Juan Gomez says he remembers only that it was dawn and it was somewhere in the city when he stumbled out of the locked van in which he had been riding for four days and found his way to the apartment of cousins from his native El Salvador.

The dropoff place was one of four in Northwest Washington and Arlington where illegal aliens end their 5,500-mile trip from El Salvador to Washington. From there they disappear into the large El Salvadorean community, believed to number at least 10,000 aliens, that exists here virtually without trace in the public record.

Three weeks later Gomez, 24, was deported, and within five days he was back on the El Salvador trail, back on the bus to Tijuana in the van to Washington and with his cousins somewhere in Adams-Morgan.

It took him three months after his second trip here to land a construction job in Maryland that paid $120 a week. From that he was able to save $100 to send home to his parents and ll unemployed brothers and sisters in the small farming village of Chirilagua.

Juan Gomez is not his real name, but the story of his clandestine journey to Washington is repeated thousands of times each year by illegal aliens fleeing from one of the most impoverished and the smallest in the string of tiny countries that make up Central America.

For fees ranging from $300 to $1,500, a fortune in a country where the annual per capita income is $400, a growing number of Salvadoreans is heading north for the promise of a better life in Washington.

Many, like Gomez, plunge into debt or sell their farms for the 5,500-mile trip that leaves them deposited on dark Washington streets sometimes penniless and with little more than a hope of evading immigration authorities. In the past two years, Salvadoreans have accounted for 25 percent of all illegal aliens apprehended in Washington. The number in February alone was more than double that from all other Latin American countries.

"I couldn't make any money in El Salvador," Gomez said softly in Spanish as he sat in an immigration office last week awaiting his second deportation to Latin America in less than a year. "Word gets around about Washington."

The word about Washington that lures Salvadoreans is the chance of securing, with no questions asked, one of the thousands of low paying services jobs in the area and the prospect of living in a community that contains many of their fellow countrymen. Hispanic community leaders say there may be at least 20,000 Salvadoreans in the District alone and that half of them may have arrived in the country illegally.

A small wiry man dressed in beige wool pants and a T-shirt emblazoned with a shiny blue and silver astrological sign, Gomez was one of three Salvadorean aliens picked up last week in a raid on a crowded U Street NW apartment.

Through an interpreter he spoke haltingly about his route up while awaiting a 10-mile deportation hearing. Immigration officials said that although they believe Gomez falsified some details to protect his smuggler his story is typical.

No one in his family of 13 had a job, he said. Gomez said he went to a moneylender in his village who lent him $1,000. The moneylender told him to go to San Salvador, the country's teeming capital city, and see a Mexican know as "Escobar."

Escobar told Gomez that for the $1,000, he would arrange the trip.First, Gomez was told to take a bus to Guatemala and then to Tijuana, the tough Mexican city on the California border, where he was met by another Mexican called Caesar.

Caesar took Gomez to a "drop house", where Gomez joined nine other Salvadoreans to wait for the nightfall and trip across the Mexican border into the U.S.

Late that night Caesar led the group on an all-night walk across the border, skillfully weaving through the seismic sensors embedded in the ground that are supposed to detect foot traffic. "I was told it would be easy to cross," Gomez said "so I was not afraid." Other aliens said the walk across the border is regarded as a test of manhood.

At dawn the group was met by an American who was waiting in a gray pickup truck with a canvas cover. They were driven to a van where another American, the driver, was waiting. The group was then locked into the windowless van for a four-day, drive to Washington.

On arrival here, Gomez stayed with a "cousin" in an apartment in Adams-Morgan for a few days while he looked for work. It took him months to find a $120-a-week job as a construction worker in Maryland. "I had no address," he said. "I slept in various places, with friends."

Gomez said he was never asked for identification and was able to submerge himself in Washington's Spanish-speaking community with ease. Saturdays were the highlight of his week: there were Spanish-language movies at an Adams-Morgan theater, he said.

"Life is much better here," said Gomez. After his first apprehension he spent two nights in jail before being driven to Dulles International Airport for his flight back to El Salvador for $242, a trip paid for by the U.S. government. "I don't know what I'll do now," Gomez said.

"It's very likely he'll come back," said immigration agent William Crane. "Catching aliens a second time is common, but catching them a third time is considerably less common."

"Many smugglers work on a guaranteed delivery system," said agent William Selzer, a member of the newly formed anti-smuggling task force. "If people are deported and don't talk, the smugglers will guarantee redelivery."

The smugglers, some of whom have operated highly organized and extremely profitable rings for years, are as feared and as well-insulated from law enforcement officials as Mafia chieftains, Crane said.

"There are so many horror stories," Selzer said, of aliens locked in the trunks of cars or vans that have been abandoned on route in the broiling desert sun or the snowdrifts of the North.

Selzer said it is common for aliens to be packed into padlocked vehicles with little food or water.

"They come like less than animals, but they like it here because it is so much better than what they left," said Father Jose Alas, an exiled Salvadorean priest who has been in Washington for a year.

"We don't have the slightest idea why they come here," said Luis Gerra, economic counselor for the embassy of EI Salvador in Wahington. "We haven't had an earthquake or volcanic eruption lately."

Some State Department officials see economics as the reason. "EI Salvador is a very beleaguered country right now," said State Department official Eleanor Hicks. She attributed the steady exodus to a 20 percent inflation rate and a 40 percent rural unemployment rate in the sall country.

EI Salvador is the most densely populated in Central America and in the past year the country's military regime has been racked by political terorism.

While life in the Washington area may be better than what many aliens left behind, there are frequent problems for the aliens. "They suffer because it is not their culture, their values. They are always afraid of being caught," Alas said. "Many live like rabbits, 10 to a room and pay (low rents) so they can send money home."

Police and immigration officials confirm this. "A lot of these places are just flop (houses), wall-to-wall mattresses," said Crane. Many Salvadoreans live in Adams-Morgan, Mount Pleasant and Rosslyn.

Despite the apparent poverty in which many aliens live, the influx shows no signs of abating. In recent months immigration officials have asked for help in locating drop sites and apprehending smugglers from local police departments.

Antismuggling efforts have recently become a top national priority under Immigration Commissioner Leonel J. Castillo. His new anti-smuggling task force claims to have infiltrated 92 major sumggling rings and obtained 250 felony indictments since February. Within the next year officials said they expect Washington to be the target of stepped-up antismuggling activity.

Hispanic leaders say they are alarmed by this prospect. They claim that illegal aliens don't take jobs away from American but do the low paying work Americans spurn.

Last August President Carter proposed temporarily granting residence to the millions of aliens who have entered the U.S. since 1970. Estimates of the number of illegal aliens in the U.S. range from 4 million to 12 million.

A few weeks after Carter's proposal, still awaiting the Senate Judiciary Committee's approval, Gomez went to the immigration office on Vermont Avenue.

"He came strolling in here," Crane recalled, and said he's heard about the president's amnesty plan and wanted his green (work permit) card and wanted to work. We told him the sad, but true story about the situation (that the president's proposal was not in effect) Gomez was deported on Aug. 27 but was undaunted by the experience. "He turned around and was back in the U.S. by Sept. 1," Crane said.