FLINT HILLS RESOURCES, LC — Notice of Amendment

32026021NOA_Notice of Amendment_06182026_(26-369310)_text.pdf, page 1Official PDFU.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1100 Main Street, Suite 800 Kansas City, MO 64105 (816) 329-3800 NOTICE OF AMENDMENT VIA ELECTRONIC MAIL TO: francis.murphy@fhr.com June 18, 2026 Francis Murphy President and CEO Flint Hills Resources, LC 4111 East 37th Street North Wichita, KS 67220 CPF 3-2026-021-NOA Dear Mr. Murphy: From April 25, 2024 to May 3, 2024, and from June 10 to 12, 2024, a representative of the Pipeline and Hazardous Materials Safety Administration (PHMSA), Office of Pipeline Safety (OPS), pursuant to Chapter 601 of 49 United States Code (U.S.C.), conducted an investigation of the Clearbrook, Minnesota, Breakout Tank farm of Flint Hills Resources, LC (“FHR”). On Thursday, April 25, 2024, at 8:24 a.m. Central Daylight Time (CDT), an explosion occurred at FHR’s Clearbrook, Minnesota, Breakout Tank terminal, approximately 150 feet upstream of Tank 3, within an excavation in FHR’s Tank 8 diked area. The explosion occurred during maintenance activity to replace a 26-inch diameter buried bolted flanged tee on Line 151. The explosion was initiated as the result of a release of crude oil vapor from an inadequately sealed pipe plug installed at the open end of Line 151. The crude oil vapor was then ignited by the heat of an acetylene torch used to trim the pipe and prepare for welding a replacement tee. The explosion resulted in one injury that did not require overnight hospitalization. As a result of the investigation, PHMSA has identified the apparent inadequacy found within FHR’s plans or procedures. The item investigated and the inadequacy is described below: 1. § 195.402 Procedural manual for operations, maintenance, and emergencies. (a) . . . (c) Maintenance and normal operations. The manual required by paragraph (a) of this section must include procedures for the following to provide safety during maintenance and normal operations:#

32026021NOA_Notice of Amendment_06182026_(26-369310)_text.pdf, page 2(1) . . . (11) Minimizing the likelihood of accidental ignition of vapors in areas near facilities identified under paragraph (c)(4) of this section where the potential exists for the presence of flammable liquids or gases. FHR’s manual of written procedures for maintenance and normal operations was inadequate to provide safety when performing pipeline maintenance where the potential existed for the presence of flammable liquids and gases, as required by § 195.402(c)(11). Specifically, FHR’s procedures did not contain critical elements to minimize the likelihood of accidental ignition when preparing to perform hot work (for example, torch cutting and welding) in the presence of flammable crude oil gases. FHR’s O&M Hazardous Liquids Manual M1410.100 required a written procedure (Execution Plan) for the repair to be followed. PHMSA’s investigation found that neither the O&M manual nor the Execution Plan included specific procedures necessary for minimizing the likelihood of accidental ignition of vapors. PHMSA investigation found that the O&M manual and Execution Plan lacked the following critical elements necessary for safety to prevent accidental ignition of flammable gases. FHR’s written O&M manual and Execution Plan failed to include written block and bleed instructions to ensure that the valve VMOT 391A was sealed to isolate the work area from the potential for hazardous liquid to leak into Line 151 from Tank 3. A standard block and bleed test ensures there is no leakage occurring by requiring a valve to be simultaneously tested under pressure from both sides. It also requires the valve body to be fully drained (bled) using the bottom drain valve to visually verify seat integrity. In the absence of block and bleed instructions in the O&M manual or Execution Plan, FHR personnel performed an ad-hoc test of the valve with only low pressure from Tank 3 and failed to drain the valve body to ensure a complete seal on valve VMOT 391A. Consequently, the technician incorrectly interpreted a lack of oil flowing from a top port as confirmation of successful isolation from Tank 3. By not including specific, written instructions for a standard block and bleed test in its manual of written procedures, the procedures were inadequate to minimize the likelihood of accidental ignition of vapors in areas near facilities identified under § 195.402(c)(2) where the potential exists for the presence of flammable liquids or gases. Response 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 2#

32026021NOA_Notice of Amendment_06182026_(26-369310)_text.pdf, page 3document 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 thirty (30) 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 Flint Hills Resources, LC maintain documentation of the safety improvement costs associated with fulfilling this Notice of Amendment (preparation/revision of plans, procedures) and submit the total to the Director, Central Region, Pipeline and Hazardous Materials Safety Administration, Office of Pipeline Safety. In correspondence concerning this matter, please refer to CPF 3-2026-021-NOA and, for each document you submit, please provide a copy in electronic format whenever possible. Sincerely, AJ McKean Director, Central Region, Office of Pipeline Safety Pipeline and Hazardous Materials Safety Administration Enclosure: Response Options for Pipeline Operators in Enforcement Proceedings cc: Kelley Cabrera, Sr. Compliance Specialist, FHR, kelley.cabrera@fhr.com Matt McCauley, Compliance Director, FHR, matt.mccauley@fhr.com 3#