This chapter is applicable to all proposed new or altered domestic
wells in the Town of West Greenwich, whether or not existing prior
to March 10, 2004. Only new overburden or bedrock wells to be used
as a domestic well, as defined herein, which meet the standards of
the Department of Environmental Management and this chapter shall
be permitted.
All terms utilized in this chapter shall be consistent with
the definitions published in the RIDEM Water Well Regulations, promulgated
in December 1989, as may be amended from time to time, and in accordance
with the following:
ALTERING A WELL
The deepening, reaming, casing, re-casing, perforation, re-perforation,
installation of liner pipe, packers, seals, and any other material
change in the design or construction of a well.
DOMESTIC WELL
A well used to serve one or more residences for the purpose
of supplying water for drinking, culinary, or household uses, and
which is not a public water supply as defined by the Rhode Island
Department of Health.
EFFECTIVE STORAGE CAPACITY
The volume of standing water in a well that is available
for removal and use, and is capable of being pumped from the well.
EFFECTIVE WELL DEPTH
The height of the water column in a well that is available
for removal and use (i.e., the distance between the static water level
and the pump level).
RECOVERY
The rise in static water level in a well that occurs when
discharge from that well or a nearby well is stopped.
WELL
Any artificial opening or artificially altered natural opening,
however made, by which groundwater is sought, or through which groundwater
flows under natural pressure, or is artificially withdrawn or injected.
This definition shall not include a natural spring nor test holes
for water table determinations.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. I)]
WELL YIELD
The quantity of water per unit of time which may flow or
be pumped continuously from a well.
Prior to the commencement of drilling activities at the site
of a proposed domestic well, the well owner or the owner's designee
shall provide notice to the Town Building Official of the owner's
intent to install a well. Verbal and/or written notice will be received
by the Town at least 48 hours prior to the commencement of drilling.
If, for any reason, the scheduled date(s) of drilling changes, the
Town will be notified of the new date of drilling at least 48 hours
in advance of such date. All times specified in this section shall
not include weekends and state or federal holidays.
Prior to the commencement of yield testing activities at a newly
installed domestic well, the well owner, or the owner's designee,
will provide notice to the Town Building Official of the date and
exact time of test commencement. Verbal notice shall be received by
the Town at least 48 hours prior to the scheduled date of the yield
test, and at least two hours' notice will be given of the exact start
time of the test. If for any reason the scheduled time or date of
the start of the yield test changes, the Town will be notified immediately.
The well owner will provide notification of the new time and date
in accordance with the notification requirements detailed above. All
times specified in this section shall not include weekends and state
or federal holidays.
A yield test will be performed on all newly installed or altered
domestic wells. The yield test will be conducted in accordance with
all current state requirements and industry standards, as well as
the additional requirements stipulated herein. The duration of the
yield test will be a minimum of five hours, and will demonstrate that
the well is capable of providing a sufficient supply of water for
the proposed use. The yield test will be conducted at a constant flow
rate for the duration of the test. Requirements supplemental to existing
state requirements are discussed below.
A. Accounting
for effective storage capacity of well. To ensure a domestic well
is capable of producing the RIDEM enforceable required well yield,
the removal of the effective storage capacity of the well shall be
incorporated into the yield test. To incorporate the effective storage
capacity of a six-inch-diameter well into the yield test, the formulas
detailed below shall be utilized. If a well owner or installer proposes
to construct a domestic well with a diameter other than six inches
in size, the following formulas shall be revised by the Town's consultant
on a case-by-case basis. A well owner or installer proposing to install
a well with a diameter other than six inches shall submit a written
request to the Town identifying the specific proposed well construction
details. The Town's consultant shall then provide revised formulas
to determine the well installation and testing requirements.
(1) Determine the required RIDEM well yield. The RIDEM required well
yield, as documented in the Water Well Regulations as may be amended
from time to time. For example:
(a)
With a yield of five gallons per minute a minimum well depth
of 100 feet is required.
(b)
With a yield of 3.5 gallons per minute a minimum well depth
of 150 feet is required.
(c)
With a yield of two gallons per minute a minimum well depth
of 200 feet is required.
(d)
With a yield of one gallon per minute a minimum well depth of
300 feet is required.
(e)
With a yield of 0.5 gallon per minute a minimum well depth of
450 feet is required.
*Note: the preceding requirements were developed by RIDEM based
upon a six-inch-diameter well with a static depth to water level of
25 feet to 35 feet below the ground surface.
|
(2) Determine the effective storage capacity.
(Depth to top of pump (feet) - Measured depth to water (feet))
= Effective Well Depth (feet)
|
Effective Well Depth (feet) x 1.5 (gallons/feet)
|
=
|
Effective Storage Capacity (gallons)
|
(3) Determine the required constant pump rate to be pumped from the well
during the yield test:
Effective Storage Capacity (gallons)
Yield Test Duration (hour)* x 60 (minutes)
|
+
|
Required RIDEM Yield (gpm)
|
=
|
Required Constant Pump Rate (gpm)
|
The required constant pump rate shall be pumped from the well
for the duration of the yield test.
|
B. Location
of discharge line. The pump discharge line shall be located so as
to eliminate recirculation of pumped water during the yield test.
The discharge point for water pumped during yield tests shall be located
at least 50 feet away and topographically lower than the production
well.
C. Collection
of depth-to-water measurements.
(1) Depth-to-water measurements, accurate to within 1/10 of one foot,
shall be collected at key points during the yield test. Key points
include immediately prior and subsequent to the start of the yield
test, immediately prior and subsequent to the finish of the yield
test, and at a minimum every one-half hour during the yield test.
(2) Sufficient depth-to-water measurements shall also be collected to demonstrate compliance with the recovery requirement discussed in Subsection
D below.
D. Recovery
requirement.
(1) For wells with an effective well depth of 450 feet or less, the well
owner shall demonstrate that the water level in the well has recovered
to at least 85% of the static water level (water level measured prior
to commencement of the yield test) within 18 hours of the end of the
yield test. To demonstrate compliance with the recovery requirement,
one water level measurement documenting a minimum of 85% recovery
shall be collected no more than 18 hours after to demonstrate compliance
with this requirement:
Effective Well Depth@ <18th hour
Effective Well DepthStatic
|
x 100 > 85
|
(2) For wells with an effective well depth greater than 450 feet, the
well owner shall demonstrate that the well recovers to 85% of the
static water level, as detailed above, or that the well recovers at
a rate of 20 feet per hour for a period of 18 hours. To demonstrate
compliance with the recovery requirement, one water level measurement
collected immediately after the end of the yield test shall be compared
to a water level measurement collected no less than 12 hours and no
more than 18 hours after the end of the yield test. The following
formula shall be used to demonstrate compliance with this requirement:
Effective Well Depth@ # Hour - Effective
Well Depth@ end of yield test
# Hours
|
> 20 feet
|
Note: # Hour = The number of hours between the end of yield
test and the final water level measurement (must be between 12 and
18 to ensure that the average recovery rate of the well is not skewed
by rapid recovery immediately following the completion of the yield
test).
|
The Town's consultant may perform unannounced spot inspections
during the yield test. During inspections, the Town's consultant may
observe the yield testing procedures, discharge location, well location,
well depth, and pumping rate, or any other aspect of the well construction
or testing procedure deemed relevant by the consultant to verify compliance
with RIDEM and Town regulations. The latitude and longitude of the
well may also be recorded through the use of a handheld global positioning
system (GPS) unit, or other acceptable means.
The RIDEM well completion report shall be completed and received
by RIDEM and the Town Building Official within 15 business days of
completion of the yield test. The well completion report shall be
reviewed by the Town's consultant to assess the accuracy, completeness,
and acceptability of the well construction and yield test, and the
ability of the well to provide a sufficient water supply to meet the
intended use of the property. Issuance of a building permit from the
Town Building Official shall be dependent upon submission and approval
of the well completion report by the Town and the Town's consultant.
In addition to the RIDEM well completion report, the well owner
shall complete the Town of West Greenwich well completion form. The
Town well completion form shall be completed and received by the Town
Building Official within 15 business days of completion of the yield
test. The Town well completion form shall be reviewed by the Town's
consultant to assess the accuracy, completeness, and acceptability
of the well construction and yield test. Issuance of a building permit
from the Town Building Official shall be dependent upon submission
and approval of the Town well completion form by the Town and the
Town's consultant.
The Town reserves the right to request additional testing or
assessment of any well if any of the RIDEM or Town requirements have
not been met to the satisfaction of the Town or the Town's consultant.
Incomplete or otherwise deficient well completion reports or questionable
yield testing results or construction details may warrant a request
for additional testing or assessment.
Nothing in this chapter shall preclude the emergency drilling of a drinking water well for a homeowner or tenant on an interim basis in the event a residence loses its water supply. If a well is drilled and installed under this provision, then the homeowner or tenant shall notify the Town Building Official no later than the next business day and will comply with all other provisions of §§
378-4 through
378-12 of this chapter as soon as possible.