Illinois Administrative Code
Title 35 - ENVIRONMENTAL PROTECTION
Part 501 - GENERAL PROVISIONS
Subpart B - DEFINITIONS AND INCORPORATIONS
Section 501.380 - Water Pollution

The alteration of the physical, thermal, chemical, biological, or radioactive properties of any waters of the State, or the discharge of any contaminant into any waters of the State, as will or is likely to create a nuisance or render those waters harmful or detrimental or injurious to public health, safety, or welfare, to domestic, commercial, industrial, agricultural, recreational, or other legitimate uses, or to humans, livestock, wild animals, birds, or fish or other aquatic life.