WAC 246-292-040. Classification of public water systems

The department shall classify water treatment plants and distribution systems. (1) Water treatment plants. (a) Water treatment plants are classified according to the point system in the ABC " Purification Plant Criteria " publication (October 2007) and are in Table 1. Table 1 Water Treatment Plant Classification Total Points Assigned Water Treatment Plant Classification Less than 31 Class 1 31 to 55 Class 2 56 to 75 Class 3 More than 75 Class 4 Total Points Assigned Water Treatment Plant Classification Less than 31 Class 1 31 to 55 Class 2 56 to 75 Class 3 More than 75 Class 4 (b) The scope of water treatment plant processes include, but are not limited to: (i) Water filtration; (ii) Ion exchange; (iii) Electrodialysis; (iv) Reverse osmosis; or (v) Inorganic contaminant removal. (c) The scope of a water treatment plant does not include unit processes installed for: (i) In-line fluoridation; (ii) In-line chlorination; or (iii) Chemical addition to inhibit corrosion. (2) Distribution systems are classified according to the population served from a public water system's WFI form and are in Table 2. Table 2 Distribution Systems Classification Population Served Distribution System Classification Less than 251 Class S 251 to 1,500 Class 1 1,501 to 15,000 Class 2 15,001 to 50,000 Class 3 More than 50,000 Class 4 Population Served Distribution System Classification Less than 251 Class S 251 to 1,500 Class 1 1,501 to 15,000 Class 2 15,001 to 50,000 Class 3 More than 50,000 Class 4