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)(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.
NR 811.40(1)(j)
(j) Overflow pipes, if provided, shall be turned downward, provided with a 24-mesh corrosion resistant screen, have a free air break discharge, and be located in a conspicuous location.
NR 811.40(1)(k)
(k) If subsurface locations for solution or storage tanks are approved by the department, the tanks shall be free from sources of possible contamination and located to assure positive drainage for groundwater, accumulated water, chemical spills, and overflows.
NR 811.40(1)(L)
(L) Chemicals shall be stored in accordance with the following requirements:
NR 811.40(1)(L)1.
1. Each chemical shall be provided with its own secondary leakage containment.
NR 811.40(1)(L)2.
2. Each of the following chemicals shall be stored in a separate room with no other chemicals:
NR 811.40(1)(m)
(m) All buried chemical solution lines and gas lines shall be installed within protective conduit piping. Each chemical solution line shall be placed in its own protective conduit piping.
NR 811.40 Note
Note: When the chemical feed equipment will not be installed near the point of chemical application it is recommended that chemical solution piping be installed within protective conduit from the chemical feed equipment to the point of chemical application.
NR 811.40(1)(n)
(n) Gases from feeders, storage, and equipment exhausts shall be conveyed to the exterior of the building above grade and remote from air intakes to reduce the health and safety risk to operators and reduce corrosion of equipment and facilities from chemical vapors. Chemical vapor ventilation systems shall meet the following requirements as applicable:
NR 811.40(1)(n)1.
1. Fluoride and ammonia liquid storage tanks shall be vented to the exterior of the building but not through vents in common with day tanks.
NR 811.40(1)(n)2.
2. Chemical tank vents, when provided, shall be vented to the exterior of the building and terminate downward facing with a 24-mesh corrosion resistant screen. The tank vent shall terminate as high as practical, but a minimum of 24 inches above surrounding grade.
NR 811.40(1)(o)
(o) Permanent signs identifying the chemical for each fill tube shall be posted at chemical offloading areas. Permanent signs identifying the tank contents shall be posted adjacent to or on chemical storage tanks.
NR 811.40(1)(p)
(p) Compliance with local, state, and federal safety codes, including department of safety and professional services and OSHA codes, for other applicable chemical safety and handling requirements is required.
NR 811.40(2)
(2)
Handling facilities. Handling facilities shall meet the following requirements:
NR 811.40(2)(a)
(a) Equipment shall be provided for measuring quantities of chemicals used to prepare feed solutions.
NR 811.40(2)(b)
(b) Piping for chemicals shall be compatible with the chemical being conveyed.
NR 811.40(2)(c)
(c) The following equipment shall be provided for each installation where chemicals are handled:
NR 811.40(2)(c)1.
1. Where the eyes or body of any person may be exposed to injurious corrosive materials, suitable facilities for quick drenching or flushing of the eyes and body shall be provided as required in s.
SPS 332.15.
NR 811.40(2)(c)2.
2. Rubber gloves, protective clothing, and safety goggles that form a tight seal with the face shall be provided for each operator who prepares chemical solutions.
NR 811.40(2)(c)3.
3. A dust respirator of the prescribed type shall be provided for handling dry chemicals if required in the respective material safety data sheet or s.
SPS 332.15.
NR 811.40(2)(d)
(d) Provision shall be made for the transfer of dry chemicals from shipping containers to storage bins or hoppers in such a way as to minimize the quantity of dust generated. Control shall be provided by use of one of the following:
NR 811.40(2)(d)2.
2. Facilities for emptying shipping containers in special containers.
NR 811.40(2)(d)3.
3. Exhaust fans and dust filters which place the hoppers or bins under negative pressure.
NR 811.40(2)(e)
(e) Carts, elevators, or other appropriate means shall be provided for lifting chemical containers to minimize lifting by operators.
NR 811.40(2)(f)
(f) Electrical equipment shall be used which will prevent explosions, particularly when using sodium chlorite and activated carbon. Equipment shall comply with ch.
SPS 316.
NR 811.40(2)(g)
(g) Procedures for disposing of empty bags, drums, carboys, or barrels shall minimize exposure to dusts or chemicals.
NR 811.40(2)(h)
(h) Acids shall be kept in closed, acid-resistant shipping containers, or storage units. Transfer from shipping containers to solution or day tanks shall be through acid resistant hose or pipe by means of a transfer pump.
NR 811.40(3)
(3)
Chemicals. All chemicals used to treat or produce potable water shall meet the following requirements:
NR 811.40(3)(a)
(a) Shipping containers shall be fully labeled to include chemical name, purity, applicable NSF/ANSI standard approval in conformance with par.
(b), concentration and supplier name and address.
NR 811.40 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10; correction in (1) (p), (2) (c) 1., 3., (f) made under s.
13.92 (4) (b) 6.,
7., Stats.,
Register December 2011 No. 672;
CR 22-074: cr. (1) (cm), am. (1) (d), (g), (j), r. and recr. (1) (L), renum. (1) (n) to (1) (n) (intro.) and am., cr. (1) (n) 1., 2., Register January 2024 No. 817, eff. 2-1-24. NR 811.41
NR 811.41 General treatment design. The design of treatment processes and devices shall depend on evaluation of the nature and quality of the particular water to be treated and the desired quality of the finished water. Treatment shall be provided by each supplier of water if necessary in order to ensure that the finished water supplied to consumers meets the primary maximum contaminant levels contained in ch.
NR 809 and is not objectionable to an appreciable number of consumers. The requirements of specific treatment processes are provided in ss.
NR 811.42 to
811.60.
NR 811.41 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10.
NR 811.42
NR 811.42 Treatment of water from surface water sources. Treatment of water from surface water sources shall meet the following requirements:
NR 811.42(1)
(1)
General requirements. All public water supply systems drawing water from lakes, rivers, streams, or other surface water sources shall, after the water is drawn, treat the water as provided in this chapter. In general and at a minimum, this treatment shall include coagulation, sedimentation, and filtration plus disinfection or membrane filtration plus disinfection. Filtration is required in all cases. Total plant removal and inactivation shall provide a minimum 99.9 percent (3-log) inactivation of
Cryptosporidium and
Giardia Lamblia plus 99.99 percent (4-log) inactivation of viruses.
NR 811.42(2)
(2)
Treatment requirements. The following treatment requirements shall be met:
NR 811.42(2)(a)
(a) Conventional plants consisting of coagulation, sedimentation, and filtration that meet the turbidity requirements in s.
NR 810.29 (1) are granted the following removal credits: 99.7 percent (2.5-log)
Giardia Lamblia, 99.9 percent (3.0-log)
Cryptosporidium and 99 percent (2-log) virus. The remaining 68 percent (0.5-log)
Giardia Lamblia inactivation and 99 percent (2.0-log) virus inactivation shall be provided by CT disinfection. For conventional plants, a minimum of one-half of the required CT shall be provided after filtration.
NR 811.42(2)(b)
(b) Log removal credit for membrane filtration shall be site specific as approved by the department.
NR 811.42(2)(d)
(d) The department may approve any request for a deviation from required treatment methods based on data which shows that the requirements of this chapter are unnecessary in the specific case.
NR 811.42(3)
(3)
Redundancy. All critical treatment components shall be provided with redundancy.
NR 811.42(4)
(4)
CT values. CT values for the inactivation of
Giardia Lamblia,
Cryptosporidium, and viruses can be found in ss.
NR 810.47 to
810.62.
NR 811.42(5)
(5)
Chlorine residual requirements. The free chlorine concentration in the water entering the distribution system shall be at least 0.2 mg/1 at the entry point to the distribution system and detectable throughout the distribution system or the total combined chlorine concentration shall be at least 1.0 mg/l at the entry point to the distribution system and detectable throughout the distribution system. Continuous chlorine residual monitoring of the water entering the distribution system shall be provided as required in ss.
NR 809.74 (2) and
810.38 (2) (c).
NR 811.42 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10.
NR 811.43
NR 811.43 Treatment of water from groundwater sources. Treatment of water from groundwater sources shall meet the following requirements:
NR 811.43(1)
(1)
Disinfection capability required. All municipal water systems constructed or modified after December 1, 2010, shall have equipment and the necessary appurtenances that can continuously disinfect the water. The department may require the installation of disinfection equipment at existing other-than-municipal water systems if necessary to ensure a safe water supply.
NR 811.43(2)
(2)
Disinfectant residual requirements. Disinfection of water drawn from groundwater sources is to supplement and not replace proper well location, construction, and source protection. When disinfection of water drawn from a groundwater source is required to maintain bacteriologically safe water, the residual maintained in the distribution system and the residual monitoring is the same as that required for surface water in s.
NR 811.42 (5).
NR 811.43(3)
(3)
Disinfection requirements for wells. Specific disinfection requirements for wells are provided in subch.
II. Any additional disinfection requirements for wells will be developed by the department if necessary on a case by case basis.
NR 811.43(4)
(4)
Disinfection of groundwater exposed to the atmosphere as part of a treatment process. Disinfection of water drawn from groundwater sources is required at facilities that expose the water to the atmosphere, such as open basins, open filters, air stripping towers, or gravity aerators.
NR 811.43(5)
(5)
Required actions for wells with non-complying water quality. One of the following actions shall be taken after consulting with the department if untreated water drawn from a groundwater source exceeds one or more of the primary maximum contaminant levels in ch.
NR 809 or a department health advisory:
NR 811.43(5)(a)
(a) The well shall be removed from service and permanently abandoned.
NR 811.43(5)(b)
(b) The well shall be removed from service and either reconstructed or provided with permanent treatment to provide complying water quality. Wells may temporarily continue in service without reconstruction or providing permanent treatment only as approved by the department. Department approval is required prior to reconstructing the well or providing water treatment. Under emergency conditions, the department may allow temporary use of a well from which bacteriologically contaminated groundwater is drawn if disinfection adequate to ensure safe water is provided. In such cases, disinfection measures meeting the requirements of sub.
(3) shall be provided. A continuous boil water notice may be required by the department during all or part of this interim period if deemed necessary by the department to protect public health.
NR 811.43(6)
(6)
Groundwater under the direct influence of surface water. The department may allow the use of water drawn from a groundwater source that has been determined by the department to be under the direct influence of surface water provided that treatment facilities meeting the requirements of subch.
II of ch. NR 810 are provided as approved by the department. The total plant removal and inactivation shall provide a minimum 3-log inactivation of
Cryptosporidium and
Giardia Lamblia plus 4-log inactivation of viruses. The disinfectant residual maintained in the distribution system and residual monitoring shall be the same as required for treatment of water drawn from a surface water source in s.
NR 811.42 (5). The department may approve modified treatment requirements for other-than-municipal public water systems if surface water treatment is impractical and if sufficient treatment can be provided. The supplier of water shall contact the department to determine what modified treatment will be approved.
NR 811.43(7)
(7)
Redundancy. All critical treatment components shall be provided with redundancy.
NR 811.43(8)
(8)
CT values. CT values for the inactivation of
Giardia Lamblia,
Cryptosporidium, and viruses can be found in ss.
NR 810.47 to
810.62.
NR 811.43(9)
(9)
Treatment for nitrate. If the source water quality exceeds the nitrate maximum contaminant level set under s.
NR 809.11 and treatment, blending, or other department-approved methods are provided to reduce the entry point nitrate concentration beneath the maximum contaminant level, a continuous nitrate analyzer shall be provided at the entry point. The continuous nitrate analyzer shall be programmed to include shut off controls or alarms if the nitrate concentration at the entry point exceeds the maximum contaminant level.
NR 811.43 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 22-074: am. (1), (4), cr. (9) Register January 2024 No. 817, eff. 2-1-24. NR 811.44
NR 811.44 Pilot testing. Pilot testing is required to establish effective treatment and operation requirements for new treatment methods, if revisions are proposed to existing treatment methods, if the water quality poses significant treatment issues, and if design parameters need to be determined for the first time or for the specific site conditions. The department may waive the pilot testing requirement if information on other locations where the proposed treatment methods using similar water quality are already in place and operating successfully is available or if other justification necessary to support the proposed treatment processes is submitted to the department. Pilot testing shall address the following requirements:
NR 811.44(1)
(1) Plans, specifications, and an engineering report detailing the proposed pilot plant design, operation, sampling, lab analyses, and any waste disposal shall be submitted to the department and the written approval of the department shall be obtained prior to constructing or operating the pilot plant. At minimum, the pilot plant proposal shall address the following issues, where they apply:
NR 811.44(1)(a)
(a) Pilot plant treatment design including all operating parameters.
NR 811.44(1)(b)
(b) Length of pilot plant operation. The pilot plant shall operate long enough to establish the treatment effectiveness, media run lengths, wastewater volumes and characteristics, and any other necessary operating parameters. The pilot plant shall operate through a minimum of 2 treatment cycles or as determined by the department.
NR 811.44(1)(c)
(c) Chemicals and chemical feed equipment to be used along with chemical addition rates.
NR 811.44(1)(f)
(f) Backflow or back-siphon protection for any water system facilities that the pilot plant may be connected to.
NR 811.44(1)(h)
(h) Justification for pilot plant design and operation that does not meet the requirements of the applicable sections of subch.
VII.
NR 811.44(2)
(2) A report summarizing the results of the pilot plant testing and making recommendations for any full scale water system improvements shall be submitted to the department for review and comment by the owner or the owner's representative prior to or along with the submittal of plans and specifications for any permanent installations.
NR 811.44 Note
Note: The department recommends the submittal of pilot plant results reports prior to submittal of final plans and specifications for treatment vessels.
NR 811.44 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 22-074: cr. (1) (h) Register January 2024 No. 817, eff. 2-1-24. NR 811.45
NR 811.45 Aeration. Aeration treatment devices described in this section may be used for oxidation, separation of gases, or for taste and odor control. Air stripping towers shall meet the requirements of s.
NR 811.53 (2), which can be used for the removal or reduction of some volatile organic compounds. The following requirements shall be met:
NR 811.45(1)
(1)
Natural draft aeration. The design for natural draft aeration shall provide that:
NR 811.45(1)(b)
(b) Water is discharged through a series of 3 or more trays with separation of trays not less than 6 inches.
NR 811.45(1)(c)
(c) Trays are loaded at a rate of one to 5 gallons per minute for each square foot of total tray area.
NR 811.45(1)(d)
(d) Trays have slotted, heavy woven wire mesh with 0.5-inch openings or perforated bottoms.
NR 811.45(1)(e)
(e) Perforations are 3/16 to 1/2 inches in diameter, spaced one to 3 inches on center, when perforations are used.
