NR 811.53(2)(c)8.8. All buried piping shall be maintained under a positive pressure greater than the elevation of the ground surface. NR 811.53(2)(c)10.10. Consideration shall be given to installing a butterfly valve in the inlet piping to control the water flow rate and to minimize air entrainment. NR 811.53(2)(c)12.12. The inlet piping shall be supported separately from the tower’s main structural support. NR 811.53(2)(d)2.2. The air inlet to the blower and the tower discharge vent shall be screened and provided with a downturned, hooded or mushroom cap that protects the screen from the entrance of extraneous matter including insects and birds, obnoxious fumes, all types of precipitation and condensation, and windborne debris or dust. The screens shall be constructed of 24-mesh corrosion resistant material and installed at a location least susceptible to vandalism or damage. The air inlet shall also be provided with a dust filter. NR 811.53 NoteNote: It is recommended that a 4-mesh corrosion resistant screen be installed in front of the 24-mesh screen on the air inlet system.
NR 811.53(2)(d)3.3. The blower shall be provided with a weather-proof motor, a tight housing, and an adequate foundation. NR 811.53(2)(d)4.4. An air flow meter or department approved alternative method for determining the air flow shall be installed on the air inlet piping. NR 811.53(2)(d)5.5. A positive air flow sensing device and a pressure gauge shall be installed on the air inlet line to the tower. If positive air flow is not detected, the device shall automatically shut down the water flow. NR 811.53(2)(d)6.6. A backup motor for the blower shall be readily available where the tower is used to maintain primary drinking water standards. NR 811.53(2)(e)1.1. The tower shall be provided with a sufficient number of access ports with a minimum diameter of 24 inches to facilitate inspection, media replacement, media cleaning, and maintenance of the interior. NR 811.53(2)(e)2.2. A means shall be provided for cleaning the packing material should it become fouled. NR 811.53(2)(e)3.3. Any clearwell or reservoir constructed to receive water from a tower shall be constructed to meet the potable water reservoir requirements of s. NR 811.64. NR 811.53(2)(e)4.4. The tower shall be designed and constructed so that it can be extended without major reconstruction. NR 811.53(2)(e)5.5. A means of bypassing the tower shall be provided unless the requirement is waived by the department because the water system has access to other water sources that can provide an average day supply of water at minimum. NR 811.53(2)(e)6.6. Disinfection application points shall be provided on the tower inlet and outlet piping. NR 811.53(2)(e)7.7. Any water passed through the tower shall be continuously disinfected. If raw water has bacteriological issues, the department may require a minimum of 4-log inactivation of viruses as determined by the department on a case-by-case basis. NR 811.53(2)(e)8.8. The water supply pump or pumps, blower motor, disinfection equipment, and the positive air flow sensing device shall be electrically interconnected to operate in series. NR 811.53(2)(e)9.9. Adequate packing support shall be provided to allow the free flow of water and to prevent packing deformation. NR 811.53(2)(e)10.10. Adequate auxiliary power shall be provided to operate the air blower and disinfection equipment during power failures unless the requirement is waived by the department because the water system has access to other water sources that can provide an average day supply of water at minimum or operation of the tower is not mandatory to meet primary drinking water standards. NR 811.53(2)(e)11.11. The tower shall be provided with an adequate foundation and lateral support to prevent overturning due to wind loading. NR 811.53(2)(e)12.12. The equipment shall be located within a secure building or within a locked security fence to prevent vandalism. NR 811.53(2)(e)13.13. An access ladder with safety cage shall be provided to allow access and inspection of all areas of the tower. NR 811.53(2)(e)14.14. Exhaust air shall be discharged directly to the outside atmosphere and in a location that will be protective of public health. Air emissions controls shall be provided if necessary to meet air quality standards. NR 811.53(2)(e)15.15. Noise control equipment shall be provided where systems are located in residential areas.