Mich. Admin. Code R. 325.10610

Current through Vol. 24-19, November 1, 2024

Section R. 325.10610 - MCLs for disinfection byproducts

Rule 610.

(1) Both of the following apply to bromate and chlorite:

(a) The maximum contaminant levels (MCLs) for bromate and chlorite are as follows:

Disinfection byproduct	MCL (mg/l)
Bromate	0.010
Chlorite	1.0

(b) The best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs are as follows:

Disinfection byproduct	Best available technology.
Bromate	Control of ozone treatment process to reduce production of bromate.
Chlorite	Control of treatment processes to reduce disinfectant demand and control of disinfection treatment processes to reduce disinfectant levels.

(2) All of the following apply to total trihalomethanes and haloacetic acids:

(a) The MCLs for TTHM and HAA5 are as follows:

Disinfection byproduct	MCL (mg/L)
Total trihalomethanes (TTHM)	0.080
Haloacetic acids (five) (HAA5)	0.060

(b) For all supplies that disinfect their source water, the best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs under subdivision (a) of this subrule are as follows:

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

(c) The best technology, treatment techniques, or other means available for achieving compliance with the MCLs for TTHM and HAA5 under subdivision (a) of this subrule for consecutive supplies are as follows and applies only to the disinfected water that consecutive supplies buy or otherwise receive.

Disinfection byproduct	Best available technology
Total trihalomethanes (TTHM) and Haloacetic acids (five) (HAA5).	Supplies serving 10,000 or more people: Improved distribution system and storage tank management to reduce residence time, plus the use of chloramines for disinfectant residual maintenance. Supplies serving fewer than 10,000 people: Improved distribution system and storage tank management to reduce residence time

Mich. Admin. Code R. 325.10610

2003 AACS; 2005 AACS; 2009 AACS; 2015 MR 20, Eff. 10/16/2015