(a) The operator of any regulated small MS4 under §122.32 must seek coverage under an NPDES permit issued by the applicable NPDES permitting authority. If the small MS4 is located in an NPDES authorized State, Tribe, or Territory, then that State, Tribe, or Territory is the NPDES permitting authority. Otherwise, the NPDES permitting authority is the EPA Regional Office for the Region where the small MS4 is located.

(b) The operator of any regulated small MS4 must seek authorization to discharge under a general or individual NPDES permit, as follows:

(1) General permit.

(i) If seeking coverage under a general permit issued by the NPDES permitting authority in accordance with §122.28(d)(1), the small MS4 operator must submit a Notice of Intent (NOI) to the NPDES permitting authority consistent with §122.28(b)(2). The small MS4 operator may file its own NOI, or the small MS4 operator and other municipalities or governmental entities may jointly submit an NOI. If the small MS4 operator wants to share responsibilities for meeting the minimum measures with other municipalities or governmental entities, the small MS4 operator must submit an NOI that describes which minimum measures it will implement and identify the entities that will implement the other minimum measures within the area served by the MS4. The general permit will explain any other steps necessary to obtain permit authorization.

(ii) If seeking coverage under a general permit issued by the NPDES permitting authority in accordance with §122.28(d)(2), the small MS4 operator must submit an NOI to the Director consisting of the minimum required information in §122.28(b)(2)(ii), and any other information the Director identifies as necessary to establish additional terms and conditions that satisfy the permit requirements of §122.34, such as the information required under §122.33(b)(2)(i). The general permit will explain any other steps necessary to obtain permit authorization.

(2) Individual permit.

(i) If seeking authorization to discharge under an individual permit to implement a program under §122.34, the small MS4 operator must submit an application to the appropriate NPDES permitting authority that includes the information required under §122.21(f) and the following:

(A) The best management practices (BMPs) that the small MS4 operator or another entity proposes to implement for each of the storm water minimum control measures described in §122.34(b)(1) through (6);

(B) The proposed measurable goals for each of the BMPs including, as appropriate, the months and years in which the small MS4 operator proposes to undertake required actions, including interim milestones and the frequency of the action;

(C) The person or persons responsible for implementing or coordinating the storm water management program;

(D) An estimate of square mileage served by the small MS4;

(E) Any additional information that the NPDES permitting authority requests; and

(F) A storm sewer map that satisfies the requirement of §122.34(b)(3)(i) satisfies the map requirement in §122.21(f)(7).

(ii) If seeking authorization to discharge under an individual permit to implement a program that is different from the program under §122.34, the small MS4 operator must comply with the permit application requirements in §122.26(d). The small MS4 operator must submit both parts of the application requirements in §122.26(d)(1) and (2). The small MS4 operator must submit the application at least 180 days before the expiration of the small MS4 operator's existing permit. Information required by §122.26(d)(1)(ii) and (d)(2) regarding its legal authority is not required, unless the small MS4 operator intends for the permit writer to take such information into account when developing other permit conditions.

(iii) If allowed by your NPDES permitting authority, the small MS4 operator and another regulated entity may jointly apply under either paragraph (b)(2)(i) or (ii) of this section to be co-permittees under an individual permit.

(3) Co-permittee alternative. If the regulated small MS4 is in the same urbanized area as a medium or large MS4 with an NPDES storm water permit and that other MS4 is willing to have the small MS4 operator participate in its storm water program, the parties may jointly seek a modification of the other MS4 permit to include the small MS4 operator as a limited co-permittee. As a limited co-permittee, the small MS4 operator will be responsible for compliance with the permit's conditions applicable to its jurisdiction. If the small MS4 operator chooses this option it must comply with the permit application requirements of §122.26, rather than the requirements of §122.33(b)(2)(i). The small MS4 operator does not need to comply with the specific application requirements of §122.26(d)(1)(iii) and (iv) and (d)(2)(iii) (discharge characterization). The small MS4 operator may satisfy the requirements in §122.26 (d)(1)(v) and (d)(2)(iv) (identification of a management program) by referring to the other MS4's storm water management program.

(4) Guidance for paragraph (b)(3) of this section. In referencing the other MS4 operator's storm water management program, the small MS4 operator should briefly describe how the existing program will address discharges from the small MS4 or would need to be supplemented in order to adequately address the discharges. The small MS4 operator should also explain its role in coordinating storm water pollutant control activities in the MS4, and detail the resources available to the small MS4 operator to accomplish the program.

(c) If the regulated small MS4 is designated under §122.32(a)(2), the small MS4 operator must apply for coverage under an NPDES permit, or apply for a modification of an existing NPDES permit under paragraph (b)(3) of this section, within 180 days of notice of such designation, unless the NPDES permitting authority grants a later date.

[81 FR 89348, Dec. 9, 2016]