Georgia Department of Natural Resources
NPDES Industrial Storm Water General Permits
2 Martin Luther King Jr. Drive, Suite 1152 East Tower
Atlanta, GA 30334
GNPDES General Permit No. GAR050000 for Storm Water Discharges Associated with Industrial Activity (2012 IGP) effective June 1, 2012 through May 31. 2017.
6.1.3 Measurable Storm Events
188.8.131.52 All required monitoring must be performed on a storm event that is greater than 0.1 inch of rainfall (measurable storm event) that results in an actual discharge from the facility that follows the preceding measurable storm event by at least 72 hours. In the case of snowmelt, the monitoring must be performed at a time when a measurable discharge occurs at the facility.
Magnitude: greater than 0.1 inches
Interval Between Storms: at least 72 hours from the previously measurable event