Public domestic wells shall have an annular seal. On a public domestic well the space between the wall of the bore and the well casing or the conductor casing, if the conductor casing is left in place, shall be grouted to a depth of not less than fifty (50) feet from the ground surface except as follows:
A. In the event the space between the wall of the bore and the conductor casing cannot be grouted to a depth of fifty (50) feet, the space shall be grouted to the greatest depth possible and the space between the well casing and the conductor casing shall be grouted to a depth of not less than fifty (50) feet from the ground surface in such a manner that the grout will be forced out into the space between the wall of the bore and the conductor casing at the fifty (50) foot level. The grout shall form an effective seal which will preclude the vertical movement of water along the outside of the conductor casing between those aquifer lying above and below the fifty (50) foot level from the ground surface. In such cases, a gravel fill pipe may be installed through the annular seal on gravel packed walls.
B. Public domestic wells extending into hard rock shall be grouted no less than one foot into the first hard rock encountered.
C. Public domestic wells less than sixty-five (65) feet deep shall conform to requirements set by the building official at the time the permit is issued. (Prior code § 7799)