South Dakota
Underground injection wells
Injection wells in South Dakota fall under the underground injection control (UIC) program, which regulates putting waste into the subsurface. The South Dakota Department of Agriculture and Natural Resources (DANR) says anyone operating an injection well of any type must notify it. DANR regulates the Class II wells used in oil and gas work, through its Minerals, Mining, and Superfund Program. EPA regulates the other classes allowed in the state, though DANR's approval is also needed for some septic systems.
In a Phase I ESA
ASTM E1527-21 does not name injection well lists among its standard record sources, so no search distance attaches to them under the standard. An injection or disposal well at or near a property still says something about how waste or fluids were handled there. The first question is which agency has the record. DANR's permitting guide sorts the classes this way:
| Class | What DANR's guide says it is | Who regulates it in South Dakota |
|---|---|---|
| Class I | Hazardous and municipal waste disposal wells | Banned in the state |
| Class II | Wells for disposing of oil and gas production waste or for enhanced recovery | DANR |
| Class III | Wells for extracting minerals by solution mining | EPA |
| Class IV | Shallow hazardous waste injection wells | Banned in the state |
| Class V | Among others, wells returning geothermal water, wells disposing of domestic wastewater (septic systems), and wells used to clean up groundwater | EPA |
| Class VI | Wells for geologic sequestration of carbon dioxide | EPA |
Three South Dakota details shape the search.
- Some septic systems count. DANR's guide says a septic system serving more than 20 people that qualifies as a Class V well also needs DANR's notification and approval, while one serving 20 or fewer does not need notification. A note to the guide's table adds that a septic drain field used for wastes other than domestic wastewater needs an underground injection control permit. A drain field at a shop or plant is worth asking about for that reason.
- Class II wells need a permit to inject. DANR says any injection for enhanced oil recovery or for disposing of exploration and production waste needs a permit to inject, under SDCL 45-9 and ARSD article 74:12. The application goes with a petition under DANR's Notice of Recommendation procedure. See Oil and Gas Permits for the well records.
- An aquifer exemption needs EPA. DANR says it holds primary enforcement authority for Class II wells in the state, but that every aquifer exemption must be approved by EPA, because the exemption relieves part of an aquifer from the federal Safe Drinking Water Act. Under ARSD 74:12:07:24, as DANR's page cites it, a portion of an aquifer can be exempted only if it does not serve as a drinking water source now, holds water with between 3,000 and 10,000 mg/L of total dissolved solids, and meets other conditions.
The rules DANR's guide lists are SDCL 45-9 and ARSD 74:12:07 for Class II, and 40 CFR parts 144 to 147 for the classes EPA regulates.
Where to look a site up
- For Class II wells, DANR's Data & Mapping page links an Oil, Gas and Injection Well Database, which this handbook did not open. The Minerals, Mining, and Superfund Program is at (605) 773-4201.
- For Class V wells, DANR's guide sends readers to EPA Region 8 at (303) 312-6312 and to EPA's Class V injection wells page.
Getting the file
DANR's page footer links Request Public Records, an address on the state's sd.gov portal that this handbook did not open. The pages read do not say where Class II well files are kept for public review or what a request must include. For the classes EPA regulates, ask EPA.
Sources
South Dakota Department of Agriculture and Natural Resources pages, read October 13, 2026:
- One-Stop Permitting and Regulation Guide (2025 Edition) | SD DANR, no modified date shown; its opening letter is dated July 2026.
- South Dakota Minerals and Mining Program - Oil and Gas Data and Reports, no modified date shown.
- South Dakota Minerals and Mining Program - Oil and Gas, no modified date shown.
- South Dakota Minerals and Mining Program, no modified date shown.
- DANR / Data & Mapping, no modified date shown.