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DEPARTMENT OF LABOR MINE SAFETY AND HEALTH ADMINISTRATION Southeast District Metal and Nonmetal Mine Safety and Health Accident Investigation Report Underground Nonmetal Mine Fatal Electrical Accident Dravo Lime Company Black River Mine Butler, Pendleton County, Kentucky Mine I.D. 15-00062 July 11, 1997 By Larry R. Nichols Supervisory Mine Inspector Clarence F. Holiway Mine Safety and Health Inspector (Electrical) Originating Office Mine Safety and Health Administration 135 Gemini Circle, Suite 212 Birmingham Alabama 35209 Martin Rosta District Manager GENERAL INFORMATION John A. Miller, mine mechanic, age 42, was electrocuted at approximately 6:20 p.m. on July 11, 1997, when he contacted the metal wand of a high pressure washer that was energized with approximately 277 volts AC. The victim had 9 years, 3 months experience at this mine, with 9 of these years as a journeyman electrician and the last 3 months as a mine mechanic. Records indicated the victim had received annual refresher training in February, 1997, in accordance with 30 CFR, Part 48. David Feagan, employee relations manager for Dravo Lime Company, notified the Birmingham, Alabama, district office of the accident at 7:40 p.m., on July 11, 1997. An investigation was started the same day. The Black River Mine, an underground limestone operation, owned and operated by Dravo Lime Company, was located adjacent to State Highway 8, about 12 miles northeast of Butler, Pendleton County, Kentucky. The principal operating official was Mark Davis, vice president of operations, Black River Division. The mine normally worked two, 10 to 12 hour shifts per day, 7 days a week, and employed 145 persons. Mining method was room and pillar, with conventional drilling and blasting. Blasted material was loaded by front-end loaders into haulage trucks and transported to two underground primary crushers. Crushed material was conveyed to the surface by a series of conveyor belts to the mill surge pile. The last regular inspection of this operation was conducted May 19-22, 1997. PHYSICAL FACTORS INVOLVED The accident occurred in the underground equipment wash bay area which was 24 feet high, 35 feet wide, and 40 feet long. Equipment could access the area through several openings. Underground power was supplied from a 480 volt AC, 3 phase wye connected solid grounded system. The equipment involved in the accident was a three phase, 480 volt AC, Silverjet high pressure washer, Model No. XHWK, manufactured by Upstream Technology, Incorporated. The washer produced a water pressure of 2100 psi, with options of hot, cold or soap water dispensed through a braided hose and a metal wand. Power for the washer was supplied from a combination starter consisting of a 600 volt AC, 60 amp, 3 phase Westinghouse circuit breaker and a size one motor starter. The combination starter was equipped with a 4 conductor Hubbellock female plug. An electrical control panel mounted on the washer was equipped with a 6 foot, 4 conductor cable with a male Hubbellock plug. An older Silverjet high pressure washer in the wash bay area had components that were interchangeable with the washer involved in the accident. Neither of the pressure washers was working prior to the day of the accident. DESCRIPTION OF ACCIDENT John A. Miller, victim, reported to work on July 11, 1997, at 7:00 a.m., his regular starting time. Miller was instructed by his supervisor, Rick McElfresh, to repair one of the washers and if necessary, combine components from both to make one operable. Miller proceeded to the wash bay area and began working on the washer. The washer Miller chose to repair was the newer model. He worked on the pressure washer throughout the day, at times conversing with his supervisor and other employees about parts and repairs that were needed to complete his task. At approximately 2:00 p.m., Pam Hargett, laborer, went to the wash bay area with a forklift to remove the older washer. Miller cut the power cable off the old washer before it was moved. Gary Green, mine mechanic, arrived at the wash bay area at approximately 4:15 p.m., to clean the engine of a roof bolting machine. Miller had completed repairs enough to enable Green to use the washer; however, every time Green released the trigger on the hand-held wand that controlled the water flow, the heater for the hot water would shut off. In order to finish the job, Miller would operate the heater switch manually so they could complete cleaning the engine. Green left the area at approximately 4:50 p.m. and Miller continued to work on the washer. Sometime after Green left, Miller removed the power cable from the washer and replaced it with the longer one he had cut from the old washer. When he connected the cable into the control panel, the red and green wires were switched. The red power wire was connected to the equipment ground and the green ground wire was connected to the insulated connector block. Rick McElfresh, supervisor, passed by the wash bay area at approximately 6:15 p.m., and in passing, yelled to Miller and asked how he was doing. Miller informed him that he was about ready to try the washer. When the combination starter was energized, 277 volts were directed onto the washer frame and its metal parts. Moments later Miller picked up the hand-held wand and was electrocuted. At approximately 6:20 p.m., Chris Spencer, mine mechanic, went to the wash bay area and found Miller lying on the ground near the washer with the wand in his hand. He touched Miller and received a shock. Spencer ran to the shop calling for help. Lonnie Adams, electrician, immediately ran to the combination starter and de-energized the circuit. They checked Miller's vital signs but were unable to detect a pulse. CPR was began immediately, and continued as Miller was being transported to the surface where emergency personnel continued efforts to resuscitate him. He was transported by ambulance to St. Luke East, Hospital in Ft. Thomas, Kentucky where he was pronounced dead at 7:45 p.m. CONCLUSION The cause of the accident was the power cable being wired incorrectly and continuity of the grounding conductor not being checked after repairs were made. VIOLATIONS Order No. 4554730 Issued on July 12, 1997, under the provisions of Section 103(k): Citation No. 4355178 Issued July 15, 1997, under provisions of Section 104a of the Mine Act for violation of Standard 57.12028: /s/Larry R. Nichols Supervisory Mine Inspector /s/Clarence F. Holiway Mine Safety and Health Inspector, (Electrical) Approved by: Martin Rosta, District Manager Related Fatal Alert Bulletin:  [FAB97M37]
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