Indiana Administrative Code
Title 327 - WATER POLLUTION CONTROL DIVISION
Article 8 - PUBLIC WATER SUPPLY
Rule 2.5 - Disinfectants and Disinfection
Section 2.5-12 - Routine monitoring; stage 2 disinfection byproducts requirements
Current through September 18, 2024
Authority: IC 13-13-5; IC 13-14-8-7; IC 13-14-9; IC 13-18-3-2; IC 13-18-16
Affected: IC 13-18-3-11
Sec. 12.
(a) The following are the routine monitoring requirements for a PWS to comply with section 11 of this rule, this section, and sections 13 through 20 of this rule:
if either requires other locations or additional locations after review of the PWS's IDSE report.
Table 12 | |||
Source Water Type | Population Size Category | Monitoring Frequency1 | Distribution System Monitoring Locations Total per Monitoring Period2 |
Subpart H | < 500 | per year | 2 |
500-3,300 | per quarter | 2 | |
3,301-9,999 | per quarter | 2 | |
10,000-49,999 | per quarter | 4 | |
50,000-249,999 | per quarter | 8 | |
250,000-999,999 | per quarter | 12 | |
1,000,000-4,999,999 | per quarter | 16 | |
> 5,000,000 | per quarter | 20 | |
Ground water | < 500 | per year | 2 |
500-9,999 | per year | 2 | |
10,000-99,999 | per quarter | 4 | |
100,000-499,999 | per quarter | 6 | |
> 500,000 | per quarter | 8 | |
1 All systems must monitor during month of highest DBP concentrations. | |||
2 Systems on quarterly monitoring must take dual sample sets every 90 days at each monitoring location, except for Subpart H systems serving 500-3,300. Ground water systems serving 500-9,999 on annual monitoring must take dual sample sets at each monitoring location. All other systems on annual monitoring and Subpart H systems serving 500-3,300 are required to take individual TTHM and HAA5 samples (instead of a dual sample set) at the locations with the highest TTHM and HAA5 concentrations, respectively. For systems serving fewer than 500 people, only one 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. |
(b) A PWS shall use analytical methods approved under section 5 of this rule for TTHM and HAA5 analyses in section 11 of this rule, this section, and sections 13 through 20 of this rule. Analyses must be conducted by laboratories that have received certification by EPA or the commissioner as specified in section 5 of this rule.