On a tiny cove nestled at the foot of rugged coastal mountains, more than 5,000 illiterate laborers are working on one of the world's largest atomic power projects.

By the mid-1980s, the three nuclear power stations currently in various stages of construction here will be supplying 3.2 million kilowatts of electricity to the booming cities of Sao Paulo and Rio de Janeiro.

Only a decade ago, sophisticated atomic power plants like these existed only in the United States and other major industrial countries. Not a single nuclear power station was operating in any of the developing nations of Asia, Africa or Latin America.

Today, atomic reactors are generating electricity in Argentina, Pakistan, India, South Korea and Taiwan. A half-dozen other developing countries have their first nuclear power plant on the way.

While many of these countries regard atomic power as an essential part of ambitious efforts to industrialize, building and operating nuclear facilities pose unforeseen and potentially serious problems for virtually all developing nations.

"The first atomic power station is a traumatic experience for most developing countries," observed a top official of the International Atomic Energy Agency.

Most of the concern in the United States about the nuclear power programs of these countries has centered on fears that some of them are secretly seeking to assemble atomic arsenals.

"Listen, I know the question people are after," said Dr. A.J.A. Roux, president of South Africa's Atomic Energy Board. "They want to know: Aren't we going to build nuclear weapons?"

The question is both a legitimate and, in some cases, a profoundly disturbing one. The Carter administration understandably has made halting the spread of nuclear weapons to the developing countries one of its major policy goals.

While India alone among developing nations has staged an atomic test, many experts feel that other developing countries will almost inevitably try to join the nuclear club before the end of the century.

But beyond weapons proliferation, there are equally urgent questions that should be asked about the spread of atomic power.

Can a developing nation -- with never enough trained manpower and a labor force not used to building this kind of sophisticated plant -- construct and operate a nuclear power station safely?

During a six-week tour of nuclear facilities in Brazil, Argentina, South Africa, Iran, India and South Korea, it became evident that atomic power is a more worrisome undertaking in most developing countries than in the United States.

"By definition, the risk of an accident has to be higher," said an International Atomic Energy Agency safety inspector who has visited a number of these nations.

So what business do these developing countries have with nuclear energy?

Do they really need it?

Can they handle it?

Are a lot of people going to die from it?

Should we be trying to stop it?

Most developing countries come well-armed with answers to the first question.

In South Korea, which has virtually no indigenous energy resources, officials argue that a large nuclear program is the only way they can hope to meet the soaring electricity demands of a rapidly expanding economy.

"We've almost exhausted our hydroelectric potential. We don't produce any thermal coal. Oil burning is too expensive -- completely out of the question," said Bong Suh Lee, assistant minister for planning in Korea's Ministry of Energy Resources.

Korea plans to build 43 atomic power plants which will generate 60 percent of its total electricity by the year 2000 -- a program that may make it more reliant on nuclear energy than any Western country.

But big nuclear programs cost big money. Korea's atomic plans may well cost it more than $70 billion by the end of the century. Brazil will probably wind up spending over $12 billion in the next 10 years -- including $2 billion to acquire "sensitive" uranium enrichment and plutonium reprocessing technologies that would give it a definite weapons capability.

But the spread of highly complex atomic power stations to countries that in some cases freely concede they are backward, technologically and industrially, seems certain to make the world a more dangerous place in the years ahead.

Most developing nations embark on nuclear power programs without really grasping that far more stringent standards are required for an atomic power plant than for anything they have ever dealt with before.

Pedro Freitas, a 39-year-old Brazilian mechanical engineer sent for training in West Germany, reported home in amazement that "the Germans have a veritable obsession with security." Echoed Antonio Fontenele, 26, an electrical engineer. "Here, in a nuclear reactor, redundancy is taken to the extreme."

Few developing countries, moreever, initially set up strong, independent regulatory agencies to make sure that their nuclear power plants are constructed safely.

Here at Angra dos Reis, the Brazilian contractor building the second of three atomic power stations on the site began draining the ground water despite protests by Westinghouse that this would jeopardize the stability of the first nuclear plant.

Brazil's nuclear energy commission took no action until the turbine hall of the Westinghouse plant began sliding down the slope toward the sea.

Beyond the normal problems inherent in building a nuclear plant, cyclones, tidal waves, earthquakes and extreme tropical heat are a few of the additional difficulties that geography seems to impose in unfair proportion on developing countries.

Not all developing nations appear to have given adequate consideration to some of the more frightening possibilities.

In designing two power stations now nearing completion at Kalpakkam on India's southeast coast, planners casually brushed aside any threat from the devastating cyclones that sweep across the Bay of Bengal.

"Cyclones follow a very predictable trajectory," an Indian nuclear official declared confidently. "Almost invariably, they hit one of four places very precisely."

Last year, as engineers huddled on the wind-swept jetty of the Kalpakkam plant waitting nervously for a cyclone that forecasters predicted would hit them dead on, they realized that relying on conventional wisdom about the weather is hardly sufficient when a nuclear accident is at stake.

"That cyclone was a real eyeopener," an engineer at the Kalpakkham station said. While the full force of the cyclone did not strike the plat, a task force was hastily set up in the wake of the incident to ensure that contaminated water from the spent fuel storage pool could not be swept into the sea in any future storm.

The possibility of terrorist attacks -- and regional wars -- also poses special problems for nuclear safety officials in most developing countries.

In 1971, Indian officials -- fearful that Pakistan would try early in their war to preempt any Indian move to assemble nuclear weapons -- set up an elaborate sea-and-air defense around the Bhabha Atomic Research Center ouside Bombay.

"We were all mighty worried," an official at the Bhabha center said.

In South Korea, where attack by the North is regarded as a constant possibility, a decision has been made to locate all power stations now planned for that country below the 36th Parallel, far from the border. The first operating atomic plant at Kori, on the southeastern coast, is protected by antifrogman nets and Falcon ground-to-air missile batteries.

But officials at the Korean Atomic Energy Research Institute on the outskirts of Seoul worry privately about what to do with the enriched uranium fuel in their two research reactors if North Korean troops should pour across the demilitarized zone only 25 miles away.

If Seoul were quickly overrun, these officials fear that if and when the South finally forced the North Keorean troops out again, they might blow up the research reactor with conventional explosives -- scattering highly radioactive wastes over a large area.

KAERI officials plan in case of war to take the irradiated fuel from the research reactors with them as they retreat south, but say present evacuation procedures would take several days.

"We've decided, though, that we just can't leave it here under any circumstances," an official of KAERI said grimly. "I'll carry the fuel rods by hand if necessary" -- an act that would certainly mean his life.

While few potential situations are as dramatic as that, there are indications that workers in atomic facilities in some developing countries run a greater risk of being exposed to high doses of radiation than nuclear workers in the industrial countries.

These reports are particularly difficult to pin down, because officials in developing countries are hypersensitive to the suggestion that they cannot handle nuclear energy safely.

But in India, which has been involved with nuclear energy longer than any other developing country, there is strong evidence that hundreds of workers have been permitted to exceed the maximum "safe" limit of radiation exposure.

Three hundred workers at the Tarapur atomic power station alone have been exposed during the past four years to annual radiation doses exceeding the standard limit of 5 rems (roentgen equivalent, man) per year. according to the annual exposure recording to the annual exposure reports of the health physics division of the Department of Atomic Energy.

Beyond that, the publication Business India in a recent well-documented report said the Indian Atomic Energy Commission was bringing 2,000 to 3,000 outside employes into the Tarapur plant each year "so as not to overexpose" even more of the operating personnel.

It is a common practice at Tarapur, the report said, for an outside maintenance worker to rush into an area holding a wrench in one hand and a pencil dosimeter in the other, turn a nut two or three rotations, and rush out.

"The problem is that a country like India has such a need for the power, that it is extremely difficult to shut down the nuclear plant for repairs," an IAEA safety inspector said.

The result, he said, is that "India, in maintenance of these plants, has dosed a lot of people. They won't get sick in the next six or seven years, and maybe never. But in the long term, who knows?"

An even greater safety problem for the future lies in the determination of India and other developing countries to build plutonium reprocessing facilities, and ultimately fast-breeder reactors.

Department of Atomic Energy officials scoffed at a published photograph of a "victim" of the Trombey reprocessing plant which appeared to show his skin peeling off, but sources conceded that both plants have had a "problem" with radiation leakage.

While many Americans feel that developing countries simply are not ready for these dangerous technologies, the irony is that most were started down the nuclear path by the United States.

President Eisenhower's Atoms for Peace program, launched exactly 25 years ago, spread nuclear research reactors throughout the developing world, and persuaded many countries that atomic power was the wave of the future.

"A lot of these programs that we are worrying about got a big charge from this naive notion that nuclear power was a panacea," a nuclear policy adviser to the Carter administration said.

Naive or not, that notion is firmly implanted in a number of developing countries. While the Carter administration may be succeeding in temporarily delaying the dissemination of "sensitive" nuclear technologies, the more advanced developing countries are determined not to be denied.

The firm commitment of countries like Brazil and South Korea -- and the sophisticated research facilities of India, South Africa and Argentina -- make it clear that it's too late to halt the spread of nuclear energy.

The only question now, it would seem, is how to manage and minimize the dangers of living in a nuclear world.

NEXT: The First Step