On February 23, 2017, a 62-year-old section foreman was seriously injured by falling roof rock in the No. 3 entry of the active working section.  The rock fell from between roof bolts and was approximately 3 feet by 2 feet by 3 to 4 inches thick.  First-aid was administered and the injured miner was transported to a medical center.  Due to medical complications from the injuries he sustained, the victim died on April 6, 2017.

Best Practices

  • Install the most effective roof “skin” control technique, screen wire mesh, when roof bolts are installed.  Most roof fall injuries are caused by rock falling from between roof bolts (failure of the roof skin).
  • Conduct thorough examinations of the roof, face, and ribs where persons will be working and traveling; including sound and vibration testing where applicable.
  • Scale loose roof and ribs from a safe location.  Danger-off hazardous areas until appropriate corrective measures can be taken.
  • Be alert for changing conditions and report abnormal roof or rib conditions to mine management and other miners.
  • Correct all hazardous conditions before allowing persons to work or travel in such areas.  Install and examine test holes regularly for changes in roof strata.
  • Propose revisions to the roof control plan to provide measures to control roof skin hazards.
  • Know and follow the approved roof control plan and provide additional support when cracks or other abnormalities are detected.  Remember, the approved roof control plan contains minimum requirements.

Click here for: MSHA Preliminary Report (pdf)

On January 25, 2017, a miner was found in an underground limestone mine after failing to exit the mine at the end of the shift.  The miner was located under material that had fallen from the rib in an area of the mine that had been barricaded to prevent entry due to bad roof and rib conditions.

Best Practices

  • Install barriers to impede unauthorized entry into areas where unattended hazardous ground conditions exist.
  • Establish procedures to account for miners in all areas of the mine – surface, underground, shops, and facilities – across and at the end of shifts.
  • Do not cross barriers that are intended to prevent access to dangered-off areas of underground mines.
  • Train miners to recognize potentially hazardous ground conditions and to understand safe job procedures for elimination of the hazards.
  • Never enter hazardous areas that have been dangered-off or otherwise identified to prohibit entry.
  • Develop and train miners on a method that clearly alerts miners not to enter hazardous areas.
  • If possible, do not work alone. If working alone, communicate intended movements to a responsible person.

Click here for: MSHA Preliminary Report (pdf)

c02.jpgOn February 20, 2015, a 29-year-old roof bolter helper with 3 years and 48 weeks of mining experience was killed when a piece of rock approximately 3 feet wide, 11½ feet long, and 3 to 16 inches thick fell and pinned him against the top of the drill canopy of a roof bolting machine.  The roof bolting machine was positioned to install the next row of permanent supports when the accident occurred.

Best Practices

  • Visually examine the roof, face, and ribs immediately before any other work is started in the area.
  • Be alert to changing conditions, especially after activities that could cause roof disturbance.
  • While under supported roof, perform sound and vibration tests where roof supports are to be installed.
  • Establish in the roof control plan a bolt installation pattern that effectively supports the roof strata.
  • Adequately support or scale down any loose roof or rib material from a safe location.
  • Ensure that ATRS systems on all roof bolting machines are maintained in good working condition.  Ensure the ATRS sets firmly against the mine roof, as specified by the manufacturer, before installing new roof supports.
  • As much as possible, stay under the roof bolting machine’s drill canopy when working in the area between the ATRS and the last row of permanent roof supports.
  • Take additional measures when hazards associated with draw rock are encountered, such as mining shorter cuts and decreasing roof bolt spacing.
  • When using roof screen, implement work procedures that incorporate positioning and securing the mesh from a safe location.
  • Know and follow the approved roof control plan.  Install and examine test holes regularly to check for changes in roof strata.
  • Add additional supports at any indication of adverse roof conditions.

Click here for: MSHA Preliminary Report (pdf)

14c14On Monday, November 10, 2014, at approximately 9:35 p.m., a 49-year-old section foreman with 27 years of mining experience was killed when he was struck by a large rock that measured 5 feet by 3 feet by 13 inches thick.  The victim was operating the roof bolting machine on the 2 North section in the No. 2 entry at the time of the accident.  The rock fell inby the last full row of permanent roof supports and between the automated temporary roof support (ATRS) and the left rib.

Best Practices
  • Perform a visual examination of the roof, face, and ribs immediately before any other work is started in the area.
  • Be alert to changing conditions, especially after activities that could cause roof disturbance.
  • While under supported roof, perform sound and vibration tests where roof supports are to be installed.
  • Adequately support or scale down any loose roof or rib material from a safe location.
  • Ensure that ATRS systems on all roof bolting machines are maintained in good working condition and set firmly against the mine roof before installing new roof supports.
  • Ensure ATRS are set within 5 feet of permanent support as well as within 5 feet of the rib line.
  • Stay under the roof bolting machine canopy when working in the area between the ATRS and the last row of permanent roof support.
  • Ensure that the approved roof control plan is followed and is suitable for the geologic conditions encountered at the mine.  If conditions change and cause the plan to no longer be suitable, the plan must be revised to provide adequate support for the control of the roof face and ribs.

Click here for: MSHA Preliminary Report (pdf)

ftl2013c08On Friday, March 22, 2013, a 29-year old continuous mining machine operator, with 9 years of mining experience, was killed while operating a remote-controlled continuous mining machine during retreat mining. While mining a left hand lift, the victim and his helper were positioned near the right rear corner of the continuous mining machine and the right rib. A section of roof, approximately 8 feet long by 7 feet wide and 16 inches thick, fell and broke several roof bolts. The fallen rock struck the victim and knocked down the victim’s helper, injuring him. The slab of rock that fell was a portion of a larger fall, approximately 20 feet wide by 25 feet long, that included the bolted roof between the rear of the continuous mining machine and the mobile roof support units located inby.

Best Practices

  • Ensure that the approved Roof Control Plan support provisions are suitable for the geological conditions at the mine and that the plan is followed.
  • Develop a map of geologic features, so additional support can focus on those areas.
  • Conduct frequent and adequate examinations of roof, face, and ribs. Be alert for changing conditions. When hazardous conditions are detected, danger off access to the area until it is made safe for work and travel.
  • Maintain proper entry widths and pillar dimensions.
  • Develop a safe procedure to align Mobile Roof Supports with the lift being mined.
  • Install and examine test holes regularly for changes in roof strata.
  • Take additional measures when hazards associated with draw rock are encountered, such as mining shorter cuts and decreasing roof bolt spacing.
  • When joints are encountered, install adequate supplemental support.

Click here for: MSHA Preliminary Report (pdf), MSHA Investigation Report (pdf).

ftl2013c07On Wednesday, March 13, 2013, at approximately 4:55 p.m., a 63-year-old roof bolter with 40 years of mining experience was killed when he was struck by a large piece of roof rock while installing a rib bolt on the right side of the number 8 right crosscut on the No. 1 Section. The victim was between the drill head and the ATRS when the roof fell on him. The rock was approximately 6 feet long by 5.5 feet wide and about 5 inches thick.

Best Practices

  • Conduct frequent and adequate examinations of the roof, face, and ribs. Be alert for changing conditions at all times. When hazardous conditions are detected, danger off access to the area until it is made safe for work and travel.
  • Develop and follow safe rib bolting procedures. Consult the manufacturer’s recommendations.
  • Adequately support, or scale down, any loose roof or rib material from a safe location before working or traveling in the area.
  • Ensure that Automated Temporary Roof Support (ATRS) systems on all roof bolting machines are maintained in good working condition.
  • Ensure that the approved Roof Control Plan is followed and is suitable for the geologic conditions encountered at the mine. If conditions change and cause the plan to no longer be suitable, the plan must be revised to provide adequate support for the control of the roof, face, and ribs.

Click here for: MSHA Preliminary Report (pdf), MSHA Investigation Report (pdf).

On Wednesday, September 26, 2012, a 32-year old section foreman with 12 years of experience was killed by a roof fall at Kopper Glo Mining’s Double Mountain Mine. He was operating the continuous mining machine to excavate a roof cavity in preparation for the installation of a belt conveyor drive. The foreman was positioned approximately 8 feet inby the last row of permanent roof support when a section of the unsupported roof, approximately 6½ feet long, by 6 feet wide, by up to 8 inches thick fell, striking the victim and pinning him to the mine floor.

Best Practices
  • Always post the end of permanent roof support with a readily visible warning or physical barrier to impede travel beyond permanent roof support. This serves to alert all miners as they approach a danger zone.
  • Never travel beyond permanent roof support.
  • Never expose any portion of your body inby the last row of undisturbed permanent roof supports.
  • Make frequent, thorough roof examinations and be aware of changing roof conditions at all times.
  • Give extra attention to the roof after activities that cause roof disturbance.
  • Take extra precautions when cutting out roof support or mining above the normal roof line, such as mining a shorter depth of cut, then install two rows of roof bolts before continuing to mine.

Click here for: MSHA Preliminary Report (pdf), MSHA Investigation Report (pdf).

On Thursday, September 13, 2012, a 61-year-old general inside laborer with 38 years of mining experience was killed when he was struck by a section of mine roof. The victim was removing a roof bolt from an older area of the mine which was no longer in contact with the mine roof. A section of mine roof fell, striking the victim.

Best Practices
  • Before performing work in any area of the mine, observe the roof and ribs for hazardous conditions and correct hazards immediately.
  • Install additional roof supports prior to removing old supports.
  • Perform sound and vibration testing before installing or removing permanent roof supports.
  • Only remove roof supports under the direction of a manager or foreman.
  • Use roof screen (wire mesh) to control loose roof in long-term travel roads.
  • Take extra precautions when working or traveling in older areas of the mine, paying particular attention to deteriorating roof conditions.
  • Make frequent roof examinations and be alert to changing roof conditions at all times. Give extra attention to the roof after activities occur that could cause roof disturbance.

Click here for: MSHA Preliminary Report (pdf), MSHA Investigation Report (pdf).

On Monday, August 15, 2011, a 46 year old miner was killed when he was struck by a portion of the mine roof that fell from an area adjacent to a longwall shield. The accident occurred during a longwall move, while the victim was installing a wooden crib in an area where a longwall face shield had been removed previously. The victim had approximately five years experience with this activity.

Best Practices
  • Assure that roof control plans are suitable to the prevailing geological conditions. If roof geology changes affect roof stability, reevaluate roof support techniques.
  • Share and discuss roof control plans with the miners on a regular basis. For miner safety, assure that the roof control plan safety precautions are followed.
  • Provide additional training for specialized work, such as longwall moves, emphasizing best practices for a specific task.
  • Conduct examinations of roof conditions frequently to prevent exposure to poor roof conditions. Remain vigilant for changing roof conditions.
  • When hazardous roof conditions are detected, danger off areas until they are made safe.
Click here for: MSHA Preliminary Report (pdf), MSHA Investigation Report (pdf).

On April 25, 2011, a 31 year- old drill operator with 6 weeks of experience was killed at an underground crushed stone operation. He was walking in a crosscut when a slab of roof, approximately 5 feet wide by 6 feet long by 10 inches thick, struck him.

Best Practices

  • Train persons to identify work place hazards and take action to correct them.
  • Design, install, and maintain a support system to control the ground in places where persons work or travel.
  • Examine and test ground conditions in areas where work is to be performed prior to work commencing and as ground conditions warrant during the shift.
  • When ground conditions create a hazard to persons, install additional ground support before other work is permitted in the affected area.
  • Be alert to any change of ground conditions.

Click here for: MSHA Preliminary Report (pdf), MSHA Investigation Report(pdf), Overview(powerpoint), Overview (pdf).