35 Ill. Adm. Code 304.105
Violation of Water Quality Standards
Section 304
Section 304.105Â Violation of
Water Quality Standards
In addition to the other
requirements of this Part, effluent must not, alone or in combination with
other sources, cause a violation of any applicable water quality standard.Â
When the Agency finds that a discharge that would comply with effluent
standards in this Part would cause or is causing a violation of water quality standards,
the Agency must take appropriate action under Section 31 or Section 39 of the
Act to require the discharge to meet whatever effluent limits are necessary to
ensure compliance with the water quality standards. When such a violation is
caused by the cumulative effect of more than one source, several sources may be
joined in an enforcement or variance proceeding, and measures for necessary
effluent reductions will be determined based on technical feasibility, economic
reasonableness, and fairness to all dischargers.