The trouble began for Eddy Marvin Thompson with the Arab oil embargo. Gas was short, money was shorter and his Texaco station on Georgia Avenue NW was running on empty. Thompson's dream of owning a successful business began to fade, and the checks he wrote started bouncing.

Seven years later, that dream finally collapsed--after Eddy Thompson had written an estimated $70 million worth of checks and handled about $200,000 cash a day in a bizarre and ultimately fruitless attempt to keep Thompson's Texaco alive.

Four days a week, every week, since 1976, Thompson had been carrying ever-increasing amounts of cash--finally totaling almost $1 million a week--from a District branch of American Security Bank to a Maryland branch of Citizens Bank & Trust.

With bulging money pouches and, later, shopping bags full of cash in his car, Thompson shuttled between the two banks, trying desperately to cover his mounting losses by juggling his accounts in a massive and illegal check-kiting scheme. When it all ended, he had pumped $204,800 in bank funds into his gas station.

Most of the checks Thompson cashed were approved by two American Security officials, who were subsequently fired and now face federal criminal charges for not reporting the cash transactions.

Thompson had become trapped on a nonstop financial merry-go-round of his own making that lasted until February 1982, when federal authorities uncovered the transactions during a routine audit. He was convicted last week in U.S. District Court in Baltimore on 20 felony counts of interstate transportation of stolen money and awaits sentencing next month. He faces up to 10 years in prison and a $10,000 fine for each count.

Thompson, 39, is the father of five, with no previous criminal record, who ran his gas station at 4000 Georgia Ave. NW for 16 years. "Never once did it occur to me that what I am doing was illegal. I knew it was bad business . . . but I didn't know how banks function and operate," said Thompson, who has a 10th-grade education. "Never once in this life did I do anything illegal, and I've always stayed away from people who did," he said.

"I could have disappeared to almost anywhere with a million dollars. Gone to Bolivia . . . . But I never did. Never took any money," Thompson said during a lengthy interview at the modest split-level home in suburban Baltimore that he and his wife Deborah, a schoolteacher, bought for $34,000 in 1972.

Federal authorities said they found no evidence that Thompson pocketed any substantial amount of money or altered his life style as a result of his seven-year juggling act. The money, they said, was apparently all used to keep his Texaco station afloat.

Thompson testified he didn't think the check cashing was illegal because officials at the American Security bank at 3500 Georgia Ave. NW had allowed it. He said he thought they were essentially extending him credit.

But Assistant U.S. Attorney Steven A. Allen presented evidence that Thompson was told at least four years ago that the scheme was illegal.

Luther R. Pinkard, the former manager of the American Security branch, testified at Thompson's trial that he warned Thompson as early as 1979 that the scheme could cost Pinkard his job and land them both in prison. Pinkard said he only became aware of Thompson's check-writing scam after Thompson already was cashing about $10,000 a day in bad checks.

Pinkard and his assistant, Dorothy Bierer, both testified that after discovering the scheme they went along with it for fear they would be fired if it was detected. Neither received any of the money, prosecutors said. Pinkard, Bierer and a spokesman for American Security all declined to be interviewed.

Thompson is a big, beefy man, street-smart and well-spoken. When he tried to recount in the interview what happened to him over the past seven years, he would close his eyes and hang his head in exhaustion. When he tried to describe the arcane scheme, he confessed, "it confuses me, too."

Thompson is an unlikely candidate for a multimillion-dollar check scam. He grew up poor. His mother worked briefly in a laundry but quit for health reasons and raised her four children on welfare. Thompson never knew his father.

As a youngster he lived at Massachusetts Avenue and Second Street NW, but spent much of his time hanging around the Third Street Amoco station. He worked there after school, standing on a Coca-Cola crate so he could reach up and clean windshields, until he got a little taller and the cars got a little smaller.

In a neighborhood where poverty and joblessness were common, Thompson said, the man who owned the Amoco station became a model for him. "I guess it was then I started having the dream of my own neighborhood service station," he said.

Thompson dropped out of Dunbar High School in the 11th grade when he got a girl pregnant, he said. He married her and took a job as a salesman for a vending machine firm, but the job and the marriage both ended shortly afterwards. In 1966, Thompson, then 23, landed a $7,500 minority enterprise loan through the Small Business Administration and opened his own service station.

"I was always a proud individual. I was proud when I went into business," he said. Thompson said his mother raised him, his brother and two sisters with a respect for hard work and the law. "And she has never had to go to the jailhouse for any of us."

Thompson's Texaco fared well in its early years, pumping up to 45,000 gallons a month and providing Thompson about $15,000 in salary and up to $10,000 profit, he said.

But the oil embargo cut Thompson's gas allocation in half and he never recovered from the loss of customers. Meanwhile, as his rent and utility costs increased, the cash flow decreased.

While many stations were shutting down in the wake of the gas shortage, Thompson was determined his would not. "I should have gone out of business," he said. " . . . I didn't want to give up."

The gas station generated several hundred dollars in cash daily, but not enough for Thompson to pay Texaco for gas and meet his other expenses. In the early 1970s, he began getting letters and calls from Pinkard about the chronic overdrafts of his business checking account at American Security.

Gradually, according to Thompson, Pinkard was drawn into the deteriorating situation at Thompson's Texaco. He recalled one instance when Pinkard told him he didn't have the money in his account to cover a check he had written for about $400. Thompson pleaded with him, saying he would have the cash by the end of the day or first thing the next day. Pinkard agreed to pay the check, and Thompson delivered the cash the next day, Thompson said.

Thompson continued to write business checks he couldn't cover. Pinkard called him frequently to warn him his account was overdrawn. Thompson would promise to deliver the cash. But, by 1976, he couldn't always come up with enough. It was then that Thompson began using checks from his personal checking account at Citizens Bank & Trust.

According to the FBI and prosecutor Allen, the scheme worked this way: On "Day 1," if Thompson knew that his American Security business account was overdrawn by $2,000, he wrote a $2,000 personal check from CB&T for deposit at American to cover the business checks that were about to bounce.

But Thompson did not have enough on deposit at CB&T to cover the personal check he'd just written.

So, on "Day 2," he would write a second CB&T check payable to himself for $2,000, but this time he would cash it at American Security. Then he would drive to Silver Spring and deposit the cash at CB&T to cover the Day 1 check before that check was processed through the Federal Reserve Board clearinghouse in Baltimore.

So the treadmill began rolling: To prevent the Day 2 check from bouncing, Thompson would have to write and cash a check on Day 3. The cycle continued inexorably, while Thompson hoped he could somehow generate enough cash to pay his overdrafts. But his debts only mounted.

Thompson "had started a circle and had to keep it going or the whole thing would fall down," prosecutor Allen told the jury.

"I couldn't afford to be sick. I couldn't go out of town. I couldn't be away from the station for one day," recalled Thompson, who was hospitalized by a heart attack in 1976 just before the check scam started.

Thompson developed a daily banking ritual. He drove an hour from his home to the station, opened the floor safe, totaled his overnight cash receipts and drove to American Security.

Pinkard or Bierer would initial his CB&T checks, approving them for cash payment. Then Thompson would be off to Silver Spring--initially using a money pouch, then shopping bags and finally a five-inch-thick attache case. The sums became so large that the Georgia Avenue branch of American Security occasionally ran out of cash and gave Thompson cashier's checks instead.

Thompson was in constant fear of a holdup, he said, so he would vary his route to the bank and occasionally use a different car. His daily routine included hours of waiting for harried bank tellers to count his massive deposits. Only once or twice, he said, did anyone ask him about the cash. He just said it was cash receipts from a gas station.

As Thompson saw himself sinking, he tried various ways to build business and earn enough cash to get off the merry-go-round. He stayed open 24 hours a day. He hired a full-time manager (because Thompson himself was spending three to five hours daily on his banking). He borrowed $15,000 from American Security and took out a second trust on his home to raise cash. But all of his efforts only cost him more money and did little to generate business.

Gradually, the amounts of the daily checks grew. By 1980, they had skyrocketed to $27,000 a day as Thompson tried desperately to expand his business. In the end, the amount had mushroomed to $204,800 a day. Last year, American Security successfully sued Thompson to recover that amount but has yet to collect it.

Law enforcement officials believe that $204,800 is roughly the sum that Thompson's Texaco lost during the seven years. But he was able to cover the losses with the ever-increasing amounts of his checks.

Thompson said he often worked seven days a week and was constantly preoccupied trying to figure a way out of his predicament. "I knew it was lost. But the merry-go-round was going too fast to get off," he said. He tried to sell the business in 1980 but found no takers.

Finally, it all collapsed in February 1982, when a federal currency task force, including the FBI and IRS, came across Thompson's unusually large cash deposits at CB&T. Federal authorities also found Pinkard and Bierer were failing to file Currency Transaction Reports (CTR) that the Federal Reserve requires for any cash transaction more than $10,000.

Pinkard, who suffered a heart attack in 1979, and Bierer, who worked for American Security for more than 20 years, were both fired and agreed to plead guilty to a misdemeanor charge of failing to file CTRs. They also agreed to testify against Thompson.

Thompson's lawyer, Clement T. Cooper, said he plans to appeal the conviction and the $204,800 judgment against his client.

Thompson described his life as a bad dream. "A million times I have thought about how I want to go back" in time and start over, he said.

"I was willing to do whatever was necessary, within legality, to stay in business," he said. "I always believed whatever obstacles came up , I could overcome it. To quit and walk away would be defeat . . . . I had grown up as an underdog, and I didn't want to admit that that business beat me."