"HOLLY ENERGY PARTNERS - OPERATING, L.P."

Incident Narrative

"ON AUGUST 1, 2025, AT APPROXIMATELY 9:04 A.M. CDT, TECHNICIANS ARRIVED AT THROCKMORTON STATION TO PERFORM SCHEDULED PIGGING ACTIVITIES. UPON ARRIVAL, THEY DISCOVERED A LEAK ORIGINATING FROM MAINLINE PUMPING UNIT #2. TECHNICIANS IMMEDIATELY NOTIFIED THE QUALIFIED INDIVIDUAL (QI), WHO IN TURN CONTACTED THE ARTESIA CONTROL CENTER. THE PIPELINE WAS SHUT DOWN BY STOPPING ALL MAINLINE PUMPING UNITS AND CLOSING ALL ASSOCIATED MOTOR OPERATED VALVES (MOVS) ON THE SYSTEM. WHILE THE SHUTDOWN WAS IN PROGRESS, TECHNICIANS OBSERVED PRODUCT BEGINNING TO FLOW OUTSIDE THE STATION BOUNDARIES AND ONTO THE PIPELINE RIGHT-OF-WAY. USING SHOVELS, THEY QUICKLY CONSTRUCTED AN EARTHEN BERM TO PREVENT FURTHER MIGRATION OF PRODUCT. ONCE THE PIPELINE WAS FULLY ISOLATED, THE TECHNICIANS BLOCKED OUT BOTH PUMPING UNITS AND PLACED COLLECTION BUCKETS UNDER THE RELEASE POINT TO CAPTURE RESIDUAL FLOW. THESE EFFORTS WERE SLOWED DUE TO HAZARDOUS VAPORS, REQUIRING THE USE OF AIR MONITORING EQUIPMENT TO CONTINUE SAFELY WITH LOCKOUT/TAGOUT PROCEDURES. REMEDIATION ACTIVITIES BEGAN IMMEDIATELY, AIDED BY A VACUUM TRUCK ALREADY ONSITE FOR THE PLANNED PIGGING OPERATIONS. SUBSEQUENT INSPECTION DETERMINED THE FAILURE ORIGINATED FROM A 1/2-INCH STAINLESS STEEL TUBING LINE ON THE SUCTION SIDE OF PUMP UNIT #2, WHICH HAD CRACKED APPROXIMATELY ONE INCH FROM THE TUBING FERRULE. THE INITIALLY REPORTED RELEASE VOLUME OF 155 BARRELS OF GASOLINE WAS LATER CORRECTED TO 75 BARRELS OF JET FUEL. FREE PRODUCT WAS RECOVERED, AND CONTAMINATED SOIL THAT COULD BE SAFELY ACCESSED WAS EXCAVATED AND STAGED FOR OFFSITE DISPOSAL. THE FAILED TUBING WAS SENT TO SWAGELOK FOR METALLURGICAL EVALUATION, WHICH CONCLUDED THE TUBING FAILED DUE TO FATIGUE, LIKELY CAUSED BY FLOW-INDUCED VIBRATION AND INSUFFICIENT SUPPORT NEAR ROTATING EQUIPMENT. THE TUBING MET MATERIAL HARDNESS SPECIFICATIONS (HRB 81) AND SHOWED NO WORKMANSHIP DEFICIENCIES. SWAGELOK