The D.C. City Council, rejecting arguments that black-owned businesses would be hurt economically, yesterday gave preliminary approval to a bill to include Asian Americans and Hispanic Americans of European descent in the city's $115 million-a-year minority contracting program.

The measure, approved by voice vote, reverses the council's 1980 decision to eliminate those groups from the program, which sets aside 25 percent of the value of city contracts for minority-owned firms. The city's growing Asian American and Hispanic communities had lobbied intensively for the reversal.

The set-aside law currently applies to blacks, native Americans and Hispanics from Central America, South America and the Caribbean.

The bill, which must be approved on a final reading, was passed with little of the acrimonious debate that characterized a public hearing on the issue last May. At that earlier hearing, several owners of black businesses complained that the contracting program was poorly run and ineffectual.

Council member Wilhelmina J. Rolark (D-Ward 8), opposing the measure, argued yesterday that the bill "in the face of stark economic and social realities" would make it far more difficult for black businesses to survive.

She said the original intent of the law was to aid blacks, historically the victims of discrimination. Much of the debate on the issue has centered on whether Asians and European Hispanics have suffered such "historic discrimination."

Rolark and Council members Hilda Mason (Statehood-At Large) and Polly Shackleton (D-Ward 3) abstained from voting on the bill. H.R. Crawford (D-Ward 7) was absent when the vote was taken.

"There are those now who are being denied the opportunity to compete," said council member Charlene Drew Jarvis (D-Ward 4) in support of the expanded definition.

Representatives of the Hispanic and Asian business communities yesterday praised the bill.

"It means finally justice was done," said Eduardo Perdomo, a past president of the Hispanic American Contractors Association and owner of a local construction company. "Hispanic businessmen will have a little boost in the city."

Perdomo said he expected fewer than two-dozen Hispanic firms would be affected initially by the law, but said the measure would encourage the formation of new companies.

Ronald Hsu, owner of a Prince George's County construction firm, said local Asian businesses "lobbied hard" for the change. He said there would be no large immediate impact on the Asian American community here, but added, "I think in the future the important part is the definition."

Hsu said the city was wrong to eliminate the two groups in 1980 after some complaints that wealthy Hispanics of European descent were benefiting from the law. "It's not right for one minority to discriminate against another," Hsu said.

Former council member Willie J. Hardy, who led the fight to exclude the two groups in 1980 and testified against the amendments in May, said yesterday that the changes "would have a devastating effect on small black businesses trying to economically compete."

Hardy said the council took the two groups out of the bill in 1980 because it decided they had not experienced the "historical discrimination" suffered by other minority groups in the United States.

Several council members have said the reversal was due to the status of the two groups as growing, politically active constituencies.

The groups are legally considered minorities by the federal government.

William Jameson, executive director of the city's Minority Business Opportunity Commission, which runs the minority program, said yesterday that he supported the change but said it is unclear what effect the the legislation will have on the program.

He said there are about 400 qualified firms registered to participate.

In other action, the council gave final approval to permanent legislation designed to make it easier for authorities to detain repeat offenders before their trials. The legislation is identical to emergency measures already passed by the council and currently in effect.