NR 809.547(7)(g)1.1. If the water supplier for a public water system has demonstrated that the public water system is free of both lead-containing and copper-containing materials, as required by par. (a) and that its 90th percentile lead levels and 90th percentile copper levels meet the criteria of par. (b), the waiver remains in effect so long as the public water system continues to meet the waiver eligibility criteria of par. (e). The first round of tap water monitoring conducted pursuant to par. (d) shall be completed no later than 9 years after the last time the water supplier has monitored for lead and copper at the tap. Samples collected every nine years shall be collected no later than every ninth calendar year. NR 809.547(7)(g)2.2. If the public water system has met the materials criteria of par. (a) but has not met the monitoring criteria of par. (b), the water supplier shall conduct a round of monitoring for lead and copper at the tap demonstrating that the public water system meets the criteria of par. (b) to meet initial monitoring requirements. Thereafter, the waiver shall remain in effect as long as the public water system meets the continued eligibility criteria of par. (e). The first round of tap water monitoring conducted pursuant to par. (d) shall be completed no later than 9 years after the round of monitoring conducted pursuant to par. (b). NR 809.547 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; corrections in (4) (d) 5. and (6) (intro.) made under s. 13.92 (4) (b) 7., Stats., Register November 2010 No. 659; CR 15-049: am. (3), (4) (d) 2. Register March 2016 No. 723, eff. 4-1-16. NR 809.548NR 809.548 Monitoring requirements for water quality parameters. Water suppliers for all large systems, and for all small and medium-size systems that exceed the lead or copper action level, shall monitor water quality parameters in addition to lead and copper in accordance with this section. The requirements of this section are summarized in the table at the end of this section. NR 809.548(1)(a)1.1. Tap samples shall be representative of water quality throughout the distribution system taking into account the number of persons served, the different sources of water, the different treatment methods employed by the water supplier, and seasonal variability. Tap sampling under this section is not required to be conducted at taps targeted for lead and copper sampling under s. NR 809.547 (1). NR 809.548(1)(a)2.2. Samples collected at the entry points to the distribution system shall be from locations representative of each source after treatment. If a public water system draws water from more than one source and the sources are combined before distribution, the water supplier shall sample at an entry point to the distribution system during periods of normal operating conditions, i.e., when water is representative of all sources being used. NR 809.548(1)(b)1.1. The water supplier shall collect 2 tap samples for applicable water quality parameters during each monitoring period specified under subs. (2) to (5) from the following number of sites: NR 809.548(1)(b)2.2. Except as provided in sub. (3) (c), water suppliers shall collect 2 samples for each applicable water quality parameter at each entry point to the distribution system during each monitoring period specified in sub. (2). NR 809.548(2)(2) Initial sampling. Water suppliers of all large water systems shall measure the applicable water quality parameters as specified below at taps and at each entry point to the distribution system during each 6-month monitoring period specified in s. NR 809.547 (4) (a). Water suppliers of all small and medium-size systems shall measure the applicable water quality parameters at the locations specified below during each 6-month monitoring period specified in s. NR 809.547 (4) (a) during which the public water system exceeds the lead or copper action level. NR 809.548(2)(a)3.3. Orthophosphate, when an inhibitor containing a phosphate compound is used; NR 809.548(2)(b)(b) At each entry point to the distribution system: all of the applicable parameters listed in par. (a). NR 809.548(3)(3) Monitoring after installation of corrosion control. The water supplier of any large system which installs optimal corrosion control treatment pursuant to s. NR 809.542 (4) (d) shall measure the water quality parameters at the following locations and frequencies during each 6-month monitoring period specified in s. NR 809.547 (4) (b) 1. The water supplier of any small or medium-size system which installs optimal corrosion control treatment shall conduct such monitoring during each 6-month monitoring period specified in s. NR 809.547 (4) (b) 2. in which the public water system exceeds the lead or copper action level. NR 809.548(3)(a)3.3. Orthophosphate, when an inhibitor containing a phosphate compound is used; NR 809.548(3)(a)4.4. Silica, when an inhibitor containing a silicate compound is used; and NR 809.548(3)(a)5.5. Calcium, when calcium carbonate stabilization is used as part of corrosion control. NR 809.548(3)(b)(b) Except as provided in par. (c), at each entry point to the distribution system, one sample every 2 weeks for: NR 809.548(3)(b)2.2. When alkalinity is adjusted as part of optimal corrosion control, a reading of the dosage rate of the chemical used to adjust alkalinity and the alkalinity concentration; and NR 809.548(3)(b)3.3. When a corrosion inhibitor is used as part of optimal corrosion control, a reading of the dosage rate of the inhibitor used and the concentration of orthophosphate or silica, whichever is applicable. NR 809.548(3)(c)(c) The water supplier for a groundwater system can limit entry point sampling described in par. (b) to those entry points that are representative of water quality and treatment conditions throughout the public water system. If water from untreated groundwater sources mixes with water from treated groundwater sources, the water supplier shall monitor for water quality parameters both at representative entry points receiving treatment and representative entry points receiving no treatment. Prior to the start of any monitoring under this subsection, the water supplier shall provide to the department written information identifying the selected entry points and documentation, including information on seasonal variability, sufficient to demonstrate that the sites are representative of water quality and treatment conditions throughout the public water system. NR 809.548(4)(4) Monitoring after the department specifies water quality parameter values for optimal corrosion control. After the department specifies the values for applicable water quality control parameters reflecting optimal corrosion control treatment under s. NR 809.543 (6) and (7), water suppliers for all large systems shall measure the applicable water quality parameters in accordance with sub. (3) and determine compliance with the requirements of s. NR 809.543 (8) every six months with the first six-month period to begin on either January 1 or July 1, whichever comes first, after the department specifies the optimal values under s. NR 809.543 (6). Water suppliers for any small or medium-size systems shall conduct such monitoring during each six-month period specified in this paragraph in which the public water system exceeds the lead or copper action level. For any such small and medium-size system that is subject to a reduced monitoring frequency pursuant to s. NR 809.547 (4) (d) at the time of the action level exceedance, the start of the applicable six-month monitoring period under this paragraph shall coincide with the start of the applicable monitoring period under s. NR 809.547 (4) (d). Compliance with department designated optimal water quality parameter values shall be determined as specified under s. NR 809.543 (8). NR 809.548(5)(a)(a) Water suppliers for any public water system that maintains the range of values for the water quality parameters reflecting optimal corrosion control treatment during each of 2 consecutive 6-month monitoring periods under sub. (4) shall continue monitoring at the entry points to the distribution system as specified in sub. (3) (b). Water suppliers for such public water systems may collect 2 tap samples for applicable water quality parameters from the following reduced number of sites during each 6-month monitoring period. NR 809.548(5)(b)1.1. Water suppliers for any public water system that maintains the range of values for the water quality parameters reflecting optimal corrosion control treatment specified by the department under s. NR 809.543 (6) during 3 consecutive years of monitoring may reduce the frequency with which they collect the number of tap samples for applicable water quality parameters specified in par. (a) from every six months to annually. This sampling begins during the calendar year immediately following the end of the monitoring period in which the third consecutive year of six-month monitoring occurs. Water suppliers for any public water system that maintains the range of values for the water quality parameters reflecting optimal corrosion control treatment specified by the department under s. NR 809.543 (6) during 3 consecutive years of annual monitoring under this paragraph may reduce the frequency with which they collect the number of tap samples for applicable water quality parameters specified in par. (a) of this section from annually to every 3 years. This sampling begins no later than the third calendar year following the end of the monitoring period in which the third consecutive year of monitoring occurs. NR 809.548(5)(b)2.2. A water supplier for a public water system may reduce the frequency with which they collect tap samples for applicable water quality parameters specified in par. (a) to every 3 years if the public water system demonstrates during 2 consecutive monitoring periods that the public water system’s tap water lead level at the 90th percentile is less than or equal to the practical quantitation limit for lead specified in s. NR 809.541 (4) (a), that its tap water copper level at the 90th percentile is less than or equal to 0.65 mg/L for copper in s. NR 809.54 (3) (b), and that it also has maintained the range of values for the water quality parameters reflecting optimal corrosion control treatment specified by the department under s. NR 809.543 (6). Monitoring conducted every three years shall be done no later than every third calendar year. NR 809.548(5)(c)(c) Water suppliers for any public water system that maintains the range of values for the water quality parameters reflecting optimal corrosion control treatment specified by the department under s. NR 809.543 (6) during 3 consecutive years of annual monitoring may reduce the frequency with which they collect the number of tap samples for applicable water quality parameters specified in par. (a) from annually to every 3 years. NR 809.548(5)(d)(d) A water supplier that conducts sampling annually shall collect these samples evenly throughout the year so as to reflect seasonal variability. NR 809.548(5)(e)(e) Any water supplier that has a public water system subject to reduced monitoring frequency that fails to operate within the range of values for the water quality parameters specified by the department under s. NR 809.543 (6) for more than 9 days in any 6-month period specified in s. NR 809.543 (8) shall resume distribution system tap water sampling in accordance with the number and frequency requirements in sub. (4). A water supplier may resume annual monitoring for water quality parameters at the tap at the reduced number of sites specified in par. (a) after they have completed 2 subsequent consecutive 6-month rounds of monitoring that meet the criteria of that paragraph or may resume triennial monitoring for water quality parameters at the tap at the reduced number of sites after the water supplier demonstrates through subsequent rounds or monitoring that the public water system meets the criteria of either par. (b) 1. or 2., or both. Summary of Monitoring Requirements for Water Quality Parameters1
1 Table is for illustrative purposes; consult the text of this section for precise regulatory requirements.
2 Water supplier for small and medium-size systems have to monitor for water quality parameters only during monitoring periods in which the public water system exceeds the lead or copper action level.
3 Orthophosphate must be measured only when an inhibitor containing a phosphate compound is used. Silica must be measured only when an inhibitor containing silicate compound is used.
4 Calcium must be measured only when calcium carbonate stabilization is used as part of corrosion control.
5 Inhibitor dosage rates and inhibitor residual concentrations (orthophosphate or silica) must be measured only when an inhibitor is used.
6 Water supplier for groundwater systems may limit monitoring to representative locations throughout the public water system.
7 Water suppliers for public water systems may reduce frequency of monitoring for water quality parameters at the tap from every 6 months to annually if they have maintained the range of values for water quality parameters in the public water system reflecting optimal corrosion control during 3 consecutive years of monitoring.
8 Water suppliers for public water systems may further reduce the frequency of monitoring for water quality parameters at the tap from annually to once every 3 years if they have maintained the range of values for water quality parameters in the public water system reflecting optimal corrosion control during 3 consecutive years of annual monitoring. Water suppliers for public water systems may accelerate to triennial monitoring for water quality parameters at the tap if the public water system has maintained 90th percentile lead levels less than or equal to 0.005 mg/L, 90th percentile copper levels less than or equal to 0.65 mg/L, and the range of water quality parameters designated by the department under s. NR 809.543 (7) as representing optimal corrosion control during 2 consecutive 6-month monitoring periods. NR 809.548 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; corrections in (5) (b) 2. made under s. 13.92 (4) (b) 7., Stats., Register November 2010 No. 659; CR 15-049: am. (4) Register March 2016 No. 723, eff. 4-1-16. NR 809.549NR 809.549 Monitoring requirements for lead and copper in source water. NR 809.549(1)(1) Sample location, collection methods and number of samples. NR 809.549(1)(a)(a) The water supplier of a public water system that fails to meet the lead or copper action level on the basis of tap samples collected in accordance with s. NR 809.547 shall collect lead and copper source water samples in accordance with the requirements regarding sample location, number of samples and collection methods: NR 809.549(1)(a)1.1. The water suppliers for groundwater systems shall take a minimum of one sample at every entry point to the distribution system which is representative of each well after treatment. The water supplier shall take one sample at the same sampling location unless conditions make another sampling location more representative of each source or treatment plant. NR 809.549(1)(a)2.2. The water suppliers for surface water systems shall take a minimum of one sample at every entry point to the distribution system after any application of treatment or in the distribution system at a point which is representative of each source after treatment. The water supplier shall take each sample at the same sampling location unless conditions make another sampling location more representative of each source or treatment plant. For the purposes of this paragraph, surface water systems include public water systems with a combination of surface water and groundwater sources. NR 809.549(1)(a)3.3. If a public water system draws water from more than one source and the sources are combined before distribution, the water supplier shall sample at an entry point to the distribution system during periods of normal operating conditions, and when water is representative of all sources being used. NR 809.549(1)(a)4.4. The department may reduce the total number of samples which are to be analyzed by allowing the use of compositing. Compositing of samples shall be done by certified laboratory personnel. Composite samples from a maximum of 5 samples are allowed, provided that if the lead concentration in the composite sample is greater than or equal to 0.001 mg/L or the copper concentration is greater than or equal to 0.160 mg/ L, one of the following applies: NR 809.549(1)(a)4.a.a. A follow-up sample shall be taken and analyzed within 14 days at each sampling point included in the composite. NR 809.549(1)(a)4.b.b. If duplicates of or sufficient quantities from the original samples from each sampling point used in the composite are available, the water supplier may use these instead of resampling. NR 809.549(1)(b)(b) Where the results of sampling indicate an exceedance of maximum permissible source water levels established under s. NR 809.544 (2) (d), the department may require that one additional sample be collected as soon as possible after the initial sample was taken, but not to exceed 2 weeks, at the same sampling point. If a department-required confirmation sample is taken for lead or copper, then the results of the initial and confirmation sample shall be averaged in determining compliance with the department-specified maximum permissible levels. Any sample value below the detection limit shall be considered to be zero. Any value above the detection limit but below 5 ug/l, shall be considered as the measured value. NR 809.549(2)(2) Monitoring frequency after a public water system exceeds tap water action level. A water supplier for any public water system which exceeds the lead or copper action level at the tap shall collect one source water sample from each entry point to the distribution system no later than six months after the end of the monitoring period during which the lead or copper action level was exceeded. For monitoring periods that are annual or less frequent, the end of the monitoring period is September 30 of the calendar year in which the sampling occurs, or if the department has established an alternate monitoring period, the last day of that period. NR 809.549(3)(3) Monitoring frequency after installation of source water treatment. Any water supplier which installs source water treatment pursuant to s. NR 809.544 (1) (b) shall collect an additional source water sample from each entry point to the distribution system during 2 consecutive 6-month monitoring periods by the deadline specified in s. NR 809.544 (1) (d). NR 809.549(4)(4) Monitoring frequency after department specifies maximum permissible source water levels or determines that source water treatment is not needed. NR 809.549(4)(a)(a) A water supplier shall monitor at the frequency specified below in cases where the department specifies maximum permissible source water levels under s. NR 809.544 (2) (d) or determines that the water supplier is not required to install source water treatment under s. NR 809.544 (2) (b). NR 809.549(4)(a)1.1. A water supplier of a public water system using only groundwater shall collect samples once during the 3-year compliance period in effect when the applicable department determination under par. (a) is made. The water supplier shall collect samples once during each subsequent compliance period. Triennial samples shall be collected every third calendar year. NR 809.549(4)(a)2.2. A water supplier for a public water system using surface water, or a combination of surface and groundwater, shall collect samples once during each calendar year, the first annual monitoring period to begin during the year in which the applicable department determination is made under sub. (4) (a). NR 809.549(4)(b)(b) A water supplier is not required to conduct source water sampling for lead or copper, or both, if the public water system meets the action level for the specific contaminant in tap water samples during the entire source water sampling period applicable to the public water system under par. (a) 1. or 2. NR 809.549(5)(a)(a) A water supplier for a public water system using only groundwater may reduce the monitoring frequency for lead and copper in source water to once during each compliance cycle provided that the samples are collected no later than every ninth calendar year and if the public water system meets one of the following criteria: NR 809.549(5)(a)1.1. The water supplier for a public water system demonstrates that the finished drinking water entering the distribution system has been maintained below the maximum permissible lead and copper concentrations specified by the department in s. NR 809.544 (2) (d) during at least 3 consecutive compliance periods under sub. (4) (a). NR 809.549(5)(a)2.2. The department has determined that source water treatment is not needed and the water supplier for a public water system demonstrates that, during at least 3 consecutive compliance periods in which sampling was conducted under sub. (4) (a), the concentration of lead in source water was less than or equal to 0.005 mg/L and the concentration of copper in source water was less than or equal to 0.65 mg/L. NR 809.549(5)(b)(b) A water supplier for a public water system using surface water, or a combination of surface water and groundwater may reduce the monitoring frequency in sub. (4) (a) to once during each compliance cycle provided that the samples are collected no later than every ninth calendar year and if the public water system meets one of the following criteria: NR 809.549(5)(b)1.1. The water supplier for the public water system demonstrates that finished drinking water entering the distribution system has been maintained below the maximum permissible lead and copper concentrations specified by the department in s. NR 809.544 (2) (d) for at least 3 consecutive years. NR 809.549(5)(b)2.2. The department has determined that source water treatment is not needed and the water supplier for the public water system demonstrates that, during at least 3 consecutive years, the concentration of lead in source water was less than or equal to 0.005 mg/L and the concentration of copper in source water was less than or equal to 0.65 mg/L. NR 809.549(5)(c)(c) A public water system that uses a new source of water is not eligible for reduced monitoring for lead or copper, or both, until concentrations in samples collected from the new source during 3 consecutive monitoring periods are below the maximum permissible lead and copper concentrations specified by the department in s. NR 809.544 (1) (e). NR 809.549 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10. NR 809.55NR 809.55 Reporting requirements for lead and copper. All water suppliers shall report all of the following information to the department in accordance with this section: NR 809.55(1)(1) Reporting requirements for tap water monitoring for lead and copper and for water quality parameter monitoring. NR 809.55(1)(a)(a) All lead samples that are detected shall be quantified. Any sample below the method detection limit shall be calculated at zero for the purposes of determining compliance with s. NR 809.54 (3) (c). NR 809.55(1)(b)(b) All copper samples that are detected shall be quantified. Any sample below the method detection limit shall be calculated as zero for the purposes of determining compliance with s. NR 809.54 (3) (c). NR 809.55(1)(c)(c) Except as provided in subd. 8., a water supplier shall report the following information for all tap water samples specified in s. NR 809.547 and for all water quality parameter samples specified in s. NR 809.548 within the first 10 days following the end of each applicable monitoring period specified in ss. NR 809.547, 809.548 and 809.549, which is 6 months, annually, every 3 years, or every 9 years: NR 809.55(1)(c)1.1. The results of all tap samples for lead and copper including the location of each site and the criteria under s. NR 809.547 (1) (c), (d), (e), (f) or (g) under which the site was selected for the public water system’s sampling pool. For monitoring periods with a duration less than six months, the end of the monitoring period is the last date samples can be collected during that period as specified in ss. NR 809.547 and 809.548. NR 809.55(1)(c)3.3. At a time specified by the department, or if no specific time is designated by the department, then as early as possible prior to the addition of a new source or any long-term change in water treatment, a water supplier for a public water system deemed to have optimized corrosion control under s. NR 809.542 (2) (c), a public water system subject to reduced monitoring pursuant to s. NR 809.547 (4) (d), or a public water system subject to a monitoring waiver pursuant to s. NR 809.547 (7) shall submit written documentation to the department describing the change or addition. The department must review and approve the addition of a new source or long-term change in treatment to the public water system before it is implemented by the water supplier. Examples of long-term treatment changes include the addition of a new treatment process or modification of an existing treatment process. Examples of modifications include switching secondary disinfectants, switching coagulants, for example, alum to ferric chloride, and switching corrosion inhibitor products, for example, orthophosphate to blended phosphate. Long-term changes may include dose changes to existing chemicals if the water supplier is planning long-term changes to the public water system finished water pH or residual inhibitor concentration. Long-term treatment changes may not include chemical dose fluctuations associated with daily raw water quality changes. NR 809.55(1)(c)4.4. The 90th percentile lead and copper concentrations measured from among all lead and copper tap water samples collected during each monitoring period, calculated in accordance with s. NR 809.54 (3) (c), unless the department calculates the public water system’s 90th percentile lead and copper levels under sub. (8). NR 809.55(1)(c)5.5. With the exception of initial tap sampling conducted pursuant to s. NR 809.547 (4) (a), the water supplier shall designate any site which was not sampled during previous monitoring periods, and include an explanation of why sampling sites have changed; NR 809.55(1)(c)6.6. The results of all tap samples for pH and, where applicable, alkalinity, calcium, conductivity, temperature and orthophosphate or silica collected under s. NR 809.548 (2) to (5);
