Att11B_NationwidePermitVerification_0005.pdf

DEPARTMENT OF THE ARMY

U.S. ARMY CORPS OF ENGINEERS, OMAHA DISTRICT

MONTANA REGULATORY OFFICE

100 NEILL AVENUE

HELENA, MT 59601-3329

November 20, 2025

SUBJECT: Nationwide Permit Verification, NWO-2025-01382-MT, BLM - Melstone Dam Maintenance/Rehabilitation - Musselshell County

Bureau of Land Management Attn: Josh Helm 111 Garryowen Rd Miles City MT, 59301 jhelm@blm.gov

Dear Mr. Helm:

This letter is in response to your September 16, 2025 Pre-construction Notification (PCN), requesting Department of the Army (DA) Nationwide Permit (NWP) verification for the above-referenced project. The project site is located on Melstone Reservoir at Latitude 46.603897°, Longitude -107.901337°; Section 26, Township 10 N, Range 30 E; near Melstone, Musselshell County, Montana.

Project-specific components:

1. Outlet Demolition: Removal of the existing 76-foot of 24-inch reinforced concrete pipe (RCP). The demolition and associated excavated material will be removed from the area and placed into uplands resulting in 0.03 acre of temporary impact.

This temporary impact will not occur below the ordinary high-water mark

(OHWM).

2. Outlet Construction: Placement of 120-foot, of 30-inch RCP, construct a 58-foot by 53-foot stilling basin,11-foot inlet tower with a precast manhole. Furthermore a 475-foot toe drain will be installed. The Outlet construction would impact approximately 0.05 acre below OHWM.

3. Slope Stabilization: Approximately 5,380 cubic yards of riprap material will be used to provide upstream slope protection and bedding. The discharge will result in an impact of approximately 0.6 acre below OHWM.

4. Project will be completed as detailed to the plans titled, “Melstone Dam

Reconstruction”, dated, November 22, 2024.

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The Omaha District, Regulatory Branch is committed to providing quality and timely service to our customers. In an effort to improve customer service, please take a moment to complete our Customer

Service Survey found on our website at: https://regulatory.ops.usace.army.mil/customer-service-survey/.

The U.S. Army Corps of Engineers (Corps) regulates the discharge of dredged and fill material into waters of the United States under Section 404 of the Clean Water Act (CWA) (33 U.S.C. 1344) and structures or work in, over, and under navigable waters of the United States under Section 10 of the Rivers and Harbors Act (RHA) (33 U.S.C.

403). The Corps’ regulations are published in the Code of Federal Regulations at 33 CFR parts 320 through 332. NWPs are defined in the Federal Register published on December 27, 2021 (86 FR 73522 and January 13, 2021 (86 FR 2744)). Based on a review of the information you furnished and available to us, we have determined the above referenced work requires DA authorization under Section 404 of the CWA.

Based upon the information you provided, we hereby verify that the work described above, which would be performed in accordance with the plans you provided (sheets 1-27), dated November 22, 2024, is authorized by NWP 3, Maintenance.

Please note that deviations from the original plans and specifications of your project could require additional authorization from this office. This NWP and associated Regional and General Conditions are enclosed and can be accessed on our website at:

https://www.nwo.usace.army.mil/Missions/Regulatory-Program/Montana/. Failure to comply with the General and Regional Conditions of this NWP, may result in the suspension or revocation of your authorization, and you may be subject to appropriate enforcement action. You shall comply with all terms and conditions associated with this

NWP.

Unless this NWP is suspended, modified, or revoked, it is valid until March 14, 2026. It is incumbent upon you to remain informed of changes to this NWP. We will issue a public notice when the NWPs are reissued. Furthermore, if you commence or are under contract to commence this activity before the date that the relevant NWP is modified or revoked, you will have twelve (12) months from the date of the modification or revocation of the NWP to complete the activity under the present terms and conditions of this NWP unless discretionary authority has been exercised on a case-by-case basis to modify, suspend, or revoke the authorization as per 33 CFR 330.6(b).

Any project specific conditions listed in this letter continue to remain in effect after the NWP verification expires unless the district engineer removes those conditions.

To assist in your compliance with NWP General Condition 30, enclosed is a "Compliance Certification" form, which shall be signed and returned within 30 days of completion of the project, including any required mitigation. Your signature on this form certifies that you have completed the work in accordance with the terms and conditions of the NWP. Activities completed under the authorization of an NWP which was in effect at the time the activity was completed continue to be authorized by that NWP.

Authorizations under this NWP does not relieve permittees from obtaining permits or other authorizations from any required federal, state, or local agency.

https://regulatory.ops.usace.army.mil/customer-service-survey/

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The Omaha District, Regulatory Branch is committed to providing quality and timely service to our customers. In an effort to improve customer service, please take a moment to complete our Customer

Service Survey found on our website at: https://regulatory.ops.usace.army.mil/customer-service-survey/.

If you have any questions, please contact Colten Shimer via email at Colten.D.Shimer@usace.army.mil, by mail at the address above, or by phone at (406) 200-2689.

Sincerely, Colten Shimer Project Manager

3 Enclosures

1. NWP 3 Fact Sheet with Regional and General Conditions

2. Compliance Certification

3. CWA Section 401 Water Quality Certification https://regulatory.ops.usace.army.mil/customer-service-survey/