventurers.

Today, according to Yakutsk Mayor Vladislav Shamshin, ethnic Russians comprise roughly 50 percent of the province's 1 million population.

The city looks like a sprawling construction site, with contemporary stone buildings already outnumbering the weathered log and timber ones. The permafrost poses special problems, the mayor said, quadrupling normal construction costs.

The layer of earth frozen to a depth of 5,000 feet in winter thaws to a depth of six feet in summer. This plays tricks on regular buildings, which sag and sink during the thaw.

The new Yakutsk is a city on concrete stilts, sunk 15 to 20 feet into the ground. Multistory structures are set on top of them starting two to six feet above ground, to prevent the heat of the buildings from thawing the permafrost. THE PERMAFROST makes road building prohibitively expensive, so Yakutsk has no railway or highway links to the rest of the country.

Supplies come from a Trans-Siberian Railway station at Ositrova, where they are loaded on ships and barges for a 1,250-mile long journey down the Lena River. Some are sent during the summer via the Arctic port of Tiski and up the Lena River.

During the seven months of winter, heavy supply trucks ply the river's 10-foot layer of ice. Snow-removing equipment maintains these river roads, marked by fir trees on the shoulders.

Food stores here seemed adequately supplied with canned meat and vegetables, though fresh meat is rationed. One person is entitled to 4.5 pounds of fresh meat per month.

Yakutsk has three professional theaters and 28 libraries. The city university has 6,000 students. There is live jazz in the evening and many first-run Soviet films are in several movie theaters. One Moscow television channel is received via satellite, and Pravda and other papers are on sale a day or two late.

And yet, many use vodka and an even stronger local brew to fight the frozen fog, and rowdiness and drunkenness are problems acknowledged by the mayor.

Despite the hardships, it seems that living standards at least rival those of other Soviet regions. Vacations are 42 days instead of the 24 elsewhere in the country. Every other year, each resident gets a free air ticket to any point in the Soviet Union. Many are able to travel to Japan, at a subsidized price. An average worker here can buy an automobile within two years.

And yet, Yakutia remains the end of the line. People come for several years but plan to go home after saving enough money to start a new life.

A waitress from the Ukraine, who with her husband makes almost 1,500 rubles a month--a huge sum by Soviet standards--spoke wistfully about going back to Kiev.

"This is our fifth year," she said. "We thought we would go back this year, but then decided to stay until next. But this is our last year, I can assure you."

Because there are not enough technicians, the authorities each year assign fresh university graduates here for two or three years, in effect to pay for their free education.

Deputy Premier Sivcev conceded a "considerable turnover of manpower." Yet, he added, the population of Yakutia has been growing steadily and he expects it to increase by 35 percent by the end of the century.

"This is a land of unlimited possibilities, don't forget that," he said.