NR 811.34(1)(1) Pumping capacity to meet peak demand. The gallon per minute discharge rates of the pump or pumps shall be capable of meeting the peak demand rate when there is no elevated storage and the pressure tank storage volume will be reduced due to the installation of the variable output control device or devices. NR 811.34(2)(2) High pressure cut-out switch. A high pressure cut-out switch shall be installed on the pump discharge piping to stop the pump motor when a preset maximum discharge pressure is detected if the pump shut-off head at the maximum possible speed will exceed the safe working pressures of the piping and appurtenances. NR 811.34(3)(3) Pressure relief valve. A pressure relief valve shall be installed on the pump discharge piping sized to allow adequate pressure to be relieved if a malfunction that would cause the pump to discharge at the maximum possible rate would result in pressures exceeding the safe working pressures of the piping and appurtenances. NR 811.34(4)(4) Backup controls. All water systems supplied by one well or booster pump shall be provided with a redundant means of controlling the operation of the pump motor. Such means may include the installation of an electrical bypass of the variable output control device along with the installation of pressure switches or other department approved installation. NR 811.34(5)(5) Flow pacing for chemical feed pumps. Where pump discharge rates will vary after initial startup of the pump, all chemical feed pumps shall be paced from a flow proportional signal from a water meter. This requirement is in addition to any requirement for the chemical feed pump to be wired to operate in series with the pump motor starter and any required secondary chemical feed pump control mechanism. NR 811.34(6)(6) Adequate storage. Storage shall meet the following requirements when there is no elevated storage or the minimum pressure tank storage volume normally required by s. NR 811.61 (7) will be reduced due to the installation of one or more variable output control devices. NR 811.34(6)(a)(a) For other-than-municipal water systems and small municipal water systems not provided with elevated storage, the gross pressure tank storage volume shall be a minimum of 2.5 times the design pump output in gallons per minute. When a vertical turbine pump requiring prelubrication or an auxiliary power source with an automatic transfer switch is employed, calculations shall be provided to the department to demonstrate that the storage volume is adequate to provide the necessary time for the prelubrication to occur or for the auxiliary power source to come on line before the system pressure drops below 20 psi as a result of a brief electrical power outage. NR 811.34(6)(b)(b) For a control valve type of installation, the gross pressure tank storage volume shall be a minimum of 5 times the design pump output in gallons per minute to prevent the pump motor from over-heating. NR 811.34(6)(c)(c) For booster or high-lift pump installations where the pump is discharging to a distribution system without elevated storage, the gross pressure tank storage volume shall be a minimum of 2.5 times the design pump output in gallons per minute. NR 811.34(6)(d)(d) As an alternate to pars. (a) to (c), the department may approve other proposed pressure tank storage volumes when justified by supporting information submitted to the department. NR 811.34(6)(e)(e) Control or piping and valve measures shall be provided to prevent water from becoming stagnant in pressure tanks. The variable output control device shall be programmed to allow a 10-psi pressure drop from pump ‘off’ mode to pump ‘on’ mode to allow time for the pressure tanks to empty. NR 811.34(6)(f)(f) Additional storage volume shall be provided for adequate operation of water treatment equipment including storage volumes necessary to obtain required reaction or disinfection detention times in detention vessels. The storage volumes shall be calculated by the design engineer assuming the pump or pumps are discharging at the maximum possible rate. NR 811.34(7)(7) Ventilation. Automatically controlled forced air ventilation shall be installed for any room where an electronic variable output control device will be installed and room temperatures will exceed 90 degrees F. NR 811.34(8)(8) Measures to prevent damage from corrosive chemicals. The installation of an electronic variable output control device may not be allowed in a corrosive environment. Electronic variable output control devices may not be installed in the same room with fluoride acid chemical feed equipment. Preventive measures such as adequate sealing and ventilation of chemical containers and solution tanks shall be taken to minimize the production of corrosive fumes from other kinds of chemical feed installations, including sodium hypochlorite. The installation of a separate chemical feed room or the installation of room or chemical feed system ventilation improvements may be required by the department where significant damage from corrosive fumes has been documented. NR 811.34(9)(9) Dehumidification or air conditioning. Dehumidification or air conditioning equipment shall be installed in any room where an electronic variable output control device will be installed and excessive moisture will be a concern. NR 811.35NR 811.35 Pitless units. Pitless units shall be installed in a manner to provide equivalent security, sanitary protection, accessibility, and operational flexibility to an above grade pump discharge installation and in accordance with the requirements of this section and as shown in Figure No. 7 in the Appendix. NR 811.35(1)(1) Termination. Pitless units shall terminate a minimum of 12 inches above a concrete floor as required by ss. NR 811.12 (1) and 811.32 (1) (a). If the vent assembly is built into the pitless unit, the portion of the pitless unit where the bottom of the vent assembly is located shall be terminated a minimum of 24 inches above the concrete floor. Pitless units shall be provided with a protective concrete collar where they pass through the concrete floor as required by s. NR 811.32 (1) (c). The exterior exposed conduit pipe for the pump wiring shall be rigid steel and the conduit pipe incorporated into the concrete collar. NR 811.35(2)(2) Enclosure. The exposed portion of a pitless unit shall be surrounded by a weather resistant, watertight, locked, and vented enclosure secured to a concrete floor as required by s. NR 811.25 (1) (i). The top surface of the concrete floor shall be located a minimum of 6 inches above the finished grade. NR 811.35(3)(3) Appurtenances. The top of the pitless unit shall be sealed sanitarily in accordance with s. NR 811.32 (1) (b), provided with a well vent and water level measuring equipment in accordance with s. NR 811.36, and shall be provided with a frost-proof down-turned metal smooth-end sampling faucet terminating above the top of the pitless unit and a minimum of 12 inches above the concrete floor of the enclosure unless the sampling faucet is installed remote from the pitless unit in accordance with sub. (6) (h). NR 811.35(4)(4) Discharge piping. Discharge piping from a pitless unit shall meet the following requirements: NR 811.35(4)(a)(a) The discharge piping from the pitless unit shall be directed to a separate building located above grade where all of the applicable pump discharge piping appurtenances shall be installed in accordance with s. NR 811.37 and Figure No. 7 in the Appendix. NR 811.35(4)(b)(b) The discharge piping from the pump in the well to the above grade pump discharge piping shall remain pressurized at all times. No provisions for drain back of the discharge piping may be allowed. A shut-off valve shall not be installed in the buried portion of the pitless unit discharge piping unless approved by the department as part of a pump-to-waste installation. NR 811.35(4)(c)(c) The buried portion of a pitless unit discharge piping along with any joints or fittings shall be ductile iron, steel, or plastic piping meeting at minimum the AWWA pressure class 150 water main standards required under s. NR 811.69. Plastic piping shall not be used in areas where soil or groundwater contamination may be present. Plastic piping shall be transitioned to metal piping within 12 inches above the floor of the building into which it will be directed, under par. (a), unless minimum schedule 80 PVC pipe is installed in the building as allowed under s. NR 811.28 (5) (b). NR 811.35(5)(5) Check valves. A check valve shall be installed in the submersible pump discharge piping in the well immediately above the pump. A check valve shall not be installed in the buried pitless unit discharge piping. A check valve may not be installed in the above grade pump discharge piping unless preceded by the pump on and off controls, or one or more pressure tanks, or unless the department approves an alternate method to maintain positive pressure in the piping under all operating conditions. NR 811.35(6)(a)(a) Pitless units shall be factory assembled and pressure tested, full length units, with the make and model number having received individual department approval for use. The inside diameter of the pitless unit shall not be smaller than the inside diameter of the well casing pipe as required by s. NR 812.31 (2) (b). NR 811.35(6)(b)(b) The department may not approve installation of a pitless unit unless any temporary outer well casing is totally removed from the well during the well construction process. Pitless units shall be attached only to the protective grouted well casing, including wells constructed with gravel packed screens. NR 811.35(6)(c)(c) The top surface of the remaining well grout shall be no greater than one foot below the installation depth of the pitless unit, which is the well casing cut-off depth.