Putting new, federally mandated air pollution controls on the waste-to-energy incinerator in South Baltimore could cost the city $4.5 million to $9 million a year, says the city's top waste official.

George Balog, the public works director, said that when the U.S. Environmental Protection Agency adopts new pollution standards for municipal waste incinerators, the city would have to help pay for installing and operating new emissions control equipment at the Baltimore Refuse Energy Systems Co. facility on Russell Street.

Wheelabrator Environmental Services, which operates BRESCO, and the Northeast Maryland Waste Disposal Authority estimate that thecity's share of the cost of new acid gas scrubbers on the facility would be $2 million to $4 million a year, Balog said.

The city now pays $34 a ton for the 270,000 tons of garbage it trucks to BRESCO each year, Balog said. But that tipping fee is likely to increase to pay for the new emissions controls, and the cost to the city of disposing of household waste.

Mayor Kurt L. Schmoke met last week with top EPA officials to ask them to be "flexible" in tightening pollution limits on existing municipal incinerators like BRESCO, since the city can ill afford huge new expenditures.

Schmoke said he supported cleaning up incinerator emissions, but he questioned the environmental benefits of setting such stringent limits.

He urged EPA to reconsider requiring incinerators like BRESCO to replace existing pollution-control equipment with more efficient equipment in order to remove particulates from smokestack emissions.