For purposes of this part, the following definitions shall apply unless otherwise specified:

1. (a) “Action level (AL)” means the concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow;
2. (b) “Consumer confidence report (CCR)” means an annual report supplied by a CWS O/O to customers which contains information on the quality of their drinking water;
3. (c) “Customers” means billing units or service connections to which water is delivered by a CWS;

4. (d) “Detected” means the presence of any primary or secondary drinking water contaminant including:

   1. (1) Microbiological contaminants;
   2. (2) Radiological contaminants;
   3. (3) IOC contaminants;
   4. (4) VOC contaminants;
   5. (5) SOC contaminants;
   6. (6) PFAS contaminants; and
   7. (7) Disinfection by-products;
5. (e) “Regulated contaminant” means a contaminant that is subject to a maximum contaminant level (MCL), action level (AL), maximum residual disinfectant level (MRDL), or treatment technique (TT); and
6. (f) “Unregulated contaminant” means a contaminant specified in 40 CFR 141.40.

Source. (See Revision Note at chapter heading for Env-Dw 800) #9730, eff 6-30-10; ss by #12675, eff 1-1-19; amd by #12838, eff 9-30-19