[Title 40 CFR 144.6]
[Code of Federal Regulations (annual edition) - July 1, 2009 Edition]
[Title 40 - PROTECTION OF ENVIRONMENT]
[Chapter I - ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)]
[Subchapter D - WATER PROGRAMS (CONTINUED)]
[Part 144 - UNDERGROUND INJECTION CONTROL PROGRAM]
[Subpart A - General Provisions]
[Sec. 144.6 - Classification of wells.]
[From the U.S. Government Printing Office]


40PROTECTION OF ENVIRONMENT222009-07-012009-07-01false144.6Sec. 144.6PROTECTION OF ENVIRONMENTENVIRONMENTAL PROTECTION AGENCY (CONTINUED)WATER PROGRAMS (CONTINUED)UNDERGROUND INJECTION CONTROL PROGRAMGeneral Provisions
Sec. 144.6  Classification of wells.

    Injection wells are classified as follows:
    (a) Class I. (1) Wells used by generators of hazardous waste or 
owners or operators of hazardous waste management facilities to inject 
hazardous waste beneath the lowermost formation containing, within one-
quarter mile of the well bore, an underground source of drinking water.
    (2) Other industrial and municipal disposal wells which inject 
fluids beneath the lowermost formation containing, within one quarter 
mile of the well bore, an underground source of drinking water.
    (3) Radioactive waste disposal wells which inject fluids below the 
lowermost formation containing an underground source of drinking water 
within one quarter mile of the well bore.
    (b) Class II. Wells which inject fluids:
    (1) Which are brought to the surface in connection with natural gas 
storage operations, or conventional oil or natural gas production and 
may be commingled with waste waters from gas plants which are an 
intergral part of production operations, unless those waters are 
classified as a hazardous waste at the time of injection.
    (2) For enhanced recovery of oil or natural gas; and
    (3) For storage of hydrocarbons which are liquid at standard 
temperature and pressure.
    (c) Class III. Wells which inject for extraction of minerals 
including:
    (1) Mining of sulfur by the Frasch process;
    (2) In situ production of uranium or other metals; this category 
includes only in-situ production from ore bodies which have not been 
conventionally mined. Solution mining of conventional mines such as 
stopes leaching is included in Class V.
    (3) Solution mining of salts or potash.
    (d) Class IV. (1) Wells used by generators of hazardous waste or of 
radioactive waste, by owners or operators of hazardous waste management 
facilities, or by owners or operators of radioactive waste disposal 
sites to dispose of hazardous waste or radioactive waste into a 
formation which within one-quarter (\1/4\) mile of the well contains an 
underground source of drinking water.
    (2) Wells used by generators of hazardous waste or of radioactive 
waste, by owners or operators of hazardous waste management facilities, 
or by owners or operators of radioactive waste disposal sites to dispose 
of hazardous waste or radioactive waste above a formation which within 
one-quarter (\1/4\) mile of the well contains an underground source of 
drinking water.
    (3) Wells used by generators of hazardous waste or owners or 
operators of hazardous waste management facilities to dispose of 
hazardous waste, which cannot be classified under paragraph (a)(1) or 
(d) (1) and (2) of this section (e.g., wells used to dispose of 
hazardous waste into or above a formation which contains an aquifer 
which has been exempted pursuant to Sec. 146.04).
    (e) Class V. Injection wells not included in Class I, II, III, or 
IV. Specific types of Class V injection wells are described in Sec. 
144.81.

[48 FR 14189, Apr. 1, 1983, as amended at 52 FR 20676, June 2, 1987; 64 
FR 68565, Dec. 7, 1999]