ENABLE GAS TRANSMISSION, LLC — Warning Letter

12021031WL_Warning Letter_03252021_(20-173596)_text.pdf, page 1Official PDFWARNING LETTER OVERNIGHT EXPRESS DELIVERY March 25, 2021 Mr. Cary Watson Vice President Technical Services Enable Gas Transmission, LLC 499 W. Sheridan Ave., Suite 1500 Oklahoma City, OK 73102 CPF 1-2021-031-WL Dear Mr. Watson: On November 4, 5, and 18, 2020, a representative of the Pipeline and Hazardous Materials Safety Administration (PHMSA) pursuant to Chapter 601 of 49 United States Code (U.S.C.) inspected Enable Gas Transmission, LLC’s (EGT) Ruston underground natural gas storage facility in Lincoln County, Louisiana. As a result of the inspection, 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. § 192.12 Underground natural gas storage facilities. (a) … (b) Depleted hydrocarbon and aquifer reservoir UNGSFs. (1) … (2) Each UNGSF that uses a depleted hydrocarbon reservoir or an aquifer reservoir for natural gas storage and was constructed on or before July 18, 2017, must meet the provisions of API RP 1171 (incorporated by reference, see § 192.7), sections 8, 9, 10, and 11, and paragraph (c) of this section, by January 18, 2018, and must meet all provisions of paragraph (d) of this section by March 13, 2021. EGT failed to meet the provisions of API RP 1171, Section 8. Specifically, EGT did not properly evaluate the potential threats and hazards impacting storage wells in accordance with API RP 1171, Section 8.4.2 (Section 8.4.2).#

12021031WL_Warning Letter_03252021_(20-173596)_text.pdf, page 2CPF 1-2021-031-WL Section 8.4.2 states in part: The operator shall evaluate the potential threats and hazards impacting storage wells and reservoirs. The operator should refer to the list of common threats and hazards in Table 1 and may supplement the list in Table 1 with other hazards or threats identified by site-specific assessments. During the well site inspection, it was noted that a very large tree had recently fallen approximately 150 feet from a storage well location at Enable Mississippi River Transmission, LLC’s East Unionville storage field. EGT reported that falling trees were not included as a threat or hazard impacting its storage wells, even though multiple well locations at EGT’s Ruston storage field had large trees within falling distance of the wellheads. Therefore, EGT failed to meet the provisions of Section 8.4.2. 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 Enable Gas Transmission, LLC 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- 2021-031-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 12021031WL_Warning Letter_03252021_(20-173596)_text Page 2 of 2#