C-3
Subdivisions- Homeowner Maintenance of Septic Systems
Homeowners must maintain their own septic systems so that disinfection takes place. This usually
involves adding chlorine tablets into their system to disinfect. Most systems require one tablet added to
the system, checking the chlorinator once a month to determine how often to add tablets (depends on
family size). Please see operating procedures for individual septic units or your county health department
for maintenance instructions.
Illinois EPA will work with Stelle Community Association for future compliance with the fecal coliform
standard.
Fecal Coliform Chlorination Exemptions
Waters unsuited to support primary contact uses because of physical, hydrologic or geographic
configuration and are located in areas unlikely to be frequented by the public on a routine basis as
determined by the Agency at 35 Ill. Adm. Code 309.Subpart A, are exempt from the fecal coliform
standard (35 Ill. Adm. Code 302.209 (b)). The facility must demonstrate it is an unprotected water of the
State to obtain a year-round disinfection exemption under 35 Ill. Adm. Code 378.203.
Unprotected waters are not required to comply with the fecal coliforms standards (35 Ill. Adm. Code
378.203). Characteristics of unprotected waters include but are not limited to the following, and waters
must possess one or more of these characteristics to be classified as unprotected waters:
a) Waters with average depths of two feet or less and no pronounced deep pools during the
summer season;
b) Waters containing physical obstacles sufficient to prevent access or primary contact
activities; or
c) Waters with adjacent land uses sufficient to discourage primary contact activities.
To demonstrate the unprotected status of the water, the permitee must assess the water (35 Ill. Adm. Code
378.204). The permittee shall conduct surveys necessary to determine whether affected waters currently
support or have the potential to support primary contact activities. The permitee shall conduct surveys
necessary to determine whether any affected waters which flow through or adjacent to parks or residential
areas have the potential to attract the public and create a risk of incidental or accidental contact. Such
waters are protected by the seasonal fecal coliform standard (limits for the recreational period of May
through October) unless the permittee can demonstrate that access is limited by such impediments as
fences or steep banks.
The Agency must model the die-off of fecal coliform from its discharge to show that at the end of the
unprotected water, the water is meeting the fecal coliform standard. The first order die-off equation and
application of it may be found in 35 Ill. Adm. Code 378 Appendix A through E. The initial fecal coliform
concentration used in the die-off equation is required to be used by the permittee. An average fecal
coliform concentration of over at least 3 months is preferable, but a minimum of 4 samples in 30 days is
acceptable.
