NR 809.561(3)(b)(b) To achieve compliance with the maximum residual disinfectant levels identified in this subsection, water suppliers shall control treatment processes by reducing disinfectant demand and by controlling disinfection treatment processes to reduce disinfectant levels. NR 809.561(3)(c)(c) Free chlorine or total chlorine may be measured for demonstrating compliance with the chlorine MRDL. Combined chlorine or total chlorine may be used for demonstrating compliance with the chloramine MRDL. NR 809.561(4)(4) Best available treatment. The department, pursuant to section 1412 of the Safe Drinking Water Act and related regulations applicable to public water systems, identifies the following as the best available treatment technology, treatment techniques or other means available for achieving compliance with the maximum contaminant levels for disinfection byproducts identified in sub. (1): NR 809.561(5)(5) Alternative treatment. The department may approve the use of alternative treatment not listed in sub. (4), if a water supplier demonstrates to the department, using pilot studies or other means, that the alternative treatment is sufficient to achieve compliance with the MCLs in sub. (2). NR 809.561 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: cr. (3) (c), am. (4) Register March 2016 No. 723, eff. 4-1-16. NR 809.562NR 809.562 General requirements for disinfection byproducts and disinfection residuals Stage 1 DBP. NR 809.562(1)(1) General. The following requirements establish criteria under which water supplier for community water systems, or CWSs, and nontransient, noncommunity water systems, or NTNCWSs, which add a chemical disinfectant to the water in any part of the drinking water treatment process shall modify their practices to meet MCLs and MRDLs in s. NR 809.561 (2) and (3) (a), respectively, and shall meet the treatment technique requirements for disinfection byproduct precursors in s. NR 809.561 (4). Water suppliers for transient noncommunity water systems, or TNCWSs, that use chlorine dioxide as a disinfectant or oxidant shall modify their practices to meet the MRDL for chlorine dioxide in s. NR 809.561 (3) (a) according to the criteria established in this section. MCLs have been established for TTHM and HAA5 and treatment technique requirements for disinfection byproduct precursors to limit the levels of known and unknown disinfection byproducts which may have adverse health effects. These disinfection byproducts may include chloroform, bromodichloromethane, dibromochloromethane, bromoform, dichloroacetic acid, and trichloroacetic acid. NR 809.562(2)(2) Compliance timeframes. Unless otherwise noted, all public water systems shall comply with the requirements of this subchapter as follows: NR 809.562(2)(a)(a) All public water systems serving 10,000 or more persons that are CWSs or NTNCWSs and that are supplied by a surface water source or by a groundwater source under the direct influence of surface water shall comply with this subchapter beginning January 1, 2002. NR 809.562(2)(b)(b) Public water systems serving fewer than 10,000 persons that are CWSs or NTNCWSs and that are supplied by a surface water source or by a groundwater source under the direct influence of surface water and all public water systems using only groundwater not under the direct influence of surface water shall comply with this subchapter beginning January 1, 2004. NR 809.562(2)(c)(c) Public water systems serving 10,000 or more persons that are transient NCWSs and use chlorine dioxide as a disinfectant or oxidant and are supplied by a surface water source or by a groundwater source under the direct influence of surface water shall comply with any requirements for chlorine dioxide and chlorite in this subchapter beginning January 1, 2002. NR 809.562(2)(d)(d) Public water systems that are transient NCWSs and use chlorine dioxide as a disinfectant or oxidant and that serve fewer than 10,000 persons and are supplied by a surface water source or by a groundwater source under the direct influence of surface water or that are public water systems using only groundwater not under the direct influence of surface water shall comply with any requirements for chlorine dioxide in this subchapter beginning January 1, 2004. NR 809.562(2)(e)(e) A consecutive system that does not add a disinfectant but 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 (6) (a) and the compliance requirements in s. NR 809.566 (3) (a) beginning April 1, 2009 and shall report monitoring results under s. NR 809.567 (3). NR 809.562(3)(3) Operator certification. Each CWS and NTNCWS regulated under s. NR 809.561 shall be operated by qualified personnel who meet the requirements specified in ch. NR 114, subchs. I and III and are included in a department register of qualified operators. NR 809.562(4)(4) Response to microbiological contamination. Notwithstanding the MRDLs in s. NR 809.561 (3) (a), water suppliers for public water systems may increase in the distribution system residual disinfectant levels of chlorine or chloramines, but not chlorine dioxide, to a level and for a time necessary to protect public health, to address specific microbiological contamination problems caused by circumstances such as, but not limited to, distribution line breaks, storm run-off events, source water contamination events or cross-connection events. NR 809.562(5)(5) Public notification of MCL or MRDL violations. The water supplier of a public water system shall provide public notification in compliance with subch. VII when the MCL or MRDL or disinfectant residual is exceeded. NR 809.562(6)(6) Required additional health information. Water suppliers for CWSs that detect TTHM above 0.080 mg/l, but are not in violation of the MCL in s. NR 809.561 (2), based on an annual average, monitored and calculated under the provisions of s. NR 809.565, shall provide copies of health effects language prescribed in subch. VII and s. NR 809.835 to the users of the CWS in the CCR. NR 809.562 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (3) Register March 2016 No. 723, eff. 4-1-16; correction in (3) made under s. 35.17, Stats., Register March 2016 No. 723, eff. 4-1-16. NR 809.563NR 809.563 Analytical requirements for disinfection byproducts and disinfection residuals Stage 1 DBP and Stage 2 DBP. NR 809.563(1)(1) General. Water suppliers shall use only the analytical methods specified in this section, or otherwise approved by EPA for monitoring under this subchapter, to demonstrate compliance with the requirements of this subchapter. NR 809.563(2)(2) Approved analytical methods for disinfectant residuals. Water suppliers shall measure residual disinfectant concentrations for total chlorine, free chlorine, combined chlorine chloramines, and chlorine dioxide by the methods listed in Table R. Water suppliers may also measure residual disinfectant concentrations for chlorine, chloramines and chlorine dioxide by using N,N-diethly-p-phenylenediamine (DPD) colorimetric using a colorimeter as prescribed in the approved methods. NR 809.563(3)(3) Approved analytical methods for disinfectant byproducts. Water suppliers shall measure disinfection byproducts by the methods, as modified by the footnotes, prescribed in Table S. Samples for TTHM shall be dechlorinated upon collection to prevent further production of trihalomethanes, according to the procedures described in the methods, except acidification is not required if only THMs or TTHMs are to be determined. Samples for maximum TTHM potential shall not be dechlorinated or acidified, and shall be held for 7 days at 25° C or above prior to analysis. Samples for bromate analyzed using EPA method 321.8 samples must be preserved at the time of sampling with 50 mg ethylenediamine (EDA)/L of sample and must be analyzed within 28 days. Samples for TTHM and HAA5 shall be collected using the containers, preservative and holding times specified in s. NR 809.203 (4) Table D. In all cases, samples should be analyzed as soon after collection as possible. 1 X indicates method is approved for measuring specified disinfectant residual. Free chlorine or total chlorine may be measured for demonstrating compliance with the chlorine MRDL and combined chlorine, or total chlorine may be measured for demonstrating compliance with the chloramine MRDL.
2 Standard Methods for the Examination of Water and Wastewater, 19th edition (1995), 20th edition (1998), 21st edition (2005), 22nd edition (2012). Available from American Public Health Association, 800 I Street, NW., Washington, DC, 20001-3710.
3 The Standard Methods Online version that is approved is indicated by the last two digits in the method number which is the year of approval by the Standard Method Committee. Standard Methods Online are available athttp://www.standardmethods.org. 4 Available from ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2859, or http://astm.org. 1 P&T = purge and trap; GC = gas chromatography; ELCD = electrolytic conductivity detector; PID = photoionization detector; MS = mass spectrometer; LLE = liquid/liquid extraction; ECD = electron capture detector; SPE = solid phase extraction; IC = ion chromatography; ICP-MS= inductively coupled plasma/mass spectrometer.
2 Standard Methods for the Examination of Water and Wastewater, 19th edition (1995), 20th edition (1998), 21st edition (2005), 22nd edition (2012). Available from American Public Health Association, 800 I Street, NW., Washington, DC, 20001-3710.
3 Available from ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2859, or http://astm.org., 4 If TTHMs are the only analytes being measured in the sample, then a PID is not required.
5 The samples must be extracted within 14 days of sample collection.
6 Ion chromatography and post column reaction or IC/ICP-MS must be used for monitoring of bromate for purposes of demonstrating eligibility of reduced monitoring.
7 Samples must be preserved at the time of sampling with 50 mg ethylenediamine (EDA)/L of sample and must be analyzed within 28 days.
8 Amperometric titration or spectrophotometry may be used for routine daily monitoring of chlorite at the entrance to the distribution system, as prescribed in NR 809.565(3)(a)1. Ion chromatography must be used for routine monthly monitoring of chlorite and additional monitoring of chlorite in the distribution system, as prescribed in NR 809.565(30(a) 2. and. NR 809.565 (3) (a)3.
9 The Standard Methods Online version that is approved is indicated by the last two digits in the method number which is the year of approval by the Standard Method Committee. Standard Methods Online are available at http://www.standardmethods.org. NR 809.563(4)(4) Laboratory certification for disinfectant byproducts. Laboratories that are certified by the department or EPA shall conduct the analysis under this section for disinfection byproducts. NR 809.563(4)(a)(a) To receive certification to conduct analyses for the contaminants in this subchapter, a laboratory shall analyze performance evaluation samples approved by the department or EPA at least once during each consecutive 12-month period by each method for which a laboratory desires certification. NR 809.563(4)(b)(b) When analyzing performance evaluation samples, the laboratory shall achieve quantitative results on the PE sample analyses that are within the acceptance limits in Table T. NR 809.563(4)(c)(c) The acceptance limit shall be the 95% confidence interval calculated around the mean of the PE study data between a maximum and minimum acceptance limit of +/-50% and +/-15% of the study mean. NR 809.563(4)(e)(e) Laboratories shall report quantitative data for concentrations as low as the ones listed in Table U for all DBP samples analyzed for compliance. Table U
Minimum Reporting Levels for DBP Samples
1 The calibration curve must encompass the regulatory minimum reporting level (MRL) concentration. Data may be reported for concentrations lower than the regulatory MRL as long as the precision and accuracy criteria are met by analyzing an MRL check standard at the lowest reporting limit chosen by the laboratory. The laboratory must verify the accuracy of the calibration curve at the MRL concentration by analyzing an MRL check standard with a concentration less than or equal to 110% of the MRL with each batch of samples. The measured concentration for the MRL check standard must be ±50% of the expected value, if any field sample in the batch has a concentration less than 5 times the regulatory MRL. Method requirements to analyze higher concentration check standards and meet tighter acceptance criteria for them must be met in addition to the MRL check standard requirement.
2 When adding the individual trihalomethane or haloacetic acid concentrations to calculate the TTHM or HAA5 concentrations, respectively, a zero is used for any analytical result that is less than the MRL concentration for that DBP, unless otherwise specified by the department.
NR 809.563(5)(5) Approval of persons measuring disinfectant residual concentrations and chlorite. A person approved by the department or EPA shall measure residual disinfectant concentrations and daily chlorite samples at the entrance to the distribution system. NR 809.563(6)(6) Analytical methods for additional required parameters. Water suppliers for public water systems required to analyze for additional parameters not included in sub. (3) shall have these parameters analyzed by a person approved by the department or EPA using the following methods: NR 809.563(6)(b)(b) Bromide. For measuring bromide use EPA Method 300.0 or EPA Method 300.1. NR 809.563(6)(c)(c) Total organic carbon (TOC). For measuring total organic carbon, use Standard Method 5310 B (High-Temperature Combustion Method) or Standard Method 5310 C (Persulfate-Ultraviolet or Heated-Persulfate Oxidation Method) or Standard Method 5310 D (Wet-Oxidation Method). NR 809.563(6)(c)2.2. TOC samples shall either be analyzed or shall be acidified to achieve pH less than 2.0 by minimal addition of phosphoric or sulfuric acid as soon as practical after sampling, not to exceed 24 hours. NR 809.563(6)(d)(d) Specific ultraviolet absorbance (SUVA). SUVA is equal to the UV absorption at 254nm (UV254) measured in m-1 divided by the dissolved organic carbon (DOC) concentration measured as mg/L. NR 809.563(6)(d)1.1. In order to determine SUVA, it is necessary to separately measure UV254 and DOC. NR 809.563(6)(d)2.2. When determining SUVA, water suppliers shall use the methods stipulated in par. (e) to measure DOC and the method stipulated in par. (f) to measure UV254 SUVA shall be determined on water prior to the addition of disinfectants or oxidants, or both, by the water supplier. NR 809.563(6)(d)3.3. DOC and UV254 samples used to determine a SUVA value shall be taken at the same time and at the same location. NR 809.563(6)(e)(e) Dissolved organic carbon (DOC). For measuring dissolved organic carbon, use Standard Method 5310 B (High-Temperature Combustion Method) or Standard Method 5310 C (Persulfate-Ultraviolet or Heated-Persulfate Oxidation Method) or Standard Method 5310 D (Wet-Oxidation Method). Prior to analysis, DOC samples shall be filtered through a 0.45 mm pore-diameter filter. Water passed through the filter prior to filtration of the sample shall serve as the filtered blank. This filtered blank shall be analyzed using procedures identical to those used for analysis of the samples and shall meet the following criteria: DOC < 0.5 mg/L. DOC samples shall be filtered through the 0.45 mm pore-diameter filter prior to acidification. DOC samples shall either be analyzed or shall be acidified to achieve pH less than 2.0 by minimal addition of phosphoric or sulfuric acid as soon as practical after sampling, not to exceed 48 hours. Acidified DOC samples shall be analyzed within 28 days. NR 809.563(6)(f)(f) Ultraviolet absorption at 254 nm (UV254). For measuring ultraviolet absorption at 254 nm, use Method 5910 B (Ultraviolet Absorption Method). UV absorption shall be measured at 253.7 nm (may be rounded off to 254 nm). Prior to analysis, UV254 samples shall be filtered through a 0.45 mm pore-diameter filter. The pH of UV254 samples may not be adjusted. Samples shall be analyzed as soon as practical after sampling, not to exceed 48 hours. NR 809.563 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (1), (2), r. and recr. (2) Table R, (3) Table S, am. (4) (a), (b), r. (4) (d), am. (4) (e), Table U, (5), (6) (intro.), cr. (6) (h) Register March 2016 No. 723, eff. 4-1-16. NR 809.565NR 809.565 Monitoring requirements for disinfection byproducts and disinfection residuals Stage 1 DBP. NR 809.565(1)(1) General requirements. General requirements under this subchapter for analytical requirements, determining maximum contaminant levels, conducting monitoring and control of disinfection byproducts are as follows: NR 809.565(1)(a)(a) Water suppliers shall take all samples during normal operating conditions. NR 809.565(1)(b)(b) Water suppliers may consider multiple wells drawing water from a single aquifer as one treatment plant for determining the minimum number of TTHM and HAA5 samples required, on a case-by-case basis with department approval. NR 809.565(1)(c)(c) Failure to monitor in accordance with the monitoring plan required under sub. (6) is a monitoring violation. NR 809.565(1)(d)(d) Failure to monitor shall be treated as a violation for the entire period covered by the annual average where compliance is based on a running annual average of monthly or quarterly samples or averages and the water supplier’s failure to monitor makes it impossible to determine compliance with MCLs or MRDLs. NR 809.565(1)(e)(e) Water suppliers may use only data collected under the provisions of this subchapter NR 809.565(2)(2) Monitoring frequency and location for TTHMs and HAA5s. Water suppliers shall monitor at the following frequency and locations for TTHMs and HAA5 disinfection byproducts: NR 809.565(2)(a)1.1. Water suppliers for public water systems serving at least 10,000 persons which are supplied by a surface water source or by a groundwater source under the direct influence of surface water shall collect and have analyzed 4 water samples per quarter per treatment plant. NR 809.565(2)(a)1.a.a. At least 25% of all samples collected each quarter at each treatment plant shall be at locations representing the maximum residence time in the public water system. NR 809.565(2)(a)1.b.b. The remaining samples shall be taken in the distribution system at locations representing at least average residence time in the public water system and representative of the entire distribution system, taking into account the number of people served, different sources of water and different treatment methods. NR 809.565(2)(a)2.2. Water suppliers for public water systems serving from 500 to 9,999 persons which are supplied by a surface water source or by a groundwater source under the direct influence of surface water shall collect and have analyzed one water sample per quarter per treatment plant. The samples shall be collected at locations representing the maximum residence time of water in the public water system. NR 809.565(2)(a)3.3. Water suppliers for public water systems serving fewer than 500 people which are supplied by a surface water source or by a groundwater source under the direct influence of surface water shall collect one sample per treatment plant annually. The samples shall be collected during the month with the warmest water temperature at locations representing the maximum residence time in the public water system. NR 809.565(2)(a)4.4. Water suppliers for public water systems using chemical disinfection, using only groundwater not under the direct influence of surface water, and serving at least 10,000 people shall collect one sample per treatment plant per quarter. The sample or samples shall be collected at the location representing the maximum residence time in the public water system. NR 809.565(2)(a)5.5. Water suppliers for public water systems using chemical disinfection, using only groundwater not under the direct influence of surface water, and serving fewer than 10,000 people shall collect one sample per treatment plant annually. The sample shall be collected during the month with the warmest water temperature, at locations representing the maximum residence time, in the public water system. NR 809.565(2)(b)(b) Monitoring after exceeding an MCL. If a sample or the average of samples, if more than one sample is taken, exceeds the MCL for TTHMs or HAA5 disinfection byproducts, the water supplier shall collect quarterly samples until the public water system meets the requirements of reduced monitoring in par. (c). NR 809.565(2)(c)(c) Reduced monitoring. Water suppliers may reduce monitoring for TTHMs and HAA5s as follows: NR 809.565(2)(c)1.1. Water suppliers for surface water systems or groundwater systems under the direct influence of surface water with an annual average of TTHM of < 0.040 mg/L and HAA5 =0.030 mg/L with an annual average TOC concentration of < 4.0 mg/L, before any treatment may reduce monitoring to the following: NR 809.565(2)(c)1.a.a. Water suppliers for a public water system serving at least 10,000 people may reduce monitoring to one sample per quarter per treatment plant so long as the sample is taken at a location representing maximum residence time in the public water system. NR 809.565(2)(c)1.b.b. Water suppliers for a public water system serving from 500 to 9,999 people may reduce monitoring to one sample per year per treatment plant so long as the sample is taken at a location representing maximum residence time in the public water system during the month of warmest water temperature. NR 809.565(2)(c)1.c.c. A water supplier for a public water system serving less than 500 people may not reduce monitoring to less than one sample during the month of warmest water temperature per treatment plant per year. NR 809.565(2)(c)2.2. A water supplier for a public water system using only groundwater not under the direct influence of surface water using chemical disinfection with an annual average of TTHM of < 0.040 mg/L and HAA5 < 0.030 mg/L may reduce sampling to the following: NR 809.565(2)(c)2.a.a. A water supplier for a public water system serving at least 10,000 people may reduce monitoring to one sample per year per treatment plant during the month of warmest water temperature at a location representing maximum residence time in the public water system. NR 809.565(2)(c)2.b.b. A water supplier for a public water system serving fewer than 10,000 people may reduce monitoring to one sample per treatment plant per 3 year monitoring cycle during the month of warmest water temperature at a location representing maximum residence time in the public water system. The reduced monitoring will begin on January 1 following the quarter in which the public water system first qualifies for reduced monitoring. NR 809.565(2)(c)2m.2m. To qualify for reduced monitoring for TTHM and HAA5 under this paragraph, water suppliers for surface water systems or groundwater systems under the direct influence of surface water not monitoring under the provisions of sub. (5) shall take monthly TOC samples every 30 days at a location prior to any treatment, beginning April 1, 2008, or earlier, if specified by the department. In addition to meeting other criteria for reduced monitoring in this paragraph, the source water TOC running annual average shall be =4.0 mg/L, based on the most recent four quarters of monitoring, on a continuing basis at each treatment plant to reduce or remain on reduced monitoring for TTHM and HAA5. Once qualified for reduced monitoring for TTHM and HAA5 under this paragraph, a system may reduce source water TOC monitoring to quarterly TOC samples taken every 90 days at a location prior to any treatment. NR 809.565(2)(c)3.3. Public water systems on a reduced monitoring schedule may remain on that reduced schedule as long as the average of all samples taken in the year, for public water systems which shall monitor quarterly, or the result of the sample, for public water systems which shall monitor no more frequently than annually, is no more than 0.060 mg/L and 0.045 mg/L for TTHMs and HAA5, respectively. A water supplier for a public water systems that do not meet these levels shall resume monitoring at the frequency identified in par. (a) in the quarter immediately following the quarter in which the public water system exceeds 0.060 mg/L and 0.045 mg/L for TTHMs and HAA5, respectively. NR 809.565(2)(d)(d) Return to routine monitoring. The department may return a public water system to routine monitoring at the department’s discretion.
