UNITED STATES
DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION

District 4

ACCIDENT INVESTIGATION REPORT
FATAL ELECTRICAL ACCIDENT
Freedom Mine (ID No. 46-07699)
Copperas Coal Corporation
Enon, Nicholas County, West Virginia

July 26, 1996

by

Ernie Ross Jr.

Coal Mine Safety and Health Inspector

Roy W. Milam
Electrical Engineer


Originating Office - Mine Safety and Health Administration
100 Bluestone Road, Mount Hope, West Virginia 25880
Ernest C. Teaster, Jr., District Manager

OVERVIEW

Abstract

A fatal electrical accident occurred on Wednesday, July 26, 1995, when William E. Barr, electrician, sustained a fatal electrical shock while performing electrical work on an energized belt power center.

The victim and James R. Robinson, chief electrician, were in the process of connecting a high-voltage power cable, from the newly installed section power center to the feed-through circuit of the No. 6 belt power center, to supply 4160 volt a.c. power to the section power center. Due to the emergency stop switch at the No. 6 belt power center not being connected in the high-voltage ground check circuit, Robinson and Barr discussed a plan to travel to the No. 5 belt power center and push that emergency stop switch to deenergize the high-voltage circuit. Robinson called John Cox, surface man, and instructed him to ascertain if the high-voltage circuit breaker in the substation had tripped and, if not, to trip it. Robinson instructed Barr to wait for him at the No. 6 belt power center and they separated. When Robinson arrived at the No. 6 belt power center, while en route to the No. 5 belt power center, he found Barr lying on the mine floor on his back beside the power center. The top metal cover of the power center had been slid back exposing the input end of the power center. There were no lid switches incorporated into the high-voltage ground check circuit.

The accident occurred at 7:00 p.m., 12 hours after the start of the shift.

Background

The Freedom mine is located at Enon, Nicholas County, West Virginia. The operation of the mine was assumed from Shamrock Coal Sales, Inc., by Copperas Coal Corporation on July 18, 1995, and was recorded in nonproducing status since July 17, 1995. The principal officers of Copperas Coal Corporation are Barry W. Elliott, President, and Gary D. Spurlock, Secretary/Treasurer.

Employment is provided for 14 employees, 11 of whom work underground on two shifts per day. Mine employees of the previous operator remain the same. The mine has not produced coal since June 30, 1995. Conventional mining equipment will be utilized when production begins.

Coal will be transported from the face by S & S scoops. Coal will be transported from the section to the surface via seven belt conveyors. The mine has four drift openings into the Peerless coalbed. The miners enter the mine via the No. 3 track entry portal and are transported by rail mounted, battery-powered personnel carriers to their assigned work areas.

The immediate mine roof is comprised of sandy shale and is supported with 4-foot resin-grouted roof bolts.

Ventilation is induced into the mine by a 54-inch Industrial Welding Axidyne fan, operated blowing and producing about 100,000 cubic feet of air a minute. The Peerless coalbed is above the water table. The mine does not liberate a measurable amount of methane.

DESCRIPTION OF THE ACCIDENT

On Wednesday, July 26, 1995, the day-shift crew began their shift at 7:00 a.m., under the supervision of Wesley Ayers, section foreman, and James R. Robinson, chief electrician. Robinson and William E. Barr, electrician, traveled underground with the section crew and began working on the section power center that was located about nine crosscuts outby the (001 MMU) section, while the section crew was doing section preparation work. This power center had recently been transported underground to replace the power center removed by the previous owner on July 3, 1995.

About 8:30 a.m., Robinson received a call informing him that electrical inspectors from the Mine Safety and Health Administration had arrived and requested his assistance in testing the surface high-voltage substation.

Robinson and Barr traveled to the surface. Robinson assisted in the inspection and testing of the substation. Barr traveled back underground and continued to work on the section power center. Mechanical and frame-structure work had to be done to the power center after it had been transported underground. Barr was assisted by Jerry Johnston, cutting-machine operator.

Primary injection testing of the high-voltage circuit breaker revealed all protective devices to be working properly. After the testing and inspection of the substation was completed, the electrical inspectors left the mine site. Robinson left the surface about 12:00 p.m. and traveled back underground on a rail- mounted personnel carrier to rejoin Barr at the section power center. Robinson stated that he stopped along the track to start dewatering pumps.

At approximately 12:30 p.m., Robinson arrived at the section power center location and continued to work on the power center with Barr. Johnston then proceeded to perform other duties.

Robinson and Barr decided to work the remainder of the evening shift to finish the power connection from the section power center to the No. 6 belt power center. Section equipment electrical circuits were to be checked out after the high-voltage cable had been entered into the No. 6 belt power center, according to Robinson.

About 6:45 p.m., Robinson and Barr used the battery-powered scoop to travel about 600 feet in the No. 2 entry to where the mantrip was left for them by the day-shift crew, which had left the mine at about 3:30 p.m. The tools and lunch buckets were transferred to the mantrip from the scoop. Robinson and Barr then used the scoop to travel to the battery charging station, about three crosscuts outby.

After arrival at the battery charging station, Robinson and Barr discussed how the No. 6 belt power center was to be deenergized. Robinson stated that Barr had indicated the emergency stop switch on the No. 6 belt power center was not going to operate. Robinson and Barr made a decision to travel to the No. 5 belt power center, approximately 1,000 feet outby, and push the emergency stop switch to deenergize the incoming high-voltage power.

Robinson called John Cox, surface man, on the battery charging station mine phone. Cox was instructed to travel to the surface substation and observe the high-voltage circuit breaker indicators to determine if the power was off underground. If the power was not off, Cox was instructed to turn it off. Cox was not a qualified electrician.

Robinson stated that he then told Barr to wait on him at the No. 6 belt power center while he went to get the rail-mounted mantrip. Robinson then crawled inby about three crosscuts to the rail- mounted personnel carrier. Barr crawled through the personnel door at the battery charging station and on to the No. 6 belt power center, a distance of approximately 60 feet.

Robinson boarded the rail-mounted mantrip and traveled outby about six crosscuts to the No. 6 belt power center while en route to the No. 5 belt power center. Robinson stated that upon his arrival at the No. 6 belt power center, he observed Barr lying on the mine floor on his back beside the power center. The top metal cover of the power center had been slid back and the power center was silent.

Robinson stated that he called out to Barr but did not get a response. He then went over to Barr and checked for vital signs. No pulse or respiration was detected. Cardiopulmonary resuscitation (CPR) was started and continued for about 5 minutes.

Robinson then traveled to the battery charging station and used the phone to call Cox on the surface. Cox was instructed to get the power turned off underground. Cox informed Robinson that he had not been able to find the keys to the substation. Robinson told Cox that he had the keys in his pocket and told Cox to do whatever was necessary to get the power turned off.

Cox then ran to the substation and made an attempt to climb the fence. He climbed up the gate and was squeezing between the gate structure and a strand of barbed wire when he saw an electrical arc or flash near the high-voltage power lines. Cox fell to the ground inside the substation. He heard a thumping sound and immediately climbed back over the gate.

Cox stated that he then traveled back to the mine office and called Robinson on the mine phone. He informed Robinson of what he had observed at the substation. Robinson instructed Cox to call Mike Morales, mine foreman, and to call an ambulance. He informed Cox that Barr was hurt.

Cox stated that he tried to call 911 on the mine office phone but the lines were dead. He informed Robinson that it would be a while because the phone was not working.

Cox and Mark Grose, surface man, then drove from the mine site to the Naomi Trucking garage, about 1.4 miles from the mine office. An ambulance was called but would be delayed due to dropping off another patient. According to Jan-Care Ambulance Service's dispatcher log, an ambulance was dispatched at 7:15 p.m. and arrived at the mine site at 8:18 p.m. Cox asked a worker to call Morales while Grose waited outside on the road to flag the ambulance.

Cox, after having some problems with his truck, drove back to the mine office. He called Robinson underground and informed him that an ambulance was on its way.

Robinson stated that he was traveling between the mine phone and the victim, and upon returning to Barr again, he pulled him toward the track to wait for help to arrive. CPR was continued, but no response was detected.

Mike Morales arrived at the mine about 8:20 p.m. and was met by Chris Kilburn, paramedic for Jan-Care Ambulance Service. Kilburn requested permission to travel underground with Morales. They immediately left the surface on a rail-mounted personnel carrier and traveled to the No. 6 belt power center. Upon arrival at approximately 8:35 p.m., Kilburn checked for vital signs and found none. A heart monitor and defibrillator were used, but no vital signs were detected.

Kilburn asked Morales if CPR could be administered while traveling to the surface. Morales stated that due to the low mine clearance, it would not be possible.

Barr was placed on a back board and transported to the surface on a rail-mounted personnel carrier. He was then taken by Jan-Care Ambulance to the Summersville Memorial Hospital where he was pronounced dead by Dr. Bruce Greenburg at 9:53 p.m.

INVESTIGATION OF THE ACCIDENT

The Mine Safety and Health Administration (MSHA) was notified of the accident by Dale McClung, safety director, Peerless Eagle Coal Company, at 9:18 p.m., July 26, 1995. Johnnie Tyler, Coal Mine Safety and Health Inspector, received the call. Ronald O. Dunbar, Assistant District Manager of MSHA, was notified of the accident by Tyler at 9:47 p.m., July 26, 1995.

A preliminary investigation began at 2:00 a.m., July 27, 1995, by representatives of MSHA and the West Virginia Office of Miners' Health, Safety and Training.

Management officials and employees present at the mine site gave statements concerning the accident. The physical accident site could not be visited until July 28, 1995, due to water accumulations in the track entry between the surface and accident site. Persons known to have information concerning the accident were interviewed on July 28, 1995, in the MSHA Summersville Field office conference room.

DISCUSSION

Training

The records indicated that Barr had received newly employed experienced miner training, as required by 30 CFR Part 48, from Copperas Coal Corporation on July 20, 1995. Barr also received electrical retraining on October 19, 1994, and was a qualified electrician. Barr had been employed at this mine for approximately 5 years.

Examinations

A review of the written reports for the on-shift and preshift examinations indicates that the required examinations were being performed. The weekly examination of all outby electrical equipment had not yet been completed by this operator.

Physical Factors

1. Three-phase electrical power for the mine, energized at a voltage of 4160 volts a.c., was purchased from Peerless Eagle Coal Company. The power was transmitted on overhead transmission lines to the mine substation where a 2000 kva, three-phase, isolation transformer was used to provide a resistance grounded, 4160 volt a.c. wye-connected secondary for underground power distribution.
   
   
2. The underground high-voltage power was transmitted on various lengths of high-voltage cables ranging in size from No. 2/0 AWG, Type MP-GC, 15 kv insulation to 4/O AWG, Type MP-GC, 8 kv insulation. Electrical protection of the 4160 volt a.c. distribution circuit was provided using a Westinghouse, Type ES, recloser rated for 800 amperes of continuous current flow, and protective relaying using three Westinghouse, Type CO-9, overcurrent relays and bushing-type current transformers with a ratio of 200:5. Overload protection was set to activate at 200 amperes of current flow, and short-circuit protection was set at 600 amperes of current flow. Grounded phase protection was provided using a Westinghouse, Type CO-11, over-current relay and a bar-type current transformer with a ratio of 25:5.

   The grounded phase relay was set to activate at 2.5 amperes of current flow. The high-voltage circuit was grounded through a 96-ohm-rated grounding resistor. Testing conducted during the investigation revealed that all protective devices incorporated as part of the high-voltage circuit breaker operated properly. The grounding resistor was found intact, measuring 97.5 ohms of resistance.
   
   

3. When the accident investigation team arrived at the substation, instantaneous target flags were visible on two of the three phase over-current relays and also the time target flag was showing on the grounded phase relay. The high- voltage circuit breaker was in the "open" position and no current flow was being indicated on the ground check circuit ammeter. When the investigation team attempted to close the high-voltage circuit breaker for testing, it would not close until the ground check conductor and the grounding conductor were shorted together. The visible target flags indicated that the high-voltage circuit breaker had opened upon the occurrence of a double phase-to-ground fault. The ground check conductor or the high-voltage grounding conductor was disconnected or open somewhere in the circuit.
   
   
4. The underground high-voltage distribution circuit extended from the substation through five sets of open-type disconnects, one line splitter, and two of the five belt power centers to the accident site at the No. 6 belt power center. The ground check conductor had been isolated through each piece of equipment, and the grounding conductor had been attached to each piece of equipment comprising a series circuit.
   
   
5. When the investigation team arrived at the mine on the morning of July 27, 1995, they were notified that the track entry was flooded between the mine portal and the accident site. Therefore, primary injection testing of the high-voltage circuit breaker was conducted, and arrangements were made to energize the high-voltage circuit to the open-type disconnects located at the No. 2 belt power center. This enabled dewatering pumps to pump the water outside, making the track passable on July 28, 1995.
   
   
6. When the investigation team arrived at the accident scene, the following conditions were observed on the No. 6 belt power center:
   
   
   1. The top cover of the No. 6 belt power center had been pushed back 25-1/2 inches, exposing the high-voltage input end of the power center.
      
      
   2. The high-voltage circuit ground check conductor was hanging in the air inside the power center, not connected to the frame.
      
      
   3. There were strands of broken wire extending from under a bolt and nut attached to the frame of the power center which were the same size and type as those used as the ground check conductor, indicating the connection had been broken recently.
      
      
   4. The bolt and nut listed in "c." were the same height as the top of three fuses and fuse holders providing over- current protection for the primary of the 150 kva three- phase transformer. The bolt and nut were separated from one fuse holder by a distance of 8 inches. Also, each of the three fuse holders were separated by 8 inches.
      
      
   5. There was visible evidence of electrical arcing on two of the fuses and fuse-holders. This evidence was present on the fuse nearest the bolt and nut listed in "c." and the center fuse.
      
      
   6. The blade-type disconnects inside the power center were in the "closed" position.
      
      
   7. The emergency stop switch mounted on the frame of the power center was inoperative because it was not connected in the high-voltage ground check circuit. The investigators found the switch in the pulled or "closed" position.
   
   
7. There was no nameplate on the No. 6 belt power center. The 150 kva, three-phase transformer was connected with a delta primary and a wye secondary, 480 volt a.c., which was grounded through a suitable grounding resistor. The output circuits provided power to the No. 6 belt drive motor and the battery charging station, and the third circuit did not have a load attached. It could not be determined who the manufacturer of the power center was nor the date of manufacture.
   
   
8. Resistance readings taken with a Dupont Blaster's volt-ohm- meter, revealed that the center fuse had opened. The fuses were a 65T fuse link closest to the bolt and nut listed in "c.", a 60A fuse in the center fuse holder, and a 65A fuse in the third fuse holder.
   
   
9. Resistance measurements taken with a Dupont Blaster's volt- ohm-meter revealed there were no grounded phases in the power center, the input high-voltage cable, or the high-voltage cable going to the section.
   
   
10. Testing conducted during the investigation, using a Dupont Blaster's volt-ohm-meter, revealed that the normally closed emergency stop switch worked properly, except it was not connected into the ground check circuit.
    
    
11. Testing of the high-voltage monitor circuit revealed that the high-voltage circuit breaker opened to deenergize the circuit each time the connection of the ground check conductor and the No. 6 belt power center frame was broken.
    
    
12. The No. 6 belt power center was not equipped with any whisker- type lid switches connected into the high-voltage ground check circuit.
    
    
13. Each connection point and each disconnect in and around the mine substation was visually examined during the investigation using a hydraulic-lift bucket truck. The center solid disconnect on the line side of the meter point showed evidence of electrical arcing, but it could not be determined if this arcing was recent or old.
    
    
14. Wesley Ayers, section foreman, stated that on Friday, June 30, 1995, during the last production shift for the previous mine owner, he asked Barr to disconnect the high-voltage cable extending from the No. 6 belt power center to the section power center. Ayers also stated that on Monday, July 3, 1995, when he and a co-worker arrived at the No. 6 belt power center, the cable had been disconnected from the power center, so they continued to the section power center, cut the high- voltage cable using a hacksaw, and removed the section power center from the mine.
    
    
15. The commercial phone line serving the mine office had been severed during the evening of the accident by persons doing vegetation removal along the mine haul road.
    
    
16. Robinson stated that the normal procedure used when working on the high-voltage circuit was to push the emergency stop button on a power center to cause the high-voltage circuit breaker to open. Then the surface man would be called and instructed to visually check and see that the circuit breaker had opened. Then the ground check conductor would be disconnected inside the power center.
    
    
17. The investigation team found no tools at the accident site.

CONCLUSION

The accident and resultant fatality occurred when the victim attempted to disconnect the high-voltage circuit ground check conductor from the frame of the No. 6 belt power center and came into contact with two energized, 4160 volt a.c., fuses and fuse holders. Other contributing factors were:

1. Management's failure to disconnect, lock out, and tag the high-voltage disconnecting devices prior to work being performed.
   
   
2. Management's failure to deenergize and ground the high-voltage circuit prior to working on it.
   
   
3. The emergency stop switch on the No. 6 belt power center was not connected into the high-voltage ground check circuit.

ENFORCEMENT ACTIONS

1. A 103(k) Order No. 3338394 was issued to assure the safety of all miners until the investigation of the accident was completed.
   
   
2. A 107(a) Imminent Danger Order No. 3964488 was issued in conjunction with three 104(a) Citations for the following conditions:
   
   
   1. A 104(a) Citation No. 3964489 (30 CFR 75.509) was issued because the victim was working on an energized, 4160 volt a.c. circuit when he was electrocuted.
      
      
   2. A 104(a) Citation No. 3964490 (30 CFR 75.511) was issued because the disconnecting devices for the high-voltage circuit had not been disconnected, locked out, and tagged prior to performing work on the circuit.
      
      
   3. A 104(a) Citation No. 3964491 (30 CFR 75.705) was issued because the high-voltage circuit had not been deenergized and grounded prior to work being performed on the circuit.
   
   
3. A 104(a) Citation No. 3964492 (30 CFR 75.1725(a)) was issued because the emergency stop switch mounted on the No. 6 belt power center was not connected into the high-voltage ground check circuit.

Respectfully submitted by:

Ernie Ross, Jr.
Coal Mine Safety and
Health Inspector

Roy W. Milam Electrical Engineer

Approved by:

Ronald O. Dunbar
Assistant District Manager

Earnest C. Teaster, Jr.
District Manager

Related Fatal Alert Bulletin:
[FAB95C22]