He is a solidly built man of 53 with flecks of gray in his well-trimmed mustache. He wears blue jeans and a patterned shirt and on his feet are a pair of smooth, brown work boots. In his hand, he cradles a green woolen cap.

He left El Salvador eight months ago and the images of the violence are etched in his memory. It was a cousin, pulled from his home one night by what the man believes were military troops. The cousin was taken outside and shot dead in front of his family.

The man shakes his head. He was unable to find work in El Salvador, unable to move freely on streets at night, and so he came to the United States. He does not want his name used, fearing that his family back home will be harmed if Salvadoran authorities see him quoted. His wife is ailing and he misses his children. He had hoped to return later this spring to be with them, but they have warned him that conditions are worse than ever. He says he may be forced to stay here indefinitely.

The man lives in an apartment with two other Salvadoran men, one 22, the other 18. Together they work at a church here. Only one has papers making his stay in the United States legal. Once strangers, the three are now members of a large and growing community of Salvadoran refugees in the United States, and part of a gathering storm of controversy over the Reagan administration's handling of the war there.

No one is certain how many Salvadorans are here, although estimates range from 60,000 to several hundred thousand. Many exhausted their savings to come here and, lacking proper documentation, entered illegally. Many sought political asylum without success, thousands more await a ruling on their requests, still more thousands--10,473 at a cost of more than $300 each in fiscal year 1981--have been shipped back by U.S. authorities, despite protests that they will be killed upon their return.

It is their fear of retribution that keeps the Salvadorans here and which, say lawyers working in their behalf, should make them eligible for asylum. The State and Justice departments, citing the law, say the Salvadorans cannot qualify for political asylum unless they can prove they will be persecuted at home because of "race, religion, nationality, membership of a particular social group or political opinion."

Fear of the widespread and indiscriminate violence there is not enough to protect them. The government says they are simply economic refugees. A lawyer working with refugees scoffs at that. "None has come just for a job," she said.

An extensive and increasingly militant national network of support for the refugees exists. Lawyers, ministers, church groups, social workers and private citizens are providing aid and comfort, sometimes in open violation of U.S. law, to the victims of war who are officially unwelcome in this country.

Residents of the Southwest, directly exposed to the plight of these refugees, have become increasingly bold in efforts to thwart the government's attempt to round up Salvadorans and ship them home.

The most dramatic example is a modern-day underground railroad that has been operating since last June. Centered in southern Arizona, this network stretches deep into Mexico with links to many major cities in the United States with large Salvadoran communities, such as Los Angeles, San Francisco and Las Vegas.

This underground railroad provides Salvadorans safe passage through Mexico, help in crossing the U.S.-Mexican border and food, lodging and transportation once the refugees are here. One of the persons involved describes its growth as "organic."

So far, little has been reported about this underground railroad. But because of recent crackdowns, organizers are considering whether to reveal their efforts to the public. They hope that in doing so they will demonstrate to the Reagan administration the ends to which ordinary citizens are willing to go to protest current U.S. policy.

An example of the growing militance of the above-ground support system for Salvadorans will occur March 24, the second anniversary of the slaying of Archbishop Oscar Romero in El Salvador, when churches in several major cities will establish themselves as sanctuaries for Central American refugees.

The sanctuary effort, a partly symbolic act to pressure the administration to change its treatment of the refugees, has been organized by the Tucson Ecumenical Council.

In the meantime, lawyers and legal aid groups are continuing case-by-case efforts to protect the rights of the Salvadoran refugees by seeking political asylum for those facing deportation. More than 7,000 asylum requests are pending before the Immigration and Naturalization Service and the State Department (which gives an advisory opinion in each case).

In the last fiscal year, only 156 cases were acted upon and only two refugees were granted asylum, according to an INS spokesman.

That record has brought the United States unprecedented criticism.

A recent report by the staff of the United Nations High Commission for Refugees said the United States, by insisting on returning the Salvadorans rather than being more generous in granting asylum, is failing to meet its obligations to these refugees, apparently the first time this country has been so challenged for its handling of refugees.

The Los Angeles Times reported recently that the State Department has liberalized its Salvadoran policy by recommending more grants of asylum, but State Department officials refused to confirm that.

Nonetheless, the strategy of the legal and religious network now helping the refugees seems to be to continue to clog the asylum pipeline. This has the practical effect of stretching the time it takes to resolve the cases, thereby making it possible for the Salvadorans to stay for perhaps two years or more.

As the government tries to clean out that pipeline, the refugees' supporters hope to force a policy change which will make it possible for some sort of blanket grant of asylum to be given.

On March 5, the National Center for Immigration Rights in Los Angeles filed a class action suit in federal district court, charging that immigration officials are illegally forcing Salvadorans to return home, are failing to apprise them of their rights and seeking asylum for the refugees while the war at home continues.

There are related efforts to pressure the Reagan administration to declare "voluntary extended departure" status for the Salvadorans, a step short of asylum but one that would prevent immigration officials from sending Salvadorans home until the war has cooled.

In recent years, such status has been given to refugees fleeing terror in Lebanon, Ethiopia, Uganda and Nicaragua, during the closing months of the revolution there.

The administration has the authority to make such a declaration, but there are efforts in Congress to get that body on record in support of such a move.

Meanwhile, what was once a trickle of refugees has become a steady stream.

'Impossible to Live'

G. is a soft-featured man of 30 whose efforts to grow a wispy beard are thwarted by his baby-smooth skin. His father once drove a taxi in El Salvador and his mother sold clothes. But his father's taxi was destroyed in the fighting and his parents are now living on their savings instead of working.

A little more than a year ago he decided to come to the United States. He wrote to a friend in Houston to say he was coming, managed to get a passport from his government, got on a bus and spent nearly four days making the long trip north to the border.

From there he telephoned his friend and arranged a meeting on the U.S. side of the border. Then he swam the Rio Grande River, into south Texas.

G. worked off and on and lived in the underground until February, when immigration agents picked him up at a driver's license office in Houston. His bond was set at $3,000, the norm for most Salvadorans and three times the average for Mexicans, and a deportation hearing was set. One of the legal aid groups in town was contacted and G. obtained representation.

At his recent hearing he filed for political asylum and now he must begin his long period of uncertainty, fearing that he might have to go back. "It is impossible to live there," he said.

Secretary of State Alexander M. Haig Jr., in defending administration policy before Congress recently, warned of the consequences of a leftist victory in El Salvador.

"Just think what the level of illegal Central American immigration in the United States might be if the radicalization of this hemisphere continues with the only alternative a totalitarian model," he said. "Why, it will make the Cuban influx look like child's play."

But the opponents of administration policy charge that U.S. military support of the government in El Salvador has helped raise the level of terror there and thus has contributed to the flow of refugees to this country. The staff of the U.N. High Commissioner on Refugees said there was "a direct causal relationship" between the fighting and the movement of refugees into the United States.

Figures provided by Border Patrol agents paint a confusing picture of whether the escalation of fighting in recent months has resulted in more refugees, with increases in certain areas and decreases in others.

But the legal aid network aiding Salvadorans believes there are more now. "There has been a noticeable increase," said Daniel Harms of the Center for Immigration in Houston.

A man in Tucson who is working with refugees believes the relationship between the fighting and the flow of refugees is so strong that he can almost predict where the next group will be from by the location of the worst violence in El Salvador. "There is an eight-to-10 day lag" between reports of the fighting and the arrival of refugees, he said.

He also has noticed a change in the composition of the refugees arriving, with more women and children than ever before. A Border Patrol agent in south Texas reported last week that whole Salvadoran families are coming across together, while in the Tucson area, church workers say family members often arrive one after another.

"It's like a bomb was dropped over El Salvador, scattering pieces of families all over," said Timothy Nonn of the Tucson Ecumenical Council.

Until recently, all were middle or lower-middle class, many of whom had paid $1,500 or more to a smuggler, or "coyote," to get them safely to some U.S. city. Lately, however, the first peasants, or campesinos, have begun to arrive, a sign interpreted by refugee workers of the desperate conditions that now exist in El Salvador.

Uniformly, the refugees come with tales of horror, of family members or neighbors killed, of attempted recruitment by the guerrillas, of threats if they don't cooperate, of beatings and harassment. "The Salvadorans talk all the time about 'they.' 'They' broke into the house, 'they' burned the bus, 'they' killed someone," said Harms.

But when pressed, they often attribute the killings to the military forces, rather than the guerrillas. "The guerrillas don't hurt poor people," said a refugee in Houston.

Caught in the Middle

But these refugees mostly feel caught in the middle. While they attributed the killings to the military, they fear life under guerrilla rule would be as bad, for they assume the guerrillas will turn out to be communists.

"Cuba is helping the guerrillas," said the 53-year-old refugee in Houston. "The same thing will happen as in Nicaragua. The communists will dominate and won't let people leave their towns."

The refugees are well-informed about events back home and have strong, if pessimistic, opinions about the situation there. They have little hope for the elections scheduled for March 28, and only slightly more hope that the war can be brought to an end easily. "No one knows the future," G. said.

Once in the United States, the refugees stay in close touch with families back home through letters and phone calls. They listen to Spanish-language radio and television stations that blanket the Southwest and California and keep up with Salvadoran newspapers mailed from home.

The war is a constant topic of conversations, and new arrivals bring the latest news.

"The best place to find out about what's going on down there is here," said a man in Tucson.

The Salvadoran refugees have come prepared for a long stay in the United States, but most want to return to El Salvador. "They find the United States cold, harsh, unfriendly," said Eudelia Talamantes, a Houston lawyer who specializes in immigration rights.

They cluster with one another, seeking comfort and solace. By now there are substantial Salvadoran communities in Los Angeles, San Francisco, Las Vegas, Houston, New York and Washington, and the Salvadorans are effective at absorbing newcomers.

Recently 80 refugees landed at a church in Los Angeles, and within three days, all but six had found homes.

The Los Angeles community is by far the largest, but there are reports of a secondary migration under way between Los Angeles and Houston, where there is said to be work available. As these communities flourish, a separate culture develops.

In Houston, Salvadoran restaurants have popped up in the past 18 months, and there are now regular announcements aimed at the Salvadoran communities on the Spanish-language radio station.

On the advice of a Salvadoran woman working for him, Guadelupe Galindo, of Mexican background, converted his restaurant in Houston to Salvadoran, and by now 90 percent of his clientele is Salvadoran. "I can't complain about business, especially on weekends," he said. He is sponsoring a dance with two Salvadoran bands on the eve of the March 28 elections.

Many refugees remain undetected by immigration authorities for months or perhaps years, but increasingly the activities of INS have raised tensions. In the suit filed recently by the National Center for Immigration Rights, lawyers charged that INS officials have deliberately failed to inform the Salvadorans of their rights to deportation hearings and to apply for political asylum. Instead, the suit alleges, INS agents have coerced the Salvadorans into signing forms that call for voluntary returns to El Salvador.

In fiscal 1981, for example, INS apprehended 15,000 Salvadorans and of the 10,000 that were sent home, the overwhelming majority returned "voluntarily."

The legal aid groups are seeking to supply as many Salvadorans as possible with advice, and some groups have come up with imaginative solutions.

The Valley Religious Task Force on El Salvador in Phoenix has worked out an arrangement with immigration officials to allow refugees to be released on their own recognizance if they agree to stay with a family in the area. In Tucson, the Manzo Area Council has been raising bail money for Salvadorans and has freed about 200 refugees.

In south Texas, a private law firm has become a central clearinghouse of legal advice and activism in support of the refugees.

But for each refugee helped, others are left to languish in one of various detention centers that dot the border. Major centers handling Salvadorans are at El Centro, Calif., and El Paso and Harlingen, Tex. The El Centro center has been a point of controversy for several months.

Camp Criticized

A staff member working for Sen. Dennis DeConcini (D-Ariz.) toured the facility and filed a 50-page report that sharply criticized conditions. The staffer reported seeing one man with an untreated compound fracture and that refugees were left out in the summer sun from early morning until early evening.

DeConcini sought a response from the Justice Department and last week Attorney General William French Smith sent back a 17-page refutation of the report, according to Robert Maynes, DeConcini's press secretary.

But DeConcini's staff remains skeptical and is trying to decide the next move. "If they've gotten everything straightened out, terrific," Maynes said. "I've got my doubts."

The afternoon shadows were beginning to lengthen as the three refugees at the church in Houston continued to spill out their stories. They spoke only in Spanish, but at one point, with the interpreter otherwise occupied, one of them rose emotionally to answer a question about conditions back home.

He raised his arms as if to grip a rifle, pointed it and pretended to shoot. "No good," he said in English. No good. It was all he had to say.