The company stopped the burning and decided to replace the incinerator with an autoclave, which sterilizes medical waste under superheated steam, turning it into trash that can be dumped in ordinary landfills.

The contractor has hired a subcontractor to transport sludge to ordinary landfills in other states.

It also removes mercury switches, as well as electronic capacitors containing PCB's, so that the residue left after the metals are recycled can be buried in an ordinary landfill.

Under the law, ash deemed to be hazardous must be disposed of in licensed installations that protect ground water better than ordinary landfills do.

For equivalent volumes of waste, hazardous-dump operators charge municipalities as much as 1,000 percent more than do ordinary landfills.

And that would allow continued disposal of the ash in ordinary landfills.

It is not transporting sludge to "ordinary landfills" as Ms. Maloney alleges.

If the ash can be buried at low cost as ordinary landfill, the energy-producing incinerators would make economic sense for many cities.

The ash is buried in an ordinary landfill in Michigan for about $23 a ton; it would cost about $210 a ton to store the ash as hazardous waste.

About 50,000 tons of material that is not radioactive will go to an ordinary industrial landfill in Niagara County, N.Y.