University of the District of Columbia students have intensified the battle to have a $56.7 million campus built downtown.

Angry students marched through downtown Washington this week and last week, held a "teach-in," wrote a letter to Vice President Walter Mondale, and have called on Sen. Patrick J. Leahy (D-Vt.), chairman of the Senate subcommittee, to release construction funds.

At issue, according to students, is whether a single campus should be built in a predominately white community on upper Connecticut Avenue, which students say is difficult to attend because of its distance from many black Washington communities.

After months of delays and bitter bureaucratic battles between UDC and the Senate subcommittee overseeing the District budget only 10 days remain to decide the issue.

If the Senate subcommittee on D.C. appropriations does not release to the city any of the money set aside to build the Mount Vernon Square campus by Sept. 30, UDC faces the possibility of having to request a whole new construction budget for the campus. Getting approval for the campus again could be difficult if not impossible, according to school officials.

In addition to attending classes at the Van Ness campus, students are also taught in 14 leased office buildings scattered throughout downtown Washington. Students complain that two of these buildings have been condemned and that leased office space does not provide a good educational environment.

The delays, according to university officials, are costing UDC nearly $400,000 a month. The $56.7 million that would originally have paid for 712,000 square feet of space now will pay for 38.5 percent less, or 437,820 square feet.

Part of the reason for the delay in construction of the downtown campus is due to disagreement over a proposal by Leahy. He has suggested that instead of building the downtown campus, UDC should use land adjacent to the Van Ness campus for a single campus site. This proposal has been rejected by students, administrators and residents in the Van Ness area.

And recently, a General Services Administration study of the use of the 11 acres adjacent to the Van Ness campus reported that the land was better suited for chancellories, which are already under construction by the state department.

Abdul-Raheem Abdullah, 27, UDC student government president, said "If we put it all here (at the Van Ness campus), they could then say it was centrally located, but you could also say it's all in one community -- it's all in the white community."

Joseph McAldred (Big Mac) Gorham, the 27-year-old student program director of WUDC radio, the on-campus station, said some black students have a sense of educational doom.

"Some people feel the Van Ness campus would be for whites and foreign students and Mount Vernon would be for blacks."

He added: "If the whole university is at Connecticut and Van Ness, they will be pushed out of the higher education system. Nobody wants to get pushed out."

UDC student Brenda Willis, interviewed on the campus, said she believed there are those who want UDC to remain in the predominately white section of town because whites are now migrating back to the city.

University statistics indicate that between 1977 and 1978, non-blacks increased from 9.9 percent to 13.7 percent of the school's enrollment.

The student government association president added, "I would like to believe the problems we are facing are a matter of getting all of the particulars together and not a racial issue."

Other students, however, said they believed the delays were both racial and economic. They said they believe the Mount Vernon Square campus, located at 9th and Mount Vernon streets Northwest on two square blocks is tempting to those who want to use the land for commercial use.

Fueling those suspicions was acting UDC alumni president, Joseph Webb, 29, assistant director of the adult education center at Franklin school and a 1971 graduate of D.C. Teacher's College.

He told a crowd of student demonstrators recently: "I want to pass on this rumor. I have been told that there are secret negotiations under way between the District government and private parties to build a hotel and shopping center on the Mount Vernon campus site. If our time runs out we should be sure to look at who is proposing legislation for a hotel on the Mount Vernon site."

Webb, who said the UDC issue is a hometown issue, explained that he and others have been fighting for the downtown campus for more than 10 years. He said nearly 200 people gave up their homes at the Mt. Vernon site because they were told that a campus for District students was to be built.

Diane Lewis, a special assistant to the mayor, said the mayor supports a downtown Mount Vernon campus and is working to have the funding released before Sept. 30.

Another factor adding support to the claim that an additional campus is needed is the fact that UDC's enrollment has increased 10.6 percent, the first time there has been an increase since 1975, according to UDC president Lisle C. Carter Jr., who made the announcement earlier this month.