Current through Supplement No. 394, October, 2024
1.
Pumphouse
appurtenances. The installation of necessary appurtenances for public
wells shall be as illustrated in pump installation details contained in the
diagrams attached to this chapter.
a. Floor
drain. The pumproom floor shall be watertight and shall slope away from the
pump base. The pumproom floor shall be provided with a floor drain discharging
to a sump at least twenty-five feet [7.62 meters] from the well.
b. Vents. Provisions shall be made for
venting the well casing to the atmosphere. There shall be no holes in the pump
base which might allow wastewater or other material to enter the well. A
breather tube shall be installed of sufficient size to permit air to enter and
leave the well freely with the changing of water elevation caused by starting
and stopping the pump. The breather tube shall terminate in a full
one-hundred-eighty-degree bend at least eighteen inches [45.72 centimeters]
above the floor, securely screened with sixteen mesh wire screen. If the
breather tube or a depth gauge line passes through the base of the pump or
through the seal connection into the well, the hole about the tube shall be
sealed.
c. Water level measurement.
An access plug for a measuring tape or an air line and drawdown gauge for
determining location of the water level shall be installed during the
installation of the pump on all public wells. Installation of permanent water
level measuring equipment shall be made using corrosion-resistant materials
firmly attached, in a vertical position, to the drop pipe or pump column in
such a manner as to prevent entrance of foreign materials. The air line shall
extend from the top of the well to several feet [meters] below the lowest
anticipated water level. The length of the air line shall be accurately
measured and the length recorded.
2.
Cutting of well casing. No
casing shall be cut off or cut into below ground level except to install a
pitless unit or adapter.
3.
Pitless unit and adapter.
a.
Pitless unit. Pitless units designed to replace a section of well casing must
meet the standards of the national sanitation foundation or the water systems
council and must:
(1) Be factory fabricated
from point of connection with the well casing to the unit cap or cover. The
materials used must be durable, at least equal in quality to the well casing,
to prevent excessive corrosion.
(2)
Form an unbroken extension of the well casing from the point of discharge to a
point above ground level as specified for upper well terminals.
(3) Have an inside diameter equal to or
greater than the inside diameter of the well casing to facilitate work and
repair on the well, pump, or well screen. Any deviation from this paragraph
must be approved in writing by the department.
(4) Conduct water from a well casing without
exposing the well to contamination through openings in the casing.
(5) Have access to the casing for
disinfection of the well.
(6) Be
capped with a cover having a downward flange which will overlap the edge of the
unit. The cover must be securely fastened to the unit and must be sufficiently
snug to the unit to be verminproof or watertight if required.
The cover must provide for watertight entrance of electrical
cables, vent piping, and an air line or a tap for wetted tape measurements of
depth to water level of a well.
(7) Be installed by threaded, welded, or
compression flange gasketed connection to the cutoff casing. The threaded,
welded, or compression flange gasketed connection to the cutoff casing must be
watertight. If the connection to the casing is to be a field weld, the
factory-assembled unit must be designed specifically for field
welding.
(8) Have all field
connections between the pitless unit and the water service pipe threaded,
flanged, or mechanical joint.
b. Pitless adapter. Commercially manufactured
clamp-on or weld-on pitless adapters for attachment to the exterior of a well
casing may be installed when approved by the department. Pitless adapters must
be installed according to manufacturer's specifications and meet the standards
of the national sanitation foundation. A list of approved pitless adapters is
available from the department.
(1) Pitless
adapters must be constructed and installed so as to prevent the entrance of
contaminants into the well or water supply through openings in the well
casing.
(2) The pitless adapter
must provide adequate clearance within the well to permit insertion and
withdrawal of the pump and system components through the upper terminal of the
well casing.
(3) The pitless
adapter must be connected to the well casing with clamps-and-gasket or by
welding and must be watertight. To assure a watertight connection between the
pitless adapter and the well casing, care must be used in cutting the hole in
the well casing, preferably with a hole-cutting saw. All burrs from the cutting
process must be removed. Both the outside and the inside surfaces of well
casing surrounding the hole must be smooth.
(4) A pitless cap or cover must enclose the
upper terminal of the well casing. The cap, entrance of electrical cables, vent
piping, air lines, etc., must be as specified for pitless units.
(5) All field connections between the pitless
adapter and the water service pipe must be threaded, flanged, or mechanical
joint.
(6) All other aspects of
pitless adapter requirements must be as specified for pitless units.
c. Freezing. Water service piping
must be installed below recorded frost penetration. A minimum depth of seven
feet [2.28 meters] below grade is recommended to prevent freezing.
4.
Over-the-well
pumps. Power-driven pumps located over a well shall be installed on a
concrete base of sufficient height to permit the outside casing to extend one
inch [2.54 centimeters] above the concrete base. On all public water wells, the
annular opening between the drill hole and casing shall be filled with cement
grout before the pump base and pumphouse floor are constructed. If the well is
of the gravel wall type, the outer casing shall extend at least twelve inches
[30.48 centimeters] above the pumproom floor with suitable provisions made for
adding gravel. The inner casing shall extend one inch [2.54 centimeters] above
the pump base. Note diagrams no.1 and no.2, pump installation details, in the
diagrams attached to this chapter.
A sanitary well seal shall be installed at the top of the
well casing to prevent the entrance of contaminated water or objectionable
material.
5.
Pump
column. A separate pump column, suction or discharge pipe shall be
installed inside the well casing in all instances, whether the well is to be
pumped by suction, airlift, or deep well pump.
6.
Submersible pumps. The
discharge line installed inside of the well casing must meet the standards for
ferrous or nonferrous well casing in subsections 2 and 3 of section
33.1-18-01-06. The discharge
line shall leave the well at the top of the casing. The opening between the
discharge line and casing or pipe sleeve shall be sealed watertight with an
expanding rubber seal or equivalent device. When an underground discharge is
desired, a properly installed pitless unit or, when approved by the department,
a pitless adapter shall be used.
The electrical cable shall be firmly attached to the pump
riser at intervals of twenty feet [6.10 meters] or less.
When a check valve is not part of the pump, a check valve
shall be installed on the pump discharge line within the well.
A check valve on the pump discharge line is not required on
nonpressurized wells for livestock use that would be damaged by freezing, when
an airgap or other cross-connection control protection is provided.
7.
Offset pumps.
Pumps offset from public wells shall be located in an aboveground pumphouse or
other building.All portions of suction lines buried below the ground surface
between the well and the pump shall be enclosed in a protective pipe of
standard thickness and be sealed watertight at both ends.
This requirement shall be considered satisfied if the suction
line lies within a pressure discharge line.
Offset pumps for private wells may be located in a basement
provided that the pumps and all suction pipes are elevated at least twelve
inches [30.48 centimeters] above the floor.
8.
Hand pumps. Hand pumps shall
be of the force type equipped with a packing gland around the pump rod, a
delivery spout which is closed and downward directed, and a one-piece bell-type
base which is part of the pump stand or is attached to the pump column in a
watertight manner.
The bell base of the pump shall be bolted with a gasket to a
flange which is securely attached to the casing or pipe sleeve.
9.
Pump controls.
a. Public water wells. Pump controls for
public water wells must be installed in accordance with the manufacturer's
recommendations as shown on approved plans and specifications.
b. Private water wells. Pump controls for
private water wells should be installed in accordance with manufacturer's
recommendations and must include:
(1) A
pressure-activated pump switch.
(2)
A thermal overload switch.
(3) A
flow control orifice or a low water level cutoff switch on all pumps having an
output in excess of the well capacity.
(4) A pressure relief valve on positive
displacement pumps.
(5) The
installation of necessary appurtenances for private water wells should be as
illustrated in diagram no.4 - pitless unit and appurtenances for private
wells.
General Authority: NDCC 43-35-19, 43-35-19.1;
S.L.2017, ch.199, § 1
Law Implemented: NDCC 43-35-19, 43-35-19.1;
S.L.2017, ch.199, §§ 45,
46
