MINE SAFETY AND HEALTH ADMINISTRATION
Metal and Nonmetal Mine Safety and Health
Accident Investigation Report
Underground Metal Mine
Fatal Fall of Person Accident
Dynatec Mining Corporation
ID No. WJ6
Barrick Goldstrike Mines, Incorporated
Carlin, Elko County, Nevada
ID No. 26-02246
April 1, 1999
Willie J. Davis
Supervisory Mine Safety and Health Inspector
Mine Safety and Health Inspector
Edward C. Edwards
Mine Safety and Health Inspector
Terence M. Taylor
Western District Office
Mine Safety and Health Administration
2060 Peabody Road, Suite 610
Vacaville, CA 95687
James M. Salois
Kenneth R. Stevenson, raise superintendent, age 36, was fatally injured and Louis Rogers, miner, age 39, was slightly injured at 4:10 p.m. on April 1, 1999, when they fell into an ore pass. Stevenson had 15 years mining experience, three months as superintendent at this operation. Rogers had 12 years mining experience, three months as a miner at this operation. Both had received training in accordance with 30 CFR Part 48.
MSHA was notified at 5:30 p.m. on the day of the accident by a telephone call from the superintendent of safety and health services for the mining company. An investigation was started the same day.
The Meikle Mine, a multi-level underground gold mine owned and operated by Barrick Goldstrike Mines, Inc., was located 27 miles north of Carlin, Elko County, Nevada. Principal operating officials were Donald Prahl, vice president and general manager; David Sheffield, superintendent of safety and health services; and Richard Quesnel, mine manager. The mine was normally operated two, 12-hour shifts a day, seven days a week. A total of 227 persons was employed; of this number 185 worked underground.
Both Stevenson and Rogers were employed by Dynatec Mining Corporation, an independent contractor headquartered at Richmond Hill, Ontario, Canada. Principal officials at the Meikle Mine were Roger Letourneau, project manager and Cherie Tilley, safety director. A total of 70 persons was employed at this site; of this number, 67 worked underground. Dynatec had begun sinking shafts for the mine operator at this site in March 1994. The contract, known as Phase I, ended in December 1996. Some Dynatec employees remained at the mine performing various construction projects until the Phase II Meikle expansion began in February 1999.
Gold bearing ore was drilled and blasted in open stopes. Broken material was transported from the stopes on haulage trucks to ore chutes, then crushed and hoisted to the surface. Depending on grade, the ore was either milled or hauled to a cyanide leach pad for processing. The milled or leached product was sent to the refinery for removal of impurities and pouring into dor� bars. These bars were transported to refineries off site for final processing prior to sale to customers.
Access to the mine was via the production shaft, which was sunk to a depth of 1480 feet. In early 1999, the Phase II Meikle expansion was undertaken to deepen this shaft to 1795 feet to access new production levels. Additional underground infrastructures were also needed to process this ore. These new facilities included a crushing and conveying system and an ore pass system to transfer broken ore to the crusher from the mine levels above.
Design plans specified that the crusher ore pass system would consist of two, nearly vertical, 10-foot diameter bored raises extending from the 1375 to the 1675 levels. This system would be accessed at approximately 75-foot intervals from each level. A series of transfer mechanisms would then be incorporated to allow movement of broken ore through the system.
The two raises were excavated using traditional raise bore techniques. Ground support had been installed from the 1375 to the 1525 levels. Construction of the grizzly assembly at the top of the 1525 level ore pass was underway at the time of the accident. The work consisted of removing the remaining eight to ten feet of crown at the top, installation of a winch, a galloway, and associated ground support. Cleanup of rubble and debris generated by the crown removal was underway when the accident occurred.
The accident occurred at the top of the 10-foot diameter ore pass located on the 1525 level where two miners had been cleaning blasted material from the sill area around the collar. Two other miners were working nearby in the crosscut leading to the borehole.
Three DBI/SALA block, self-retracting lifelines (SRL) were located adjacent to the collar of the 1525 ore pass. Each lifeline was a 3/16-inch diameter wire rope, 20 feet long. The devices were anchored approximately 46 inches above the floor about 7 feet from the edge of the opening. Two were on the south wall, located behind a temporary electrical panel, and the third was mounted on the opposite wall. The manufacturer recommends that the SRL be anchored as vertically as possible above the person using the system, that it be rigged so that the maximum potential fall was limited to no more than six feet, and that cable movement be free and unrestricted. A speed sensing brake system activated in the SRL if a fall occurred, stopping it, and absorbing much of the fall's energy. The SRL used by Rogers was extended across the borehole, a distance of approximately 17� feet.
Three full-body harnesses, manufactured by Miller Equipment, were in the work area. They had been used in conjunction with the SRL's earlier in the shift by two of the miners working around the open borehole. Stevenson was wearing a safety belt equipped with a D-ring but was not tied off with a safety lanyard at the time of the accident. Earlier in the shift, Stevenson had connected his safety harness to the SRL while he worked around the borehole.
On the day of the accident, Kenneth Stevenson (victim) and Louis Rogers reported for work at 8:45 a.m., their regular starting time. Before going underground, Stevenson held a safety meeting with his work crew and discussed the need to use fall protection devices while working around the ore pass. After the meeting, Stevenson and the miners went underground. Throughout the day, Stevenson worked in and around the area of the 1525 level borehole supervising the four crew members assigned to the job.
At about 4:10 p.m., Troy Wright, miner, and Rogers were cleaning around the edge of the ore pass with a shovel and blowpipe. Both men wore safety harnesses and were tied off to SRL's. Shortly before the accident, Wright unhooked his SRL and began another task away from the hole. Rogers was working his way along the edge when he stepped on a loose rock causing him to slip and fall into the opening. Stevenson, who was standing nearby observing the cleaning work, attempted to catch him and fell into the opening along with Rogers. Rogers fell approximately 12 feet before his fall was arrested by the SRL. Stevenson fell 150 feet to the bottom.
Miners converged at the bottom of the ore pass and attempted to revive Stevenson, but were not successful. A coroner arrived a short time later and pronounced Stevenson dead at the scene. Rogers was treated for minor injuries at a local hospital and released.
The accident was caused by failure to use the SLR while working around the borehole. Improperly anchoring the SRL in a nearly horizontal position may have contributed to the injuries received by Rogers.
Order No. 7967224 was issued on April 1, 1999, under the provisions of Section 103(k) of the Mine Act:
A fatal accident occurred at this operation on April 1, 1999, when a worker fell down the 1525-1675 ore pass. This order is issued to assure the safety of persons at this operation until MSHA has determined it is safe to resume normal operations in this area. The mine operator shall obtain approval from an authorized representative for all actions to recover and/or restore operation to the affected area.This order was terminated on April 3, 1999, after it was determined that the affected area of the mine could resume normal operations.
Order No. 7969918 was issued on May 18, 1999, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR §57.15005:
A fatal accident occurred at this mine on April 1, 1999, when a supervisor fell into the 1525 Crusher Ore Pass when he reached for a miner who was falling into the opening. The miner fell about twelve feet before his fall was arrested by the safety harness and lifeline he was wearing. The supervisor was wearing a safety belt, but was not tied off and fell about 150 feet. Failure to tie off near an open ore pass demonstrates a serious lack of reasonable care, which constitutes more than ordinary negligence and is an unwarrantable failure to comply with a mandatory safety standard.The order was terminated on May 18, 1999, after it was determined that all personnel had been retrained in the use of safety belts and lines..
Related Fatal Alert Bulletin:
Persons participating in the investigation:
Dynatec Mining Corporation
Roger A. Letourneau .......... project manager
Cherie M. Tilley .......... project safety director
Terry M. Tilley .......... safety director for U.S. operations
Louis Rogers .......... miner
Troy Wright .......... miner
Barrick Goldstrike Mines, Inc.
Chantel Lavoie .......... maintenance superintendent
State of Nevada Mine Safety and Training Section
Edward M. Tomany .......... chief administrative officer
James O. Frei .......... mine inspector
Mine Safety and Health Administration
Willie J. Davis .......... supervisory mine safety and health inspector
Curtis Petty .......... mine safety and health inspector
Edward C. Edwards .......... mine safety and health inspector
Terence M. Taylor .......... civil engineer.