Well construction as described in this section may be used for private and reasonable domestic use wells and for noncommercial livestock watering wells as an alternative to the construction required by § 74:02:04:28. All other wells, including public water supply wells, shall be constructed as required by § 74:02:04:28. If any of the following requirements cannot be met, the well construction must comply with the requirements of § 74:02:04:28. The following alternative well construction may be used to construct and complete wells into the Inyan Kara group if the top of the Inyan Kara is more than 1,000 feet below the land surface. The Inyan Kara group includes the Fall River and the Lakota. The alternative well construction may be used if the following requirements are met:

1. (1) Surface casing is installed and pressure-grouted with cement grout to a depth of at least 300 feet or into an unweathered clay or shale formation, whichever depth is greater;
2. (2) The drill bit used to drill into the production aquifer is no larger than four and one-half inches in diameter;
3. (3) The size of the production casing installed below the grouted surface casing down to and the screen installed in the production aquifer is no larger than two inches in diameter;
4. (4) The production casing material installed below the surface casing and down to the production formation is type K hard copper, schedule 80 thermoplastic, brass, or stainless steel. The casing may not be installed under conditions that exceed the manufacturer's recommendations;
5. (5) Depending upon local conditions, packers and other construction techniques may be used that result in sealing the annulus between the drill hole and the casing above the production aquifer. The well driller shall construct the well to prevent movement of mud, silt, or other aquifer water into the production aquifer well. Packers made from burlap bags, gunny sacks, or similar materials are prohibited;
6. (6) The production casing and packers are not installed unless the weight of the drilling fluid is heavy enough to overcome aquifer pressures; and

7. (7) Only one casing is placed into the production aquifer of a new well. New wells double-cased into the production aquifer are prohibited. However, if the original casing becomes defective, the well may be rehabilitated by placing new casing inside the old defective casing.

   See Appendix G at the end of this chapter.

   Note: Although this type of well construction may be less expensive below the cement-grouted surface casing, it is more likely to fail than a well constructed and grouted pursuant to § 74:02:04:28. The success of this type of well construction is dependent upon the shale above the production aquifer sloughing off and filling and sealing the drill hole annulus outside the casing to prevent movement of high-pressure production aquifer water outside the casing, movement of other aquifer water, mud, or silt into the production aquifer, or movement of other aquifer water between aquifers.

Source: 12 SDR 50, effective September 29, 1985; 13 SDR 129, 13 SDR 141, effective July 1, 1987; 18 SDR 224, effective July 16, 1992.

General Authority: SDCL 46-2-5 , 46-6-20 , 46-6-27.

Law Implemented: SDCL 46-6-6.1 , 46-6-10 , 46-6-20 , 46-6-27.