NAC445A.6689. Water wells: Casing.

     1. Except as otherwise provided in subsection 2, a water well must be cased to the bottom of the drill hole and constructed in such a manner as to prevent any pollution or contamination of the groundwater.

     2. If no additional water is developed in the bottom portion of a water well, neat cement, cement grout or concrete grout may be placed by tremie pipe from the total depth to the bottom of the casing.

     3. The casing must:

     (a) Be composed of:

          (1) A quality of steel that complies with American Water Works Association Standard A100; or

          (2) Where authorized by the Division of Water Resources of the State Department of Conservation and Natural Resources, a quality of PVC that complies with American Water Works Association Standard A100.

     (b) Be free of pits and breaks.

     (c) Conform to the following minimum specifications, allowing for mill tolerance:

          (1) If the conductor casing is 50 feet or less in depth, the wall of the casing must be at least 0.141 or 9/64 of an inch thick.

          (2) Except as otherwise provided in subparagraph (3), if the depth of the conductor casing exceeds 50 feet, and for all production or intermediate casing, the wall of the casing must comply with the following requirements:

               (I) If the nominal size of the casing is smaller than 10 inches, the wall must be at least 0.188 or 3/16 of an inch thick.

               (II) If the nominal size of the casing is 10, 12, 14 or 16 inches, the wall must be at least 0.250 or 1/4 of an inch thick.

               (III) If the nominal size of the casing is 18 or 20 inches, the wall must be at least 0.312 or 5/16 of an inch thick.

               (IV) If the nominal size of the casing is larger than 20 inches, the wall must be at least 0.375 or 3/8 of an inch thick.

          (3) If the depth of the well exceeds 300 feet, the thickness of the wall of the casing must be increased in accordance with American Water Works Association Standard A100.

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