Yes, but each and every metal in solution must be BELOW the Discharge Ordinance Limit or specific permit limit, whichever is LOWER. AND, the solution must meet the restrictions for pH. If the solution is not a candidate for sewer disposal it must be disposed of through the UA, Hazardous Waste Program.
No. This would be considered "single pass cooling" and is prohibited by the Ordinance. In addition, this practice is wasteful as conditioned water would be lost to the sewer and this is also considered hydraulic loading of the Publicly Owned Treatment Works.
Small quantities of ethanol may go down the drain with a quantity of water at least ten (10) times the volume of the ethanol. Sewer disposal of methanol and isopropyl alcohol is prohibited.