Old building sewers may be used in connection with new buildings only when they are found on examination and testing by the Director of Public Works to meet all requirements of this chapter. If an old building sewer is abandoned by the property owner, the city requires that the old sewer be disconnected and capped at the point of attachment with the main to the sanitary sewer system. The cap should be approved by the city and must be inspected by the city prior to backfilling.