Mercury   0.002
Methoxychlor   0.04
Monochlorobenzene   0.1
Nickel   0.1
Nitrate   10 (as Nitrogen)
Nitrite   1 (as Nitrogen)
Nitrate+Nitrite   10 (as Nitrogen)
Oxamyl   0.2
Picloram   0.5
Selenium   0.05
Simazine   0.004
Styrene   0.1
Toluene   1
1,2,4-Trichlorobenzene   0.07
1,1,1-Trichloroethane   0.2
1 Atrazine, total chlorinated residue includes atrazine and its metabolites, diaminoatrazine, diethylatrazine and deisopropylatrazine.
NR 809.07(4) (4)If a contaminant is not detected in a sample and if the limit of detection is higher than the MCLG, the MCLG shall be considered not to have been exceeded.
NR 809.07(5) (5)Notwithstanding any other provisions of this chapter, if a contaminant listed in sub. (2) is detected at a concentration above the MCLG but below the MCL for that contaminant, the following shall apply:
NR 809.07(5)(a) (a) The water supplier shall collect a confirmation sample to verify the presence of the contaminant, unless collected by the department.
NR 809.07(5)(b) (b) Based upon verified results and following a determination by the department on the need for further action as specified in par. (c), the water supplier shall provide public information to its customers indicating the analytical results achieved and the health effects of ingesting the substance at the concentration found.
NR 809.07(5)(c) (c) The department may require the water supplier to prepare and submit a report which does all of the following:
NR 809.07(5)(c)1. 1. Assesses the cause and significance of the problem.
NR 809.07(5)(c)2. 2. Analyzes the cost, effectiveness and feasibility of alternatives for treating the water or developing alternative water sources.
NR 809.07(5)(d) (d) If, based on the conclusions of the report if required under par. (c), the department determines that action is necessary to protect public health, it may require the water supplier to treat or replace the water source.
NR 809.07 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (1) Register March 2016 No. 723, eff. 4-1-16.
NR 809.09 NR 809.09 Applicability of primary maximum contaminant levels to water sources. Except as otherwise allowed in this chapter, no water source exceeding any primary maximum contaminant level in this chapter may be connected to a public water system unless blending or treatment is provided such that the primary maximum contaminant level is not exceeded upon entry to the distribution system.
NR 809.09 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.
NR 809.10 NR 809.10 Use of bottled water. Public water systems may not use bottled water to achieve compliance with an MCL. Bottled water may be used temporarily to avoid unreasonable risk to health.
NR 809.10 History History: CR 15-049: cr. Register March 2016 No. 723, eff. 4-1-16.
NR 809.11 NR 809.11 Inorganic chemical maximum contaminant levels and BATs.
NR 809.11(1)(1)Applicability. The following requirements apply to all of the maximum contaminant levels for inorganic contaminants:
NR 809.11(1)(a) (a) The maximum contaminant levels for nitrate and nitrite apply to both community water systems and non-community water systems, except as provided in sub. (3).
NR 809.11(1)(b) (b) The maximum contaminant level for fluoride only applies to community water systems.
NR 809.11(1)(c) (c) The maximum contaminant levels for antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, cyanide, mercury, nickel, selenium and thallium apply to community water systems and non-transient, non-community water systems.
NR 809.11(1)(d) (d) Compliance with maximum contaminant levels for inorganic chemicals is calculated under s. NR 809.117.
NR 809.11(2) (2)MCLs for inorganics. The following are the maximum contaminant levels for inorganic contaminants: - See PDF for table PDF
Antimony   0.006
Arsenic   0.010
Asbestos   7 Million fibers/Liter
  (longer than 10 um)
Barium   2
Beryllium   0.004
Cadmium   0.005
Chromium   0.1
Cyanide(as free Cyanide)0.2
Fluoride   4.0
Mercury   0.002
Nickel   0.1
Nitrate   10 (as Nitrogen)
Nitrite   1 (as Nitrogen)
Total Nitrate Nitrite   10 (as Nitrogen)
Selenium   0.05
Thallium   0.002
NR 809.11(3) (3)Operation with nitrates not exceeding 20 mg/l. At the discretion of the department, nitrate as nitrogen levels not to exceed 20 mg/l may be allowed in a non-community water system if the water supplier demonstrates all of the following to the satisfaction of the department:
NR 809.11(3)(a) (a) The water will not be available to children under 6 months of age or any female who is or may become pregnant.
NR 809.11(3)(b) (b) The water supplier meets the public notification requirements under s. NR 809.958, including continuous posting of the fact that nitrate as nitrogen levels exceed 10 mg/l and the potential health effects of exposure.
NR 809.11(3)(c) (c) Local and state public health authorities will be notified annually of nitrate as nitrogen levels that exceed 10 mg/l.
NR 809.11(3)(d) (d) A supply of bacteriologically safe drinking water, containing less than 10 mg/l nitrate as nitrogen, is provided for infants less than 6 months of age and any female who is or may become pregnant.
NR 809.11(3)(e) (e) No adverse health effects will result.
NR 809.11(4) (4)Best available treatment. The best available treatment technologies for inorganic contaminants are as follows:
NR 809.11(4)(a) (a) The best available technologies or BATs for achieving compliance with the maximum contaminant levels for the inorganic contaminants listed in sub. (2), except for fluoride, are as follows: - See PDF for table PDF
NR 809.11 Note Key to BATs in Table:
NR 809.11 Note 1 = Activated Alumina
NR 809.11 Note 2 = Coagulation/Filtration (not BAT for public water systems < 500 service connections)
NR 809.11 Note 3 = Direct and Diatomite Filtration
NR 809.11 Note 4 = Granular Activated Carbon
NR 809.11 Note 5 = Ion Exchange
NR 809.11 Note 6 = Lime Softening (not BAT for public water systems < 500 service connections)
NR 809.11 Note 7 = Reverse Osmosis
NR 809.11 Note 8 = Corrosion Control
NR 809.11 Note 9 = Electrodialysis
NR 809.11 Note 10 = Oxidation (Chlorine)
NR 809.11 Note 11 = Ultraviolet
NR 809.11 Note 12 = Oxidation/Filtration
NR 809.11 Note 13 = Alkaline Chlorination (pH 8.5)
NR 809.11(4)(b) (b) A water supplier may use an alternative treatment not listed in par. (a) if it is demonstrated to the department, using pilot studies or other means, that the alternative treatment is sufficient to achieve compliance with the MCLs in sub. (2).
NR 809.11(5) (5)Small water system compliance technologies for Arsenic.
NR 809.11(5)(a)(a) The EPA identifies the following table as the affordable technology, treatment technique, or other means available to public water systems serving 10,000 persons or fewer for achieving compliance with the maximum contaminant level for arsenic: - See PDF for table PDF
NR 809.11(5)(b) (b) The department may allow Point of Use (POU) treatment only if the department determines that treatment prior to entry to the distribution system is not feasible.
NR 809.11 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (2), (3) (a), (d), (4) (a) Register March 2016 No. 723, eff. 4-1-16.
NR 809.113 NR 809.113Sample collection and analytical requirements for inorganic contaminants.
NR 809.113(1)(1)analytical methods. Analyses conducted to determine compliance with s. NR 809.11 shall be made in accordance with methods listed in Table A. - See PDF for table PDF
Copies of the documents may be obtained from the sources listed below. Information regarding obtaining these documents can be obtained from the Safe Drinking Water Hotline at 800–426–4791, or go to:
1   “Methods for Chemical Analysis of Water and Wastes," EPA/600/4–79/020, March 1983. Available at NTIS, PB84–128677.
2   “Methods for the Determination of Metals in Environmental Samples—Supplement I," EPA/600/R–94/111, May 1994. Available at NTIS, PB95–125472.
3   Annual Book of ASTM Standards, 1994, 1996, 1999, or 2003, Vols. 11.01 and 11.02, ASTM International; any year containing the cited version of the method may be used. The previous versions of D1688–95A, D1688–95C (copper), D3559–95D (lead), D1293–95 (pH), D1125–91A (conductivity) and D859–94 (silica) are also approved. These previous versions D1688–90A, C; D3559–90D, D1293–84, D1125–91A and D859–88, respectively are located in the Annual Book of ASTM Standards, 1994, Vol. 11.01. Copies may be obtained from ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428.
4   Standard Methods for the Examination of Water and Wastewater, 18th edition (1992), 19th edition (1995), 20th edition (1998), 21st edition (2005), or 22nd edition (2012). American Public Health Association, 1015 Fifteenth Street, NW., Washington, DC 20005. The cited methods published in any of these three editions may be used, except that the versions of 3111 B, 3111 D, 3113 B and 3114 B in the 20th edition may not be used.
5 Method I–2601–90, Methods for Analysis by the U.S. Geological Survey National Water Quality Laboratory— Determination of Inorganic and Organic Constituents in Water and Fluvial Sediment, Open File Report 93–125, 1993; For Methods I–1030–85; I–1601–85; I–1700– 85; I–2598–85; I–2700–85; and I–3300–85 See Techniques of Water Resources Investigation of the U.S. Geological Survey, Book 5, Chapter A–1, 3rd edition., 1989; Available from Information Services, U.S. Geological Survey, Federal Center, Box 25286, Denver, CO 80225–0425.
6 “Methods for the Determination of Inorganic Substances in Environmental Samples," EPA/600/R–93/100, August 1993. Available at NTIS, PB94–120821.
7 The procedure shall be done in accordance with the Technical Bulletin 601 " Standard Method of Test for Nitrate in Drinking Water," July 1994, PN 221890–001, Analytical Technology, Inc. Copies may be obtained from ATI Orion, 529 Main Street, Boston, MA 02129.
Published under s. 35.93, Stats. Updated on the first day of each month. Entire code is always current. The Register date on each page is the date the chapter was last published.