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46-08436

46-08436. April 5, 2010 Upper Big Branch Mine Disaster – Ongoing January 18, 2011 Update. Status of Underground Investigation Interviews Conducted MSHA Personnel Involved Events Leading Up to Explosion Shift Prior to Explosion April 5, 2010: Longwall – Day Shift

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46-08436

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  1. 46-08436

  2. April 5, 2010 Upper Big Branch Mine Disaster – OngoingJanuary 18, 2011 Update • Status of Underground Investigation • Interviews Conducted • MSHA Personnel Involved • Events Leading Up to Explosion • Shift Prior to Explosion • April 5, 2010: Longwall – Day Shift • Location of Deployed SCSR Units • Ventilation Issues • Fuel • Possible Ignition Sources

  3. Status of Underground Investigation • Accident Investigation began April 12, 2010. • Underground Investigation began June 25, 2010. • Nearing Completion • Recent Delays • Pumping Water from TG 22 and HG 22 • Establishing Water to the Shearer

  4. Interviews Conducted • 261 Individuals have been interviewed as of January 18, 2011 • 18 Individuals exercised their 5th Amendment Rights • The investigation team is continuing interviews

  5. MSHA Personnel Involved • 105 MSHA Investigation Personnel have been utilized during the on-site investigation Type and Number of Teams Utilized • 10 Mine Dust Survey Teams • 7 Mapping Teams • 3 Electrical Teams • 1 Ventilation Team • 1 Geology Team • 1 Flames and Forces Team • 1 Evidence Collection Team • Inspection Activities Team • An additional 45 Technical Support Personnel were utilized to perform testing and other technical activities • Also 25 EFS, 7 SM, and 9 EPD Personnel were utilized to guard the three portals during the investigation

  6. Events Leading Up to Explosion

  7. 1 North Development • As per the mine map, originally developed as Room and Pillar entries • Converted to L/W Panel • 1 North HG Developed ground controls issues

  8. Easter Weekend • C/M miner sections did not produce coal on Easter weekend • Longwall produced coal on Saturday (4/3/10) • Entire Mine idle on Sunday (4/4/10)

  9. Shift Prior to Explosion

  10. 4-5-2010 L/W 3rd Shift (Midnight Shift) • Maintenance Shift Only (No Production) • Various items remain under investigation

  11. April 5, 2010Longwall - Day Shift

  12. UBB Longwall Day Shift Summary • First Call Out at 7:30 a.m. • Longwall ran until 11:00 a.m. and had made 2 passes • Longwall was down from approximately 11:00 a.m. to as late as 2:15 p.m. • Longwall may have been tested following repairs between 1:30 p.m. and 2:00 p.m. A total of 2.2 passes was reported. • Shearer was down due to Lost B-Lock on Ranging Arm • B-Lock is the retainer for the hinge pin that holds the ranging arm in place • Call Out at 2:30 p.m. • Shearer at Shield 115 going toward tailgate • The Pre-shift Report was called out at 2:40 p.m.

  13. Location of Deployed SCSR Units

  14. Ventilation Issues

  15. UBB Ventilation Issues The official 75.1200 map identified by company was not up to date. During the mapping portion of the investigation, stopping remnants were identified and plotted on a map.

  16. To Date, Belt Examination Records Indicate

  17. Fuel

  18. Methane • Based on the analysis of the evidence collected thus far, it appears that a low Volume of Methane and/or Methane from Natural Gas provided the fuel for the initial ignition on or near the face on the tailgate side of the longwall. • No evidence to date of flame on the tailgate end of the longwall face • No evidence to date of coking on the tailgate end of the longwall face

  19. To date the analysis of the evidence shows that a small Methane/Methane from Natural Gas Ignition transitioned into a Massive Coal Dust Explosion

  20. Post Explosion Dust Sampling Results Face

  21. Possible Ignition Sources

  22. Status of Electrical Testing • All electrical components have been tested and checked for possible ignition sources. • At this time no electrical ignition sources have been identified.

  23. Testing of Handheld Methane Detectors

  24. Introduction to the Solaris Handheld Multi-Gas Detector • Handheld detectors were in use that recorded data.  These were the MSA Solaris Multigas Detectors.  These devices included: • a combustible gas sensor (used to detect methane), • an oxygen sensor, • a carbon monoxide sensor, and, in some cases, • an nitrogen dioxide sensor.. • A total of 3 Solaris Handheld Detectors recorded similar data • One detector was found on the longwall face • One detector was approximately 3600 feet from the longwall (Near Mother Drive) • One detector was approximately 6000 feet from the longwall (Near Mantrip at Crosscut 68)

  25. Testing of Solaris Handheld Methane Detectors • The ‘Combustible Gas Sensor’ in the Solaris will respond to methane and other combustible gases. • Once the instrument detects any combustible gas mixture equivalent to 5% of methane, the power to this sensor shuts down and the data latches at 5%. • Byproduct gases of an explosion such as Ethylene, Acetylene, Carbon Monoxide and Hydrogen can appear on these instruments as Methane.

  26. Potential Frictional Ignition Sources • Longwall Shearer • Worn Bits • Missing Water Sprays • Other Ignition Possibilities

  27. Video of Tailgate Drum as it was found with 4 visible sprays missing. (Click on Picture to Start Video Clip) Water Pressure on Shearer is 150 PSI.

  28. (Click on Picture to Start Video Clip)

  29. Investigation On-Going • Additional Investigation Activities to be Completed • Interviews • Remove HG 22 Mantrip • Verify Facts of Findings during UG Investigation • Longwall Face will also be revisited for various purposes

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