Underground Injection Control Program

Kansas is one of 34 states that manage the Class I-V Underground Injection Control (UIC) program for the U.S. Environmental Protection Agency (EPA) through geologists that work for the Kansas Department of Health and Environment (KDHE) and the Kansas Corporation Commission (KCC). KDHE regulates Classes I, III, and V injection wells. A complete list of permitted UIC Class I wells can be found on the Kansas Geological Survey (KGS) Fluid Injection Database.

  1. Well Classes
  2. Earthquakes
  3. Regulations
  4. Resources

Well Class Descriptions


Class I Wells: Used to inject hazardous and non-hazardous industrial and municipal wastewater into deep, confined rock formations. Disposal typically occurs thousands of feet below the lower most underground source of drinking water (USDW). Class I wells are highly technical with many layers of protection between the USDW and the injected waste and have many regulatory tests and monitoring requirements to maintain compliance. The wastewater disposed of in Class I wells cannot be feasibly treated, stored, or disposed by other methods.

  • Industries that utilize Class I wells: refining, metal production, chemical manufacturing, pharmaceutical industry, commercial disposal, food production, and municipal wastewater treatment.
  • Kansas has the 3rd most Class I injection wells in the country.
  • Nearly all Kansas Class I disposal wells inject into the Arbuckle Formation, which also has the majority of withdrawal and injection from Class II wells.

Class II Wells: Wells used to inject fluids, primarily brines, associated with oil and natural gas production into deep confined rock formations. These wells are constructed similarly to Class I wells, but are regulated by the KCC.

Class III Wells: Wells used to inject fluids for the dissolution and extraction of minerals. Most of the Class III wells managed by KDHE are operated by well-known international salt companies.

  • Kansas has the 6th largest Class III inventory.
  • Operators in Kansas perform sonar and gamma logs to help maximize extraction of the resource while staying in regulatory compliance. Kansas regulates the well to ensure no contamination of the USDW occurs during the mining process and regulates the caverns to help prevent sinkholes and collapses.

Class IV Wells: Shallow wells used to dispose of hazardous or radioactive wastes into or above formations that contain groundwater. In 1984, the U.S. EPA banned the use of Class IV injection wells.

Class V Wells: Used in inject non-hazardous fluids underground, i.e. storm water drainage wells, septic system leach fields, and groundwater remediation wells.

Class VI Wells: Wells that inject carbon dioxide for long term storage, also known as sequestration, these wells are regulated by the U.S. EPA, Region 7.