Current through Register Vol. 24-18, September 15, 2024
(1)
Groundwater sources submitted to the department or health officer for design
approval under WAC
246-291-120 must comply with the
following requirements:
(a) Drinking water
shall be obtained from the highest quality source feasible.
(b) All permanent groundwater sources must:
(i) Be designed to be physically connected to
the distribution system;
(ii) Be a
drilled well constructed in accordance with chapter 173-160 WAC; and
(iii) Meet water quality requirements under
WAC 246-291-170.
(c) The department or health officer shall
not approve a design for a new or expanding Group B system using a GWI
source.
(d) The department or
health officer shall not approve a design for a new or expanding Group B system
using a potential GWI source until a hydrogeologic evaluation is completed by a
licensed hydrogeologist or engineer that determines the source is not GWI. The
GWI evaluation and determination must be completed before the department or
health officer will review the Group B design report.
(2) Before pursuing groundwater source
approval under this section, a purveyor shall contact the department or local
health jurisdiction to identify any additional requirements.
(3) A purveyor shall provide a copy of the
following to the department or health officer to obtain groundwater source
approval:
(a) The water right permit, if
required, for the source, quantity, type, and place of use;
(b) The water well report, as required under
WAC 173-160-141;
(c) The well site inspection report form
completed by the department or local health jurisdiction, or
designee;
(d) A map showing:
(i) The project location;
(ii) A six hundred foot radius around the
well site designating the preliminary short-term groundwater contribution area;
and
(iii) The perimeter of a one
hundred foot SCA, meeting the requirements in subsection (5) of this
section.
(e) A map
showing topography, distances to the well from existing property lines,
buildings, potential sources of contamination within the six hundred foot
radius around the well, and any other natural or man-made features that could
affect the quality or quantity of water;
(f) The recorded legal documents for the
SCA;
(g) Results from an initial
analysis of raw source water quality from a certified lab, including, at a
minimum:
(i) Coliform bacteria;
(ii) Inorganic chemical and physical
parameters under WAC
246-291-170, Tables 2, 3, and 4;
and
(iii) Other contaminants, as
directed by the department or health officer in areas where it determines that
other contamination may be present.
(h) Pump test data establishing groundwater
source capacity including, but not limited to:
(i) Static water level;
(ii) Sustainable yield;
(iii) Drawdown;
(iv) Recovery rate; and
(v) Duration of pumping.
(i) Additional pump testing in locations
where water resource limitations or known seasonal groundwater fluctuations may
affect future reliability as directed by the department or health
officer.
(4) Groundwater
source capacity.
(a) A groundwater source for
a Group B system with residential connections must be pump tested to determine
if the well(s) and aquifer are capable of reliably supplying water that meets
the minimum requirements under Table 1 of this section.
(b) A groundwater source must be pump tested
to determine if the well(s) and aquifer are capable of supplying water at the
rate required to provide the water volume as determined under WAC
246-291-200 for a source
supplying a Group B system with:
(i)
Nonresidential service connections; or
(ii) Both residential and nonresidential
service connections.
(c)
Where a locally adopted watershed plan or ecology watershed rule under Title
173 WAC establishes a higher water supply requirement, the purveyor shall use
the higher value to assess the adequacy of the source of supply.
(d) A purveyor shall design the Group B
system to meet the requirements under Table 1, even if a locally adopted
watershed plan or watershed rule under Title 173 WAC limits water use below the
values in Table 1.
Table 1 Minimum Source Capacity and Water Supply for
Residential Service Connections
|
County
|
Gallons per day per dwelling
unit
|
|
Clallam, Clark, Cowlitz, Grays Harbor, Island,
Jefferson, King, Kitsap, Lewis, Mason, Pacific, Pierce, San Juan, Skamania,
Skagit, Snohomish, Thurston, Wahkiakum, and Whatcom
|
750
|
|
Adams, Asotin, Benton, Chelan, Columbia, Douglas,
Ferry, Franklin, Garfield, Grant, Kittitas, Klickitat, Lincoln, Okanogan, Pend
Oreille, Spokane, Stevens, Walla Walla, Whitman, and Yakima
|
1,250
|
(5) SCA.
(a) A purveyor shall establish the SCA around
each groundwater source to protect it from contamination.
(b) The SCA must have a minimum radius of one
hundred feet, unless technical justification submitted by a licensed
hydrogeologist or engineer to the department or health officer supports a
smaller area. The justification must address geological and hydrogeological
data, well construction details, and other relevant factors necessary to
provide adequate sanitary control.
(c) The department or health officer may
require a larger SCA if geological and hydrological data support such a
decision.
(d) A purveyor shall own
the SCA, or the purveyor shall have the right to exercise complete sanitary
control of the land through other legal provisions.
(e) A purveyor shall record a restrictive
covenant to the title of each property that is sited partially or completely
within the SCA to protect the SCA in perpetuity.
Statutory Authority: RCW 43.20.050 and chapter 70.119A RCW.
12-24-070, § 246-291-125, filed 12/4/12, effective
1/1/14.
