GREAT LAKES GAS TRANSMISSION CO — Warning Letter

12021042WL_Warning Letter_05062021_(20-174444)_text.pdf, page 1Official PDFWARNING LETTER OVERNIGHT EXPRESS DELIVERY May 6, 2021 Mr. Stanley Chapman Executive VP and President, U.S. Natural Gas Pipelines Great Lakes Gas Transmission Co 7000 Louisiana Street Houston, TX 77002 CPF 1-2021-042-WL Dear Mr. Chapman: From February 2, 2020 - May 21, 2020, representative from Michigan Public Service Commission (MI-PSC), 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 Great Lakes Gas Transmission Co (GLGT). On February 2, 2020, an incident occurred during normal operation of the Farewell Compressor Station in Clare County, MI. The pipeline and Farewell Compressor Station is owned and operated by GLGT. A technician responded to the sound of a presumed natural gas release and isolated the station by activating an Emergency Shut Down. The failure resulted in estimated cost of property damage and repairs exceeding the reportable threshold of $50,000. The pipeline was operating at 826 psig when the failure occurred, resulting in a release of approximately 1,500 standard cubic feet (mcf) of natural gas in total, with 672 mcf being unintended and 852 mcf being via controlled release. The failed 2-inch siphon drain line assembly and 36-inch header were examined via ultrasonic testing and magnetic particle non- destructive testing, and were later shipped to Texas for laboratory analysis. Metallurgical analysis determined that reversed bending fatigue from thermal lateral, and thermal expansion and contraction, caused the pipe to crack. The damage was isolated to the 2-inch siphon drain line assembly and associated 36-inch header. Farewell Compressor Station was returned to service on February 12, 2020 with permanent repairs completed on March 24, 2020.#

12021042WL_Warning Letter_05062021_(20-174444)_text.pdf, page 2CPF 1-2021-042-WL 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 investigated and the probable violation is: 1. § 192.161 Supports and anchors. (a) … (e) Each underground pipeline that is connected to a relatively unyielding line or other fixed object must have enough flexibility to provide for possible movement, or it must have an anchor that will limit the movement of the pipeline. GLGT failed to have enough flexibility to provide for possible movement or have an anchor that will limit the movement of an underground pipeline that is connected to a relatively unyielding line or other fixed object. Specifically, GLGT failed to provide enough flexibility within the 2- inch siphon drain line or restrain a 36-inch header at the inlet to the gas aftercooler at Farwell Compressor Station. During the investigation, the MI-PSC investigator reviewed GLGT’s as-built plans dated 1998. A concrete foundation was installed below the 36-inch header that encased a two-inch siphon’s weld- o-let connection. The 36-inch header was restrained vertically, but not restrained laterally to prevent thermal expansion and contraction, which resulted in failure of the fixed 2-inch siphon drain line weld-o-let. Therefore, GLGT failed to have enough flexibility to provide for possible movement or have an anchor that will limit the movement as prescribed in § 192.161(e). Under 49 U.S.C. § 60122 and 49 CFR § 190.223, you are subject to a civil penalty not to 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 violation 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. 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. 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 identified in this letter. Failure to do so will result in Great Lakes Gas Transmission Co being subject to additional enforcement action. No reply to this letter is required. If you choose to reply, in your correspondence please refer to CPF 1-2021-042-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 12021042WL_Warning Letter_05062021_(20-174444)_text Page 2 of 3#

12021042WL_Warning Letter_05062021_(20-174444)_text.pdf, page 3CPF 1-2021-042-WL 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 12021042WL_Warning Letter_05062021_(20-174444)_text Page 3 of 3#