Massachusetts Municipal Separate Storm Sewer Systems Permit Finalized

With little fanfare and no significant changes from the draft published April 23, 2020, the U.S. Environmental Protection Agency (EPA) finalized modifications to the Clean Water Act (CWA) National Pollutant Discharge Elimination System (NPDES) general permit for stormwater discharges from small Municipal Separate Storm Sewer Systems (MS4s) to certain waters of the Commonwealth of Massachusetts (Massachusetts Small MS4 General Permit) on Dec. 7, 2020, which ended years of litigation. The permit becomes effective Jan. 6, 2021. A complete copy of the final permit with appendices can be found on EPA's website.

EPA issued its first small MS4 permit for Massachusetts in 2003, with its anticipated renewal scheduled for 2008. However, between 2008 and 2014, the EPA proposed a series of drafts before finally issuing the current permit on April 4, 2016, after receiving hundreds of comments. Thereafter, numerous stakeholders – including environmental organizations, municipalities and representatives from the construction industry – filed petitions for review in the U.S. Circuit Court of Appeals for the District of Columbia Circuit. After years of mediation, settlement agreements were reached in 2019, and public comment was solicited by notice published in the Federal Register on Dec. 27, 2019. Thereafter, the settlements were executed, and a notice of proposed permit modifications was published in the Federal Register on April 23. Given that the settlement agreements essentially precluded the petitioners from filing adverse comments, it is no surprise that the comments were largely supportive, as the EPA noted in its Response to Comments.

Many of the revisions were clarifying and consolidating, but several substantive changes were made, including specific requirements to address the Charles River Total Maximum Daily Load (TMDL) requirements and requirements for certain impaired waters. The following list briefly identifies notable changes:

• Section 2.1.1(d): Authorizes compliance schedules to comply with state water quality standards if compliance is infeasible within 60 days (including the new definition of "infeasible")
• Section 2.1.2(a): Clarifies that state conditions imposed on additional discharges are enforced through state law
• Section 2.3.3: Requires documents to be posted on websites to increase public availability
• Section 2.3.5: Confirms that compliance with the Construction General Permit (CGP) can be used to satisfy local ordinances
• Section 2.3.6: Clarifies and updates requirements for Low Impact Development (LID) unless infeasible
• Section 4.1: Addresses changes to Best Management Practices (BMPs) contained in Stormwater Management Plans and enforcement of requirements
• Section 5.1.5, 6.5 and Appendix F: New provisions to address the Charles River TMDL requirements
• Appendix H: New requirements for discharges to water bodies impaired for nitrogen, phosphorous, bacteria/pathogens, metals and oil/grease

Only time will tell if these changes will have the impact anticipated by the litigants.