Regulatory Alert: EPA Releases Final 2021 Multi-Sector General Permit for Stormwater Discharges
January 19, 2021
Yesterday the U.S. Environmental Protection Agency (EPA) released the final multi-sector general permit (MSGP), which outlines the terms and conditions for authorizing certain airports to discharge industrial stormwater. The final 2021 MSGP will replace the existing 2015 MSGP and go into effect on March 1 for a period of five years. 
AAAE is pleased that EPA's final 2021 MSGP removed two controversial and costly mandates that the agency proposed in a draft MSGP last spring. In the proposed MSGP, EPA would have significantly expanded the number of airports that must conduct benchmark monitoring and required the implementation of costly stormwater control measures under certain conditions. AAAE, working with members and our industry partners, strongly pushed back on both provisions in comments to the agency last June. AAAE is also pleased that there are no requirements for permit holders regarding per- and polyfluoroalkyl substances (PFAS), despite requests to EPA from members of the public and some state environmental agencies.
Background. In accordance with the Clean Water Act, EPA implements the National Pollutant Discharge Elimination System (NPDES) program, which requires permits for any person or organization, including airports, to discharge industrial stormwater into waters of the United States. EPA's first MSGP was issued in 1995 and revised in 2000, 2008, and 2015, to provide operators with coverage for such stormwater discharge. The MSGP only provides coverage for four states, Washington, D.C., many Tribal areas, and U.S. territories, where EPA is the NPDES permitting authority. However, many states use the MSGP as a model for developing their own industrial stormwater discharge permits, reflecting its importance for the industry and airports. 
In June, AAAE submitted comments in response to EPA's proposed 2020 MSGP which the agency circulated as a proposed replacement for the existing 2015 MSGP. Based on key feedback from members and working with our industry partners, AAAE provided EPA with a series of recommended changes to the proposed 2020 MSGP that focused on ensuring EPA-permitted airports have the flexibility to implement their stormwater management program and manage benchmark exceedances, if any, in a manner that is best suited for their particular circumstances. You can read AAAE's comments here. 
Final 2021 Permit Highlights. Upon going into effect, the final 2021 MSGP will make a number of changes to the current 2015 MSGP and the proposed 2020 MSGP that was made available for comment last spring. The following is a brief summary of highlights from the final 2021 MSGP. 
What's Next? The final 2021 MSGP, which was signed on January 15, will go into effect on March 1, 2021 and expire on February 28, 2026. The permit will replace the existing 2015 MSGP, which had been administratively continued after it expired in June 2020. AAAE will be working with airport members and the Environmental Services Committee to facilitate discussion and education on implications of the new permit. 
If you have any questions, comments, or other feedback regarding the final 2021 MSGP, please contact Justin Barkowski at justin.barkowski@aaae.org. 
 
Yesterday the U.S. Environmental Protection Agency (EPA) released the final multi-sector general permit (MSGP), which outlines the terms and conditions for authorizing certain airports to discharge industrial stormwater. The final 2021 MSGP will replace the existing 2015 MSGP and go into effect on March 1 for a period of five years. 
AAAE is pleased that EPA's final 2021 MSGP removed two controversial and costly mandates that the agency proposed in a draft MSGP last spring. In the proposed MSGP, EPA would have significantly expanded the number of airports that must conduct benchmark monitoring and required the implementation of costly stormwater control measures under certain conditions. AAAE, working with members and our industry partners, strongly pushed back on both provisions in comments to the agency last June. AAAE is also pleased that there are no requirements for permit holders regarding per- and polyfluoroalkyl substances (PFAS), despite requests to EPA from members of the public and some state environmental agencies.
Background. In accordance with the Clean Water Act, EPA implements the National Pollutant Discharge Elimination System (NPDES) program, which requires permits for any person or organization, including airports, to discharge industrial stormwater into waters of the United States. EPA's first MSGP was issued in 1995 and revised in 2000, 2008, and 2015, to provide operators with coverage for such stormwater discharge. The MSGP only provides coverage for four states, Washington, D.C., many Tribal areas, and U.S. territories, where EPA is the NPDES permitting authority. However, many states use the MSGP as a model for developing their own industrial stormwater discharge permits, reflecting its importance for the industry and airports. 
In June, AAAE submitted comments in response to EPA's proposed 2020 MSGP which the agency circulated as a proposed replacement for the existing 2015 MSGP. Based on key feedback from members and working with our industry partners, AAAE provided EPA with a series of recommended changes to the proposed 2020 MSGP that focused on ensuring EPA-permitted airports have the flexibility to implement their stormwater management program and manage benchmark exceedances, if any, in a manner that is best suited for their particular circumstances. You can read AAAE's comments here. 
Final 2021 Permit Highlights. Upon going into effect, the final 2021 MSGP will make a number of changes to the current 2015 MSGP and the proposed 2020 MSGP that was made available for comment last spring. The following is a brief summary of highlights from the final 2021 MSGP. 
- No Universal Benchmark Monitoring. The biggest and most positive development is EPA's removal of the proposed universal benchmark monitoring requirement. Under the proposed 2020 MSGP, EPA would have required all permit holders to conduct universal benchmark monitoring in all sectors, including air transportation facilities, regardless of facility risk or prior history. AAAE significantly pushed back on this provision, arguing it would be too costly for airports and EPA has not provided any basis for expanding the scope of airports subject to this type of monitoring. EPA did not include this requirement in the final 2021 MSGP, an important win for those airports that have not previously been subject to benchmark monitoring requirements. 
- New 'Indicator Monitoring' Requirement. The 2021 MSGP includes an additional indicator monitoring requirement for airports that have stormwater discharges from paved surfaces that will be initially sealed or re-sealed with coal-tar sealcoat. Any EPA-permitted airport with such discharge will have to monitor for polycyclic aromatic hydrocarbons (PAHs) twice per year during their first and fourth years of coverage under the permit. However, this is a report-only requirement and there is no threshold or baseline value; this means there is no follow-up action triggered or required based on the sample results. 
- No Requirement to Implement Prescriptive Control Measures. Under the proposed 2020 MSGP, EPA would have required permitted airports to implement a laundry list of stormwater control measures when benchmark monitoring results exceed or repeatedly exceed benchmark values. AAAE strongly pushed back on this proposal, arguing that requiring the consideration and/or implementation of prescriptive control measures is contrary to a proper engineering analysis. In addition, some of the proposed control measures were outdated and no longer viable. EPA ultimately did not include this requirement in the final MSGP. 
- No Requirements on PFAS. The 2021 MSGP does not include any requirements for permit holders regarding PFAS, despite requests to EPA from members of the public and some state environmental agencies. In the pre-publication Federal Register notice, EPA indicated that the agency revised each of the sector-specific fact sheet guidance documents to include practices that could be used by operators to minimize PFAS in stormwater discharges. However, those guidance documents do not appear to have been released yet. 
- Composite Sampling Permitted. The final MSGP allows airports to use the composite sampling method instead of taking grab samples to comply with monitoring requirements. AAAE supported this change because most airports believe that utilizing composite sampling techniques would be more economical and provide more reliable and consistent data on pollutant concentration compared to grab samples. 
What's Next? The final 2021 MSGP, which was signed on January 15, will go into effect on March 1, 2021 and expire on February 28, 2026. The permit will replace the existing 2015 MSGP, which had been administratively continued after it expired in June 2020. AAAE will be working with airport members and the Environmental Services Committee to facilitate discussion and education on implications of the new permit. 
If you have any questions, comments, or other feedback regarding the final 2021 MSGP, please contact Justin Barkowski at justin.barkowski@aaae.org. 
 
