On March 2, 2020, the U.S. Environmental Protection Agency (EPA) published a notice¹ and request for comment for its National Pollutant Discharge Elimination System (NPDES) 2020 Issuance of the Multi-Sector General Permit (MSGP) for Stormwater Discharges Associated with Industrial Activity. Comments are due by May 1, 2020. Substantial changes are proposed as a result of litigation over the 2015 permit. Settlement² of that litigation required a study³ to evaluate several issues falling broadly into three categories: 1) the scope of benchmark monitoring, including whether polycyclic aromatic hydrocarbons (PAHs) should be included for industries where petroleum hydrocarbons are a risk; 2) the feasibility of imposing "numeric retention standards (e.g. volumetric control standards for a percent storm size or based on percentage of imperviousness);" and 3) whether highest-priority industrial facilities or subsectors should have additional requirements.

Key proposed changes in the permit include:

1. streamlining and reorganizing the permit sections and other administrative changes
2. special provisions for stormwater discharges to a federal Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) site
3. prohibiting discharges where coal-tar sealcoat is used due to concerns about polycyclic aromatic hydrocarbons (PAHs)
4. delaying authorization where an enforcement action is pending or proposed
5. requiring public signage of permit coverage, including how to report a problem
6. consideration of major storm control measure enhancements under certain circumstances
7. adding universal benchmark monitoring for all sectors to include pH, Total Suspended Solids (TSS) and Chemical Oxygen Demand (COD)
8. revision to impaired waters monitoring requirements and the method for determining natural background
9. updating benchmark values based on the latest toxicity information for certain metals
10. adding benchmark monitoring for Sector I (oil and gas extraction), Sector P (land transportation and warehousing) and Sector R (ship and boat building and repair yards)
11. requiring additional implementation measures based on a tiered approach, depending on the nature and magnitude of the benchmark threshold exceedance
12. revising sector-specific fact sheets to include information about control measures and stormwater pollution prevention for each sector to incorporate emerging stormwater control measures

The EPA also requests comment on a number of subjects ranging from administrative changes to collection of additional data, which the EPA determined it was lacking to fully evaluate the study's recommendations. The docket⁴ includes 70 supporting documents. The EPA hosted an informational webinar on March 10, 2020, which can be viewed by registering here.⁵ Comments can be submitted electronically at regulations.gov for Docket ID: EPA-HQ-OW-2019-0372.

Notes

¹ National Pollutant Discharge Elimination System (NPDES) 2020 Issuance of the Multi-Sector General Permit for Stormwater Discharges Associated with Industrial Activity

² 2015 MSGP Settlement Agreement

³ Improving the EPA Multi-Sector General Permit for Industrial Stormwater Discharges

⁴ National Pollutant Discharge Elimination System (NPDES) Multi-Sector General Permit (MSGP) for Stormwater from Industrial Activities

⁵ Proposed 2020 Multi-Sector General Permit (MSGP) Informational Webcast