DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Coal Mine Safety and Health
Report of Investigation
(Underground Coal Mine)
Fatal Electrical Accident
July 20, 2001
# 77 Mine
Blue Diamond Coal Co.
Delphia, Perry County, Kentucky
I.D. No.: 15-09636
Accident Investigator
Buford Conley
Coal Mine Safety & Health Inspector
Originating Office:
Mine Safety and Health Administration
District 7
3837 S. U.S. Hwy. 25E, Barbourville, Kentucky 40906
Joseph W. Pavlovich, District Manager
Report Release Date: December 6, 2001
OVERVIEW
At approximately 2:00 a.m. on Friday, July 20, 2001, a fatal electrical accident occurred at the # 9 belt drive located on the 010 working section of the Blue Diamond Coal Co., # 77 Mine near Delphia, Perry County , Kentucky.
Gary Caudill, Jr., a 26 year old electrician with 5 years total mining experience, of which 1 year and 2 months of this experience was as an electrician, suffered fatal injuries when he came in contact with energized components inside the starting box serving the # 9 belt drive. He was attempting to remove the starting box from service when the accident occurred.
The accident occurred as a direct result of the victim coming into contact with energized electrical components. Work was performed on energized electrical equipment prior to the mine operator's ensuring that all electrical power sources to the equipment were properly locked and tagged out.
GENERAL INFORMATION
The # 77 mine located at Delphia in Perry County, Kentucky, is operated by Blue Diamond Coal Co., a subsidiary of James River Coal Company. The mine employs 70 persons underground and three persons on the surface. The mine consists of two shafts and a slope. Coal is transferred to the surface by a conveyor belt located in the slope entry. The mine produces coal two shifts per day, five days per week, from the Elkhorn # 3 Coal Seam, which averages 60" in thickness. Maintenance and support work are performed on the third shift.
The mine produces an average of 2500 tons of coal daily. Coal is transported from the face utilizing Long-Airdox Continuous Haulage System(s). Currently the mine consists of two working sections. The mineral resources are owned by Kentucky River Coal Corporation. The surface is owned by Blue Diamond Coal Co.
The principal officers of the operation are as follows:
Charles Bearse .......... PresidentThe last Mine Safety and Health Administration (MSHA) regular Safety and Health Inspection (AAA) was completed on June 07, 2001.
John Boylen .......... Operation Manager
Andy Fields .......... Safety Director
Hershel Asher .......... Superintendent
Willie Collins .......... Chief Electrician
Cheyene Toy Coots .......... 3rd Shift Chief Electrician
DESCRIPTION OF ACCIDENT
The 3rd shift began as scheduled at 10:30 p.m. on July 19, 2001. Sam Combs, foreman of the 010 working section (MMU), and his crew; Tommy Rice, Mack T. Halcomb, Scott Fields, and George Woods; began work by traveling from the surface to the 010 Section sub-main's # 9 belt drive location. The second shift crew consisting of; Robert Begley, Alger Bowen, Jeff Begley, Walter Napier, Chester Adams, Scott Fields, Randall Eldridge, Bill Smith, and Shane Baker; was completing mining operations on the 010 MMU panel. The second shift crew was scheduled to stay over on the next shift and begin moving equipment back down the # 4 intake entry to the # 9 belt drive location. Sam Combs and his 3rd shift crew were to install belt structure for the newly relocated 010 MMU. Cheyenne Toy Coots, 3rd shift Chief Electrician, and Gary Caudill, Jr., Electrician, (victim) were scheduled to remove the # 9 belt drive from service in preparation for the new set-up (010 MMU sub-mains). The two electricians, Coots and Caudill, had gotten a late start and did not arrive at their work location underground until 12:00 p.m. According to Coots, after arriving at the scheduled work location (010 MMU, # 9 belt drive), he traveled through the mandoor at the # 9 belt drive and checked the area. Coots met Caudill as he traveled back through the mandoor to the 300 KVA power center to disconnect the power for the # 9 belt box. When he arrived at the 300 KVA Power Center, the disconnecting device (cat-head) for the # 9 belt box had already been pulled and was lying on the mine floor, but was not locked and tagged out. Coots stated that he placed his lock on the belt box cat-head and traveled back around the pillar block to the # 9 belt drive location.
Caudill was working at the belt box disconnecting the # 9 belt drive motor leads inside. Coots helped Caudill loosen the entrance gland on the belt box and pulled the 2/0 cable from the belt box that served the # 9 belt drive.
Caudill continued working at the belt box location while Coots began to remove guards (steel screens) from the # 9 belt drive (belt box side). Two guards were removed and placed on the left coal rib just inby the belt box with the assistance of Caudill.
Coots next traveled to the other side of the # 9 belt drive to begin removing guards when he heard Caudill call out and say that APower was on the belt box". Coots stated that he told Caudill that there could not be any APower@ on the belt box because the cat head was pulled, locked, and tagged out. According to Coots, Caudill called out a second time. Coots walked just inby the guards on the off side of the # 9 belt drive and saw Caudill lying on the mine floor with his shirt caught on the inside door latch of the belt box (monitor side). Coots stated that he yelled to the victim several times but Caudill gave no response.
Coots then traveled in between the # 9 belt conveyor from the off side of the drive to the belt box location and tried to pull the victim back by his suspenders (which were mounted to his mining belt) but felt the effects of electrical current. Coots then tried to push the victim away from the energized belt box with his right foot and likewise felt electrical current. Coots stated that he then managed to free the victim by placing his foot in the abdomen area of Caudill and rolling him onto his back.
At approximately 2:15 a.m., Coots traveled over to the mandoor located at the # 9 belt drive and called to Sam Combs, foreman, located approximately 100' away, stating that he had "a man down" and needed help. Combs and his crew traveled over to the #9 belt drive location and reportedly saw the victim lying on the mine floor on his back. According to Combs, he also felt electrical current on the belt box while he tried to reach the phone located inside the right hand compartment of the box. Combs told George Woods and Gary Hubbard to travel to the 010 MMU face area and inform Robert Begley, foreman, what had happened. The 010 MMU face area was notified at 2:20 a.m. and the entire crew began to travel outby to the #9 belt drive location to offer assistance.
According to information gathered at the interviews, Robert Begley, Scott Fields, Jeff Begley, and Tommy Rice assisted in performing cardio-pulmonary resuscitation on the victim. There was no response from the victim.
Combs instructed Chester Adams, Lo-Lo man, to travel outby to the end of the 010 MMU track where a phone was located and to notify the surface. Edgar Sloan, surface employee, was notified of the accident and summoned an ambulance at approximately 2:45 a.m.
Combs stated that the victim was transported on a four wheel personnel carrier to the 010 MMU 'end of track', arriving at 3:38 a.m. The victim was placed onto a diesel track-mounted personnel carrier and transported to the elevator location at the shaft bottom. He was then transported to the surface, where he arrived at 4:02 a.m. With no vital signs, the victim was pronounced dead at the mine by Deputy Coroner Clayton Brown and was subsequently transported by the Perry County Ambulance Service to Frankfort, Kentucky for autopsy by the state medical examiner's office.
INVESTIGATION OF THE ACCIDENT
At approximately 2:50 a.m., Robert Rhea, MSHA Supervisor, Harlan, Kentucky Field Office, was notified of the accident. Rhea proceeded to the mine, accompanied by coal mine inspectors Lester Cox and Darlas Day. A 103-K-Order was issued to ensure the safety of the miners until an investigation could be conducted. Preliminary information was gathered and initial interviews were conducted of all persons who had knowledge of the accident. An Accident Investigation Team consisting of Buford Conley, Coal Mine Safety and Health (CMS&H) Inspector, Jim Oakley, Supervisory CMS&H inspector, Pat Stanfield, CMS&H Specialist, and Jim Langley, Supervisory CMS&H Inspector, was subsequently dispatched to the mine to conduct the investigation. The formal investigation into the fatal accident began at approximately 8:30 a.m. on July 20, 2001. The investigation was conducted jointly by a team from the Kentucky Department of Mines and Minerals (KDMM) and MSHA. Relevant measurements and photographs were taken to be included in the report and were shared by members of both teams. Joint formal interviews were held on July 24, 2001 at the Hazard office of KDMM and, later, at the mine operator's offices on July 25, 2001. None of those persons interviewed requested that their statements be kept confidential by MSHA.
Thomas Barkand, electrical engineer from MSHA's Pittsburgh Safety and Health Technology Center (PSHTC), provided assistance in evaluating the electrical installation on the 010 MMU and at the accident location.
The on-site portion of the investigation was completed on July 25, 2001.
DISCUSSION
The investigation began with an examination of the electrical equipment. The electrical power was deenergized to the 010 MMU's 300 KVA power center located at the # 9 belt drive. The cat head which supplied power to the # 9 belt drive was locked and tagged out. The ground fault system was examined and found to be adequate at the power center. The cat head for a 20 HP water pressure (booster) pump was found lying on the mine floor and was further found by MSHA not to be locked and tagged out as required by regulation.
A 110 volt, 1/3 HP sump pump was found plugged into the 300 KVA Power center. The sump pump was located just outby the belt drive mandoor and was energized but not running when examined. This pump was received by MSHA and taken to the Technical Support Center for further evaluation. The wiring for the sump pump also proved to be adequate. The ground wire was found to be electrically continuous from the ground pin at the plug to the frame of the sump pump. The power cord and motor insulation were also tested. The insulation resistance was found to be 100 M ohms between the frame ground and each of the power conductors. The insulation was tested by energizing the circuit to 500 volts direct current (VDC) (using the insulation tester's 500 V scale) with the sump pump float switch in the closed position. The sump pump motor was operational, and the float switch was functional. The pump is "ON" when the float switch lever arm is in the "UP" position. The pump is "OFF" when the float switch lever arm is in the "DOWN" position. Although the pump=s wiring installation was found to be adequate, connectors were not utilized for splicing of the cable.
The # 9 belt drive motor leads and all control cables were found by MSHA to be disconnected. The belt box circuit breaker was found to be in the 'closed' position. The resistance of the power leads from the feed-through disconnect to the starting box of the # 9 belt drive was measured at 972 ohms. The resistance of the motor leads that were disconnected (and lying in water) to the starting box was measured at 1.4 ohms.
Resistance was checked from the mine phone to the belt starting box. The white phone wire was found to have a resistance of 0.5 ohms. 1.45 ohms were measured between the white phone wire and the frame of the phone. No voltage was found in this circuit.
The 20 HP booster pump located at the accident site was examined. Initially, the booster pump had been wired into the belt box so that the booster pump would automatically be energized when the # 9 conveyor belt started. The switch for the line starter to the booster pump was found by MSHA to have been by-passed. The disconnect for the booster pump was found in the 'closed' position. The 16/3 control cable for the pump which ran to the belt starting box had been severed at the pump location. The 16/3 control cable was not connected inside the belt box at the time of the investigation (the electrical connectors were still on the ends of the cable). Examination revealed that the 16/3 cable had been physically pulled loose from the interlock inside the belt box.
The electrical installations at the accident site were examined completely for possible stray currents and none were found. Ground fault protection and the condition of power cables was found to be adequate on all equipment examined.
PHYSICAL FACTORS INVOLVED
The following physical factors were determined to be relevant to the occurrence of the accident.
1. The accident occurred underground at the # 9 belt drive (section belt), on the 010 working section.
2. The # 9 belt starting box did not have serial numbers nor could the manufacturer's name or model be determined.
3. The # 9 belt conveyor drive is approximately 1,050 feet below the surface.
4. The area around the # 9 belt starting box was found to be wet.
5. Gloves were not being used by the victim at the time of the accident. Leather boots were being worn.
6. The nearest surface high voltage transmission line is approximately 4,000 feet west of the surface area directly above the # 9 belt conveyor drive. The surface overhead transmission line is rated at 12,470 volts (three phase).
7. A control cable had been connected from the 480 VAC booster pump starter contactor coil to an auxiliary N.O. (Normally Open) contact on the Vacuum Contactor in the starting box for the # 9 belt conveyor drive motor. The total length of the booster pump control cable was measured at approximately 118.5 feet, and was spliced together from two different types of cable. The longest section of the pump control cable, 115 feet, was 16 AWG, .3 conductor, 600 V, and was manufactured by Carol. The 3.5 feet section of cable on the booster pump end was manufactured by Coleman Cable. All three conductors (black, white, and green) maintained electrical continuity through the entire length of the cable. A 7 inch section of the Coleman cable was formed into a knot, and was found inside the 480 V booster pump contactor box. All three conductors of the 7 inch section were electrically continuous. At the time of the investigation, the cable knot was not found by MSHA to be wired into the booster pump contactor coil circuit.
8. The booster pump contactor was connected across two incoming power phase conductors at the top of the contactor (the left and right side phase terminals). This control configuration would cause the booster pump to run continuously as long as power was provided to the booster pump contactor box. The wire connecting the right phase incoming power conductor to the contactor coil contained an insulated (twisted wire) connector. The insulation on the individual wires within the uninsulated electrical splice corresponded to the wire insulation on the 7 inch knotted piece of Coleman cable found inside the booster pump contactor box.
9. No phase-to-ground electrical faults were found on the 480 VAC booster pump motor. Resistance measurements between the 480 VAC booster pump motor phase conductors and the motor frame indicated an open circuit.
10. The normally open auxiliary contact, mounted on the belt starter vacuum contactor, was dislodged from its normal operating position. The auxiliary contact was not damaged, but would not function as intended in this misaligned position.
11. The # 9 belt starting box normally had two power sources entering the box. The primary 480 volt circuit for the conveyor system and the 277 volt control circuit for the booster pump.
12. At the time of the investigation, all power cables entering the # 9 belt starting box either had been severed or removed.
13. All electrical equipment at this mine was checked for any possible source of stray electrical current. None was found.
14. The sump pump was manufactured by Zoeller Pump Co., Model M53-D, Part Number 53-0001, 0.3 HP, 9.7 Amp, 115 Vac, Single Phase, 60 Hz, thermally protected, with a manufacture date of May, 2000. The total length of the pump cable was measured at 122.5 feet. A 113.5 foot section of the pump cable was 16/3 cable manufactured by Coleman cable and was spliced into the pump's original 9 feet of 8/3 power cable. One electrical splice was located 2.5 feet away from the plug. The electrical splice connections were twisted bare wire, and individually insulated with electrical tape. Electrical tape was also wrapped around the bundle of three conductors at each cable splice location. It was determined by the accident investigation team that this pump was not a probable source of electrical current for the accident. A BK Precision, Model 307 electronic insulation tester was used to test electrical continuity on the electrical wiring.
ALTERATION OF THE ACCIDENT SCENE
Altering of the accident scene prior to the investigation prevented the accident investigation team from determining the exact source of power and circumstances leading up to the accident. The investigation revealed two possible sources of electrical current at the location of the accident. The first was the 480 volt power source for the belt starting box and the second was one phase of the 480 volt booster pump control circuit (277 volts). Examination of the 480 volt power source for the belt starting box and the statements obtained during interviews has led the accident investigation team to conclude that, although possible, this was not the probable source of current involved in the accident. Based upon the evaluation of the interviews and physical evidence at the accident scene, the accident investigation team has concluded that the probable source of current was the 277 volt booster pump control circuit.
Due to the alteration of the scene, the manner by which the victim came into contact with the source of current could not be determined. Three probable means of contact were identified; 1) direct contact with the auxiliary N.O. (Normally Open) contact on the vacuum contactor in the belt starting box, 2) contact with the exposed leads at the end of the control cable, and 3) the belt starting box frame becoming energized as a result of contact with the control cable leads.
CONCLUSION
The accident occurred as a direct result of the victim coming into contact with energized electrical components. Work was performed on energized electrical equipment prior to the mine operator's ensuring that all electrical power sources to the equipment were properly locked and tagged out.
ENFORCEMENT ACTIONS
1. 103(k) Order # 7529252 - A 103(k) order was issued to assure the safety of all persons in the coal mine until an investigation could be conducted.
2. 104(d)(1) Citation # 7476996 - Work was performed on electrical circuits and equipment without all power first being deenergized, while under the direct supervision of the chief electrician. The electrical circuit (277 volts) entering the # 9 belt starting box and supplying power to the 20 HP booster pump was not deenergized prior to work being performed on the energized circuit.
3. 104(d)(1) Order # 7476997 - The 010 MMU section's 20 HP booster pump located outby the # 9 belt drive was not grounded as required. A separate circuit originating from the booster pump starter had been installed to the # 9 belt box. The start/stop switch had been defeated (by-passed). This circuit permitted the pump to start when the # 9 belt started. Power was supplied to the circuit by the 16/3 pump cable conductor. The ground wire had been cut off at both ends where the cable left the pump starter and where the cable entered the belt box. With the # 9 belt box disconnect device unplugged, the # 9 belt box was still energized with 480 volts from the 20 HP booster pump and had no means of proper grounding.
4. 104(d)(1) Order # 7476998 - Mine management failed to insure that all electrical circuits and equipment were properly locked out and suitably tagged while electrical work was being performed. The electrical circuit serving the 20 HP booster pump was not locked out and suitably tagged while electrical work was being performed.
5. 104(d)(1) Order # 7476999 - Electrical equipment (20 HP booster pump and the # 9 belt drive's starting box) had not been properly examined and maintained to assure safe operating condition. An examination of this equipment revealed the following conditions : 1) A separate circuit originating from the booster pump's start box had been wired to the # 9 belt box; 2) The start/stop switch located on the booster pump had been defeated (by-passed), allowing the booster pump to start when the # 9 conveyor belt was started; 3) The ground wires were found to have been cut at the booster pump and the belt drive starting box; and 4) The 20 HP booster pump was not listed in the records of the examination of electrical equipment.
6. 104(a) Citation # 7477000 - The site of an accident that resulted in the death of a mine electrician on July 20, 2001, was found to have been altered prior to the completion of all investigations, and without MSHA approval. It was determined that the site was altered due to the following: 1) The disconnect device (cat-head) which supplied power to the 20 HP booster pump had been disconnected at the 300 KVA power center and was lying on the mine floor; 2) The 16/3 cable extending from the booster pump to the # 9 belt drive starting box had been cut at the pump start box location; and 3) The 16/3 cable extending from the booster pump to the # 9 belt drive starting box had been disconnected from the inter lock on the vacuum breaker and had been pulled completely out of the belt box. None of these conditions could have existed at the time of the fatal accident. Mine management failed to preserve and secure the accident site.
7. 104(d)(1) Order # 7478001 - The electrical circuit breaker supplying power to the 20 HP booster pump located outby the # 9 conveyor belt drive was not properly marked for identification. The subject electrical circuit breaker was identified and labeled as "pump", but was in fact supplying electrical power for two different devices; the pump and a separate circuit entering the # 9 belt starting box.
Related Fatal Alert Bulletin:
FAB00C11
APPENDIX A
LIST OF PERSONS PARTICIPATING IN THE INVESTIGATION
BLUE DIAMOND COAL CO., # 77 MINE
Charles Bearse .............. President, BDCCPERRY COUNTY AMBULANCE AUTHORITY
John Boylen .............. Operations Manager
Andy Fields .............. Safety Director
Hershel Asher .............. Superintendent
Willie Collins .............. Chief Electrician
Charles Ricketts .............. Attorney
Marco Rajkovich .............. Attorney
Danny Pratt .............. Crew MemberPERRY COUNTY KENTUCKY OFFICIALS
Leslie Hall .............. Crew Member
Clayton Brown .............. Deputy Perry County CoronerKENTUCKY DEPARTMENT OF MINES AND MINERALS
Tracy Stumbo .............. Chief Accident InvestigatorMINE SAFETY AND HEALTH ADMINISTRATION
Dave Johnson .............. Chief Electrical Inspector
Randy Campbell .............. Electrical Inspector
Johnny Green .............. Accident Investigator
Bobby Ashworth .............. Mine Inspector
John Pyles .............. Assistant District Manager
Jim Langley .............. Supervisory Coal Mine Inspector
Patrick Stanfield .............. Coal Mine Inspector, Electrical Specialist
Buford Conley .............. Coal Mine Inspector, Accident Investigator
James W. Oakley, Sr. .............. Supervisory Coal Mine Inspector, Electrical Specialist
Thomas Barkand .............. Engineer, Mine Electrical Systems Division, PSHTC
Greg Gluck .............. Education Field Services, Training Specialist
MaryBeth Bernui .............. Solicitors Office, U.S. Department of Labor
APPENDIX B
LIST OF PERSONS INTERVIEWED
Elgar Sloan .............. Surface Employee
Troy Combs .............. 2nd Shift Foreman
Shane Baker .............. Bolter Operator
Robert Begley .............. 2nd Shift Foreman
Bill Smith .............. Bolter Operator
Randall Eldridge .............. Mobile Bridge Operator
Jeff Begley .............. Electrician
Alger Bowen .............. Miner Operator
Chester Adams .............. Lo-Lo Man
Willie Collins .............. 1st Shift Chief Electrician
Bob Schell .............. 2nd Shift Chief Electrician
Cheyenne Toy Coots .............. 3rd Shift Chief Electrician
Sam Combs .............. 3rd Shift Foreman
George Woods .............. Roof Bolter Operator
Tommy Rice .............. Mechanic Welder
Gary Hubbard .............. Roof Bolter Operator
Mack Halcomb .............. Scoop Operator
Scott Fields .............. Mobile Bridge Operator