{"operation":"document","citation":"DCA00MP004","title":"Hazardous Liquid Pipe Failure and Leak, Marathon Ashland Pipe Line, LLC","source_type":"incident","agency":"National Transportation Safety Board","status":"current","official":true,"published_on":"2026-01-30","effective_on":"2000-01-27","summary":"Accident. in Winchester, KY, USA. on 2000-01-27. Marathon Ashland Pipe Line LLC. Rupture/release","machine_formats":{"json":"https://regulus.evalyn.ai/document/ntsb-case-dca00mp004.json","markdown":"https://regulus.evalyn.ai/document/ntsb-case-dca00mp004.md"},"app_url":"https://regulus.evalyn.ai/document/ntsb-case-dca00mp004","source_url":"https://www.ntsb.gov/investigations/Pages/DCA00MP004.aspx","body":"NTSB investigation DCA00MP004.\n\nEvent Type: Accident\n\nEvent Date: 2000-01-27\n\nEvent City: Winchester\n\nEvent State Or Region: KY\n\nEvent Country: USA\n\nPipeline Operator: Marathon Ashland Pipe Line LLC\n\nPipeline Type: Hazardous Liquid - Regulated\n\nAccident Type: Rupture/release\n\nCompletion Status: Completed\n\nReport Number: PAB-01-02\n\nProbable cause: The probable cause of the accident was fatigue cracking due to a dent in the pipe that, in combination with fluctuating pressures within the pipe, produced high local stresses in the pipe wall. Contributing to the severity of the accident was the failure of the controller and supervisors to timely recognize the rupture, shut down the pipeline, and isolate the ruptured section of the pipeline.\n\nTier1Name: System shutdown\n\nTier2Name: Pipe structural malfunction/failure\n\nTier1Name: System operating\n\nTier2Name: System/equipment malf/failure\n\nTier1Name: Initiating product flow\n\nTier2Name: System warning/signal\n\nFinding Tier1Name: Personnel\n\nFinding Tier2Name: Action/decision\n\nFinding Tier3Name: Information processing/decision making\n\nFinding Modifier Name: SCADA operations personnel\n\nFinding Report Text: Personnel - Action/decision - Information processing/decision making - SCADA operations personnel\n\nFinding Tier1Name: Pipeline\n\nFinding Tier2Name: Pipeline structure\n\nFinding Tier3Name: Pipe\n\nFinding Modifier Name: Inadequate inspection\n\nFinding Report Text: Pipeline - Pipeline structure - Pipe - Inadequate inspection\n\nFinding Tier1Name: Pipeline\n\nFinding Tier2Name: Pipeline structure\n\nFinding Tier3Name: Pipe\n\nFinding Modifier Name: Damaged/degraded\n\nFinding Report Text: Pipeline - Pipeline structure - Pipe - Damaged/degraded\n\nOfficial NTSB investigation data. NTSB findings determine probable cause and make safety recommendations; they do not adjudicate civil liability or regulatory violations.\n\nWhat Happened\nAbout 12:12 p.m. CST on January 27, 2000, a Marathon Ashland Pipe Line LLC (Marathon Ashland) 24-inch-diameter pipeline that runs 265 miles between Owensboro and Catlettsburg, Kentucky, ruptured near Winchester, Kentucky. The ruptured pipeline released about 11,644 barrels (about 489,000 gallons) of crude oil onto a golf course and into Twomile Creek. No injuries or deaths resulted from the accident.\n\nWhat We Found\nWe determined the probable cause of the accident was fatigue cracking due to a dent in the pipe that, in combination with fluctuating pressures within the pipe, produced high local stresses in the pipe wall. Contributing to the severity of the accident was the failure of the controller and supervisors to timely recognize the rupture, shut down the pipeline, and isolate the ruptured section of the pipeline.\n\nPAB-01-02\n<<<PAGE 1>>>\n\nNational Transportation Safety Board\nWashington, D.C. 20594\nPipeline Accident Brief\nPipeline Accident Number: DCA-00-MP-004\nType of System: Hazardous liquid\nAccident Type: Pipe failure and leak\nLocation: Winchester, Kentucky\nDate and Time: January 27, 2000, 12:12 p.m. central standard\ntime (CST)\nOwner/Operator: Marathon Ashland Pipe Line LLC\nFatalities/Injuries: None\nDamage/Clean Up Cost: $7.1 million\nMaterial Released: Crude oil\nQuantity Released: About 489,000 gallons\nPipeline Pressure: 606 pounds per square inch, gauge, (psig)\nat site of failure\nComponent Affected: 24-inch-diameter, API 5L, X-52, 0.250-inch-wall-\nthickness, steel pipe\nThe Accident\nAbout 12:12 p.m. CST1 on January 27, 2000, a Marathon Ashland Pipe Line LLC\n(Marathon Ashland) 24-inch-diameter pipeline that runs 265 miles between Owensboro\nand Catlettsburg, Kentucky, ruptured near Winchester, Kentucky. The ruptured pipeline\nreleased about 11,644 barrels (about 489,000 gallons) of crude oil onto a golf course and\ninto Twomile Creek. No injuries or deaths resulted from the accident. As of\nDecember 13, 2000, Marathon Ashland had spent about $7.1 million in response to the\naccident.\nPreaccident Information\nThe pipe was 0.250-inch-wall-thickness, 24-inch-diameter, steel pipe. It was\nconstructed in 1973. In the area of the rupture, the pipeline ran through a layer of shale\nand rested on cinderblock-size pieces of Styrofoam. These Styrofoam “pillows” were\ninstalled to keep the pipe from lying directly on the shale. The pipeline had a maximum\noperating pressure of 780 psig.\n1 All references to time in this report are CST. Although the Marathon Ashland operations center is in\nthe eastern time zone (in Findley, Ohio), this pipeline originates in the CST zone.\nNTSB/PAB-01/02\n\n<<<PAGE 2>>>\n\n2\nIn January 1997, a contractor’s magnetic flux standard resolution inline inspection\ntool was run through the entire pipeline. Excavations were then made at locations along\nthe pipeline where the inspection tool indicated significant anomalies. At the site where\nthe pipeline ruptured, the 1997 inspection data showed an anomaly that the contractor had\ninterpreted as a “dent.” The pipeline had not been excavated at this location because the\ndent did not appear to meet the repair criteria being used at the time. The repair criteria\nused required that, for a dent to be repaired, it had to be deeper than 2 percent of the\noutside diameter of the pipe.\nLeak Reporting and Response\nDuring the morning of January 27, 2000, the pipeline had been shut down for\npreviously planned maintenance work at the Catlettsburg terminal. The shutdown of the\nline began at 6:59 a.m., and the line was out of operation until 11:12 a.m. At this time, a\ncontroller at the Marathon Ashland operations center in Findlay, Ohio, opened manifold\nvalves at Owensboro and Catlettsburg to allow the pipeline to return to normal\noperations.\nAt 11:14 a.m., the controller began to restart the pipeline. About 11:30 a.m., a\npipeline leak monitor (PLM) alarm sounded in the Findlay operations center and flashed\non the supervisory control and data acquisition (SCADA) screen.2 This alarm indicated\nthat the liquids into and out of the pipeline were not in balance. After the controller\nfocused on some pressure set points and flow rates to reestablish balance, he resumed\nstarting additional pumping units on the line. About 11:52 a.m., the SCADA system\nflashed “NORMAL” on the screen, indicating that the alarm had cleared and the flow\nrates were in balance. The controller continued to monitor pressures at stations along the\nline. At 12:00 noon, a PLM alarm again sounded, indicating that the parameters for the 2-\nhour and 4-hour line balance were still showing an imbalance on the system. (The\ncontroller explained during a postaccident interview that he had expected the PLM alarms\nto sound during the startup of the system, so he was not surprised by the alarms\nsounding.) SCADA records show that the pipeline rupture occurred between the\nMarathon Ashland Tates Creek and Preston Stations at approximately 12:12 p.m. A PLM\nalarm displayed almost immediately after the pipeline ruptured.\nAbout 12:37 p.m., the controller, uncomfortable about the lower-than-expected\npressures at pumping stations along the pipeline and a lost flow rate at Catlettsburg,\nstarted to shut the system down. Additional PLM alarms, showing losses, displayed at\n12:45 and 12:54 p.m.\n2 Pipeline controllers use the SCADA system to remotely monitor and control movement through pipelines. Using\nthe SCADA system, controllers can monitor flow rates and pressures along the lines and control valves and pumps to\nadjust the flow at pump stations and other locations throughout the pipeline system.\nNTSB/PAB-01/02\n\n<<<PAGE 3>>>\n\n3\nAbout 1:00 p.m., the controller paged the operations supervisor and, shortly\nafterwards, the supervisor came into the Findlay operations center. After the controller\nand the supervisor had discussed the situation and reviewed the data, they called the area\nsupervisor for this pipeline segment.\nThe two supervisors discussed the situation and agreed that they should pressure\nup the pipeline to monitor the pressures. The downstream valves at Catlettsburg were\nclosed about 1:02 p.m. About 1:28 p.m., a single pumping unit at Owensboro, the\noriginating pump station, was started to put pressure on the pipeline. Pressures along the\npipeline were observed and recorded. About 1:00, 1:38, 1:40, and 1:44 p.m., PLM alarms\nsounded and showed on the SCADA screen. At 1:46 p.m., and again at 1:57 p.m., the\npressures were recorded.\nAbout 2:00 p.m., the controller expressed concern to the operations supervisor\nthat they had put about 1,000 barrels of crude oil into the pipeline, but pressures were not\nrising as expected. After making a phone call to the area supervisor, the operations\nsupervisor told the controller to shut down the pipeline. The shutdown was accomplished\nabout 2:05 p.m.\nShortly afterwards, at 2:11 p.m., the Winchester Fire Department called the\npipeline operations center in Findlay, Ohio, to report the odor of gas in the air. The\noperations center immediately relayed this information to the area supervisor, who\ndispatched a four-person crew to close the two manual valves nearest the leak site.\nMarathon Ashland employees closed these manual valves at 3:30 p.m.\nAbout 2:20 p.m., a landowner downstream of the leak site telephoned the Findlay\noperations center to report oil flowing onto his property. The operations supervisor told\nthe controller to automatically shut the mainline block valves at the Preston and Tates\nCreek Stations.\nPostaccident Examination of the Failed Pipe\nThe rupture was found on the bottom of the pipe. (See figure 1.) Postaccident\nlaboratory examination of the pipe showed transgranular cracks that had the appearance\ntypical of fatigue progression. The combined depth of the progressive cracks in the areas\nof maximum penetration was about 90 to 95 percent of the pipe wall thickness.\nNTSB/PAB-01/02\n\n<<<PAGE 4>>>\n\n4\nFigure 1. Photograph of ruptured pipe; arrow indicates rupture site\nPrimary and secondary origin areas of fatigue cracking were found at the edges of\na dent in the pipe wall. The dent was consistent with contact with a hard object, although\nno hard object likely to have caused it (such as a rock) was found during the\ninvestigation. Numerous secondary cracks were in the vicinity of the two origin areas.\nPostaccident Developments\nAfter the accident, the U.S. Department of Transportation’s Research and Special\nPrograms Administration issued a Corrective Action Order requiring Marathon Ashland\n“to take the necessary corrective action to protect the public and the environment from\npotential hazards associated with its 24-inch pipeline.” In part, these actions included:\nmaintaining a 20-percent operating pressure reduction; conducting all analysis necessary\nto determine an interim maximum operating pressure; developing and implementing a\nwork plan for the testing and repair or replacement of sections of pipe with significant\ndefects; evaluating the effectiveness of full encirclement sleeves for repairing significant\ndefects identified by a transverse flux inline inspection tool; and submitting a report of\nthe results of all removal, testing, and analysis performed under the work plan to the\nregional director of the Office of Pipeline Safety. Marathon Ashland ran\nslope/deformation and transverse flux inspection tools in the pipeline and reported the\nfindings to the Office of Pipeline Safety. (These tools are used to discover anomalies in\nthe line, such as dents, corrosion, or cracking.) As a result of these internal inspections,\nanomalies meeting the repair criteria for the entire pipeline were reviewed, inspected, and\nrepaired.\nPostaccident Training\nBefore the spill, Marathon Ashland had allocated funds for and ordered (1) a\nSCADA training simulator for its controllers and (2) a full-time training supervisor. The\ntraining supervisor began duties in March 2000. The simulator arrived on May 15, 2000,\nNTSB/PAB-01/02\n\n<<<PAGE 5>>>\n\n5\nand the first pipeline simulation model, of a Marathon Ashland 10-inch products system,\nwas used to train 43 controllers. A second pipeline simulation, of a Marathon Ashland\n22-inch crude oil system, was installed on October 6, 2000. As of January 2001, four\ncontrollers had completed training on this second simulation. Marathon Ashland intends\nthe simulator training to help its controllers recognize and react to problems more\neffectively.\nProbable Cause\nThe probable cause of the accident was fatigue cracking due to a dent in the pipe\nthat, in combination with fluctuating pressures within the pipe, produced high local\nstresses in the pipe wall. Contributing to the severity of the accident was the failure of the\ncontroller and supervisors to timely recognize the rupture, shut down the pipeline, and\nisolate the ruptured section of the pipeline.\nApproved: May 3, 2001\nNTSB/PAB-01/02","truncated":false,"body_characters":12704}