R18-9-A606. Criteria for Exempted Aquifers

An aquifer or a portion thereof which meets the criteria for an “USDW” in R18-9-A601(70) may be determined under R18-9- A605 to be an “exempted aquifer” for Class I-V wells if it meets the criteria in subsections (A)(1) through (A)(3). Class VI wells must meet the criteria under subsection (A)(4). 1. It does not currently serve as a source of drinking water; and 2. It cannot now and will not in the future serve as a source of drinking water because: a. It is mineral hydrocarbon or geothermal energy producing, or can be demonstrated by a permit applicant as part of a permit application for a Class II or Class III operation to contain minerals or hydrocarbons that considering their quantity and location are expected to be commercially producible; b. It is situated at a depth or location which makes recovery of water for drinking water purposes economically or technically impractical; c. It is so contaminated that it would be economically or technologically impractical to render that water fit for human consumption; or d. It is located over a Class III well mining area subject to subsidence or catastrophic collapse; or 3. The total dissolved solids content of the ground water is more than 3,000 and less than 10,000 mg/l and it is not reasonably expected to supply a public water system. 4. The areal extent of an aquifer exemption for a Class II enhanced oil recovery or enhanced gas recovery well may be expanded for the exclusive purpose of Class VI injection for geologic sequestration under R18-9-A605(D) if it meets the following criteria: a. It does not currently serve as a source of drinking water; and b. The total dissolved solids content of the ground water is more than 3,000 mg/l and less than 10,000 mg/l; and c. It is not reasonably expected to supply a public water system.