A Superior Court jury convicted Los Angeles Doctor's Hospital on a felony charge of having illegally disposed of hazardous waste by dumping 200 gallons of diesel fuel into a street and storm drain across from an elementary school. Judge Richard Kalustian set a sentencing hearing for Sept. 24. The hospital faces a fine of up to $100,000. The charge stemmed from the disposal of diesel fuel waste from hospital tanks by Robert Smallwood and Walter Holton of Bob's Steam Cleaning and Truck Wash on June 3 and 4, 1985. Smallwood and Holton, neither of whom was licensed to handle hazardous wastes, worked under the supervision of A. Vaji Nasoordeem, the hospital's chief mechanical engineer.