Current through Register Vol. 24-06, March 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.
(2)
Existing Class V UIC wells
used for storm water management do not have to meet the new well
requirements. If the UIC wells are not already registered, the owner or
operator must register the wells with the department and complete a well
assessment. The following timelines must be met unless otherwise approved from
the department:
(a) If you own or operate less
than or equal to fifty wells:
(i) You have
three years after the adoption date of this rule to register your UIC wells
unless an extension has been approved by the department;
(ii) You have five years after the adoption
date of this rule to complete a well assessment. The approach to conducting the
well assessment will be determined by the owner. The well assessment evaluates
the potential risks to groundwater from the use of UIC wells and includes
information such as the land use around the well which may affect the quality
of the discharge and whether the UIC well is located in a groundwater
protection area. It may include the local geology, and depth of the groundwater
in relation to the UIC well if the well is considered a high threat to
groundwater. The well assessment requirements will be met if an owner or
operator applies the storm water best management practices contained in a
guidance document approved by the department to their UIC wells and determines
if the UIC well is located in a groundwater protection area;
(iii) Any well assessment that identifies a
well as a high threat to groundwater must include a retrofit schedule;
and
(iv) You must immediately take
action to correct the use of a well that is determined to be an imminent public
health hazard, for example when a drinking water supply is contaminated and
causes a public health emergency. The department must be notified within thirty
days from the determination and may determine a retrofit schedule. The
department's enforcement procedure (see WAC
173-218-130 ) will be followed
when a retrofit schedule is needed.
(b) If you own or operate more than fifty
wells:
(i) You have five years after the
adoption date of this rule to register your UIC wells unless an extension has
been approved from the department;
(ii) You have seven years after the adoption
date of this rule to complete a well assessment. The approach to conducting the
well assessment will be determined by the owner. The well assessment evaluates
the potential risks to groundwater from the use of UIC wells and includes
information such as the land use around the well which may affect the quality
of the discharge, and whether the UIC well is located in a groundwater
protection area. It may include the local geology, and depth of the groundwater
in relation to the UIC well if the well is considered a high threat to
groundwater. The well assessment requirements will be met if an owner or
operator applies the storm water best management practices contained in a
guidance document approved by the department to their UIC wells and determines
if the UIC well is located in a groundwater protection area;
(iii) Any well assessment that identifies a
well as a high threat to groundwater must include a retrofit schedule;
and
(iv) You must immediately take
action to correct the use of a well that is determined to be an imminent public
health hazard, for example when a drinking water supply is contaminated and
causes a public health emergency. The department must be notified within thirty
days from the determination and may establish a retrofit schedule. The
department's enforcement procedure will be followed when a retrofit schedule is
needed.
(c) If you own
or operate a site that uses, stores, loads, or treats hazardous substances or
is an industrial facility that has a Standard Industrial Classification as
regulated by Federal Regulations, 40 C.F.R. Subpart 122.26 (b)(14) (excluding
construction sites), you may use the following to satisfy the documentation
requirements for meeting the nonendangerment standard:
(i) If the facility has or will have a waste
water discharge permit issued pursuant to
chapter
90.48 RCW, including a
National Pollutant Discharge Elimination System (NPDES) permit, the associated
storm water pollution prevention plan may be used in place of the well
assessment to meet the nonendangerment standard provided the storm water
pollution prevention plan specifically addresses storm water discharges to UIC
wells; or
(ii) For unpermitted
facilities, the preparation and implementation of a storm water pollution
prevention plan can be used in place of the well assessment to meet the
nonendangerment standard if applied to the UIC wells or documentation must be
provided to show that the well does not pose a threat to groundwater. Examples
of documentation include, but are not limited to, a site drainage map for the
UIC wells or a no-exposure certification form completed for discharges to
ground.
(d) 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 nonendangerment standard by applying the
storm water management programs developed to comply with the federal Water
Pollution Control Act to their UIC wells. For existing UIC wells receiving new
sources of storm water, construction phase and post-construction storm water
controls must be applied to all development and redevelopment projects in
accordance with applicable storm water manuals.
(3) Class V UIC wells not used
for storm water management:
(a)
New UIC wells that are
not used for storm water
management must:
(i) Not directly discharge
into an aquifer, except for wells listed in WAC
173-218-040(5)(a)(ii) through (iv), (vii) through
(xi), (xiii), (xiv) and (xv). A separation
between the bottom of the well and the top of the aquifer is required;
and
(ii) Meet additional
groundwater protection requirements if the UIC well is located in a groundwater
protection area (see WAC
173-218-030 ) as determined by
other state laws or by local ordinances.
(b)
Existing registered UIC
wells that are not used for storm water management are already
considered to be rule authorized. To verify that current site practices are
protective of groundwater quality, the owner or operator must complete a survey
from the department except for UIC wells used at CERCLA sites. The department
will provide written notification that the current site practices are
adequate.
(c)
Existing
UIC wells that are not registered and not used for
storm water management must meet the requirements for new wells.
Statutory Authority: Chapter 80.80 RCW. 08-14-011 (Order
07-11), § 173-218-090, filed 6/19/08, effective 7/20/08. Statutory
Authority:
Chapters
43.21A and
90.48 RCW. 06-02-065 (Order 01-10),
§ 173-218-090, filed 1/3/06, effective 2/3/06. Statutory Authority:
RCW
43.21A.445. 84-06-023 (Order DE 84-02),
§ 173-218-090, filed 2/29/84.