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DEPARTMENT OF LABOR MINE SAFETY AND HEALTH ADMINISTRATION Western District Metal and Nonmetal Mine Safety and Health Accident Investigation Report Underground Metal Mine Fatal Hoisting Accident Thyssen Mining Const. of Canada Contractor ID NEV at Turquoise Ridge Mine (Mine ID No. 26-02286) Getchell Gold Corp. Golconda, Humboldt County, Nevada May 26, 1997 by David A. Kerber Mine Safety and Health Inspector Gary L. Cook Mine Safety and Health Inspector Mine Safety and Health Administration Western District 2060 Peabody Rd.,Suite 610 Vacaville, California 95687 James M. Salois District Manager GENERAL INFORMATION Everette Thomas Howard, clam shell operator, age 54, was fatally injured at about 8:55 p.m., May 26, 1997, when he was struck by a shaft sinking bucket. Howard had about 28 years of mining experience, the past seven weeks as a clam shell operator at this operation. He had received training in accordance with 30 CFR Part 48. New task training was completed on April 18, 1997. Charles Pearson, safety director for Thyssen Mining Construction of Canada, notified MSHA on the day of the accident. An investigation was started the following day. The Turquoise Ridge mine, in the shaft sinking phase of its development, was owned by Getchell Gold Corporation. The mine was located near Golconda, Humboldt County, Nevada. Principal operating officials for the shaft sinking contractor were Andrew Fearn, area manager, Grant Coad, project engineer, and Quinn Olson, superintendent for shaft No. 1. The 114 employee operation normally worked three 8-hour shifts, seven days a week. Getchell Gold Corp. had one employee in the shaft, acting in an advisory capacity. The shaft sinking process was accomplished by drilling and blasting. Material was loaded into one of two six-cubic yard buckets, hoisted to the surface, and hauled away as waste. The last regular inspection of this operation was completed on May 14, 1997. Another inspection was conducted in conjunction with this investigation. PHYSICAL FACTORS INVOLVED The ventilation shaft, where the accident occurred, had been sunk to 1354 feet, with levels at the 400 and 900 foot marks. The concrete finished inside diameter of the shaft measured 20 feet. An Ingersoll Rand double drum hoist raised and lowered twin buckets in the shaft. The hoist had a suspended load capacity of 32,549 pounds. Each bucket weighed 3600 pounds and measured 85 inches in height and 62 inches in diameter. The buckets could be raised and lowered as counterweights, or clutched out and used separately. A four-deck Galloway was used in the shaft to provide work platforms for lowering concrete forms, pouring concrete, and storing equipment. It was raised and lowered by the surface hoist using four 1-1/2 inch diameter wire ropes. The wire ropes were also guides for the two sinking bucket crossheads. The Galloway measured 31 feet in height and 18 feet in diameter. The crossheads stopped at the top deck on devices called "chairs," and the shaft buckets were released to travel to the other levels of the Galloway stage or the bottom of the shaft. The second deck was used primarily as a storage and work deck and the third deck housed the electrical distribution station. The bottom deck was fitted with swing type doors, covering the bucket wells, that provided access to the shaft bottom. This deck was where most of the work was performed. The Galloway was prevented from swinging in the shaft by four wedges called "horse heads." At the time of the accident, the Galloway bottom deck was about five feet above the shaft bottom. The crossheads traveled with the buckets and controlled their lateral movement between the collar and Galloway. They were equipped with a guillotine, a device designed to release the bucket at the Galloway so it could continue through the structure to the shaft bottom. Modifications and prior damage had caused the crossheads to become twisted and bent, affecting the performance of the guillotines. There were signal controls from the collar to the bottom of the shaft. A top lander, using bell signals, controlled the loading and off-loading of personnel as well as the opening and closing of collar doors. The top lander would usually bell the initial signal to the levels or to the Galloway. Persons in the bucket could also signal the hoistman. Prior to reaching the Galloway, the hoistman would flash signal lights on the Galloway, alerting workers that the bucket was approaching. Company policy required that the bucket stay in the crosshead until a bell signal was given to the hoistman by a designated person on the Galloway. The bucket was then lowered to the Galloway where the guillotine would open and release it to travel further. The designated person on the Galloway controlled lowering through the structure. DESCRIPTION OF ACCIDENT On the day of the accident, Everette Howard reported for work at 3:00 p.m., his regular starting time. The crew finished the mucking cycle at approximately 7:30 p.m. and the clam shells were raised and the crew began to set the concrete curb ring on the bottom of the shaft. Chuck Martinez, clam shell operator, discovered that the Galloway and curb ring were not level and signaled the hoistman to raise the bucket to provide the crew room to work. The power failed while the crew was attempting to level the two components. Hank DiCamillo, the walking boss, sent Martinez to the 900 level to set the breaker and to call for an electrician. When Jason Sutherland, electrician, arrived at the 900 level to begin trouble shooting the electrical system, Martinez returned to the job of leveling the Galloway and curb ring. DiCamillo sent Ray Vaughn, miner, to relieve Sutherland on the 900 level so he could check for faults in the Galloway. Sutherland instructed Vaughn to reset the breaker if the power failed so the pumps would keep running, then got in the bucket and proceeded to the Galloway. DiCamillo went to the third deck to meet Sutherland. When the bucket arrived at the Galloway chairs, he yelled to Sutherland that he was going to ring the bucket down to the third deck. The signal was given but the guillotine failed to release the bucket rope from the crosshead. Light signals intended to alert workers that the hoistman was lowering the bucket were inoperable due to the power failure. After letting out rope to a point indicating the bucket was 2-1/2 foot below the shaft bottom, the hoistman called on the phone to ask if there was a problem because no one had signaled him to stop. DiCamillo immediately pulled the bell cord to stop the bucket. At about the same time, the guillotine released and the bucket fell, striking Howard, who was walking beneath it, forcing him through the deck doors to the bottom of the shaft. Charles Martinez was hit by flying material and knocked to the deck. He crawled over to the bucket where he could hear moaning. Sutherland was still in the bucket, seriously injured. Martinez contacted the hoistman, telling him to call for help and raise the bucket because he could see boots extending from beneath it. The top lander, Gretchen Wilkins, contacted Getchell Gold for their ambulance. Martinez and another miner got in the bucket and assisted Sutherland as they traveled to the surface. Sutherland was transported to Humboldt General Hospital and life flighted to Washoe Medical Center in Reno, NV, where he was treated for his injuries. Howard was brought to the surface and transported to Humboldt General Hospital in Winnemucca, Nevada where he was pronounced dead. CONCLUSION The primary cause of the accident was the Galloway being out of level when the bucket arrived at the chairs. Only one side of the guillotine opened, preventing the bucket from releasing. Damage and modification to the crosshead, which caused the linkage arms to contact the chairs at different heights, also contributed to the accident. Personnel being permitted to walk beneath the suspended bucket contributed to the severity of the accident. CITATIONS/ORDERS Order No. 7957439 Issued on May 27, 1997, under the provisions of Section 103(k) of the Mine Act to ensure the safety of persons during investigation operations and until the affected areas of the mine could return to normal. This order was terminated on May 31, 1997. Citation No. 7957440 Issued on May 26, 1997, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 57.16009. Order No.7957441 Issued on May 28, 1997 under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 57.14100(b) Order No. 7957444 Issued on May 28, 1997, under the provisions of 104(d)(1) of the Mine Act for violation of 30 CFR 57.18002(a). Citation No. 7957446 Issued on 06-03-97, under the provisions of 104(a) of the Mine Act for violation of 30 CFR 57.19077. /s/ Gary L. Cook Mine Safety and Health Inspector /s/ David A. Kerber Mine Safety and Health Inspector Approved by: JAMES M. SALOIS, District Manager Related Fatal Alert Bulletin:  [FAB97M32]
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