Washington Administrative Code › Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508) › Chapter 173-218 - Underground injection control program › Section 173-218-090 - Specific requirements for Class V wells to meet the nonendangerment standard

Current through Register Vol. 24-14, July 15, 2024
Specific requirements for Class V wells are organized by wells
				that are used for storm water management and wells that are used for other
				purposes. This section does not apply to the Class V wells in WAC
				173-218-100.
(1)
New
Class V UIC wells used
			 for
storm water management
must:
(a) Meet additional groundwater protection
			 area requirements as determined by other state laws or by local
			 ordinances;
(b) Not directly
			 discharge into groundwater. A separation between the bottom of the well and the
			 top of the groundwater is required. The treatment capacity of the unsaturated
			 zone or the zone where the fluid is discharged, and the pollutant loading of
			 the discharge must be considered when determining the vertical separation;
			 and
(c) The owner or operator of a
			 new Class V well used to manage storm water must meet the nonendangerment
			 standard as defined under WAC
			 173-218-080. The owner or
			 operator of a new Class V well must show compliance with the nonendangerment
			 standard prior to placing a new well into service. Compliance with the
			 nonendangerment standard may be met through one or a combination of the
			 following two approaches:
(i) Presumptive
			 approach: The presumptive approach means compliance with the nonendangerment
			 standard is presumed, unless discharge monitoring data or other site specific
			 information shows that a discharge causes or contributes to a violation of
			 chapter 173-200 WAC Water quality standards for groundwaters of the state of
			 Washington, when:
(A) The well activity is in
			 compliance with this chapter; and either
(B) The well is designed and installed to the
			 storm water manual current at the time of construction and is operated in
			 conformance with storm water best management practices including the proper
			 selection, implementation, and maintenance of all on-site pollution control
			 using the current storm water manual published by the department for your
			 region or an equivalent department approved local manual.
(C) Owners or operators of municipal separate
			 storm sewer systems regulated under section 1342(p) of the Federal Water
			 Pollution Control Act which also own or operate Class V UIC wells may satisfy
			 the presumptive approach by applying the storm water management programs
			 developed to comply with the Federal Water Pollution Control Act to their new
			 UIC wells. For new UIC wells, construction phase and postconstruction storm
			 water controls must be applied in accordance with applicable storm water
			 manuals.
(D) The presumptive
			 approach may not be used when best management practices do not exist to remove
			 or reduce a contaminant, the vadose zone has no treatment capacity and/or the
			 storm water quality is such that a best management practice does not exist to
			 reduce or eliminate the concentration.
(ii) Demonstrative approach: The
			 demonstrative approach means that the technical bases for the selection of
			 storm water best management practices are documented. The documentation must
			 include:
(A) The method and reasons for
			 choosing the storm water best management practices selected;
(B) The pollutant removal performance
			 expected from the practices selected;
(C) The technical basis supporting the
			 performance claims for the practices selected, including any available existing
			 data concerning field performance of the practices selected;
(D) An assessment of how the selected
			 practices will satisfy the requirements of WAC
			 173-218-080 and chapter 173-200
			 WAC; and
(E) An assessment of how
			 the selected practices will satisfy state requirements to use all known,
			 available, and reasonable methods of prevention, control and
			 treatment.