All pumps shall be constructed and installed so as to provide protection against contamination and pollution of the underground aquifers. Pumps and pump motors installed directly over the casing of any well shall be provided with a sanitary seal between the pump base and the casing. Installations with submersible pumps or pumps offset from the casing shall also have a sanitary well seal. No pipe or conduit shall enter the casing from the side except access or air vent pipes as required by the ordinance codified in this chapter except those fittings which are NSF approved. (Prior code § 23-44)