COLUMBIA GAS TRANSMISSION, LLC — Warning Letter

120201013W_Warning Letter_04302020_text.pdf, page 1Official PDFWARNING LETTER OVERNIGHT EXPRESS DELIVERY April 30, 2020 Stanley G. Chapman, III Executive Vice-President and President, U.S. Natural Gas Pipelines TC Energy 700 Louisiana Street Houston, TX 77002 CPF 1-2020-1013W Dear Mr. Chapman: On April 4th and 6th, 2018, an inspector from the Public Utility Commission of Ohio (PUCO), acting as Agent for the Pipeline and Hazardous Materials Safety Administration (PHMSA), pursuant to Chapter 601 of 49 United States Code (U.S.C.), investigated Columbia Gas Transmission, LLC (Columbia)’s pipeline failure incident in Straitsville, Ohio. On April 3, 3018, a pipeline failure occurred on pipeline H109 as it crossed Monday Creek in Straitsville, Ohio. The 6-inch diameter pipeline on the west bank of the stream failed during heavy rainfall and flooding, resulting in an unintended gas release. As a result of the investigation, it is alleged that you have committed a probable violation of the Pipeline Safety Regulations, Title 49, Code of Federal Regulations (CFR). The item inspected and the probable violation is: 1. § 192.161 Supports and anchors. (a)… (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) … (2) Provision must be made for the service conditions involved. Columbia failed to install support on an exposed pipeline with provision made for the service conditions involved. Specifically, Columbia failed to install supports along its pipeline H109 as it crossed Monday Creek in Straitsville, Ohio. Provisions did not account for the creek crossing’s conditions.#

120201013W_Warning Letter_04302020_text.pdf, page 2CPF 1-2020-1013W On April 3, 3018, a pipeline failure occurred on pipeline H109 as it crossed Monday Creek in Straitsville, Ohio. The pipeline did not have any cables or other supports at the time of the rupture. However, the support columns, with no cables attached, were visible on each side of the creek crossing. During the investigation, the PUCO inspector reviewed a construction drawing from 1981 when this pipeline crossing was replaced. It showed that the pipeline was intended to be supported with cables. Columbia provided a few photos of the H109 creek crossing, from 2010 and the photos of the pipeline did not show cable supports connected to the pipe. Columbia did not have any timeframe for the installation or removal of the pipeline cable supports. Columbia also did not have documentation of any load support calculations or studies to validate removal of the pipeline cable supports at the H109 span crossing. Therefore, Columbia failed to install supports on the exposed portion of its H109 pipeline’s Monday Creek crossing with provisions made for the service conditions involved, by not using the cable supports that the construction drawing called for, or any other method of support. Under 49 U.S.C. § 60122 and 49 CFR § 190.223, you are subject to a civil penalty not to exceed $218,647 per violation per day the violation persists, up to a maximum of $2,186,465 for a related series of violations. For violation occurring on or after November 27, 2018 and before July 31, 2019, the maximum penalty may not exceed $213,268 per violation per day, with a maximum penalty not to exceed $2,132,679. For violation occurring on or after November 2, 2015 and before November 27, 2018, the maximum penalty may not exceed $209,002 per violation per day, with a maximum penalty not to exceed $2,090,022. For violations occurring prior to November 2, 2015, the maximum penalty may not exceed $200,000 per violation per day, with a maximum penalty not to exceed $2,000,000 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 item(s) identified in this letter. Failure to do so will result in Columbia Gas Transmission, LLC being subject to additional enforcement action. 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). No reply to this letter is required. If you choose to reply, please submit all correspondence in this matter to Robert Burrough, Director, PHMSA Eastern Region, 840 Bear Tavern Road, Suite 300, West Trenton, NJ 08628. Please refer to CPF 1-2020-1013W on each document you submit, and whenever possible provide a signed PDF copy in electronic format. Smaller files may be emailed to robert.burrough@dot.gov. Larger files should be sent on USB flash drive accompanied by the original paper copy to the Eastern Region Office. 120201013W_Warning Letter_04302020_text Page 2 of 3#

120201013W_Warning Letter_04302020_text.pdf, page 3CPF 1-2020-1013W Sincerely, Robert Burrough Director, Eastern Region Pipeline and Hazardous Materials Safety Administration CC: George Hamaty, US Regulatory Compliance Manager Eastern Region, TC Energy (via email) 120201013W_Warning Letter_04302020_text Page 3 of 3#