Industrial General Permit: You’re about to sample, but is it a Qualifying Storm Event?
By your Weather-Ready Nation Ambassadors at Alta Environmental
David Renfrew, QISP/ToR, QSD/P, CPSWQ, PMP
Garth Engelhorn, QISP/ToR, CPSWQ
It is now after January 1 and the recent plethora of rain in California has presented several opportunities to collect samples to comply with California’s Industrial General Stormwater Permit (Order 2014-0057-DWQ) (Permit). However, facility managers and staff should be aware of the 48-hour antecedent no flow condition and what a qualifying storm event (QSE) is. From the Permit (pg. 39):
B.1. A Qualifying Storm Event (QSE) is a precipitation event that:
a. Produces a discharge for at least one drainage area; and,
b. Is preceded by 48 hours with no discharge from any drainage area.
For example, facility staff may be trained to collect samples during working hours, but forget that it may have rained over the weekend, thereby negating the qualifying condition. They need to be aware that samples may not be valid if submitted under this condition. Additionally, samples need to be collected during normal business hours within 4 hours¹ of the beginning of discharge. For reference, Figure 1 shows a flow chart for determining a QSE.
We often recommend that facilities consider conducting a refresher sampling training for their staff in January to get back up to speed with the Permit requirements. Also, since we are in the wet season, we recommend facility sampling staff to get familiar with weather tracking resources. Start reading daily weather forecasts on the national weather service (NWS), watching the evening news, or sign up with a weather alert service. The NWS has several recommendations subscription services for alert messages such as texts or email services (http://www.weather.gov/subscribe). We have recently experimented with IfWeather.com (http://ifweather.com/) and the Darksky apps which appear to be effective but should not be your only resource. We recommend using a variety of weather tracking tools so that you aren’t surprised when it does start raining.
Alta’s experts can provide your business with proactive solutions and BMP recommendations to mitigate the escalating cost of compliance and to prevent future NAL exceedances. If your facility is in ERA Level 1 or headed towards ERA Level 2, Alta’s QISPs (we have seven in house) can provide evaluation and reporting support. To learn more, or for assistance keeping your business in compliance, give us a call at 562-495-5777 or email our Water Resources experts.
David Renfrew, QISP/ToR, QSD, CPSWQ, can be reached via email at email@example.com.
Garth Engelhorn, QISP/ToR, CPSWQ, can be reached via email at firstname.lastname@example.org.
¹If discharge began within 12 hours prior to the start of scheduled facility operating hours, samples can still be collected as a qualifying event. If samples are collected greater than 12 hours after discharge began, the sample event will be considered a non-qualifying storm event.