DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Metal and Nonmetal Mine Safety and Health
REPORT OF INVESTIGATION
Underground Metal Mine
(Gold)
Fatal Powered Haulage Accident
February 2, 2000
Meikle Mine
Barrick Goldstrike Mines, Incorporated
Carlin, Eureka County, Nevada
ID No. 26-02246
Accident Investigators
Dominic V. Vilona
Supervisory Mine Safety and Health Inspector
Curtis R. Petty
Mine Safety and Health Inspector
F. Terry Marshall
Mechanical Engineer
Darren J. Blank
Civil Engineer
Peter P. Montali
Mine Safety and Health Specialist
John R. Turner
John C. Kathmann
Training Specialists
Originating Office
Mine Safety and Health Administration
Western District
2060 Peabody Road, Suite 610; Vacaville, CA 95687
Lee D. Ratliff, District Manager.MIA 2000-06
OVERVIEW
Rick L. Brandner, miner, age 45, was fatally injured on February 2, 2000, when he backed a water truck into an open stope. The accident occurred because a berm or bumper block had not been provided at this dump location to prevent overtravel.
Brandner had a total of two years mining experience, seven months as a miner at this operation. He had received training in accordance with 30 CFR Part 48.
GENERAL INFORMATION
The Meikle Mine, a multilevel underground gold mine, owned and operated by Barrick Goldstrike Mines, Inc., was located 27 miles north of Carlin, Eureka County, Nevada. Principal operating officials were Donald Prahl, vice president and general manager; Richard Quesnel, mine manager; Steven Long, mine superintendent; and David Sheffield, superintendent of safety and health services. The mine was normally operated two, 12-hour shifts a day, seven days a week. A total of 340 persons was employed; of this number, 288 worked underground.
Gold-bearing ore was drilled and blasted in open stopes. Broken material was transported 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 plant refinery for removal of impurities and pouring into "ore" bars. These bars were transported to refineries off site for final processing prior to sale.
The last regular inspection of this operation was completed on November 2, 1999. Another inspection was conducted in conjunction with this investigation.
DESCRIPTION OF ACCIDENT
On the day of the accident, Rick Brandner (victim) reported for work at 7:30 p.m., his regular starting time. Brandner was assigned by Robert Anderson, foreman, to operate the water truck and wet roadways at the underground work areas. Work proceeded normally through the shift. At about 3:00 a.m., Brandner was wetting the roadway in the north haulage drift on the 1525 level when he encountered Bruce White, miner, who was operating a front-end loader near the intersection of the 3575 drift.
White had just completed loading a truck with rock from a stockpile located near the dump at the stope in the 3475 drift. After loading the truck, White cleaned the drift and pushed the remains of the stockpile and the berm into the stope. The dump site was left without a berm while he went to move a concrete barrier from the north haulage drift to the stope. The concrete barrier was to be installed at the edge of the stope as a dump site restraint.
White stopped the loader and waited while Brandner drove the water truck into the 3525 drift, before retreating down the north haulage drift. As White passed by, he noticed Brandner had stopped the water truck. White parked his loader and walked toward a forklift parked nearby. As he passed by the 3475 drift, he saw the water truck backing toward the open stope. White unsuccessfully attempted to signal Brandner by waving his cap lamp.
The truck continued backing and traveled over the dump into the open stope. White went for help and met Lucian Labbe, foreman, en route. They radioed for assistance, then traveled to the bottom of the stope on the 1600 level. They checked Brandner for vital signs, but found none. Paramedics arrived a short time later and Brandner was transported to the surface where he was pronounced dead by the county coroner. Death was attributed to blunt force trauma.
INVESTIGATION OF THE ACCIDENT
MSHA was notified at 4:05 a.m., on the day of the accident by a telephone call to William Wilson, assistant district manager, from David Sheffield, superintendent of safety and health services for the mining company. An investigation was started the same day. MSHA's accident investigation team traveled to the mine and conducted a physical inspection of the accident site. The team interviewed a number of persons and reviewed documents relative to the job being performed by the victim along with his training records. An order was issued pursuant to Section 103(k) of the Mine Act to ensure the safety of miners. A representative of miners had not been appointed at this mine.
DISCUSSION
The accident occurred in the 3475 drift on the 1525 level of the mine. The drift was advanced off the north haulage drift and had a slight upward grade. The drift was about 15 feet high and the width varied from 12 to 19 feet. This drift was developed directly above another on the 1600 level. Long holes, connecting the two drifts, were drilled and blasted. Broken rock was loaded from the 1600 level. Mining had stopped about 120 feet from the point where the 3475 drift intersected the north haulage drift leaving a 75-foot drop off from the edge of the open stope to its bottom, located at the 1600 level. Observations indicated no instability of the drift floor at the point where the truck went over the edge. Skid marks were not apparent; however, marks made by the undercarriage were evident along the edge.
Reportedly, a three-foot berm of waste rock had been built at the point where the 3475 drift ended at the open stope. Twenty feet back from the edge of this stope a plastic fence had been installed across the drift and anchored to the ribs. Ore had previously been dumped and stockpiled in this drift near the fence.
This drift was being prepared for access to begin backfilling the mined out open stope. As part of this process a concrete barrier, similar to a jersey barrier, was usually installed on its side to facilitate dumping over the edge. A concrete barrier about 10 feet long, 2.7 feet wide, and 2 feet high was located at the intersection of the north haulage drift and 3525 drift.
The vehicle involved in the accident was a 4-wheel drive, low profile, articulated, model A-64, water truck, manufactured by Getman Corporation. It was powered by a 4-71 TI Detroit Diesel engine coupled to a Clark 2800 transmission, which had three speeds in both forward and reverse directions. The vehicle was approximately 24 feet long, 7 feet wide, and 7 feet high. A 1450- gallon capacity water tank, which was approximately rectangular in shape and measured 11 feet long, 5.7 feet wide and 3.75 feet high, was mounted on the rear.
The truck was equipped with a parking brake and a service brake. The service brakes were hydraulically-applied, wet disc brakes on each side of both axles and were controlled by a foot pedal. A hydraulic pump supplied pressure to two separate systems, one for each axle, to provide secondary service braking in the event of a failure in either system. The parking brakes were spring applied, hydraulically released (SAHR), which were integral to the service brake system's four hydraulic wheel cylinders, two on each axle, and were controlled by a push-pull valve. The same components as the service brakes were used to generate parking brake force on both the front and rear axles.
The brake system was severely damaged during the accident and recovery. Functional testing of the complete brake system could not be done; however, subsystem and individual component testing was performed. No defects were found with the service brake system.
The brake adjustment procedure in Getman's maintenance manual was to apply a parking brake release pressure of 1000 psi, tighten the wheel cylinder adjuster nut to 50 inch-pounds and then back the nut off 12 turns. The adjuster nuts for the front axle brakes were found to be about one-half turn too tight and the adjuster nuts for the rear axle brakes were found to be about one-quarter turn too loose with parking brake release pressures of approximately 1000 psi. All four of the wheel cylinders maintained the parking brake release pressures during these tests and all four of the parking brake springs applied the brakes when this pressure was released. The dash- mounted, push-pull, parking brake control knob was found in the "off" position (pulled out).
The wet disc brake components were disassembled and inspected. The friction plate thicknesses were measured and ranged from 0.174 to 0.182 inches. A new friction plate has a thickness of 0.190 inches and can be worn 0.020 inches before replacement is required according to Getman's maintenance manual. The contact surfaces of the separator plates of the wet disc assemblies were all shiny in appearance and none of the assemblies showed signs of component warping when meshed together by hand.
The service brake valve, Mico 06-466-206, was removed and installed on a similar Getman machine. The brake pedal supplied approximately 1500 psi to both the front and rear service brakes when the accumulator's charge pressures were allowed to reach 2000 psi and the service brake pedal was fully applied. According to Mico's specifications on this brake valve series, the brake valve output pressure should be 1500+/- 75 psi. The service brake valve output pressure was within specifications.
No fresh fluids were visually observed around the breathers of either the front or rear differentials and the fluid level of both differentials were slightly below the fill plug. The system configuration of the wheel cylinders and axle housing was such that if a hydraulic leak occurred on the service side of a wheel cylinder, it may eventually flood the axle differential housing with additional fluids.
Functional testing of the transmission could not be done due to the damage it sustained during the accident. The transmission housing was broken in half, exposing some of the gear clusters. Internal damage was such that several gears were found outside the transmission in the immediate area of the transmission.
The transmission controls consisted of two selector levers which were located to the right of the operator's seat, one for speed control and one for directional control. Both controls used mechanical levers to move push-pull cables. These cables controlled the location of hydraulic valve body pistons located on the front left section of the transmission. The directional control lever had three positions, forward, neutral, and reverse. This lever was found in the "forward" position. The speed control lever had three positions, first, second, and third. A bolt with a washer was installed in the "third" position's gate to block this speed from being selected. This lever was found in the "first" position. Both control levers moved with resistance throughout their ranges when operated by hand. The directional selector lever moved smoothly throughout its range when the cable's connecting pin was removed on the transmission side. The speed selector lever moved with slightly less resistance than previously when the cable's connecting pin was removed on the transmission side.
The truck sustained severe damage during the accident and the water tank separated from the chassis. The right rear section of the chassis was pushed forward while the front nose of the machine was pushed rearward, indicating that these areas sustained direct impacts during the accident. The water tank was found upside down with the rear of it pointing toward the entrance to the drift. The truck chassis was found upright with the front of the machine pointing toward the entrance to the drift. The articulation joint of the machine was intact, but both the front and rear axle housings were broken. The front axle housing separated from the machine and was found in two main pieces while the rear axle housing remained connected to the chassis with the right side wheel broken off at the axle.
Lighting on the machine was controlled by two dash-mounted switches. A push-pull switch operated two lights mounted on the front of the machine. A rotational switch operated five additional lights. Of these five lights, two were mounted within the rear bumper of the machine and two were mounted on the top of the rear of the water tank. One light was mounted on the radiator shroud facing the rear of the machine, reportedly to illuminate the front and top areas of the water tank. No additional lighting existed in the accident area.
The accident, along with the recovery of the machine, broke the lens of one of the two lights mounted in the rear bumper. A buildup of crusty material remained on the lens of the light still intact within the bumper even after it was cleaned with water and a soft brush. This condition made the lens translucent and not transparent. This light had electrical continuity through the single input power wire and chassis when tested. The wiring for the rear lights had been torn apart at the articulation area and at connections near the lights within the rear bumper. Visual observations of these exposed wire ends revealed shiny copper colored areas, indicative of fresh tearing. Testing of the wiring circuit segments and switches for the area work lights indicated that the switches were in the "on" position and that the electrical integrity of the lighting systems still on the machine was not compromised except for the torn wires and broken bulbs. The lights and subsequent wiring going to the rear bumper light connection, mounted on the rear of the water tank, were torn off during the recovery of the machine and remained within the stope. An operator who had driven the machine three days prior to the accident stated that all of the machine's rear lights were operable and provided adequate illumination.
The machine was delivered from the manufacturer with a front water-spray system that consisted of one variable stream nozzle mounted on the front area of the machine. The type of water stream and its direction was controlled by the operator using a joystick-type control. It was reported that the front spray system required very high maintenance and that it was eventually disabled by removing the variable spray nozzle and some related components, but the controls remained within the operator's compartment.
The rear spray system provided area watering for the ribs and mine floor through the use of seven nozzles mounted on the rear portion of the machine. A nozzle was mounted on each of the rear corners and rear sides. The three remaining nozzles were mounted on the rear bumper of the machine. A hydraulic water pump, controlled by the operator using a push-pull valve, pressurized the system. The system had three water valves, one for each group of nozzles, to control water flow to these nozzle groups. Each valve could be opened or closed by the operator using a toggle switch. All three of these switches mounted within the operator's compartment were found in the "off", or "closed", position. According to an operator of this machine, the three water valves were stuck in the "on", or "open" positions, and the water pump's push-pull control valve located within the operator's compartment was used to control the operation of the rear spray system. It was also reported that with the three water valves stuck in the "on", or "open" positions, the spray system allowed water to gravity feed through the system with the pump off. Attempts to determine if the water sprays were "on" at the time of the accident were inconclusive due to the damage sustained. Any water spraying from the rear, side mounted nozzles would have impeded the operator's visibility as the truck was being backed into the drift.
The male portion of the lap belt for the operator was found underneath the seat and not connected to the female portion. The casing to the latch mechanism was torn off, the button return spring was missing, and the button was damaged. Parts of these components were found with the debris on the floor of the operator's compartment. The seat belt latching mechanism was functional when the release button was moved into position by hand. The victim was found on the stope floor approximately three feet from the left rear corner of the machine.
The operator of this truck sat facing sideways toward the machine's longitudinal axis in the left front corner of the machine. The geometric design of the machine and the location of the operator created blind areas to the right side and rear of the vehicle. An operator of this machine stated that he could see part of the area immediately behind the vehicle only when the rear was articulated away from the operator. This operator also stated that a foot rest, which had been welded to the floor of the operator's compartment, had been installed at the mine to support the operator's left foot. This foot rest allowed an operator to support his body weight on his left foot so he could lean backward out of the compartment to increase visibility of the left side and left rear area of the machine. The operator stated that this was one reason, along with the need to frequently get on and off the machine, why the seat belt might not be used. The machine was not equipped with side-view mirrors. The operator's blind areas inherent in this type of equipment contributed to the accident. The operator could not readily see if a berm was present behind the machine.
No safety defects in the machine's systems were found that would have caused or contributed to the accident.
The mine operator had written standard operating procedures pertaining to mucking in and guarding open stopes. However, those procedures did not provide for safety while removing berms for short periods of time as occurred during this accident.
A review of the company's Part 48 training records indicated that the victim had received task training on operation of the water truck on July 20, 1999.
CONCLUSION
The cause of the accident was the failure to maintain a berm, bumper block, or impeding device at the stope's dumping location. The driver's restricted visibility while backing into the drift was a contributing factor.
ENFORCEMENT ACTIONS TAKEN
Order No. 7967252 was issued on February 2, 2000, under provisions of Section 103(k) of the Mine Act:
A fatal accident occurred at this operation on February 2, 2000, when a water truck backed into an open stope resulting in fatal injuries to the operator. This order is issued to assure the safety of persons at this operation and prohibits all activity at the 3475 stope and all accesses into this stope until MSHA has determined it is safe to resume normal operation in this area. The mine operator will obtain approval from an authorized representative for all actions to recover and/or restore operation to the affected area.This order was terminated on March 27, 2000, after it was determined that this area of the mine could resume normal operations.
Citation No. 7979202 was issued on May 30, 2000, under the provisions of Section 104(a) of the Mine Act for violation of 30 CFR 57.9301:
A fatal accident occurred at this operation on February 2, 2000, when a miner backed a water truck into an open stope on the 1525 level. Berms, bumper blocks, or similar impeding devices were not provided at the edge of the open stope.This citation was terminated on May 30, 20000, after a cement barrier was installed at the dump point. All employees were instructed that a berm, bumper block, or similar impeding device was required to be in place at all dumping locations.
APPENDICES
1. List of persons present during the accident investigation (See Below)
2. List of persons interviewed during the investigation (See Below)
3. Sketch of the accident site
4. Plan view of 1525 level - accident site
Related Fatal Alert Bulletin:
FAB2000M06
APPENDIX A
Persons participating in the investigation
Barrick Goldstrike Mines, Inc.
Richard Quesnal .................................Mine ManagerState of Nevada, Mine Safety and Training Section
David Sheffield ...................................Superintendent of Safety and Health Services
Jimmy Jannetto ...................................Underground Safety Supervisor
Steven Long.........................................Mine Superintendent
Joseph Rhoades....................................Mine InspectorMine Safety and Health Administration
Cindy Hartman.....................................Mine Inspector
Dominic V. Vilona ..............................Supervisory Mine Safety and Health InspectorAPPENDIX B
Curtis R. Petty .....................................Mine Safety and Health Inspector
F. Terry Marshall..................................Mechanical Engineer
Darren J. Blank.....................................Civil Engineer
Peter P. Montali....................................Mine Safety and Health Specialist
John R. Turner......................................Training Specialist
John C. Kathmann................................Training Specialist
Persons Interviewed
Barrick Goldstrike Mines, Inc.
Steven Long, Mine Superintendent
Lucien Labbe, Supervisor
Robert Anderson, Supervisor
Ronald Christiansen, Lead Miner/Water Truck Driver
Dwight Trautmann, Miner
Bruce White, Miner
James Henry, Miner
Gerald Goodale, Miner
Theodore Carlson, Mechanic
Christopher Hensler, Miner
David Geretts, Miner
Joel Kindle, Water Truck Driver