Wyo. Code R. 037-0009-5
Effective Date: 03/05/1974 to 04/06/2010
Rule Type: Superceded Rules & Regulations
Reference Number: 037.0009.5.03051974
a. When artesian water is encountered in a well, unperforated casing shall extend into the confining layer overlying the artesian zone. This casing shall be adequately sealed with cement grout into the confining zone so as to prevent both surface and subsurface leakage from the artesian zone. (See Figure 3A on page 17.) The method of construction shall be such that during the placing of the grout and the time required for it to set, no water shall flow through or around the annular space outside the casing, and no water pressure sufficient to disturb the grout prior to final set shall occur. After the grout has set completely, drilling operations may be continued into the artesian zone. If leakage occurs around the well casing or adjacent to the well, the well shall be recompleted with any seals, packers, or casing, necessary to eliminate the leakage completely.
b. If water flows at the surface, the well shall be equipped with valved pipe connections, watertight pump connections, or receiving reservoirs set at an altitude so that flow can be stopped completely. There shall be no direct connection between any discharge pipe and a sewer or other source of pollution,
Section 2. Construction of Gravel Packed Wells. The diameter of an oversized drill hole designed for the placement of an artificial gravel pack, shall be such as to allow a thickness of gravel or sand outside the casing sufficient to block the movement of natural earth materials into the well. The size of the openings in the casing or screen shall be based on the size of the gravel or sand used in the gravel pack. After completion, the well shall be overpumped, surged, or otherwise developed to insure free entry of water without sediment. A gravel packed well shall be sealed in one of two ways to prevent pollution to the ground water supply:
a. If a permanent surface casing is not installed, the annular opening between the casing and the drill hole shall be sealed in the top IO feet with concrete or cement grout. Access pipes used to inject gravel may be installed in the annular space prior to sealing, provided that the seal around the injection pipes remains watertight, and that such pipes are covered with a watertight cap or plug. (See Figure 4A on page 1B.)
b. If a permanent surface casing is installed, it shall extend to a depth of at least IO feet. The annular opening between this outer casing and the inner casing shall be covered with a metal or cement seal. (See Figure 4B on page 1.B.) Access pipes used to inject gravel may be installed in this seal, provided that the seal around the injection pipes remains watertight, and that such pipes are covered with a watertight cap or plug. A watertight concrete pump base tied to the surface casing, may serve in place of the above seal between casings.
a. Any time during the construction of a well that mineralized water or water known to be polluted is encountered, the aquifer or aquifers containing such inferior quality water shall be adequately cased or sealed off so that such water shall not enter the well, nor will it move up or down the annular space outside the well casing. (See Figure 3B on page 17.) If necessary, special seals or packers shall be installed to Prevent movement of inferior quality water,
b. In gravel packed wells, aquifers containing Inferior quality water shall be sealed by pressure grouting, or with special packers or seals, to prevent such water from moving vertically in gravel packed portions of the well,
a. Existing oil and gas wells, seismic test holes, or mineralexplorationholes, may be converted for use as water wells, provided that the wells can be completed to conform to the minimum construction standards cited herein. A permit to appropriate ground water must be obtained from the State Engineer prior to use of the water, Also, before any oil or gas exploration hole or well is converted for use as a water well, a written request for conversion must be approved by the Wyoming Oil & Gas Conservation Commission as specified in Rule 312 of the Rules and Regulations of that Commission,
b. Information on the geologic conditions encountered in the well at the time of the original drilling, shall be used to determine what special construction standards shall be met in order to eliminate all movement of pollutants into the well or along the annular space surrounding the casing. If no original geologic information is available, an electric or other geophysical log may be required to supplement known information,
Section 5. Modification of Existing Water Wells. When existing wells are to be modified extensively, including, but not limited to, replacing the casing, deepening the well, or changing the pump to increase the yield of the well by more than 25 gallons per minute, the well shall be modified to meet the minimum construction standards cited herein,