NR 809.24(2)(2) Best available treatment. The following are the BATs available for achieving compliance with the maximum contaminant level for the volatile organic chemicals listed in sub. (1):

NR 809.24(2)(a)(a) Central treatment using packed tower aeration.

NR 809.24(2)(b)(b) Central treatment using granular activated carbon, except for vinyl chloride and dichloromethane.

NR 809.24(3)(3) Alternative treatment. The department may approve the use of alternative treatment not listed in sub. (2), 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. (1).

NR 809.243(1)(1) Detection limits. For the purposes of this section, detection is defined as >0.0005 mg/l, except for vinyl chloride for which detection is defined as >0.0002 mg/L.

NR 809.243(2)(2) Analytical methods. Analysis for the volatile organic contaminants listed in s. NR 809.24 shall be conducted using the methods prescribed in Table E.

1 Procedures for Methods 502.2, 524.2, and 551.1 are in Methods for the Determination of Organic Compounds in Drinking Water Supplement III, EPA/600/R-95-131, August 1995. These documents are available from the National Technical Information Service (NTIS), U.S. Department of Commerce, 5285 Port Royal Road, Springfield, Virginia 22161. The toll free number is 1-800-553-6847.

2 EPA Method 524.3, Version 1.0. “Measurement of Purgeable Organic Compounds in Water by Capillary Column Gas Chromatography/Mass Spectrometry,” June 2009. EPA 815–B–09–009. Available at http://epa.gov/safewater/methods/analyticalmethods_ogwdw.html.

NR 809.243(3)(3) Sample collection. Samples shall be collected using containers, preservatives 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.

NR 809.243(4)(4) Laboratory certification. Analyses under this section shall only be conducted by laboratories that have received certification under ch. NR 149 or have been approved by EPA.

NR 809.243(5)(5) Laboratory evaluation. Each certified laboratory shall determine the method detection limit (MDL) at which it is capable of detecting VOCs as defined in federal law under 40 CFR, Part 136, Appendix B. The maximum acceptable MDL is 0.0005 mg/L for all VOCs except vinyl chloride, which is 0.0002 mg/L.

NR 809.243 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (1), (2) Table E footnotes, (5) Register March 2016 No. 723, eff. 4-1-16.

NR 809.245(1)(1) General. Water suppliers for community and non-transient non-community water systems shall monitor for the contaminants listed in s. NR 809.24 for purposes of determining compliance with the maximum contaminant levels as follows:

NR 809.245(1)(a)(a) Groundwater sources shall be sampled at every entry point to the distribution system which is representative of each well after treatment. Each sample shall be taken at the same location unless, if approved by the department, conditions make another location more representative of each source, treatment plant, or within the distribution system.

NR 809.245(1)(b)(b) Surface water sources or combined surface water and groundwater sources shall be sampled at each entry point to the distribution system after treatment or at points, if approved by the department, in the distribution system that are more representative of each source after treatment. Each sample shall be taken at the same location unless, if approved by the department, conditions make another location more representative of each source, treatment plant or within the distribution system.

NR 809.245(1)(c)(c) If the public water system draws water from more than one source and the sources are combined before distribution, the public water system shall be sampled at an entry point to the distribution system during periods of normal operating conditions when water representative of all sources is being used.

NR 809.245(1)(d)(d) Water suppliers for new public water systems or public water systems that use a new source of water shall demonstrate compliance with the MCLs specified in s. NR 809.24 in accordance with the requirements in this section. The water supplier shall also comply with the initial sampling frequencies specified by the department to ensure the public water system can demonstrate compliance with the MCLs. Routine and increased monitoring frequencies shall be conducted in accordance with the requirements in this section.

NR 809.245(2)(2) Monitoring frequency for volatile organic contaminants. The frequency of monitoring to determine compliance with the maximum contaminant level for volatile organic contaminants specified in s. NR 809.24 shall be conducted as follows:

NR 809.245(2)(a)(a) Initial monitoring.

NR 809.245(2)(a)1.1. Water suppliers for new community public water systems or community public water systems with new sources shall demonstrate compliance with the MCLs listed under s. NR 809.24 for volatile organic contaminants prior to initiating water service.

NR 809.245(2)(a)2.2. Each water supplier for a community or a non-transient non-community water system shall take 4 consecutive quarterly samples for each VOC contaminant specified in s. NR 809.24, beginning with the first quarter a new source goes into service.

NR 809.245(2)(a)3.3. If the initial monitoring under subds. 1. and 2. for the VOC contaminants listed in s. NR 809.24, did not detect any VOC contaminant, then the water supplier shall take one sample annually.

NR 809.245(2)(b)(b) Routine monitoring. Each water supplier for a community or a non-transient non-community water system shall take annual samples for VOC contaminants specified in s. NR 809.24.