DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
District 4
REPORT OF INVESTIGATION
(UNDERGROUND COAL MINE)
FATAL POWERED-HAULAGE ACCIDENT
Still Run #4, ID No. 46-08726
Century Energy Corporation
Itmann, Wyoming County, West Virginia
October 24, 2000
By
William Uhl, Jr.
Coal Mine Safety and Health Inspector
Michael G. Kalich
Coal Mine Safety and Health Inspector (Electrical)
Originating Office - Mine Safety and Health Administration
100 Bluestone Road, Mount Hope, West Virginia 25880
Edwin P. Brady, District Manager
Overview
On Tuesday, October 24, 2000, a 37-year-old mobile-bridge operator, with seven years mining experience, was fatally injured when he was crushed between the coal rib and the No. 3 mobile- bridge carrier he was operating. This system consists of four mobile-bridge carriers. There were no eyewitnesses to the accident. The accident occurred as the mobile-bridge system was changing places to begin mining in a different entry.
General Information
The Still Run No. 4 mine, operated by Century Energy Corp., is located near Itmann, Wyoming County, West Virginia. The mine was formerly operated by Bell Holding, Inc. A letter for adoption of all plans, permits, and waivers was received August 30, 2000. Rehabilitation work commenced September 2, 2000, and coal production resumed October 2, 2000. The single section mine is developed into the Fire Creek seam through five drift openings. The coal seam thickness averages 48 inches. Approximately 800 tons of clean coal are produced daily on three production shifts by a total of 39 employees. The mining method used is room and pillar with coal extraction and haulage utilizing continuous miners, mobile-bridge conveyors, and belt conveyors. The blowing mine ventilation fan produces 89,000 cubic feet per minute (cfm). There is negligible methane liberation.
Mine officials for Century Energy Corp. are as follows:
James E. Trent PresidentA AAA inspection was ongoing at the time.
Robert J. Toler Secretary
Kenneth Bowles Superintendent
Jimmy Williams Mine Foreman
Description of the Accident
On Tuesday, October 24, 2000, the evening shift production crew, under the direction of section foreman, Charles Halsey, entered the mine at 3:00 p.m. The day shift crew had been mining in the crosscut off the No. 1 entry at the end of their shift when electrical problems occurred on the mobile-bridge conveyor system. The evening shift electrician located the problem and repaired the trailing cable for the mobile-bridge conveyor. The bridge system was then moved to the face of the No. 5 entry to begin the first cut mined on the evening shift.
Upon completion of mining in the No. 5 entry, the bridge system was backed outby and across the second open line of crosscuts towards the No. 2 entry. The continuous mining machine was moved to the face of the No. 4 entry, and the bridge system proceeded to tram toward the No. 4 entry.
There are four mobile-bridge conveyors and operators that make up this system. They are identified as Bridges No. 1, 2, 3, and 4, respectively, with No. 1 being the bridge at the section low belt conveyor tail piece and the No. 4 bridge being located behind the continuous miner. The four bridges are hinged together but are not attached to the continuous miner. Movement of the individual bridge sections can cause the other bridge sections to be pulled or pushed.
The No. 4 bridge operator had pulled to within a few feet of the continuous mining machine. He then exited his cab and hooked up the water line for the continuous miner. The water line runs with the mobile bridge conveyor system, with a valve and quick coupler located on the No. 4 bridge.
The continuous-mining-machine operator and the section foreman were located near the right inby corner of the No. 4 intersection. Two roof-bolter operators and the bolting machine were located in the crosscut between the No. 4 and No. 5 entries. The bolting crew was loading supplies and making up roof bolts. Charles Halsey, section foreman, and the continuous-mining-machine operator stated that at approximately 4:45 p.m., the time the No. 4 bridge operator hooked up the water line and re-entered his operator's compartment, someone outby began shouting for Halsey indicating that the No. 3 bridge operator was caught between the coal rib and the bridge. Section foreman Halsey immediately ran to the victim and determined that he was seriously injured. Halsey dispatched crew members to obtain first-aid supplies, a mantrip, and to call for an ambulance. Halsey stated that being familiar with the mobile-bridge conveyor system, he realized the best means to prevent further injury to the victim, Richard Anderson, was to energize the No. 3 bridge and split the tram controls which caused the bridge to swing away from the victim. This action freed Anderson.
The section EMT assisted by Halsey, administered first-aid to the victim, secured him to a stretcher, and immediately transported him to the surface by rubber-tired battery mantrip. The Upper Laurel Ambulance Service of Pineville, West Virginia, arrived at the mine approximately two minutes after the victim reached the surface. The victim was immediately transported to Raleigh General Hospital, Beckley, West Virginia, and was pronounced dead upon arrival at 6:30 p.m, by a physician.
Investigation of the Accident
The Mine Safety and Health Administration (MSHA) was notified of the accident by Jimmy Williams, mine foreman, at 5:15 p.m., Tuesday, October 24, 2000. MSHA personnel and representatives of the West Virginia Office of Miners' Health, Safety and Training jointly conducted the investigation. A 103(k) order was issued to ensure the safety of all persons until completion of the investigation.
Photographs, sketches, audio/video recordings, and an engineering survey of the area of the accident were made. Interviews were conducted of persons considered to have knowledge of the facts surrounding the accident. The on-site portion of the investigation was completed and the 103(k) order terminated on November 8, 2000.
Discussion
Physical Factors
1. The 001 Section was a five-entry development section approximately 1,250 feet underground.
2. The mining height in the No. 3 to No. 4 crosscut was 72 inches. Mining height varied from 48 inches to 72 inches across the working section.
3. Rolling and steeply-pitching conditions were present throughout the mine.
4. The mine floor in the area of the accident scene was damp and the mobile-bridge conveyors had difficulty tramming up the steep grades.
5. The mobile-bridge conveyor (MBC) system was a Long-Airdox Model MBC 36, MSHA Approval No. 2G-3025A-5. The No. 3 bridge was Serial No. 53-1040. There were four MBC units in this system. The MBC was not mechanically or electrically connected to the continuous miner.
6. During the testing of the MBC system, no violations were observed on the No. 3 bridge. However, the No. 2 bridge panic bar stop switch was found to be out of adjustment where the panic switch would de-energize the MBC system but not latch out the restart circuit. The system was designed to require the operator who engages the panic bar to reset the starting circuit prior to re-energization.
7. Subsequent testing of the panic bar switch at the mine site and at the Long-Airdox facility at Pulaski, Virginia, revealed a potentially hazardous condition. In models manufactured prior to 1995, an Allen Bradley switch (catalog number 800T-XA) was used for the panic bar stop switch. This switch will allow the machine to be de-energize by lightly striking the panic bar but requires a deeper depression of the panic bar to activate the relay which, in turn, requires resetting the panic bar release switch. In models manufactured after 1995, an Allen-Bradley switch (catalog number 800T-XA1) was used for the panic bar stop switch. This switch has a set of normally-closed late-break, normally-open early-make contacts which allow the machine to be de-energize and the latching relay actuated simultaneously when the panic bar is struck. However, testing of these switches revealed that it is still possible to de-energize the machine and not activate the latching relay. The No. 3 MBC used the 800T-XA switch.
8. The victim had seven years experience as an underground coal miner and over three years experience operating this mobile-bridge conveyor system at another mine belonging to this company prior to moving to the Still Run No. 4 mine.
9. According to statements given during this investigation, the victim had trained other mobile-bridge operators and had often instructed the other operators to use the panic bar stop before getting off the equipment.
10. A buzzer system was used to communicate between the four units on the mobile-bridge system being operated at the time of the accident. A voice communication system was available as an optional accessory.
11. Arm-rest switches or gates were not used to keep the operators within the confines of the operator's deck while the equipment was energized. These switches or gates were not required; however, the gates were available from the equipment manufacturer as optional accessories. Arm-rest switches have since been added to the equipment approval that will de-energize and lock out all MBC units when any operator leaves the confines of the operator's compartment.
Conclusion
The evidence indicated that the most likely cause was that the victim exited the operator's compartment when the No. 4 bridge operator stopped to hook up the water line from the continuous miner, and the victim was crushed as the No. 4 bridge pulled forward to go under the continuous miner. This action caused the No. 3 bridge to skew toward the rib. This is due to the position of the mobile-bridge conveyor units relative to each other and the ease with which this possibility was recreated during the investigation.
Enforcement Actions
Issued to: Century Energy Corp.
1. A 103(k) order, No. 7179454, was issued to ensure the safety of the miners until the investigation could be completed.
2. A 314(b) safeguard, No. 7188696, was issued stating that during a fatal accident investigation it was revealed that communication between the operators of the Long-Airdox Model MBC-36, full dimension conveyor system, MSHA approval No. 2G-3825A-5, was not adequate. A buzzer system was provided but was not always used to indicate intended movement. The conveyor system operators were not always aware of the intended movement of the conveyor system. MSHA Program Information Bulletin No. P96-18 dated October 18, 1996 recommends that an adequate means of two-way communication be maintained between the conveyor system operators. This is a notice to provide safeguards that will require a two-way voice communication system be provided and used at this mine on all full dimension conveyor systems.
3. A 314(b) safeguard, No. 7188697, was issued stating that it has been determined during this fatal accident investigation that the mobile bridge operators on the 001-1 MMU were not staying within the confines of the operators compartment while the MBC system was energized. This is a notice to provide safeguards which will require the MBC operators to remain in the operator's compartment at all times when the system is energized and that emergency stop switches with interlocks be provided for each operator's compartment that would de-energize the entire MBC system when the operator/operators leave the confines of the operator's compartment. Approved technology is available for the Long-Airdox Model MBC-36 full dimension conveyor system, MSHA approval No. 2G-3825A-5, being used at this mine that would provide this protection.
Related Fatal Alert Bulletin:
FAB00C31
Appendix
The following persons were interviewed, provided information, and/or were present during the investigation.
Century Energy Corp.
Kenny Bowles ............... Superintendent
Jimmy Williams ............... Mine Foreman
Charles Halsey* ............... Section Foreman
Michael L. Toler* ............... No. 4 Bridge Operator/Evening Shift
Willis Monk* ............... No. 2 Bridge Operator/Evening Shift
Thomas Grubb* ............... No. 1 Bridge Operator/Evening Shift
Matthew J. Bailey* ............... Roof Bolter Operator (EMT)
Jimmy M. Lusk* ............... Continuous Miner Operator
Timothy J. Atwood* ............... Roof Bolter Operator
Kenneth C. Lamb* ............... Scoop Operator
Mark Heath ............... Attorney-At-Law, Heenan, Althen, & Roles
Jackie Allen* ............... No. 3 Bridge Operator/Day Shift
Triangle Safety Services, Inc.
Don Cook ............... Safety Trainer
WV Office of Miners' Health, Safety and Training
Fred B. Stinson ............... Inspector-at-Large
Terry Farley ............... Health and Safety Administrator
Donald L. Dickerson ............... Assistant Inspector-at-Large
Bob Thornsbury ............... Electrical Inspector
Steve Womack ............... District Mine Inspector
Mine Safety and Health Administration
William Uhl, Jr. ............... Coal Mine Inspector/Accident Investigator*Persons Interviewed
Mike Kalich ............... Coal Mine Inspector (Electrical)/Accident Investigator
Preston White ............... EFS Specialist
Bobby Butcher ............... Coal Mine Inspector (Roof Control)
Ted Tilley ............... Coal Mine Inspector