36.21.808 SITE PROTECTION AND SECURITY
(1) The top of the well shall be fitted with a tight fitting slip cap, threaded plug or cap, or locking cap. Monitoring wells within the radius of influence of a well used as a domestic supply well and hydraulically connected to the aquifer from which the well is drawing water shall have a locking cap or be surrounded by a fenced controlled enclosure.
(2) The following are suggested methods for site protection:
(a) If the well is cased with metal and completed above the ground surface, a lockable watertight cap may be welded to the top of the casing.
(b) If the well is not cased with metal and completed above the ground surface, a metal protective casing may be installed around the well. The protective casing may extend at least six inches above the top of the well casing and at least two feet into the ground. A lockable cap may be welded to the top of the protective casing.
(c) If the well is completed below ground surface, a lockable "water-meter cover," or equivalent, may be installed around the well. The cover must be designed to withstand the maximum expected loadings. A watertight seal on the casing itself shall be installed to prevent the inflow of surface water. Drains may be provided, when feasible, to keep water out of the well and below the well cap.
(3) The well(s) completed above ground may be protected from damage by one of the following suggested methods:
(a) Three metal posts at least three inches in diameter may be installed in a triangular array around the casing. Each post may extend at least three feet above and below the ground surface.
(b) A reinforced concrete pad may be installed to prevent freeze/thaw cracking of the surface seal. When a concrete pad is used, the annular seal shall be contiguous to the concrete pad.
(c) Other methods agreed upon by the well owner and the monitoring well constructor may be used.
(4) The final surface should be sloped away from the monitoring well. If slabs or pavements prevent this, the surface should be sealed with at least four inches of Portland cement or asphaltic concrete. A surface condition which allows surface runoff to run down the side of the casing or borehole is unacceptable and shall be repaired.
History: 37-43-202, MCA; IMP, 37-43-202, MCA; NEW, 1988 MAR p. 2503, Eff. 11/24/88.