EAST TENNESSEE NATURAL GAS, LLC — Warning Letter

12026001WL_Warning Letter_04292026_(25-329586)_text.pdf, page 1Official PDFU.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 840 Bear Tavern Road, Suite 300 West Trenton, NJ 08628 609.771.7800 WARNING LETTER VIA EMAIL TO: matthew.akman@enbridge.com April 29, 2026 Matthew Akman EVP & President GTM East Tennessee Natural Gas LLC 915 North Eldridge Parkway Houston, TX 77079 CPF 1-2026-001-WL Dear Mr. Akman: From March 31 through December 11, 2025, a representative of the Pipeline and Hazardous Materials Safety Administration (PHMSA), Office of Pipeline Safety (OPS), Eastern Region, pursuant to Chapter 601 of Title 49 United States Code (U.S.C.), inspected East Tennessee Natural Gas LLC’s (ETNG) plans, procedures, records, and facilities in Georgia, North Carolina, Texas, Tennessee, and Virginia. As a result of the inspection, Eastern Region alleges that ETNG has committed probable violations of the Pipeline Safety Regulations, Title 49, Code of Federal Regulations (CFR) Part 192. The items inspected and the probable violations are: 1. § 192.161 Supports and anchors. (a) Each pipeline and its associated equipment must have enough anchors or supports to: (1) Prevent undue strain on connected equipment; (b) … (c) Each support or anchor on an exposed pipeline must be made of durable, noncombustible material and must be designed and installed as follows: (1) … (3) Movement of the pipeline may not cause disengagement of the support equipment.#

12026001WL_Warning Letter_04292026_(25-329586)_text.pdf, page 2CPF 1-2026-001-WL ETNG failed to have enough pipeline support to prevent undue strain on connected equipment and failed to ensure each support was designed and installed such that movement of the pipeline did not cause disengagement of the support equipment. Specifically, ETNG failed to ensure pipeline supports across the following 17 locations were in accordance with sections 192.161(a)(1) and 192.161(c)(3): 1. Boyds Creek Compressor Station: support not engaged with pipeline. 2. Dixon Springs Compressor Station: inadequate support due to movement of soil and/or pipeline. 3. Monterey Compressor Station: inadequate support due to movement of soil and/or pipeline. 4. Ridgetop Compressor Station: support not engaged with pipeline. 5. Tracy City Compressor Station: supports not engaged with pipeline. 6. Madisonville Compressor Station: supports not engaged with pipeline due to movement of soil and/or pipeline. 7. VS 3100-1 & M&R 59084: apparent missing support. 8. M&R 59313: support not engaged with pipeline. 9. MLV 3312 -1 & 2: apparent missing support. 10. M&R 59130: support corroded. 11. M&R 59102: apparent missing supports. 12. M&R 59099: apparent missing supports. 13. M&R 59040: apparent missing supports. 14. M&R 59134: apparent missing supports; supports not engaged with pipeline. 15. M&R 59177: apparent missing supports; supports not engaged with pipeline. 16. M&R 59026: supports not engaged with pipeline. Page 2 of 4#

12026001WL_Warning Letter_04292026_(25-329586)_text.pdf, page 3CPF 1-2026-001-WL 17. M&R 59054: apparent missing supports. Therefore, ETNG failed to have enough pipeline support to prevent undue strain on connected equipment and failed to ensure each support was designed and installed such that movement of the pipeline did not cause disengagement of the support equipment in accordance with sections 192.161(a)(1) and 192.161(c)(3). 2. § 192.706 Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line which transports gas in conformity with § 192.625 without an odor or odorant, leakage surveys using leak detector equipment must be conducted— (a) In Class 3 locations, at intervals not exceeding 7 ½ months, but at least twice each calendar year; [] ETNG failed to conduct leakage surveys of transmission lines which transport gas in conformity with § 192.625, without an odor or odorant, in Class 3 locations at intervals not exceeding 7 ½ months, but at least twice each calendar year. Specifically, ETNG failed to conduct surveys during calendar years 2022 through 2024 on its pipeline designated 3200-1, in accordance with section 192.706(a). During the inspection, the Eastern Region inspector requested leakage survey records of Class 3 areas for Line 3200-1 for calendar years 2022, 2023, and 2024. For calendar year 2023, ETNG only produced Work Order 14870861 (10/31/2023) for the Line 3200-1 Class 3 segment between mileposts 12.562 and 12.678. This record failed to demonstrate that ETNG conducted a leakage survey at least twice in 2023 for this transmission line. For calendar years 2022 and 2024, ETNG failed to produce any records. Therefore, ETNG failed to conduct leakage surveys of transmission lines which transport gas in conformity with § 192.625, without an odor or odorant, in Class 3 locations at intervals not exceeding 7 ½ months, but at least twice each calendar year in accordance with section 192.706(a). Under 49 U.S.C. § 60122 and 49 CFR § 190.223, you are subject to a civil penalty not to exceed $272,926 per violation per day the violation persists, up to a maximum of $2,729,245 for a related series of violations. For violations occurring on or after December 28, 2023 and before December 30, 2024 the maximum penalty may not exceed $266,015 per violation per day the violation persists, up to a maximum of $2,660,135 for a related series of violations. For violations occurring on or after January 6, 2023 and before December 28, 2023 the maximum penalty may not exceed $257,664 per violation per day the violation persists, up to a maximum of $2,576,627 for a related series of violations. For violations occurring on or after March 21, 2022 and before January 6, 2023 Page 3 of 4#

12026001WL_Warning Letter_04292026_(25-329586)_text.pdf, page 4CPF 1-2026-001-WL the maximum penalty may not exceed $239,142 per violation per day the violation persists, up to a maximum of $2,391,142 for a related series of violations. For violations occurring on or after May 3, 2021 and before March 21, 2022 the maximum penalty may not exceed $225,134 per violation per day the violation persists, up to a maximum of $2,251,334 for a related series of violations. For violations occurring on or after January 11, 2021 and before May 3, 2021 the maximum penalty may not exceed $222,504 per violation per day the violation persists, up to a maximum of $2,225,034 for a related series of violations. For violations occurring on or after July 31, 2019 and before January 11, 2021 the maximum penalty may not exceed $218,647 per violation per day the violation persists, up to a maximum of $2,186,465 for a related series of violations. We have reviewed the circumstances and supporting documents involved in this case and have decided not to conduct additional enforcement action or penalty assessment proceedings at this time. We advise you to correct the items identified in this letter. Failure to do so will result in ETNG being subject to additional enforcement action. No reply to this letter is required. If you choose to reply, in your correspondence please refer to 1- 2026-001-WL. Be advised that all material you submit in response to this enforcement action is subject to being made publicly available. If you believe that any portion of your responsive material qualifies for confidential treatment under 5 U.S.C. § 552(b), along with the complete original document you must provide a second copy of the document with the portions you believe qualify for confidential treatment redacted and an explanation of why you believe the redacted information qualifies for confidential treatment under 5 U.S.C. § 552(b). Sincerely, Robert Burrough Director, Eastern Region, Office of Pipeline Safety Pipeline and Hazardous Materials Safety Administration cc: Michael Koby, SVP & CEO, GTM, ETNG, michael.koby@enbridge.com Peter Seydewitz, Dir., Operational Excellence, ETNG, peter.seydewitz@enbridge.com Page 4 of 4#