NR 811.48(1)(b)(b) Capacity. The chlorinator capacity shall be such that a free chlorine dose of at least 2 mg/L can be attained when maximum flow rates coincide with anticipated maximum chlorine demands. Liquid chemical feed equipment shall be designed to operate in accordance with the requirements under s. NR 811.39 (2) (c). Solution-feed-gas-type chlorination chemical feed equipment shall be designed to operate between 10 percent and 70 percent of the rotameter capacity. This may require that 2 rotameters be provided, one for normal feed rates and one for emergency feed rates. For all chemical feed systems, the emergency feeder setting shall be designed to provide a minimum of 2 mg/L of chlorine.

NR 811.48(1)(c)(c) Standby equipment. Where chlorination is necessary for protection of the water supply, standby equipment of sufficient capacity shall be available to replace the largest unit during shut-downs. Spare parts shall be made available to replace parts subject to scaling, wear, and breakage.

NR 811.48(1)(d)(d) Automatic proportioning. Automatic proportioning chlorinators shall be required where the rate of flow of the water is not reasonably constant or where the rate of flow of the water is not manually controlled.

NR 811.48(2)(a)(a) Chlorine shall be applied at a point which will provide the maximum contact time. Provisions shall be made to minimize short-circuiting.

NR 811.48(2)(b)(b) At plants treating surface water, piping provisions shall be made for applying chlorine to the raw water, settled or clarified water, filtered water, and the plant effluent.

NR 811.48(2)(c)(c) At plants treating groundwater, provision shall be made for applying chlorine to the raw water, the clearwell inlet, and the discharge piping as applicable.

NR 811.48(2)(d)(d) At plants treating groundwater where CT is required by the department, provision shall be made for applying chlorine to the raw water, at the inlet to all CT reservoir detention basins, and the high-lift pump discharge piping as required by the department.

NR 811.48(3)(a)(a) Chlorine residual testing methodology shall be as specified in s. NR 809.563 (2), Table R. The equipment shall enable measurement of residuals to the nearest 0.1 mg/1 in the range below 0.5 mg/1 and to the nearest 0.2 mg/1 between 0.5 mg/1 to 2.0 mg/1.

NR 811.48 NoteNote: It is recommended that all systems, at a minimum, use an instrument using the DPD colorimetric method with a digital readout and a self contained light source. Automatic chlorine residual pacers and recorders are recommended where the chlorine demand varies appreciably over a short period of time.

NR 811.48(3)(b)(b) Water systems that rely on chlorination for inactivation of bacteria or other microorganisms present in the source water shall have continuous chlorine residual analyzers and other equipment that automatically shut down the facility when the chlorine residuals required by the department are not met. The department may approve less than continuous monitoring for municipal water systems serving 3,300 or fewer people and other-than-municipal water systems on a case-by-case basis provided that replacement measures or practices are implemented to provide comparable public health protection.

NR 811.48(4)(4) Gas chlorinator piping. The water supply piping shall be designed to prevent contamination of the treated water supply by sources of impure or unknown quality. Pipes carrying elemental liquid or dry gaseous chlorine under pressure shall be Schedule 80 seamless steel tubing or other materials recommended by the Chlorine Institute. PVC pipe may not be used. Chlorine solution piping and fittings shall be rubber, PVC, polyethylene, or other materials recommended by the Chlorine Institute.

NR 811.48(5)(a)(a) Chlorine gas feed and storage installations shall be separated from other operating areas by gas-tight rooms or enclosures in order to prevent injury to personnel and damage to equipment.

NR 811.48(5)(b)(b) Chlorine gas rooms shall be provided with a safety glass inspection window installed in an interior wall or exterior door to permit viewing of the interior of the room and the equipment.

NR 811.48(5)(c)(c) Chlorine gas rooms shall be provided with a minimum of one door having emergency or panic hardware opening outward to the building exterior. Rooms may have additional doors to the building exterior.