Mich. Admin. Code R. 325.10719h

Current through Vol. 24-21, December 1, 2024

Section R. 325.10719h - Disinfection byproducts; routine monitoring

Rule 719h.

(1) A community or nontransient noncommunity water supply that is subject to disinfection byproducts requirements of R 325.10610d shall monitor at the location or locations and dates identified in the monitoring plan in R 325.10719e(5), updated as required by R 325.10719i. These community and noncommunity water supplies are also considered "water supplies" or "supplies" in this rule and R 325.10719i to R 325.10719n.

(2) The supply shall monitor at least the number of locations identified in the following table:

Source Water Type	Population size category	Monitoring Frequency 1	Distribution system monitoring locations total per monitoring period 2
Subpart H	less than 500	per year	2
Subpart H	500 to 3,300	per quarter	2
Subpart H	3,301 to 9,999	per quarter	2
Subpart H	10,000 to 49,999	per quarter	4
Subpart H	50,000 to 249,999	per quarter	8
Subpart H	250,000 to 999,999	per quarter	12
Subpart H	1,000,000 to 4,999,999	per quarter	16
Subpart H	greater than or equal to 5,000,000	per quarter	20
Groundwater	less than 500	per year	2
Groundwater	500 to 9,999	per year	2
Groundwater	10,000 to 99,999	per quarter	4
Groundwater	100,000 to 499,999	per quarter	6
Groundwater	greater than or equal to 500,000	per quarter	8

¹ All supplies shall monitor during month of highest DBP concentrations.

² Supplies on quarterly monitoring shall take dual sample sets every 90 days at each monitoring location, except for subpart H supplies serving 500 to 3,300. Groundwater supplies serving 500-9,999 on annual monitoring shall take dual sample sets at each monitoring location. All other supplies on annual monitoring and subpart H supplies serving 500 to 3,300 shall take individual TTHM and HAA5 samples (instead of a dual sample set) at the locations with the highest TTHM and HAA5 concentrations, respectively. For supplies serving fewer than 500 people, only 1 location with a dual sample set per monitoring period is needed if the highest TTHM and HAA5 concentrations occur at the same location and month.

(3) An undisinfected supply that begins using a disinfectant other than UV light shall consult with the department to identify compliance monitoring locations for TTHM and HAA5 under R 325.10610d and R 325.10719h to R 325.10719n. The supply shall then develop a monitoring plan under R 325.10719i th at includes those monitoring locations.

Mich. Admin. Code R. 325.10719h

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