Pasco County commissioners expect a crowd at a public hearing at 6:30 tonight on a controversial medical waste incinerator proposed near Gowers Corner. The question will not be whether an incinerator should be allowed, but how large an incinerator is permissible on 10 acres near the Kent Grove subdivision. Bon-Bar Leasing Inc. wants to burn up to 4,500 pounds of waste per hour. It argues that a county zoning board did not limit the size of the incinerator when it granted the company special approval for an incinerator in 1989. County officials say the zoning approval allows an operation burning only 800 pounds of waste per hour. The hearing will be at the Pasco County Government Center, 7530 Little Road.