Pipeline Failure investigation Report Atmos Energy Corp., Mid-Tex Pipeline System: Irving Operator: Division Location: 2602 Syracuse Date of Occurrence: 5/3l2009 Medium Released: Natural Gas Quantity: Unknown PHMSA Arrival Time Date: NIA Total Damages 175,000 Investigation Responsibility: IE State PHMSA NTSB Other Company Reported Apparent Cause: Corrosion El Excavation El Natural Forces El Incorrect Operation Other Outside Force Damage I: Material and/or Welds El Equipment and Operations Other Unknown Rupture Yes No Leak Yes No Fire a Yes No Explosion Yes No Evacuation Yes No Number of Persons Area Narrative Summary Short summary of the Incident/Accident which will give interested persons sufficient information to make them aware of the basic scenario and facts. On Sunday, May 3, 2009 at approximately 2:00 a house explosion occurred at 2602 Syracuse Drive in Irving, Texas. There was one injury as a result of the incident. Subsequent investigation revealed that there was a leak on a compression coupling, connecting the coated steel service line at the tap to 2601 Syracuse Drive. The main supplying 2601~ and 2602 Syracuse Drive is a four-inch coated steel line and is located in front of the 2602 Syracuse Drive residence, in the parkway between the sidewalk and the street curb. The natural gas distribution system is owned and operated by Atmos Energy. RegionIStute _Region 5 i Texas Reviewed by: Principal Investigator: _Terry Sullivan Title: Date: June 26,2009 Date: - 1 Form 11 Pipeline Failure Investigation Report (Revised Pipeline Failure Investigation Report Failure Location Response Location (City, Township, Ranger (Acquire Map) Irving, Dallas County Address or MP. on Pipeline: Type of Area (Rural, City): 2602 Syracuse City Date: 53/2009 Time of Failure: Unknown Time Detected: 2:00 p.t'n. Time Located: 2:20 pm How Located: House Explosion Bar testing and testing sewer vents NRC Report {Attach Report) Time Reported to NRC: Reported by: 904497 Monday, May 4, 2009 at 2:55 am. Atmos - Ken Parks Type of Pipeline: Gas Distribution Gas Transmission Hazardous Liquid LNG [Jr Interstate Gas Interstate Liquid LNG Facility '3 Municipal Intrastate Gas Intrastate Liquid a Public Utility Jurisdictional Gas Gathering onshore Liquid Master Meter '3 Offshore 035 Jurisdictional Liquid Gathering Offshore Gas - High as co, Pipeline Con?guration (Regulator Station. Pump Station, Pipeline, etc}: Four-inch coated steel main with one-inch steel service line connected with a compression coupling. Operator/Owner Information Owner: Atmos Energy Corp., Mid-Tex Division Operator: Atmos Energy Corp., Mid-Tex Division Address: Address: P.O. Box 223705 P.0. Box 223705 Dallas, Texas Dallas, Texas Company Of?cial: M5. Patti Richards Company Of?cial: Ms. Patti Richards Phone No_: 214-206-2807 Fax No.: 214-206-2126 Phone No. 214-206-2807 Fax No. 214-206-2126 Drue and Alcohol Testing Program Contacts Drug Program Contact Phone: Flalyn Fletcher 5430 LBJ Freeway, Dallas, Texas, Lincoln Three - 5"1 Floor, 972-855-4084 Alcohol Program Contact Phone: Flalyn Fletcher 5430 LBJ Freeway, Dallas, Texas, Lincoln Three - 5"1 Floor, 972-655-4064 Damages Product/Gas Loss or Spillm Unknown Estimated Property Damage 3 175,000 Amount Recovered NIA Associated Damages?? 1 Photo documentation 2 Initial volume lost or spilled 3 Including cleanup cost 2 - Form 11 Pipeline Failure Investigation Report (Revised 03i02t'07) Pipeline Failure Investigation Report Damages Estimated Amount NIA Description of Property Damage: The house at 2602 Syracuse Drive is a one-story brick and wood house on a slab foundation. The house is a total loss. 2532 Syracuse Driv, was also damaged the cost of repair is unknown. It is located on east side of 2602 Syracuse Drive. Customers out of Service; Yes No Number: 1 Suppliers out of Service: Yes No Number: Fatalities and Injuries Fatalities: Yes No Company: Contractor: Public: Injuries - Hospitalization: Yes No Company: Contractor: Public: _1 Injuries - Non-Hospitalization: Yes No Company: Contractor: Public: Total Injuries (including Non-Hospitalization): Company: Contractor: Public: 1 w! Yrs. Name Job Function comP- Exp- Bradley G. Luttrell Public - Home Owner NM NM Drug/Alcohol Testing Were all employees that could have contributed to the incident, post-accident tested within the 2 hour time frame for alcohol or the 32 hour time frame for all other drugs? El Yes El No Results Job Function Test Date Time Location Type of Drug os CIDEIDEI Form 11 Pipeline Failure Investigation Report (Revised 03l02l07) Pipeline Failure Investigation Report System Description Describe the Operator's System: Atmos records were reviewed to obtain information regarding the operation of the pipeline system. The natural gas distribution system is owned and operated by Atmos Energy Corporation. The Irving distribution system has a maximum allowable operating pressure of 50 p.s.i.g. At the time of the incident on Sunday, May 3, 2009 the actual operating pressure was 21.0 p.s.i.g. at the Measuring Station designated as MS 4611 Irving North - Finley Rd. The main supplying 2602 Syracuse Drive is a four-inch coated steel line and is located in front of the residence. in the parkway between the sidewalk and the street curb. The original Project number the main was installed under sometime in 1960, is however the records could not be located to obtain the exact date the main was placed in service. The service line supplying 2602 Syracuse Drive was originally installed by Lone Star Gas (now Atmos) under Service Line No. 16854 dated 10/4/63. The scope of work was to instail three feet of one-inch coated pipe. The service line was replaced under (Ref. EFI No. 6790-79) on June 14, 1979. The scope of work called for the replacement of the one-inch coated steel service line with ten feet of PE 2306 polyethylene pipe but the actual footage on-site differs. The approximate length from the tap to the customer service meter is forty-three feet. The service line supplying 2601 Syracuse (ER No. 6-60} was originally installed by Lone Star Gas (now Atmos) under Service Line No. 13403 dated 0/5i60. The scope of work was to install thirty-six feet of one-inch coated steel pipe. During excavation of the service line, it was discovered that a transition fitting had been installed extending the service line with PE 2306 polyethyiene pipe. Atmos could not locate records of the date the PE 2306 polyethylene pipe extension occurred but the date on the PE 2306 polyethylene pipe shows the pipe was manufactured in June of 1980. Pipe Failure Description Length of Failure (inches. feet. miles): NIA Position (Top, Bottom, include position on pipe, 6 O'clock): Description of Failure (Corrosion Gouge, Seam Split): Compression Coupling Gasket Laboratory Analysis: Yes No Performed by: Unified investigations 8: Sciences, Inc. Preservation of Failed Section or Component: EYes No Atmos Energy welded metal strapping from the one-inch steel service line that connected to 2601 If Yes - Method: Syracuse to the four-inch coated steel main where the coupling was installed. Unified sealed and secured the section of piping. In Custody of: Unified Investigations 8: Sciences, Inc. Develop a sketch of the area including distances from roads, houses, stress inducing factors. pipe con?gurations, etc. Bar Hole -4- Form 11 Pipetine Failure Investigation Repon (Revised 03i02107) Pipeline Failure Investigation Report Pipe Failure Description Test Survey Plot should be outlined with concentrations at test points. Direction of Flow. Component Failure Descriptidn . El Component Failed: Compression Coupling Gasket Manufacturer: Normac Model; Unknown Pressure Rating: Unknown Size; Onainch coup?ng Other (Breakout Tank, Underground Storage): .. . . .. Material: Wall Thickness/SDR: Diameter Installation Date: SMYS: Manufacturer: Longitudinal Seam: Type ofCoating: Pipe Speci?cations (API 5L, ASTM A53, etc.): I Joining El Type: Welded Tap and Mechanical Fitting Procedure: NIA NDT Method: NIA Inspected: Yes No Pressure Time of Failure Failure Site Pressure Failure Site: 17 PSI Elevation Failure Site: 545.03 Ft. Pressure Readings Various Locations: Direction from Failure Site Pressure (psig) Elevation (ft msl) Upstream MS 4611 Irving North Finley Rd. 21.0 NIA One block West of Story Road Upstream Station Data . . IZI Type of Product: Natural Gas API Gravity: Speci?c Gravity: Flow Rate: - 5 - Form 11 Pipeline Failure Investigation Report (Ftevised esteem?) Pipeline Failure investigation Report Upstream Pump Station Data I I Pressure Time of Failure Distance to Failure Site: High Pressure Set Point: Low Pressure Set Point: . Upstream Compressor Station Data . Speci?c Gravity: Flow Rate: Pressure Time of Failure Distance to Failure Site: High Pressure Set Point: Low Pressure Set Point: Operating Pressure I - Max. Allowable Operating Pressure: 50 p.s.i.g. Dm?rmin??on 0f MAOP: Pressure Actual Operating Pressure: 21 .0 p.s.i.g. at MS 461 1 Irving North - Finley Ftd. Method of Over Pressure Protection: Monitor Relieraive Set Point: NIA Capacity Adequate? Yes No Integrity Test After Failure Pressure Test Conducted in place? (Conducted on Failed Components or Associated Piping): Yes No ll'NO, Tested after removal? Yes CI No Method: Pressure Test and Liquid Soap Test both in place and at Unified Investigations lab. Describe any failures during the test. At the site of the incident, liquid soap was applied to the compression coupling connected to the service line at 2601 Syracuse Drive, the compression coupling demonstrated that it was leaking with the presence of large, medium and small bubbles. The leak was also very audible and blowing. At Unified investigations lab, during the pressure test, the coupling from the service line at 2601 Syracuse Drive failed the pressure test with compressed air, later liquid soap was applied, and the coupling demonstrated the severity of the leak with large, medium and small bubbles. Flow rate test was also performed. soil/water Conditions Failure Site . Condition oiand Type of Sci! around Failure Site [Colon Wet. Dry, Frost Depth): Very wet clay soil for twelve to fifteen inches, then moist clay and sand mix. The area around the compression was very dry and discolored. Type of Backiil] (Size and Description): Fresh sand and clay soil. _A_ll, spoil soils were hauled-off. Type of Water (Salt. Brackish): wan?. Analysis Yes No External I or Com orient Exaritination El External Corrosion? I: Yes Nu "3 Coating Condition (Disbonded, Non-existent): l? Good 4 Obtain event logs and pressure recording charts 5 Attach copy of water analysis report Form 11 Pipeline Failure Investigation Report (Revised OSIOZIOY) Pipeline Failure Investigation Report External Pipe or Gomponent Examination El Description of Corrosion: Description of Failure Surface (Gouges. Arc Burns, Wrinkle Bends, Cracks, Stress Cracks, Chevrons, Fracture Mode, Point of Origin); NIA Above Ground: Yes No Buried: Yes No Stress Inducing Factors: NIA Depth of Cover: 42? Depth - Documented Cathodic Protection . PIS (Surface): -'l.17v. Before anode installed PIS (lnterface}: Unknown 8: -1.21v. After anode installed Soil Resistivity: Unknown 131-]: Unknown Date of Installation: Unknown Method of Protection: Anode Did the Operator have knowledge of Corrosion before the Incident? Yes No How Discovered? (Close Interval Survey, Instrumented Pig, Annual Survey. Recti?er Readings. ECDA. etc): CP Zone 81A, lrving Book 2, the zone has two test points and protects approximately 3,759 feet of coated steel pipe. The last two annual survey readings were 2008 Test Point 1, - 0.96v, Test point 2. - 0.85v and 2007 Test Point 1, - 0.96, Test Point 2, - 0.97v. Atmos could not locate readings for Zone 81A previous to the year 2003. Internal Pipeor Component . . Internal Corrosion: Yes No Injected Inhibitors: Yes No Type Of Tesung: El Yes No Results (Coupon Test. Corrosion Resistance Probe): Description ofFailure Surface (MIC, Fitting, Wall Thinning. Chevrons, Fracture Mode, Point of Origin}: Cleaning Pig Program: El Yes El No Gas and/or Liquid Analysis: Yes El No Results of Gas and/or Liquid Analysis Internal Inspection Survey: Yes No Did the Operator have knowledge of Corrosion before the Incident? El Yes No 6 Attach copy of gas and/or liquid analysis report 7 Attach copy of internal inspection survey report Form 11 Pipeline Failure Investigation Report (Revised 0310207} Pipeline Failure Investigation Report I Internal Pipe or Component Examination I How Discovered? Pig, Coupon Testing, ICDA, etc.}: Outside Force Damage I Responsible Party: Telephone No.: Address: Work Being Performed: Equipment Involved: Catled One Call System? Ci Yes No One Call Name: One Call Report Notice Date: Time: Response Date: Time: Details of Response: Was Location Marked According lo Procedures? Yes No Pipeline Marking Type: Location; State Law Damage Prevention Program Followed? El Yes No No State Law Notice Required: El Yes No Response Required; I: Yes No Was Operator Member of State One Cali? El Yes El No Was Operator on Site? Yes No Did a de?ciency in the Public Awareness Program contribute to the accident? El Yes No Is OSHA Noti?cation Required? Yes El No Natural Forces Nat Description (Earthquake. Tornado. Flooding, Erosion): 3 Attach cepy of one-call report Form 11 Pipeline Failure Investigation Fleport (Revised 03i02i07) Pipeline Failure Investigation Report Natural Forces . NIA Failure Isolation Div/A Ijll Squeeze Off/Stopple Location and Method: The main was isolated with Stopple Fittings at the East and West property lines. Valve Closed - Upstream: I.D.: Time: 8:24 pm. on Monday, May 4, 2008 MR: Valve Closed - I-D.: Time: 8:38 pm. on Monday, May 4, 2008 M.P.: Pipeline Shutdown Method: Manual El Automatic El SCADA El Controller ESD Failed Section Bypassed or Isolated: Isolated Performed y: Stopple Fittings Valve Spacing: NIA Odorization - Gas Odorized; Yes Nu Concentration of Odorant (Post Incident at Failure Site): Method of Determination: Yes No LEL: I: Yes No Gas In Air: Yes No ?d?rant Test Time Taken: Yes No 7:30 p.m. Was Odorizer Working Prior tr:- 1he Incident? Type of Odorirer tWick, By-Pass): Injection Yes No Odorant Manufacturer: NJEX 7202 Type of Odorant: Scentinel 0-10 Model: YZ Serial 6701671 Amount Injected: See Below Monitoring Interval (Weekly): Yearly Odorization History (Leaks Complaints. Low Odorant Levels. Monitoring Locations, Distances from Failure Site): Records indicated the last odorant concentration test was performed on Thursday, August 21, 2008 at 9:15 am. with threshold reading of 0.17 percent gas in air concentration and a readily detectable reading of 0.33 percent gas in air concentration. The odorant test was preformed at 3601 North Story Fload (Reference DC- 13793). The distance from 2602 Syracuse Drive to the odorant test point is 1.25 miles. On Sunday, May 3, 2008 at 7:30 Atmos Tech Darwin Hayes performed an odorant test at 2602 Syracuse Drive and witnessed by BBC investigator T. Sullivan. The threshold reading of 0.08 percent gas in air. The 1% Gas in Air rating was Strong. Leak complaints were reviewed for the area and records only indicated one leak investigation order dated Sunday, May 3, 2009. Investigation order dated Sunday, May 3, 2009 indicated the Irving Fire Department -9- Farm 11 Pipeline Failure Investigation Fteport (Ftevised 03102107) Pipeline Failure Investigation Report warrior? E1 M4 reported the incident to Atmos disPatch at 1:58 p.m. 3I31109 LBS. Since Head 0489.0470 Gas Odorized MMCF. 0837.900 Injection Rate 0837.9000 514109 LBS. Since Head 0095.404? Gas Odorized MMCF. 1270.1000 Injection Rate 0.7838 Weather Conditions Temperature: 67 Degrees Wind (Direction Speed): Climate (Snow. Rain): 0F 2.45 Humidity: 100 ?70 Was Incident preceded by :1 rapid weather change? Yes No Weather Conditions Prior to Incident (Cloud Cover, Ceiling Heights, Snow, Rain, Fog): A RECORD FIAINFALL 0F 2.45 INCHES Gas Migration Survey Bar Hole T951 of Area: Yes No Equipment Used: Gas Trak Sensit Gald, 8: Flame Pack( Fl Method of Survey (Foundations. Curbs, Manholes, Driveways, Mains, Services) Bar Test and Flame Ionization survey along the Mains and Services. Atmos retained records of all bar test data post incident. At the time the incident was reported the Technician on-site reported to FIRC Investigator T. Sullivan that he bar tested from the riser to the tap at 2602 Syracuse. The readings at the riser was at five-feet at ten-feet - at fifteen?feet - 0.0% and at the tap connecting to the main 9.0% gas concentration. The reading at the vent stack was . .Enriroementlierisitivity Impact I . le Location (Nearest Rivers, Body of Water. Marshlands, Wildlife Refuge, City Water Supplies that could be or were affected by the medium loss): 9 Plot on site description page -10- Form 11 Pipeline Failure Investigation Report (Revised 03mm?) Pipeline Failure investigation Report Environment Sensitiuily Impact I I I OPA Contingency Plan Available? Yes No Followed-l Yes No Gloss location/High Consequence Area Class Location: 3 HCA Area? Yes No IE NIA Determination: Residential area of Distribution system Determination: Distribution System with 50 p.s.i.g. MAOP Odorization Required? Yes No El Pressure Test History [Exptmi List as Req'd ?"?Assessment . Pressure Duration Deadline Dale Test Date Test Medlum (psig) (hrs) ?it: SMYS Installation NIA Unk Unk Unk Unk NIA Next Next Most Recent Describe any problems experienced during the pressure tests- The ER No. 1843-60 for the four-inch coated steel main could not be located and data is unknown. Internal Line Inspection/Other Assessment History - I NIA (Expand List as Necessan Req?d Assessment Assessment Type of ILI Other Assessment Indicated Anomaly Deadline Date Date Tool Method If yes, describe below Initial Yes No Next Yes El No Next I: Yes No Most Recent Yes No Describe any previously indicated anomalies at the failed pipe. and any subsequent pipe inspections (anomaly digs) and remedial actions. Pre-Failure Conditions and Actions .NIA: Was there a known pre-failure condition requiring the operator to schedule evaluation and remediation? Yes (describe below or on attachment) El No 10 As required of Pipeline Integrity Management regulations in Parts 192 and 195 11 MFL, geometry. crack. etc. 12 ECDA, ICDA, SCCDA, ?other technology." etc. -11- Form 11 Pipeline Failure Investigation Report (Revised 03l02l'07] Pipeline Failure Investigation Report Prev-Failure conditions and Actions If there was such a known pre-failure condition, had the operator established and adhered to a required evaluation and remediation schedule? Describe below or on attachment. Yes No Prior to the failure, had the operator performed the required actions to address the threats that are now known to be related to the cause of this failure? El Yes No El NIA List below or on an attachment such operator-identified threats, and operator actions taken prior to the accident. Describe any previously indicated anomalies at the failed pipe, and any subsequent pipe inspections (anomaly digs) and remedial actions. Maps Records NIA Are Maps and Records Current?? Yes No Comments: The map survey sheet for 2602 Syracuse Drive is AG433990. A special leak survey area was performed post incident bounded by the following map sheets AG433990, AG436992 and AG436990. The four map sheets include the two-block area where the special leak survey was performed post incident. . Leak_survey.Hisrmy . . . M4 Leak Survey History {Trend Analysis, Leak Plots): Map Sheet 433990 Job Date Inspector Pipe Type Units Services Type Number Completed me IKhemmanivanh CS 6974 110 LSA 535170 6110I08 Little Khemmanivanh P2 9488 58 LSA 535170 6110108 Denzil Dean cs 6974 110 LSA 395690 9128105 Denzil Dean P2 7879 58 LSA 395690 9/28l05 The last leak survey was performed on June 2008 by a contractor, Heath Consultants. A special leak survey was performed in the bounded area on Monday, May 4 and Wednesday, May 6, 2009. There were three below ground Grade II leaks found. Pipeline Operation History I I Description (Repair or Leak Reports. Exposed Pipe Reports): Records were reviewed for un-repaired leaks, there were no un-repaired leaks were found for 2601 and 2602 Syracuse. Repaired leaks were also reviewed, there have not been any repaired leaks found for 2601 and 2602 Syracuse. The records reviewed dated back to 1974. Did a Safety Related Condition Exist Prior to Failure? Yes No Reported? Yes No lJnaccountcd For Gas: Irving is part of the metro system lost and unaccounted for gas report. The 12 month reporting period for June ending 2007 shows a 3.34% LUG. Over ShortlLine Balance (24 hr.. Weekly, rend): NIA 13 Obtain copies of maps and records -12- Form 11 Pipeline Failure Investigation Fteport (Revised Pipeline Failure Investigation Report Operator/Contractor Error Name: Job Function: Title: Years of Experience: Training (Type of Training, Background): Was the person ?Operator Quali?ed? as applicable to a precursor abnormal operating condition? I: Yes No Was quali?ed individual suspended from performing covered task Yes No Type of Error (Inadvertent Operation of a Valve): Procedures that are required: Actions that were taken: Pie-Job Meeting (Construction, Maintenance, Blow Down. Purging. Isolation): Prevention of Accidental Ignition (Tag Lock Out, Hot Weld Permit): Procedures conducted for Accidental Ignition: Was a Company Inspector on the Job? Yes No Was an Inspection conducted on this portion of the job? Yes No Additional Actions (Contributing factors may include number of hours at work prior to failure or time of day work being conducted): Training Procedures: Operation Procedures: Controller Activities: Years Hours on Duty Shirl Name Title . . . Experience Prlor to Failure Alarm Parameters: High/Low Pressure Shutdown: Flow Rate: Procedures for Clearing Alarms: Type of Alarm: -13- Form 11 Pipeline Failure investigation Report (Revised DBIOZIUT) Pipeline Failure Investigation Report Operator/Contractor Error Company Response Procedures for Abnormal Operations: Over/Short Line Balance Procedures: Frequency ovaer/Short Line Balance: Additional Actions: Additional Actions Taken by the Operator Make notes regarding the emergency and Failure Investigation Procedures (Pressure reduction, Reinforced Squeeze Off, Clean Up. Use of Evacuators, Line Purging, closing Additional Valves, Double Block and Bleed, Continue Operating Pumps): On Sunday May 3, 2008 Atmos service technician coned off the area upon arrival, then began to try to determine gas migration patterns. Additional Atmos personnel arrived and began bar testing the area and around the structure at 2602 Syracuse Drive. The service line at 2602 Syracuse Drive was excavated, no leak was found. The bar test revealed gas concentrations in front of 2602 Syracuse Drive near the water meter. Atmos failed to continue to excavate at that point to determine origin of the leak until the Monday, May 4 at 8:55 a.m. At 11 :05 excavation revealed a leak to 2601 Syracuse Drive. On Monday, May 4, 2009 a CNG Unit was brought on-site to supply gas to the 1 customer at 2601 Syracuse Drive that was affected by the flow of gas being shut off. Three Vapor Extraction Units were brought on-site to remove gas concentrations at and around 2602 Syracuse. Additionally, service technicians continuously monitored the units from Thursday, May 7 through Monday, May 18, 2009. On Monday, May 18, 2009 the final Bar Testing reading were 0.0 percent. -14- Form 11 Pipeline Failure Investigation Fteport (Revised 03i02l0?) Pipeline Failure In vestigation Report . . (I) . I Overall Area from best possible view. Pictures from the four points of the compass. Failed Component. Operator Action, Damages in Area, Address Marki etc. Photo Roll Photo Roll N0. Descri 'on N0. N0. NO. See Attached Photo Pages. monumenth ?0 Type of Camera: Film ASA: Video Counter Log (Attach Copy): Form 11 Pipeline Failure Investigation Fleport (Revised 03i02iO7) Pipeline Failure Investigation Report Sonrces Agency Name Title Phone Number Police: Fire Dept.: Irving Fire Marshal Ken Lewallen 972-721-4856 Fire Prevention 03b?m Specialist/Investigator 972-721 4856 Stale Fire Marshall: Stale Agency: NTSB: EPA: FBI: ATF: OSHA: Insurance Co.: FRA: MMS: Television: Newspaper: Other: e15- Farm 11 Pipeline Failure Investigation Report (Revised Pipeline Failure Investigation Report Fenian: Interviewed Title Phone Number Farm 11 Pipeline Failure Investigation Report (Revised OSIUZIOT) Pipeline Failure Investigation Report Event Log Sequence ofevents prior. during. and alter the incident by time. (Consider the events of all parties involved in the incident. Fire Department and Police reports. Operator Logs and other government agencies.) Time Event Sunday, May 3, 2009 1:50 pm Irving Fire Department received First Alarm. 1:54 pm Irving Fire Department arrived on-site. 1:58 pm Atmos Energy dispatch received call from the Irving Fire Department reporting a fire and explosion. 2:02 pm Fire order dispatched to Leak Technician 2:09 pm Leak Technician en-route. 2:20 pm Leak Technician on-site. 4:00 pm Atmos Energy notifies Railroad Commission of Texas (RRC) emergency line of the incident. The incident was reported as a house fire and explosion with one injury. RRC statewide on- call person Alan Mann calls the operator to obtain additional information, then forwards the information to RRC Region 6 on-call person T.E. Sullivan. 4:35 pm Regional Railroad Commission on-call investigator T.E. Sullivan was notified of an explosion. 4:41 pm RRC investigator T.E. Sullivan received up-date from Atmos Energy on-site leak technician. 4:58 pm RRC investigator T.E. Sullivan notified RRC Division Manager and requested assistance of another inspector. 5:00 pm RRC investigator A.R. Garcia Jr. receives call to assist with incident. 5:05 pm RRC investigator T.E. Sullivan en-route. 6:05 pm RRC investigator T.E. Sullivan arrived on-site received up-dates from Atmos Energy Emergency Response Coordinator and began investigation. 6:30 pm RRC investigator A.R. Garcia arrived on-site received up-dates and began investigation. 6:40 pm RRC investigators witnessed bar testing along the main on Syracuse Drive. around the perimeter of the structured and the service line. Gas concentrations were detected. highest reading was located near the water meter box to 2602 Syracuse. 7:20 pm Began to excavate the Service Tap to 2602 Syracuse Drive. 7:30 pm RRC investigator T.E. Sullivan and Atmos Energy Technician performed an odorant test at 2602 Syracuse Drive. 0:30 pm Excavation of the 2602 Syracuse Drive Service Tap completed. 8:53 pm Atmos Energy performed a pressure test of the service line to 2602 Syracuse Drive. The pressure test held and showed no leak on the service line. 9:05 pm Atmos Energy performed a soap test at the tap to the service line to 2602 Syracuse Drive. Soap test showed no leak at the tap. 9:38 pm The riser and meter were removed from 2602 Syracuse Drive and taken into evidence by Unified Investigations 8: Sciences, Inc. 9:52 pm. RRC Investigators advised Atmos that gas concentrations were detected and a possible Grade I exists. if excavation is not performed at this time, Atmos should monitor the situation over-night. 1 1 :00 pm. RRC Investigators depart scene. Monday, May 4, 2009 2:55 am. Atmos Energy made telephonic notification to DOT {Petty Officer Johnson) #904497 -13- Form 11 Pipeline Failure Investigation Report (Revised 03/0307) Pipeline Failure Investigation Report Event Log Sequence oi" events prior. during. and after the incident by time. (Consider the events of all parties involved in the incident. Fire Department and Police reports. Operator Logs and other govemment agencies.) 8:00 a.m. Atmos began Leak Survey of Syracuse Drive with Flame Ionization Unit, detection of gas concentrations and migration were found around the structure and in the front yard and driveway to 2602 Syracuse. it was also noted the tap to 2601 Syracuse and the water meter to 2602 Syracuse are in the same general area of the highest gas concentration found. 8:55 a.m. Began excavating the tap at 2601 Syracuse 10:08 a.m. Leak found on the service line to 2601 Syracuse; subsequently Graded a Grade I 10:00 a.m. Began special leak survey of the two-block bounded area. Three grade II leaks were discovered. 12:25 p.m. Began excavation to install Stopple Fittings 8:38 p.m. Grade I was eliminated to the service line at 2601 Syracuse by isolating a section of the main with Stopple Fittings 8:45 p.m. RRC investigators departed the scene Tuesday, May 5, 2009 9:00 a.m. Began further excavation of the tap and the service line to determine the profile and elevation as it crossed the street to 2601 Syracuse. 4:21 p.m. Excavation of profile and elevation of service line to 2601 Syracuse completed. 6:22 p.m. Atmos performed a flow rate test on the service line and compression coupling to 2601 Syracuse. 9:54 p.m. Atmos? welder began preparing the four-inch main, the tap, the compression coupling and a section of the one-inch service line to weld support straps from the main to the service line to preserve and secure it as it was oriented in the ground. 11:20 p.m. Welding of the support straps was completed and Atmos technicians hand dug under and around the piping to permit cold cutting of the pipe to remove from the trench. 11:59 p.m. Atmos transferred custody of the piping to Unified Investigations 8; Sciences, Inc. Note: Additionally, throughout the day three un-repaired Grade II leaks found during the special survey were repaired by inserting a new 2603 Polyethylene service line at each location. Wednesday, May 6, 2009 12:10 a.m. Atmos pressure tested the transition from steel to polyethylene, it was tested at 17 p.s.i.g. for 10 minutes. No leaks were found. 12:55 a.m. Atmos welder began welding five-feet of four-inch steel pipe to existing main. 2:38 a.m. Welding of new section of pipe completed. 2:43 a.m. Completed insertion of new one-half inch polyethylene service line to 2601 Syracuse and pressure tested the pipe with 124 p.s.i.g. for five minutes. No leaks were found. 3:15 a.m. investigators departed scene. 8:30 a.m. - Atmos conducted a special leak survey of the two-block bounded area. No below ground 3:00 p.m. leaks were found. Thursday, May 7, through Monday, May 18, 2009 Vacuum trucks were used to extract remaining gas concentrations from 2602 Syracuse and bar testing was performed daily utilizing the same bar holes until all bar hole read a zero gas concentration. Atmos retained records of all bar tests performed. Thursday, June 4, 2009 Failure analysis testing of the Compression Coupling, pipe and service meter was performed. See Draft Protocol attached. -19- Form 11 Pipeline Failure Investigation Report (Revised 03iO2iO?) Pipeline Failure Investigation Report Event Log Sequence of events prior. during. and after the incident by time. [Consider the events of all parties involved in Ihe incident. Fire Department and Pulice reports. Operator Logs and other government agencies.) Friday, June 19, 2009 Failure analysis testing continued. Testing results showed failure of the gasket in the Normac Compression Coupling. The gasket appeared to be crimped due to improper installation or improper maintenance. Investigation Contact Log Description NIA Form 11 Pipeline Failure Investigation Report (Revised 0310207) Pipeline Failure Investigation Report Investigation Contact Log Name Description .F'ailuri.p InvestigationDooumentation Log Operator: Atmos Energy I Unit I CPF Dale: Appendix Dale FOIA Documentation Description Number Received Yes No Note: Operator records are reviewed and used to complete the report but are not retained. Note: FOIA only applies to federal agencies. A Odor Concentration Test 513/09 NIA NIA Photo Pages 0 30 Day Report NRC Report Irving Fire Department Report Unified Investigations Testing Protocol June 4, 2009 Unified Investigations Testing Protocol June 19, 2009 Field Notes of Field Bar Test Data -21.. Form 11 Pipeline Failure Investigation Report (Revised 03i02iO?) Pipeline Failure Investigation Report Failure Investigation Documentation Lag Operator: Atmos Energy Unit CPF Appendix . Dale Documentanon Number -22~ Fon'n 11 Plpeline Failure Investigation Report (Revised 03102i07) Pipeline Failure Investigation Report Site Description Provide a sketch of the area including distances from roads. houses. stress inducing factors. pipe con?gurations. etc. Bar Hole Test Survey Plot should be outlined with concentrations at test points. Photos should be taken from all angles with each pholo documented. Additional areas may be needed in any area of this guideline. 2532 2602 El i ._Poly I Service 4" oate Water Steel Main . . I . HCoated Steel Syracuse Drive r\Transition Poly 5 Service It} 2601 - .. Form 11 Pipeline Failure Investigation Report (Revised 03i02107)