35 Ill. Adm. Code 302.505

Fecal Coliform

Last amended: 2023Year: 2026Length: 82 wordsOfficial source
Section 302 Section 302.505  Fecal Coliform Based on a minimum of five samples taken over not more than a 30-day period, fecal coliform must not exceed a geometric mean of 20 per 100 ml in the Open Waters of Lake Michigan as defined in Section 302.501.  The remaining waters of the Lake Michigan Basin must not exceed a geometric mean of 200 per 100 ml, nor may more than 10% of the samples during any 30-day period exceed 400 per 100 ml.