250 R.I. Code R. 250-RICR-150-05-4.6

Current through November 7, 2024

Section 250-RICR-150-05-4.6 - Underground Injection Control (UIC) Program

A. The Underground Injection Control Program is a federally delegated program administered by the Department and the U.S. Environmental Protection Agency (EPA) under the federal Safe Drinking Water Act and is designed to protect groundwater resources from the subsurface disposal of hazardous and non-hazardous wastewater or other fluid through injection wells. The following classifications are used to define the six classes of injection wells regulated by the program based on their use and are described below for informational purposes. Note: Classes I-III injection wells are prohibited in Rhode Island; Class IV injection wells are allowed only in accordance with § 4.10(A)(2) of this Part; Class V wells include injection wells other than Classes I-IV and, with Class IV wells, are groundwater discharge systems subject to all requirements of these rules.

B. Class I wells are used by generators of hazardous waste or owners or operators of hazardous waste management facilities to inject hazardous waste; by municipalities to inject municipal wastewater; by industries to inject non-hazardous industrial waste; and, for injection of radioactive fluids. These are deep wells that inject fluids below the lowermost formation containing groundwater.

C. Class II wells are used to inject fluids that are brought to the surface in connection with natural gas storage operations or conventional oil or natural gas production; to enhance recovery of oil or natural gas; and, for storage of hydrocarbons that are liquid at standard temperature and pressure.

D. Class III wells are used to inject fluids for the extraction of minerals including mining of sulfur by the Frash process; in-situ production of uranium or other metals from ore bodies that have not been conventionally mined; and, for the solution mining of salts or potash.

E. Class IV wells are used to inject hazardous or radioactive waste into or above the lowermost formation containing groundwater; to discharge solutions to remediate contamination in-situ; or, to discharge contaminated groundwater that has been treated and is being discharged into the same formation from which it was drawn, pursuant to provisions of clean-up of releases under the federal CERCLA or RCRA programs or state clean-up program delegated these federal authorities.

F. Class V wells are those wells not included in Classes I-IV that inject wastewater or other fluid, other than hazardous waste, directly below the ground surface and have a variety of uses including but not limited to the following:

1. Wells used to inject water into an aquifer to replenish the aquifer;

2. Wells used to store potable water in an aquifer and to recover the stored water from the same well for beneficial use;

3. Wells used to inject water into fresh water aquifers to prevent intrusion of salt water into fresh water;

4. Wells used to discharge a mixture of water and sand, mill tailings or other materials into mined-out portions of underground mines;

5. Wells used to inject fluid into a non-oil or gas-producing zone to reduce, eliminate or control subsidence;

6. Wells used to discharge spent geothermal fluid associated with the extraction of heat, or as a heat sink to carry off excess heat when cooling buildings, through a ground-source heat pump/air conditioning system or direct-heat application; or, for the production of electric power;

7. Wells used to discharge a variety of non-contact water that contains no additives and has not been chemically altered (e.g. cooling water, water from water supply treatment testing, filter backwash, boiler blowdown, etc.);

8. Wells used to discharge a variety of fluids that cannot otherwise be classified as agricultural, industrial or stormwater;

9. Wells used to drain rainwater and melted snow from impervious surfaces;

10. Wells used to discharge fluids from floor drains or sinks in areas where motor vehicle repair, maintenance or service activities occur (this activity is prohibited);

11. Wells used for beneficial purposes associated with the control of groundwater contamination, including, for example, the introduction of remedial agents into contaminated aquifers to neutralize the contamination, to increase groundwater flow through a contaminant zone in an aquifer to aid contaminant removal, to form hydraulic barriers to contain a contaminant plume or to re-inject treated groundwater from an on-site pump-and-treat system;

12. Wells used to discharge motor vehicle washwater that was used to wash only the exterior of vehicles;

13. Wells used to test new technologies, if the technology cannot be considered under an established well subclass (e.g., a pilot test related to geologic sequestration of carbon dioxide would be considered experimental, however, a well-used for experimental bioremediation would be classified as aquifer remediation); and,

14. Wells used to discharge wastewater resulting from a variety of commercial, industrial or institutional processes or activities (e.g. water from equipment washing, process and non-process cooling water, etc.).

G. Class VI wells are used to inject carbon dioxide (CO2) into underground subsurface rock formations for long-term storage, or geologic sequestration. Geologic sequestration refers to a suite of technologies that may be deployed to reduce CO2 emissions to the atmosphere to help mitigate climate change.

250 R.I. Code R. 250-RICR-150-05-4.6