ENABLE MIDSTREAM PARTNERS, LP — Notice of Amendment

42021045NOA_Notice of Amendment_08112021_(21-201525)_text.pdf, page 1Official PDFNOTICE OF AMENDMENT ELECTRONIC MAIL - RETURN RECEIPT REQUESTED August 11, 2021 Cary Watson Vice President Safety, Environmental & Technical Programs Enable Midstream Partners, LP 499 West Sheridan Avenue, Suite 1500 Oklahoma City, Oklahoma 73102 CPF 4-2021-045-NOA Dear Mr. Watson: From May 18, 2021 through May 20, 2021, representatives of the Pipeline and Hazardous Materials Safety Administration (PHMSA) pursuant to Chapter 601 of 49 United States Code (U.S.C.), virtually inspected Enable Midstream Partners, LP’s (Enable) Integrity Management plans and procedures. Based on the inspection, PHMSA has identified the apparent inadequacies found within Enable’s plans or procedures as described below: 1. § 192.493 In-line inspection of pipelines. When conducting in-line inspections of pipelines required by this part, an operator must comply with API STD 1163, ANSI/ASNT ILI - PQ, and NACE SP0102, (incorporated by reference, see § 192.7). Assessments may be conducted using tethered or remotely controlled tools, not explicitly discussed in NACE SP0102, provided they comply with those sections of NACE SP0102 that are applicable. NACE SP0102 – 2017 5.1.5 Survey-acceptance criteria 5.1.5.1 A set of survey-acceptance criteria should be developed and agreed to by both parties prior to the start of the ILI survey. These criteria help to define when a rerun survey is required and include the following: 5.1.5.1.1 Physical damage to sensors after run… 5.1.5.1.6 Velocity underruns or overruns…#

42021045NOA_Notice of Amendment_08112021_(21-201525)_text.pdf, page 22. 3. Enable’s written Integrity Management Program, PS-248, ILI Service Provider Performance Specification (Effective Date 12/1/2020) is inadequate because it fails to provide the requirement in NACE SP0102-2010, Section 5: Logistical Guidelines, 5.1.5 Survey-acceptance criteria. The procedure failed to include a set of survey-acceptance criteria to define when a rerun survey was required. During the inspection, PHMSA reviewed Enable’s Integrity Management Program, PS- 248, ILI Service Provider Performance Specification, 4.0 Procedure, which stated: “6. The Company shall review the ILI Service Provider's acceptance criteria to ensure the following are met to define ILI re-runs based on the selected tool(s) capabilities:  Physical damage to sensors and sensor loss cannot exceed requirements of vendor reporting specifications” On May 21, 2021, Enable submitted to PHMSA a revised plan to address the requirements of § 192.493. Enable’s Integrity Management Program, PS-248, ILI Service Provider Performance Specification (Effective Date 5/21/2021) was reviewed by PHMSA and determined to be adequate. § 192.911 What are the elements of an integrity management program? (a)… (k) A management of change process as outlined in ASME/ANSI B31.8S, section 11. Enable did not have adequate procedures to address § 192.911(k) for its management of change process. PHMSA reviewed Enable’s written Integrity Management Program, PS- 165, IMP Management of Change (Effective Date 05/21/2020) and its Management of Change, MC-100 (Effective Date 11/19/2020) written procedures, which failed to include a required item from ASME B31.8S-2004, 11 Management of Change, specifically item (a)(8) regarding the qualification of staff. On May 28, 2021, Enable submitted to PHMSA a revised plan to address the requirements of § 192.911(k). Enable’s Integrity Management Program, PS-165, IMP Management of Change (Effective Date 5/27/2021) and Management of Change, MC-100 (Effective Date 5/27/2021) were reviewed by PHMSA and determined to be adequate. § 192.13 What general requirements apply to pipelines regulated under this part? (a)… (c) Each operator shall maintain, modify as appropriate, and follow the plans, procedures, and programs that it is required to establish under this part. 2#

42021045NOA_Notice of Amendment_08112021_(21-201525)_text.pdf, page 3Enable’s Corrosion Control, CC-262, Guided Wave Technology, Equipment Operation (Effective Date 5/9/2019) is inadequate because it fails to maintain, modify as appropriate, and follow the plans, procedures, and programs in accordance with § 192.13. Specifically, Enable failed to formally assign a procedure name and number for its Guided Wave Technology (GWT) procedure in part of its Notification Concerning Use of Other Technology: Application of guided wave ultrasound for integrity assessment of cased crossings (Revision 10, 1/8/2008). PHMSA reviewed Enable’s Corrosion Control, CC-262, Guided Wave Technology, Equipment Operation (Effective Date 5/9/2019) and its Application of guided wave ultrasound for integrity assessment of cased crossings (Revision 10, 1/8/2008) and found that the GWT procedure in the notification was a closer to complete version of the whole GWT process, but it did not have a formally assigned name or procedure number. Enable’s Corrosion Control, CC-262, Guided Wave Technology, Equipment Operation only addresses GWT equipment operation. On July 8, 2021, Enable submitted to PHMSA updated procedures: PS-278, Utilizing Other Technology for IM Assessments (Effective Date 07/07/2021) and PS-276, Other Technology – Guided Wave: Historic PHMSA Notification and Guidance Procedure (Effective Date 07/07/2021). Both procedures were reviewed by PHMSA and determined to be adequate. Response to this Notice This Notice is provided pursuant to 49 U.S.C. § 60108(a) and 49 C.F.R. § 190.206. Enclosed as part of this Notice is a document entitled Response Options for Pipeline Operators in Compliance 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. As mentioned above, Enable Midstream Partners, LP has already submitted revised procedures to PHMSA that reflect the amendments required by this Notice. These submitted procedures were reviewed and found to be adequate by PHMSA, therefore, no further action or response is required. If no additional response is received within 30 days of receipt of this Notice, this enforcement will be automatically closed. 3#

42021045NOA_Notice of Amendment_08112021_(21-201525)_text.pdf, page 4It is requested (not mandated) that Enable maintain documentation of the safety improvement costs associated with fulfilling this Notice of Amendment (preparation/revision of plans, procedures) and submit the total to Mary L. McDaniel, Director, Southwest Region, Pipeline and Hazardous Materials Safety Administration. In correspondence concerning this matter, please refer to CPF 4- 2021-045-NOA and, for each document you submit, please provide a copy in electronic format whenever possible. Sincerely, Mary McDaniel, P.E. Director, Southwest Region Pipeline and Hazardous Materials Safety Administration Enclosure: Response Options for Pipeline Operators in Enforcement Proceedings cc: Jimmy Cross, Senior Manager, DOT Compliance, Enable Midstream Partners, LP, jimmy.cross@enablemidstream.com Cary Windler, Director, GIS and Integrity Management, Enable Midstream Partners, LP, cary.windler@enablemidstream.com 4#