Algonquin Gas Transmission — Pipeline Special Permit

AGT Special Permit Analysis and Findings (SPAF), page 1Official PDFU.S. DEPARTMENT OF TRANSPORTATION PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION Special Permit Analysis and Findings Composite Pipe Special Permit Information: Docket Number: PHMSA-2025-0013 Requested By: Algonquin Gas Transmission, LLC Operator ID#: 00288 Original Date Requested: December 13, 2024 Original Issuance Date: March 12, 2026 Code Section(s): 49 CFR §§ 192.53(c), 192.121, 192.144, 192.149, 192.150, 192.619(a), 192.624, 192.710, and 192.714 Purpose: The Pipeline and Hazardous Materials Safety Administration (PHMSA), Office of Pipeline Safety (OPS), 1 provides this information to describe the facts of the subject special permit application submitted by Algonquin Gas Transmission, LLC (AGT)2 to discuss any relevant public comments received with respect to the application, to present the engineering and safety analysis of the special permit application, and to make findings regarding whether the requested special permit should be granted and, if so, under what conditions. Pipeline System Affected: On December 13, 2024, AGT applied for a special permit that would, in conjunction with enhanced integrity management practices, waive 49 Code of Federal Regulations (CFR) §§ 192.53(c), 192.121, 192.144, 192.149, 192.150, 192.619(a), 192.624, 192.710, and 192.714 for approximately 0.95 miles (5,040 feet) of 10.75 -inch diameter gas transmission pipeline named Line R-1 RSYS-EOLN in Hartford County, Connecticut. Special Permit Request: AGT’s special permit application specifically requested a waiver of 49 CFR §§ 192.53(c), 192.121, 192.144, 192.149, 192.150, 192.619(a), 192.624, 192.710, and 192.714 as applicable to 0.95 miles of pipe, comprising one pipeline special permit segment (SPS). Without this special permit, the applicable regulations would require AGT to inspect the existing steel pipeline segment for defects 1 Throughout this special permit the usage of “PHMSA” or “PHMSA OPS” means the U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration Office of Pipeline Safety. 2 AGT is owned by affiliates of Enbridge, Inc. PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit Analysis and Findings – Connecticut Page 1 of 4#

AGT Special Permit Analysis and Findings (SPAF), page 2using in-line inspection (ILI) tools and the segment would be subject to maximum allowable operating pressure (MAOP) reconfirmation under 49 CFR § 192.624 assessment requirements for Class 3 locations. As the existing steel pipeline segment is currently non-piggable—meaning the segment cannot be inspected for defects using conventional ILI tools—AGT applied for this special permit to allow them to insert Smartpipe3 into the existing steel pipeline, as opposed to repairing or replacing the pipe. As part of the application, AGT proposed to implement enhanced integrity management practices to provide an equivalent or better level of safety. Description and definition of the SPS and the pipeline specifications are detailed in “2025-0013 - AGT SP Application and Att A&B. ” Public Notice: On January 26, 2026, PHMSA posted a notice of this special permit request in the Federal Register (91 FR 3302) with a closing date of February 25, 2026. The AGT special permit application letter, Federal Register notice, environmental assessment, and all other pertinent documents are available for review in Docket No. PHMSA-2025-0013 in the Federal Docket Management System (FDMS) located at www.regulations.gov. PHMSA reviewed all public comments received for Docket Number PHMSA-2025-0013 through February 26, 2026. PHMSA received three public comment responses concerning this special permit request. Specific citations from the Federal pipeline safety regulations referenced throughout PHMSA’s responses to the public comments and are accessible online at eCFR: 49 CFR Chapter I Subchapter D – Pipeline Safety. 4 One anonymous commenter submitted a public comment response. The Pipeline Safety Trust (PST) and the Environmental Defense Fund (EDF) also submitted comments. PHMSA’s responses to each relevant comment are as follows. Summary of Public Comments: The commenters generally posed questions and concerns regarding the special permit application. PST’s comment generally provided questions about the circumstances and need for the permit, as well as the appropriateness of alternative conditions and the protective nature of the conditions in the permit. The purpose and unique circumstances of the special permit are described in AGT’s application included in the public notice. The special permit segment does not have the infrastructure to launch or receive ILI tools, and the special permit would enable AGT to address the MAOP reconfirmation applicability of the segment while reducing corrosion to the existing pipe, providing additional protection against third-party damage, and avoiding the environmental impact of pipe replacement. The special permit conditions include—among other safety measures—implementation of the manufacturer’s manuals and recommendations (section II), a hydrostatic pressure test (condition 1), and the use of integrity management for the special permit segment (condition 2(a)). The application of integrity management requirements to the special permit segment provides additional measures to 3 Smartpipe is a type of flexible reinforced thermoplastic pipe that is not authorized for use in regulated gas transmission pipelines under 49 CFR Part 192. 4 https://www.ecfr.gov/current/title-49/subtitle-B/chapter-I/subchapter-D PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit Analysis and Findings – Connecticut Page 2 of 4#

AGT Special Permit Analysis and Findings (SPAF), page 3ensure pipeline safety for the surrounding community. AGT’s integrity management approach, described in the Anticipated Integrity Management Overview document in the public notice, includes the anticipated use of continuous fiber optic monitoring for detecting leaks, temperature changes, and other integrity concerns to the special permit segment. The fiber optic network would be integrated into AGT’s supervisory control and data acquisition system. AGT’s overview, as well as the special permit conditions, also include long-term integrity assessments using direct assessment pipeline segments or equivalent measures. While AGT’s integrity management approach may be subject to change, the incorporation of the special permit segment into AGT’s integrity management program ensures PHMSA oversight and authority to ensure that integrity risks are addressed in accordance with applicable regulations. While the special permit contains fewer conditions than prior permits issued, PHMSA has endeavored to streamline its special permit process to focus on conditions that ensure that the special permit is consistent with pipeline safety while omitting other conditions, such as those which are duplicative of existing regulatory requirements. As a result, the special permit conditions provide an equivalent level of safety to compliance with the regulations. PST also inquired about the proposed effective dates of the special permit. While the effective date is unknown until PHMSA makes a final decision on an application, section III (7) of the draft special permit conditions included a special permit term of 15 years from issuance. PST also observed that the Docket contained a document titled, “Conditions: Final Approved 1/16” and questioned whether the special permit has already been approved. The file name in question was a drafting artifact, and the draft special permit conditions were publicly noticed prior to PHMSA’s final decision on the application in accordance with 49 CFR § 190.341. Lastly, both PST and EDF referenced the Notice of Limited Enforcement Discretion and Statement of Policy for Issuing Special Permits in Response to National Energy Emergency issued by PHMSA on January 12, 2026. AGT did not request that PHMSA consider its application in accordance with that Notice. Analysis: Background: Special permits may be granted upon request if unique circumstances make the applicability of a regulation or standard unnecessary or inappropriate for an applicant’s pipeline facility. Special permits will only be granted when the pipeline and the proposed special permit conditions will provide a level of safety greater than or equal to the code requirements. The operator’s Federal pipeline safety regulation compliance and incident history are also evaluated prior to issuance of a special permit. PHMSA reviewed this special permit request to understand the known type of integrity threats that are in the SPS. This integrity information informed the special permit conditions, which ensure that the operator has an ongoing program to locate and remediate safety threats. Enforcement History: In the last 5 years, PHMSA has taken two enforcement actions against AGT. 5 PHMSA’s review of the enforcement history for AGT does not indicate that granting the special permit would be inconsistent with pipeline safety. The enforcement data and reports used in the course of 5 See Federal Enforcement Data: AGT, PHMSA, https://primis.phmsa.dot.gov/enforcement-data/operator/288. PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit Analysis and Findings – Connecticut Page 3 of 4#

AGT Special Permit Analysis and Findings (SPAF), page 4PHMSA’s review are publicly available on PHMSA’s Enforcement Transparency website. The review included the enforcement history for AGT for the preceding 5-year period, which is also publicly available on PHMSA’s website. Incident History: In the last 5 years, AGT reported zero incidents. 6 PHMSA’s review of the incident history for AGT does not indicate that the granting of the special permit would be inconsistent with pipeline safety. The incident data used in the course of PHMSA’s review are publicly available on PHMSA’s Data Mart website. Findings: Based on the information submitted by AGT and PHMSA’s review of the documentation, PHMSA finds that granting this special permit with conditions that waives the requirements of 49 CFR §§ 192.53(c), 192.121, 192.144, 192.149, 192.150, 192.619(a), 192.624, 192.710, and 192.714 for AGT’s Line R-1 RSYS-EOLN pipeline SPS is not inconsistent with pipeline safety. This special permit requires AGT to implement the special permit conditions that include applying integrity management practices to the SPS. 6 To view this data, go to https://www.phmsa.dot.gov/data-and-statistics/pipeline/operator-information click on Operator Search link to search for Algonquin Gas Transmission, LLC and click on the “Incidents” tab. PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit Analysis and Findings – Connecticut Page 4 of 4#

AGT Special Permit LOD 3-12-2026, page 1Official PDF1200 New Jersey Avenue, S.E. Washington, D.C. 20590 U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration March 12, 2026 Peter Seydewitz Director, Operational Excellence Algonquin Gas Transmission, LLC 915 N. Eldridge Parkway Ste 1100 Houston, TX 77079 Re: Docket No. PHMSA-2025-0013 Special Permit Dates: March 12, 2026, to March 12, 2041 Dear Mr. Seydewitz: On December 13, 2024, Algonquin Gas Transmission, LLC (AGT), an entity owned by affiliates of Enbridge, Inc., applied to the Pipeline and Hazardous Materials Safety Administration (PHMSA) for a special permit pursuant to 49 Code of Federal Regulations (CFR) § 190.341. In its application, AGT asked PHMSA to waive certain requirements in the Federal pipeline safety regulations in 49 CFR Part 192 to allow Smartpipe1 to be inserted into an existing gas transmission pipeline segment in Hartford County, Connecticut, known as Line R-1 RSYS- EOLN. AGT proposed to implement enhanced integrity management practices to provide an equivalent or superior level of safety if PHMSA granted the application. PHMSA has reviewed the public comments and other information in the record and is issuing the enclosed special permit to AGT.2 The special permit waives the requirements in 49 CFR §§ 192.53(c), 192.121, 192.144, 192.149, 192.150, 192.619(a), 192.624, 192.710, and 192.714 for the Line R-1 RSYS-EOLN gas transmission pipeline segment and requires AGT to comply with conditions and limitations designed to maintain an equivalent level of pipeline safety. Please be advised that the special permit is subject to the requirements in 49 CFR § 190.341(j). If AGT elects not to implement the special permit conditions, AGT must notify PHMSA within 60 days and comply with 49 CFR § 192.53(c), 192.121, 192.144, 192.149, 192.150, 192.619(a), 192.624, 192.710, and 192.714 within 18 months of the date of this letter. 1 Smartpipe is a type of flexible reinforced thermoplastic pipe that is not authorized for use in regulated gas transmission pipelines under 49 CFR Part 192. 2 The special permit request letter, environmental assessment, special permit analysis and findings, and all other pertinent documents for this special permit addressing public comments are available in Docket No. PHMSA-2025-0013 in the Federal Docket Management System located at www.regulations.gov. https://www.regulations.gov/docket?D=PHMSA-2025-0013. Special Permit: PHMSA-2025-0013 Letter of Decision – Composite Pipe – Connecticut Page 1 of 2#

AGT Special Permit LOD 3-12-2026, page 2My staff would be pleased to discuss this special permit or any other regulatory matter with you. Any technical questions regarding this special permit should be directed to Max Kieba, Director, PHMSA, Engineering and Research Division, who may be contacted at 202-420-9169. Please direct any questions related to operational matters to Robert Burrough, Director of PHMSA Eastern Region, who may be contacted at 609-771-7809. Sincerely, LINDA GAIL DAUGHERTY Digitally signed by LINDA GAIL DAUGHERTY Date: 2026.03.12 09:31:01 -04'00' Linda Daugherty Acting Associate Administrator for Pipeline Safety Enclosure: Special Permit – PHMSA-2025-0013 Special Permit: PHMSA-2025-0013 Letter of Decision – Composite Pipe – Connecticut Page 2 of 2#

AGT Final Conditions - Composite Pipe Special Permit, page 1Official PDFU.S. DEPARTMENT OF TRANSPORTATION PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION SPECIAL PERMIT – Usage of Composite Pipe Special Permit Information: Docket Number: PHMSA-2025-0013 Requested By: Operator ID#: 00288 Original Date Requested: Original Issuance Date: Effective Dates: Code Section(s): Algonquin Gas Transmission, LLC December 13, 2024 March 12, 2026 March 12, 2026 to March 12, 2041 49 CFR §§ 192.53(c), 192.121, 192.144, 192.149, 192.150, 192.619(a), 192.624, 192.710, and 192.714 Proposed Grant of Special Permit: The Pipeline and Hazardous Materials Safety Administration (PHMSA), Office of Pipeline Safety (OPS),1 grants this special permit to Algonquin Gas Transmission, LLC (AGT or Operator),2 authorizing the use of Smartpipe3 on approximately 0.95 miles (5,040 feet) of the Line R-1 RSYS-EOLN in Hartford County, Connecticut. Line R-1 RSYS-EOLN is a non- piggable, 10.75-inch diameter steel gas transmission pipeline installed in 1967. I. Purpose and Need The maximum allowable operating pressure (MAOP) of Line R-1 RSYS-EOLN is currently 750 pounds per square inch gauge (psig). This special permit allows AGT to maintain that MAOP by waiving certain requirements in 49 Code of Federal Regulations (CFR) Part 192 and authorizing the use of Smartpipe on the portion of Line R-1 RSYS-EOLN that extends from milepost (MP) 0.00 to MP 0.95.4 The specific requirements that are waived include 49 CFR §§ 192.53(c), General; 192.121, Design of plastic pipe; 192.144, Qualifying metallic components; 192.149, Standard fittings; 192.150, Passage of internal inspection devices; 192.619(a), Maximum allowable operating pressure: Steel or plastic pipelines; 192.624, Maximum 1Throughout this special permit, the usage of “PHMSA” or “PHMSA OPS” means the U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration, Office of Pipeline Safety. 2 AGT is owned by affiliates of Enbridge, Inc. 3 Smartpipe is a type of flexible reinforced thermoplastic pipe that is not authorized for use in regulated gas transmission pipelines under 49 CFR Part 192. 4 The potential impact radius (PIR) for Line R-1 RSYS-EOLN is 204 feet and would not be increased if this special permit is granted. Five dwelling units are currently located within the PIR. PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit – Composite Pipe – Connecticut Page 1 of 4#

AGT Final Conditions - Composite Pipe Special Permit, page 2allowable operating pressure reconfirmation; 192.710, Transmission lines: Assessments outside of high consequence areas; and 192.714, Transmission lines: Repair criteria for onshore transmission pipelines. For purposes of this special permit, the term special permit segment (SPS) is defined as the composite pipe, fittings, monitoring devices, and related facilities that AGT is authorized to install on Line R-1 RSYS-EOLN from MP 0.00 to MP 0.95 subject to the conditions and limitations specified below. The request submitted by AGT and supporting documents can be found at Docket No. PHMSA-2025-0013 in the Federal Docket Management System located at www.regulations.gov. II. Conditions PHMSA grants this special permit subject to 49 CFR Part 191, 49 CFR Part 192, the Operator’s implementation of American Petroleum Institute (API) 15S Second Edition, manufacturer’s manuals and recommendations, and the following conditions.5 1) Design Factor and Pressure Test: Operate the SPS at or below an MAOP of 750 psig and a design factor of 0.449. Hydrostatically test all SPS pipe, connections, and appurtenances for a minimum of 12 hours at a minimum of 1.5 times the MAOP of the SPS consistent with the requirements of 49 CFR § 192.619 for pipe in a Class 3 location. This is not intended to require hydrostatic testing of casing pipe that is only designed to contain annular gases at well below the MAOP of the SPS. 2) Procedures: a) 3) Integrity Management: Incorporate the SPS into the Operator’s procedures as a “covered segment.” Not later than 60 days prior to construction, the Operator must develop all manuals, procedures, and specifications pertaining to the SPS unless otherwise specified below. b) Construction and Operator Qualifications: i) Develop procedures and implement an operator qualification (OQ) plan no less than 30 days prior to construction. The plan must specifically address composite pipe construction and operations and maintenance activities. The composite pipe shall be installed in one continuous section and must be constructed by OQ qualified Smartpipe Company, Inc., and AGT personnel. iii) Treat all SPS construction tasks as “covered tasks.” General Requirements: Ensure that there is no tapping, branch fittings, or splitting of the SPS composite pipe, except as required for repair. ii) 5 AGT must provide the Director of PHMSA Eastern Region with all information and documentation specified in this special permit, including when notification is required to PHMSA. If the specified PHMSA Region assignment changes, AGT will be notified to which Region they should direct their correspondence. PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit – Composite Pipe – Connecticut Page 2 of 4#

AGT Final Conditions - Composite Pipe Special Permit, page 3a) b) b) c) ii) In the event of a product recall or material defect pertaining to the composite pipe and end fitting products used in the SPS, the Operator will provide notification to PHMSA within 24 hours for discussion of mitigation. Pipe Damage: During the insertion process, the force on the composite pipe shall be monitored by use of a calibrated dynamometer, calibrated within 6 months of use. The maximum tensile force shall be limited to 73,000 pounds force. 4) Materials and Testing Requirements: a) The SPS high-density polyethylene PE4710 inner layer must be manufactured from natural gas pipe grade material. The SPS must not contain any regrind or rework material. Test reinforcement materials in accordance with API 15S Second Edition, and ASTM D5035. d) Perform long-term integrity assessments: i) Install seven or more segments in such a way that it simulates the condition of the SPS in the immediate vicinity of the operating pipeline at MP 0.95, on or near Operator property (direct assessment segments). Schedule and perform seven post-construction inspections at 12 months, 36 months, 60 months, 84 months, 108 months, 132 months, and 156 months after the completion of construction on direct assessment segments, with each inspection interval not exceeded by more than 90 days, and with focus on the composition and degradation of the pipe material through non-destructive and destructive testing. Destructive testing on direct assessment segments must include a hydrotest to burst pressure. iii) The Operator may propose to implement alternative provisions in the Smartpipe integrity management program for the SPS by written request to PHMSA, and with written approval by PHMSA prior to use. 5) Communication and Records: Design and Material Review: Notify and make available all design calculations, materials reviews, and certifications—including engineering assessments, processes, and calculations—used to establish the composite pipe MAOP 30 days prior to operating the pipeline. Construction Start: At least 60 days prior to construction, provide notification of the date, time, and location of pipeline installation and provide PHMSA an opportunity to witness the installation. III. Limitations This special permit is subject to the limitations set forth in 49 CFR § 190.341, as well as the following limitations: a) b) PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit – Composite Pipe – Connecticut Page 3 of 4#

AGT Final Conditions - Composite Pipe Special Permit, page 41) 2) 3) 4) 5) 6) 7) 8) PHMSA has the sole authority to make all determinations on whether the Operator has complied with the specified conditions of this special permit. Failure to comply with any condition may result in revocation of the special permit. Any procedures, plans, and associated schedules for the Line R-1 RSYS-EOLN SPS are automatically incorporated into this special permit and are enforceable in the same manner. Failure by the Operator to submit the certifications required for this SPS within the time frames specified may result in revocation of this special permit. This special permit is not applicable to Class 4 locations. As provided in 49 CFR § 190.341, PHMSA may issue an enforcement action for failure to comply with this special permit. The terms and conditions of any order issued by PHMSA applicable to a pipeline facility covered by this special permit will take precedence over the terms of this special permit. If the Operator sells, merges, transfers, or otherwise disposes of all or part of the assets known as the Line R-1 RSYS-EOLN pipeline in the SPS, the Operator must provide written notice of the change within 30 days of the consummation date. PHMSA grants this special permit to limit it to a term of no more than 15 years from the date of issuance. PHMSA reserves the right to revoke, suspend, or modify the special permit if a material change occurs in conditions or circumstances underlying the permit. AUTHORITY: 49 U.S. Code 60118 (c)(1) and 49 CFR § 1.97. Issued in Washington, D.C., on March 12, 2026. LINDA GAIL Digitally signed by LINDA GAIL DAUGHERTY DAUGHERTY Date: 2026.03.12 09:44:01 -04'00' Linda Daugherty, Acting Associate Administrator for Pipeline Safety PHMSA-2025-0013 – Algonquin Gas Transmission, LLC Special Permit – Composite Pipe – Connecticut Page 4 of 4#