ALLEDONIA, OHIO -- Four miles inside the Earth and 600 feet below the surface, Jim Myers and Frank Keylor are caught in a free-fire zone in the war against air pollution.

They are coal miners -- good ones, by their bosses' account; productive veterans like most of their colleagues in the Ohio Valley Coal Co.'s Powhatan No. 6 mine. They know no other work.

Unfortunately for them, the coal they produce is high in sulfur content. When burned at a power plant to generate electricity, it emits more than twice as much sulfur dioxide into the atmosphere as the new Clean Air Act allows. When the new limits go into effect in 1995, the 437 jobs here and thousands more in the coal fields of Indiana, Ohio, West Virginia and Pennsylvania may be doomed as the electric utilities that burn high-sulfur coal switch to other fuels.

"Doesn't look too good, does it?" said Keylor, 39, who has worked in this mine for 18 years. "By the time it shuts down, I'll be more than 40 years old. Who'll hire me?"

"I don't see what they expect us to do," said Myers, 46. "Crawl in a hole?" Myers, who served two tours of duty as a Marine in Vietnam, said, "We paid our dues. Now they just write us off."

Mining coal is grueling, sometimes dangerous work, but in a union mine like Powhatan No. 6, it pays about $17 an hour, plus overtime and health care benefits. In the economically depressed Ohio Valley, it's good duty. The miners here seem dazed by the idea that their jobs may be snatched away from them by forces they cannot control and for reasons they do not understand.

What's the point of sending troops to protect oil resources in the Persian Gulf, they ask, when domestic coal is cheap and plentiful? How can anyone take seriously the retraining money provided by the new law when there are no jobs in the Ohio Valley to train them for, and nobody to buy their houses if they move? Why is the federal government spending tens of millions of dollars on research to find ways to burn coal more cleanly when the research won't be completed by the time the 1995 deadline shuts down the mines? Why wouldn't those young congressional staff members talk to them when they went to Washington to plead their case?

"Their attitude in Washington is, 'Just shut it down,' " said Greg Smith. "They really think a group of blue-collar workers like this can be retrained and move around. A guy at the Labor Department told me, 'Too bad, there are no more lifetime jobs.' Our people are good, hard workers, but they can't be retrained. A lot of them didn't even finish school."

"In Washington they think we're expendable," said Larry Vucelich, president of the United Mine Workers local at the mine. "But there's a domino effect on the community" where the miners live and spend their money, providing jobs for others. Powhatan No. 6 is about 20 miles southwest of Wheeling, W.Va., in an area long mired in an economic slump.

Vucelich said his son in the Marine Corps is going to Saudi Arabia next month. "We're going to lose a bunch of boys over there, for the oil. We've got more coal here in Ohio than they have oil over there," he said.

"They say we have to be competitive in a world market," said miner Bob Houston, vice president of the UMW local. "Are we going to get up in the morning and do group exercises and eat rice and live in cubicles" like the Japanese?

In fact, economic competitiveness is not the mine's chief problem, according to Robert E. Murray, owner and president of Ohio Valley Coal. Aided by a $17 million "longwall" unit that he acquired last January, Powhatan set a world production record for an underground mine in October, Murray said.

"That shows you the quality of the work force," said mine manager Maynard St. John. "We just installed the longwall in January, and they set a record with it in October." A longwall is a complex machine that extracts coal from pillars within a mine that otherwise would have to be left in place to keep the mine from caving in.

"I've got the cheapest BTUs in the country," Murray said, referring to the heat-potential measurement British Thermal Units, because of the productivity of the mine, one of the largest underground mines in the United States. "That's the tragedy of it. These are the best workers in the country. All they want is to work in safety and dignity."

Murray, who has spent his life in the coal business, appears truly outraged by the acid-rain provisions of the Clean Air Act. His conversation keeps returning to what he calls a "criminal fraud" perpetrated by "a terrible government and a terrible president."

However, Murray said, he knows it's futile to keep lobbying against a measure already signed into law. He said he knows the debate in Washington is over, the meeting has ended and the briefcases are snapped shut, and now he has to live with the consequences.

That means trying to find ways to keep selling coal from Powhatan No. 6, in an uphill struggle to save his business and the miners' jobs. "This mine will be closed in January 1995 if I can't find markets," he said.

His most urgent task, he said, is trying to persuade his biggest single customer, Cleveland Electric Illuminating Co., to install sulfur-removing "scrubbers" on its power plants so it can keep burning high-sulfur coal.

In common with electric utilities throughout the Midwest, Cleveland Electric has to decide within the next year or so how to meet the clean-air standards that take effect Jan. 1, 1995, limiting sulfur dioxide emissions to 2.5 pounds per million BTU. Coal from Murray's mine emits 6.75 pounds.

"I don't see why they can't just make the utilities put scrubbers on and use this resource," Keylor said.

But for a utility, owned by shareholders seeking profits but required by state regulators to keep electricity rates as low as possible, development of a Clean Air Act compliance plan is a complex process.

The scrubbers that would make it possible to keep burning Ohio and Indiana high-sulfur coal are expensive -- at least $125 million each, according to one utility executive. But conversion to low-sulfur coal is expensive too: It costs more to buy, generates less electricity per ton, and requires installation of new equipment at the power plants.

Murry said he made a presentation to Cleveland Electric executives showing that their total cost, including freight, for low-sulfur coal would be $54.09 a ton, while the cost of his coal, including disposal of sludge from the scrubbers, would be $32.22.

He said he argued that the difference would make up for the cost of the scrubbers. But the Cleveland Electric officials, he said, told him they would not buy scrubbers because Ohio law allows them to pass on to their customers the higher cost of low-sulfur coal but not the capital investment represented by the scrubbers.

Cleveland Electric spokesman Mike Lumpe said "we honestly don't know yet" what the compliance plan will involve. "We do keep the jobs in mind, as well as the overall economy of our service territory and the state."