35 Ill. Adm. Code 203.117
Dispersion Enhancement Techniques
Section 203
Section 203.117 Dispersion
Enhancement Techniques
"Dispersion Enhancement
Techniques" mean so much of the stack height of any source as exceeds good
engineering practice or any other dispersion technique, determined by
regulations at 40 CFR 51.100 (1987) (no future amendments or editions are included).