037-4 Wyo. Code R. § 4-3
(a) When a water well is to be rehabilitated to increase efficiency, all equipment used shall be clean and as sterile as possible to prevent well to well or well to aquifer cross-contamination. All chemical or biological agents to be introduced into a well shall meet ASTM, API, NSF and/or AWWA standards approved for the application of well rehabilitation. Physical rehabilitation of the well including jetting, scrubbing, bailing, etc. shall be performed in a manner that does not compromise the integrity of the well casing materials, filter pack, and grout materials. When acidizing or flocculating agents are pumped or removed from a well, it may be necessary to obtain clearance from the Wyoming Department of Environmental Quality - Water Quality Division (WDEQ-WQD) for the surface discharge of these agents.
(b) If, in the repair of a well, the old casing is withdrawn, the well shall be recased in conformance with these rules.
(c) If a liner is installed to prevent leakage of undesirable water into a well, the annular space between the casing and liner shall be completely sealed by packers, casing swedging, pressure grouting, or other methods which will prevent the movement of water between the casing and liner.
037-4 Wyo. Code R. § 4-3