TITLE 35: ENVIRONMENTAL PROTECTION
SUBTITLE C: WATER POLLUTION CHAPTER I: POLLUTION CONTROL BOARD PART 302 WATER QUALITY STANDARDS SECTION 302.658 STREAM FLOW FOR APPLICATION OF HUMAN NONTHRESHOLD CRITERION
Section 302.658 Stream Flow for Application of Human Nonthreshold Criterion
The HNC applies at all times except during periods when flows are less than the harmonic mean flow (Qhm), as determined by:
Qhm = N / SUM(1/Qi)
Where:
(Source: Amended at 47 Ill. Reg. 4437, effective March 23, 2023) |