The owner of any property serviced by a building sewer carrying industrial waste shall, at the request of the director, install a suitable sampling station or stations upon each and every building sewer or combine the building sewers into one common building sewer upon which one sampling station shall be placed.  The sampling station or stations shall be furnished with such necessary meters and other appurtenances in the building sewer or sewers to facilitate observation, sampling and measurement of the wastes.  Such sampling station or stations shall be accessible and safely located, and shall be constructed in accordance with plans approved by the director.  The sampling station or stations shall be installed and maintained by the owner at the owner's expense and shall be maintained so as to be safe, accessible and in good working order at all times.  Said stations shall be secure with access limited to City and other authorized industrial personnel only.  (Ord. 90/T-9020)