USEPA Region 2 List of Injection Well Classes & Types https://www.epa.gov/uic/underground-iniection-control-well-classes Class I - Industrial and Municipal Waste Disposal Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 1H Hazardous Industrial N/A N/A 11 Non-Hazardous Industrial N/A N/A 1M Municipal N/A N/A 1R Radioactive Waste Disposal N/A N/A 1W Drinking Water Treatment Residual Depending on the well class assigned by the state or Direct Implementation (Dl) Region, Drinking Water Treatment Residuals could be Class 1W, 2W, or 5A23. N/A IX Other N/A N/A https://www.epa.gov/uic/class-i-industrial-and-municipal-waste-disposal-wells Class II - Oil and Gas Related Injection Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 2A Annular Disposal N/A N/A 2D Produced Fluid Disposal N/A N/A 2F Hydraulic Fracturing with Diesel Fuel N/A N/A 2H Hydrocarbon Storage N/A N/A 2M Coal Bed Methane Hydro-fracturing wells N/A N/A 2R Enhanced Recovery N/A N/A 2W Drinking Water Treatment Residual Depending on the well class assigned by the state or Dl Region, Drinking Water Treatment Residuals could be Class 1W, 2W, or 5A23. N/A 2X Other N/A N/A https://www.epa.gov/uic/class-ii-oil-and-gas-related-iniection-wells SOURCE: Prepared by USEPA Region 2 February 2, 2022. Page 1 of 6 ------- USEPA Region 2 List of Injection Well Classes & Types, continued. Class III - Solution Mining Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 3A Salt Solution Mining N/A N/A 3C Copper Mining N/A N/A 3G In Situ Gasification N/A N/A 3N Nahcolite Mining N/A N/A 3S Sulfur Mining N/A N/A 3U Uranium Mining N/A N/A 3X Other Minerals N/A N/A https://www.epa.gov/uic/class-iii-iniection-wells-solution-mining Class IV - Shallow Hazardous and Radioactive Waste Injection Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 4A Authorized as part of RCRA or CERCLA cleanup N/A N/A 4P Prohibited activity N/A N/A https://www.epa.gov/uic/class-iv-shallow-hazardous-and-radioactive-iniection-wells Class VI - Geologic Sequestration Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 6A C02 Sequestration - subtype 1 N/A N/A 6B C02 Sequestration - subtype 2 N/A N/A https://www.epa.gov/uic/class-vi-wells-used-geologic-sequestration-co2 Page 2 of 6 ------- USEPA Region 2 List of Injection Well Classes & Types, continued. Class V - Wells that inject non-hazardous fluids into or above underground sources of drinking water Class V Industrial Wells - Wells, or cesspools and septic systems, used to inject fluids from industrial sources Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5A1 Industry - Carwashes Carwashes N/A 5A2 Industry - Carwashes where no engine or undercarriage washing is performed Carwashes where no engine or undercarriage washing is performed N/A 5 A3 Industry - Appliance service and repair facilities Appliance service and repair facilities N/A 5A4 Industry - Beauty Shops / Barber Shops Beauty Shops/ Barber Shop N/A 5A5 Industry - Nail salons Nail salons N/A 5A6 Industry - Dry cleaners Dry cleaners N/A 5A7 Industry - Laundromats where no on-site dry cleaning is performed Laundromats where no on-site dry cleaning is performed N/A 5A8 Industry - Funeral services Funeral services N/A 5A9 Industry - Wood / Furniture finishing facilities Wood / Furniture finishing facilities N/A 5A10 Industry - Machine and welding shops Machine and welding shops N/A 5A11 Industry - Medical service facilities Medical service facilities N/A 5A12 Industry - Pesticide application service facilities Pesticide application service facilities N/A 5A13 Industry - Photographic processing facilities Photographic processing facilities N/A 5A14 Industry - Printing facilities Printing facilities N/A 5A15 Industry - Veterinary, kennel and pet grooming service facilities Veterinary, kennel and pet grooming service facilities N/A 5A16 Industry - Metal plating / fabrication facilities Metal plating / fabrication facilities N/A 5A17 Industry - Equipment manufacturing / repair plants Equipment manufacturing / repair plants N/A 5A18 Industry - Cooling water with no additives Cooling water with no additives N/A 5A19 Industry - Cooling water with additives Cooling water with additives N/A Page 3 of 6 ------- USEPA Region 2 List of Injection Well Classes & Types, continued. Continued: Class V Industrial Wells - Wells, or cesspools and septic systems, used to inject fluids from industrial sources Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5A20 Industry - Food processing operations Food processing operations N/A 5A21 Industry - Small engine repair shops Small engine repair shops N/A 5A23 Drinking Water Treatment Residual Depending on the well class assigned by the state or Dl Region, Drinking Water Treatment Residuals could be Class 1W, 2W, or 5A23. N/A 5A24 Industry - Other Any other wells used to inject non-hazardous wastewaters generated by industrial, commercial, and service establishments and that are not included in one of the above categories N/A 5A25 Air Scrubber Waste Disposal Wells N/A N/A 5A26 Water Softener Regeneration Brine Disposal Wells N/A N/A Class V Motor Vehicle Waste Disposal Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5J Waste Discharge Well N/A N/A 5K Motor Vehicle Waste Disposal Wells used to inject fluids from motor vehicle repair or maintenance activities, such as an auto body repair shop, automotive repair shop, car dealership, specialty repair shop (e.g., transmission and muffler repair shop), or any facility that does any vehicular repair work 5X28 (Automobile Service Station Disposal) Class V Beneficial Use Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5B1 Beneficial Use - Aquifer recharge Aquifer recharge 5R21 (Aquifer Recharge) 5B2 Beneficial Use - Salt water intrusion barrier Salt water intrusion barrier 5B22 (Saline Water Intrusion Barrier) 5B3 Beneficial Use - Subsidence control Subsidence control 5S23 (Subsidence Control) 5B4 Beneficial Use - Aquifer storage and recovery Aquifer storage and recovery Not addressed as separate category 5B6 Beneficial Use - Subsurface environmental remediation Subsurface environmental remediation 5X26 (Aquifer Remediation Related) Page 4 of 6 ------- USEPA Region 2 List of Injection Well Classes & Types, continued. Class V Fluid Return Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5C1 Fluid Return - Spent-brine Return Flow Wells used to inject spent brines after the extraction of minerals from produced fluids 5X16 (Spent-brine Return Flow) 5C2 Fluid Return - Heat Pump/Air Conditioning Return Flow Wells used to inject heat pump return fluids 5A7 (Heat Pump/Air Conditioning Return Flow) 5C3 Fluid Return - Direct Heat Return N/A 5A6 (Direct Heat Return) 5C4 Fluid Return - Electric Power Return Wells used to inject fluids that have undergone chemical alteration during the production of geothermal energy for heating, aquaculture, or production of electric power 5A5 (Electric Power Return) 5C5 Fluid Return - Ground Water Aquaculture Return Flow Wells used to inject fluids that have undergone chemical alteration during the production of geothermal energy for heating, aquaculture, or production of electric power 5A8 (Ground Water Aquaculture Return Flow) Class V Domestic Wastewater Disposal Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5D Sewage Treatment Effluent Wells used to inject treated effluent from POTWs, or privately owned treatment works receiving solely sanitary waste 5W12 (Domestic Wastewater Treatment Plant Effluent Disposal) 5E Cesspools Cesspools having the capacity to serve 20 persons or more per day and used solely for the subsurface emplacement of sanitary waste 5W9 (Untreated Sewage Waste Disposal), 5W10 (Cesspools) 5F Septic Systems Septic tank with subsurface fluid distribution system and/or dry wells having the capacity to serve 20 persons or more per day and used solely for the subsurface emplacement of sanitary waste 5W11 (Septic Systems - Undifferentiated Disposal), 5W32 (Septic Systems - Drainfield Disposal), 5W31 (Septic Systems - Well Disposal) Class V Experimental Technology Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5G1 Experimental Technology - Other N/A 5X25 (Other Experimental Technology) 5G2 C02 Sequestration Experimental geologic sequestration technology wells used for experimental purposes * C02 Sequestration Page 5 of 6 ------- USEPA Region 2 List of Injection Well Classes & Types, continued. Class V Drainage Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5H1 Stormwater Drainage Wells used to drain surface and subsurface fluids, including stormwater runoff and agricultural drainage that may have the potential to receive insignificant amounts of waste due to small volume leaks, drips, or spills 5D2 (Stormwater Drainage) 5H2 Agricultural Drainage Wells used to drain surface and subsurface fluids, including stormwater runoff and agricultural drainage that may have the potential to receive insignificant amounts of waste due to small volume leaks, drips, or spills 5F1 (Agricultural Drainage) 5H3 Drainage - Other Wells used to drain surface and subsurface fluids, including stormwater runoff and agricultural drainage that may have the potential to receive insignificant amounts of waste due to small volume leaks, drips, or spills Other Class V In-Situ Solution Mining Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 5 LI Solution Mining Wells used to inject fluids for the purpose of producing minerals or energy, which are not Class II or III wells 5X14 (Solution Mining) 5L2 In situ Fossil Fuel Recovery Wells used to inject fluids for the purpose of producing minerals or energy, which are not Class II or III wells. Deep-wells injection: 5L2 5X15 (In situ Fossil Fuel Recovery) Class V Miscellaneous Wells Well Type Code Category of Well Description of Category Corresponding Injection Well Type in 1987 Report to Congress 51 Mine Backfill and Drainage Wells used to inject materials into mined out portions of subsurface mines, whether what is injected is a radioactive waste or not, including: (1) slurries of sand, gravel, cement, mill tailings/refuse, fly ash, or other solids, and (2) mine drainage 5X13 (Mining, Sand, or Other Backfill) 5X Other Class V Well N/A N/A https://www.epa.gov/uic/class-v-wells-iniection-non-hazardous-fluids-or-above-underground-sources-drinking-water Page 6 of 6 ------- |