Failure Report- Columbia Gas Transmission 11/5/08

Page 1Official PDFFailure Investigation Report – Columbia Gas Transmission Rupture – Activity ID 122980 Principal Investigator Dave McMillan, PHMSA ER Regional Director Byron Coy Date of Report 2/18/2011 Subject Failure Investigation Report – Columbia Gas Transmission Pipeline Rupture Summary: On November 5, 2008, at approximately 2:10 p.m., Columbia Line 1278 failed near Milford, PA, during an uprating procedure to increase the pressure in the line from a reduced 800 psig operating pressure back to the original 1000 psig MAOP of the pipeline. Columbia had recently been given authorization by PHMSA to increase the pressure in the pipeline back to the original MAOP after demonstrating that the integrity of the pipeline was adequate. The pipeline failure resulted in a rupture that involved three lengths of pipe in a wetland area. The failure occurred in the northern portion of the pipeline between Weber Road, Pike County, PA and Millrift, PA, 46 miles from the upstream compressor station at Easton, PA. Pressure in the pipeline had been increased from 800 psig to 1000 psig in 50 psig increments. The operator then began to reduce the pressure, and at 986 psig the pipeline failed. There were no injuries. There was no ignition of gas. Valves were shut in both directions. No customers had service interrupted as a result of the pipeline failure. The failure occurred in a rural area. After the failed section was isolated, Columbia began its investigation of the incident and its remediation to restore the line to service. Columbia installed 510 feet of new 14-inch, coated, steel pipeline in the wetland area to replace the pipe that failed. On December 6, 2008, service was restored in the pipeline. The failed section of pipe separated into four pieces. These pieces along with several other segment of the pipeline were visually examined and analyzed by Kiefner and Associates, Inc. The lab tests results indicated that the failure was caused by near-neutral-pH stress corrosion cracking (SCC). This has been noted in the company reported apparent cause in Part G of Appendix 3. Columbia pipeline 1278 runs from the Maryland/Pennsylvania state border to the Pennsylvania/NewYork state border. The pipeline was constructed in 1948. Over several years beginning in 2002, the pipeline went through a rehabilitation and replacement project due to a Corrective Action Order issued by the Department of Transportation due to a previous incident with the pipeline and the discovery of extensive external corrosion. The CAO required that the pressure in the pipeline be reduced from its original MAOP of 1000 psig to 600. The pressure was subsequently approved by PHMSA to be increased to 800 psig based on the findings of an inspection of the pipeline using an in-line inspection device. 122980 Summary DM CGT 2616 Easton 2901 Line 1278 I03 11052008.docx Page 1 of 4#

Page 2Failure Investigation Report – Columbia Gas Transmission Rupture – Activity ID 122980 Operator, Location, & Consequences Date & Time of Failure: 11/5/2008 Commodity Released: Natural Gas City/County & State: Milford Township, PA OpID & Operator Name 2616 Columbia Gas Transmission Corporation Unit # & Unit Name 2901 Easton Field Office-PA SMART Activity #: 122980 Milepost / Location ½ mile at the intersection North of I84 and Route 6 Lat: 41.33269870 Long: 74.84080223 Type of Failure: Rupture Fatalities: 0 Injuries 0 Description of area impacted Rural Property damage Gas loss $164,000 Property Damage $1,685,692 122980 Summary DM CGT 2616 Easton 2901 Line 1278 I03 11052008.docx Page 2 of 4#

Page 3Failure Investigation Report – Columbia Gas Transmission Rupture – Activity ID 122980 System Details The Line 1278 System traverses the eastern counties of Pennsylvania beginning in Lancaster County and ending in Pike County. The Line 1278 system totals 146.5 miles, consisting of 14” and 20” pipe. Gas flow is predominantly south to north. Events Leading up to the Failure Over several years beginning in 2002, the pipeline went through a rehabilitation and replacement project due to a Corrective Action Order issued by the Department of Transportation due to a previous incident with the pipeline and the discovery of extensive external corrosion. The CAO required that the pressure in the pipeline be reduced from its original MAOP of 1000 psig to 600. The pressure was subsequently approved by PHMSA to be increased to 800 psig based on the findings of an inspection of the pipeline using an in-line inspection device. On November 5, 2008, at approximately 2:10 p.m., Columbia Line 1278 failed near Milford, PA, during an uprating procedure to increase the pressure in the line from a reduced 800 psig operating pressure back to the original 1000 psig MAOP of the pipeline. Emergency Response Time Event 950 psig. Began leak patrols of pipeline segment, with a total of four patrols at 800, 850, 900, and 11:45 AM, 11/04/08 4:10 PM, 11/04/08 Attained 950 psig increment with pressure held overnight. 10:30 AM, 11/05/08 Began leak patrol of pipeline segment 1:58 PM Telemetry Record Rupture 2:14 PM Gas Controller notices pressure drop on SCADA 2:15 PM Smith dispatched to Weber Road facility 2:19 PM Weitzel contacted by Gas Control 2:23 PM Palmer returns call to Gas Control and reports personnel are responding 2:40 PM Telemetry indicates closure of Milford mainline valve 3:37 PM Compliance & Technical Training; incident reported to NRC (Report No. 889241). 3:48 PM Telemetry indicates closure of Weber Road mainline valve (launcher) 4:06 PM Palmer reports to Gas Control the site is secure and reports rupture location 5:45 PM Personnel leave the rupture site for the night 6:00 PM Gas Control conducts conference call to review events and status 5:45 AM, 11/06/08 Burnley arrives at site to preserve evidence and begin preliminary investigative process pending arrival of Federal and third party investigators. Note: Investigative process and repair activities continued 12 hours per day through to 11/24/08. Summary of initial start-up plan and return-to-service, including preliminary safety measures Columbia installed 510 feet of new 14-inch, coated, steel pipeline in the wetland area to replace the pipe that failed. On December 6, 2008, service was restored in the pipeline. 122980 Summary DM CGT 2616 Easton 2901 Line 1278 I03 11052008.docx Page 3 of 4#

Page 4Failure Investigation Report – Columbia Gas Transmission Rupture – Activity ID 122980 Investigation Findings & Contributing Factors The failed section of pipe separated into four pieces. These pieces along with several other segment of the pipeline were visually examined and analyzed by Kiefner and Associates, Inc. The lab tests results indicated that the failure was caused by near-neutral-pH stress corrosion cracking (SCC). This has been noted in the company reported apparent cause in Part G of Appendix 3. Appendices 1 Photo Documentation 2 NRC Report 3 CGT Incident Report 4 CGT Pressure Test Chart 5 CGT Rupture Map 6 Line 1278 and Line K 122980 Summary DM CGT 2616 Easton 2901 Line 1278 I03 11052008.docx Page 4 of 4#

Page 5Appendix 1 - Photos - 122980 Pipeline Failure Investigation Report Figure 1: Severed 14.9 foot section of pipeline Figure 2: Severed 37.1 foot section of pipeline Page 1 of 5#

Page 6Appendix 1 - Photos - 122980 Pipeline Failure Investigation Report Figure 3: Severed 9 foot section of pipeline Figure 4: Severed 4.7 foot section of pipeline, piece 4 Page 2 of 5#

Page 7Appendix 1 - Photos - 122980 Pipeline Failure Investigation Report Figure 5: End of severed 37.1 foot section of pipeline Figure 6: End of 21.7 foot section of pipe in swamp Page 3 of 5#

Page 8Appendix 1 - Photos - 122980 Pipeline Failure Investigation Report Figure 7: Bent 21.7 foot section of pipe in swamp Figure 8: Ruptured pipe in swamp Page 4 of 5#

Page 9Appendix 1 - Photos - 122980 Pipeline Failure Investigation Report Figure 9: Piece 4 exhibiting corrosion Page 5 of 5#

Page 10Page 1 of 2 NATIONAL RESPONSE CENTER 1-800-424-8802 *** For Public Use *** Information released to a third party shall comply with any applicable federal and/or state Freedom of Information and Privacy Laws Incident Report # 889241 INCIDENT DESCRIPTION *Report taken at 15:46 on 05-NOV-08 Incident Type: PIPELINE Incident Cause: UNKNOWN Affected Area: The incident occurred on 05-NOV-08 at 14:10 local time. Affected Medium: AIR ATMOSPHERE ____________________________________________________________________________ SUSPECTED RESPONSIBLE PARTY Organization: COLUMBIA GAS TRANSMISSION CHARLESTON, WV 25314 Official Material Name: NATURAL GAS Type of Organization: PRIVATE ENTERPRISE ____________________________________________________________________________ INCIDENT LOCATION RT. 6 AND INTERSTATE I-84 County: PIKE State: PA Section: N/A Township: N/A Range: N/A ____________________________________________________________________________ RELEASED MATERIAL(S) CHRIS Code: ONG Also Known As: Qty Released: 0 UNKNOWN AMOUNT ____________________________________________________________________________ DESCRIPTION OF INCIDENT THE CALLER STATED THAT A PIPELINE (#1278) WAS IN THE PROCESS RAISING THE PSI AND A LEAK WAS DETECTED CAUSING A FIRE TO SHOOT UP FROM THE PIPELINE. NO INJURIES OR FATALITIES HAVE BEEN REPORTED. THE FIRE HAS BEEN EXTINGUISHED AND THE VALVES WERE SHUT OFF SECURING THE RELEASE. NO CUSTOMER SERVICE WAS LOST IN THE INCIDENT. THE CAUSE OF THE LEAK IS STILL UNDER INVESTIGATION. ____________________________________________________________________________ INCIDENT DETAILS Pipeline Type: TRANSMISSION DOT Regulated: YES Pipeline Above/Below Ground: ABOVE Exposed or Under Water: NO Pipeline Covered: UNKNOWN ____________________________________________________________________________ DAMAGES Fire Involved: YES Fire Extinguished: YES INJURIES: NO Hospitalized: Empl/Crew: Passenger: FATALITIES: NO Empl/Crew: Passenger: Occupant: EVACUATIONS: NO Who Evacuated: Radius/Area: Damages: NO Length of Direction of Closure Type Description of Closure Closure Closure Air: N Road: N Major Artery: N Waterway: N Track: N http://www.nrc.uscg.mil/reports/rwservlet?standard web+inc _ _ seq=889241 3/15/2011#

Page 11Page 2 of 2 Passengers Transferred: NO Environmental Impact: NO Media Interest: NONE Community Impact due to Material: ____________________________________________________________________________ REMEDIAL ACTIONS RELEASE SECURED, FIRE EXTINGUISHED WHEN VALVE WAS CLOSED Release Secured: YES Release Rate: Estimated Release Duration: ____________________________________________________________________________ WEATHER Weather: PARTLY CLOUDY, ºF Wind speed: 5 MPH ____________________________________________________________________________ ADDITIONAL AGENCIES NOTIFIED Federal: NONE State/Local: FIRE, POLICE State/Local On Scene: FIRE, POLICE State Agency Number: NONE ____________________________________________________________________________ NOTIFICATIONS BY NRC ATLANTIC STRIKE TEAM (MAIN OFFICE) 05-NOV-08 15:54 USCG ICC (ICC ONI) 05-NOV-08 15:54 DOT CRISIS MANAGEMENT CENTER (MAIN OFFICE) 05-NOV-08 15:54 U.S. EPA III (MAIN OFFICE) 05-NOV-08 15:56 FLD INTEL SUPPORT TEAM PHILADELPHIA (MAIN OFFICE) 05-NOV-08 15:54 USCG COMMAND CENTER (MAIN OFFICE) 05-NOV-08 15:55 NATIONAL INFRASTRUCTURE COORD CTR (MAIN OFFICE) 05-NOV-08 15:54 NJ STATE POLICE (MARINE SERVICES BUREAU) 05-NOV-08 15:54 NOAA RPTS FOR PA (MAIN OFFICE) 05-NOV-08 15:54 NATIONAL RESPONSE CENTER HQ (MAIN OFFICE) 05-NOV-08 15:55 BUREAU TOXIC SUBSTANCE R. WILBURN (MAIN OFFICE) 05-NOV-08 15:54 NJ DEP POC: DUTY OFFICER (MAIN OFFICE) 05-NOV-08 15:54 PA EMERG MGMT AGCY (MAIN OFFICE) 05-NOV-08 15:54 ____________________________________________________________________________ ADDITIONAL INFORMATION THE CALLER HAD NO ADDITIONAL INFORMATION. ___________________________________________________________________________ *** END INCIDENT REPORT # 889241 *** http://www.nrc.uscg.mil/reports/rwservlet?standard web+inc _ _ seq=889241 3/15/2011#

Page 12122980 Appendix 3 Incident Report NOTICE: This report is required by 49 CFR Part 191. Failure to report can result in a civil penalty not to exceed $25,000 for each violation Form Approved for each day that such violation persists except that the maximum civil penalty shall not exceed $500,000 as provided in 49 USC 1678. OMB No. 2137-0522 U.S. Department of Transportation Research and Special Programs Administration INCIDENT REPORT - GAS TRANSMISSION AND GATHERING SYSTEMS Report Date No. (DOT Use Only) INSTRUCTIONS Important: Please read the separate instructions for completing this form before you begin. They clarify the information requested and provide specific examples. If you do not have a copy of the instructions, you can obtain one from the Office Of Pipeline Safety Web Page at http://ops.dot.gov . PART A – GENERAL REPORT INFORMATION Nearest street or road City and County or Parrish a. b. c. State and Zip Code d. Mile Post/Valve Station e. Survey Station No. f. Latitude: Longitude: (if not available, see instructions for how to provide specific location) g. Class location description Onshore: Class 1 Class 2 Class 3 Class 4 Offshore: Class 1 (complete rest of this item) Area ___________________ Block # ___________ State / / or Outer Continental Shelf h. Incident on Federal Land other than Outer Continental Shelf Yes No i. Is pipeline Interstate Yes No 4. Type of leak or rupture Leak: Pinhole Connection Failure (complete sec. F5) Puncture, diameter (inches) Rupture: Circumferential – Separation Longitudinal – Tear/Crack, length (inches) Propagation Length, total, both sides (feet) N/A Other: Operator Name and Address Original Report Supplemental Report Final Report a. Operator's 5-digit Identification Number (when known) / / b. If Operator does not own the pipeline, enter Owner’s 5-digit Identification Number (when known) / / c. Name of Operator ______________________________ _______________________________________________________ d. Operator street address ________________________________________________________________________________________ e. Operator address _______________________ City, County or Parrish, State and Zip Code 2. Time and date of the incident / / / / / / / / hr. month day year 3. Location of incident 5. Consequences (check and complete all that apply) a. Fatality Total number of people: / / Employees: / / General Public: / / Non-employee Contractors: / / b. Injury requiring inpatient hospitalization Total number of people: / / Employees: / / General Public: / / Non-employee Contractors: / / c. Property damage/loss (estimated) Total $ Gas loss $ Operator damage $ Public/private property damage $ d. Release Occurred in a ‘High Consequence Area’ e. Gas ignited – No explosion f. Explosion g. Evacuation (general public only) / / people Reason for Evacuation: Emergency worker or public official ordered, precautionary Threat to the public Company policy 6. Elapsed time until area was made safe: / / hr. / / min. 7. Telephone Report / / / / / / / / NRC Report Number month day year 8. a. Estimated pressure at point and time of incident: PSIG b. Max. allowable operating pressure (MAOP): PSIG c. MAOP established by 49 CFR section: 192.619 (a)(1) 192. 619 (a)(2) 192. 619 (a)(3) 192.619 (a)(4) 192. 619 (c) d. Did an overpressurization occur relating to the incident? Yes No PART B – PREPARER AND AUTHORIZED SIGNATURE Area Code and Telephone Number (type or print) Preparer's Name and Title Preparer's E-mail Address Area Code and Facsimile Number Date Area Code and Telephone Number Authorized Signature (type or print) Name and Title Form RSPA F 7100.2 ( 01-2002 ) OPS Data Facsimile Page 1 of 3 1 of 3#

Page 13122980 Appendix 3 Incident Report PART C - ORIGIN OF THE INCIDENT 1. Incident occurred on Transmission System Gathering System Transmission Line of Distribution System 2. Failure occurred on Body of pipe Pipe Seam Joint Component Other: 3. Material involved (pipe, fitting, or other component) Steel Plastic (If plastic, complete all items that apply in a-c) Plastic failure was: a.ductile b.brittle c.joint failure Material other than plastic or steel: _________ 4. Part of system involved in incident Pipeline Regulator/Metering System Compressor Station Other: 5. Year the pipe or component which failed was installed: / / PART D – MATERIAL SPECIFICATION (if applicable) PART E – ENVIRONMENT 1. Nominal pipe size (NPS) / / in. 2. Wall thickness / / in. 3. Specification SMYS / / 4. Seam type 5. Valve type 6. Pipe or valve manufactured by in year / / 1. Area of incident In open ditch Under pavement Above ground Under ground Under water Inside/under building Other: 2. Depth of cover: inches PART F – APPARENT CAUSE Important: There are 25 numbered causes in this section. Check the box to the left of the primary cause of the incident. Check one circle in each of the supplemental items to the right of or below the cause you indicate. See the instructions for this form for guidance. F1 – CORROSION If either F1 (1) External Corrosion, or F1 (2) Internal Corrosion is checked, complete all subparts a – e. a. Pipe Coating b. Visual Examination c. Cause of Corrosion Bare Galvanic Stray Current 1. External Corrosion Localized Pitting Coated General Corrosion Improper Cathodic Protection Other: ____________________ Microbiological Stress Corrosion Cracking Other: ____________________ 2. Internal Corrosion d. Was corroded part of pipeline considered to be under cathodic protection prior to discovering incident? No Yes, Year Protection Started: / / e. Was pipe previously damaged in the area of corrosion? No Yes, How long prior to incident: / / years / / months F2 – NATURAL FORCES 3. Earth Movement => Earthquake Subsidence Landslide Other: 4. Lightning 5. Heavy Rains/Floods => Washouts Flotation Mudslide Scouring Other: 6. Temperature => Thermal stress Frost heave Frozen components Other: 7. High Winds F3 - EXCAVATION 8. Operator Excavation Damage (including their contractors) / Not Third Party 9. Third Party Excavation Damage (complete a-d) a. Excavator group General Public Government Excavator other than Operator/subcontractor b. Type: Road Work Pipeline Water Electric Sewer Phone/Cable Landowner Railroad Other: c. Did operator get prior notification of excavation activity? No Yes: Date received: / / mo. / / day / / yr. Notification received from: One Call System Excavator Contractor Landowner d. Was pipeline marked? No Yes (If Yes, check applicable items i – iv) i. Temporary markings: Flags Stakes Paint ii. Permanent markings: Yes No iii. Marks were (check one) Accurate Not Accurate iv. Were marks made within required time? Yes No F4 – OTHER OUTSIDE FORCE DAMAGE 10. Fire/Explosion as primary cause of failure => Fire/Explosion cause: Man made Natural 11. Car, truck or other vehicle not relating to excavation activity damaging pipe 12. Rupture of Previously Damaged Pipe 13. Vandalism 2 of 3 Form RSPA F 7100.2 ( 01-2002 ) Page 2 of 3#

Page 14122980 Appendix 3 Incident Report F5 – MATERIAL AND WELDS Material 14. Body of Pipe => Dent Gouge Wrinkle Bend Arc Burn Other: 15. Component => Valve Fitting Vessel Extruded Outlet Other: 16. Joint => Gasket O-Ring Threads Other: Weld 17. Butt => Pipe Fabrication Other: 18. Fillet => Branch Hot Tap Fitting Repair Sleeve Other: 19. Pipe Seam => LF ERW DSAW Seamless Flash Weld HF ERW SAW Spiral Other: Complete a-g if you indicate any cause in part F5. a. Type of failure: Construction Defect => Poor Workmanship Procedure not followed Poor Construction Procedures Material Defect b. Was failure due to pipe damage sustained in transportation to the construction or fabrication site? Yes No c. Was part which leaked pressure tested before incident occurred? Yes, complete d-g No d. Date of test: / / mo. / / day / / yr. e. Test medium: Water Natural Gas Inert Gas Other: f. Time held at test pressure: / / hr. g. Estimated test pressure at point of incident: PSIG F6 – EQUIPMENT AND OPERATIONS 20. Malfunction of Control/Relief Equipment => Valve Instrumentation Pressure Regulator Other: 21. Threads Stripped, Broken Pipe Coupling => Nipples Valve Threads Mechanical Couplings Other: 22. Ruptured or Leaking Seal/Pump Packing 23. Incorrect Operation a. Type: Inadequate Procedures Inadequate Safety Practices Failure to Follow Procedures Other: b. Number of employees involved who failed post-incident drug test: / / Alcohol test: / / c. Were most senior employee(s) involved qualified? Yes No d. Hours on duty: / / F7 – OTHER 24. Miscellaneous, describe: 25. Unknown Investigation Complete Still Under Investigation (submit a supplemental report when investigation is complete) PART G – NARRATIVE DESCRIPTION OF FACTORS CONTRIBUTING TO THE EVENT (Attach additional sheets as necessary) Form RSPA F 7100.2 ( 01-2002 ) OPS Data Facsimile Page 3 of 3 3 of 3#

Page 15122980 Appendix 4 Columbia Pipeline Pressure test Graph 1 of 1#

Page 16122980 Appendix 5 - Columbia Gas Line 1278 Rupture map 1 of 1#

Page 17122980 Appendix 6 - Line 1278 and K Columbia Gas Transmission Line 1278 and Line K 02/09/2011 02/09/2011 MP 7339+85 ‐ 11/05/2008 Failure Location in Pike Co. MP 7338 17 7343 27 Sparrowbush MP 7338+17 – 7343+27 Section C CS replaced 510 ft with 14” pipe Section A Section B Hellertown CS Easton CS Milford CS Line K Line 1278 Quakertown Bangor Millrift g g Stroudsburg Bushkill Weber Road PA‐NY State Line Not Included in CAO Replaced approximately 11 miles 14” pipe with 14” coated pipe Replaced approximately 42 miles of 14” pipe with 20” coated pipe “CGT Anticipates construction to replace this section starting in May 2011 and ending in September 2011. NGT&S commits to maintaining the operating pressure at a restricted level of 800 psig, as established by the CAO, from Weber Road in PA to the CAO Section A Quakertown M&R Station to the Hellertown M&R Station Sparrowbush Compressor Station in NY. This section contains the CAO Section B Easton Compressor Station to the Delaware River Crossing at the PA‐NY State Line remaining 14” bare pipe along Lines CAO Section C All Uncoated Segments from Quakertown to Hellertown and from Easton to the PA‐NY State Line CAO Section C All Uncoated Segments from Quakertown to Hellertown and from Easton to the PA NY State Line 1278 and Line K. NGT&S commits to 1278 d Li K NGT&S i replace the remaining bare pipe in PA; approximately 12 miles.” According to Columbia letter dated November 30, 2010. CPF# 1‐2002‐1004H 1 of 1#