327 IAC 15-6-7.3 - Monitoring requirements

Current through March 30, 2022

Authority: IC 13-14-8; IC 13-15-1-2; IC 13-15-2; IC 13-18-3; IC 13-18-4

Affected: IC 13-12-3-1; IC 13-18-1

Sec. 7.3.

(a) Monitoring requirements shall be as follows:
(1) Each discharge outfall identified in section 5(4) of this rule, or representative discharge outfall identified in section 5(5) of this rule, composed entirely of storm water and allowable nonstorm water run-off, shall be monitored as follows:

Parameter Units Sample Type Frequency
Oil and grease mg/l grab Annual
CBOD5 (Carbonaceous biochemical oxygen demand) mg/l grab Annual
COD (Chemical oxygen demand) mg/l grab Annual
TSS (Total suspended solids) mg/l grab Annual
TKN (Total Kjeldahl nitrogen) mg/l grab Annual
Total phosphorous mg/l grab Annual
pH s.u. grab Annual
Nitrate plus nitrite nitrogen mg/l grab Annual
(2) Each discharge outfall subject to subdivision (1) shall be monitored for any pollutant attributable to a facility's industrial activity that is reasonably expected to be present in the discharge, as well as for any other pollutant that has the potential to be present in a storm water discharge as requested by the commissioner.
(3) Within one (1) year of the original or renewal NOI letter submittal and prior to implementation of the SWP3, a permittee regulated under this rule shall sample and analyze the discharge from the outfall identified in the approved NOI letter. The monitoring data taken from this first year event shall be used by the permittee as an aid in developing and implementing the SWP3. Subsequent annual sampling data shall be used to verify the effectiveness of the SWP3 and will aid the permittee with revising the SWP3 and implementation of additional BMPs, as necessary.
(4) The commissioner may require a permittee to sample additional storm events beyond the required five (5) annual events upon finding reasonable cause. The commissioner shall notify the facility in writing that additional sampling is required.
(5) A grab sample must be collected during the first thirty (30) minutes of discharge at the storm water outfalls identified in the NOI letter or as soon thereafter as practicable.
(6) The pH measurement must be taken at the time the grab sample is collected and by using a pH meter that has been properly calibrated according to manufacturer's specifications and provides results displayed in numeric units. A color comparison analysis for pH is not acceptable.
(7) There shall be a minimum of three (3) months between reported sampling events.
(8) Samples must be taken at a point representative of the discharge but prior to entry into surface waters of the state or a municipal separate storm sewer conveyance unless an alternative location has been granted by the commissioner. For discharges that flow through on-site detention basins, samples shall be taken at a point representative of the discharge from the basin.
(9) All samples must be collected from a discharge resulting from a measurable storm event at least seventy-two (72) hours from the previous measurable storm event. Documentation of weather conditions that prevent sampling as described in this subsection must be provided to the commissioner.
(10) The analytical and sampling methods used must meet the requirements of 327 IAC 5-2-13(d)(1) and 327 IAC 5-2-13(d)(2) for quality assurance and quality control.
(11) Run-off events resulting from snow or ice melt should not be sampled and shall not be used to meet the minimum annual monitoring requirements.
(b) Reporting requirements shall be as follows:
(1) All samples must be reported as a value of concentration or loading.
(2) For each measurement or sample taken under this rule, the permittee shall record and submit the following information to the commissioner:
(A) The exact place, date, and time of the start of the discharge, the duration of the storm event sampled, a measurement of the rainfall in inches, and time of sampling.
(B) The duration between the storm event sampled and the end of the previous measurable storm event.
(C) The individual who performed the sampling or measurements.
(D) The dates the analyses were performed.
(E) The individual who performed the analyses.
(F) The analytical techniques or methods used.
(G) The results of all required analyses and measurements.
(H) A complete copy of the laboratory report, including chain-of-custody.
(3) All records and information resulting from the monitoring activities required under this rule, including all records of analyses performed and calibration and maintenance of instrumentation, must be retained for a minimum of either one (1) year following the date on an NOT letter, three (3) years following the expiration of the facility's permit, or longer if requested by the commissioner. As applicable, the records for calibration and maintenance of instrumentation can be maintained at an off-site laboratory but must be available to the commissioner upon request. All calibration and maintenance records for on-site instruments, such as pH meters, used by a facility for compliance with this rule must be documented and either contained in, or have the on-site record keeping location referenced in, the SWP3.
(4) A permittee regulated under this rule shall submit sampling data results to the commissioner at the address specified in section 8.5 of this rule within thirty (30) days after laboratory analyses have been completed.
(5) A permittee regulated under this rule that has a discharge that enters a regulated municipal separate storm sewer conveyance shall also submit a copy of the sampling data results to the operator of the regulated municipal system conveyance upon request.
(6) If a permittee regulated under this rule monitors a pollutant more frequently than required under this rule, using analytical methods referenced in subsection (a)(10), the results of such monitoring must be reported as additional information in the annual report. Such increased frequency must also be indicated in the report.


327 IAC 15-6-7.3
Water Pollution Control Board; 327 IAC 15-6-7.3; filed Oct 27, 2003, 10:15 a.m.: 27 IR 857; errata filed Feb 4, 2004, 1:45 p.m.: 27 IR 2285; readopted filed Nov 21, 2007, 1:16 p.m.: 20071219-IR-327070553BFA Readopted filed Jul 29, 2013, 9:21 a.m.: 20130828-IR-327130176BFA; readopted filed Jun 14, 2019, 1:59 p.m.: 20190710-IR-327190246BFA

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