{"operation":"document","citation":"PHMSA-2025-0455","title":"Rockies Express Pipeline, LLC — Pipeline Special Permit","source_type":"permit","agency":"Pipeline and Hazardous Materials Safety Administration","status":"current","official":true,"published_on":"2026-05-27","effective_on":"2026-05-27","summary":"PHMSA-2025-0455, issued 2026-05-27 for Rockies Express Pipeline, LLC's gas transmission system.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-special-permit-phmsa-2025-0455.json","markdown":"https://regulus.evalyn.ai/document/phmsa-special-permit-phmsa-2025-0455.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-special-permit-phmsa-2025-0455","source_url":"https://www.regulations.gov/docket/PHMSA-2025-0455","body":"PHMSA pipeline special permit PHMSA-2025-0455. Operator: Rockies Express Pipeline, LLC. System: Gas Transmission. Issue date: 2026-05-27.\n\n<<<PAGE 1>>>\n\nU.S. DEPARTMENT OF TRANSPORTATION\nPIPELINE AND HAZARDOUS MATERIALS SAFETY\nADMINISTRATION\nSPECIAL PERMIT – Alternative MAOP\nSpecial Permit Information:\nDocket Number: PHMSA-2025-0455\nRequested By: Rockies Express Pipeline, LLC\nOperator ID#: 32163\nOriginal Date Requested: July 18, 2025\nOriginal Issuance Date: May 27, 2026\nEffective Date: May 27, 2026\nCode Sections: 49 CFR § 192.620(b)(2), (b)(4), (b)(7), (c)(1), (c)(2), (c)(3),\n(c)(4), (c)(5), (c)(7), (d)(6), (d)(7)(i), (d)(7)(ii), (d)(7)(iii),\n(d)(9), (d)(11)(ii)(a), (d)(4)(v) and (d)(7)(iv)(B)\nGrant of Special Permit:\nBy this order, the Pipeline and Hazardous Materials Safety Administration (PHMSA), Office of\nPipeline Safety (OPS)1 grants this special permit to Rockies Express Pipeline, L.L.C. (REX).\n2\nThis special permit waives certain design, construction, and certification requirements in 49 Code\nof Federal Regulations (CFR) § 192.620, Alternative maximum allowable operating pressure for\ncertain steel pipelines, that would otherwise apply to the 2,886 gas transmission special permit\nsegments in the REX pipeline. These special permit segments currently operate at a maximum\nallowable operating pressure (MAOP) of 1,480 pounds per square inch gauge (psig) pursuant to\nwaivers granted by PHMSA in two previous orders.3 The waivers—originally issued prior to the\nadoption of the alternative maximum allowable operating pressure (AMAOP) requirements in 49\nCFR § 192.620—authorized the operation of special permit segments at an MAOP resulting in a\nhoop stress of up to 80 percent of the specified minimum yield strength (SMYS).\n1 Throughout this special permit, the use of “PHMSA” or “PHMSA OPS” means the U.S. Department of Transportation’s Pipeline and Hazardous\nMaterials Safety Administration Office of Pipeline Safety.\n2 Rockies Express Pipeline, L.L.C. (REX) is owned by Tallgrass Energy, L.P.\n3 Pursuant to PHMSA dockets PHMSA-2006-23998 and PHMSA-2022-0044.\nSpecial Permit – Alternative MAOP Acceptance Page 1 of 4\n\n<<<PAGE 2>>>\n\nSection 192.620 stipulates that operators must adhere to specific design, pressure testing, class\nlocation, and operations and maintenance (O&M) requirements to maintain an AMAOP. This\nspecial permit authorizes REX to continue operating the special permit segments as an AMAOP\npipeline under the conditions identified herein for Class 1 locations. It also grants permission to\noperate similarly in Class 2 locations that originally were designed and constructed for a hoop\nstress of up to 80 percent SMYS under the waiver granted in Docket No. PHMSA-2006-23998.\nI. Purpose and Need\nThe special permit would allow REX to operate mainline segments—originally designed and\nconstructed per Docket No. PHMSA-2006-23998—as an AMAOP pipeline in accordance with\n49 CFR §192.620 by waiving the following paragraphs of 49 CFR § 192.620: (b)(2), design\nrequirements; (b)(4), construction requirements; (b)(7), nondestructive examination; (c)(1),\nnotification; (c)(2), certification; (c)(3), certification delivery; (c)(4), strength testing; (c)(5),\noperations requirements; (c)(7), records retention; (d)(6), interference–external corrosion;\n(d)(7)(i), (d)(7)(ii), (d)(7)(iii), corrosion control indirect assessment; (d)(9), integrity baseline\nassessment; and (d)(11)(ii)(A), dent defect repair; and by implementing 49 CFR §\n192.620(d)(4)(v), damage prevention within 1 year; and (d)(7)(iv)(B), pipe-to-soil test stations in\nhigh consequence areas within 1 year. The 2006 waiver had similar requirements to the proposed\nsections of 49 CFR § 192.620 to be waived by this special permit but varied slightly as shown in\nAttachment E of Docket No. PHMSA-2025-0455.\nDocket No. PHMSA-2006-23998 allowed REX to operate certain segments of the REX pipeline\nat hoop stresses up to 80 percent of SMYS in Class 1 locations and at an MAOP of 1,480 psig.\nThe 46 waiver conditions included in Docket No. PHMSA-2006-23998 were a precursor to—\nand provided an equivalent level of safety to—the design, construction, operations, maintenance,\nand integrity management requirements later adopted in 49 CFR § 192.620.\nDocket No. PHMSA-2022-0044 allowed REX to waive compliance with 49 CFR § 192.611 for\nClass 1 to Class 2 location changes for 20 specific miles, totaling approximately 4.25 non-\ncontiguous miles of the REX pipeline originally operated under the 2006 waiver. Docket No.\nPHMSA-2022-0044 will be superseded and replaced by this special permit based on the class\nchange allowance granted by 49 CFR §§ 192.620(c)(8) and 192.611(a), which allow the REX\npipeline segments originally designed to operate at 80 percent of SMYS in Class 1 locations to\nbe upgraded one class.\nThis special permit will allow REX to continue safely operating mainline segments at hoop\nstresses up to 80 percent of SMYS pursuant to 49 CFR § 192.620 while waiving certain design,\nconstruction, and certification requirements. This special permit will create a unified and\nconsistent approach for managing the REX pipeline.\nII. Special Permit Segments and Inspection Areas\nThe request submitted by the operator and supporting documents can be viewed under Docket\nNo. PHMSA-2025-0455 in the Federal Docket Management System located at\nwww.regulations.gov. This special permit pertains to the 2,886 special permit segments and\ncorresponding special permit inspection areas identified in Attachment A. The special permit\nSpecial Permit – Alternative MAOP Acceptance Page 2 of 4\n\n<<<PAGE 3>>>\n\ncovers approximately 1,162 non-contiguous miles of interstate pipeline, extending from the\nCheyenne Compressor Station (latitude, longitude of approximately 40.947022, -104.796757) in\nWeld County, Colorado, to the Clarington Hub (latitude, longitude of approximately 39.831828,\n-80.877256) in Monroe County, Ohio. The special permit segments contain 42-inch steel\nmainline piping, operating at 1,480 psig with hoop stresses of up to 80 percent SMYS, installed\nunder the 2006 special permit, PHMSA-2006-23998. The REX pipeline segments that were\noriginally designed to operate at hoop stresses of up to 72 percent SMYS are not subject to the\nspecial permit. Maps of the REX pipeline are available at www.npms.phmsa.dot.gov. To search\nfor maps of the REX pipeline, select Use Public Map Viewer tool, search by State and county,\nand use the Query Tool to search by Operator ID to find REX pipelines operated in each county.\nIII. Conditions\nPHMSA grants this special permit subject to REX’s compliance with the following conditions.\nThese conditions must be implemented in addition to all applicable requirements of the Federal\npipeline safety regulations, except for the provisions in 49 CFR § 192.620 that are specifically\nwaived below:\n1) MAOP: REX will continue to operate at current MAOP of up to 1,480 psig.\n2) Notifications: REX must make all notifications required by 49 CFR §\n192.620, except to the extent compliance is waived by Condition 5 of this\nspecial permit, to PHMSA and State agents after the permit is granted.\n3) Procedures: REX must implement, develop, and modify all relevant\nprocedural changes necessary within 90 days of the granting of this special\npermit.\n4\n4) Record Requirements: REX must maintain records demonstrating compliance\nwith 49 CFR § 192.620, except to the extent compliance is waived by\nCondition 5 of this special permit, after the date of the issuance of the special\npermit.\n5) Operations and Maintenance: REX must operate the special permit segments\nas an AMAOP pipeline in compliance with the applicable safety standards in\n49 CFR § 192.620, with a waiver of the following design, construction, and\ncertification requirements of 49 CFR § 192.620 going forth from the date of\nthis permit:\na. 49 CFR § 192.620(b)(2), (b)(4), (b)(7), (c)(1), (c)(2), (c)(3), (c)(4),\n(c)(5), (c)(7), (d)(6), (d)(7)(i), (d)(7)(ii), (d)(7)(iii), (d)(9), (d)(11)(ii)(a),\nand\nb. 49 CFR § 192.620(d)(4)(v) and (d)(7)(iv)(B) to the extent they require\n4 REX must provide the Director, PHMSA Western Region, with all information and documentation specified in this special permit, including\nwhen notification is required to PHMSA. If the specified PHMSA Region assignment changes, REX will be notified to which Region it should\ndirect its correspondence.\nSpecial Permit – Alternative MAOP Acceptance Page 3 of 4\n\n<<<PAGE 4>>>\n\nimmediate implementation. Implementation shall be extended to 1 year\nof the issuance of the special permit.\nIV. Limitations\nThis special permit is subject to the limitations set forth in 49 CFR § 190.341, as well as the\nfollowing limitations:\n1. PHMSA has the sole authority to make all determinations on whether the operator has\ncomplied with the specified conditions of this special permit. Failure to comply with any\ncondition of this special permit may result in revocation of the special permit.\n2. Any procedures, plans, and associated schedules for the special permit segments are\nautomatically incorporated into this special permit and are enforceable in the same\nmanner.\n4. As provided in 49 CFR § 190.341, PHMSA may issue an enforcement action for failure\nto comply with this special permit. The terms and conditions of any order issued by\nPHMSA applicable to a pipeline facility covered by this special permit will take\nprecedence over the terms of this special permit.\n5. If the operator sells, merges, transfers, or otherwise disposes of all or part of the assets\nknown as the 42-inch diameter REX pipeline, extending from the Cheyenne Compressor\nStation in Weld County, Colorado, to the Clarington Hub in Monroe County, Ohio, the\noperator must provide written notice of the change within 30 days of the consummation\ndate.\n6. PHMSA grants this special permit for the operational life of the REX pipeline.\n7. PHMSA reserves the right to revoke, suspend, or modify the special permit if a material\nchange occurs in conditions or circumstances underlying the permit.\nAUTHORITY: 49 U.S. Code 60118(c)(1) and 49 CFR § 1.97.\nIssued in Washington, D.C., on May 27, 2026.\nLinda Daugherty\nActing Associate Administrator for Pipeline Safety\nSpecial Permit – Alternative MAOP Acceptance Page 4 of 4\n\n<<<PAGE 1>>>\n\nVia E-Mail\nMay 27, 2026\nCrystal Heter\nChief Operating Officer\nTallgrass Energy, L.P.\n370 Van Gordon Street\nLakewood, CO 80228\nRe: Docket No. PHMSA-2025-0455\nDear Ms. Heter:\nOn July 18, 2025, Rockies Express Pipeline, LLC (REX), an entity owned by Tallgrass Energy,\nL.P., applied to the Pipeline and Hazardous Materials Safety Administration (PHMSA) for a\nspecial permit pursuant to 49 Code of Federal Regulations (CFR) § 190.341. In its application,\nREX asked PHMSA to waive certain requirements in the Federal pipeline safety regulations in 49\nCFR Part 192 to allow the REX pipeline to continue to operate mainline segments, originally\ndesigned and constructed in accordance with special permit Docket No. PHMSA-2006-23998 as\nan alternative maximum allowable operating pressure (AMAOP) pipeline in compliance with 49\nCFR § 192.620. REX proposed implementing enhanced integrity management practices to\nprovide an equivalent or superior level of safety if PHMSA granted the application.\nPHMSA has reviewed the public comments and other information in the record and is issuing the\nenclosed special permit to REX. The special permit waives the requirements in 49 CFR\n§§ 192.620(b)(2), (b)(4), (b)(7), (c)(1), (c)(2), (c)(3), (c)(4), (c)(5),(c)(7), (d)(6), (d)(7)(i),\n(d)(7)(ii), (d)(7)(iii), (d)(9), (d)(11)(ii)(a), (d)(4)(v), and (d)(7)(iv)(B) for the REX gas\ntransmission pipeline special permit segments and requires REX to comply with conditions and\nlimitations designed to maintain an equivalent level of pipeline safety. This and other pertinent\ndocuments can be reviewed in Docket No. PHMSA-2025-0455 in the Federal Docket\nManagement System at www.regulations.gov.\n1\n1 https://www.regulations.gov/docket/PHMSA-2025-0455\nSpecial Permit: PHMSA-2025-0455\nLetter of Decision – AMAOP Page 1 of 2\n\n<<<PAGE 2>>>\n\nPlease be advised that the special permit is subject to the requirements in 49 CFR § 190.341(j).\nIf REX does not implement the special permit conditions, REX must notify PHMSA within\n60 days and comply with the entirety of 49 CFR § 192.620 within 18 months of the date of this\nletter.\nMy staff would be pleased to discuss this special permit or any other regulatory matter with you.\nFor technical matter, please contact Max Kieba, Director, Engineering and Research Division, by\ne-mail at pipelinespecialpermits@dot.gov. For compliance matters specific to this special permit,\nplease contact Dustin Hubbard, Director, Western Region, by e-mail at dustin.hubbard@dot.gov.\nSincerely,\nLinda Daugherty\nActing Associate Administrator for Pipeline Safety\nEnclosure: Special Permit – PHMSA-2025-0455\nSpecial Permit: PHMSA-2025-0455\nLetter of Decision – AMAOP Page 2 of 2\n\n<<<PAGE 1>>>\n\nJuly 21, 2026\nCrystal Heter\nPresident and Chief Executive Officer\nTallgrass Energy, L.P.\n370 Van Gordon Street\nLakewood, CO 80228\nRe: Docket No. PHMSA-2025-0455; Technical Correction\nDear Ms. Heter:\nOn May 27, 2026, the Pipeline and Hazardous Materials Safety Administration (PHMSA) issued\nto Rockies Express Pipeline, LLC (REX), an entity owned by Tallgrass Energy, L.P., a special\npermit pursuant to 49 Code of Federal Regulations (CFR) § 190.341. The special permit waives\ncertain requirements in 49 CFR § 192.620 for the REX gas transmission pipeline special permit\nsegments and requires REX to comply with conditions and limitations designed to maintain an\nequivalent level of pipeline safety. This and other pertinent documents can be reviewed in Docket\nNo. PHMSA-2025-0455 in the Federal Docket Management System at www.regulations.gov.\n1\nThis letter serves to inform you of a technical correction to the special permit. The special permit,\non page 2, refers to “20 specific miles, totaling approximately 4.25 non-contiguous miles of the\nREX pipeline.” This clause should properly read as “20 specific segments, totaling approximately\n4.25 non-contiguous miles of the REX pipeline.” This correction is consistent with the draft special\npermit as it was issued for public notice. No revised permit is forthcoming, and the original permit\nremains in effect.\nSincerely,\nMax Kieba\nDirector, Engineering and Research, Office of Pipeline Safety\n1 https://www.regulations.gov/docket/PHMSA-2025-0455\nSpecial Permit: PHMSA-2025-0455\nLetter of Decision – AMAOP Page 1 of 1\n\n<<<PAGE 1>>>\n\nU.S. DEPARTMENT OF TRANSPORTATION\nPIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION\nSpecial Permit Analysis and Findings\nAlternative MAOP\nSpecial Permit Information:\nDocket Number: PHMSA-2025-0455\nRequested By: Rockies Express Pipeline, LLC\nOperator ID#: 32163\nOriginal Date Requested: July 18, 2025\nOriginal Issuance Date: May 27, 2026\nCode Sections: 49 CFR §192.620(b)(2), (b)(4), (b)(7), (c)(1), (c)(2), (c)(3),\n(c)(4), (c)(5), (c)(7), (d)(6), (d)(7)(i), (d)(7)(ii), (d)(7)(iii),\n(d)(9), (d)(11)(ii)(a), (d)(4)(v) and (d)(7)(iv)(B)\nPurpose:\nThe Pipeline and Hazardous Materials Safety Administration (PHMSA), Office of Pipeline Safety\n(OPS)1 provides this information to describe the facts of the subject special permit application\nsubmitted by Rockies Express Pipeline, LLC (REX),\n2 to discuss any relevant public comments received\nwith respect to the application, to present the engineering and safety analysis of the special permit\napplication, and to make findings justifying the requested special permit being granted.\nPipeline System Affected:\nOn July 18, 2025, REX applied for a special permit that would, in conjunction with enhanced integrity\nmanagement (IM) practices, waive 49 Code of Federal Regulations (CFR) § 192.620(b)(2), (b)(4),\n(b)(7), (c)(1), (c)(2), (c)(3), (c)(4), (c)(5), (c)(7), (d)(6), (d)(7)(i), (d)(7)(ii), (d)(7)(iii),\n(d)(9), (d)(11)(ii)(a), (d)(4)(v), and (d)(7)(iv)(B) for approximately 1,162 non-contiguous miles of the\n1 Throughout this special permit, the use of “PHMSA” or “PHMSA OPS” means the U.S. Department of Transportation’s Pipeline and Hazardous\nMaterials Safety Administration Office of Pipeline Safety.\n2 Rockies Express Pipeline, L.L.C. (REX) is owned by Tallgrass Energy.\nPHMSA-2025-0455 – Rockies Express Pipeline, LLC Special Permit Analysis and Findings\nPage 1 of 5\n\n<<<PAGE 2>>>\n\n42-inch diameter natural gas transmission REX pipeline from the Cheyenne Compressor Station in\nWeld County, Colorado, to the Clarington Hub in Monroe County, Ohio.\nSpecial Permit Request:\nREX requested that PHMSA allow REX to continue to operate mainline segments, originally designed\nand constructed per special permit Docket No. 2006-23998, as an alternative maximum allowable\noperating pressure (AMAOP) pipeline prior to the adoption of the AMAOP requirements in 49 CFR §\n192.620. This special permit waives the following paragraphs of 49 CFR § 192.620: (b)(2), design\nrequirements; (b)(4), construction requirements; (b)(7), nondestructive examination; (c)(1), notification;\n(c)(2), certification; (c)(3), certification delivery; (c)(4), strength testing; (c)(5), operations\nrequirements; (c)(7), records retention; (d)(6), interference – external corrosion; (d)(7)(i), (d)(7)(ii),\n(d)(7)(iii), corrosion control indirect assessment; (d)(9), integrity baseline assessment; and\n(d)(11)(ii)(A), dent defect repair; and implements 49 CFR § 192.620(d)(4)(v), damage prevention; and\n(d)(7)(iv)(B), pipe-to-soil test stations in high consequence areas within 1 year. This special permit\nsupersedes the 2006 waiver as well as Docket No. PHMSA-2022-0044, which allowed REX to waive\ncompliance with 49 CFR § 192.611 for Class 1 to Class 2 location changes for 20 specific segments,\ntotaling approximately 4.25 non-contiguous miles of the REX pipeline originally operated under the\n2006 waiver.\nPipe descriptions and specifications for the 2,886 special permit segments are detailed in Attachment A\nin Docket No. PHMSA-2025-0455.\nPublic Notice:\nOn February 9, 2026, PHMSA posted a notice of this special permit request in the Federal Register\n(91 FR 5803) with a closing date of March 11, 2026. The special permit application letter, Federal\nRegister notice, environmental assessment, and all other pertinent documents are available for review in\nDocket No. PHMSA-2025-0455 in the Federal Docket Management System located at\nwww.regulations.gov.\nPHMSA reviewed all public comments received for Docket No. PHMSA-2025-0455 through March\n11, 2026. PHMSA received three public comments concerning this special permit request that are\naddressed below in the public comment summary. On March 20, 2026, PHMSA also received a\nsupplemental letter from REX regarding submitted public comments, which is included in the docket as\nAttachment B. Specific citations from the Federal pipeline safety regulations 49 CFR Part 190 and\nPart 192 are referenced throughout PHMSA’s responses to the public comments and are accessible\nonline at eCFR: 49 CFR Chapter I Subchapter D – Pipeline Safety.\n3\nSummary of Public Comments:\nPHMSA received a total of three public comments—from the Pipeline Safety Trust (PST), the\nEnvironmental Defense Fund (EDF), and one anonymous source. The anonymous source comment was\nnot relevant to the special permit request. Tallgrass also submitted a comment to PHMSA directly,\nwhich will be posted to the docket upon publication of the permit.\n3 https://www.ecfr.gov/current/title-49/subtitle-B/chapter-I/subchapter-D\nPHMSA-2025-0455 – Rockies Express Pipeline, LLC Special Permit Analysis and Findings\nPage 2 of 5\n\n<<<PAGE 3>>>\n\nPST raised questions about the evolution over time of the class locations along the pipeline and\nencouraged the use of safety measures in Class 1 locations even though they tend to be less populated.\nPHMSA notes that the requirement in the special permit for the use of AMAOP IM applies to the\nentirety of the pipeline, including Class 1 locations. This directly address the concern raised in PST’s\ncomment about protecting less populated Class 1 locations along the line. While population growth\nalong pipelines is always subject to change, REX will continue to be required by the regulations to\nmaintain continuous surveillance of its facilities to identify and address class changes and adjust its\nsafety measures accordingly. In addition, this special permit maintains the 80 percent of specified\nminimum yield strength (SMYS) limit for Class 2 locations and does not extend to Class 3 location\nchanges.\nIn addition, PST questioned the special permit’s term for the operational life of the pipeline and asked\nwhether periodic re-evaluations or automatic permit modification were warranted. PHMSA notes that\ndesign and construction requirements, such as those in 49 CFR § 192.620, cannot simply be\nretroactively satisfied at a future date. Granting a permit for the operational life of the pipeline is\nreasonable and obviates the need for perpetual renewals. The 2006 waiver also did not have a defined\ntermination date or renewal requirement. REX’s compliance with the special permit conditions, as well\nas its compliance with other applicable regulations, will be addressed through PHMSA’s inspection and\nenforcement program, which includes evaluations of operator maintenance, operations, and records to\nconfirm compliance.\nPST raised several other requests for additions to the permit, including the public auditing of special\npermit compliance, annual reporting of certain data to PHMSA and State agencies, and triggers for\npermit revocation. These concerns are addressed through PHMSA’s inspection program, the revocation\ncriteria in 49 CFR § 190.341, and other applicable reporting criteria already in Federal pipeline safety\nregulations. For example, the AMAOP regulations address such issues as public notification (49 CFR §\n190.620(d)(2)) and right-of-way protection (49 CFR § 192.620(d)(4)), and REX will continue to\nimplement these measures on the pipeline as part of the special permit.\nPST also raised a question about the special permit’s one-year grace period for compliance with 49\nCFR § 192.620(d)(4)(v) and (d)(7)(iv). PHMSA notes that the grace period allows REX to transition\nfrom the Common Ground Alliance Best Practices, which it implemented in accordance with the 2006\nwaiver, and the requirements under 49 CFR § 192.620(d)(4)(v), which are slightly different and require\ndifferent documentation.\nPST also raised several location-specific questions, including questions regarding class changes\nspecific to Ohio and a particular cluster of corrosion anomalies, and requested additional special permit\nconditions for both. PHMSA notes the special permit conditions were designed to harmonize REX’s\n2006 waiver and 49 CFR § 192.620, which was promulgated after the waiver was issued to REX. Both\nthe waiver and 49 CFR § 192.620 include enhanced IM procedures, requiring REX to address all\nintegrity threats to the pipeline. The proposed special permit does not change these requirements. The\nIM measures, which are part of PHMSA’s standard regulatory structure, are well-designed to address\ncorrosion issues and, in conjunction with any required class changes, address risks arising from\npopulation growth near the pipeline. Based on the conditions proposed in the draft special permit,\nPHMSA has determined that the permit is consistent with pipeline safety.\nPHMSA-2025-0455 – Rockies Express Pipeline, LLC Special Permit Analysis and Findings\nPage 3 of 5\n\n<<<PAGE 4>>>\n\nLastly, both PST and EDF referenced the Notice of Limited Enforcement Discretion and Statement of\nPolicy for Issuing Special Permits in Response to National Energy Emergency issued by PHMSA on\nJanuary 12, 2026. REX did not request that PHMSA consider its application in accordance with the\nprovisions of the Notice, which is not relevant to the special permit issued in this proceeding.\nAnalysis:\nBackground: REX constructed this pipeline between 2005 and 2009. PHMSA issued a waiver on July\n11, 2006, allowing REX to operate certain segments of the REX pipeline at a hoop stress up to\n80 percent of SMYS in Class 1 locations and at a maximum allowable operating pressure (MAOP) of\n1,480 pounds per square inch (Docket No. PHMSA-2006-23998, referenced herein as “2006 waiver”).\nThe 2006 waiver also: (1) grants the REX pipeline relief from equipment requirements for pressure\nrelieving and limiting stations, and (2) contains 46 “waiver conditions.” The waiver conditions were\nadditional requirements exceeding those established in 49 CFR Part 192, and addressed aspects of\npipeline design, construction, operations and maintenance, reporting, and IM. The requirements\nprovided a higher level of pipeline safety relative to pipelines operated under the typical regulations in\nplace at the time as prescribed in 49 CFR Part 192. The REX pipeline was designed, constructed, and\noperated under these waiver conditions from 2006 through the effective date of this special permit.\nTwo years later, PHMSA adopted 49 CFR § 192.620, “Alternative maximum allowable operating\npressure for certain steel pipelines” (“AMAOP Rule”). Pipeline Safety: Standards for Increasing the\nMaximum Allowable Operating Pressure for Gas Transmission Pipelines, 73 Fed. Reg. 62,148 (Oct.\n17, 2008). The new AMAOP Rule allowed for operation of pipelines at an MAOP corresponding to\npercentage of SMYS greater than previously allowed by 49 CFR Part 192. The AMAOP Rule further\nestablished a process for managing the life cycle of a pipeline operating at a higher stress level based on\nexperience with the waivers/special permits. As noted in the preamble to the AMAOP Rule, the\nrequirements of the AMAOP Rule were established to codify the terms and conditions in the waivers,\nincluding the 2006 waiver, issued by PHMSA prior to publishing the AMAOP Rule. As such, the 2006\nwaiver conditions were a precursor to the design, construction, and operations and maintenance\nrequirements contained in 49 CFR § 192.620.\nIn 2022, PHMSA issued REX Special Permit PHMSA-2022-0044 to waive compliance with 49 CFR\n§ 192.611 for Class 1 to Class 2 location changes for 20 specific segments, totaling approximately\n4.25 non-contiguous miles of the REX pipeline, originally operated under the 2006 waiver. The 2022\nspecial permit was requested because the 2006 waiver did not contemplate these types of class location\nchanges, which are allowed on pipelines constructed under 49 CFR § 192.620. This special permit\nsupersedes the 2006 waiver, as well as Docket No. PHMSA-2022-0044.\nEnforcement History: In the last 5 years, PHMSA has taken seven enforcement actions against REX.\n4\nSome of the prior enforcements concern matters, including class location, that are addressed by the\nrequirements of this special permit. In the last 5 years, PHMSA has also taken 10 enforcement actions\nagainst Tallgrass Energy,\n5 which owns REX. PHMSA did not identify these enforcement matters as\nlikely to render the special permit conditions ineffective or inappropriate. PHMSA’s review of the\nenforcement history for REX does not indicate that granting the special permit would be inconsistent\n4 See Federal Enforcement Data: REX, PHMSA, https://primis.phmsa.dot.gov/enforcement-data/operator/32163\n5 See Federal Enforcement Data: Tallgrass Energy, PHMSA, https://primis.phmsa.dot.gov/enforcement-data/operator/1007\nPHMSA-2025-0455 – Rockies Express Pipeline, LLC Special Permit Analysis and Findings\nPage 4 of 5\n\n<<<PAGE 5>>>\n\nwith pipeline safety. The enforcement data and reports used during PHMSA’s review are publicly\navailable on PHMSA’s Enforcement Transparency website.\nIncident History: In the last 5 years, REX reported four incidents.6 PHMSA did not identify these\nprior incidents as likely to render the special permit conditions ineffective or inappropriate. PHMSA’s\nreview of the incident history for REX does not indicate that the granting of the special permit would\nbe inconsistent with pipeline safety. The incident data used during PHMSA’s review is publicly\navailable on PHMSA’s Data Mart website.\nFindings:\nBased on the information submitted by REX and PHMSA’s review of the documentation, PHMSA\nfinds that granting this special permit with conditions that waives the requirements of 49 CFR\n§ 192.620(b)(2), (b)(4), (b)(7), (c)(1), (c)(2), (c)(3), (c)(4), (c)(5),(c)(7), (d)(6), (d)(7)(i), (d)(7)(ii),\n(d)(7)(iii), (d)(9), (d)(11)(ii)(a), (d)(4)(v), and (d)(7)(iv)(B) on the special permit segment of the REX\npipeline system is not inconsistent with pipeline safety. This special permit requires REX to implement\nthe special permit conditions that include applying integrity management practices to the special permit\nsegment.\nCompleted in Washington, D.C., on: May 27, 2026\nPrepared by: PHMSA – Engineering and Research Division\n6 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 Rockies\nExpress Pipeline, LLC, and click on the “Incidents” tab.\nPHMSA-2025-0455 – Rockies Express Pipeline, LLC Special Permit Analysis and Findings\nPage 5 of 5","truncated":false,"body_characters":29100}