Failure Report-Enbridge Energy LP 2/19/04

Page 1Official PDFMemorandum U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration Central Region Office Office of Pipeline Safety Date: September 30, 2010 Subject: Summary Incident Report Enbridge Energy Partners L.P. (Op ID 11169) Deer River, MN to Floodwood, MN (Unit 3083) Line 2 Crude Oil Leak February 19, 2004 SMART Activity 110735 From: James Bunn, Staff Engineer original signed To: David Barrett, Director – Central Region, PHP-300 original signed 1.0 SUMMARY At approximately 12:52 p.m. on February, 19 2004, Enbridge Energy Partners L.P. (“Enbridge”) discovered a crude oil leak on their Line 2 Pipeline in Itasca County, Grand Rapids, MN (the “Incident”). An estimated 1003 barrels (bbls) of crude oil was released from the pipeline. The Incident occurred on the pipeline right of way (ROW) near milepost number 1007 (MP 1007), northwest of the City of Grand Rapids, MN. No fatalities or injuries occurred as a result of the Incident. The Incident did occur in a high consequence area (HCA), drinking water (DW) and other populated area (OPA) was impacted. The total cost of the Incident, pipeline repair and environmental cleanup, is estimated at $1,100,000. There were no service interruptions or supply impacts as a result of the Incident. 2.0 PIPELINE SYSTEM Enbridge’s Line 2 is a 26-inch diameter crude oil pipeline that runs from Gretna, Manitoba, Canada to Superior, WI. At the Incident location, the pipeline is constructed of API 5L X-52 line pipe manufactured by A.O. Smith in 1956. The pipeline is 26-inch diameter by 0.281-inch wall thickness, electric flash welded (EFW) type pipe, coated with a coal tar enamel system. Page | 1#

Page 2The Line 2 maximum operating pressure (MOP) is 809 psig. 3.0 DISCUSSION An Enbridge maintenance crew excavating an in-line inspection (ILI) indication discovered the crude oil leak. At 12:52 p.m. Enbridge Notified the Minnesota Office of Pipeline Safety (MNOPS) Duty Officer that a leak had occurred. Brian Pierzina, MNOPS Senior inspector, conducted an on-site investigation of the Incident. In September 2003, Enbridge ran an in-line inspection (ILI) magnetic flux leakage (MFL) and geometry tool through this portion of Line 2. The ILI tool identified a potential dent with metal loss at MP 1007. Enbridge scheduled excavation of the MP 1007 indication for February of 2004. During the indication excavation, oily soil was discovered. As the excavation continued, signs of fresh product were encountered. Once it was determined that the pipeline was most likely leaking at MP 1007, the pipeline was shut down. In situ visual inspection of the damaged pipe joint revealed a 2-inch long through wall crack in the pipe body. A small amount of oil was leaking through the crack. The crack was located in a dent on the bottom of the pipe. A rock was identified in the backfill under the pipe. The rock location was coincident with the dent. The rock was eventually removed from under the pipeline. 4.0 EMERGENCY RESPONSE Enbridge employees were dispatched to the Incident site. Once the repair was completed and inspected the contaminated soil and ground water was remediated. 5.0 RETURN TO SERVICE The pipeline was shut down at approximately 11:30 a.m. on February 20, 2004. After the field investigation was complete, a one foot long Type B, tight fitting repair sleeve was installed in the area where the Incident occurred. At the time of the Incident, Line 2 operating pressure was approximately 750 psig. No reduction in operating pressure was required as a result of this incident. The pipeline was returned to service at approximately 10:30 p.m. on February 20, 2004. Page | 2#

Page 36.0 FINDINGS The Enbridge Line 2 MP 1007 Incident was caused by a crack located within a dent that initiated on the pipe external surface. The crack was apparently caused by a rock found in the backfill at the location of the dent. EXHIBITS Information regarding the Incident was reported by Enbridge to the National Response Center (NRC) on March 2, 2004 in NRC Report No. 714880 (Exhibit A), and to the Pipeline and Hazardous Materials Safety Administration (PHMSA) in Accident Report No. 20040063 dated March 16, 2004 (Exhibit B). Exhibit A NRC Report No.714880 Exhibit B Accident Report No. 20040063 Page | 3#

Page 4EXHIBIT A NRC REPORT No. 714880#

Page 5Page 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 # 714880 INCIDENT DESCRIPTION *Report taken at 12:28 on 02-MAR-04 Incident Type: PIPELINE Incident Cause: EQUIPMENT FAILURE Affected Area: The incident occurred on 19-FEB-04 at 11:30 local time. Affected Medium: SOIL ____________________________________________________________________________ SUSPECTED RESPONSIBLE PARTY Organization: ENBRIDGE ENERGY CO. SUPERIOR, WI 54880 Type of Organization: PRIVATE ENTERPRISE ____________________________________________________________________________ INCIDENT LOCATION County: ITASCA City: GRAND RAPIDS State: MN Distance from City: Direction from City: N MILEPOST 1007.33 NEAR 20TH ST. NW AND 8TH AVE ____________________________________________________________________________ RELEASED MATERIAL(S) CHRIS Code: OIL Official Material Name: OIL: CRUDE Also Known As: Qty Released: 10 BARREL(S) ____________________________________________________________________________ DESCRIPTION OF INCIDENT MATERIAL RELEASED FROM A 26" PIPELINE DUE TO A DENT WITH A CRACK IN THE LINE. ____________________________________________________________________________ INCIDENT DETAILS Pipeline Type: TRANSMISSION DOT Regulated: YES Pipeline Above/Below Ground: BELOW Exposed or Under Water: NO Pipeline Covered: UNKNOWN ____________________________________________________________________________ DAMAGES Fire Involved: NO Fire Extinguished: UNKNOWN INJURIES: NO Hospitalized: Empl/Crew: Passenger: FATALITIES: NO Empl/Crew: Passenger: Occupant: EVACUATIONS: NO Who Evacuated: Radius/Area: Damages: YES $55000 Length of Direction of Closure Type Description of Closure Closure Closure Air: N Road: N Waterway: N Track: N Major Artery: N http://www.nrc.uscg.mil/reports/rwservlet?standard web+inc _ _ seq=714880 10/7/2010#

Page 6Page 2 of 2 Passengers Transferred: UNKNOWN Environmental Impact: UNKNOWN Media Interest: NONE Community Impact due to Material: NO ____________________________________________________________________________ REMEDIAL ACTIONS EXCAVATED SOIL, CLEANUP COMPLETED Release Secured: YES Release Rate: Estimated Release Duration: ____________________________________________________________________________ WEATHER Weather: CLEAR, ºF ____________________________________________________________________________ ADDITIONAL AGENCIES NOTIFIED Federal: State/Local: MN DUTY OFFICER, MN PCA, MN OPS State/Local On Scene: State Agency Number: 57773 ____________________________________________________________________________ NOTIFICATIONS BY NRC ATSDR MN (PRIMARY) 02-MAR-04 12:35 U.S. EPA V (PRIMARY) 02-MAR-04 12:37 NOAA 1ST CLASS BB RPTS FOR MN (PRIMARY) 02-MAR-04 12:35 RSPA OFFICE OF PIPELINE SAFETY (PRIMARY) 02-MAR-04 12:42 MN DEM ATTN: MS. GOELZ (PRIMARY) 02-MAR-04 12:35 ____________________________________________________________________________ ADDITIONAL INFORMATION CALLER HAD NO ADDITIONAL INFORMATION. ___________________________________________________________________________ *** END INCIDENT REPORT # 714880 *** http://www.nrc.uscg.mil/reports/rwservlet?standard web+inc _ _ seq=714880 10/7/2010#

Page 7EXHIBIT B ACCIDENT REPORT No. 20040063#

Page 8NOTICE: This report is required by 49 CFR Part 195. 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 60122 OMB No. 2137-0047 U.S. Department of Transportation Research and Special Programs Administration ACCIDENT REPORT – HAZARDOUS LIQUID PIPELINE 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 Original Report Supplemental Report Final Report 1. a. Operator's OPS 5-digit Identification Number (if known) / ____________/ 2. b. If Operator does not own the pipeline, enter Owner’s OPS 5-digit Identification Number (if known) / ___ / c. Name of Operator ______________________________________________________________________________________ d. Operator street address _______________________________________________________________________________ e. Operator address ______________________________________________________________________________________ City, County, State and Zip Code IMPORTANT: IF THE SPILL IS SMALL, THAT IS, THE AMOUNT IS AT LEAST 5 GALLONS BUT IS LESS THAN 5 BARRELS, COMPLETE THIS PAGE ONLY, UNLESS THE SPILL IS TO WATER AS DESCRIBED IN 49 CFR §195.52(A)(4) OR IS OTHERWISE REPORTABLE UNDER §195.50 AS REVISED IN CY 2001. 2. Time and date of the accident / / / / / / / / hr. month day year 3. Location of accident (If offshore, do not complete a through d. See Part C.1) a. Latitude: _____ Longitude: __________ (if not available, see instructions for how to provide specific location) b. _________________________________________________ City, and County or Parish c. _________________________________________________ State and Zip Code d. Mile post/valve station or survey station no. (whichever gives more accurate location) _________________________________ 4. Telephone report / / / / / / / / 5. Losses (Estimated) Public/Community Losses reimbursed by operator: Public/private property damage $_______________ Cost of emergency response phase $_______________ Cost of environmental remediation $_______________ Other Costs $_______________ (describe) _____________________________________ Operator Losses: Value of product lost $_______________ Value of operator property damage $_______________ Other Costs $_______________ (describe) _____________________________________ Total Costs $_______________ NRC Report Number month day year 6. Commodity Spilled Yes No (If Yes, complete Parts a through c where applicable) a. Name of commodity spilled ___________________________ b. Classification of commodity spilled: HVLs /other flammable or toxic fluid which is a gas at ambient conditions CO2 or other non-flammable, non-toxic fluid which is a gas at ambient conditions Gasoline, diesel, fuel oil or other petroleum product which is a liquid at ambient conditions Crude oil c. Estimated amount of commodity involved : Barrels Gallons (check only if spill is less than one barrel) Amounts: Spilled : ____________ Recovered: ____________ CAUSES FOR SMALL SPILLS ONLY (5 gallons to under 5 barrels) : (For large spills [5 barrels or greater] see Part H) Corrosion Natural Forces Excavation Damage Other Outside Force Damage Material and/or Weld Failures Equipment Incorrect Operation Other PART B – PREPARER AND AUTHORIZED SIGNATURE (type or print) Preparer's Name and Title Area Code and Telephone Number Preparer's E-mail Address Area Code and Facsimile Number Authorized Signature (type or print) Name and Title Date Area Code and Telephone Number Form RSPA F 7000-1 ( 01-2001 ) Page 1 of 4 OPS Data Facsimile#

Page 9PART C – ORIGIN OF THE ACCIDENT (Check all that apply) 1. Additional location information a. Line segment name or ID _______________________ b. Accident on Federal land other than Outer Continental Shelf Yes No c. Is pipeline interstate? Yes No Offshore: Yes No (complete d if offshore) d. Area ___________________ Block # ______________ State / / or Outer Continental Shelf 2. Location of system involved (check all that apply) Operator’s Property Pipeline Right of Way High Consequence Area (HCA)? Describe HCA____________________________________ 3. Part of system involved in accident Above Ground Storage Tank Cavern or other below ground storage facility Pump/meter station; terminal/tank farm piping and equipment, including sumps Other Specify: _________________________________ Onshore pipeline, including valve sites Offshore pipeline, including platforms If failure occurred on Pipeline, complete items a - g: 4. Failure occurred on Body of Pipe Pipe Seam Scraper Trap Pump Sump Joint Component Valve Metering Facility Repair Sleeve Welded Fitting Bolted Fitting Girth Weld Other (specify) Year the component that failed was installed: / / 5. Maximum operating pressure (MOP) a. Estimated pressure at point and time of accident: ____ PSIG b. MOP at time of accident: ___________PSIG c. Did an overpressurization occur relating to the accident? Yes No a. Type of leak or rupture Leak: Pinhole Connection Failure (complete sec. H5) Puncture, diameter (inches) _________ Rupture: Circumferential – Separation Longitudinal – Tear/Crack, length (inches) __________ Propagation Length, total, both sides (feet) _________ N/A Other _______________________________ b.Type of block valve used for isolation of immediate section: Upstream: Manual Automatic Remote Control Check Valve Downstream: Manual Automatic Remote Control Check Valve c. Length of segment isolated _______ ft d. Distance between valves _______ ft e. Is segment configured for internal inspection tools? Yes No f. Had there been an in-line inspection device run at the point of failure? Yes No Don’t Know Not Possible due to physical constraints in the system g. If Yes, type of device run (check all that apply) High Resolution Magnetic Flux tool Year run: ______ Low Resolution Magnetic Flux tool Year run: ______ UT tool Year run: ______ Geometry tool Year run: ______ Caliper tool Year run: ______ Crack tool Year run: ______ Hard Spot tool Year run: ______ Other tool Year run: ______ PART D – MATERIAL SPECIFICATION PART E – ENVIRONMENT 1. Nominal pipe size (NPS) / / in. 2. Wall thickness / / in. 3. Specification SMYS / / 4. Seam type 5. Valve type 6. Manufactured by in year / / 1. Area of accident In open ditch Under pavement Above ground Underground Under water Inside/under building Other ____________ 2. Depth of cover: inches PART F – CONSEQUENCES 1. Consequences (check and complete all that apply) a. Fatalities Injuries c. Product ignited Yes No d. Explosion Yes No Number of operator employees: _______ _______ e. Evacuation (general public only) / / people Contractor employees working for operator: _______ _______ Reason for Evacuation: General public: _______ _______ Precautionary by company Totals: _______ _______ Evacuation required or initiated by public official b. Was pipeline/segment shutdown due to leak? Yes No f. Elapsed time until area was made safe: If Yes, how long? ______ days ______ hours _____ minutes / / hr. / / min. 2. Environmental Impact a. Wildlife Impact: Fish/aquatic Yes No e. Water Contamination: Yes No (If Yes, provide the following) Birds Yes No Amount in water _________ barrels Terrestrial Yes No Ocean/Seawater No Yes b. Soil Contamination Yes No Surface No Yes If Yes, estimated number of cubic yards: _________ Groundwater No Yes c. Long term impact assessment performed: Yes No Drinking water No Yes (If Yes, check below.) d. Anticipated remediation Yes No Private well Public water intake If Yes, check all that apply: Surface water Groundwater Soil Vegetation Wildlife Form RSPA F 7000-1 ( 01-2001 ) Page 2 of 4 OPS Data Facsimile#

Page 10PART G – LEAK DETECTION INFORMATION 1. Computer based leak detection capability in place? Yes No 2. Was the release initially detected by? (check one): CPM/SCADA-based system with leak detection Static shut-in test or other pressure or leak test Local operating personnel, procedures or equipment Remote operating personnel, including controllers Air patrol or ground surveillance A third party Other (specify) _________________ 3. Estimated leak duration days ____ hours ____ PART H – APPARENT CAUSE Important: There are 25 numbered causes in this Part H. Check the box corresponding to the primary cause of the accident. Check one circle in each of the supplemental categories corresponding to the cause you indicate. See the instructions for guidance. b. Visual Examination Localized Pitting General Corrosion Other ____________________ H1 – CORROSION a. Pipe Coating c. Cause of Corrosion 1. External Corrosion Bare Galvanic Atmospheric Coated Stray Current Microbiological Cathodic Protection Disrupted 2. Internal Corrosion Stress Corrosion Cracking Selective Seam Corrosion (Complete items a – e Other ____________________ where applicable.) d. Was corroded part of pipeline considered to be under cathodic protection prior to discovering accident? No Yes, Year Protection Started: / / e. Was pipe previously damaged in the area of corrosion? No Yes => Estimated time prior to accident: / / years / / months Unknown H2 – 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 H3 – EXCAVATION DAMAGE 8. Operator Excavation Damage (including their contractors/Not Third Party) 9. Third Party (complete a-f) a. Excavator group General Public Government Excavator other than Operator/subcontractor b. Type: Road Work Pipeline Water Electric Sewer Phone/Cable Landowner-not farming related Farming Railroad Other liquid or gas transmission pipeline operator or their contractor Nautical Operations Other ________ c. Excavation was: Open Trench Sub-strata (boring, directional drilling, etc…) d. Excavation was an ongoing activity (Month or longer) Yes No If Yes, Date of last contact /_________/ e. Did operator get prior notification of excavation activity? Yes; Date received: / / mo. / / day / ______/ yr. No Notification received from: One Call System Excavator Contractor Landowner f. Was pipeline marked as result of location request for excavation? No Yes (If Yes, check applicable items i - iv) i. Temporary markings: Flags Stakes Paint ii. Permanent markings: iii. Marks were (check one) : Accurate Not Accurate iv. Were marks made within required time? Yes No H4 – 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 7000-1 ( 01-2001 ) Page 3 of 4 OPS Data Facsimile#

Page 11H5 – MATERIAL AND/OR WELD FAILURES Material 14. Body of Pipe => Dent Gouge 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 H5. 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 accident occurred? Yes, complete d-g No d. Date of test: / / yr. / / mo. / / day e. Test medium: Water Inert Gas Other f. Time held at test pressure: / / hr. g. Estimated test pressure at point of accident: PSIG H6 – EQUIPMENT 20. Malfunction of Control/Relief Equipment => Control valve Instrumentation SCADA Communications Block valve Relief valve Power failure Other 21. Threads Stripped, Broken Pipe Coupling => Nipples Valve Threads Dresser Couplings Other 22. Seal Failure => Gasket O-Ring Seal/Pump Packing Other H7 – INCORRECT OPERATION 23. Incorrect Operation a. Type: Inadequate Procedures Inadequate Safety Practices Failure to Follow Procedures Other _______________________________________ b. Number of employees involved who failed a post-accident test: drug test: / / alcohol test /_________/ H8 – OTHER 24. Miscellaneous, describe: 25. Unknown Investigation Complete Still Under Investigation (submit a supplemental report when investigation is complete) PART I – NARRATIVE DESCRIPTION OF FACTORS CONTRIBUTING TO THE EVENT (Attach additional sheets as necessary) Form RSPA F 7000-1 (01-2001 ) Page 4 of 4 OPS Data Facsimile#