Section 327 IAC 8-2-8 - Collection of samples for total coliform bacteria testingAuthority: IC 13-13-5; IC 13-14-8-2; IC 13-14-8-7; IC 13-18-3-1; IC 13-18-3-2; IC 13-18-16-8; IC 13-18-16-9
Affected: IC 13-18-2; IC 13-18-16
Sec. 8.
(a) A PWS must collect total coliform samples at sites that are representative of water throughout the distribution system as follows: (1) According to a written sample siting plan approved by the commissioner.(2) Beginning on April I, 2016, each PWS, based on the population served by the PWS, must meet the monitoring requirements of 40 CFR 141, Subpart Y*.(b) The monitoring frequency for total coliforms for a CWS is based on the population served by the CWS and is required through March 31, 2016, as follows unless the commissioner determines that more frequent sampling is appropriate: TOTAL COLIFORM MONITORING FREQUENCY FOR COMMUNITY WATER SYSTEMS
| Population Served | Minimum Number of Samples Per Month |
| 25 to 1,0001 | I |
| 1,001 to 2,500 | 2 |
| 2,501 to 3,300 | 3 |
| 3,301 to 4,100 | 4 |
| 4,101 to 4,900 | 5 |
| 4,901 to 5,800 | 6 |
| 5,801 to 6,700 | 7 |
| 6,701 to 7,600 | 8 |
| 7,601 to 8,500 | 9 |
| 8,501 to 12,900 | 10 |
| 12,901 to 17,200 | 15 |
| 17,201 to 21,500 | 20 |
| 21,501 to 25,000 | 25 |
| 25,001 to 33,000 | 30 |
| 33,001 to 41,000 | 40 |
| 41,001 to 50,000 | 50 |
| 50,001 to 59,000 | 60 |
| 59,001 to 70,000 | 70 |
| 70,001 to 83,000 | 80 |
| 83,001 to 96,000 | 90 |
| 96,001 to 130,000 | 100 |
| 130,001 to 220,000 | 120 |
| 220,001 to 320,000 | 150 |
| 320,001 to 450,000 | 180 |
| 450,001 to 600,000 | 210 |
| 600,001 to 780,000 | 240 |
| 780,001 to 970,000 | 270 |
| 970,001 to 1,230,000 | 300 |
| 1,230,001 to 1,520,000 | 330 |
1 Includes PWSs that have at least fifteen (15) service connections but serve fewer than twenty-five (25) persons.
If a CWS serving twenty-five (25) to one thousand (1,000) persons has no history of total coliform contamination in its current configuration and a sanitary survey conducted in the past five (5) years shows that the CWS is supplied solely by a protected ground water source and is free of sanitary defects, the commissioner may reduce the monitoring frequency specified in this subsection, in writing, except that in no case may the commissioner reduce the monitoring frequency to less than one (1) sample per quarter.
(c) The monitoring frequency for total coliforms for an NCWS is required through March 31, 2016, as follows: (1) An NCWS using only ground water (except ground water under the direct influence of surface water, as defined in section 1(45) of this rule) that serves: (A) one thousand (1,000) or fewer persons: (i) must monitor each calendar quarter that the NCWS provides water to the public; and (ii) may monitor under a reduced frequency allowed in writing by the commissioner if: (AA) a sanitary survey shows that the NCWS is free of sanitary defects; and(BB) not less than once per year monitoring is conducted after June 29, 1994; and(B) more than one thousand (1,000) persons during any month: (i) must monitor at the same frequency as a like-sized CWS, as specified in subsection (b); and (ii) may monitor under a reduced frequency allowed in writing by the commissioner for: (AA) any month the NCWS serves one thousand (1,000) or fewer persons; and(BB) not less than once per year monitoring. For an NCWS using ground water under the direct influence of surface water, subdivision (3) applies.
(2) An NCWS using surface water, in total or in part, must monitor at the same frequency as a like-sized CWS, as specified in subsection (b), regardless of the number of persons it serves.(3) An NCWS using ground water under the direct influence of surface water, as defined in section 1(45) of this rule, must monitor at the: (A) same frequency as a like-sized CWS specified in subsection (b); and(B) frequency under clause (A) beginning six (6) months after the commissioner determines that the ground water is under the direct influence of surface water.(d) The PWS must collect samples through March 31, 2016, at regular time intervals throughout the month, except a PWS that:(1) uses only ground water (except ground water under the direct influence of surface water, as defined in section 1(45) of this rule); and(2) serves four thousand nine hundred (4,900) persons or fewer; may collect all required samples on a single day if they are taken from different sites.(e) Through March 31, 2016, special purpose samples, such as those taken to determine whether disinfection practices are sufficient following pipe placement, replacement, or repair, must not be used to determine compliance with the MCL for total coliforms in section 7 of this rule. Repeat samples taken under section 8.1 of this rule: (1) are not considered special purpose samples; and(2) must be used to determine compliance with the MCL for total coliforms required by section 7 of this rule. Any sample not designated as special purpose before analysis by the laboratory must be used to determine compliance with the MCL for total coliforms in section 7 of this rule.(f) The provisions of this subsection are applicable until all required repeat monitoring under section 8.1 of this rule and fecal coliform or E. coli testing required under section 8.3 of this rule that was initiated by a total coliform positive sample taken before April 1, 2016, is completed as well as analytical method, reporting, record keeping, public notification, and consumer confidence report requirements associated with that monitoring and testing. A total coliform-positive sample invalidated under this subsection does not count towards meeting the minimum monitoring requirements of this section. The total coliform-positive sample may be invalidated only if the following conditions are met: (1) The laboratory establishes that improper sample analysis caused the total coliform-positive result.(2) The commissioner, on the basis of the results of repeat samples collected as required by section 8.1(a) through 8.1(d) of this rule, determines that the total coliform-positive sample resulted from a domestic or other nondistribution system plumbing problem. The commissioner cannot invalidate a:(A) sample on the basis of repeat sample results unless all repeat samples collected: (i) at the same tap as the original total coliform-positive sample are also total coliform-positive; and (ii) within five (5) service connections of the original tap are total coliform-negative; and(B) total coliform-positive sample on the basis of repeat samples if:(i) all the repeat samples are total coliform-negative; or (ii) the PWS has only one (1) service connection.(3) The commissioner has substantial grounds to believe that a total coliform-positive result is due to a circumstance or condition that does not reflect water quality in the distribution system. In this case, the PWS must still collect all repeat samples required by section 8.1(a) through 8.1(d) of this rule and use them to determine compliance with the MCL for total coliforms in section 7 of this rule. To invalidate a total coliform-positive sample under this subsection, the decision must be documented, in writing, and approved and signed by the supervisor of the state official who recommended the decision. The commissioner shall make this document available to U.S. EPA and the public. The written documentation must state the following:(A) The specific cause of the total coliform-positive sample.(B) What action the PWS has taken, or will take, to correct this problem. The commissioner may not invalidate a total coliform-positive sample solely on the grounds that all repeat samples are total coliform-negative.
(4) A laboratory must invalidate a total coliform sample, unless total coliforms are detected, if the sample: (A) produces a turbid culture in the absence of:(i) gas production using an analytical method where gas formation is examined, for example, the multiple-tube fermentation technique; or(ii) an acid reaction in the presence-absence (P-A) coliform test; or(B) exhibits confluent growth or produces colonies too numerous to count with an analytical method using a membrane filter, for example, the membrane filter technique. If a laboratory invalidates a sample because of interference as described in this subdivision, the PWS must collect another sample from the same location as the original sample within twenty-four (24) hours of being notified of the interference problem and have it analyzed for the presence of total coliforms. The PWS must continue to resample within twenty-four (24) hours and have the samples analyzed until it obtains a valid result. The commissioner may waive the twenty-four (24) hour time limit on a case-by-case basis.
(g) Beginning on April 1, 2016, the provisions of 40 CFR 141, Subpart Y*, are applicable, with a PWS required to begin monitoring at the same frequency as the PWS-specific frequency required on March 31, 2016. *This document is incorporated by reference. Copies may be obtained from the Government Publishing Office, www.gpo.gov, or are available for review at the Indiana Department of Environmental Management, Office of Legal Counsel, Indiana Government Center North, 100 North Senate Avenue, Thirteenth Floor, Indianapolis, Indiana 46204.
Water Pollution Control Board; 327 IAC 8-2-8; filed Sep 24, 1987, 3:00 p.m.: 11 IR 707; filed Dec 28, 1990, 5:10 p.m.: 14 IR 1019; errata filed Jan 9, 1991, 2:30 p.m.: 14 IR 1070; errata filed Aug 6, 1991, 3:45 p.m.: 14 IR 2258; filed Apr 12, 1993, 11:00 a.m.: 16 IR 2155; filed Jul 23, 2001, 1:02 p.m.: 24 IR 3965; filed Jul 13, 2007, 11:58 a.m.: 20070808-IR-327060044FRAFiled 1/18/2017, 1:01 p.m.: 20170215-IR-327140059FRA