401 KAR 8:510. Disinfectant residuals, disinfection byproducts and disinfection byproduct precursors.
Samples shall be collected according to the approved sample site plan. A system using chlorine dioxide shall collect one sample daily at the entry point to the distribution system. Additionally, a system shall collect one sample near the first customer, one sample reflecting average residence time and one sample reflecting maximum residence time each month. If a daily sample exceeds the maximum contaminant level of 1.0 mg/L, the system shall collect a three-sample set within 24 hours at the same locations as the required monthly set. Compliance is determined on an average of the samples collected in the distribution system each month. With approval from the Drinking Water Branch, systems may reduce the required monthly monitoring to quarterly, if no daily or monthly exceedances have occurred after one year of monitoring.
