PADEP Reissues PAG-03 General Permit for Industrial Stormwater

January 18, 2023
Michael Dillon, Esq. and Technical Consultant Will Hitchcock
MGKF Special Alert - Pennsylvania Forecast 2023

On December 24, 2022, PADEP published the renewed PAG-03 general permit for stormwater discharges associated with industrial activity.  The new permit goes into effect on March 24, 2023, and the existing permit expires at that time.  Existing PAG-03 permit holders will need to submit a Notice of Intent (NOI) for coverage under the renewed PAG-03 before March 23, 2023, to maintain permit coverage and authorization to discharge stormwater.  Permittees will also need to update and submit their Preparedness, Prevention, and Contingency (PPC) Plans to the PADEP as part of their NOI packages. 

The NOI includes a requirement to report existing analytical data for the past two years for existing permittees, and to collect new data for pollutants that are considered the cause of impairment to waters receiving stormwater, as PADEP claims this information may be used to determine if the applicant is causing or contributing to the impairment for eligibility purposes.  Applicants for renewal will need to act quickly to determine if additional sampling and analysis needs to be performed prior to the NOI due date of March 23, 2023.

Additionally, the PADEP added a requirement to report details on structural best management practices (BMPs), such as post-construction stormwater management practices, and the amount (in acres) of impervious area each BMP treats.  Permit applicants are encouraged to secure relevant design information for structural BMPs sooner rather than later from their respective design engineers where practicable.

Finally, please note that facilities that are currently exempted from stormwater permitting through a No Exposure Certification (NEC) will maintain status under their existing NEC, which will remain valid until the expiration date identified on PADEP’s approval letter.  Facilities wishing to maintain their NEC status beyond the expiration date are required to apply to renew the NEC no later than 180 days prior to the expiration date of the NEC.

The renewed permit is substantially similar to the existing PAG-03, with a few notable changes.  The new PAG-03 now requires monitoring for Total Nitrogen and Total Phosphorus in all covered industrial sectors.  The new permit also specifies Target Quantitation Levels (TQLs) for many monitoring parameters that must be met or exceeded by the laboratory performing the analysis.  There is an additional, expanded Corrective Action Plan process that takes effect when a facility has four or more consecutive benchmark exceedances at a monitored outfall.  The new process requires a more systematic and thorough evaluation of stormwater BMP alternatives than the existing process, which begins after two or more benchmark exceedances.  There are also new requirements for managing certain authorized non-stormwater discharges as well as valve-controlled discharges from stormwater retention structures.

Covered facilities should review the new permit and discuss the new monitoring requirements and TQLs with their laboratory and/or consultant performing stormwater monitoring.  Prior to submitting the NOI for renewed PAG-03 coverage, facilities are also required to update their exiting PPCs Plans to conform with the new permit.