NR 809.567(3)(b) (b) Water supplier for public water systems monitored for chlorine dioxide under the requirements of s. NR 809.565 (4) (b) shall report all of the following information:

NR 809.567(3)(b)1. 1. The dates, results and locations of samples taken during the last quarter.

NR 809.567(3)(b)2. 2. Whether the MRDL was exceeded, as determined according to s. NR 809.566 (3) (b).

NR 809.567(3)(b)3. 3. Whether the MRDL was exceeded in any 2 consecutive daily samples and whether the resulting violation was acute or nonacute as determined according to s. NR 809.566 (3) (b).

NR 809.567(4) (4) Disinfection byproduct precursors, enhanced coagulation or enhanced softening treatment systems. Water supplier for public water systems containing disinfection byproduct precursors or using enhanced coagulation or enhanced softening, shall report the information specified in the following:

NR 809.567(4)(a) (a) Water supplier for public water systems monitored monthly or quarterly for TOC under the requirements of s. NR 809.565 (5) and required to meet the enhanced coagulation or enhanced softening requirements in s. NR 809.569 (1) (b) or (c) shall report all of the following:

NR 809.567(4)(a)1. 1. The number of paired samples of source water and treated water, both prior to continuous disinfection, taken during the last quarter.

NR 809.567(4)(a)2. 2. The location, date and result of each paired sample and associated alkalinity taken during the last quarter.

NR 809.567(4)(a)3. 3. For each month in the reporting period that paired samples were taken, the arithmetic average of the percent reduction of TOC for each paired sample and the required TOC percent removal.

NR 809.567(4)(a)4. 4. Calculations for determining compliance with the TOC percent removal requirements, as provided in s. NR 809.569 (3).

NR 809.567(4)(a)5. 5. Whether the public water system is in compliance with the enhanced coagulation or enhanced softening percent removal requirements in s. NR 809.569 (1) for the last 4 quarters.

NR 809.567(4)(b) (b) Water supplier for public water systems monitored monthly or quarterly for TOC under the requirements of s. NR 809.565 (5) and meeting one or more of the alternative compliance criteria in s. NR 809.569 (2) (b) or (c) shall report all of the following:

NR 809.567(4)(b)1. 1. The alternative compliance criterion that the water supplier for the public water system is using.

NR 809.567(4)(b)2. 2. The number of paired samples taken during the last quarter.

NR 809.567(4)(b)3. 3. The location, date and result of each paired sample and associated alkalinity taken during the last quarter.

NR 809.567(4)(b)4. 4. The running annual arithmetic average based on monthly averages or quarterly samples of source water TOC for public water systems meeting a criterion in s. NR 809.569 (2) (b) 1. and 3. or of treated water TOC for public water systems meeting the criterion in s. NR 809.569 (2) (b) 2.

NR 809.567(4)(b)5. 5. The running annual arithmetic average based on monthly averages or quarterly samples of source water SUVA for public water systems meeting the criterion in s. NR 809.569 (2) (b) 6. or of treated water SUVA for public water systems meeting the criterion in s. NR 809.569 (2) (b) 7.

NR 809.567(4)(b)6. 6. The running annual average of source water alkalinity for public water systems meeting the criterion in s. NR 809.569 (2) (b) 3. and 4. and of treated water alkalinity for public water systems meeting the criterion in s. NR 809.569 (2) (c) 1.

NR 809.567(4)(b)7. 7. The running annual average for both TTHM and HAA5 for public water systems meeting the criterion in s. NR 809.569 (2) (b) 3., 4., and 5.

NR 809.567(4)(b)8. 8. The running annual average of the amount of magnesium hardness removal (as CaCO3 mg/L) for public water systems meeting the criterion in s. NR 809.567 (2) (c) 2.

NR 809.567(4)(b)9. 9. Whether the public water system is in compliance with the particular alternative compliance criterion in s. NR 809.569 (2) (b) and (c).

NR 809.567 History History: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.

NR 809.569 NR 809.569 Treatment technique for control of disinfection byproduct (DBP) precursors. For public water systems using conventional treatment which are supplied by a surface water source or by a groundwater source under the direct influence of surface water, the department identifies enhanced coagulation or enhanced softening as treatment techniques to control the level of disinfection byproduct precursors in drinking water and distribution systems. Treatment technique requirements for DBP precursors shall comply with the following:

NR 809.569(1) (1) Enhanced coagulation and enhanced softening performance requirements.

NR 809.569(1)(a) (a) Public water systems using enhanced coagulation or enhanced softening shall achieve the percent reduction of TOC specified in par. (b) between the source water and the combined filter effluent, unless the department approves the water supplier’s request for alternate minimum TOC removal (Step 2) requirements under par. (c).

NR 809.569(1)(b) (b) Required Step 1 TOC reductions, indicated in Table V, are based upon specified source water parameters measured in accordance with s. NR 809.563 (6). Public water systems practicing softening are required to meet the Step 1 TOC reductions in the far-right column, source water alkalinity >120 mg/L, for the specified source water TOC:

Table V

Step 1 Required Removal of TOC by Enhanced Coagulation and Enhanced Softening for Surface Water Systems Using Conventional Treatment

NR 809.569(1)(b)1. 1. Public water systems meeting at least one of the conditions in sub. (2) (b) 1. to 7. are not required to operate with enhanced coagulation.