CLASSES

(INJECTION WELL) Classifications of the U.S. Environmental Protection Agency (EPA) that determine the permit requirements of an Injection Well. The following classes apply: (1) Class I: A well into which liquid hazardous wastes or other fluids are pumped down, with the fluids being injected into an underground formation below the lowest underground source of drinking water that is within a one-quarter mile radius of the well; (2) Class II: A well used to dispose of fluids produced by oil and gas wells, to introduce fluids for enhanced oil recovery, or for liquid hydrocarbon storage; (3) Class III: A well used to pump fluids underground for mineral extraction; (4) Class IV: A well used to re-inject treated fluid from a superfund cleanup site into or above an underground formation within a one-quarter mile radius of the well; (5) Class V: Wells not included in Classes I-IV, mainly shallow industrial disposal wells or Recharge Wells.