A city in the valley peeks over the hills to fresh frontiers

As a babe in arms, young pioneer John W. Young entered the lonely Salt Lake valley in 1847 on a horse-drawn wagon. He left on a train three decades later after a Mormon city was built, and he lived long enough to be able to fly back on an airplane into a star-spangled metropolis.

History like John Young's is as thick as honey on this beehive of a valley, and it shapes much of what makes the Salt Lake valley one of the nation's new urban bright lights.

Son of Mormon leader Brigham Young, John Young was one of the first business entrepreneurs to start the recurring themes in the valley: importing outside money for major projects and the gradual accommodation of Mormons and ''gentiles'' into a once theocratic and now very American city.

This reporter traveled to Salt Lake valley as an outsider - flying over the same Emigration Canyon where his great-grandfather John Young had entered 135 years ago - to see where its future lay.

Just in the last decade, this oft-misunderstood city has been hit with job-seeking migrants, skiers, oil drillers, filmmakers, high-tech scientists, artists, miners, developers, and many more Mormons.

Three-quarters of Utah's 1.5 million people are packed into an 85-mile urban strip from Provo to Salt Lake City to Ogden, perched on a plateau between the dry Great Salt Lake valley and the Wasatch Mountains, similiar to Denver's Front Range setting.

The population of this city-state - of which members of the Church of Jesus Christ of Latter-day Saints (Mormon) still are in the majority - has doubled in the last 30 years, with half of that increase coming in the last 10 years.

Ideally positioned in the middle of the energy-rich West, the former ''city of saints'' is a land of high achievers and plain dealers, full of self-reliance left over from the days when the Mormons redeemed a hostile environment with irrigation and hard work. No longer a remote and reclusive province, the valley still retains the lost innocence of America, where people describe themselves as optimistic, down-to-earth, uncomplicated, and full of Western derring-do and conservatism. Industriousness has been a byword ever since Brigham Young tried to name the area Deseret, a word for the honey bee.

The economy's building blocks are still defense industries, mineral resources , and the Mormon church, but the skiing, health, and electronics industries are coming on strong. Defense might have played an even greater role if the MX missile system had been placed in Utah, but the church's recent opposition has all but shelved the idea.

The area's social cohesion and strong pro-family ethos are the legacy of a once-communal Mormon society. The below-average wages and above-average education levels make the area a lure for US firms seeking more productive workers and a pro-business climate (only 12 percent of the workers are unionized).

Salt Lake, however, still shows signs of isolation. A recently transplanted oil executive, for instance, was shocked to find companies using 1950s-model IBM equipment and decades-old accounting systems. Also, the trusting Mormon environment has made it vulnerable to get-rich-quick schemes, land scams, and pyramid marketing.

Never the self-sufficient, wilderness hermitage (''Land of Zion'') that the early Mormons wished, the valley has an economic life that today carries on the theme of dependency, even though a self-generating economy is now developing.

The pioneers' homogeneity broke down late in the last century, first with the arrival of the Union Pacific Railroad, and then silver miners and the Kennecott Copper Corporation. As early as the 1890s Salt Lake City proper took on a non-Mormon majority population, and the state elected the nation's first Jewish governor as far back as World War I.

The region's oldest carpetbagger - the federal government - still is its largest employer, with over 22,000 workers at Hill Air Force Base. And the related industries such as the Thiokol, Heracles, and Sperry corporations produce one-third of durable goods in the state. Gov. Scott Matheson hopes to balance that federal crutch with more private employment.

Many new businesses are bred in the prestigious University of Utah, which has also helped implant the title of Bionics Valley to Salt Lake by being an epicenter for bioengineering research in the health industry.

The largest population center between Canada and Phoenix, and between Denver and California, Salt Lake nonetheless still exhibits deep-seated rural attitudes. Developers complain that city planners react to, rather than act on, new growth. Polls show an above-average liking for growth. A state panel last year concluded that governments in Utah do not plan for growth, nor ensure it ''occurs in an orderly manner.''

''I can't see what's stopping us from being a Phoenix or Denver,'' says Henry O. Whiteside, a state planner. ''Planning is a dirty word around here.'' The Mormon church's property manager, J. Howard Dunn, also is worried. ''If it grows helter-skelter, we can have trouble. If we wanted it to slow down, I don't think we could.''

Growth has obviously been uneven. In the 1970s, Salt Lake City proper actually lost population, while nearby Sandy City grew 692 percent.

We are a valley with 45 units of government - the county, 10 cities, and dozens of school, sewage, mosquito districts,'' says University of Utah political professor J.D. Williams. In the past decade, three attempts to form a metropolitan government have failed.Attempts by Salt Lake City to annex new land has been stopped by incorporation of suburban towns. The one frontier left is westward into the arid valley. But that area could be lost to the formation of another city from the remaining unincorporated areas of the county. In May voters in this unincorporated area are to vote on whether to form a city tentatively called Lake Valley City, which would be Utah's largest city, with more than 200,000 people and about 200 square miles spread over a crazy-quilt pattern.

The valley's boom started in the 1960s, when political and church leaders saw many young people leaving the state to seek their fortunes. Gov. Calvin Rampton sent out teams of ''Rampton's Raiders'' to campaign around the US for new business to come to Utah.

Many expatriates have come home as the number of jobs grew 5 percent in the 1970s (now down to 2 percent in a recession). Home building has been almost triple the national average.

Some of Denver's bulging energy-related growth has spilled over the mountains to the Utah capital. And Western Airlines plans to make Salt Lake its hub of operations, landing the first wide-body jets in the city.

Utah, unlike Midwestern or Northeastern states, has few giants to shed from an industrial age. More than 1,000 workers have recently been laid off at the World War II-vintage plant of US Steel at Geneva. Kennecott Corporation, which runs the largest open-pit copper mine in the world just outside the city, has had tough times and large layoffs. But last year's sale of Kennecott to Standard Oil Company (Ohio) brought a $7 billion investment in new equipment to keep the company competitive for the late 1980s.

Strangely, the valley has one of the lowest per capita income figures in the United States - due less to the income than to the capita. Birthrates are double the national average, and five-child families are common. But incomes are rising , faster than the national average.

Equal to jobs in attractiveness, however, are the amenities, which can be sweet indeed. Mountainside living means having some of the finest powder skiing on one's doorstep, with a lake (albeit a salty one) down the highway, and wilderness just a hollow away. The dry climate and stark beauty come with four distinct seasons. Arts performances are in surplus and among the best in the country. Crime remains low, and curbside friendliness high.

Encircled by mountains, however, the valley suffers air inversions in winter. The brown haze just sits there. The state has changed its pro-growth tune from ''Any job, any place,'' and is now singing the praises of nonpolluting industries. Smog alerts are less common, however, now that industrial stacks have been forced to scrub out pollutants.

''We're down to the automobile,'' says Governor Matheson. ''It's harder for people to set restrictions on themselves than on industry.'' Three tries to pass tough vehicle pollution laws failed in the Legislature, and now steps are under way to use county property taxes to force car owners into keeping their exhausts cleaner.

Woes like air pollution are at least a sign of new private industry. Only within the last three years have jobs in private firms surpassed public employment.

Less dependency on Uncle Sam, however, does not mean less dependence on outside capital. ''The West is not owned by Western residents,'' states Governor Matheson. Much of the development of Utah's abundant resources comes from outside firms. The financial lift for a ski resort boom is mainly money from Texas, Colorado, Venezuela, and Mexico. A Saudi Arabian family has been an aggressive investor in city development. Even Taiwanese money is found in real estate.

''There really is no capital here,'' says noted developer Wally Wright. ''The large families eat up any savings, and the church takes off 10 percent of incomes for tithing. The government takes the rest of any money people can save.''

Still, local banks have nearly $8 billion in resources, and high loan-to-deposit ratios. The largest bank, First Security with over $3 billion in assets, is a stable force in the community, still remembered for keeping its doors open during the Great Depression. And the valley has one of ''the finest credit ratings in the country,'' according to Moody's Investors Service. Bonds are issued reluctantly, with the preference for a pay-as-you-go approach. (This may stem from a Mormon sanction against living in debt.)

The pro-business ethic of Mormons attracts many ''gentile'' business leaders. The real mixer of Mormon and non-Mormon business people has been the Rotary Club , which tries to keep an informal 50-50 balance in membership.

But ever since John Young began bringing New York financiers into the valley to help build the railroads and new companies, the church's role has not been a problem for business. (He even bought a New York newspaper to breed goodwill between Mormons and non-Mormons.)

''John Young was the precursor for bringing non-Mormons and Mormons together, '' says Leonard J. Arrington, the leading church historian.

The growing accommodation and vibrant mix of Mormon and non-Mormon has helped shaped both the valley's past and future. And as Salt Lake becomes more of a commercial hub of the West - like its sister city of Denver - it could become an all-American melting pot.