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.

NR 811.35(6)(d)(d) The pitless unit shall be installed in accordance with the requirements of s. NR 812.31 (3) (a).

NR 811.35(6)(e)(e) Pitless units shall be installed by a licensed pump installer. The installed pitless unit shall be tested and proven watertight under a pressure of not less than 14 psig. The pressure shall be maintained for a minimum of 30 minutes. Additionally, any leaks detected shall be sealed during the pressure test. The installer shall notify the department a minimum of 48 hours before performing the pressure testing so that a department employee may witness the test. A report on the results of the pressure testing, signed by a licensed pump installer, shall be submitted to the department before placing the well in service.

NR 811.35(6)(f)(f) A certification by the licensed pump installer that installed the pitless unit confirming that the well was originally grouted to the ground surface and that the requirements of pars. (b) and (c) were met, shall be submitted to the department along with the pressure testing report and a copy of the well construction report.

NR 811.35(6)(g)(g) Backfilling of the excavation shall commence as soon as practical after the installation and a successful pressure test of the pitless unit.

NR 811.35(6)(h)(h) For slab-on-grade enclosures, a below grade length of pump discharge piping from the pitless unit, sufficient to extend beyond the enclosure, shall be installed prior to backfilling of the excavation and construction of the concrete floor slab. The buried piping shall be temporarily capped in a sanitary manner unless the piping is immediately extended and connected to the remainder of the system. During the installation of the discharge piping, if the sampling faucet riser pipe is not installed within the well and pitless unit, a metal riser pipe shall be extended vertically from the below grade discharge piping to terminate at a height a minimum of 12 inches above the top of the future concrete floor. The riser pipe shall be fitted with a frost-proof, down-turned, metal, smooth-end sampling faucet or shall be temporarily capped.

NR 811.36(1)(a)(a) For wells without pitless units, a metal vent pipe shall be installed that terminates in a 24-mesh corrosion resistant screened “U” bend or mushroom cap at least 24 inches above the floor. The vent pipe diameter shall be a minimum of 2 inches for well casings 10 inches in diameter and larger. The department may, on a case-by-case basis, allow smaller diameter well vents on existing installations if water drawdown has not compromised the sanitary seal or require larger diameter well vents for wells with significant water level drawdown. Vent piping shall be welded watertight to the side of the well casing a minimum of 4 inches above the floor and may extend through a concrete pump base or collar where one is present. Alternatively, vent piping may project through a well seal or pump discharge head if the well seal or discharge head is watertight and will facilitate the installation of the vent pipe.

NR 811.36(1)(b)(b) For wells with pitless units, a metal vent pipe shall be installed which terminates in a 24-mesh corrosion resistant screened “U” bend or mushroom cap at least 24 inches above the floor. The pitless unit vent area shall be equal to or greater than the area provided by a 2-inch diameter vent pipe for pitless units 10 inches in diameter or larger. Vent piping shall extend above or be incorporated into the top of the pitless unit or be welded watertight to the side of the pitless unit a minimum of 4 inches above the floor and may extend through a concrete pump base or collar where one is present.

NR 811.36(1)(c)(c) If the well is flowing, the vent shall terminate above the artesian water level or a suitable automatic valve shall be provided.

NR 811.36(2)(a)(a) Provisions shall be made for measurement of static and pumping water levels in the completed well by the use of an electric depth gauge, pressure transducer or an air line attached to the pump column and an altitude gauge.

NR 811.36(2)(b)(b) The installation shall be constructed to prevent entrance of foreign material.

NR 811.36(2)(c)(c) Air lines may not be installed through vent pipes unless justified when modifications are being made to existing installations, the minimum 2-inch diameter vent pipe area is maintained where applicable, and the specific approval of the department is obtained.

NR 811.37(1)(1) Buried lines. Adequate positive pressure shall be maintained on all buried piping. Pump suction and discharge lines that are to be buried shall be designed so that the line is under a continuous pressure head that is higher than the elevation of the ground surface under all operating conditions. Lines where a positive pressure head that is higher than the elevation of the ground surface cannot be maintained may be installed if the lines are encased for their entire length in a watertight pipe conduit or a tunnel. Buried lines that, under all operating conditions, are not under a positive pressure head that is higher than the elevation of the ground surface and are not encased for their entire length in watertight pipe conduit or a tunnel are not permitted.

NR 811.37(3)(3) Location of appurtenances. Pump discharge piping containing appurtenances such as valves, sampling faucets, water meters, and other equipment shall be located above the ground surface.

NR 811.37(4)(4) Pump-to-waste. All wells and high-lift pump stations shall be provided with a means to pump to waste. This shall be a plugged tee or blind flange or a shut-off valve followed by a hose connection installed on the pump discharge piping inside the pump station. For municipal and subdivision water systems, a valve and hydrant may be installed outside the pump station on the buried pump discharge piping.