In accordance with MGL c. 111, § 31, as amended, in
regards to wells in the Town of Plainville.
As used in this chapter, the following terms shall have the
meanings indicated:
ABANDONED WATER WELL
A well that has not been used for water supply for a period
of one year or more, unless the owner declares his intention to use
the well again for supplying water within one year of the time use
ceased.
AQUIFER
A water-bearing geological formation (consolidated or unconsolidated)
that transmits water in sufficient quantities to supply a well.
CASING
An impervious durable pipe placed in a hole to prevent the
walls from caving in, and to seal off surface draining or undesirable
water, gas, or other fluids and prevent their entering the well. Specific
types include:
A.
TEMPORARY CASINGA temporary casing placed in soft, sandy, or caving surface formation to prevent the hole from caving in during drilling.
COMMISSION
The Water Resources Commission established under Chapter
620 of Acts of 1956.
DRAWDOWN
The measured distance between the static water level and
the pumping water level.
DWELLING UNIT
The room or group of rooms within a dwelling used or intended
for use by one family or household for living, sleeping, cooking and
eating. Dwelling unit shall also mean a condominium unit.
REGULATING AGENCY
The local Board of Health or its designee which shall administer
regulations pertaining to water well construction.
STATIC WATER LEVEL
The distance measured from established ground surface to
the water surface in a well not being pumped, influenced by pumping
nearby, or flowing under artesian pressure.
WELL DRILLER
Any person, association, partnership, company, corporation,
or trust that constructs a water well licensed by the Water Resource
Commission.
WELL OR WATER WELL
Any hole or shaft constructed into the ground for the purpose
of extracting or injecting water. This definition shall not include
wells to dewater excavations or stabilize hillside or earth embankments.
It shall include wells connected to heat pumps.
A.
HEAT PUMP WELLConsists of a source well and a discharge well which could be one in the same, provided that it is a closed loop system where nothing is added to or taken from the water except heat and no air is in contact with the return water. A heat pump delivers water by way of the source well from an aquifer through a heat exchanger and returns it to the aquifer via the discharge well. The system utilizes the thermal energy stored in groundwater for space heating or cooling.
B.
DOMESTIC WELLA well used for domestic water supply with one service connection and/or serving less than 25 people. This shall include residential lawn and garden irrigation wells.
D.
LOCAL WATER SUPPLYA well which supplies drinking water for two to 14 service connections which serve less than 25 people.
These standards shall apply to all types of wells described in §
784-3. Before a change in existing well use is made, the new use shall comply with requirements specified herein.
No person shall engage in the business of constructing wells
within the commonwealth unless he is registered with the Water Resources
Commission, Division of Water Resources, as required by the Water
Well Drillers Registration Act (MGL c. 21, § 16).
The annular space between the protective well casing and the
wall of the drilled hole or the surface casing shall be effectively
sealed to protect against contamination or pollution by surface and/or
shallow subsurface waters. This shall be accomplished in accordance
with guidelines set forth below.
A. Depth of seal.
(1) The following is the minimum depth of seal below ground surface for
various uses of wells:
Type
|
Depth of Surface Seal
(feet)
|
---|
Local water supply wells
|
20
|
Domestic wells
|
4
|
(2) Exceptions are shallow wells where the water to be developed is a
depth of less than 20 feet. In this instance, the depth of seal may
be reduced, and special precautions shall be taken in locating the
well with respect to possible sources of contaminations.
(3) The annular space shall be sealed to a minimum depth of 20 feet from the surface of the ground when the well is close to individual domestic wells or to sources of contamination or pollution as described in §
784-8.
(4) Local conditions, such as the existence of shallow subsurface waters
of undesirable quality, may warrant consideration of sealing the annular
space around the agricultural wells.
B. Sealing conditions. The following are requirements for sealing the
protective casing of a well:
(1) Wells that penetrate unconsolidated material.
(a)
Driven wells or well construction by cable tool method. The temporary surface or protective casings may function as the seal, provided the length of casing corresponds to the depth of seal specified in Subsection
A of this section.
(b)
Rotary, auger or jetted well construction. The annular space between the hole or surface or temporary casings or the protective casing shall be filled with sealing material to the depth specified in Subsection
A of this section.
(2) Wells that penetrate impervious formations. If a consolidated formation or an impervious unconsolidated formation is encountered within five feet of the specified depth of seal described in Subsection
A of this section, the seal should be extended at least five feet into the impervious formation.
(3) Gravel-packed wells. The gravel pack of gravel-packed wells shall
terminate at the base of the protective seal.
(4) Wells penetrating consolidated rock. A hole of sufficient diameter
to accommodate protective casing must be constructed and the annular
space between rock and casing sealed to the depth specified in this
section.
C. Sealing material. The sealing material shall consist of neat cement,
cement grout, puddles clay, or concrete. Organic polymer muds shall
not be allowed.
(1) The neat cement mixture shall be composed of one bag of portland
cement (94 pounds to five to seven gallons of clean water).
(2) Quick-setting cement, retardants to setting, and other additives
including hydrated lime to make the mix more fluid (up to 10% of the
volume of the cement) and bentonite (up to 5%) to make the mix more
fluid and reduce shrinkage may be used.
(3) Clay in the form of a mud-laden fluid is similar to and has the advantages
of neat cement and cement grout. This is a disadvantage in that clay
may separate out from the fluid.
(4) A bentonite-gelatinous mud is recommended. Concrete is useful in
sealing large diameter wells, particularly where the width of annular
ring is several inches or more. However, unless care is exercised
during the placement, the coarse aggregate may become separated from
the cement.
D. Thickness of seal. The thickness of the seal shall be at least one
inch, and not less than three times the size of the largest coarse
aggregate used in the sealing material.
E. Placement of seal. The sealing material shall be installed in one
continuous operation from the bottom of the interval to be sealed
to the top.
F. Sealing casing into bedrock. For all wells which terminate in bedrock,
a permanent casing shall extend from 18 inches above the ground or
floor of a pit into bedrock a minimum of 10 feet below the bedrock
surface.
A well installed in an unconsolidated sand and gravel aquifer
commonly has a well screen. Screen openings shall be properly sized
based on sieve analysis of material at the screen depth. The well
shall be properly developed to produce sand-free water at the pumping
rate of the permanent pump.
Where a well penetrates aquifers separated by confining layers
and any of the aquifers contain water that would be a contaminant,
contaminated strata shall be sealed to prevent entrance of the water
into the well, or its migration to other aquifer(s).
A. The contaminated stratum shall be sealed by placing impermeable material
in the annular space between the protective casing and the contaminated
stratum.
(1) The seal shall extend into upper and lower confining formations for
a sufficient vertical distance to prevent the vertical movement of
water from the producing formation.
(2) Sufficient sealing material shall be installed to fill the annular
space between the casing and the wall in the drilled hole along the
sealed interval and to fill the voids which might absorb sealing material.
Sealing material shall be placed from the bottom to the top of the
sealed interval.
B. Sealing material shall consist of neat cement, cement grout, or other suitable impermeable material. See §
784-10.
All well development and rehabilitation shall be done with care
and by methods that will not cause damage to the well, degrade groundwater
quality, or alter subsurface conditions to allow vertical movement
of contaminated water between aquifers. Hydrofracking of any well
will not be considered unless the current well is a minimum of 600
feet deep, and will require a variance from the Board of Health. The
use of explosives for well development shall be prohibited.
Chemical, physical, and bacteriological analysis of the water,
conducted by a Massachusetts certified laboratory, shall be required.
Water which does not meet the accepted standards of agencies of the
state or federal government for potable water supplies shall be grounds
for the rejection of the well. The well shall be sampled as follows:
A. Prior to approval for issuance of a building permit, a sample shall
be collected.
B. Prior to occupancy of the facility that the well is to serve or any
use of the well water, a sample shall be collected from the building
by a representative of the testing laboratory or an independent service,
maintaining a chain of custody.
C. The samples shall be tested for the following parameters.
(1) A bacteriological test to indicate a zero per 100 ml coliform density.
A total bacteria count (standard plate count) shall also be determined
at 35° C. and shall not exceed 100 bacteria per ml.
(2) Chemical and physical analyses shall be performed for at least the
following:
(a)
Volatile organics (EPA 524) or approved equivalent.
(b)
pH, color, odor, turbidity, iron, manganese, ammonia nitrogen,
nitrite nitrogen, nitrate nitrogen, alkalinity, total hardness, sodium,
chloride, arsenic, and lead.
D. The Board of Health may require other parameters to be tested when,
in its opinion, circumstances particular to the subject location warrant
it.
E. Concentrations shall not exceed the United States EPA Recommended
Maximum Contaminant Levels for Primary and Secondary Drinking Water
Regulations in effect at the time of testing. If the concentration
of sodium is greater than 20 milligrams per liter, or if the nitrate
nitrogen concentration is greater than five milligrams per liter,
or if a volatile organic is detected in any concentration, a document
shall be recorded in the Norfolk County Registry of Deeds, which identifies
the chemicals, their concentrations, and their health effects. A whole
house treatment system for removal of volatile organics shall be installed
if they are detected. A statement shall be included in the recorded
documents to the effect that the treatment unit requires regular maintenance.
If volatile organics are detected in a water sample and then found
to be absent in a subsequent sampling, the requirements for a recorded
document and treatment unit shall only be removed following two successive
samplings which show the absence of such contamination. When treatment
units are installed, sampling and analysis must be performed and submitted
to the Board of Health to demonstrate that the treatment is effective.
Permanent disinfection of a polluted water supply is prohibited.
If the natural water quality does not meet the physical and chemical
criteria as specified, water conditioning shall be required. Water
softener or other treatment backwash shall not be discharged into
the on-site sewage disposal system. Treatment units shall be installed
with the capability of bypassing such units if necessary or desired.
When treatment units are installed, sampling and analysis must be
performed and submitted to the Board of Health to demonstrate that
the treatment is effective.
Pressure tanks for individual home installation shall be diaphragm
type and have an actual minimum liquid capacity of 32 gallons.
A well shall be plumb to allow proper installation and pump
operation.
Special provisions for large diameter (ten-inch or larger in
diameter) shallow wells:
A. Bored wells. All bored wells shall be cased with concrete pipe or steel casing, with joints which are watertight from six inches above surface to the depths specified in §
784-10. The minimum thickness of the surrounding concrete seal shall be three inches.
(1) Steel used in the manufacture of casing for bored wells should conform to the specifications for casing material described in §
784-9A(2). Schedule 40 steel casing for dug wells shall be one-fourth-inch U.S. standard gauge (or plate thickness) for wells of diameters 18 inches to 48 inches.
(2) Precast concrete pipe is usually composed of concrete rings from
one to six feet in diameter and approximately three to eight feet
long. To serve satisfactorily as casing, these rings should be free
of any blemish that would impair their strength or serviceability.
In the portion of the well that is to be sealed the joints shall be
made watertight.
B. Covers. All bored wells shall be provided with a structurally sound
cover to prevent injury to people and to prevent the entrance of undesirable
water or foreign matter and shall be watertight.
Water used for cooling parts of engines, air compressors, or
other equipment, or water used for air conditioning, shall not be
returned to any part of a potable water system or potable aquifer.
All deepening or repair of wells shall meet all the requirements
included in these regulations and shall be done with a permit.
Installation of a water storage reservoir, but not an approved
water pressure tank, requires approval of the Board or its agent.
An owner or occupant using a polluted water supply or a supply
that represents a health hazard shall be notified of the health hazard,
in writing, by the Board or its agent.
See Chapter
759, Variances, of the Code of the Town of Plainville.