1. (a) A CWS for which a reduction in monitoring for total coliforms has been approved pursuant to Env-Dw 709.06 shall return to standard monthly monitoring by taking the number of samples for total coliforms specified in Env-Dw 709.05(a) the month following the event if:

   1. (1) The CWS:

      1. a. Has implemented a boil order in accordance with Env-Dw 709.19;
      2. b. Triggers one level 2 assessment or 2 level 1 assessments in a rolling 12-month period;
      3. c. Has a treatment technique violation as specified in Env-Dw 709.23;
      4. d. Has 2 bacteria monitoring violations in a rolling 12-month period;
      5. e. Is without a certified operator for the system for more than 30 consecutive days; or
      6. f. Adds a new source.
   2. (2) The department determines that a groundwater source for the CWS is under the direct influence of surface water or otherwise no longer qualifies as a protected water source, for example due to activities or circumstances that makes the source vulnerable to pathogenic contamination; or
   3. (3) The physical configuration of the CWS warrants additional monitoring to accurately determine water quality.
2. (b) If the department determines that any of the criteria listed in (a) above, has been met, the department shall notify the CWS owner in writing of its determination and that Env-Dw 709.07(a) requires the system to return to the monitoring frequency for total coliforms specified in Env-Dw 709.05(a).

Source. #9700, eff 5-1-10; ss by #10771, eff 2-1-15; ss by 14343, eff 8-22-25, EXPIRES: 8-22-35