NR 809.569 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 15-049: am. (1) (b) Table V, 3., (2) (c) 2.
Register March 2016 No. 723, eff. 4-1-16.
NR 809.60
NR 809.60 General requirements for Stage 2 DBP disinfection byproducts control. NR 809.60(1)(1)
General. The following establish monitoring and other requirements for achieving compliance with maximum contaminant levels based on locational running annual averages (LRAA) for total trihalomethanes (TTHM) and haloacetic acids five (HAA5), and for achieving compliance with maximum residual disinfectant levels for chlorine and chloramine for certain consecutive systems.
NR 809.60(2)
(2)
Applicability. A public water system is subject to these requirements if the public water system is a community water system or a nontransient noncommunity water system that uses a primary or residual disinfectant other than ultraviolet light or delivers or receives water that has been treated with a primary or residual disinfectant other than ultraviolet light.
NR 809.60(3)
(3)
Schedule. Public water systems shall comply with the requirements on the schedule in Table X based on public water system population:
-
See PDF for table 
1 The department may grant up to an additional 24 months for compliance with MCLs and operational evaluation levels if the public water system requires capital improvements to comply with an MCL.
NR 809.60(4)(a)
(a) Water suppliers for public water systems required to be monitored quarterly shall begin monitoring in the first full calendar quarter that includes the compliance date in the table in sub.
(3).
NR 809.60(4)(b)
(b) Water suppliers for public water systems required to be monitored at a frequency less than quarterly shall begin monitoring in the calendar month recommended in the initial distribution system evaluation (IDSE) report they prepared for the EPA under Subpart U of
40 CFR part 141 or in the calendar month identified in the monitoring plan developed under s.
NR 809.62 which shall be no later than 12 months after the compliance date in the table in par.
(3).
NR 809.60(4)(c)
(c) Water suppliers for public water systems required to be monitored quarterly, shall make compliance calculations at the end of the fourth calendar quarter that follows the compliance date and at the end of each subsequent quarter or earlier if the LRAA calculated based on fewer than four quarters of data would cause the MCL to be exceeded regardless of the monitoring results of subsequent quarters.
NR 809.60(4)(d)
(d) If the public water system is required to be monitored at a frequency that is less than quarterly, the water supplier shall make compliance calculations beginning with the first compliance sample taken after the compliance date.
NR 809.60(5)
(5)
Consecutive systems. The department may determine that a public water system that receives some or all of its water supply from a wholesale system is not a consecutive system, based on any of the following factors:
NR 809.60(5)(a)
(a) Receives water from a wholesale system only on an emergency basis.
NR 809.60(5)(b)
(b) Receives only a small percentage and small volume of water from a wholesale system.
NR 809.60(6)
(6)
Wholesale systems. The department may determine that a public water system that provides some or all of the water supply for another public water system is not a wholesale system, based on any of the following factors:
NR 809.60(6)(a)
(a) Delivers water to a consecutive system only on an emergency basis.
NR 809.60(6)(b)
(b) Delivers only a small percentage and small volume of water to a consecutive system.
NR 809.60(7)(a)
(a) Water suppliers for public water systems required to be monitored quarterly shall calculate LRAAs for TTHM and HAA5 to determine that each monitoring location LRAA does not exceed the MCL.
NR 809.60(7)(a)1.
1. If four consecutive quarters of monitoring are not completed, compliance with the MCL shall be based on the average of the available data from the most recent four quarters.
NR 809.60(7)(a)2.
2. If more than one sample per quarter is collected at a monitoring location, all samples taken in the quarter at that location shall be averaged to determine a quarterly average to be used in the LRAA calculation.
NR 809.60(7)(b)
(b) Water suppliers for public water systems required to be monitored yearly or less frequently shall establish compliance for TTHM and HAA5 by using each sample collected to determine if it is less than the MCL.
NR 809.60(7)(b)2.
2. If no sample exceeds the MCL, the sample result for each monitoring location is considered the LRAA for that monitoring location.
NR 809.60(7)(c)
(c) A public water system is in violation of the monitoring requirements for each quarter that a LRAA is calculated using a quarter in which the water supplier failed to monitor.
NR 809.60 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 15-049: am. (3) Table X, (4) (b)
Register March 2016 No. 723, eff. 4-1-16.
NR 809.61
NR 809.61 Routine monitoring for Stage 2 DBP. NR 809.61(1)(a)(a) A water supplier that submitted an IDSE report to EPA under Subpart U of
40 CFR part 141 shall begin monitoring at the locations and months recommended in the IDSE report submitted to EPA under Subpart U of
40 CFR part 141.605 following the schedule in s.
NR 809.60 (3), unless the department requires other locations or additional locations after its review.
NR 809.61(1)(b)
(b) A water supplier that submitted a 40/30 certification from EPA under Subpart U of
40 CFR part 141.603 or the department under s.
NR 809.974 or for a public water system that qualified for a very small system waiver from EPA under Subpart U of
40 CFR 141.604 or the department under s.
NR 809.975 or for a public water system that is a nontransient noncommunity water system serving <10,000, shall monitor at the location or locations and dates identified in the public water system's monitoring plan in s.
NR 809.565 (6), updated as required by s.
NR 809.62.
NR 809.61 Note
Note: Sections NR 809.974 and 809.975 were repealed by
CR 15-049. Corrections will be made in future rulemaking.
NR 809.61(1)(d)
(d) All public water systems shall be monitored during the month of highest DBP concentrations.
NR 809.61(1)(e)
(e) Water suppliers for public water systems on quarterly monitoring shall take dual sample sets every 90 days at each monitoring location, except for water supplier for surface water systems or groundwater under the direct influence of surface water systems serving 500–3,300. Water suppliers for groundwater systems serving 500–9,999 on annual monitoring shall take dual sample sets at each monitoring location. All other public water systems on annual monitoring and surface water systems or groundwater under the direct influence of surface water systems serving 500–3,300 shall take individual TTHM and HAA5 samples, instead of a dual sample set, at the locations with the highest TTHM and HAA5 concentrations, respectively. For public water systems serving fewer than 500 people, only one location with a dual sample set per monitoring period is required if the highest TTHM and HAA5 concentrations occur at the same location and month.
NR 809.61(1)(f)
(f) Water suppliers for undisinfected systems that begin using a disinfectant other than UV light after the dates for complying with the Initial Distribution System Evaluation requirements shall consult with the department to identify compliance monitoring locations for s.
NR 809.60 and develop a monitoring plan under s.
NR 809.62 that includes those monitoring locations.
NR 809.61(2)(b)
(b) The analysis under par.
(a) shall be conducted by laboratories that are certified by EPA or the department under ch.
NR 149.
NR 809.61 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 15-049: am. (1) (a), (c) Table Y, (2) (a)
Register March 2016 No. 723, eff. 4-1-16.
NR 809.62
NR 809.62 Monitoring plan for Stage 2 DBP. NR 809.62(1)(1)
General monitoring plan requirements. Monitoring plans shall be developed, implemented and kept up to date by water suppliers for all public water systems that are required to be monitored for TTHMs and HAA5s and shall be kept on file for department and public review.
NR 809.62(1)(a)
(a) Monitoring plans under this section shall be completed no later than the date the public water system is required to begin initial compliance monitoring under s.
NR 809.60 (3).
NR 809.62(1)(b)
(b) The monitoring plan shall contain the all of the following elements:
NR 809.62(1)(b)4.
4. Monitoring plans for any other public water systems in a combined distribution system.
NR 809.62(1)(c)
(c) If a public water system was not required to submit an IDSE report to the EPA under Subpart U of
40 CFR 141.601 or
141.602 and does not have sufficient monitoring locations to identify the required number of locations indicated in Subpart U of
40 CFR 141.605(b) or under s.
NR 809.61; the water supplier shall do all of the following:
NR 809.62(1)(c)1.
1. Identify additional locations by alternating selection of locations representing high TTHM levels and high HAA5 levels until the required number of compliance monitoring locations have been identified.
NR 809.62(1)(c)2.
2. Provide the rationale for identifying the locations as having high levels of TTHM or HAA5. Water suppliers should compare the number of monitoring locations required under s.
NR 809.565 with the number of monitoring locations under s.
NR 809.61 Table Y. If the public water system was required to have more monitoring locations under s.
NR 809.565 than under s.
NR 809.62 compliance monitoring, the water supplier shall identify which locations will be used by alternating selection of locations representing high TTHM levels and high HAA5 levels until the required number of compliance monitoring locations under s.
NR 809.61 Table Y have been identified.
NR 809.62(2)
(2)
Submittal of monitoring plans. If a public water system serves > 3,300 people, the water supplier shall submit a copy of a monitoring plan to the department prior to the date the water supplier for the public water system is required to conduct initial monitoring under s.
NR 809.60 (3), unless the IDSE report submitted under Subpart U of
40 CFR part 141 of the Federal Regulation contains all the information required by this subsection.
NR 809.62(3)
(3)
Revising monitoring plans. Water suppliers shall revise monitoring plans to reflect changes in treatment, distribution system operations and layout including new service areas, or other factors that may affect TTHM or HAA5 formation, or as approved by the department.
NR 809.62(3)(a)
(a) The department shall be consulted regarding the need for changes and the appropriateness of changes to a monitoring plan.
NR 809.62(3)(b)
(b) If monitoring locations are changed, existing compliance monitoring locations with the lowest LRAA shall be replaced with new locations that are expected have the highest TTHM or HAA5 levels in the distribution system.
NR 809.62(3)(c)
(c) The department may also require other modifications in the public water systems monitoring plan.
NR 809.62(3)(d)
(d) If the public water system serves > 3,300 people, the water supplier shall submit a copy of the modified monitoring plan to the department prior to the date the public water system is required to comply with the revised monitoring plan.
NR 809.62 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10; correction to numbering of (3) (a) to (d) made under s.
13.92 (4) (b) 1., Stats.,
Register November 2010 No. 659;
CR 15-049: am. (1) (a), (c) (intro.), 2., (2)
Register March 2016 No. 723, eff. 4-1-16; correction in (1) (c) made under s.
13.92 (4) (b) 7., Stats.,
Register December 2018 No. 756.
NR 809.63
NR 809.63 Requirements for reduced and increased monitoring for Stage 2 DBP. NR 809.63(1)(1)
Reduced monitoring. The department may reduce the monitoring frequency when the LRAA is less than or equal to 0.040 mg/L for TTHM and less than or equal to 0.030 mg/L for HAA5 at all compliance monitoring locations. Systems may only use data collected in compliance with s.
NR 809.565 and under this section to qualify for reduced monitoring. In addition, the source water annual average TOC level, before any treatment, must be
≤4.0 mg/L at each treatment plant treating surface water or GWUDI, based on monitoring conducted under s.
NR 809.565 (2) (c) 2m. The reduced sampling frequency and number of sample sites are given in Table Z:
-
See PDF for table NR 809.63(1)(a)
(a) Water suppliers for public water systems on quarterly monitoring shall take dual sample sets every 90 days.
NR 809.63(1)(b)
(b) Public water systems on annual monitoring and surface water or GWUDI systems serving 500 to 3,300 people may use a single site if the highest TTHM and HAA5 concentrations occur at the same time and place. Any such public water system may be required to take individual TTHM and HAA5 samples, instead of a dual sample set, at sites identified as the highest TTHM and HAA5 sites, respectively. If separate sites for individual TTHM and HAA5 samples are used, then the TTHM sample shall be collected during the quarter with highest historical TTHM levels and the HAA5 sample shall be collected during the quarter with the highest historical HAA5 level.
NR 809.63(1)(c)
(c) Only data collected under the provisions of s.
NR 809.565 and under this section may be used to qualify for reduced monitoring.
NR 809.63(1)(d)
(d) To remain on reduced monitoring, a public water system shall meet the following conditions:
NR 809.63(1)(d)1.
1. Public water systems on a quarterly reduced monitoring schedule may remain on that reduced schedule as long as the TTHM LRAA
<0.040 mg/L and the HAA5 LRAA
<0.030 mg/L at each monitoring location.
NR 809.63(1)(d)2.
2. Public water systems on an annual or less frequent reduced monitoring schedule may remain on that reduced schedule as long as each TTHM sample
<0.060 mg/L and each HAA5 sample
<0.045 mg/L.
NR 809.63(1)(d)3.
3. In addition to subds.
1. and
2., for a surface water or GWUDI system, the source water annual average TOC level, before any treatment, shall be
<4.0 mg/L, based on monitoring conducted under s.
NR 809.565 (2) (c) 2m. NR 809.63(1)(e)
(e) If the LRAA based on quarterly monitoring at any monitoring location exceeds either 0.040 mg/L for TTHM or 0.030 mg/L for HAA5 or if the annual (or less frequent) sample at any location exceeds either 0.060 mg/L for TTHM or 0.045 mg/L for HAA5, or if the source water annual average TOC level, before any treatment, is >4.0 mg/L at any treatment plant treating surface water or groundwater under the direct influence of surface water, the water supplier shall resume routine monitoring under s.
NR 809.61 or begin increased monitoring under sub.
(2).
NR 809.63(1)(f)
(f) The department may return a public water system to routine monitoring, at any time, at the department's discretion.
NR 809.63(2)(a)
(a) A public water system that is required to monitor at a particular location annually or less frequently than annually under s.
NR 809.62 or
809.63 (1), shall increase monitoring to dual sample sets once per quarter at all locations if a TTHM sample is >0.080 mg/L or a HAA5 sample is >0.060 mg/L at any location.
NR 809.63(2)(am)
(am) Water suppliers shall conduct increased monitoring under this paragraph at the monitoring locations in the monitoring plan developed under s.
NR 809.62 beginning on the date identified in s.
NR 809.60 (3) for compliance with this subchapter. The public water system shall remain on increased monitoring until it qualifies to return to routine monitoring under s.
NR 809.61.
NR 809.63(2)(b)
(b) Samples shall be taken every 90 days plus or minus 5 days beginning from the date of collection of the original sample that exceeded the MCL for either TTHM or HAA5.
NR 809.63(3)
(3)
MCL violation determination. A public water system is in violation of the MCL when the LRAA for TTHM or HAA5 exceeds the MCLs in s.
NR 809.561 (3), calculated based on four consecutive quarters of monitoring or the LRAA calculated based on fewer than four quarters of data if the MCL would be exceeded regardless of the monitoring results of subsequent quarters.
NR 809.63(4)
(4)
Return to routine monitoring. The department may return a public water system to routine monitoring once the water supplier has completed increased monitoring for at least four consecutive quarters and the LRAA for every monitoring location is
<0.060 mg/L for TTHM and
<0.045 mg/L for HAA5.
NR 809.63(5)
(5)
Violation of monitoring requirements. A public water system is in violation of the monitoring requirements if the water supplier fails to monitor during a quarter and for each subsequent quarter that the monitoring result would have been used in calculating a LRAA.
NR 809.63 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 15-049: am. (1) (intro.), (d) 3., (e), cr. (2) (am), am. (4) (title)
Register March 2016 No. 723, eff. 4-1-16; s.
35.17 correction made in (1) (intro.) under s.
35.17, Stats.,
Register March 2016.
NR 809.64
NR 809.64 Additional disinfection byproducts requirements for consecutive systems under Stage 2 DBP. A consecutive system that does not add a disinfectant but receives and delivers water that has been treated with a primary or residual disinfectant other than ultraviolet light, shall comply with analytical and monitoring requirements for chlorine and chloramines in s.
NR 809.565 (4) (a) and the compliance requirements in s.
NR 809.566 (3) (a) beginning April 1, 2009, unless required to comply earlier by the department, and shall report monitoring results under s.
NR 809.567 (3) (a).
NR 809.64 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10.
NR 809.65
NR 809.65 Operational evaluation levels for disinfection byproducts under Stage 2 DBP. NR 809.65(1)(1)
Operational evaluation. An operational evaluation shall be conducted if any of the following occurs:
NR 809.65(1)(a)
(a) The sum of the two previous quarters' TTHM results plus twice the current quarter's TTHM result, divided by 4, exceeds 0.080 mg/L at any monitoring location.
NR 809.65(1)(b)
(b) The sum of the two previous quarters' HAA5 results plus twice the current quarter's HAA5 result, divided by 4, exceeds 0.060 mg/L at any monitoring location.
NR 809.65(2)
(2)
Operational evaluation reporting. If an operational evaluation must be performed as required in sub.
(1), it shall be submitted as a written report to the department no later than 90 days after being notified of the analytical result that causes the public water system to exceed the operational evaluation level. The written report shall be made available to the public upon request.
NR 809.65(3)
(3)
Contents of an operational report. An operational evaluation shall include an examination of the system treatment and distribution operational practices, including storage tank operations, excess storage capacity, distribution system flushing, changes in sources or source water quality, and treatment changes or problems that may contribute to TTHM and HAA5 formation and what steps could be considered to minimize future exceedances.
NR 809.65(4)
(4)
Limiting the scope of an operational evaluation. A water supplier may request and the department may allow the water supplier to limit the scope of the operational evaluation if the water supplier is able to identify the cause of the operational evaluation level exceedance. The request to limit the scope of the evaluation does not extend the schedule required under sub.
(2) for submitting the written report. If the department approves this limited scope of evaluation, the approval shall be in writing and the water supplier shall keep the written approval with the completed report.
NR 809.65 History
History: CR 09-073: cr.
Register November 2010 No. 659, eff. 12-1-10;
CR 15-049: am. (1) (a), (b)
Register March 2016 No. 723, eff. 4-1-16.
NR 809.66
NR 809.66 Requirements for remaining on reduced TTHM and HAA5 monitoring based on Stage 1 DBP results. NR 809.66(1)(1)
Remaining on reduced monitoring. A public water system may remain on reduced monitoring after the dates identified in s.
NR 809.60 (3) for compliance with this subchapter only if the public water system qualified for a 40/30 certification by EPA under Subpart U of
40 CFR 141.603, or received a very small system waiver under Subpart U of
40 CFR 141.604, and if the public water system meets the reduced monitoring criteria in NR 809.63 (1) and all of the following criteria:
