MINE SAFETY AND HEALTH ADMINISTRATION
ROCKY MOUNTAIN DISTRICT
Metal and Nonmetal Mine Safety and Health
Underground Metal Mine
Fatal Powered Haulage Accident
Grizzly Bear Mine
I.D. No. 05-03608
ZMK Mine Construction, Incorporated
Ouray, Ouray County, Colorado
July 21, 1999
Fred H. Tisdale
Supervisory Mine Safety and Health Inspector
Danny A. Frey
Mine Safety and Health Inspector
Mine Safety and Health Administration
Rocky Mountain District
P.O. Box 25367, DFC, Denver CO, 80225-0367
Claude N. Narramore, District Manager
Joseph M. Mattivi, mechanic/safety trainer, age 47, was fatally injured at about 10:30 a.m., on July 21, 1999, when the bucket of a loader fell on him. Mattivi was operating the loader when it developed a hydraulic oil leak. He stopped the loader and raised the bucket, then attempted to tighten a hose connection. The fitting broke, causing the bucket to fall. The bucket was not supported or blocked.
Mattivi had a total of 15 years mining experience, all as a mechanic, nine years at this operation. He had received training in accordance with 30 CFR Part 48.
DESCRIPTION OF ACCIDENT
On the day of the accident, Joseph Mattivi (victim) reported for work at about 7:45 a.m., his normal starting time. After a meeting with the miners, he used the loader to move ore from the mine portal to the stockpile, a distance of approximately 200 feet. Apparently, Mattivi realized that the loader had an oil leak and stopped it to see what repairs were needed. Having determined that a hose fitting was leaking, he raised the bucket and attempted to tighten the fitting on the right side lift cylinder. When Mattivi tightened the fitting it broke causing the bucket to fall, pinning him between the lift arms and the loader frame.
At about 11:00 a.m., Aaron Calhoon, a former employee, arrived at the mine to borrow a pump. Calhoon saw the loader parked near the mine portal with the bucket down and the engine idling. Calhoon loaded the pump onto his truck and then looked for Mattivi to inform him that he was taking the pump. Calhoon noticed a trail of oil on the ground and assumed that Mattivi was repairing the loader. He walked to the loader and saw the victim trapped between the bucket lift arms and the frame of the machine. Calhoon attempted to lift the bucket by activating the control levers, but was unable to do so. He ran to the change room and radioed the mine construction shop located in Ouray and reported the accident. Shop personnel called the local 911 emergency assistance number and a rescue team was dispatched to the mine.
At about the same time, Ryan Reese, truck driver, came out of the mine with a load of ore. He checked Mattivi for vital signs and found none. Unable to raise the bucket using the controls, Reese and Calhoon obtained two jacks and began to raise the bucket. The rescue team arrived and removed Mattivi. He was pronounced dead a short time later by the county coroner.
The Grizzly Bear Mine, an underground gold/silver operation, owned and operated by ZMK Mine Construction, Incorporated, a division of Savage Mining and Oil Company, Incorporated, was located just south of Ouray, Ouray County, Colorado. The principal operating officials were Angelo Zanett, president, and Richard Zanett, vice president. The mine was normally operated one, 8-hour shift a day, five days a week. A total of five persons was employed.
Gold and silver ore was mined by drilling and blasting the mineralized vein at various underground locations. The ore was then transported by LHD and small trucks to the portal.
The last regular inspection of this operation was completed on July 8, 1999.
INVESTIGATION OF THE ACCIDENT
MSHA was notified at 11:55 a.m., on the day of the accident by a telephone call from Richard Zanett to Claude Narramore, district manager. 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. A number of persons were interviewed and documents relative to the job being performed and the victim's training records were reviewed. An order was issued pursuant to Section 103(k) of the Mine Act to ensure the safety of miners. The miners did not request, nor have, representation during the investigation.
The equipment involved in the accident was a 1987, Eimco Jarvis Clark, Model 921, load-haul-dump unit powered by a Deutz, F5L912W, 65.5 horsepower diesel engine. The bucket, an ejector type with a capacity of one-yard, was empty at the time of the accident.
The loader bucket was supported by two lift arms. The up and down movement of the lift arms was controlled by a pair of DTS hydraulic cylinders, 24 inches long and 5 inches in diameter. When hydraulic pressure was applied to the blind (bottom) ends of the cylinders, the bucket moved up. When hydraulic pressure was applied to the rod (top) ends of the cylinder, the bucket lowered.
The blind end ports of the two bucket lift cylinders were teed together and the rod end ports were teed together. If pressure was released from one cylinder, the parallel porting arrangement would cause a loss of pressure in the other.
The hose to the blind end of the right bucket lift cylinder was found disconnected (broken). With the bucket arms elevated and this hose disconnected, the consequent loss of pressure in both of the bucket lift cylinders allowed the lift arms to fall. Examination of the disconnected hose showed that the female JIC (37 degree flare) swivel nut hex fitting on the hose was split lengthwise. The male fitting in the cylinder consisted of a male O-ring boss to male JIC (37 degree flare) 90 degree fitting. The O-ring side was threaded into the cylinder port. The thread size on both the male and female JIC was 3/4"-16. The hose was a 5/8" Gates 10C2AT SAE 100R2AT with a 2,750 maximum psi pressure rating printed on the side. These types of fittings and hoses are commonly used in hydraulic systems.
The bucket lift, tilt and eject controls all self-centered to the neutral position upon release of the valve handles. The hydraulic system on this machine was not provided with load-locking valves to prevent the sudden collapse of a hydraulic cylinder in the event of a hose failure. Four combination wrenches were found at the accident site. The wrenches were 3/4", 13/16", 7/8" and 15/16". The 7/8" wrench fit the disconnected (broken) fitting.
CONCLUSIONThe direct cause of the accident was failure to block or secure the bucket prior to attempting to repair the oil leak.
Order No. 7911634 was issued on July 21, 1999, under the provisions of Section 103(k) of the Mine Act:
A fatal accident occurred at this operation on July 21, 1999, when a mechanic/safety trainer was crushed when a front-end loader bucket fell on him. This order is issued to assure the safety of persons at this operation until the mine or affected areas can be returned to normal operations as determined by an authorized representative of the Secretary. The mine operator shall obtain approval from an authorized representative for all actions to recover persons, equipment, and/or return affected areas of the mine to normal.This order was terminated on July 23, 1999. Conditions that contributed to the accident have been corrected and normal mining operations can resume.
Citation No. 7911635 was issued on July 22, 1999, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 57.14211(a):
A mechanic was fatally injured at this operation on July 21, 1999, when a front-end loader bucket fell on him while he attempted to repair a hydraulic oil leak. The bucket was not blocked or secured to prevent it from falling. The victim was the person with overall responsibility for the health and safety program at the mine. Failure to block or secure the bucket is a serious lack of reasonable care constituting more than ordinary negligence and is an unwarrantable failure to comply with a mandatory safety standard.This citation was terminated on September 10, 1999. Procedures for securing and blocking machinery have been initiated and all employees have been instructed to follow these procedures.
Related Fatal Alert Bulletin:
Persons participating in the investigation:
ZMK Mine Construction, Incorporated
Richard G. Zanett, vice presidentSavage Mining and Oil Company, Incorporated
Peter Klein, part owner
Ryan Reese, miner
Aaron Calhoon, student/miner
Angelo Zanett, presidentOuray County Sheriff's Department
Jerry Wakefield, sheriffOuray County Coroner's Office
Gary Miller, coronerMine Safety and Health Administration
Fred H. Tisdale, supervisory mine safety and health inspector
Danny A. Frey, mine safety and health inspector
Ronald Medina, mechanical engineer