DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Rocky Mountain District
Metal & Nonmetal Mine Safety and Health
ACCIDENT INVESTIGATION REPORT
UNDERGROUND METAL MINE
FATAL FALLING/SLIDING MATERIAL ACCIDENT
Stillwater Mining Company Mine
I.D. No. 24-01490
Stillwater Mining Company
Nye, Stillwater County, Montana
August 21, 1995
By
William Tanner, Jr.
Supervisory Mine Safety and Health Inspector
Michael S. Okuniewicz
Mine Safety and Health Inspector
Originating Office
P.O. Box 25367 DFC
Denver, CO 80225-0367
Robert M. Friend
District Manager
GENERAL INFORMATION
Kenneth R. Goode, age 38, was fatally injured on August 21, 1995, at approximately 7:10 p.m., when he was engulfed by wet ore that broke free of a hang-up in a raise. Goode had a total of 18 years mining experience, the last 2-1/2 years at this mine as a miner class 1.
Robert M. Friend, district manager, Rocky Mountain District, was notified of the accident at 10:10 p.m., August 21, 1995, by Christopher H. Allen, manager of safety and environmental affairs. An investigation was started on August 22, 1995.
The Stillwater Mining Company was an underground platinum/palladium operation with an associated mill. The mine had been in continuous operation since March 1986 and employed 448 full-time employees, of which 271 worked underground. The work schedule was three, 8-hour shifts per day, 5 days a week. At the time of the accident, 80 miners were underground.
Ore was mined from vertical veins by conventional overhand cut-and-fill, and sublevel stoping. The stopes were accessed through vertical raises which were driven from horizontal drifts. Mine access drifts were driven at different elevations beginning at 5,000-feet above sea level. Drifts, bored by a tunnel boring machine, measured 14-feet in diameter. Drifts cut by conventional methods measured 10- by 12-feet.
Operating officials were:
Charles R. Engles, Chairman and Chief Executive Officer
John E. Andrews, President Chief Operating Officer
John E. Thompson, Mine Manager
Christopher H. Allen, Manager of Safety and Environmental Affairs
Stillwater Mining Company had an MSHA-approved training plan under 30 CFR, Part 48.
The last regular inspection of this operation was conducted July
24 to August 10, 1995.
PHYSICAL FACTORS INVOLVED
The accident occurred at the 5620 chute, located at the 5600 crosscut on the 5000 east level. Ore from the chute was transferred to 6.5-ton ore cars pulled with a 15-ton Brookville diesel locomotive on a 36-inch gage track.
The 5620 chute serviced the 5200 east level raise that was bored 6-feet in diameter, 210-feet high, at approximately 80 degrees. The chute was manufactured by Fran's Welding Machine, Inc., in Billings, Montana, and was equipped with an air-operated, top opening, arc-gate. The chute assembly was installed at the bottom of the raise in a concrete-lined frame that formed a 3-feet high by 6-feet wide opening. The chute was bolted to 1/2-inch thick, 4-1/2-inch I-beam support legs on the north and south side with four, 1-inch diameter, grade eight bolts, which were 2-1/2-inches long and spaced 1-foot apart. Sometime during the five year period that this chute had been in service, the mounting flanges, on each side of the chute, had been reinforced with 1/2-inch steel where it was bolted to the support legs.
Reportedly, the last time ore had been removed from the 5620
chute was on August 17, 1995. Ore was left in the raise for over
four days prior to the day of the accident. Ninety seven,
3-1/2-yard buckets of wet ore that ran out of the raise during
the accident was removed from the drift. This calculated to be
approximately 280-tons. In addition, mine water ran into the top
of the raise at approximately 2-gallons per minute. This
accounted for the ore being wet and sticky.
DESCRIPTION OF THE ACCIDENT
Kenneth R. Goode, victim, reported for work at 4:00 p.m., on August 21, 1995. Randy Johnson, foreman, instructed Goode and Duane Hudson, coworker, to go to the 5000 east level and start pulling ore from the 5620 chute. Goode and Hudson proceeded to the assigned area to begin loading ore cars.
Hudson backed ore cars under the chute while Goode proceeded to the chute controls. Upon operating the chute gate, ore would not flow out of the chute. Goode and Hudson, looking up into the chute, saw a hang-up of material 8 to 10-feet above the chute gate. A decision was made to spray the ore with water to free it up. Water had no effect on the hang-up so they decided to blast it loose with explosives.
Goode and Hudson taped a 1-1/2-inch diameter by 16-inch stick of Magnafrac emulsion, along with prima-cord on the end of a 20-feet, 2-inch plastic pipe and positioned it at the hang-up. The blast was initiated with a blasting cap that was secured to the end of the prima-cord.
The miners blasted the hang-up four or five times, waiting 15 to 20 minutes between blasts to allow the smoke to clear. Goode and Hudson were able to load three cars with ore that was loosened by the blasts. Goode was unable to load the fourth car. He repeatedly opened and closed the chute gate, banging it against the lip. No additional ore flowed.
As Goode started walking toward the chute he motioned to Hudson, who was located on the locomotive, to come back to the chute. Goode indicated that they might have to blast again. As Goode was looking into the chute, he suddenly yelled. Both miners turned and ran away from the chute area.
As Hudson was running away, he felt ore hit the back of his leg, knocking him down. After getting up, he realized that Goode was not behind him and that the ore had stopped running. He went back to the area where he thought Goode might be located and yelled but got no response. Hudson ran to the mine pager-phone, located approximately 14-feet from the chute controls, and called for help.
Johnson, the foreman, who was already en route to the area, heard the call on the mine pager and arrived within minutes. Johnson and Hudson immediately started digging between buried ore cars and along the rib opposite the chute, with their hands. This was the area where they thought Goode might be trapped. Rescue efforts continued as additional people arrived at the accident scene.
Goode was found between an ore car and the rib, approximately
14-feet opposite of the chute. The deputy coroner, Donald E.
Osgood, from the Stillwater County Sheriff's Office, Stillwater,
Montana pronounced Goode dead at the scene at approximately 10:45
p.m. Goode was then transported to the Smith Funeral Chapel in
Billings, Montana.
CONCLUSION
The accident was caused by the failure of the 5620 ore chute mounting assembly. The chute assembly did not provide support for loads imposed during mining operations.
A contributing factor to the accident was allowing ore, saturated
with mine water, to set for days in the 6-feet diameter, 210-feet
ore raise.
VIOLATIONS
The following order was issued during the investigation:
Order No. 3908597, 103 (k)
Issued 8/22/95, at 0600 hours.
A fatal accident occurred at the Stillwater mine on August 21, 1995, at 7:10 p.m., when two miners were trying to free a chute hang-up at the 5600 crosscut, 5620 chute, and muck came loose and buried one miner. This area is located on the 5000 E level.
This order prohibits any work other than to recover the victim until an observation of the accident site determines the area to be safe.
Terminated 9/5/95, at 1334 hours.
The following citation was issued during the investigation:
Citation No. 3908599, 104 (a)
Issued 9/5/95, at 1226 hours for a violation of 56.3360.
An accident, which resulted in a fatality, occurred on August 21, 1995, when a miner was covered with ore. Two miners were attempting to free a hang-up in the 5620 ore raise chute when approximately 280-tons of wet ore suddenly broke loose, ripping out the steel raise chute assembly from the steel set I-beams. The impact of the ore caused severe damage to the bolts that secured the chute assembly.
Investigation and examination revealed that the ground support for the 5620 ore raise chute was not adequate. The chute mounting design did not provide support for loads imposed during mining operations.
Respectfully submitted by:
/s/ William Tanner, Jr.
Supervisory Mine Safety and Health Inspector
/s/ Michael S. Okuniewicz
Mine Safety and Health Inspector
Approved by:
Robert M. Friend
District Manager
Related Fatal Alert Bulletin:
[FAB95M27]