R 325.10313 Criteria for water supplies using POE, or POU, or both.

Rule 313. (1) Community and noncommunity water supplies shall not use point-of-use devices (POU) or point-of-entry devices (POE) except as required by the department under R 325.10308b or under all of the following provisions with department approval: (a) Community water supplies may use POE to comply with the maximum contaminant level or treatment technique for organic, inorganic, and radiological contaminants. (b) Noncommunity water supplies may use POU, or POE, or both, to comply with maximum contaminant levels or treatment techniques for organic and inorganic contaminants. (c) An alternative source of water that meets state drinking water standards is not available. (2) Supplies that use POU or POE, or both, shall meet all of the following requirements: (a) The supply shall operate and maintain the POU, or POE, or both. (b) Before POU, or POE, or both, are installed, the supply shall obtain department approval of a monitoring plan that ensures that the devices provide health protection equivalent to that provided by central water treatment. If the POU, or POE, or both, are being used to comply with maximum contaminant levels or treatment techniques, then "equivalent" means that the water must meet all state drinking water standards and must be of acceptable quality similar to water distributed by a well-operated central treatment plant. At a minimum, the monitoring plan must include all of the following: (i) Contaminants and parameters to be analyzed. (ii) Physical measurements and observations, such as total flow treated and mechanical condition of the treatment equipment. (iii) Location of sampling sites. (iv) Frequency of sampling. Approximately 10% of the treatment units must be sampled at regular intervals so that all the POE or POU are monitored at least as frequently as required in part 7 for a particular contaminant. For example, for a contaminant that is required to be sampled every 3 years, 10% of the POE or POU must be monitored quarterly so that in 3 years time all of the POE or POU have been monitored. The department may approve an alternate frequency that better represents the rate of degradation of the POE or POU. (c) Before POU, or POE, or both, are installed, the supply shall obtain department approval of a technology plan that ensures that effective technology is applied and that the microbiological safety of the water is maintained at all times. At a minimum, the technology plan must include all of the following: (i) The POU, or POE, or both, must be equipped with mechanical warnings to ensure that customers are automatically notified of operational problems. (ii) If a specific type of POU or POE has been independently certified to comply with the maximum contaminant level or treatment technique in accordance with the American National Standards Institute/National Sanitation Foundation standards 44, 53, 58, or 62, as adopted by reference in R 325.10112, then individual units of that type must be used to comply with the maximum contaminant level or treatment technique. A supply may use an alternate type of POU or POE if the supply demonstrates to the department, using pilot plant studies or other means, that the alternative POU or POE consistently complies with the maximum contaminant level or treatment technique and the department approves the use of the POU or POE. (iii) The design and application of the POU, or POE, or both, must consider the potential for increasing concentrations of heterotrophic bacteria in water treated with activated carbon. Frequent backwashing, post-contactor disinfection, and heterotrophic plate count monitoring may ensure that the microbiological safety of the water is not compromised. (d) The supply shall demonstrate that buildings connected to the system have sufficient POU, or POE, or both, that are properly installed, maintained, and monitored such that all customers are protected. (e) If the POU, or POE, or both, are used to meet an MCL or treatment technique, then the supply shall replace or repair the POU or POE when the contaminant for which the device is intended to control is above the maximum contaminant level in a confirmed sample. (3) Compliance with the maximum contaminant level must be determined based on the analytical results obtained at each POU or POE, also known as the "sampling point". The compliance determination must be made under R 325.10604b(2) for volatile organic contaminants, R 325.10604c(2) for inorganic contaminants, R 325.10604d(2) for synthetic organic chemicals, or R 325.10604g(2) for per- and polyfluoroalkyl substances. (4) Supplies that violate the MCL shall notify the department under part 7 of these rules and shall notify the public under part 4 of these rules. The supply may limit the distribution of the public notice to only persons served by the POU or POE that is out of compliance.