New U.S. EPA Multi-Sector General Permit: PFAS Monitoring Now Required
Posted: January 2nd, 2025
Authors: Evan M.
What is the MSGP?
The Multisector General Permit (MSGP) is a permit issued by the United States Environmental Protection Agency’s (U.S. EPA) National Pollutant Discharge Elimination System (NPDES) program which regulates stormwater discharges from industrial activities, as defined in 40 CFR 122.26(b)(14). The purpose of the NPDES program is to protect the quality of waters of the United States. This MSGP would only apply to Massachusetts, New Hampshire, and New Mexico as they are not given delegated authority by U.S. EPA. While the new MSGP only impacts three states, many states use the MSGP as a model for their own state-issued permit.
2026 Proposed MSGP
On December 13, 2024 U.S. EPA published the proposed 2026 MSGP in the Federal Register for comment. The most significant change can be seen in Part 4.2.1.1.c of the Proposed 2026 MSGP. This part requires sectors A, B, C, D, F, I, K, L, M, N, P, R, S, T, U, V, W, X, Y, Z, AA, AB, and AC to conduct quarterly “report-only” indicator analytical monitoring for per- and polyfluoroalkyl substances (PFAS). Once finalized this MSGP will replace U.S. EPA’s existing MSGP which expires on February 28, 2026, and will last a term of five years. U.S. EPA is taking public comments on the new MSGP until February 11, 2025.
The inclusion of PFAS in monitoring requirements is a new focus in the regulatory world but is not unheard of. Last year, the Pennsylvania Department of Environmental Protection (PADEP) added PFAS to its NPDES Individual Industrial Wastewater permit application process; see the ALL4 blog here. This step by U.S. EPA displays its increased focus on the PFAS regulatory framework.
Other notable changes proposed for the 2026 MSGP include additional requirements for stormwater control measure designs, revisions to water quality-based effluent limitations, and the change in status from indicator to benchmark for certain parameters and sectors, impaired waters monitoring, and additional implementation measures for certain corrective actions.
Preparing for the new MSGP
Industries affected by the new rule should review the MSGP PFAS monitoring and reporting requirements and assess their potential PFAS sources. Other considerations include updating stormwater pollution prevention plans (SWPPPs), researching accredited labs for PFAS testing, and staying up to date on PFAS treatment technologies, which are essential steps to ensure compliance.
ALL4 has extensive experience in both NPDES and PFAS and is ready to assist with any need, from permitting to compliance strategies and sampling. For more information, please contact Evan Mia at emia@all4inc.com.