NAC445A.66915. Water wells: Slabs and pedestals; construction with lineshaft turbine pump or submersible pump.

     1. A water well with an above-ground discharge must be protected by a concrete slab and, if the well is equipped with a lineshaft turbine pump, with a concrete pedestal, both of which are constructed of continuously poured concrete. The pedestal must be of a sufficient diameter to extend at least 3 inches beyond the outer periphery of the sanitary seal. The slab must:

     (a) Be placed above the finished grade;

     (b) Have a minimum thickness of 6 inches;

     (c) Slope away from the pedestal at a minimum slope of 2 percent;

     (d) Extend a minimum of 4 feet from the casing of the well in all directions; and

     (e) Be free from cracks and other defects likely to detract from its capability to remain watertight.

Ê The casing of the well must extend to a height of at least 12 inches above the slab and at least 18 inches above the level of the final ground surface or 100-year floodplain, whichever is greater.

     2. If a water well is equipped with a lineshaft turbine pump:

     (a) The top of the casing must be sealed into the base of the pump or the casing must be inserted into a recess extending at least 1 inch into the base of the pump.

     (b) The foundation and base of the pump must be designed in such a manner as to prevent water from coming into contact with joints between the base of the pump and the casing, and from entering the well.

     3. Any submersible pumps installed in a water well must be constructed in accordance with American Water Works Association Standard E101.

     (Added to NAC by Bd. of Health, eff. 2-20-97)