DTE GAS COMPANY — Notice of Amendment

party submissionOfficial PDF32025015NOA_Operator Response to Notice_06132025_(24-299898).pdf#

32025015NOA_Closure Letter_07072025_(24-299898)_text.pdf, page 1Official PDFVIA ELECTRONIC MAIL TO: Joi.Harris@dteenergy.com; Cedric.Flowers@dteenergy.com; Michael.Romein@dteenergy.com July 7, 2025 Mr. Joi Harris President and Chief Operating Officer DTE Gas Company One Energy Plaza WCB 2377 Detroit, MI 48226 RE: CPF 3-2025-015-NOA Dear Mr. Harris: From October 20 to November 10, 2024, representatives of the Michigan Public Service Commission, acting as an Interstate Agent for the Pipeline and Hazardous Materials Safety Administration (PHMSA), pursuant to Chapter 601 of 49 United States Code (U.S.C.), conducted an integrated inspection of DTE Gas Company’s (DTE) procedures and natural gas facilities on the Vector Pipeline System in Detroit, Michigan. On May 20, 2025, pursuant to 49 CFR § 190.206, PHMSA issued a Notice of Amendment which proposed amendment of DTE’s procedures. DTE submitted its amended procedures on June 13, 2025. PHMSA has reviewed the amended procedures, and it appears that the inadequacies outlined in the Notice of Amendment have been corrected. This letter is to inform you that no further action is necessary, and this case is now closed. Thank you for your cooperation. Sincerely, David Barrett Acting Director, Central Region, Office of Pipeline Safety Pipeline and Hazardous Materials Safety Administration cc: Mr. Cedric Flower, VP of Gas Operations, Cedric.Flowers@dteenergy.com Mr. Mike Romein; Manager of Gas Codes & Standards and Laboratory Services, Michael.Romein@dteenergy.com#

32025015NOA_Notice of Amendment_05202025_(24-299898)_text.pdf, page 1Official PDFNOTICE OF AMENDMENT VIA ELECTRONIC MAIL TO: Joi.Harris@dteenergy.com; Cedric.Flowers@dteenergy.com; Michael.Romein@dteenergy.com May 20, 2025 Mr. Joi Harris President and Chief Operating Officer DTE Gas Company One Energy Plaza WCB 2377 Detroit, MI 48226 CPF 3-2025-015-NOA Dear Mr. Harris: From October 20 to November 10, 2024, representatives of the Michigan Public Service Commission, acting as an Interstate Agent for the Pipeline and Hazardous Materials Safety Administration (PHMSA), pursuant to Chapter 601 of 49 United States Code (U.S.C.), conducted an integrated inspection of DTE Gas Company’s (DTE) procedures and natural gas facilities on the Vector Pipeline System in Detroit, Michigan. As a result of the inspection, PHMSA has identified the apparent inadequacies found within DTE’s plans or procedures. The items inspected and the inadequacies are described below: 1. § 192.463 External corrosion control: Cathodic protection. (a) Each cathodic protection system required by this subpart must provide a level of cathodic protection that complies with one or more of the applicable criteria contained in Appendix D of this part. If none of these criteria is applicable, the cathodic protection system must provide a level of cathodic protection at least equal to that provided by compliance with one or more of these criteria. Appendix D states: I. Criteria for cathodic protection – A. Steel, cast iron, and ductile iron structures. (1) A negative (cathodic) voltage of at least 0.85 volt, with reference to a saturated copper-copper sulfate half cell. Determination of this voltage must be made with the protective current applied, and in accordance with sections II and IV of this appendix.#

32025015NOA_Notice of Amendment_05202025_(24-299898)_text.pdf, page 2II. Interpretation of voltage measurement. Voltage (IR) drops other than those across the structure electrolyte boundary must be considered for valid interpretation of the voltage measurement in paragraphs A(1) and (2) and paragraph B(1) of section I of this appendix. DTE’s corrosion control standard 451, “Corrosion Control for Metallic Pipelines” (Standard 451), did not address how often DTE personnel are to conduct voltage (IR) drop surveys on DTE’s anode protected lines. Appendix D, section II, requires that IR drops other than those across the structure electrolyte boundary must be considered for valid interpretation of the voltage measurement in (A)(1) and (A)(2) of Appendix D. Section 4.10 of Standard 451 specified obtaining IR free readings (a method of considering IR drops) on DTE’s rectified systems every five years, but Standard 451 did not state how often DTE must do an IR free reading on its anode protected lines, such as the Vector line segment. Therefore, PHMSA proposes that DTE must revise its procedures to meet the requirements of § 192.463(a), in accordance with § 192.605(b)(2). 2. § 192.921 How is the baseline assessment to be conducted? (a) Assessment methods. An operator must assess the integrity of the line pipe in each covered segment by applying one or more of the following methods for each threat to which the covered segment is susceptible. An operator must select the method or methods best suited to address the threats identified to the covered segment (See § 192.917). (1) Internal inspection tool or tools capable of detecting those threats to which the pipeline is susceptible. The use of internal inspection tools is appropriate for threats such as corrosion, deformation and mechanical damage (including dents, gouges and grooves), material cracking and crack- like defects (e.g., stress corrosion cracking, selective seam weld corrosion, environmentally assisted cracking, and girth weld cracks), hard spots with cracking, and any other threats to which the covered segment is susceptible. When performing an assessment using an in-line inspection tool, an operator must comply with § 192.493. In addition, an operator must analyze and account for uncertainties in reported results (e.g., tool tolerance, detection threshold, probability of detection, probability of identification, sizing accuracy, conservative anomaly interaction criteria, location accuracy, anomaly findings, and unity chart plots or equivalent for determining uncertainties and verifying actual tool performance) in identifying and characterizing anomalies; DTE’s integrity management procedure, “ILI of Transmission Pipelines (13-SWI-011-0053),” for using in-line inspection (ILI) tools for assessments was not in accordance with §§ 192.921(a)(1) and 192.493. Section 192.493 incorporates by reference API RP 1163, “In-line Inspection Systems Qualification.” API RP 1163, section 8, “System Results Validation,” prescribes methods that shall be applied to validate if the reported inspection results meet or are within the performance specification for the pipeline being inspected. DTE’s procedure did not contain any guidance or specificity on how and when they would do this validation process. Therefore, PHMSA proposes that DTE must revise its integrity management procedures to meet the requirements of §§ 192.921(a)(1) and 192.493.#

32025015NOA_Notice of Amendment_05202025_(24-299898)_text.pdf, page 3Response to this Notice This Notice is provided pursuant to 49 U.S.C. § 60108(a) and 49 CFR § 190.206. Enclosed as part of this Notice is a document entitled Response Options for Pipeline Operators in Enforcement Proceedings. Please refer to this document and note the response options. 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). Following the receipt of this Notice, you have 30 days to submit written comments, revised procedures, or a request for a hearing under § 190.211. If you do not respond within 30 days of receipt of this Notice, this constitutes a waiver of your right to contest the allegations in this Notice and authorizes the Associate Administrator for Pipeline Safety to find facts as alleged in this Notice without further notice to you and to issue an Order Directing Amendment. If your plans or procedures are found inadequate as alleged in this Notice, you may be ordered to amend your plans or procedures to correct the inadequacies (49 CFR § 190.206). If you are not contesting this Notice, we propose that you submit your amended procedures to my office within 90 days of receipt of this Notice. This period may be extended by written request for good cause. Once the inadequacies identified herein have been addressed in your amended procedures, this enforcement action will be closed. It is requested (not mandated) that DTE Gas Company maintain documentation of the safety improvement costs associated with fulfilling this Notice of Amendment (preparation/revision of plans, procedures) and submit the total to Gregory A. Ochs, Director, Central Region, Pipeline and Hazardous Materials Safety Administration. In correspondence concerning this matter, please refer to CPF 3-2025-015-NOA and, for each document you submit, please provide a copy in electronic format whenever possible. Sincerely, David Barrett Acting Director, Central Region, Office of Pipeline Safety Pipeline and Hazardous Materials Safety Administration cc: Mr. Cedric Flower, VP of Gas Operations, Cedric.Flowers@dteenergy.com Mr. Mike Romein; Manager of Gas Codes & Standards and Laboratory Services, Michael.Romein@dteenergy.com Enclosure: Response Options for Pipeline Operators in Enforcement Proceedings#