A. Any Permittee that conducts the activities listed in Table 3 below and that has surface water discharges shall comply with the effluent limitations prescribed in the sector-specific requirements of Part VII. The Permittee shall identify an effluent monitoring location any place at the facility where industrial activity with an effluent limit occurs. The Permittee shall monitor each effluent monitoring location identified in the SWPPP, in accordance with the procedures outlined in Part VI.B.

ISW effluent monitoring Activities
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Regulated Activity Effluent Limit Monitoring Frequency
Discharges from wet decking storage areas See Sector A 1/year
Runoff from phosphate fertilizer manufacturing facilities that comes into contact with any raw materials, finished product, by-products or waste products (SIC 2874) See Sector C 1/yea
Runoff from asphalt emulsion facilities See Sector D 1/year
Runoff from material storage piles at cement manufacturing facilities See Sector E 1/year
Mine dewatering discharges at construction sand and gravel, or industrial sand mining facilities See Sector J 1/year
Runoff from hazardous waste landfills See Sector K 1/year
Runoff from non-hazardous waste landfills See Sector L 1/year
Runoff from coal storage piles at steam electric generating facilities See Sector O 1/year

B. Required Effluent Monitoring Procedures and Sample Collection Methods

1. One (1) sample shall be collected annually from each effluent monitoring location identified in the SWPPP and analyzed for each required effluent limit parameter specified in Part VII. The sample(s) shall be collected each calendar year the Permittee is authorized to discharge industrial stormwater under this permit.

2. Samples shall be collected during any measurable runoff event at an effluent monitoring location. The sample(s) shall be collected within the first 30 minutes of the measurable runoff event. If it is not possible to collect the sample(s) within the first 30 minutes, the sample(s) shall be collected as soon as practicable after the first 30 minutes and documentation must be included with the Discharge Monitoring Report (DMR) that explains why it was not possible to collect the sample(s) within the first 30 minutes.

3. Samples shall either be taken manually by grab method, or by automated sampling. If automated sampling is used, the device shall either collect one sample during the first 30 minutes of discharge or a series of samples collected throughout the discharge period combined as a composite sample.

4. If the Permittee has determined that an effluent monitoring location and a benchmark monitoring location are at the same location, and the effluent sampling of a pollutant parameter coincides with the sampling of a benchmark pollutant parameter, the Permittee may collect one sample to be analyzed for both purposes.

C. Effluent Limit Exceedances

If sampling by the Permittee indicates a violation of any effluent limitation specified in this permit, the Permittee shall immediately make every effort to verify the violation by collecting additional samples; if appropriate, investigate the cause of the violation and take action to prevent future violations. Violations that are determined to pose a threat to human health or a drinking water supply, or represent a significant risk to the environment shall be immediately reported to the Minnesota Department of Public Safety Duty Officer at 1-800-422-0798 (toll free) or 651-649-5451 (metro area). In addition, the Permittee may also contact the Agency during business hours. Otherwise, the violations and the results of any additional sampling shall be recorded on the next appropriate DMR or report.

D. Effluent Monitoring Data Reporting

1. The effluent monitoring results shall be submitted on a DMR form provided by the Agency. The information must be recorded in the specified areas on the form and in the units specified (Minn. R. 7001.1090, subp. 1(D), Minn. R. 7001.0150, subp. 2(B)).

If during the sampling period, measurable runoff at the effluent monitoring location is such that a sample cannot be acquired (due to weather conditions and/or site soil characteristics); the Permittee shall check the "No Flow" box and note the conditions on the DMR.

2. A DMR shall be submitted for each required effluent monitoring location even if a discharge did not occur during the sampling period. (Minn. R. 7001.0150, subps. 2(B) and 3(H)).

3. The Permittee shall submit the DMR form to the Agency postmarked by the 21st day after the end of the calendar month in which the sample was collected. The Permittee may submit the form using the electronic submittal process or by mailing the form to the following address:


Attn: WQ Submittals Center

520 Lafayette Road North

St. Paul, MN 55155-4194.

4. The Permittee shall immediately submit an amended DMR to the Agency upon discovery by the Permittee or notification by the Agency that the Permittee has submitted an incomplete or incorrect report. The amended report shall contain the missing or corrected data along with a cover letter explaining the circumstances of the incomplete or incorrect report. (Minn. R. 7001.0150, subp. 3(G)).

This page was last edited on 2 April 2013, at 13:24.