Table 1 to § 141.202 -Violation Categories and Other Situations Requiring a Tier 1 Public Notice
(1) Violation of the MCL for total coliforms when fecal coliform or E. coli are present in the water distribution system (as specified in § 141.63(b) ), or when the water system fails to test for fecal coliforms or E. coli when any repeat sample tests positive for coliform (as specified in § 141.21(e) ); Violation of the MCL for E. coli (as specified in § 141.63(c) ); |
(2) Violation of the MCL for nitrate, nitrite, or total nitrate and nitrite, as defined in § 141.62 , or when the water system fails to take a confirmation sample within 24 hours of the system's receipt of the first sample showing an exceedance of the nitrate or nitrite MCL, as specified in § 141.23(f)(2) ; |
(3) Exceedance of the nitrate MCL by non-community water systems, where permitted to exceed the MCL by the primacy agency under § 141.11(d) , as required under § 141.209 ; |
(4) Violation of the MRDL for chlorine dioxide, as defined in § 141.65(a) , when one or more samples taken in the distribution system the day following an exceedance of the MRDL at the entrance of the distribution system exceed the MRDL, or when the water system does not take the required samples in the distribution system, as specified in § 141.133(c)(2)(i) ; |
(5) Violation of the turbidity MCL under § 141.13(b) , where the primacy agency determines after consultation that a Tier 1 notice is required or where consultation does not take place within 24 hours after the system learns of the violation; |
(6) Violation of the Surface Water Treatment Rule (SWTR), Interim Enhanced Surface Water Treatment Rule (IESWTR) or Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) treatment technique requirement resulting from a single exceedance of the maximum allowable turbidity limit (as identified in appendix A), where the primacy agency determines after consultation that a Tier 1 notice is required or where consultation does not take place within 24 hours after the system learns of the violation; |
(7) Occurrence of a waterborne disease outbreak, as defined in § 141.2 , or other waterborne emergency (such as a failure or significant interruption in key water treatment processes, a natural disaster that disrupts the water supply or distribution system, or a chemical spill or unexpected loading of possible pathogens into the source water that significantly increases the potential for drinking water contamination); |
(8) Detection of E. coli, enterococci, or coliphage in source water samples as specified in § 141.402(a) and § 141.402(b) ; |
(9) Other violations or situations with significant potential to have serious adverse effects on human health as a result of short-term exposure, as determined by the primacy agency either in its regulations or on a case-by-case basis. |
(10) Exceedance of the Action Level for lead as specified in § 141.80(c) . |
40 C.F.R. §141.202