13.16.490   Access and air vent pipe.
   All wells shall be provided with a pipe or other effective means by which disinfectants can be introduced into the well or the depth of the well may be measured. The pipe, if provided, shall be extended to a height of not less than three inches above the concrete base and shall be kept sealed and shall be provided with a threaded cap. On public domestic wells, the pipe shall also serve as an air relief vent, terminate downward, be covered with sixteen (16) per inch or finer wire mesh screen and be protected against the possibility of contamination by material entering the pipe. (Prior code § 7808)