UIC Wells Classification

In Florida, there are six classes of injection wells.

Class I

Wells used to inject hazardous waste (new hazardous waste wells were banned in 1983), nonhazardous waste or municipal waste below the lowermost Underground Source of Drinking Water (USDW). There are more than 180 active Class I wells in Florida. The majority of the Class I injection facilities in Florida dispose of non-hazardous, secondary-treated effluent from domestic wastewater treatment plants. At locations where hydrogeologic conditions are suitable and where other disposal methods are not possible or may cause contamination, subsurface injection below all USDWs is considered a viable and lawful disposal method. There are favorable hydrogeologic conditions in Florida where the underground formations have the natural ability to accept and confine the waste. See an illustration of a Class I municipal well.

The injection wells are required to be constructed, maintained and operated so that the injected fluid remains in the injection zone, and the unapproved interchange of water between aquifers is prohibited. Class I injection wells are monitored so that if migration of injection fluids were to occur it would be detected before reaching the USDW. Permitting for these wells is done in our Tallahassee office. Testing is conducted on all Class I injection wells at a minimum of every five years to determine that the well structure has integrity.

Financial Responsibility

The UIC program requires applicants for Class I wells to assure, through a performance bond or other appropriate means, that resources necessary to plug and abandon the wells are available. Financial responsibility may cover post-closure monitoring and any corrective action resulting from this monitoring. Guidance for the financial responsibility requirements can be found at "Financial Responsibility Options for Owners and Operators of Injection Wells." (This document has been scanned from an old hard copy source that has not yet been converted electronically. The information is current. If you have difficulty reading the guidance, please call the UIC program at 850-245-8645 and we will  provide a hard copy.)

Local Government Guarantee

Another financial responsibility option for local governments only can be found in Local Government Guarantee document. As part of the Local Government Guarantee, the local government must submit a Form for Certification of Financial Responsibility for Local Government (updated in 2014), which certifies unconditionally the obligation of the local government to perform plugging and abandonment of its injection system(s) pursuant to Chapter 62-528, F.A.C. The certification form provides information on the location of the injection system(s) guaranteed by the local government with the related cost estimates for plugging and abandonment. 

Class II

Wells used to inject fluids associated with the production of oil and natural gas or fluids used to enhance hydrocarbon recovery. Class II injection wells are regulated by the Florida Department of Environmental Protection, Oil and Gas Program.

Class III

Wells that inject fluids for extraction of minerals (none in Florida).

Class IV

Wells or septic systems that are used to dispose of hazardous or radioactive wastes into or above a USDW. (Banned in Florida.)

Class V

Class V injection wells are wells not included Classes I through IV, and VI. Class V wells are used for the storage or disposal of fluids into or below a USDW. The fluid injected must meet appropriate criteria as determined by the classification of the receiving aquifer. Common types of Class V wells include air conditioning return flow wells, swimming pool drainage wells, stormwater drainage wells, lake level control wells, domestic waste wells, and aquifer storage and recovery (ASR) wells (see below). There are more than 13,000 Class V wells in Florida. (See below for differentiation of major and non-major Class V wells.)

Major vs. Non-Major Class V Wells

Major Class V wells are permitted through our Tallahassee office. These wells include all ASR wells, aquifer recharge, exploratory and reverse osmosis wells. They also include domestic waste wells completed in a USDW.

Non-Major Class V wells are permitted through our district offices. These wells include domestic wastewater wells below the USDW, closed loop heat pump/air conditioning return flow wells, swimming pool drainage wells, stormwater wells and remediation wells.

Aquifer storage and recovery (ASR)

Aquifer storage and recovery (ASR) is a mechanism for storing water underground through an injection well to be withdrawn in the future for beneficial purposes. Typically, water is stored during times of excess supply for use when supplies are limited. ASR wells are capable of storing treated drinking water as well as reclaimed water, surface water or groundwater. However, whether treated or not, water injected into ASR wells must meet Florida's drinking water quality standards. The level of treatment required after storage depends on the use of the water, whether for public consumption, surface water augmentation, wetlands enhancement, irrigation, saltwater intrusion barrier, etc. Because ASR provides for the storage of water that would otherwise be lost to tide or evaporation, it represents a crucial water supply management strategy for Florida’s future. See a simplified depiction of an ASR well.

Class VI

Wells used to inject carbon dioxide, captured from industrial processes such as power plants, for storage into the subsurface. The U.S. Environmental Protection Agency regulates this class of wells in Florida (none in Florida).

Additional Information

• Get an illustration of the various classes of injection wells.
• Get a map of Class I and Class V injection wells on Map Direct.

Monthly Operation Reports

Monthly operation reports are required for facilities that report injection and monitor well physical and chemical characteristics. These reports should be submitted to both the Tallahassee and appropriate district offices. Electronic submittal of the reports and laboratory reports is encouraged. The electronic mailbox for Tallahassee is Tal_UIC@FloridaDEP.gov; each district office has its own electronic mailbox or email address. The department is in the process of creating reporting templates for facilities. View Helpful Tips for Completing the Underground Injection Control Monthly Operating Report.