Permits; Applications, Issuances, etc.: New Mexico and Oklahoma Statewide Tribal Municipal Separate Storm Sewer System

New Mexico and Oklahoma Statewide Tribal Municipal Separate Storm Sewer System (MS4) General Permit Proposal

DATES:

Comments must be submitted in writing to EPA on or before May 4, 2026. A virtual public hearing will be held. More information on the date and how to participate will be posted on the EPA public notices web page at https://www.epa.gov/publicnotices at least 30 days prior to the virtual public hearing.

Proposed Documents: A draft permit, fact sheet, and other supporting documents are available online via the docket for this action at: https://www.regulations.gov or on EPA public notices web pages at: https://www.epa.gov/publicnotices/notices-search .

To obtain hard copies of these documents or any other information in the administrative record, please email [email protected].

SUPPLEMENTARY INFORMATION:

How do I comment on this proposal?

Comment Submittals: You may send comments, identified by Docket ID. No. EPA-R06-OW-2026-1288; by any of the following methods:

• Federal eRulemaking Portal: https://www.regulations.gov/ (our preferred method).

• By Email: Send comments by email to [email protected]. Include Docket ID. No. EPA-R06-OW-2026-1288, in the subject line of the email.

• By Mail/Hand Delivery/Courier: Deliver comments to U.S. EPA, Attn: 6WDPE, 1201 Elm Street, Dallas, Texas 75270.

• We encourage the public to submit comments via www.Regulations.gov or via email.

• Please submit your comments within the specified time period cited in the DATES section of this document. Comments received after the close of the comment period will be marked "late". The EPA is not required to consider these late comments. All comments received by the EPA in accordance with this section by the ending date of the comment period will be considered by the EPA before a final decision is made regarding permit issuance.

• Once submitted, comments cannot be edited or removed from the docket. The EPA may publish any comment received to its public docket.

Do not submit to EPA's docket or email any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission ( i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.

Administrative record: All documents and references used in the development of this permit are part of the Administrative Record for this permit. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, will be publicly available only in hard copy. Publicly available materials are available either electronically or in hard copy from [email protected]. The Administrative Record may also be viewed at the EPA Region 6 Offices from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. For more information on scheduling a time to view the Record or to obtain copies of available documents, please email [email protected].

Purpose of This Proposal: This permit NPDES Permit NMR04I000/OKR04I000 is intended to replace both expired general permits NPDES Permit NMR04000I/OKR040001 for discharges in the state of New Mexico and Oklahoma. The discharge control conditions established by this permit are based on the Clean Water Act (CWA) section 402(p)(3)(B), which mandates that a permit for discharges from MS4s must effectively prohibit the discharge of non-stormwater to the MS4; and require controls to reduce pollutants in discharges from the MS4 to the maximum extent practicable (MEP) including best management practices (BMPs), control techniques, and system, design and engineering methods, and such other provisions as the Administrator deems appropriate for the control of pollutants. The MEP is the statutory standard that established the level of pollutant reductions that MS4 operators must achieve. The MEP is the statutory standard that established the level of pollutant reductions that both Phase I and Phase II MS4 operators must achieve. This MS4 permit requires implementation of BMPs addressing the six minimum control measures in 40 CFR 122.34(b), that are generally deemed to be an appropriate means of meeting the MEP standard. The overall intent of the permit conditions is to support the statutory goals of section 101 of the CWA to restore and maintain the chemical, physical and biological integrity for the Nations waters. The 1987 Water Quality Act (WQA) amended the Clean Water Act by adding section 402(p) which requires that NPDES permits be issued for various categories of storm water discharges. Section 402(p)(2) of the CWA requires permits for five categories of storm water discharges, commonly referred to as Phase I of the NPDES Storm Water Program. Included in Phase I are discharges from large MS4s (systems serving a population of 250,000 or more and medium MS4s (systems serving a population of 100,000 to 250,000). Phase I regulations (40 CFR 122.26) published November 16, 1990 (55 FR 47990) addressed discharges from large and medium MS4s. Section 402(p)(6) of the CWA requires permitting for certain additional storm water discharges (Phase II of the storm water program) to protect water quality. EPA promulgated final Phase II storm water regulations on December 8, 1999 (64 FR 68722). These regulations set forth the additional categories of discharges to be permitted and the requirements of the program. The additional discharges to be permitted included small MS4s located in Urbanized Areas designated by the Bureau of the Census and those designated by the Director on a case-by-case basis to protect water quality. This permit combines coverage for both Phase I and Phase II regulated MS4s in a single general permit. As authorized by 40 CFR 122.44(k), the permit utilizes controls in the form of a comprehensive Stormwater Management Program (SWMP), as the mechanism to implement the statutory requirements.

Authority: Clean Water Act, 33 U.S.C. 1251 et seq.