35 Ill. Adm. Code 306.402
Restricted Status
Section 306
Section 306.402 Restricted
Status
a) Restricted status means the Agency's determination that a
sewer has reached hydraulic capacity or a sewage treatment plant has reached
design capacity and, as a result, additional sewer connection permits may no
longer be issued without causing a violation of the Act or regulations.
b) The
Agency may place a sewage treatment plant on Restricted Status when any of the
following conditions exist, as shown by Agency field inspections, operational
reports, records of permits issued, or other information:
1) Hydraulic
overloading of the treatment plant as determined by a comparison of the
permitted design capacity of the plant with the actual average monthly flows
measured at the plant during the three low-flow months in the preceding
12-month period, adjusted to include all outstanding (permitted but not
connected) permits issued by the Agency, or other information on hydraulic
loading of the plant available to the Agency (i.e., water pumpage, recent
development, demographic and meteorological data, etc.);
2) Organic
overloading of the treatment plant as determined by the comparison of the
permitted design capacity of the plant with the actual average monthly loadings
in the preceding 12-month period, adjusted to include all outstanding
(permitted but not connected) permits issued by the Agency, or other
information on organic loading of the treatment plant available to the Agency
(i.e., water pumpage, recent development, demographic and meteorological data,
etc.);
3) Continuing
violation of effluent limitations established by the treatment plant's National
Pollutant Discharge Elimination System (NPDES) permit. Determining a violation
of effluent limitations must be made according to the sampling, testing, and
averaging procedures specified in the NPDES permit;
4) Operational
neglect resulting in frequent bypassing of any treatment unit or units; or
5) An
Illinois Pollution Control Board decision finding a violation of Section 12(a)
of the Environmental Protection Act [415 ILCS 5/12(a)].
c) The
Agency may place sanitary sewers and lift stations on Restricted Status to
prevent overflows as prohibited under Subpart C. Restricted Status may be
imposed upon confirming overflows in the form of basement backups, overflows of
sanitary sewer manholes, or sanitary sewer overflow devices.
d) All combined
and sanitary sewers and lift stations are subject to Restricted Status when
they become hydraulically overloaded, meaning unable to accommodate the
following flows:
1) Combined
sewers and lift stations serving combined sewers must be able to handle 350
percent of the average daily flow (based on best available information) before
overflowing.
2) Interceptors
serving both combined sewers and sanitary sewers must be able to accommodate
250 percent of the average daily dry weather flow (based on best available
information) from the sanitary sewers tributary to them and 350 percent of the
average daily dry weather flow from the combined sewers tributary to them
before overflowing.