Notice of Preliminary Designation of Certain Stormwater Discharges in the Commonwealth of Massachusetts and Notice of Availability of Draft Permit Under the National Pollutant Discharge Elimination System of the Clean Water Act

The Environmental Protection Agency ("EPA") is providing notice of two proposed actions.

Federal Register Link: https://www.federalregister.gov/documents/2024/10/31/2024-25219/notice-of-preliminary-designation-of-certain-stormwater-discharges-in-the-commonwealth-of

The first action is the Preliminary Designation of certain stormwater discharges from commercial, industrial, and institutional properties with one acre or more of impervious surface in the Charles, Neponset, and Mystic River watersheds in Massachusetts for regulation under the Clean Water Act's ("CWA") National Pollutant Discharge Elimination System ("NPDES") permitting program.

EPA Region 1 is concurrently providing notice of availability of a draft NPDES General Permit for Private Commercial Industrial, and Institutional Stormwater Discharges in the Charles, Mystic, and Neponset River Watersheds in Massachusetts ("Draft CII GP"). Entities included in the Preliminary Designation and eligible for coverage under the Draft CII GP Permit are: commercial, industrial, and institutional properties with one acre or more of impervious surface in the Charles, Neponset, and Mystic River watersheds in Massachusetts.

For more information on this matter please refer to this website.

The public comment period for both of these proposed actions will remain open from October 31, 2024 to January 29, 2025. Interested parties can submit comments on the Preliminary Designation and the Draft Permit at www.regulations.gov/docket/EPA-R01-OW-2024-0492. All comments must be received by January 29, 2025. 

Relevant documents include:

• Preliminary Determination (pdf) (7.03 MB)
• Draft Permit (pdf) (577.34 KB)
• Appendix A - Definitions, Abbreviations, and Acronyms (pdf) (146 KB)
• Appendix B - Standard Permit Conditions Applicable to All Authorized Discharges (pdf) (172.62 KB)
• Appendix C - Endangered Species Act (pdf) (555.68 KB)
• Appendix D - National Historic Preservation Act Eligibility Guidance (pdf) (209.38 KB)
• Appendix E - Determining Impervious Cover Acreage (pdf) (205.35 KB)
• Appendix F - Phosphorus Reduction Credits for Selected Non-Structural and Structural Stormwater Control Measures ("SCMs") (pdf) (1.84 MB)
• Appendix G - Notices of Intent ("NOI"), Change ("CNOI"), and Termination ("NOT") (pdf) (214.21 KB)
• Appendix H - Massachusetts Tax Assessor’s Use Code for CII Land Uses (pdf) (232.44 KB)
• Appendix I - Operations and Maintenance Requirements (pdf) (175.86 KB)
• Appendix J - Methodology for Determining Site-Specific Pollutant Calculation (pdf) (303.23 KB)
• Appendix K - Reporting Requirements for Annual Reports (pdf) (99.67 KB)
• Fact Sheet (pdf) (828.22 KB)
• Administrative Record Preliminary Designation
• Administrative Record Draft Permit

For questions contact:
Laura Schifman
US Environmental Protection Agency – Region 1
5 Post Office Square, Suite 100 (WIP06-1)
Boston, MA 02109
Telephone: (617) 918-1015
Email: R1.RDA@epa.gov