[Ord. 262, 9/17/2007]
1.
Water Resources Impact Study. A water resources impact study is required
for:
2.
Purpose. The purpose of the study is to estimate the impact of the
additional water withdrawals on existing nearby wells, underlying
aquifers and streams and to assure the availability of reliable, safe
and adequate water supplies to support the intended land uses within
the capacity of available water resources and to coordinate land use
policies with policies for providing water supply in an environmentally
sound manner that protects the quality and quantity of groundwater.
Any proposed water system or on-lot water supply for any zoning permit,
subdivision and any land development which does not provide an adequate
water supply for use, or which adversely affects nearby wells or streams
shall be cause for denial of the well utilization permit, subdivision
or land development application, unless an alternate water supply
is available.
3.
Supply Requirements. The adequacy of the water supply shall be determined
based on the following assumptions:
A.
Residential. An average of 3.5 persons per dwelling unit, with each
person assumed to use 150 gallons of water per day.
B.
Nonresidential. A professional engineer shall prepare an estimate
of the quantity of water needed for the proposed use. The estimates
shall include peak hourly, peak daily and average daily water demand.
The estimate shall also include water needs for fire flow.
4.
Report Requirements. The water resources impact study shall be prepared
by a licensed professional geologist qualified in hydrogeology and
a professional engineer registered in the Commonwealth of Pennsylvania
and shall include the following:
A.
Calculations of the projected water needs using the criteria set
forth in the following references:
(1)
Public Water Supply Manual, Bureau of Water Supply and Community
Health, Pennsylvania Department of Environmental Protection, Harrisburg,
PA (current edition at the time the report is prepared).
(2)
Guide for Determination of Required Fire Flow by the Insurance
Services Office (ISO) (current edition at the time the report is prepared).
(3)
American Water Works Association (AWWA) standards and manuals
for the American Water Works Association, Denver, CO (current edition
at the time the report is prepared).
B.
A geological map of the area within a 1.0-mile radius of the site.
The map shall be at a minimum scale of one inch equals 2,000 feet
and shall clearly show the location of the proposed site relative
to the entire Township boundary.
C.
The location of all fault lines, lineaments, and fracture traces
within 1/2 mile of the site, regardless of whether the area is within
the municipal boundary of Wrightstown Township.
D.
The locations of all existing and proposed wells within 1/2 mile
of the site, and all large withdrawal wells (over 10,000 gpd) within
one mile of the site.
E.
The location of all existing and proposed on-lot septic systems and
sewer lines within 1/2 mile of the site.
F.
The location of all streams, perennial and intermittent, within 1/2
mile of the site.
G.
Consideration of water impact studies prepared by other developers
in the Township or adjoining Townships determined to be relevant by
the Township.
H.
The text of the study shall contain pertinent data, analysis and
methods used to arrive at the study's conclusions. Appendices shall
contain raw and summary data.
I.
All figures contained within the study shall have complete legends,
titles, and scales.
J.
All numerical parameters within the study shall be presented with
appropriate units, and all data shall be referenced by source, date,
location and time, where appropriate.
K.
Relevant maps shall be supplied with the study identifying the information
set forth above.
L.
A recitation of the aquifer characteristics underlying the site and
their long-term drought recharge capability based on site-specific
investigation or on accepted published data. Long term drought recharge
capability shall be defined as the average amount of water that can
be withdrawn from an aquifer during extended periods of low rainfall
and/or high temperatures without adverse effects on existing wells
and stream flow in the surrounding area.
M.
Based on the drought recharge capability of the underlying aquifer
and the calculated daily groundwater withdrawals of the project, a
hydrologic budget for the subject site property itself and for the
surrounding area within 1/2 mile of the site.
N.
A plan showing the hydrologic environment within which the wells
which are proposed to be utilized are located.
O.
A determination aided by the results of the hydrologic budget, of
whether the potential exists for causing adverse effects on the hydrologic
environment by the proposed use, subdivision or land development.
P.
Measures proposed to mitigate any potentially adverse impacts identified.
Q.
A statement of the qualifications of the person(s) preparing the
study.
5.
Test Wells Required. A water resources impact study shall include
testing of the well(s) for the quantity and quality of the water.
The testing shall follow the procedures in Part 2E and Part 2F of
this Part.
6.
Aquifer Test of Wells.
A.
For each well that is constructed:
(1)
An accurate geologic log should be constructed during the drilling
of the well giving a detailed description of the type and thickness
of rocks encountered. Additionally, the log should contain information
on the depth and thickness of all water bearing zones encountered
and the yield from each zone. Yield from the well must be measured
using a quantitative method.
(2)
A pumping test of not less than 72 hours duration shall be conducted
at a rate of not less than 150% of the intended long-term withdrawal
from the well. This rate must be determined by a step test and approved
by the Township before the start of the pumping test. The seventy-two-hour
test shall be conducted at a constant pumping rate that should not
deviate greater than +/-5% during the test. Notice of all pumping
tests shall be given to the Township at least 72 hours before commencing
the pumping test.
B.
In order to determine the impact of the project well on existing
wells, a representative sample of existing wells, evenly spaced around
the pumping well, shall be monitored for changes in water level. The
number and location of monitoring wells shall be subject to approval
by the Township before conducting a step test. Sufficient well monitoring
shall be performed to allow for the construction of hydrographs showing
a continuous record of well levels before, during and after the pumping
test.
C.
A means of accurately measuring the well discharge shall be provided
subject to approval by the Township.
D.
Well discharge shall be directed away from the site by a method suitable
to the Township and to a point suitable to the Township.
7.
Water Quantity Analysis.
A.
The study shall contain a water quantity analysis which shall include
locations and design of proposed wells and wells serving adjacent
land parcels within a half mile distance from the site boundary.
B.
The study shall contain a current water table contour map (feet above
mean sea level) based on available groundwater and surface water monitoring
points. All proposed developments are required to utilize for this
purpose a minimum of three existing or new groundwater monitoring
points, optimally positioned to allow the determination of groundwater
flow direction. For sites greater than 100 acres, there shall be at
least one monitoring well for each 33 acres, or a fraction thereof,
of the site.
C.
The study shall contain existing geologic and soil maps, updated
with site specific refinements.
D.
The study shall contain the result of a pumping test 72 hours following
equilibrium, but not more than 120 hours, with the following features:
(1)
The test shall be conducted during a period of no significant
recharge event, unless the influence of recharge can be factored out.
(2)
The test shall include one pumping well (roughly centered on-site)
and at least two observation wells, all completed in the same hydrogeologic
unit with their positions established by survey and distributed at
appropriate distances along and across geologic strike from the pumping
well.
(3)
Analyses shall include all pumping and recovery calculations
of hydraulic conductivities (directional), specific yield, and specific
capacity, and long-term sustainable well yield (tabulated).
(4)
The test shall be conducted as set forth in the above referenced
subsections with a pumping rate equal to or greater than the proposed
peak rate of groundwater use.
(5)
One pumping test (done separately and at the same time if there
are two or more separate subdivisions) shall be required for every
30 homes in the proposed subdivision.
E.
The study shall contain a projected piezometric surface contour map
of the proposed pumping scheme, after 60 days without precipitation
recharge. The study shall describe methods, assumptions, and site-specific
hydrogeologic conditions such as anisotropy, boundaries, sloping water
table, and the influence of adjacent withdrawals, that were considered
and used to prepare the piezometric surface contour map.
F.
The study shall include a map illustrating the drawdown effects upon
off-site wells and springs located within 1/2 mile distance from the
site boundary, indicating drawdowns of one foot or more, occurring
during a year with a natural recharge rate of a one year in 10 frequency.
G.
The study shall describe the effects of any proposed on-site disposal
system on groundwater recharge, assuming 20% operational and evaporative
losses.
H.
Where separate wells are proposed for individual lots, the study
shall demonstrate that each well is likely to provide sufficient (equal
to or greater than six gallons per minute) yield.
8.
Water Quality Analysis.
A.
The study shall contain groundwater quality analyses which shall include all of the parameters required by paragraph .F hereof. The groundwater quality analyses shall be conducted on a pumped water sample collected just prior to the completion of a pumping test (See "Water Quantity Analysis," Subsection 7, herein). Groundwater samples shall be required from each hydrogeologic unit from which a withdrawal is proposed and for every required pumping test.
B.
The study shall contain the data from the above analyses, along with
interpolated (for the site) values, range of values, and drinking
water standard values as set forth in the Federal Safe Drinking Water
Act. All laboratory analyses shall be performed by a PA DEP certified
laboratory and shall be included in the appendix to the study.
C.
The study shall contain existing water quality data obtained from
nearby, adjacent groundwater sources including data presented in subsequent
monitoring data collected by Wrightstown Township or from other studies
performed for other developments within the Township or within one
mile of the perimeter of the site.
D.
The study shall indicate the location and design of all on-site sewage
disposal systems.
E.
The study shall describe anticipated water quality impacts to areas
located down-gradient and areas located along geologic strike, assuming
conservatively large wastewater loadings of NO3N at 45 mg/l and low natural groundwater recharge rates equal to
a one year in 10 frequency, or provide an alternative recharge rate
based on documented, updated information.
F.
In addition, the quality of the water produced by the well shall
be tested to determine compliance with the following maximum contaminant
limits by a water quality laboratory certified by the Department of
Environmental Protection of the Commonwealth of Pennsylvania:
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Physical Characteristics:
| ||||
|
(1)
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Turbidity
|
1 ntu
| ||
|
(2)
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Color
|
15 units
| ||
|
(3)
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Threshold Odor Number
|
3 units
| ||
|
(4)
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pH
|
6.5 - 8.5
| ||
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Chemical Characteristics:
| ||||
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(5)
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Chloride
|
250.00 mg/l (ppm)
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(6)
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Nitrate/Nitrite Nitrogen
|
10.00 mg/l (ppm)
| ||
|
(7)
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Iron
|
0.30 mg/l (ppm)
| ||
|
(8)
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Sodium
|
20.00 mg/l (ppm)
| ||
|
(9)
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Manganese
|
0.05 mg/l (ppm)
| ||
|
(10)
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Copper
|
1.00 mg/l (ppm)
| ||
|
(11)
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Hardness
|
250.00 mg/l (ppm)
| ||
|
(12)
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Detergent (MBAS)
|
0.50 mg/l (ppm)
| ||
|
(13)
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Total Dissolved Solids
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500.00 mg/l (ppm)
| ||
|
(14)
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TCE (Trichloroethylene)
|
0.005 mg/l
| ||
|
(15)
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Phenol
|
5.00 mg/l (ppm)
| ||
|
(16)
|
Benzene
|
0.005 mg/l
| ||
|
(17)
|
Toluene
|
1.00 mg/l
| ||
|
(18)
|
Xylenes
|
10 mg/l
| ||
|
(19)
|
Carbon Tetrachloride
|
0.005 mg/l
| ||
|
(20)
|
o-Dichlorobenzene
|
0.6 mg/l
| ||
|
(21)
|
para-Dichlorobenzene
|
0.075 mg/l
| ||
|
(22)
|
1, 2-Dichloroethane
|
0.005 mg/l
| ||
|
(23)
|
1, 1-Dichloroethylene
|
0.007 mg/l
| ||
|
(24)
|
cis-1, 2-Dichloroethylene
|
0.07 mg/l
| ||
|
(25)
|
trans-1, 2-Dichloroethylene
|
0.1 mg/l
| ||
|
(26)
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Dichloromethane
|
0.005 mg/l
| ||
|
(27)
|
1, 2-Dicloropropoane
|
0.005 mg/l
| ||
|
(28)
|
Ethylbenzene
|
0.7 mg/l
| ||
|
(29)
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Monochlorobenzene
|
0.1 mg/l
| ||
|
(30)
|
Styrene
|
0.1 mg/l
| ||
|
(31)
|
Tetrachloroethylene
|
0.005 mg/l
| ||
|
(32)
|
1, 2, 4-Trichlorobenzene
|
0.07 mg/l
| ||
|
(33)
|
1, 1, 1-Trichloroethane
|
0.2 mg/l
| ||
|
(34)
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1, 1, 2-Trichloroethane
|
0.005 mg/l
| ||
|
(35)
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Vinyl Chloride
|
0.002 mg/l
| ||
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(36)
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Sulphate
|
250 mg/l
| ||
|
(37)
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Lead
|
0.015 mg/l
| ||
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Bacteriological Characteristics:
| ||||
|
(39)
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Total Plate Count
|
Less than 500 counts per ml.
| ||
|
(40)
|
Total Coliform
|
0 cfu/100 ml
| ||
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mg/l = milligrams per liter
| |
|
Cfu = colony forming units
| |
|
ml = milliliters
| |
|
pH units are = -Log [H+]
| |
|
ppm = mg/l
| |
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ntu = nephelolometric turbidity units
|
G.
The study shall describe the methodology applied to define on-site
and off-site groundwater quality impacts.
9.
Test Report. A report shall be prepared and submitted to the Code Official and shall accompany the submission of the test well results and observation data. The report shall contain the information required in § 26-242, Subsection 1C. The report shall analyze and interpret all of the data as to the impact on the groundwater supply and existing wells. Conclusions shall be drawn from the analysis as to the appropriateness of the site for the proposed water supply system; probable effects of long-term pumping on well levels within one mile of the test well; and compliance with the water quantity and water quality Subsections 7 and 8 of this section. The credentials of the individual(s) preparing the report shall be included. Reports shall be signed and sealed by the licensed professional engineer and licensed professional geologist responsible for the work.
If the results of the pumping test indicate a potential for
adverse effects on neighboring wells, the applicant shall provide
security in accordance with Part 2G hereof assuring recompense to
the owners of any neighboring wells adversely affected.
10.
If the results of the pumping test indicate a potential for adverse
effects on neighboring wells as determined by the Township Engineer,
the applicant shall conduct pre-construction monitoring of any wells
likely to be impacted, provided that the owner of such well provides
appropriate written authorization to the applicant so as to permit
applicant to enter upon the owner's property for such pre-construction
monitoring.
11.
Application Submission. The complete submission to the Township shall
include any and all applications, reports, or supplemental information
submitted to the BCHD, the PA DEP and/or the DRBC, as required by
those agencies.
12.
Preliminary Plan. All well testing requirements as set forth herein
for a proposed well shall be met by the applicant for a subdivision
or land development prior to seeking preliminary plan approval from
the Board of Supervisors.
