NR 811.575(14)(14) Appropriate test equipment for the target contaminant shall be provided to determine treatment effectiveness. NR 811.575 HistoryHistory: CR 22-074: cr. Register January 2024 No. 817, eff. 2-1-24. NR 811.58NR 811.58 Stabilization. Water that is unstable to the extent of causing corrosion or deposition problems in the distribution system, whether a result of natural causes or water treatment processes, shall be stabilized. The following standards shall apply: NR 811.58(1)(a)1.1. A total detention time of 20 minutes or as approved by the department. NR 811.58(1)(a)2.2. Two compartments, with a depth that will provide a diffuser submergence not less than 7.5 feet nor greater than recommended by the manufacturer and as follows: NR 811.58(1)(b)(b) The design shall prevent carbon dioxide from entering the plant from the recarbonation and reaction chamber. NR 811.58(1)(c)(c) Plants generating carbon dioxide from combustion shall have open top recarbonation tanks in order to dissipate carbon monoxide gas. NR 811.58(1)(d)(d) Provisions shall be made for draining the recarbonation basin and removing sludge. NR 811.58(2)(2) Phosphates. Phosphates may be used for sequestering calcium in lime softened water, corrosion control and in conjunction with alkali feed following ion exchange softening. When used: NR 811.58(2)(b)(b) Phosphate chemicals shall meet the NSF/ANSI Standard 60 requirements. NR 811.58(2)(c)(c) Stock phosphate solution shall be kept covered and disinfected by carrying an approximate 10 mg/1 chlorine residual. The department may exempt phosphate solutions having a pH of 2.0 or less from this requirement. NR 811.58(2)(e)(e) The total phosphate applied may not exceed 10 mg/1 as PO4. NR 811.58(3)(3) Split treatment. If approved by the department, a lime-soda water treatment plant may be designed using ‘split treatment’ in which raw water is blended with lime-treated water to partially stabilize the water. Treatment plants designed to utilize ‘split treatment’ shall contain facilities for further stabilization by other methods. NR 811.58(4)(4) Alkali feed. An alkali feeder shall be provided for all ion exchange water softening plants to provide stable water unless the effluent water is shown to be non-corrosive. Other waters may also be corrosive and require pH adjustment. The chemical shall be adequately mixed and the point of application located such that any deposition in the piping is minimized. The piping shall be accessible for cleaning or replacement. Equipment for monitoring pH shall be provided. NR 811.58(5)(5) Carbon dioxide reduction by aeration. The carbon dioxide content of an aggressive water may be reduced by aeration. Aeration devices shall conform to s. NR 811.45. NR 811.58(6)(6) Other treatment. Other treatment for controlling corrosive waters by the use of sodium silicate and sodium bicarbonate may be used where necessary. Any proprietary compound shall receive the specific approval of the department before use. Chemical feeders shall comply with the requirements in subch. VI. NR 811.58(7)(7) Control. Laboratory equipment shall be provided for determining the effectiveness of stabilization treatment. NR 811.59NR 811.59 Taste and odor control. Waterworks which are designed and constructed to provide taste and odor control shall comply with any requirements provided for the following applicable methods: NR 811.59(1)(1) Chlorination. Chlorination is effective for the removal of some objectionable odors. Adequate concentration and contact time shall be provided to complete the chemical reactions involved. Excessive potential trihalomethane or other disinfection by-product production through this process shall be investigated by bench-scale testing prior to design. NR 811.59(2)(2) Chlorine dioxide. Chlorine dioxide may be used in the treatment of any taste or odor which is treatable by an oxidizing compound. Provision shall be made for proper storage and handling of sodium chlorite to eliminate any danger of explosion. NR 811.59(3)(a)(a) Powdered activated carbon may be added prior to coagulation to provide maximum contact time. Although facilities to allow the addition at several alternate points is recommended, in no case may carbon be added near the point of chlorine application.