NR 811.39(6)(f)(f) Radar and sonic level sensors that are programmed to display in pounds of chemical and that are accurate enough to measure increments of 0.5 percent of load may be used to determine chemical use.

NR 811.39(7)(a)(a) Be as short as possible in length of run, of durable, corrosion resistant material, easily accessible throughout the entire length, protected against freezing, and readily cleanable.

NR 811.39(7)(b)(b) Slope upward from chemical source to feeder when conveying gases.

NR 811.39(7)(c)(c) Introduce corrosive chemicals in a manner to minimize potential for corrosion.

NR 811.39(7)(d)(d) Be designed consistent with scale-forming or solids-depositing properties of the water, chemical, solution, or mixture conveyed.

NR 811.39(7)(e)(e) Not carry chlorine gas under pressure beyond the chlorine feeder room.

NR 811.39(7)(f)(f) Include injection taps constructed of metal or SCH 80 PVC components and check valves. Removable injection quills shall be provided when application is into a pipe of adequate diameter. Injection quills installed in a horizontal section of pipe shall be installed up into the bottom half of the pipe.

NR 811.39(7)(g)(g) Be color coded in accordance with s. NR 811.28 (6).

NR 811.39(8)(8) Service and carrier water supply. Water used for dissolving dry chemicals, diluting liquid chemicals, operating chemical feeders or as carrier water to deliver chemicals to injection locations shall be from a safe, approved source with appropriate backflow prevention provided. The department may grant an exception in cases where the finished water quality will not be affected by addition of the chemical mixed with untreated water.

NR 811.39 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 22-074: am. (2) (e) (intro.), r. (2) (e) 2., renum. (2) (e) 3. to (2) (e) 3. (intro.) and am., cr. (2) (e) 3. a. to e., am. (2) (f) 1., (3) (d), r. and recr. (6) (intro.), am. (6) (a) to (d), cr. (6) (e), (f), am. (7) (f) Register January 2024 No. 187, eff. 2-1-24.

NR 811.40NR 811.40 Storage and handling. Specific requirements regarding storage and handling are provided in the sections covering the particular chemical. Storage and handling installations shall meet the following general requirements:

NR 811.40(1)(a)(a) Space shall be provided for at least 30 days of chemical supply, convenient and efficient handling, dry storage conditions, and a minimum of 1.5 truck loads storage volume where purchase is by truck load.

NR 811.40(1)(b)(b) Covered or unopened shipping containers shall be provided for storage unless the chemical is transferred into an approved covered storage unit. Solution tanks shall have overlapping or threaded covers that provide sanitary protection for the chemical being stored. Large tanks shall be covered and those with top access openings shall have either threaded covers or the openings shall be curbed and fitted with overlapping covers. Grommets, pipe seals, or other sanitary means shall be provided to create a sanitary seal where tubes, hoses, and pipes pass through the walls or covers of chemical storage tanks.

NR 811.40(1)(c)(c) Solution storage or day tanks supplying chemical feeders directly shall have at a minimum sufficient capacity for one day of operation. If the chemical solution is prepared from a powder or slurry, 2 solution tanks shall be required if necessary to assure continuity of feed.

NR 811.40(1)(cm)(cm) Graduated lines may not be used to determine daily chemical usage when the daily use is less than 5 percent of the tank capacity.

NR 811.40(1)(d)(d) Solution storage or day tanks supplying feeders directly shall have a maximum capacity such that daily chemical solution usage is a minimum of 5 percent of the tank capacity. The department may approve chemical container storage volumes that will allow daily chemical solution usage less than 5 percent of the tank capacity if supporting information is provided to the department and the chemical storage container is placed on a scale, or another department approved method is installed, to accurately determine daily chemical usage. Graduated lines shall not be used to determine daily chemical usage in cases when the daily use is less than 5 percent of the tank capacity. The maximum storage volume shall not exceed 45 days for sodium hypochlorite and 60 days for all other chemicals.

NR 811.40(1)(e)(e) Storage facilities shall be constructed of, or lined with, materials compatible with the chemical being handled.

NR 811.40(1)(f)(f) Mixing equipment shall be provided where necessary to assure a uniform chemical solution strength. Continuous mixing shall be provided to maintain slurries in suspension.

NR 811.40(1)(g)(g) Means shall be provided to accurately determine the amount of chemical applied in accordance with s. NR 811.39 (6).

NR 811.40(1)(h)(h) For non-bulk tanks, suction lines shall extend into the tank through the tank cover. Chemical feed pumps shall be installed at a height above the maximum liquid level in the chemical storage tank. Flooded suctions, for bulk tanks and if necessary to prevent loss of prime, may be approved by the department on a case-by-case basis.

NR 811.40(1)(i)(i) Adequate means of draining tanks shall be provided, but there may be no direct connection between any drain piping and a sanitary sewer. Chemicals shall not be discharged directly to a storm sewer. Drain piping shall terminate at least 2 pipe diameters, but not less than 3 inches, above the overflow rim of a receiving sump, conduit or waste receptacle.