NR 809.205(2)(d)2.f.f. Use of PCBs in equipment used in the production, storage or distribution of water such as pumps and transformers.

NR 809.205(2)(e)(e) Waiver conditions and monitoring assessments. As a condition of the waiver under par. (d), the water supplier for a groundwater system shall update the monitoring assessment considering the factors listed under par. (d). Based on this monitoring assessment, the department shall reconfirm that the public water system is non-vulnerable. If the department does not make this reconfirmation within 3 years of the initial determination or each subsequent determination, then the waiver is invalidated and the public water system is required to sample during each compliance period as specified under par. (b).

NR 809.205(6)(6) Monitoring for detected contaminants. If a synthetic organic contaminant listed in s. NR 809.20 is detected, as provided by s. NR 809.203 (1) in any sample, then the water supplier shall monitor quarterly at each entry point which resulted in detection. Quarterly monitoring may be modified by the department as follows:

NR 809.205(6)(a)(a) The department may decrease the quarterly monitoring requirement specified in par. (a) provided it has determined that the public water system is reliably and consistently below the MCL. In no case may the department make this determination unless a groundwater system has been monitored in a minimum of 2 quarters and a surface water system has been monitored in a minimum of 4 quarters.

NR 809.205(6)(b)(b) After the department determines the public water system is reliably and consistently below the MCL, the department may allow the public water system to be monitored annually. Public water systems which are monitored annually shall be monitored during the quarter that previously yielded the highest analytical results.

NR 809.205(6)(c)(c) Water suppliers for public water systems that have 3 consecutive annual samples with no detection of a contaminant may apply to the department for reduced routine monitoring as specified under subs. (1) (c) and (2) (b) or a waiver as specified under subs. (1) (d) and (e) and (2) (c) and (d).

NR 809.205(6)(d)(d) If monitoring results in detection of one or more of certain related contaminants such as heptachlor and heptachlor epoxide, then subsequent monitoring shall analyze for all related contaminants.

NR 809.205(7)(7) Monitoring when an MCL is exceeded. Additional monitoring for synthetic organic contaminants shall be required as follows in order to maintain compliance:

NR 809.205(7)(a)(a) If an organic contaminant listed in s. NR 809.20 is detected at a level exceeding the MCL in any sample, then the water supplier shall begin to take quarterly samples at each entry point which exceeded an MCL.

NR 809.205(7)(b)(b) Public water systems which exceed an MCL listed in s. NR 809.20 as determined by s. NR 809.207 (1) shall be monitored quarterly. After a minimum of 4 quarterly samples show that the public water system is back in compliance and the department determines the public water system is reliably and consistently below the MCL as specified in s. NR 809.207 (1), the public water system shall be monitored at the frequency specified in sub. (6) (b).

NR 809.205(8)(8) Confirmation samples. The department may require a confirmation sample for positive or negative results. If a confirmation sample is required by the department, the result shall be averaged with the first sampling result and the average used for the compliance determination as specified by s. NR 809.207 (1). The department may delete results of obvious sampling errors from this calculation, or may require additional samples to determine whether the result is or is not in error.

NR 809.205(9)(9) Composite sampling. The department may reduce the total number of samples a public water system is required to analyze by allowing the use of compositing. If the department allows compositing, the following composite sampling requirements shall be met:

NR 809.205(9)(a)(a) Composite samples from a maximum of 5 entry points are allowed, if the detection limit of the method used for analysis is less than one-fifth of the MCL. Compositing is only permitted at entry points within a single public water system. Compositing of samples shall be done in the laboratory and analyzed within 14 days of sample collection.

NR 809.205(9)(b)(b) If the concentration in the composite sample detects one or more contaminants listed in s. NR 809.20, then a follow-up sample shall be taken and analyzed for each contaminant detected within 14 days from each entry point included in the composite.

NR 809.205(9)(c)(c) If duplicate aliquots of the original sample taken from each entry point used in the composite are available, the public water system may use these duplicates instead of re-sampling. The duplicate shall be analyzed and the results reported to the department within 14 days of collection.

NR 809.205(10)(10) Increasing monitoring frequency. The department may increase the required monitoring frequency, if necessary, to detect variations within the public water system. Examples of variations include fluctuations in concentration due to seasonal use or changes in the water source.

NR 809.205(11)(11) Designation of sampling times. Each public water system shall be monitored during the month, quarter or year designated by the department within each compliance period.

NR 809.205 HistoryHistory: CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10; CR 15-049: am. (2) (a), (3), (4) (intro.), renum. (4) (a) to (a) (intro.) and am., cr. (4) (a) 1. to 3., am. (4) (b), (5) Register March 2016 No. 723, eff. 4-1-16; CR 21-088: cr. (1g), (1r), am. (2) (intro.), (a), (b), renum. (3), (4), (5) to (2) (c), (d), (e) and, as renumbered, am. (2) (c), (d) (intro.), 1. (intro.), a., (e), am. (6) (c) Register July 2022 No. 799, eff. 8-1-22; correction in (1r) (e) (intro.), (6) (c) made under s. 13.92 (4) (b) 7., Stats., and correction in (2) (d) 1. made under ss. 13.92 (4) (b) 7., and 35.17, Stats., Register July 2022 No. 799.

NR 809.207(1)(a)(a) Compliance with the synthetic organic contaminant MCLs specified in s. NR 809.20 shall be determined based on the analytical results obtained at each entry point. If one entry point is in violation of an MCL, the public water system is in violation of the MCL.

NR 809.207(1)(b)(b) For public water systems which are conducting monitoring more frequently than annual, compliance is determined by a running annual average of all samples taken at each entry point. If the annual average of any entry point is greater than the MCL, then the public water system is out of compliance. If the initial sample or a subsequent sample would cause the annual average to be exceeded, then the public water system is out of compliance immediately.

NR 809.207(1)(c)(c) If monitoring is conducted annually or less frequently, the public water system is out of compliance if the level of a contaminant at any entry point is greater than the MCL. Compliance shall be based on the average value of the initial sample and the confirmation sample.

NR 809.207(1)(d)(d) Any contaminant listed in s. NR 809.20 that is detected shall be quantified. Any sample below the reported method detection limit shall be calculated at zero for the purposes of determining the averages in pars. (b) and (c).

NR 809.207(1)(e)(e) If a public water system fails to collect the required number of samples, compliance shall be based on the total number of samples collected.

NR 809.207(2)(2) Detection of synthetic contaminants not listed in s. NR 809.20 (1). Any detection of a synthetic organic contaminant not listed in s. NR 809.20 (1) shall be reported to the department with the other monitoring reports required under this section. The laboratory shall indicate whether any detected synthetic organic contaminant not listed in s. NR 809.20 (1) has been confirmed or tentatively identified, and when a numerical result is reported, whether the result is quantitative or an estimate.

NR 809.207(3)(3) Use of analytical results. The department may determine compliance or initiate enforcement action based upon analytical results and other information compiled by their sanctioned representatives and agencies.