Representatives of 25 community groups last week asked the D.C. City Council for swift passage of a bill that would make it extremely difficult for property owners to tear down or alter landmark buildings or to build incompatible structures in the city's historic districts.

"We desperately need this bill to be passed," said Ann Sellin of the Dupont Circle Citizens Association during the six-hour public hearing. Sellin added that there was an "alarming increase" in demolition activity in her neighborhood.

David M. Burns, another Dupont Circle resident, said that under present laws "many buildings are condemned to death - death will occur in 180 days."

Burns referred to the city's current law, under which the city only can delay for 180 days any proposed demolition or alteration to its 330 landmarks or to buildings in historic districts. The city now has no veto power over new construction in these districts. The only exception is in Georgetown, where, on the recommendation of the Commission of Fine Arts, a federal body, the city can deny building or demolition permits.

Under the proposed law, however, the city could refuse to issue deomlition or building permits where landmarks are involved unless, after hearings, the mayor determines either that the issuance of such permits is in the permits would result in "undue economic hardship."

Council member Nadine Winter, chairman of the council's Housing Committee which held the hearings, said she hopes new legislation will be passed by the council in October. Winter said she would like to have some sort of interim legislation to protect buildings that might be torn down before the new law takes effect.

Many of the witnesses at the hearing represented various preservation and civic groups around the city, including members of Don't Tear It Down, a group that drafted the bill during the past year in consultation with city civic organizations.

Some witnesses suggested amendments to the draft bill, such as expanding the act to include historic sites as well as buildings and refining procedures for notifying the Advisory Neighborhood Commissions, but most expressed the view that problems could be ironed out.

"Let's not have technicalities and conflicting egos delay the passage of this bill," urged Mary W. Jayne of the Stanton Park Neighborhood Association. Jayne told of two 19th Century houses in her neighborhood that were recently torn down after a 180-day delay under the current law.

Some witnesses, however, expressed strong reservations about the bill, Charles Atherton of the Commission of Fine Arts said that the bill's "restrictive design review process (for new construction in historic districts) might inhibit much needed development."

A representative of the Metropolitan Washington Board of Trade said that the burden of proof that a project was or was not in the public interest should be on the city, rather than on the property owner.

"This bill would freeze all progress in the city," said Theodore Mariani, reading an official statement from the local chapter of the American Institute of Architects. "The city is not a museum . . . historic Rome as we know it is about the seventh edition of that city."

Mariani, predicting "developers and entrepreneurs will go back to the Beltway" if the bill is passed, called for a broad-based task force to revise the draft bill.

"Don't Tear It Down had a very privy role in it, and hardly anyone else was consulted," said Mariani.

Winter said she would set up an ad hoc group of citizens to refine the legislation so that a bill would be ready for final consideration when the council reconvenes in September.

After members of Don't Tear It Down drafted the bill, it was reviewed and revised by city and federal agencies concerned. The mayor announced June 14 that he would soon send the legislation to the council. When the mayor failed to introduce the bill, citizens groups took it to council member John Wilson, who introduced it on June 28. Winter is a co-sponsor of the legislation.

Among the witnesses who generally supported the bill during the hearing were representatives of the Citizens Association of Georgetown, the North Dupont Community Association, the Logan Circle Community Association, the National Trust for Historic Preservation, the Friendship Citizens Association, Don't Tear It Down, the Society of Architectural Historians, the Capitol Hill Restoration Society. Neighborhood Housing Services, the Washington Junior League, the Patrons of the Adams House, the Mt. Pleasant Neighbors Association, the Committee of 100 on the Federal City, the LeDroit Park Citizens Association and several Advisory Neighborhood Commissions.