Metro's infamous Green Line, first drawn in 1968, is still the hotly contested subject of public debate. After 14 years of waiting, citizens, local government leaders and Metro officials still gather in steamy auditoriums to argue about which way the subway will go.

Every additional day of dispute increases the cost of the project and the chances that the long-promised Green Line will never cross the Anacostia River and drill its way into Southeast Washington and southern Prince George's, say Metro officials.

While District leaders, with the apparent backing of most Southeast Washington residents, firmly support a southerly line ending at Rosecroft Raceway, it remains unclear which route, if any, will please their Prince George's neighbors. Some Prince George's residents said at a public hearing last week they are ready to sue Metro again, which would mean more construction delays.

The 1968 route map shows the Green Line ending on Auth Road near Branch Avenue. But with Anacostia and Prince George's officials asking for the Rosecroft line, and the Branch Avenue route appearing more costly and more technically difficult than earlier imagined, Metro's board of directors changed its mind in 1980 and opted for the Rosecroft route.

The County Council voted for the Branch Avenue route in 1978, but declared a few weeks later it was willing to support either route. A few weeks after that, the council voted again and decided it wanted the subway to run to Rosecroft.

There was no wavering by supporters of a Branch Avenue route, however. Several community organizations argued that Metro's board of directors did not give proper notice for public hearings on the route change, and an automobile dealer near the proposed Branch Avenue terminal sued to have the decision reversed.

In February 1981, a U.S. judge in Baltimore ruled that Metro must hold new hearings in Prince George's. The ruling was appealed and earlier this year a higher court decided that if Metro wants to abandon the Branch Avenue plan it must first stop Green Line construction, hold hearings in both the District and Prince George's and rethink its position.

Metro held these hearings last week, and the deep divisions that have delayed the Green Line surfaced once more. At the Birney Elementary School in Southeast Washington, the citizens heartily endorsed the Rosecroft route. But Prince George's residents who gathered the next day in Hillcrest Heights overwhelmingly supported the Branch Avenue line.

Many of the Prince George's citizens complained that they voted for an $88 million bond issue for Metro in 1968 on the assumption that the subway would come into their neighborhoods. They said they may sue Metro again if the transit authority opts for the Rosecroft line.

"Voters are upset that the votes of the people are being ignored," said Paul J. Melucas of the Auth Road Citizens' Council. "To me, that's unlawful and unconstitutional. If they want to change the route they should put it on a referendum and let the people vote."

City politicians and many Southeast Washington residents have watched with frustration as the rail system has stretched up Connecticut Avenue towards Montgomery County while Anacostia, one of the city's most heavily populated and poorest areas, remains unserved. They put much of the blame for delays on Prince George's.

"Despite hours of hearings, months of study and years of debate, the Metro in Anacostia is no more a reality now" than it ever was, District of Columbia City Council chairman Arrington Dixon complained at last week's hearings. "I am deeply worried and angered over the clear and present danger that the Anacostia community will never enjoy the benefits of the rapid rail system."

Staff members expect to hand a report, with recommendations, to the transit authority's board of directors in the fall. Once a decision is made, Metro is ready to start constructing a tunnel under the Anacostia River. Still, the Green Line is unlikely to reach southern Prince George's for another 10 years.

Like most Anacostia residents and representatives of organizations who spoke at last week's hearings, Dixon wants the subway line to tunnel under the Anacostia at the Washington Navy Yard, under Martin Luther King Jr. Avenue, and head south past St. Elizabeths hospital and through Congress Heights, to end at the Rosecroft Raceway near the Beltway in Prince George's.

Metro officials say the Rosecroft line would displace about 265 people and 10 businesses, and would carry about 15,500 people during peak morning hours and 65,370 people on the average day. It would cost about $694 million to build, and about $28.3 million to operate each year.

But a group of Prince George's citizens, spurred on by State Delegate Lorraine M. Sheehan from Suitland, County Council member Sue V. Mills from Oxon Hill, and an organization called Citizens for Branch Avenue Metro, argued at the hearings for a line that would cross the river near the 11th Street bridge, chisel its way under Good Hope and Naylor roads to join the Suitland Parkway at the District line. It would leave the Parkway at Silver Hill Road and head southeast to a terminal at Auth Road, near Branch Avenue just inside the Beltway.

Metro officials say this route would displace about 718 residents and 27 businesses, and would carry about 14,110 people during peak morning hours and 62,740 people a day. Construction would cost $734 million, roadway improvements would cost at least $12 million, and the line would cost $29.5 million to operate each year.

A less expensive line would follow the Rosecroft route into Anacostia, but would then veer east onto the Suitland Parkway to the District line, after which it would follow the original Branch Avenue route. This would displace 76 residents, fewer than any other proposed route, would cost slightly less than the Rosecroft line, require fewer road repairs, but would carry about 1,000 fewer passengers a day.

Another variation offered by Metro follows the Rosecroft line through Congress Heights to the District Line, but then veers east and follows Southern Avenue to the Suitland Parkway. It would satisfy supporters of the Rosecroft line in Anacostia, and the Branch Avenue supporters in Prince George's, but at an estimated $808 million it would be the most expensive line to build.

Bill Cairns, who owns a large Pontiac dealership just over a thousand feet from where the Branch Avenue terminus was planned, was so angry he sued Metro. "I bought this land six years ago, and when I bought this land, I was told that this line was going to be right behind. It was on the master zoning plans. . . . It wasn't the total reason I moved here, but it was a very big factor."

Steve Tupper, special assistant to the director at the U.S. Census Bureau in Suitland, argued that the Branch Avenue route would follow proven traffic patterns and serve high employment areas like Andrews Air Force Base and the Federal Center in Suitland. "Because the federal government owns land and has a tradition of being here, there would be tremendous incentive for building out here," he said.

County supporters of the Rosecroft line, however, say so many of the workers in Suitland live in the District or Virginia that Prince George's has little to gain.

District leaders object to the Branch Avenue route because it leaves out the Congress Heights stop. John A. Drayson, assistant director of mass transport for the city's Department of Transportation, said Congress Heights has one of the District's highest populations of people dependent on public transport. "We don't care where the terminal might be in Prince George's County, but we want the line to go to Congress Heights. It's vital." he said.

According to Metro calculations, the original Branch Avenue route would displace about 634 people who live in Anacostia, 25 businesses and four institutions, while the Rosecroft route would displace about 192 people, 10 businesses and one institution.

Not every Anacostia resident favors the Rosecroft route, however. Attorney David H. Cox represents a group of residents in the Good Hope Road and Naylor Road area, where the Branch Avenue route would run. He wants Metro to choose a compromise line that would use the same station on Martin Luther King Jr. Avenue called for on the Rosecroft route, but would then follow the Suitland Parkway to Naylor Road where it would join the original Branch Avenue line.

"My clients appreciate the Congress Heights problem," Cox said. "But in these circumstances it would seem to me more fair to the people who were told for 10 years they would get a Metro station , to give them at least one station near to where they live and work."

And there remains strong oppostion to a Branch Avenue route in Prince George's. The 30-year-old Rosecroft Raceway, which has seen average daily attendance during its 85-day summer racing season slip from the 6,000 it enjoyed in its early days to its current 4,200, is eager to have a Metro stop on its doorstep.

"It would definitely help attendance and I think it would help the community as well," said raceway director Thomas Aldrich. He noted that the state would also benefit, by collecting more in betting taxes.

Aldrich said the Branch Avenue route would also help the track, though not as much. "If it goes to the Branch Avenue route, what we'd probably do is send shuttle buses out to the Branch Avenue Route." Rosecroft is about 2 1/2 miles from the Branch Avenue terminus.

Many Branch Avenue supporters charge that Peter F. O'Malley, a lawyer for Rosecroft Raceway and the adjacent landowners, influenced the County Council's vote for the Rosecroft route. O'Malley, a powerful county Democrat, was a political strategist for the Democratic council and former county executive Winfield Kelley, who were then running for reelection. But while making his support of the Rosecroft route clear, O'Malley has denied using his political influence to get the council's support.

Ella E. Ennis, a County Council candidate from Fort Washington, which is nearer the Rosecroft route, told Metro officials at the hearings that such accusations of political manipulation were nonsense. She argued that the Rosecroft line would be less expensive, cost less to operate, and carry more passengers than the Branch Avenue line, and would serve an area of rapid development. "If you listen to the Branch Avenue people, you'd think we have nothing but farms down here," she complained.