Chapter NR 809

NR 809.327(4)(a)3.c. c. Alternatively, water suppliers for non-community groundwater systems that serve 3,300 or fewer people may monitor continuously in order to meet the requirements of subd. 1.

NR 809.327(4)(b) (b) Membrane filtration. A water supplier for a groundwater system that uses membrane filtration to meet the requirements of sub. (2) shall monitor the membrane filtration process in accordance with all department specified monitoring requirements and shall operate the membrane filtration in accordance with all department specified compliance requirements. To be in compliance with the requirement to achieve at least 4-log treatment of viruses when a public water system uses membrane filtration exclusively, the public water system shall meet all of the following:

NR 809.327(4)(b)1. 1. The membrane shall have an absolute molecular weight cut-off (MWCO), or an alternate parameter that describes the exclusion characteristics of the membrane, that can reliably achieve at least 4-log removal of viruses.

NR 809.327(4)(b)2. 2. The membrane process shall be operated in accordance with department-specified compliance requirements.

NR 809.327(4)(b)3. 3. The integrity of the membrane is intact.

NR 809.327(4)(b)4. 4. The public water system shall be provided with at least 2 log of additional treatment of viruses using a chemical disinfectant.

NR 809.327(4)(c) (c) Alternative treatment. A water supplier for a groundwater system that uses a department-approved alternative treatment to meet the requirements of sub. (2) (d) for providing at least 4-log treatment of viruses before or at the first customer shall do all of the following:

NR 809.327(4)(c)1. 1. Monitor the alternative treatment in accordance with all department specified monitoring requirements.

NR 809.327(4)(c)2. 2. Operate the alternative treatment in accordance with all compliance requirements that the department determines to be necessary to achieve at least 4-log treatment of viruses.

NR 809.327(5) (5) Discontinuing treatment. A water supplier for a groundwater system may discontinue 4-log treatment of viruses before or at the first customer for a groundwater source if the department determines and documents in writing that 4-log treatment of viruses is no longer necessary for that water source. A public water system where 4-log treatment of viruses is discontinued is subject to the source water monitoring requirements of s. NR 809.325.

NR 809.327(6) (6) Failure to meet monitoring requirements. If a water supplier fails to meet any of the monitoring requirements of sub. (4), the public water system is in violation and the water supplier shall complete public notification requirements under s. NR 809.953.

NR 809.327 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; correction in (4) (a) 2. b. made under s. 13.92 (4) (b) 7., Stats., Register November 2010 No. 659; CR 15-049: am. (1) (a), (c) (intro.), (3) (a) 2., (4) (a) 3., (6) Register March 2016 No. 723, eff. 4-1-16.

NR 809.328 NR 809.328 Treatment technique compliance for groundwater source microbiological contaminants.

NR 809.328(1) (1) Treatment technique violations for groundwater systems.

NR 809.328(1)(a) (a) A groundwater system with a significant deficiency is in violation of the treatment technique requirement if, within 120 days of the water supplier receiving written notice from the department of the significant deficiency or earlier if directed by the department, subd. 1. or 2. are not met.

NR 809.328(1)(a)1. 1. The water supplier has not completed a corrective action in accordance with any applicable department plan approval processes under chs. NR 811 and 812, including any department specified interim actions.

NR 809.328(1)(a)2. 2. The public water system is not in compliance with a department-approved corrective action plan and schedule.

NR 809.328(1)(b) (b) Unless the department invalidates an E. coli-positive groundwater source sample collected under s. NR 809.325, a public water system is in violation of the treatment technique requirement under s. NR 809.327 if within 120 days or earlier if directed by the department, the conditions of subd. 1. or 2 are not met.

NR 809.328(1)(b)1. 1. The water supplier does not complete corrective action in accordance with any applicable department plan review processes under chs. NR 811 and 812, including department specified interim measures.

NR 809.328(1)(b)2. 2. The public water system is not in compliance with a department-approved corrective action plan and schedule.

NR 809.328(1)(c) (c) A water supplier for a groundwater system subject to the requirements of s. NR 809.327 (4) that fails to maintain at least 4-log treatment of viruses before or at the first customer for a groundwater source is in violation of the treatment technique requirement if the failure is not corrected within 4 hours of determining the public water system is not maintaining at least 4-log treatment of viruses before or at the first customer.

NR 809.328(2) (2) public notification for treatment technique violations. Water suppliers for groundwater systems shall give public notification under s. NR 809.952 for the treatment technique violations specified under this section.

NR 809.328 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (1) (b) (intro.) Register March 2016 No. 723, eff. 4-1-16.

NR 809.329 NR 809.329 Reporting and recordkeeping requirements for groundwater systems.

NR 809.329(1) (1) Reporting. In addition to the requirements of ss. NR 809.31 and 809.80, a water supplier for a groundwater system regulated under s. NR 809.32 shall provide the following information to the department:

NR 809.329(1)(a) (a) A water supplier for a groundwater system conducting compliance monitoring under s. NR 809.327 (3) shall notify the department any time the public water system fails to meet any department-specified requirements including, but not limited to, minimum residual disinfectant concentration, membrane operating criteria or membrane integrity, and alternative treatment operating criteria, if the operation is not restored in accordance with the criteria or requirements within four hours. The water supplier shall notify the department as soon as possible, but in no case later than the end of the next business day after the failure.

NR 809.329(1)(b) (b) After completing any corrective action under s. NR 809.327 (2), a water supplier shall notify the department within 30 days of completion of the corrective action.

NR 809.329(2) (2) Recordkeeping. In addition to the requirements of s. NR 809.80, a water supplier for a public water system regulated under s. NR 809.32 shall maintain the following information in its records:

NR 809.329(2)(a) (a) Documentation of corrective actions. Documentation shall be kept for a period of not less than ten years.

NR 809.329(2)(b) (b) Documentation of notice to the public as required under s. NR 809.80. Documentation shall be kept for a period of not less than three years.

NR 809.329(2)(c) (c) Records of decisions under s. NR 809.325 (4) and records of invalidation of an E. coli-positive groundwater source sample under s. NR 809.323 (2). Documentation shall be kept for a period of not less than five years.

NR 809.329(2)(d) (d) For consecutive systems, documentation of notification to its wholesale systems of total-coliform positive samples that are not invalidated under s. NR 809.31 (3). Documentation shall be kept for a period of not less than five years.

NR 809.329(2)(e) (e) For public water systems, including wholesale systems, which are required to perform compliance monitoring under s. NR 809.327 (4) all of the following apply:

NR 809.329(2)(e)1. 1. Records of the department specified minimum disinfectant residual. Documentation shall be kept for a period of not less than ten years.

NR 809.329(2)(e)2. 2. Records of the lowest daily residual disinfectant concentration and records of the date and duration of any failure to maintain the department prescribed minimum residual disinfectant concentration for a period of more than four hours. Documentation shall be kept for a period of not less than five years.

NR 809.329(2)(e)3. 3. Records of department-specified compliance requirements for membrane filtration and of parameters specified by the department for department-approved alternative treatment and records of the date and duration of any failure to meet the membrane operating, membrane integrity, or alternative treatment operating requirements for more than 4 hours. Documentation shall be kept for a period of not less than five years.

NR 809.329 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (2) (c), (d), (e) (intro.) Register March 2016 No. 723, eff. 4-1-16.

NR 809.33 NR 809.33 Surface water microbiological organisms and indicators.

NR 809.33(1) (1) General requirements. The requirements in this section establish or extend treatment techniques in lieu of maximum contaminant levels for Cryptosporidium. These requirements are in addition to requirements for filtration and disinfection in subch. II of ch. NR 810.

NR 809.33(2) (2) Applicability. These requirements apply to all surface water and GWUDI public water systems.

NR 809.33(2)(a) (a) Wholesale systems that supply water from a surface water or GWUDI source shall comply with the requirements of this section based on the population of the largest public water system in the combined distribution system.

NR 809.33(2)(b) (b) The requirements of this section for filtered public water systems apply to all public water systems required by s. NR 810.29 to provide filtration treatment, whether or not the public water system is currently operating a filtration system.

NR 809.33(2)(c) (c) The requirements of this section for unfiltered public water systems apply only to unfiltered public water systems that met and continue to meet the filtration avoidance criteria in s. NR 810.30 as applicable.

NR 809.33(3) (3) Requirements. Public water systems subject to this section shall comply with the following requirements:

NR 809.33(3)(a) (a) The following monitoring is required under this section:

NR 809.33(3)(a)1. 1. Water suppliers shall have conducted and submitted to EPA an initial round of source water monitoring for treatment plants existing as of January 5, 2006 under 40 CFR part 141 National Primary Drinking Water Regulations Subpart W that determined the level of treatment for Cryptosporidium needed under s. NR 810.34.

NR 809.33(3)(a)2. 2. Water suppliers shall conduct source water monitoring as part of the treatment approval process for plants constructed after January 5, 2006 under s. NR 811.21 (1) (f). This monitoring shall include Cryptosporidium, E. coli, and turbidity to determine what level of Cryptosporidium treatment shall be provided using the requirements of the bin classifications under s. NR 810.34.

NR 809.33(3)(a)3. 3. A second round of source water monitoring for each plant that treats a surface water or GWUDI source shall be conducted by the water supplier and submitted to the department as required in s. NR 809.331 (2). This monitoring may include sampling for Cryptosporidium, E. coli, and turbidity as described in ss. NR 809.331 to 809.336, to determine what level, if any, of additional Cryptosporidium treatment the public water system shall provide.

NR 809.33(3)(b) (b) Water suppliers that plan to make a significant change to the disinfection practice at a public water system shall develop disinfection profiles and calculate disinfection benchmarks, as described in s. NR 810.32.

NR 809.33(3)(c) (c) Water suppliers for filtered public water systems shall determine their Cryptosporidium treatment bin classification as described in s. NR 810.34 and provide additional treatment for Cryptosporidium, if required, as described in s. NR 810.35. All unfiltered public water systems shall provide treatment for Cryptosporidium as described in s. NR 810.36. Filtered and unfiltered public water systems shall implement Cryptosporidium treatment according to the schedule in s. NR 810.37.

NR 809.33(3)(d) (d) Water suppliers for public water systems with an uncovered finished water storage facilities shall comply with the requirements to cover the facility or treat the discharge from the facility as described in s. NR 810.28.

NR 809.33(3)(e) (e) Water suppliers for public water systems required to provide additional treatment for Cryptosporidium shall implement microbial toolbox options that are designed and operated as described in ss. NR 810.41 to 810.46.

NR 809.33(3)(f) (f) Water supplier shall comply with the applicable recordkeeping and reporting requirements described in ss. NR 809.336 and 809.82.

NR 809.33(4) (4) Surface water treatment technique violations. Surface water and GWUDI public water systems are in violation of the treatment technique requirements for turbidity if any of the requirements of s. NR 810.29 (1) to (4) are not met.

NR 809.33 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (4) Register March 2016 No. 723, eff. 4-1-16.

NR 809.331 NR 809.331 Surface water source monitoring.

NR 809.331(1) (1) Initial round of source water monitoring. Water suppliers shall have conducted the following monitoring according to the schedule in sub. (3) Table H, at treatment plants existing as of January 5, 2006 unless the public water system meets the monitoring exemption criteria in sub. (4). The initial source water monitoring requirements were conducted under 40 CFR part 141 National Primary Drinking Water Regulations Subpart W with EPA wholly responsible for implementation. For public water systems with treatment plants constructed after January 5, 2006 the department may require the following initial monitoring as part of the approval process under s. NR 811.21 (1) (f).

NR 809.331(1)(a) (a) Water suppliers for filtered public water systems serving at least 10,000 people shall sample their source water for Cryptosporidium, E. coli, and turbidity at least monthly for 24 months.

NR 809.331(1)(b) (b) Water suppliers for unfiltered public water systems serving at least 10,000 people shall sample their source water for Cryptosporidium at least monthly for 24 months.

NR 809.331(1)(c) (c) Water suppliers for filtered public water systems serving fewer than 10,000 people shall sample their source water for E. coli at least once every two weeks for 12 months. A filtered public water system serving fewer than 10,000 people may avoid E. coli monitoring if the water supplier notifies the department that Cryptosporidium will be monitored for as described in sub. (3). The water supplier shall notify the department no later than 3 months prior to the date the public water system is required to start E. coli monitoring under sub. (3).

NR 809.331(1)(d) (d) Water suppliers for filtered public water systems serving fewer than 10,000 people shall sample their source water for Cryptosporidium at least twice per month for 12 months or at least monthly for 24 months if based on monitoring conducted under par. (c), and if they meet one of the following:

NR 809.331(1)(d)1. 1. For public water systems using lake or reservoir sources, the annual mean E. coli concentration is greater than 10 E. coli /100 mL.

NR 809.331(1)(d)2. 2. For public water systems using flowing stream sources, the annual mean E. coli concentration is greater than 50 E. coli /100 mL.

NR 809.331(1)(d)3. 3. The public water system was not monitored for E. coli as described in par. (c).

NR 809.331(1)(d)4. 4. Public water systems using groundwater under the direct influence of surface water (GWUDI) shall comply with the requirements of this paragraph based on the E. coli level that applies to the nearest surface water body. If no surface water body is nearby, the public water system shall comply based on the requirements that apply to public water systems using lake or reservoir sources.

NR 809.331(1)(e) (e) For filtered public water systems serving fewer than 10,000 people, the department may approve monitoring for an indicator other than E. coli under par. (c). The department also may approve an alternative to the E. coli concentration in par. (d) 1. to 3. to trigger Cryptosporidium monitoring. This approval by the department shall be provided to the public water system in writing and shall include the basis for the department’s determination that the alternative indicator or trigger level will provide a more accurate identification of whether a public water system will exceed the Bin 1 Cryptosporidium level in s. NR 810.34.

NR 809.331(1)(f) (f) Water suppliers for unfiltered public water systems serving fewer than 10,000 people shall sample their source water for Cryptosporidium at least twice per month for 12 months or at least monthly for 24 months.

NR 809.331(1)(g) (g) Water suppliers may sample more frequently than required under this section if the sampling frequency is evenly spaced throughout the monitoring period.

NR 809.331(2) (2) Second round of source water monitoring. Water supplier shall conduct a second round of source water monitoring that meets the requirements for monitoring parameters, frequency, and duration described in sub. (1), unless they meet the monitoring exemption criteria in sub. (4). Water suppliers shall conduct this monitoring on the schedule in sub. (3).

NR 809.331(3) (3) Monitoring schedule. According to EPA requirements, water supplier shall begin the monitoring required in subs. (1) and (2) no later than the month beginning with the date listed in Table H:

TABLE H

Source Water Monitoring Starting Dates

- See PDF for table

1 Applies only to filtered public water systems.

2 Applies to filtered public water systems that meet the conditions of sub. (1) (e) and unfiltered public water systems.

NR 809.331(4) (4) Monitoring avoidance.

NR 809.331(4)(a) (a) Water suppliers for filtered public water systems are not required to conduct source water monitoring under this section if the public water system will provide a total of at least 5.5-log of treatment for Cryptosporidium, equivalent to meeting the treatment requirements of Bin 4 in s. NR 810.35.

NR 809.331(4)(b) (b) Water supplier for unfiltered public water systems are not required to conduct source water monitoring under this section if the public water system will provide a total of at least 3-log Cryptosporidium inactivation, equivalent to meeting the treatment requirements for unfiltered public water systems with a mean Cryptosporidium concentration of greater than 0.01 oocysts/L in s. NR 810.36.

NR 809.331(4)(c) (c) If a water supplier chooses to provide the level of treatment in par. (a) or (b), as applicable, rather than start source water monitoring, the water supplier shall notify the department in writing no later than the date the public water system is otherwise required to submit a sampling schedule for monitoring under s. NR 809.332. Alternatively, a water supplier may choose to stop sampling at any point after the public water system has initiated monitoring if the water supplier notifies the department in writing that the public water system will provide this level of treatment. Water supplier shall install and operate technologies to provide this level of treatment by the applicable treatment compliance date in s. NR 810.37.

NR 809.331(5) (5) Plants operating only part of the year. Water suppliers for public water systems with surface water treatment plants that operate for only part of the year shall conduct source water monitoring in accordance with this section, but with the following modifications:

NR 809.331(5)(a) (a) Water supplier shall sample their source water only during the months that the plant operates unless the department specifies another monitoring period based on plant operating practices.

NR 809.331(5)(b) (b) Water supplier for public water systems with plants that operate less than six months per year and that monitor for Cryptosporidium shall collect at least six Cryptosporidium samples per year during each of two years of monitoring. Samples shall be evenly spaced throughout the period the plant operates.

NR 809.331(6) (6) New sources.

NR 809.331(6)(a) (a) A water supplier for a public water system that begins using a new source of surface water or GWUDI after the public water system is required to begin monitoring under sub. (3) shall monitor the new source on a schedule the department approves. Source water monitoring shall meet the requirements of this section. The public water system shall also meet the bin classification and Cryptosporidium treatment requirements of ss. NR 810.34 and 810.35 or s. NR 810.36, as applicable, for the new source on a schedule the department approves.

NR 809.331(6)(b) (b) The requirements of this section apply to public water systems with surface water treatment plants that begin operation after the monitoring start date applicable to the public water system’s size under sub. (3).

NR 809.331(6)(c) (c) The water supplier shall begin a second round of source water monitoring no later than 6 years following initial bin classification under s. NR 810.34 or determination of the mean Cryptosporidium level under s. NR 810.36, as applicable.

NR 809.331(7) (7) Monitoring violation. Failure to collect any source water sample required under this section in accordance with the sampling schedule, sampling location, analytical method, approved laboratory, and reporting requirements of s. NR 809.332 to s. NR 809.336 is a monitoring violation.

NR 809.331(8) (8) Grandfathering monitoring data. The water supplier may use monitoring data collected prior to the applicable monitoring start date in sub. (3) to meet the initial source water monitoring requirements in sub. (1). This data, referred to as grandfathered data, may substitute for an equivalent number of months of data at the end of the monitoring period. All data submitted under this section shall meet the requirements in s. NR 809.334.

NR 809.331 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; correction in (8) made under s. 13.92 (4) (b) 7., Stats., Register November 2010 No. 659.