On September 10, EPA issued the administrative order (Order) under section 1431 of the SDWA based on a determination of potential imminent and substantial endangerment due to an E. coli maximum contaminant level exceedance (MCL). A violation of the MCL for E. coli occurs if a system has any combination of a total coliform positive and E. coli positive routine and repeat samples. E. coli can cause symptoms such as diarrhea, nausea, cramps, headaches, and may pose a greater risk for infants, elderly, and immunocompromised individuals.