Failure Report- National Fuel Gas 12/21/09

Page 1Official PDFFailure Investigation Report – National Fuel Gas Rupture – Activity ID 128512 Principal Investigator Patrick Raichel - NYDPS Regional Director Byron Coy Date of Report 03/02/2011 Subject Failure Investigation Report – Line K rupture near Knoll Road Summary: On December 21, 2009, at approximately 11:30 am National Fuel Gas (NFG) Dispatching received a call from the local police department reporting a pipeline “explosion” in the vicinity of New Oregon Road, Eden, NY. A review of the SCADA system and additional phone calls from the public indicated that NFG’s Line K was experiencing a severe pressure loss. NFG crews were dispatched to the vicinity and valves were manned. After operating the valves, the pipeline was secured at 12:32 pm. There was no ignition or explosion of the escaping natural gas. Further investigation determined that Line K was ruptured at a point some 641 feet south of Knoll Road, north of New Oregon Road in Eden, NY. The rupture was evident as the pipeline segment-self excavated due to the operating pressure and the extent of the rupture. On December 22, 2009, the ruptured section was removed and retained for metallurgical analysis. After removal, the line was repaired by replacing a four foot section of 20” pipe. New York Department of Public Service (NYDPS) Staff was present during all field activities starting with the field investigations on 12/21/2009. An analysis of the ruptured pipe was conducted by the Battelle Memorial Institute of Columbus, Ohio, which determined the following: “A guillotine rupture occurred on Line K, a 20-inch diameter pipeline with a 0.375-inch thick wall made of early vintage Grade B steel. The operating pressure at the time of failure was reported at 180 psig. Operator, Location, & Consequences Date & Time of Failure: 12/21/2009 Commodity Released: Natural Gas City/County & State: Knoll Rd., Eden, NY OpID & Operator Name 13063 National Fuel Gas Unit # & Unit Name 2021 Northern District SMART Activity #: 128512 Milepost / Location Lat: N42.61020 Long: W078.81948 Type of Failure: Rupture Fatalities: 0 Injuries 0 Description of area impacted Rural Property damage $84,800 National Fuel Gas GT NY 508 2009-12-21.docx Page 1 of 3#

Page 2Failure Investigation Report – National Fuel Gas Rupture – Activity ID 128512 System Details Line K originates at the NY/PA state border, carrying gas through Cattaraugus and Erie Counties. It terminates at regulator station WSE85, located along Seneca St., West Seneca, NY. It consists of 42 miles of 20" pipe and 18 miles of 16" pipe that was installed in 1910. Events Leading up to the Failure 11:30 am, 12/21 11:40 am, 12/21 12:12 pm, 12/21 12:28 pm, 12/21 12:32 pm, 12/21 3:00 pm, 12/22 3:30 pm, 12/23 1:45 pm, 12/29 NFG Dispatcher begins to receive phone reports of natural gas explosion along New Oregon Rd., Boston, NY NFG confirms gas loss on line K through SCADA reading and begins dispatching personnel Valves BNE-193 and BNE-195 are closed NYS DPS Staff is notified by NFG Valve NCE-5 is closed, flow of gas is secured, effected pipeline segment is isolated Ruptured segment of pipeline is cut out and secured for metallurgical testing Pipeline is repaired Pipeline is re-pressurized, tested and restored to service at reduced operating pressure Emergency Response In response to the rupture, NFG personnel secured three valves (BNE-193, BNE-195 and NCE-5). Six people were evacuated. NY DPS dispatched personnel and arrived on site at 2:30 pm on 12/21/2009. Summary of initial start-up plan and return-to-service, including preliminary safety measures After repair was made to pipeline segment and purged, NFG put the line back into service. The line was re- pressurized in three stages, 175 psig, 200 psig and finally 220 psig. Flame ionization surveys were conducted after each increment with negative results. After the third leak survey, the pressure was reduced to 175 psig. On 12/29/2009, a pressure reduction was imposed by NFG Engineering Dept. on all of line K, from 220 psig MAOP to 185 psig until the section of line was replaced. Investigation Findings & Contributing Factors “A guillotine rupture occurred on Line K, a 20-inch diameter pipeline with a 0.375-inch thick wall made of early vintage Grade B steel. The operating pressure at the time of failure was reported at 180 psig • Field measurements made after the line blew-down indicate that axial strains in excess of the yield strain developed due to local bending and line tension, • The origin for the failure was identified as a pair of pits coincidentally located within the crown of the pipe in the vicinity of the maximum axial stresses, • The unusual local axial loadings acting on the pair of coincidentally located pits was sufficient to cause through-wall instability, which given the brittle nature of the steel led to guillotine failure, which was facilitated by the winter temperatures working in • Conjunction with the inherently high Ductile to Brittle Transition Temperature (DBTT) leading to reduced fracture toughness, • Stress concentration at the bottom of the pits could, when acting under the effects of just the local bending strain would be (sic) sufficient to cause crack nucleation at the root of the pitting, which served National Fuel Gas GT NY 508 2009-12-21.docx Page 2 of 3#

Page 3Failure Investigation Report – National Fuel Gas Rupture – Activity ID 128512 as the origin for subsequent crack growth. • The failure was due to a unique combination of factors that involved locally high bending and axial strains unique to the vicinity of over bend across the ridge where the failure occurred, free of other contributory or causative factors.” Topography played a role in the stress loading of the pipeline at the break site. The break occurred at the top of a ravine, with the ridgeline running approximately perpendicular to the pipeline. Appendices 1 NRC 926772 2 Incident report 20090141 -- 8341 3 Incident Location National Fuel Gas GT NY 508 2009-12-21.docx Page 3 of 3#

Page 4TeleDetail HMIS->INCiDENTs->TELEPhONiCs (Version 3.4.05 PROD ) Rules of Behavior Home Logout Menu [Return to Search] 1..1 of 1 Rescinded Comments (max 250 characters) NRC Number: 926772 Call Date: 12/21/2009Call Time: 13:17:12 Caller Information First Name: Last Name: Company Name: Address: City: State: Country: Zip: Phone 1: Phone 2: Organization Type: Is caller the spiller? Yes No No Response Confidential: Yes No No Response Discharger Information First Name: Last Name: Company Name: Address: City: State: Country: Zip: Phone 1: Phone 2: Organization Type: Spill Information State: County: Nearest City: Zip Code: Location Spill Date: (mm/dd/yyyy) Spill Time: (24hh:mm:ss) DTG Type: DISCOVERED Incident Type PIPELINE Reported Incident Type Description https://phmhqnwas003/...illed=%3d&reportingCompany=&operreportingCompany=%3d&responsibleCompany=&OperresponsibleCompany=%3d&startno=1[2/17/2011 9:48:10 AM]#

Page 5TeleDetail Materials Involved Material / Chris Name Chris Code Total Qty. Water Qty. NATURAL GAS ONG 0 UNKNOWN AMOUNT Medium Type: AIR Additional Medium Information: Injuries: Fatalites: Evacuations: Yes No Unknown No. of Evacuations: Damages: Yes No Unknown Damage Amount: Federal Agency Notified: Yes No Unknown State Agency Notified: Yes No Unknown Other Agency Notified: Yes No Unknown Remedial Actions Additional Info Latitude Degrees: Minutes: Seconds: Quadrant: Longitude Degrees: Minutes: Seconds: Quadrant: Distance from City: Direction: Section: Township: Range: Milepost: https://phmhqnwas003/...illed=%3d&reportingCompany=&operreportingCompany=%3d&responsibleCompany=&OperresponsibleCompany=%3d&startno=1[2/17/2011 9:48:10 AM]#

Page 6NOTICE: 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#

Page 7PART 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 Form RSPA F 7100.2 ( 01-2002 ) Page 2 of 3#

Page 8F5 – 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#

Page 9446 mn Of N42.61020, W078.81948 + × Incident Location - Line K Knoll Rd New Oregon Rd on Brook Hampton Brook#

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