4725.4850 WATER-SUPPLY WELL PITLESS ADAPTER OR PITLESS UNIT,
AND WELDED OR THREADED FITTING.
Subpart 1. Pitless adapter or pitless unit. Except as provided in subpart 2, a
connection to a casing of a water-supply well made less than 12 inches above the
established ground surface must be made with a pitless adapter or pitless unit. The
connection must not be submerged in water at the time of installation. Native
materials must be packed tightly around the pitless adapter or pitless unit to the
ground surface. The pitless adapter or pitless unit must:
A. be constructed to provide complete clearance within the internal diameter of
the casing;
B. be designed to be field-welded by holding the welding rod in a vertical or
horizontal position, or bench-welded before field installation with a material as
corrosion-resistant as the parent material;
C. have all threaded joints watertight with no threads exposed;
D. impart no taste, odor, or toxic material to the water; and
E. connect to the casing by a threaded connection, welded connection, bolted
flange with gasket, clamp and gasket, or compression gasket.
A welded, solvent welded, or threaded coupling, adapter, or swaged fitting
meeting the material standards of part 4725.2350, 4725.2550, or 4725.6650, may
be used to connect a casing to a pitless adapter or unit.
Additionally, a pitless unit using a compression seal must provide for the well
casing to extend at least 2.5 inches into the throat of the pitless unit. The
compression collar must be held in place with corrosion-resistant bolts, nuts, and
washers. The installer of a clamp-on or weld-on pitless adapter must use a guide
or template for cutting the hole in the casing to accommodate the pitless adapter.
Pitless adapters and units are fittings attached to or replacing the casing, usually below the frost line, that
allow a water discharge line to exit the casing below frost and not freeze, allow the pump to be removed
without excavation, and allow the casing to be extended above grade for proper venting, service, and
sanitary protection. A pitless adapter is a fitting inserted into a hole in the side of the casing. A pitless unit
is a fitting and upper casing that replaces the casing from the frost line to above the surface. Pitless
adapters and units are so named because they replace the old, unsafe, and unsanitary practice of putting
wells in pits.
Water discharge connections to a water-supply well casing made lower than 12 inches above-grade (even
if the connection is above-ground) must be made with an approved pitless. A connection for venting or
remediation (remedial well), water level measurement, treatment, or electrical may be made with a fitting
as described in subpart 2 below.
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Water-supply well connections made higher than 12 inches above-grade must be made with a threaded
connection, welded connection, rubber expansion sealer, or a bolted flange as detailed in Minnesota
Rules, part 4725.3150. The top of the casing must be covered with a well cap, cover, or pump base as
detailed in Minnesota Rules, part 4725.4950.
The casing extension, from the pitless adapter above-ground, must be made of material which meets the
casing standards as detailed in Minnesota Rules, parts 4725.2250 through 4725.2550. The casing
extension for factory-made pitless units including the spool, adapter, discharge and upper casing
extension may be of materials not meeting the casing standards of Minnesota Rules, parts 4725.2250
through 4725.2550 if the entire unit has been approved by the MDH as an engineered unit.
The water may be pumped down so that the connection is not submerged in water during installation.
This requires a “clear-way”-type pitless. The clear-way requirement applies to all casing sizes, and to
open hole wells as well as screened wells. “Clear-way” means that when the pull pipe, internal drop pipe
fitting assembly, actuator, discharge elbow, spool, drop pipe, and pump are removed; no portion of the
pitless extends inside the inner wall of the casing. This allows for removal or installation of a full-sized
screen or pump, and allows full casing access for rehabilitation or repair.
A pitless unit must be at least as large as the casing, and may be larger. A 4-inch pitless may not be placed
on a 6-inch casing. However, a 6-inch pitless may be placed on a 4-inch casing.
The rules require that no casing threads be exposed on threaded pitless units. Many of the pitless units
currently available have threads exposed when the pitless is threaded onto the casing and upper casing
extension. The use of pitless units with “buried” threads is encouraged. However, the department will
allow pitless units with exposed threads to be used if the units otherwise meet the standards of these rules
and if all exposed threads are corrosion protected by use of a protective coating. The protective coating
must be designed to provide corrosion protection for buried steel, and does not include tape or other
wrapping products.
It is recommended that all water contact components meet ANSI/NSF Standard 61.
This allows pitless units (or adapters) which are threaded onto the casing, welded to the casing, bolted
with a gasket, clamped with a gasket (“clamp-on” type), or compression fittings (“Dresser” type or
“Kwick-connect” type).
The guide is required for holes cut with a torch, reciprocating saw, or method other than a hole saw. The
guide must be followed to cut the correct size hole. Slag, burrs, or rough edges on surfaces which contact
a gasket or “O”-ring must be smoothed. The correct size hole saw must be used in order to prevent leaks.
A leak at the pitless is a common cause of bacterial contamination of the well. Leaks may occur from a
cross threaded casing or discharge line; undertightened, over-tightened, or broken clamp; irregular shaped
hole; missing or defective gasket; separation due to frost; and damage from vehicles.
A list of pitless adapters and units which currently meet the standards is included in the appendix. The list
only includes approved models commonly available, and does not include models out of production
which still may be in stock. Models not on the list may be used if they meet the requirements in these
rules. The MDH may be contacted to review additional models.
332
Subp. 2. Welded or threaded fitting. A welded or threaded fitting meeting the
requirements of part 4725.3150, subpart 2, may be connected to the side, cap, or
cover, of a water-supply well casing and be used for venting, remediation,
measurement of water levels or testing, treatment, or for an electrical connection.
A water discharge line must be connected with a pitless unit or pitless adapter.
STAT AUTH: MS s 103I.101; 103I.111; 103I.205; 103I.221; 103I.301; 103I.401;
103I.451; 103I.501; 103I.525; 103I.531; 103I.535; 103I.541; 103I.621;
HIST: 33 SR 211
4725.4900 [Repealed, 17 SR 2773]
4725.4950 [Repealed 33 SR 211]
4725.5000 [Repealed, 17 SR 2773]
4725.5050 PRIMING WATER-SUPPLY WELL PUMPS.
A pump that requires priming for ordinary use must not be installed on a watersupply well unless the well is only used for a water irrigation system. An irrigation
well pump must be primed only with water free of contamination and carrying a
measurable chlorine residual. An irrigation well equipped with a centrifugal pump
may be primed without chlorination when the pump is filled with water taken
directly from the well.
This does not prohibit the use of a jet or centrifugal pump, or prelube lines on turbines. It is intended to
prohibit pumping equipment that requires opening of the well and introduction of water for each use. This
requirement prohibits ordinary pitcher pumps.
STAT AUTH: MS s 103I.101; 103I.221; 103I.301; 103I.621; 144.05; 144.12;
144.383; 157.04; 157.08; 157.09; 157.13
HIST: 17 SR 2773
4725.5100 [Repealed, 17 SR 2773]
4725.5150 WATER-SUPPLY WELL SUCTION LINE.
Subpart 1. Construction. As specified in part 4715.0510, a suction line for a
water-supply well must be constructed of:
Jet pumps operate by creating a partial vacuum, “drawing” water into the pump. When a jet pump is not
located over the well, a single suction line (in the case of a shallow well jet pump), or a suction line and a
pressure line (in the case of a two pipe or a deep well jet pump) connect the well with the pump. If the
pipe is above ground (and not flooded) and a leak occurs, the pump will break suction and not work. If the
line is buried, and a hole or other leak occurs, contaminants and near-surface water may be drawn into the
333
system, particularly if the soil is saturated. A suction line may only be buried if it is installed within an
outer, concentric pipe with the annular space between the pipes filled with water from the system and
maintained at system pressure (concentric piping). A diagram follows subpart 3.
Part 4715.0510 refers to the Minnesota Plumbing Code, water service pipe standards. The material
standards from the Minnesota Plumbing Code are summarized after each material type.
A. copper;
The Minnesota Plumbing Code requires seamless-tube, Type K soft-temper or Type L soft-temper copper
meeting ANSI Standard H23.1 or ASTM Standard B88 with brass or bronze flare fittings or cast bronze
and wrought solder joint pressure fittings.
B. galvanized iron or steel;
The Minnesota Plumbing Code requires steel pipe to be Schedule 40 or above and meet ANSI Standard
B36.1 or B36.20, or ASTM Standard A53, and wrought iron pipe must be Schedule 40 and above and
meet ANSI B36.2. Fittings must be malleable fittings 150 pounds per square inch and above meeting
ANSI Standard B16.3 or ASTM Standard A197, or steel unions meeting FS Standard WW-V-531 C. All
exposed threads must be coal tar enamel coated and wrapped.
C. cast iron;
The Minnesota Plumbing Code requires cast iron-mechanical (gland type) pipe meeting ANSI Standards
A21.11, A21.2, A21.4, A21.6, or A21.8 with water-service fittings meeting ANSI A21.10; and with
bends, tees, and plugs anchored by rods; and thrust blocks or anchor rods behind all changes of direction
of 45 degrees or greater.
D. plastic pipe.
The Minnesota Plumbing Code requires plastic pipe to be at least 150 pounds per square inch minimum
working pressure for municipal water service and 100 pounds per square inch for other service. The
materials allowed include: polyethylene meeting ASTM Standard D2239 or D2737, or ANSI Standard
B72.1; ABS pipe meeting ASTM Standard D2282, or ANSI Standard B72.3; PVC pipe meeting ASTM
Standard D2241 or D1785, or ANSI B72.2; and polybutylene meeting ASTM Standard D2662 or D2666.
For well water irrigation systems, aluminum pipe may also be used.
Subp. 2. Extensions. A suction line extending outside the well casing must be
protected by being:
A. fully exposed in a building as specified in part 4725.2175;
BUILDING REQUIREMENTS
●
●
●
The building must be constructed at or above the established ground surface.
If a floor drain is installed, it must discharge to the established ground surface, a gravel pocket, or a
sewer constructed to prevent backup of sewage within 50 feet of the well.
Materials or chemicals that may cause contamination of the well or groundwater, including fertilizers,
pesticides, petroleum products, paints, and cleaning solvents, must not be stored in the building.
334
●
●
●
●
Any door must be hinged to swing outward.
There must be a durable watertight concrete floor.
The building must be constructed exclusively to contain and protect the well, pump, water treatment
equipment and water treatment chemicals. No other uses of the building are permitted.
The building must not be contained in, or part of, another building, except that a well house may be
constructed with not more than one wall in common with another building. The common wall must
not allow access to, or be open to, the well house.
B. fully exposed above the established ground surface; or
C. installed within an outer, concentric pipe with the annular space between the
pipes filled with water from the system and maintained at system pressure.
Concentric piping is simply placing one pipe inside another, (see Figure 27). The inner (suction) pipe is
protected by the outer (pressure) pipe. If a hole develops, surface water or soil will not be drawn into the
water stem. On a shallow well system, the space between the pipes is filled with water at system pressure,
but is not circulated. On a deep well suction system, the water between the pipes is circulated down the
well to the jet or venturi as the “drive” water. Concentric piping is the only legal option for a buried
suction line. Connecting concentric pipe requires a special concentric pitless, special fittings such as
concentric seal crosses or ball elbows, and accurate cutting and careful assembly of pipes.
Subp. 3. Exception. An unprotected suction line may be installed below the
established ground surface for an irrigation well if the well is:
A. located in an agricultural field;
B. installed in an unconfined aquifer in unconsolidated material; and
C. used for a manifold collection system under negative pressure.
STAT AUTH: MS s 103I.101; 103I.221; 103I.301; 103I.621; 144.05; 144.12;
144.383; 157.04; 157.08; 157.09; 157.13
HIST: 17 SR 2773; 33 SR 211
335
336
4725.5200 [Repealed, 17 SR 2773]
4725.5250 WATER-SUPPLY WELL PUMP DISCHARGE LINES.
A buried discharge line between a water-supply well casing and the pressure
tank in an installation, including a deep well turbine or a submersible pump, must
not be under negative pressure at any time. If a check valve is installed in a buried
water line between the well casing and the pressure tank, the water line between
the well casing and the check valve must meet the requirements of part 4725.5150
unless equipped with a vacuum release or combination air release and vacuum
release device located between the check valve and the well. Pump discharge lines
must be constructed of materials approved in part 4725.5150, subpart 1.
Minnesota Rules, part 4725.5150 refers to suction lines, and contains the requirement for concentric
plumbing. If a check valve is installed in the buried portion of the water discharge line, the piping must be
concentric, unless a vacuum-release valve is installed. A vacuum-release valve may also be referred to as
a vacuum air-release or vacuum-relief valve for water service. Devices such as the Watts N36 or
equivalent provide vacuum protection but do not discharge trapped air. Devices such as the Val Matic
model 100 through 116 provide protection from a vacuum and exhaust trapped air.
Minnesota Rules, Chapter 4725 require that pump discharge line materials be copper, galvanized iron or
steel, cast iron, or plastic pipe meeting the standards of the Minnesota Plumbing Code, part 4715.0510,
for water service pipe (water line between well and pressure tank). The requirements of the Minnesota
Plumbing Code, part 4715.0510 are summarized above in Minnesota Rules, part 4725.5150, and are not
found in the appendix.
The drop pipe or turbine column in a well is not considered part of the pump discharge line for purposes
of these rules. The rules do not contain material standards for drop pipe or column.
MINNESOTA PLUMBING CODE WATER-SERVICE LINE REQUIREMENTS
In addition to the material standards for pump discharge lines (water service pipe) which reference the
material standards of the Minnesota Plumbing Code, potable water service lines must meet the
installation standards of the Minnesota Plumbing Code, part 4715.1710.
The Minnesota Plumbing Code requirements of part 4715.1710 are summarized below. The rule part is
not reproduced in the appendix.
The Minnesota Plumbing Code requires a 10-foot separation between a water-service line and a
building drain or sewer. If a 10-foot separation cannot be maintained, the administrative authority (local
government enforcing the Minnesota Plumbing Code) may allow the water and sewer line in the same
trench, less than 10 feet apart, if the bottom of the water line is at least 12 inches higher than the sewer,
and if the water pipe is placed on a shelf on one side of the trench. Both the sewer and water pipes must
be air tested. Where the 10-foot separation cannot be maintained and the 12-inch vertical separation and
location on the shelf cannot be maintained, the administrative authority may allow a closer separation if
the sewer pipe is approved plastic or cast iron and the water pipe is copper, cast iron, or plastic and both
are air tested. Where the water line must cross the sewer line, the water line must be at least 12 inches
higher than the sewer within 10 feet of the crossing. Where this is not feasible, the sewer must be of
approved materials from at least 10 feet on either side of the crossing.
337
The Minnesota Plumbing Code requires a water service line to be a minimum of 10 feet from a cesspool,
septic tank, septic tank drainage field, seepage pit, soil treatment system, buried tank containing
petroleum or chemicals, or any other source of pollution.
STAT AUTH: MS s 103I.101; 103I.111; 103I.205; 103I.221; 103I.301; 103I.401;
103I.451; 103I.501; 103I.525; 103I.531; 103I.535; 103I.541; 103I.621; 144.05;
144.12; 144.383; 157.04; 157.08; 157.09; 157.13
HIST: 17 SR 2773; 33 SR 211
4725.5300 [Repealed, 17 SR 2773]
4725.5350 PRESSURE TANKS FOR WATER-SUPPLY WELLS.
Subpart 1. Venting. A pressure relief or air release valve on a pressure tank that
contains subterranean gas and is located in a building must be vented to the
outside.
The venting requirement is intended to prevent the build-up of potentially toxic or explosive gasses
(i.e., methane or hydrogen sulfide) in confined spaces (i.e., basements or well rooms) where pressure
tanks are located. This applies primarily to hydropneumatic-pressure tanks without a bladder or other airwater separation (galvanized tanks).
Minnesota Rules, Chapter 4725 do not require a pressure release valve on a pressure tank, but one is
recommended. In some circumstances, high-pressure submersible pumps can produce sufficient pressures
to rupture (explode) a pressure tank. Typical submersible pumps are set with a 40 psi cut-in and 60 psi
cut-out. A 75 or 80 psi release valve offers protection to pressure tanks that commonly have maximum
(new) working pressure ratings of 90 to 125 psi.
Subp. 2. Buried tanks. A buried or partially buried pressure tank installed on a
water-supply well must:
A. be identified with the manufacturer's name, a serial number, the allowable
working pressure, and the year fabricated;
B. have an interior coating that complies with ANSI/NSF Standard 61-2003e if
the tank has an interior coating in contact with water;
An interior tank coating is not required. However, if the tank has a coating, the coating must meet
ANSI/NSF Standard 61. NSF publishes a quarterly booklet of listed products, their website contains a list,
and products are marked with the NSF logo.
C. have a minimum one-fourth inch wall thickness for a steel pitless adapter
tank attached directly to the well casing;
D. have all connections to the pressure tank welded or threaded; and
E. be installed above the water table.
A list of approved, buried pressure tanks is contained in the appendix.
A pressure tank with a galvanized interior coating or other component which exceeds 8 percent lead may
not be used.
338
The DLI, Boiler Division, has reported that all water-pressure tanks using air as a pressurant, located in
commercial or public buildings, or in apartment buildings larger than a six-plex, must be inspected
and certified by the DLI. Pressure tanks located on public supplies serving businesses, churches, and
communities are included.
Pressure tanks used in commercial or public buildings which are 120 gallons or larger must be rated by
the ASME. Tanks with volumes less than 5 cubic feet and having a 100 pound, ASME relief valve are
exempt from the ASME tank rating requirements.
STAT AUTH: MS s 103I.101; 103I.111; 103I.205; 103I.221; 103I.301; 103I.401;
103I.451; 103I.501; 103I.525; 103I.531; 103I.535; 103I.541; 103I.621; 144.05;
144.12; 144.383; 157.04; 157.08; 157.09; 157.13
HIST: 17 SR 2773; 33 SR 211
4725.5400 [Repealed, 17 SR 2773]
4725.5450 VENTING WATER-SUPPLY WELLS.
Subpart 1. Venting exceptions. A water-supply well must be vented unless the
well:
A. is a flowing well;
B. casing is used as a suction pipe;
C. has a packer jet assembly;
D. is used as a remedial well; or
E. is constructed with a watertight seal in lieu of a casing extension as specified
in part 4725.4350, subpart 2.
A vent is required to eliminate negative pressure from occurring when the pump starts and the water level
drops. Negative pressure can draw in contaminants through electrical conduits or other connections to the
casing. A vent also exhausts toxic gases such as hydrogen sulfide which can cause asphyxiation in
confined spaces such a well house, and exhausts explosive gases such as methane. Vents are not
required for flowing wells, wells with packer-jet pumps, remedial wells, wells that use the casing as a
suction pipe, and wells in areas where the regional flood level is more than 5 feet above the ground
surface.
The venting requirement does not prohibit the use of a drawdown seal installed below the static water
level in a well. However, the use of drawdown seals above the static water level is prohibited and the use
of drawdown seals is generally not recommended.
Subp. 2. Vent construction. A well vent must:
A. be constructed of materials complying with parts 4725.2250 to 4725.2650, or
4725.5150, subpart 1;
B. have watertight joints and terminate at least five feet above the regional
flood level unless provided with a watertight seal as specified in part 4725.4350,
subpart 2;
339
C. terminate a minimum of 12 inches above the established ground surface or
the floor of a building as specified in part 4725.2175, except that a vent for a
community public water-supply well must terminate a minimum of 18 inches above
the established ground surface and the floor of a building as specified in part
4725.2175;
D. be screened with a noncorrosive mesh screen having openings of 1/16 -inch
or less and pointed downward; and
E. be connected to the casing according to part 4725.4850.
The vent must be constructed of well casing materials (Minnesota Rules, parts 4725.2250 through
4725.2650), or materials approved for pump suction and discharge lines (Minnesota Rules,
part 4725.5150, subpart 1).
The regional flood is the 100-year flood and is explained in Minnesota Rules, part 4725.0100,
subpart 40b. If the flood level is more than 5 feet above the ground surface, Minnesota Rules,
part 4725.4350, subpart 2, allows the casing to terminate: 10 feet above the ground if a watertight seal
without a vent is installed; 2 feet above the ground if an outer cement-grouted protective casing and
waterproof threaded cap or compression seal are installed; or 2 feet above ground if a sealed, flowing well
pitless, and a waterproof nonvented well cap are installed
The vent and the top of the casing must both terminate at least 12 inches above grade, or 12 inches above
the floor of a well house. If the casing is exactly 12 inches above the ground surface and an overlapping
cap with a built-in underside vent is used, the vent will terminate too low. In this case, the casing should
be left more than 12 inches above-grade.
The vent for a community public water-supply well must be 18 inches above-grade as required in
Minnesota Rules, part 4725.5850.
Screened openings must be 16 mesh or less (16 squares per inch, essentially window screen size) and be
constructed of a noncorrosive material such as brass, aluminum, or fiberglass. Upside down “U”-shaped
vents or “mushroom-type” vents may be used.
All vents, whether constructed on a water-supply well or another type of well, must meet the requirements
of this part. The practice of drilling a hole in a casing is not an approved venting method.
Subp. 3. Screened vents. A screened vent incorporated into the underside of a
well cap or cover may be used.
Minimum vent diameter or open area sizes have not been established; however, very small diameter vents
on the underside of caps may provide inadequate air flow and result in the freezing of the vent in winter
or plugging with debris. Also, it has been observed that some under-cap screens are not securely fastened
to the cap and can fall out. Care should be taken to use a vent of adequate size, quality, and construction.
340
Subp. 4. Gas. Any toxic or flammable gas must be vented from the well to the
outside atmosphere.
STAT AUTH: MS s 103I.101; 103I.111; 103I.205; 103I.221; 103I.301; 103I.401;
103I.451; 103I.501; 103I.525; 103I.531; 103I.535; 103I.541; 103I.621; 144.05;
144.12; 144.383; 157.04; 157.08; 157.09; 157.13
HIST: 17 SR 2773; 33 SR 211
4725.5475 HYDROFRACTURING WATER-SUPPLY WELLS.
Subpart 1. Scope. This part applies to hydrofracturing a water-supply well, as
defined in part 4725.0100, subpart 30f. A remedial water-supply well, or other
well or boring regulated by this chapter, must not be hydrofractured.
Hydrofracturing must be done by a well contractor licensed according to
Minnesota Statutes, section 103I.525.
Hydrofracturing is the process of injecting water into (igneous or metamorphic) bedrock at pressures high
enough to open existing fractures or create new fractures in order to increase water yield. Hydrofracturing
uses one or more (typically two) inflatable packers to isolate a portion of the formation. This is done to
concentrate the pressures in a more localized area, and avoid fracturing areas that may compromise the
integrity of the well, produce sediment, or produce little water. The packer (or packers) is inflated, and
high pressure water, commonly from 500 to 2,000 psi, is pumped into the formation. The water may open
existing fractures wider, propagate fractures further, and in some cases create new fractures.
Hydrofracturing is not always successful, and carries risks. Hydrofracturing involves high pressures
capable of damaging wells, affecting nearby wells, and causing injuries to workers and bystanders.
Hydrofracturing a dry hole is rarely successful. Wells producing a few tenths of a gallon per minute to a
few gallons per minute are the typical candidates for hydrofracturing. A hydrofracturing job is often
considered successful if the yield increases from 1/2 to a few times the original.
Minnesota Rules, Chapter 4725 allow only a water-supply well completed in igneous or metamorphoric
rock to be hydrofractured. However, a variance may be granted for other wells or borings in appropriate
situations. The variance allows for review of the specific circumstances. Only a “full” licensed well
contractor (not a “limited” contractor) may hydrofracture.
Subp. 2. Injection materials, water, and proppants
A. Water used for hydrofracturing must be potable water containing a chlorine
residual. The use of surface water, unless obtained from a public water system, is
prohibited.
B. Additives must meet the requirements of ANSI/NSF Standard 60-2003e as
determined by a person accredited by the ANSI under ANSI Standard Z34.1-1993.
C. Proppants may be used to hold the joints and fractures open, and must be
inert, clean, and nontoxic materials, including chlorinated, non-calcareous,
washed sand.
The rules do not allow surface water to be used for hydrofracturing, unless the surface water is the treated
potable water from a public system that draws its supply from a surface water source.
341
“Proppants” are granular materials sometimes injected along with the water to hold fractures open.
Proppants are not commonly used in Minnesota, but when they are, round quartz sand grains are typically
used. Ceramic beads are less frequently used.
Subp. 3. Restrictions. The following restrictions apply when hydrofracturing.
A. The upper packer must be a minimum of 50 feet below the established
ground surface.
B. Hydrofracturing must not occur inside a casing. The upper packer must be a
minimum of ten feet below the lower termination of a casing.
C. Hydrofracturing must only be done in igneous or metamorphic bedrock.
D. A water-supply well must not be hydrofractured unless located according to
the isolation distances in parts 4725.4350 and 4725.4450.
The restrictions are designed to prevent damage to the well casing, and prevent interconnection of surface
or near surface contaminants with the well.
Examples of igneous or metamorphoric bedrock include granite, gneiss, basalt, and quartzite. Sandstone
and limestone are not igneous or metamorphic rocks.
In order to hydrofracture a new or old well, the well must be in compliance with all of the isolation or
“setback” distances in rule.
A notification or permit is not required for hydrofracturing; however, reporting is required as described
below.
Subp. 4. Requirements. The following requirements apply when hydrofracturing.
The person hydrofracturing must:
A. remove additives injected during hydrofracturing;
B. disinfect a hydrofractured water-supply well upon completion of
hydrofracturing, according to part 4725.5550.
C. collect a water sample from a hydrofractured water-supply well used for
drinking or other potable purposes, and test the sample according to part
4725.5650; and
D. complete and submit a well and boring construction record, or amended
record, within 30 days of completion of hydrofracturing.
Additives do not include proppants, but do include any treatment chemicals injected.
The disinfection and water sample requirements are the same as for a new well since the hydrofracturing
opens the well, injects water, and creates fractures that may connect new water sources.
If hydrofracturing is occurring at the time of well construction, a single well and boring construction
record using the official preprinted form should be completed. If hydrofracturing occurs at a later date,
and the contractor who drilled the well is hydrofracturing the well, the contractor may photocopy the
original well record, amend the record to report the hydrofracturing, and submit the amended photocopy.
If the contractor hydrofracturing the well did not drill the well, a “work copy” Well and Boring Record
342
should be completed. A search should be made for the Minnesota unique well number by looking for the
well tag, searching County Well Index, or asking the well owner. If the Minnesota unique well number is
found, it should be reported on the work copy; otherwise the well number should be left blank.
STAT AUTH: MS s 103I.101; 103I.111; 103I.205; 103I.221; 103I.301; 103I.401;
103I.451; 103I.501; 103I.525; 103I.531; 103I.535; 103I.541; 103I.621
HIST: 33 SR 211
4725.5500 [Repealed, 17 SR 2773]
343
End
of
Pitless, Pumps, Vents, Hydrofracturing Section
344