Section NR 809.54 - General requirements for the control of lead and copper(1) APPLICABILITY. (a) The requirements of this subchapter constitute the primary drinking water regulations for lead and copper. Unless otherwise indicated, each of the provisions of this subchapter applies to community water systems and non-transient, non-community water systems.(2) SCOPE. These regulations establish a treatment technique that includes requirements for corrosion control treatment, source water treatment, lead service line replacement and public education. These requirements are triggered, in some cases, by lead and copper action levels measured in samples collected at consumers' taps.(3) LEAD AND COPPER ACTION LEVELS.(a) The lead action level is exceeded if the concentration of lead in more than 10% of tap water samples collected during any monitoring period conducted in accordance with s. NR 809.547 is greater than 0.015 mg/L, which means if the "90th percentile" lead level is greater than 0.015 mg/L.(b) The copper action level is exceeded if the concentration of copper in more than 10% of tap water samples collected during any monitoring period conducted in accordance with s. NR 809.547 is greater than 1.3 mg/L, which means if the "90th percentile" copper level is greater than 1.3 mg/L.(c) The 90th percentile lead and copper levels shall be computed as follows: 1. The results of all lead or copper samples taken during a monitoring period shall be placed in ascending order from the sample with the lowest concentration to the sample with the highest concentration. Each sampling result shall be assigned a number, ascending by single integers beginning with the number 1 for the sample with the lowest contaminant level. The number assigned to the sample with the highest contaminant level shall be equal to the total number of samples taken.2. The number of samples taken during the monitoring period shall be multiplied by 0.9.3. The contaminant concentration in the numbered sample yielded by the calculation in subd. 2. is the 90th percentile contaminant level.4. For water public water systems serving fewer than 100 people that are sampled at a rate of 5 samples per monitoring period, the 90th percentile is computed by taking the average of the highest and second highest concentrations.5. For a public water system that has been allowed by the department to be sampled at a rate of fewer than five samples in accordance with federal rule 40 CFR 141.86(c), the sample result with the highest concentration is considered the 90th percentile value.(4) CORROSION CONTROL TREATMENT REQUIREMENTS.(a) All water suppliers shall install and operate optimal corrosion control treatment as defined in s. NR 809.04.(b) Any public water system that complies with the applicable corrosion control treatment requirements specified by the department under ss. NR 809.542 and 809.543 shall be deemed in compliance with the treatment requirement contained in par. (a).(5) SOURCE WATER TREATMENT REQUIREMENTS. Any water supplier for a public water system exceeding the lead or copper action level shall implement all applicable source water treatment requirements specified by the department under s. NR 809.544.(6) LEAD SERVICE LINE REPLACEMENT REQUIREMENTS. Any water supplier for a public water system exceeding the lead action level after implementation of applicable corrosion control and source water treatment requirements shall complete the lead service line replacement requirements contained in s. NR 809.545.(7) PUBLIC EDUCATION REQUIREMENTS. Any water supplier for a public water system exceeding the lead action level shall implement the public education requirements contained in s. NR 809.546. Any water supplier for a public water system exceeding the copper action level shall annually provide public education on the health effects of copper using language in Appendix B to subch. VII, and information on reducing exposure to copper in drinking water similar to s. NR 809.546.Wis. Admin. Code Department of Natural Resources NR 809.54
CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.Amended by, correction in (3) (c) 5 made under s. 35.17, Stats., Register December 2018 No. 756, eff. 1/1/2019