Pump installation for water wells

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.