35 Ill. Adm. Code 302.306
Fecal Coliform
Section 302
Section 302.306 Fecal
Coliform
Notwithstanding the provisions
of Section 302.209, at no time shall the geometric mean, based on a minimum of
five samples taken within a 30-day period, of fecal coliform exceed 2000 per
100 ml.