Illinois Administrative Code
Title 35 - ENVIRONMENTAL PROTECTION
Part 611 - PRIMARY DRINKING WATER STANDARDS
Subpart F - MAXIMUM CONTAMINANT LEVELS (MCLs) AND MAXIMUM RESIDUAL DISINFECTANT LEVELS (MRDLs)
Section 611.312 - Maximum Contaminant Levels (MCLs) for Disinfection Byproducts (DBPs)
Current through Register Vol. 48, No. 38, September 20, 2024
a) Bromate and Chlorite. MCLs for bromate and chlorite apply to CWS and NTNCWS suppliers:
Disinfection Byproduct |
MCL (mg/L) |
Bromate |
0.010 |
Chlorite |
1.0 |
Disinfection Byproduct |
Best Available Technology |
Bromate |
Controlling the ozone treatment process to reduce bromate production. |
Chlorite |
Controlling the treatment processes to reduce disinfectant demand and controlling the disinfection treatment processes to reduce disinfectant levels. |
b) TTHM and HAA5
Disinfection Byproduct |
MCL (mg/L) |
Total trihalomethanes (TTHM) |
0.080 |
Haloacetic acids (five) (HAA5) |
0.060 |
Disinfection Byproduct |
Best Available Technology |
Total trihalomethanes (TTHM) and Haloacetic acids (five) (HAA5) |
Enhanced coagulation or enhanced softening, plus GAC10; or nanofiltration with a molecular weight cutoff [LESS THAN OR EQUAL TO] 1000 Daltons; or GAC20 |
Disinfection Byproduct |
Best Available Technology |
Total trihalomethanes (TTHM) and Haloacetic acids (five) (HAA5) |
Any system serving 10,000 or more persons: Improved distribution system and storage tank management to reduce residence time, plus using chloramines for disinfectant residual maintenance; or Any system serving fewer than 10,000 persons: Improved distribution system and storage tank management to reduce residence time. |
BOARD NOTE: This Section derives from 40 CFR 141.64.