Chapter NR 809

NR 809.53(1)(c)4. 4. If the average of the initial monitoring results for a sampling point is above the MCL, the water supplier for a community water system shall collect and analyze quarterly samples at that sampling point until the water supplier has results from 4 consecutive quarters that are at or below the MCL, unless the water supplier enters into another schedule as part of a formal compliance agreement with the department.

NR 809.53(1)(d) (d) Reduced monitoring. Upon completion of initial monitoring the department may allow monitoring once every 3 years, once every 6 years, or once every 9 years, for each sampling point based on the following criteria:

NR 809.53(1)(d)1. 1. If the average of the initial monitoring results for each contaminant, i.e., gross alpha particle activity, uranium, radium-226 or radium-228, is below the detection limit specified in s. NR 809.52 (2), Table O, the water supplier for a community water system shall collect and analyze for that contaminant using at least one sample at that sampling point every 9 years.

NR 809.53(1)(d)2. 2. For gross alpha particle activity and uranium, if the average of the initial monitoring results for each contaminant is at or above the detection limit but at or below one-half the MCL, the water supplier for a community water system shall collect and analyze for that contaminant using at least one sample at that sampling point every 6 years. For combined radium-226 and radium-228, the analytical results shall be combined. If the average of the combined initial monitoring results for radium-226 and radium-228 is at or above the detection limit but at or below one-half the MCL, the water supplier for a community water system shall collect and analyze for that contaminant using at least one sample at that sampling point every 6 years.

NR 809.53(1)(d)3. 3. For gross alpha particle activity and uranium, if the average of the initial monitoring results for each contaminant is above one-half the MCL but at or below the MCL, the water supplier for a community water system shall collect and analyze at least one sample at that sampling point every 3 years. For combined radium-226 and radium-228, the analytical results shall be combined. If the average of the combined initial monitoring results for radium-226 and radium-228 is above one-half the MCL, but at or below the MCL, the water supplier for a community water system shall collect and analyze at least one sample at that sampling point every 3 years.

NR 809.53(1)(d)4. 4. Results of samples collected during a reduced monitoring period shall be used to determine the monitoring frequency for subsequent monitoring periods.

NR 809.53(1)(d)5. 5. If a community water system has a monitoring result that exceeds the MCL while on reduced monitoring, the water supplier for a community water system shall collect and analyze quarterly samples at that sampling point until the community water system has results from 4 consecutive quarters that are below the MCL, unless the water supplier for a community water system enters into another schedule as part of a formal compliance agreement with the department.

NR 809.53(1)(e) (e) Compositing. To fulfill quarterly monitoring requirements for gross alpha particle activity, radium-226, radium-228 or uranium, a water supplier for a community water system may composite up to 4 consecutive quarterly samples from a single entry point if analysis is done within a year of the first sample. The department will treat analytical results from the composited results as the average analytical result to determine compliance with the MCLs and the future monitoring frequency. If the analytical result from the composited sample is greater than one-half the MCL, the department may direct the water supplier to take additional quarterly samples before allowing the water supplier to sample under a reduced monitoring schedule.

NR 809.53(1)(f) (f) Gross alpha particle activity measurement substitutions. A gross alpha particle activity measurement may be substituted for the required radium-226 measurement provided that the measured gross alpha particle activity does not exceed 5 pCi/l. A gross alpha particle activity measurement may be substituted for the required uranium measurement provided that the measured gross alpha particle activity does not exceed 15 pCi/l. The gross alpha measurement shall have a confidence interval of 95% confidence level, 1.65 ó where ó is the standard deviation of the net counting rate of the sample for radium-226 and uranium. When a water supplier for a community water system uses a gross alpha particle activity measurement in lieu of a measurement for radium-226 or uranium, or both, the gross alpha particle activity analytical result shall be used to determine the future monitoring frequency for radium-226 or uranium, or both. If the gross alpha particle activity result is less than detection, one-half the detection limit shall be used to determine compliance and the future monitoring frequency.

NR 809.53(2) (2) Monitoring requirements for beta particle and photon radioactivity. To determine compliance with the maximum contaminant levels in s. NR 809.51 for beta particle and photon radioactivity, a water supplier for a community water system shall monitor at a frequency as follows:

NR 809.53(2)(a) (a) Community water systems designated by the department as vulnerable, shall be sampled for beta particle and photon radioactivity. Water suppliers for community water systems shall collect quarterly samples for beta emitters and annual samples for tritium and strontium-90 at each entry point to the distribution system, no later than one quarter after being notified by the department. Community water systems already designated by the department shall continue to be sampled until the department reviews and either reaffirms or removes the designation.

NR 809.53(2)(a)1. 1. If the gross beta particle activity minus the naturally occurring potassium-40 beta particle activity at an entry point has a running annual average, computed quarterly, less than or equal to 50 pCi/l, the department may reduce the frequency of monitoring at that entry point to once every 3 years. Water suppliers for community water systems shall collect all samples required in this subsection during the reduced monitoring period.

NR 809.53(2)(a)2. 2. For community water systems in the vicinity of a nuclear facility, the department may allow the water supplier for the community water system to utilize environmental surveillance data collected by the nuclear facility in lieu of monitoring at the community water system’s entry points, if the department determines that the data is applicable to a particular community water system. If there is a release from a nuclear facility, water suppliers for community water systems which are using surveillance data shall begin monitoring at the community water system’s entry points in accordance with this subsection.

NR 809.53(2)(a)3. 3. At the discretion of the department, water suppliers for the community water systems utilizing only groundwater may be required to monitor for manmade radioactivity.

NR 809.53(2)(b) (b) Water suppliers for community water systems designated by the department as utilizing waters contaminated by effluents from nuclear facilities shall sample for beta particle and photon radioactivity. Water suppliers shall collect quarterly samples for beta emitters and iodine-131 and annual samples for tritium and strontium-90 at each entry point to the distribution system, beginning no later than one quarter after being notified by the department. Water suppliers for community water systems already designated by the department as community water systems using water contaminated by effluents from nuclear facilities shall continue to sample until the department reviews and either reaffirms or removes the designation.

NR 809.53(2)(b)1. 1. Quarterly monitoring for gross beta particle activity shall be based on the analysis of monthly samples or the analysis of a composite of 3 monthly samples.

NR 809.53 Note Note: Quarterly monitoring for gross beta particle activity based on the analysis of monthly samples is recommended.

NR 809.53(2)(b)2. 2. For iodine-131, a composite of 5 consecutive daily samples shall be analyzed once each quarter. As ordered by the department, more frequent monitoring shall be conducted when iodine-131 is identified in the finished water.

NR 809.53(2)(b)3. 3. Annual monitoring for strontium-90 and tritium shall be conducted by means of the analysis of a composite of 4 consecutive quarterly samples or analysis of 4 quarterly samples.

NR 809.53 Note Note: Annual monitoring for strontium-90 and tritium by means of the analysis of a composite of 4 consecutive quarterly samples is recommended.

NR 809.53(2)(b)4. 4. If the gross beta particle activity minus the naturally occurring potassium-40 beta particle activity at a sampling point has a running annual average, computed quarterly, less than or equal to 15 pCi/l, the department may reduce the frequency of monitoring at that sampling point to once every 3 years. Water suppliers for community water systems shall collect all samples required in this paragraph during the reduced monitoring period.

NR 809.53(2)(b)5. 5. For community water systems in the vicinity of a nuclear facility, the department may allow the water supplier for community water system to utilize environmental surveillance data collected by the nuclear facility in lieu of monitoring at the community water system’s entry points, if the department determines that the data is applicable to a particular community water system. If there is a release from a nuclear facility, water suppliers for community water systems which are using surveillance data shall begin monitoring at the community water system’s entry points in accordance with this paragraph.

NR 809.53(2)(c) (c) Water suppliers for community water systems designated by the department to monitor for beta particle and photon radioactivity may not apply to the department for a waiver from the monitoring frequencies specified in either par. (a) or (b).

NR 809.53(2)(d) (d) Water suppliers for community water systems may analyze for naturally occurring potassium-40 beta particle activity from the same or equivalent sample used for the gross beta particle activity analysis. Water suppliers for community water systems may subtract the potassium-40 beta particle activity value from the total gross beta particle activity value to determine if 50 pCi/l is exceeded. The potassium-40 beta particle activity shall be calculated by multiplying elemental potassium concentrations, in mg/l, by a factor of 0.82.

NR 809.53(2)(e) (e) If the gross beta particle activity minus the naturally occurring potassium-40 beta particle activity exceeds 50 pCi/l, an analysis of the sample shall be performed to identify the major radioactive constituents present in the sample and the appropriate doses shall be calculated and summed to determine compliance with s. NR 809.51 (1) using the formula in s. NR 809.51 (2). Doses shall also be calculated and combined for measured levels of tritium and strontium to determine compliance.

NR 809.53(2)(f) (f) Water suppliers for community water systems shall monitor monthly at the sampling points that exceed the maximum contaminant level in s. NR 809.51 beginning the month after the exceedance occurs. Water suppliers shall continue monthly monitoring until the water supplier has established, by a rolling average of 3 monthly samples, that the MCL is being met. Water suppliers for community water systems that establish that the MCL is being met shall return to quarterly monitoring until the requirements in par. (a) 1. or (b) 4. are met.

NR 809.53(3) (3) General monitoring and compliance requirements for radionuclides.

NR 809.53(3)(a) (a) The department may require more frequent monitoring than specified in subs. (1) and (2), or may require confirmation samples at its discretion. The results of the initial and confirmation samples shall be averaged for use in compliance determinations.

NR 809.53(3)(b) (b) Water suppliers for each public water system shall monitor at the time designated by the department during each compliance period.

NR 809.53(3)(c) (c) Compliance with ss. NR 809.50 (1) and 809.51 (1) shall be determined based on the analytical results obtained at each sampling point. If one sampling point is in violation of an MCL, the community water system is in violation of the MCL. In addition:

NR 809.53(3)(c)1. 1. For community water systems monitored more than once per year, compliance with the MCL is determined by using a running annual average calculated for each sampling point. If the average of any sampling point is greater than the MCL, the community water system is out of compliance with the MCL.

NR 809.53(3)(c)2. 2. For community water systems monitored more than once per year, if any sample result will cause the running annual average to exceed the MCL at any sample point, the community water system is out of compliance with the MCL immediately.

NR 809.53(3)(c)3. 3. For community water systems on reduced monitoring where monitoring results exceed an MCL, and a community water system is placed on quarterly monitoring as required by sub. (1) (d) 5., compliance with the MCL is determined based on a running annual average at each sample point, as required by sub. (3) (c) 1. if sample results exceed the MCL.

NR 809.53(3)(c)4. 4. Water suppliers for community water systems shall include all samples taken and analyzed under this section in determining compliance, even if that number is greater than the minimum required.

NR 809.53(3)(c)5. 5. If a water supplier for a community water system does not collect all required samples when compliance is based on a running annual average of quarterly samples, compliance shall be based on the running average of the samples collected.

NR 809.53(3)(c)6. 6. If a sample result is less than the detection limit, zero will be used to calculate the annual average, unless a gross alpha particle activity is being used in lieu of radium-226 or uranium, or both. If the gross alpha particle activity result is less than detection, 1/2 the detection limit shall be used to calculate the annual average.

NR 809.53(3)(d) (d) The department may delete results of obvious sampling or analytic errors.

NR 809.53 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (1) (d) 1. Register March 2016 No. 723, eff. 4-1-16.

subch. II of ch. NR 809 Subchapter II — Control of Lead and Copper

NR 809.54 NR 809.54 General requirements for the control of lead and copper.

NR 809.54(1) (1) Applicability.

NR 809.54(1)(a) (a) The requirements of this subchapter constitute the primary drinking water regulations for lead and copper. Unless otherwise indicated, each of the provisions of this subchapter applies to community water systems and non-transient, non-community water systems.

NR 809.54(2) (2) Scope. These regulations establish a treatment technique that includes requirements for corrosion control treatment, source water treatment, lead service line replacement and public education. These requirements are triggered, in some cases, by lead and copper action levels measured in samples collected at consumers’ taps.

NR 809.54(3) (3) Lead and copper action levels.

NR 809.54(3)(a) (a) The lead action level is exceeded if the concentration of lead in more than 10% of tap water samples collected during any monitoring period conducted in accordance with s. NR 809.547 is greater than 0.015 mg/L, which means if the “90th percentile” lead level is greater than 0.015 mg/L.

NR 809.54(3)(b) (b) The copper action level is exceeded if the concentration of copper in more than 10% of tap water samples collected during any monitoring period conducted in accordance with s. NR 809.547 is greater than 1.3 mg/L, which means if the “90th percentile” copper level is greater than 1.3 mg/L.

NR 809.54(3)(c) (c) The 90th percentile lead and copper levels shall be computed as follows:

NR 809.54(3)(c)1. 1. The results of all lead or copper samples taken during a monitoring period shall be placed in ascending order from the sample with the lowest concentration to the sample with the highest concentration. Each sampling result shall be assigned a number, ascending by single integers beginning with the number 1 for the sample with the lowest contaminant level. The number assigned to the sample with the highest contaminant level shall be equal to the total number of samples taken.

NR 809.54(3)(c)2. 2. The number of samples taken during the monitoring period shall be multiplied by 0.9.

NR 809.54(3)(c)3. 3. The contaminant concentration in the numbered sample yielded by the calculation in subd. 2. is the 90th percentile contaminant level.

NR 809.54(3)(c)4. 4. For water public water systems serving fewer than 100 people that are sampled at a rate of 5 samples per monitoring period, the 90th percentile is computed by taking the average of the highest and second highest concentrations.

NR 809.54(3)(c)5. 5. For a public water system that has been allowed by the department to be sampled at a rate of fewer than five samples in accordance with federal rule 40 CFR 141.86(c), the sample result with the highest concentration is considered the 90th percentile value.

NR 809.54(4) (4) Corrosion control treatment requirements.

NR 809.54(4)(a) (a) All water suppliers shall install and operate optimal corrosion control treatment as defined in s. NR 809.04.

NR 809.54(4)(b) (b) Any public water system that complies with the applicable corrosion control treatment requirements specified by the department under ss. NR 809.542 and 809.543 shall be deemed in compliance with the treatment requirement contained in par. (a).

NR 809.54(5) (5) Source water treatment requirements. Any water supplier for a public water system exceeding the lead or copper action level shall implement all applicable source water treatment requirements specified by the department under s. NR 809.544.

NR 809.54(6) (6) Lead service line replacement requirements. Any water supplier for a public water system exceeding the lead action level after implementation of applicable corrosion control and source water treatment requirements shall complete the lead service line replacement requirements contained in s. NR 809.545.

NR 809.54(7) (7) Public education requirements. Any water supplier for a public water system exceeding the lead action level shall implement the public education requirements contained in s. NR 809.546. Any water supplier for a public water system exceeding the copper action level shall annually provide public education on the health effects of copper using language in Appendix B to subch. VII, and information on reducing exposure to copper in drinking water similar to s. NR 809.546.

NR 809.54 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; correction in (3) (c) 5. made under s. 35.17, Stats., Register December 2018 No. 756.

NR 809.541 NR 809.541 Monitoring and analytical requirements for lead and copper.

NR 809.541(1) (1) General. Tap water monitoring for lead and copper, monitoring for water quality parameters, and source water monitoring for lead and copper shall be completed in compliance with ss. NR 809.548 and 809.549. The analyses shall be conducted using methods as prescribed in s. NR 809.113 (1), Table A. Holding times and preservation for Lead and Copper shall be done in accordance with s. NR 809.113, Table B. In all cases, samples should be analyzed as soon after collection as possible.

NR 809.541(2) (2) Use of previously collected data. The department may allow the use of previously collected monitoring data for the purposes of monitoring if the data were collected and analyzed in accordance with the requirements of this subchapter.

NR 809.541(3) (3) Laboratory certification. Analyses for alkalinity, calcium, conductivity, orthophosphate, pH, silica, and temperature may be performed by any person acceptable to the department. Analyses under this section for lead and copper shall only be conducted by laboratories that have been certified by EPA or the department. To obtain certification to conduct analyses for lead and copper, laboratories shall meet all of the requirements in sub. (4) (a) to (c).

NR 809.541(4) (4) Laboratory evaluation samples. For certification under sub. (3) laboratories shall analyze performance evaluation samples, which include lead and copper, provided by or acceptable to EPA or the department at least once a year by each method for which the laboratory desires certification; and the following:

NR 809.541(4)(a) (a) Achieve quantitative acceptance limits as follows:

NR 809.541(4)(a)1. 1. For lead: ±30 percent of the actual amount in the Performance Evaluation sample when the actual amount is greater than or equal to 0.005 mg/L. The Practical Quantitation Level, or PQL for lead is 0.005 mg/L.

NR 809.541(4)(a)2. 2. For copper: ±10 percent of the actual amount in the Performance Evaluation sample when the actual amount is greater than or equal to 0.050 mg/L. The Practical Quantitation Level, or PQL for copper is 0.050 mg/L.

NR 809.541(4)(b) (b) Achieve the method detection limit for lead of 0.001 mg/L according to the procedures in appendix B of 40 CFR part 136. This need only be accomplished if the laboratory will be processing source water composite samples under s. NR 809.549 (1) (a) 4.

NR 809.541(4)(c) (c) Be currently certified by EPA or the department under ch. NR 149 to perform analyses to the specifications described in pars. (a) and (b).

NR 809.541(5) (5) Data reporting requirements. Laboratories shall report data as follows:

NR 809.541(5)(a) (a) All lead and copper levels measured between the PQL and MDL shall be either reported as measured or they can be reported as one-half the PQL specified for lead and copper in par. (a). All levels below the lead and copper MDLs shall be reported as zero.

NR 809.541(5)(b) (b) All copper levels measured between the PQL and the MDL shall be either reported as measured or they can be reported as one-half the PQL at 0.025 mg/L. All levels below the copper MDL shall be reported as zero.

NR 809.541(6) (6) Treatment reporting requirements. Water suppliers shall report to the department any information required by the treatment provisions of this subchapter and s. NR 809.55.

NR 809.541(7) (7) Recordkeeping requirements. Water suppliers shall maintain records in accordance with s. NR 809.82.

NR 809.541(8) (8) Violation of national primary drinking water regulations. Failure to comply with the applicable requirements of ss. NR 809.113, 809.541 to 809.549, 809.80, and 809.82, including requirements established by the department pursuant to these provisions, shall constitute a violation of the primary drinking water regulations for lead or copper, or both.

NR 809.541(9) (9) Premise owner notification of lead and copper results. Water suppliers shall provide owners or occupants of all premises used in the lead and copper monitoring program the analytical results of all samples collected at that site. If sample results at a sample location exceed 15 ug/L for lead and 1300 ug/L for copper, water supplier shall inform premise owners or occupants of health effects and measures necessary to lower lead or copper levels.

NR 809.541 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; correction in (4) (b) made under s. 13.92 (4) (b) 7., Stats., Register January 2013 No. 685; CR 15-049: am. (4) (c) Register March 2016 No. 723, eff. 4-1-16.

NR 809.542 NR 809.542 Applicability of corrosion control treatment steps for small, medium and large-size water systems.

NR 809.542(1) (1) Corrosion control treatment requirements. Water suppliers shall complete the applicable corrosion control treatment requirements described in s. NR 809.543 by the deadlines established.

NR 809.542(1)(a) (a) The water supplier for a large system shall complete the corrosion control treatment steps specified in sub. (4), unless the public water system is deemed to have optimized corrosion control under sub. (2) (b) or (c).

NR 809.542(1)(b) (b) The water supplier for a small system and a medium-size system shall complete the corrosion control treatment steps specified in sub. (5), unless the public water system is deemed to have optimized corrosion control under sub. (2) (a), (b) or (c).

NR 809.542(2) (2) Determination of optimum corrosion control. A public water system is deemed to have optimized corrosion control and is not required to complete the applicable corrosion control treatment steps identified in this section if the public water system satisfies one of the criteria specified in pars. (a) to (c). Any public water system deemed to have optimized corrosion control under this subsection, and which has treatment in place, shall continue to operate and maintain optimal corrosion control treatment and meet any requirements that the department determines appropriate to ensure optimal corrosion control treatment is maintained.

NR 809.542(2)(a) (a) A small or medium-size water system is deemed to have optimized corrosion control if the public water system meets the lead and copper action levels during each of 2 consecutive 6-month monitoring periods conducted in accordance with s. NR 809.547.

NR 809.542(2)(b) (b) Any public water system may be deemed by the department to have optimized corrosion control treatment if the water supplier demonstrates to the satisfaction of the department that they have conducted activities equivalent to the corrosion control steps applicable to the public water systems under this section. If the department makes this determination, it shall provide the water supplier with written notice explaining the basis for its decision and shall specify the water quality control parameters representing optimal corrosion control in accordance with s. NR 809.543 (6). Public water systems deemed to have optimized corrosion control under this paragraph shall operate in compliance with the department-designated optimal water quality control parameters in accordance with s. NR 809.543 (8) and continue to conduct lead and copper tap and water quality parameter sampling in accordance with ss. NR 809.547 (4) (c) and 809.548 (4), respectively. A water supplier shall provide the department with all of the following information in order to support a determination under this subsection:

NR 809.542(2)(b)1. 1. The results of all test samples collected for each of the water quality parameters in s. NR 809.543 (3) (c).

NR 809.542(2)(b)2. 2. A report explaining the test methods used by the water supplier to evaluate the corrosion control treatments listed in s. NR 809.543 (3) (a), the results of all tests conducted, and the basis for the water supplier’s selection of optimal corrosion control treatment.

NR 809.542(2)(b)3. 3. A report explaining how corrosion control has been installed and how it is being maintained to insure minimal lead and copper concentrations at consumers’ taps.

NR 809.542(2)(b)4. 4. The results of tap water samples collected in accordance with s. NR 809.547 at least once every 6 months for one year after corrosion control has been installed.

NR 809.542(2)(c) (c) Any public water system is deemed to have optimized corrosion control if the water supplier submits results of tap water monitoring conducted in accordance with s. NR 809.547 and source water monitoring conducted in accordance with s. NR 809.549 that demonstrates for 2 consecutive 6-month monitoring periods that the difference between the 90th percentile tap water lead level computed under s. NR 809.54 (3) (c), and the highest source water lead concentration, is less than the practical quantitation level for lead specified in 40 CFR 141.89(a)(1)(ii).