Washington Administrative Code
Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508)
Chapter 173-218 - Underground injection control program
Section 173-218-040 - UIC well classification including allowed and prohibited wells
Current through Register Vol. 24-06, March 15, 2024
The most common type of UIC well in Washington is a Class V well. A Class V well is usually a shallow disposal well such as a drywell, drainfield or French drain (see subsection (5) of this section).
(1) "Class I injection well" means a well used to inject dangerous and/or radioactive waste, beneath the lowermost formation containing an underground source of drinking water within one-quarter mile of the well bore. All Class I wells are prohibited in Washington and must be decommissioned.
(2) "Class II injection well" means a well used to inject fluids:
(3) "Class III injection well" means a well used for extraction of minerals. All Class III wells are prohibited in Washington and must be decommissioned. Examples of Class III injection wells include, but are not limited to, the injection of fluids for:
(4) "Class IV injection well" means a well used to inject dangerous or radioactive waste into or above an underground source of drinking water. Class IV wells are prohibited and must be decommissioned except for Class IV wells reinjecting treated groundwater into the same formation from where it was drawn as part of a removal or remedial action if such injection is approved by EPA in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act or the Resource Conservation and Recovery Act, 40 C.F.R. 144.13(c). Other examples of Class IV wells include:
(5) "Class V injection well" means all injection wells not included in Classes I, II, III, or IV. Class V wells are usually shallow injection wells that inject fluids above the uppermost groundwater aquifer. Some examples are dry wells, French drains used to manage storm water and drain fields.
Statutory Authority: Chapter 80.80 RCW. 08-14-011 (Order 07-11), § 173-218-040, filed 6/19/08, effective 7/20/08. Statutory Authority: Chapters 43.21A and 90.48 RCW. 06-02-065 (Order 01-10), § 173-218-040, filed 1/3/06, effective 2/3/06. Statutory Authority: RCW 43.21A.445. 84-06-023 (Order DE 84-02), § 173-218-040, filed 2/29/84.