Why Pennsylvania Facilities Follow DEP's PAG-03 Industrial Stormwater Permit Instead of the Federal MSGP
If you've managed industrial stormwater permits in other states, you probably know EPA's Multi-Sector General Permit, usually shortened to MSGP. It's the federal template for industrial stormwater, and plenty of states borrow from it, so it's natural to assume it governs your new Pennsylvania facility too. In most cases it doesn't. Pennsylvania runs its own Clean Water Act permitting program, and the Pennsylvania Department of Environmental Protection (DEP) issues its own general permit for industrial stormwater, called PAG-03. The two look alike at a glance, but a Pennsylvania facility follows PAG-03 and DEP's rules, not the MSGP.
This article walks through why that is, where the MSGP does apply, and how the two permits compare on structure, benchmark monitoring, written plans, reporting, and sector appendices. We also cover what carries over for managers who already know the MSGP and what to do first when a Pennsylvania site lands on your plate. If you'd like to talk through a specific facility, you can reach out to RMA at any point.
Table of Contents
TL;DR
EPA's Multi-Sector General Permit only covers industrial stormwater where EPA runs the permitting program, and that generally doesn't include Pennsylvania. EPA handed the program to the state, so DEP issues its own permit, PAG-03, which has a similar sector-based design and benchmark monitoring but adds its own requirements: a PPC Plan, sampling at least every six months, eDMR reporting, an annual report, and its own sector appendices. Experience with the MSGP helps, but a Pennsylvania facility needs to work from the current PAG-03 and its sector appendix, not the federal permit.
Does EPA's MSGP Apply to Pennsylvania Facilities?
For most Pennsylvania industrial facilities, no. The MSGP is a general permit that EPA writes and administers itself, and it only works where EPA is the NPDES permitting authority, meaning places where no state or tribe has taken over the program. NPDES stands for National Pollutant Discharge Elimination System, the Clean Water Act program that requires a permit to discharge pollutants, including stormwater from industrial sites, to waters of the United States. The usual list of EPA-run areas includes Massachusetts, New Hampshire, New Mexico, and the District of Columbia, along with certain territories and tribal lands. Pennsylvania isn't on it, and a facility here doesn't submit an MSGP Notice of Intent to EPA. If your site sits on tribal or federal land, or you aren't sure who the permitting authority is, confirm it with EPA and DEP before you assume either permit applies.
The MSGP is also in transition, which adds to the confusion when you read about it online. The 2021 version took effect on March 1, 2021 and expired on February 28, 2026. EPA published a proposed 2026 version in December 2024, and when we last checked, EPA was continuing the 2021 permit administratively for facilities that already had coverage while the replacement was pending. EPA's MSGP page has the current status. None of it changes anything for a Pennsylvania facility, but it explains why the federal permit can look like a moving target.
Names add to the confusion too. A few states call their own industrial stormwater permits a multi-sector general permit, and Florida is one example. Our article on Florida's MSGP shows how a state version can differ from EPA's. A permit with MSGP in its name isn't necessarily EPA's.
Why Does Pennsylvania Issue PAG-03 Instead of Using the MSGP?
The Clean Water Act lets EPA hand the NPDES program to states that build a qualifying program, and Pennsylvania did. Once that happens, the state agency issues and enforces the permits, and EPA doesn't issue its own stormwater general permit for sites inside that state. In Pennsylvania, the agency is the Department of Environmental Protection, or DEP, which works through its six regional offices and enforces under both the federal Clean Water Act and the state's Clean Streams Law. The state's NPDES rules are in 25 Pa. Code Chapter 92a.
A delegated state still has to meet federal minimums, but it's free to add to them, and DEP does. Its industrial stormwater general permit is PAG-03, formally the NPDES General Permit for Discharges of Stormwater Associated with Industrial Activity. DEP reissued it on December 24, 2022, and the current edition took effect on March 24, 2023 and runs through March 23, 2028. When DEP reissued the 2016 edition, it said it was trying to keep PAG-03 more consistent with EPA's MSGP, which is a big reason the two feel familiar. Familiar isn't the same as identical, though, and the differences are the part that trips up managers moving between states.
How Do the EPA MSGP and Pennsylvania's PAG-03 Compare Side by Side?
The table below puts the two permits next to each other at a high level. Both get reissued on a five-year cycle and details shift from edition to edition, so treat it as a map and confirm every number and deadline against the current permit document before you act on it.
| Feature |
EPA MSGP |
Pennsylvania PAG-03 |
| Who issues it |
EPA |
Pennsylvania DEP |
| Where it applies |
Areas where EPA is the permitting authority, such as Massachusetts, New Hampshire, New Mexico, DC, and certain territories and tribal lands |
Eligible industrial facilities in Pennsylvania |
| Current version |
2021 MSGP, expired February 28, 2026 and administratively continued for existing permittees; 2026 version proposed in December 2024 |
2023 PAG-03, effective March 24, 2023 through March 23, 2028 |
| Structure |
Core requirements plus requirements for 29 industrial sectors |
Parts A, B, and C for everyone, plus sector appendices A through U |
| Getting coverage |
Notice of Intent to EPA |
Notice of Intent to DEP, listing every outfall and including a site map |
| Written plan |
SWPPP |
PPC Plan |
| Benchmark monitoring |
Sector-based, on a schedule set in the permit (the 2021 version used a Year 1 and Year 4 pattern; the proposed 2026 version changes it) |
Sector-appendix parameters, at least one sampling event every six months |
| When results run high |
Additional Implementation Measures (AIM), triggered when results pass thresholds set in the permit |
Corrective Action Plan to DEP after two consecutive exceedances of the same pollutant at the same outfall |
| Reporting |
Monitoring results and annual reports to EPA |
eDMR for sampling results, plus an annual report on DEP's template due each March 23 |
| No exposure option |
Available under the federal stormwater rules |
No Exposure Certification approved by DEP, generally valid five years, not available for High Quality or Exceptional Value waters |
A few of those rows deserve a closer look, and the next sections take them one at a time.
What Do the MSGP and PAG-03 Have in Common?
If you've worked under the MSGP, a lot of PAG-03 will feel like home. Both are general permits, which means the agency writes one permit for a whole class of similar facilities and each facility signs up by filing a Notice of Intent instead of negotiating a custom permit. Both sort requirements by industrial sector, so a ready-mix plant and a scrap yard get different monitoring parameters. Both expect good housekeeping, spill prevention, inspections, employee training, and records. And both treat stormwater sample results as benchmarks, which are targets that signal whether your controls are working, not hard effluent limits. Our article on how benchmark values differ from effluent limits covers that distinction.
That shared DNA is why experience with the federal permit helps. You already understand outfalls, representative sampling, and the idea that a single high result is a warning rather than a violation. What changes is the paperwork wrapped around those ideas.
How Does a PPC Plan Differ From an MSGP SWPPP?
The biggest practical difference is the written plan. Under the MSGP, you develop a Stormwater Pollution Prevention Plan, or SWPPP. Under PAG-03, the equivalent document is the PPC Plan, short for Preparedness, Prevention and Contingency Plan. Both describe your site, map your drainage areas and outfalls, identify what could pollute runoff, and spell out the controls and procedures you use to prevent it. The PPC name reflects a Pennsylvania tradition of planning for spills and releases, and DEP builds its expectations around it.
A SWPPP written for another state's permit is a reasonable starting point, but it's organized around that permit's requirements, so it usually needs reworking to meet DEP's expectations and your sector appendix. Our comparison of SWPPPs and PPC Plans compared for PAG-03 goes through the differences in detail. DEP's review of the Notice of Intent also looks at the plan and the site map together, so a facility moving into Pennsylvania should expect to produce both rather than carry over a binder from elsewhere.
How Do PAG-03 Sampling and eDMR Reporting Differ From the MSGP?
Sampling is where managers feel the difference week to week. PAG-03 requires at least one sampling event every six months for each parameter, and permittees report the maximum daily concentration for each pollutant, not an average. DEP defines a qualifying storm event as one that produces more than 0.1 inch of precipitation, causes a discharge, and follows at least 72 hours after the previous storm. Grab samples are expected within the first 30 minutes of the discharge, and when that isn't possible you explain why in a comment on the report. The MSGP's benchmark schedule works differently, and the proposed 2026 version would change it again, so a monitoring calendar built for the federal permit won't carry over cleanly. Our guide to PAG-03 stormwater sampling covers the practical side of collecting samples that hold up.
Reporting goes through DEP's own systems. All industrial stormwater permittees in Pennsylvania use Pennsylvania's eDMR system for sampling results, and each year you also submit an annual report on DEP's template, due by March 23 for the prior calendar year. When the same pollutant exceeds its benchmark at the same outfall in two consecutive monitoring periods, you submit a Corrective Action Plan to DEP within 90 days of the end of the period that triggered it. After four consecutive exceedances, the plan has to consider the additional BMPs in DEP's checklist for your appendix. Consistent failure to get under the benchmarks can lead DEP to revoke general permit coverage and require an individual permit. If you're staring at a high result right now, see what to do when sampling results come back high. You can also read about what happens during a DEP stormwater inspection to see how these records get reviewed.
How Do PAG-03 Appendices Compare to MSGP Sectors?
The MSGP organizes its sector-specific requirements across 29 industrial sectors. PAG-03 uses appendices, lettered A through U, each tied to particular SIC codes and industrial activities. SIC stands for Standard Industrial Classification, and your primary SIC code, determined by which activity generates the most revenue at the site, usually decides whether you need permit coverage at all. If a facility has more than one covered activity, each corresponding appendix applies, and DEP applies them outfall by outfall.
The appendices carry the sector-specific benchmark parameters, best management practices, and, in some cases, special rules. Appendix K covers salt storage, Appendix G covers airports, and Appendix L covers hydrostatic test water for certain land transportation and petroleum bulk facilities, to give a few examples. Some facilities don't fit PAG-03 at all. Discharges to High Quality or Exceptional Value waters aren't eligible, and neither are facilities subject to certain federal effluent limit guidelines, such as asphalt emulsion plants, which need an individual permit. Those routes are laid out in our article on general, individual, and No Exposure permits, and what No Exposure means explains the option for sites with nothing exposed. For the basics of coverage, see who needs a stormwater permit.
What Happens When the MSGP or PAG-03 Gets Reissued?
Both permits run on five-year cycles, and both change when they're reissued. The federal side is unsettled right now, as covered above, and the proposed 2026 MSGP includes changes such as a different benchmark schedule and report-only PFAS monitoring for many sectors. Those are proposals, not requirements, and nothing in the MSGP binds a Pennsylvania facility. They're still worth a glance, because EPA's changes tend to influence state permits at later reissuance cycles.
For PAG-03, the current edition expires on March 23, 2028. The last time around, DEP published a draft for public comment in August 2022, published the final permit in December 2022, and required existing permittees to file a new Notice of Intent by March 23, 2023 to stay covered. Expect a similar pattern ahead of 2028, and plan for your PPC Plan, sampling parameters, and paperwork to need updates. The safest habit is to work from the permit text and your appendix on DEP's site and never from a copy of an old permit or from another state's version. Our article on how long PAG-03 coverage takes walks through the coverage timeline.
What Should You Do First With a Pennsylvania Industrial Stormwater Permit?
Start with the facts of the site. Pin down your primary SIC code, which industrial activities and materials are exposed to rain and snow, and where your stormwater goes. A facility that discharges to a municipal storm sewer or a stream usually needs coverage or a No Exposure Certification if its category is covered. Some older cities have combined sewers, and where runoff goes to a treatment plant, the sewer authority's rules may apply instead, so local rules are worth confirming. Plenty of businesses, such as warehouses, body shops, and dealerships, probably don't need PAG-03 at all, though that depends on your SIC code and what's exposed.
Next, find out whether anyone already holds coverage at the site. If you're buying or taking over a facility, DEP has a transfer process for permit coverage, and an existing PPC Plan and sampling history will save you real time. If nobody does, you'll need to work through the Notice of Intent, the plan, and the sampling information DEP asks for, and getting PAG-03 coverage yourself lays out what that looks like if you'd rather handle parts of it in-house. Once you're covered, your team needs to know what the plan requires, and our online training library is a practical place to start. For the national background, see everything you need to know about NPDES stormwater permits.
How Does RMA Help With PAG-03 and Pennsylvania Stormwater Permits?
RMA is a family-run environmental consulting firm based in New Jersey, and we work with facilities across Pennsylvania on industrial stormwater. If you're coming from an MSGP state, we can help you figure out whether PAG-03, a No Exposure Certification, or an individual permit fits your site, then prepare the PPC Plan and Notice of Intent, work through DEP's review with you, and help with the sampling, eDMR reporting, annual reports, and corrective action that follow. Senior staff do the work, and we'll tell you plainly if a simpler route makes sense or if you don't need us.
There's no pressure and no obligation. You can call us, send an email, or fill out the form on our website. Whenever you're ready, reach out to RMA and we'll help you work out what your Pennsylvania facility needs.
