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UNITED STATES
DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION

Rocky Mountain District
Metal and Nonmetal Mine Safety and Health

ACCIDENT INVESTIGATION REPORT
SURFACE METAL MINE
FATAL POWERED HAULAGE ACCIDENT

Phelps Dodge Morenci, Incorporated (mine)
I.D. No. 02-00024
Phelps Dodge Morenci, Incorporated
Morenci, Greenlee County, Arizona

January 25, 1996

By

Richard R. Laufenberg
Supervisory Mine Safety and Health Inspector

Steven P. Ryan
Mine Safety and Health Inspector

Originating Office
P.O. Box 25367 DFC
Denver, CO 80225-0367
Robert M. Friend
District Manager

GENERAL INFORMATION



Eric P. Hout, truck driver, age 26, was fatally injured on January 25, 1996, at approximately 5:20 a.m., when he backed his truck through the dump berm while attempting to dump a load of copper ore. Hout had a total of eight weeks and four days mining experience, all at this mine; five weeks and four days experience as a truck driver. There were no witnesses to the accident.

Clarence E. Ellis, mine safety and health inspector, Mesa, Arizona, arrived at the Phelps Dodge Morenci mine safety office at approximately 6:55 a.m., the day of the accident. Ellis had scheduled a closeout conference for a regular inspection recently completed. Ellis was notified of the accident by H. L. Boling, safety and hygiene supervisor.

The mine, owned and operated by Phelps Dodge Morenci, Inc., was located at 4521 U.S. Highway 191, Morenci, Greenlee County, Arizona. Copper ore was drilled, blasted and loaded on trucks by electric-powered shovels. Ore was then transported to various locations throughout the mine in preparation for milling/crushing. Mine employment consisted of 2,475 persons. The work schedule was 3, 8-hour shifts a day, 7 days a week.

Principal operating officials for Phelps Dodge Morenci, Inc. were:
Timothy R. Snider, president
Donald J. Quinn, mine manager
Harold L. Boling, safety and hygiene supervisor


The training plan required under 30 CFR, Part 48, Subpart A was approved on May 11, 1979, and revised on October 19, 1993.

The last regular inspection of this operation was completed on January 25, 1996.

PHYSICAL FACTORS INVOLVED



The accident occurred at the northeast end of the 6000L King Placer copper leach dump. Distance from the dump entrance to the accident site was approximately 700 feet. The top of the dump was flat with ample space for drivers to turn and back up. A dump berm averaging 3 to 4 feet in height was provided. The berm at the accident scene measured 37 inches high, with a 7 feet 6-inch wide base. Slope distance from the top of the dump to the bottom where the truck impacted was 444 feet. Vertical drop from these points was 258 feet, constituting a 73% slope with an angle of repose of approximately 36 degrees.

Involved in the accident was a model 789 Caterpillar 190 ton haul truck, Serial No. 92C00362. The truck was equipped with a six speed automatic power shift transmission. Brake systems were oil- cooled multiple disc brakes on the front and rear wheels, a parking brake, and a spring-applied secondary braking system. Tests of the brake systems after the accident revealed no mechanical defects.

Outside distance between the right and left dual wheels was 22 feet 9 inches. Distance between the rear wheel impressions in the berm was approximately 30 feet. The angle of the truck to 1the dump berm was approximately 50 degrees at the point of overtravel through the berm.

Empty weight of the truck was 264,080 pounds. A computer printout recorded the weight of the previous load before the accident to be 412,000 pounds.

The truck was equipped with an approved roll-over protection structure and a seatbelt meeting the requirements of ANSI/SAE J1166. The left strap of the seatbelt was found wrapped twice around the bed dump lever after the accident. The exterior of the cab was intact with minor damage. Front, rear and left door windows were missing from the cab. Damage in the interior of the cab was limited to the gear console area adjacent and to the right of the operator's seat.

A portable light plant equipped with four, 1,000 watt bulbs was operating at the dump at the time of the accident.

DESCRIPTION OF THE ACCIDENT



Eric Hout, truck driver, reported for work at 11:00 p.m., on January 24, 1996. David R. Grove, assistant shift supervisor, instructed Hout and other C-shift truck drivers about their work schedules. Grove then issued a computer line-up sheet that gave the drivers their truck assignment.

At 11:34 p.m., Hout logged in on his truck and began hauling from the 51 shovel to 6060H dump. He continued hauling to the 6060H dump until 3:40 a.m. At that time the 51 shovel moved into a different grade of ore and the truck drivers were directed to the 6000L leach dump. At 5:18 a.m., Hout left the shovel with his third load of ore. Floyd Dockins, truck driver, was loaded after Haut and arrived at the dump at approximately 5:30 a.m. He observed an opening in the berm. Dockins exited his cab and looked over the dump edge. He saw marker lights of a truck at the bottom of the dump. He returned to the cab and radioed for help, giving his location.

Upon hearing Dockins' radio message David Jackson, truck driver; Mike Stegall, field supervisor; and Grove proceeded to the accident site. Grove was the first person to reach the truck. He found Hout sitting on the ground in front of the left rear wheels. Hout was conscious and responsive. Grove treated the victim's injuries.

A short time later Jackson, Dockins, and Stegall arrived and assisted Grove in moving Hout to a safer location. Dockins noticed a severe laceration on the victim's left arm and applied pressure to control the bleeding. Moments later Hout stopped breathing and cardiopulmonary resuscitation was administered. Information concerning Hout's condition was relayed to Robert Sheldon, a physician assistant at the top of the dump. Sheldon instructed Grove to transport the victim to the top.

Hout was pronounced dead at 7:10 a.m., as the result of multiple blunt injuries.

CONCLUSION



The initial impact of the truck at the base of the dump ejected the victim through the rear cab window. The rear end of the truck bed embedded into the opposite bank and the truck chassis dropped to the ground causing a second impact. The victim was found on the ground in front of the left rear wheels.

The primary cause of the accident was failure to maintain control of the truck while backing to the dump berm. A second factor was the berm did not impede the truck from overtraveling or overturning at the dump location. Contributing to the severity of injuries sustained was failure to wear the seatbelt.

VIOLATIONS



The following order was issued during the investigation:

Order No. 4650357, 103 (k)
Issued 1/25/96, at 0700 hours.

At about 0520 hours, an accident occurred at the 6000L King Placer mine dump. A 190 ton CAT haul truck backed over the dump and slid a distance of about 200 feet down the slope. This order is being issued to ensure the safety of all mine personnel until the MSHA investigation has been completed.


The following citations were issued during the investigation:

Citation No. 4665870, 104 (a)
Issued 1/27/96, at 2028 hours for a violation of 30 CFR Part56.14131 (a).

On 1/25/96, at about 0520 hours, a fatal accident occurred at the 6000L King Placer Dump. The operator of the 190 ton Caterpillar haul truck, Serial No. 92C00362, Company No. 410, was fatally injured when he was thrown through the rear window of the cab when the truck impacted the bottom of the dump. The angle of repose of the dump was approximately 36 degrees. The slope distance of the dump was approximately 440 feet from the top of the dump to the point of impact.

The operator was not wearing the seatbelt provided in the haulage truck.

The citation was terminated on 1/27/96, at 2100 hours.


Citation No. 4665871, 104 (a)
Issued 1/27/96, at 2105 hours for a violation 30 CFR Part 56.9101.

On 1/25/96, at about 0520 hours, a fatal accident occurred at the 6000L King Placer Dump. The operator of the 190 ton Caterpillar haul truck, Serial No. 92C00362, Company No. 410, was fatally injured when he failed to maintain control of the haul truck while it was in motion. The operator backed his haul truck through the berm while in the process of dumping his load. The truck traveled approximately 440 feet down the slope of the dump. The angle of repose of the dump was approximately 36 degrees.

The citation was terminated on 1/27/96, at 2155 hours.


Citation No. 4665872, 104 (a)
Issued on 1/27/96, at 2156 hours for a violation of 30 CFR Part 56.9301.

On 1/25/96, at about 0520 hours, a fatal accident occurred at the 6000L King Placer Dump. The operator of the 190 ton Caterpillar haul truck, Serial No. 92C00362, Company No. 410, was fatally injured when he backed through the dump berm. The berm was approximately 7 feet 6 inches wide at the base and 37 inches high where the truck backed through. The berm did not prevent the hazard of overtravel and overturning at the dump location.

The citation was terminated on 1/31/96, at 1415 hours.



Respectfully submitted by:

/s/ Richard R. Laufenberg
Supervisory Mine Safety and Health Inspector

/s/ Steven P. Ryan
Mine Safety and Health Inspector


Approved by,

Robert M. Friend
District Manager
Related Fatal Alert Bulletin:
Fatal Alert Bulletin Icon [FAB96M02]