Section NR 809.118 - Sodium monitoring, reporting and notification requirements(1) GENERAL. The water supplier for a community water system shall collect and analyze one sample per plant at the entry point to the distribution system for the determination of sodium concentration. Samples shall be collected and analyzed annually for public water systems utilizing surface water sources in whole or in part, and at least every 3 years for public water systems utilizing solely groundwater sources. The minimum number of samples required to be taken by the public water system shall be based on the number of plants used by the public water system, except that multiple wells drawing raw water from a single aquifer may, with department approval, be considered one plant for determining the minimum number of samples. The water supplier may be required by the department to collect and analyze water samples for sodium more frequently in locations where the sodium content is variable.(2) DEPARTMENT NOTIFICATION. The water supplier shall report to the department the results of the analyses for sodium concentration within the first 10 days of the month following the month in which the sample results were received or within the first 10 days following the end of the required monitoring period as stipulated by the department, whichever is first. If more than annual sampling is required, the water supplier shall report the average sodium concentration within 10 days of the month following the month in which the analytical results of the last sample used for the annual average was received.(3) HEALTH OFFICIALS NOTIFICATION. The water supplier shall notify appropriate local health officials of the sodium concentration by written notice by direct mail within 3 months of receipt of sample results. A copy of each notice required to be provided by this subsection and a list of health officials notified shall be sent to the department within 10 days of its issuance.(4) ANALYTICAL METHODS. Analyses for sodium shall be performed as prescribed in s. NR 809.113(1), Table A.Wis. Admin. Code Department of Natural Resources NR 809.118
CR 09-073: cr. Register November 2010 No. 659, eff. 12-1-10.A primary maximum contaminant level has not been established for sodium.