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UNITED STATES
DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION

Northeastern District

ACCIDENT INVESTIGATION REPORT

Western District
Metal and Nonmetal Mine Safety and Health

SURFACE CRUSHED STONE
FATAL FALL OF MATERIAL ACCIDENT

Sonoma Rock, Mine ID No. 04-04988
C.R. Fedrick, Inc.
Sonoma, Sonoma County, California

February 24, 1995

By

Jerry A. Millard
Mine Safety and Health Inspector

Stephen A. Cain
Mine Safety and Health Inspector

Western District Office
3333 Vaca Valley Parkway, Suite 600
Vacaville, California 95688
Fred M. Hansen, District Manager


GENERAL INFORMATION

William W. Alderman, a 50-year old customer truck driver, was fatally injured, February 24, 1995 at approximately 8:30 a.m., when a stockpile face collapsed and covered him with aggregate material. The victim had worked seven years as a truck driver for his current employeer, Pipeline Excavators.

Garry Day, MSHA Western District Assistant Manager, was informed of the accident by Dee Fedrick, President, C.R. Fedrick, Inc. at 10:16 a.m., February 24, 1995. An investigation was started the same day.

The accident occurred at Sonoma Rock, ID# 04-04988, a crushed stone quarry owned and operated by C.R. Fedrick, Inc. The mine, located south of Sonoma, Sonoma County, California normally employed five people during the summer and two during the winter.

Summer months were spent extracting and processing the aggregate while work during the winter months was limited to loading material sold from the stockpile.

Principal operating officials for C.R. Fedrick, Inc. were:

Dee Fedrick, President
Joe Fedrick, Senior Vice President
Gerald L. Wood, Vice President, Administration
Barry Kiser, Foreman

MSHA is prohibited by Congressionally imposed budget restrictions from enforcing the training requirements of 30 CFR, Part 48, at this operation.

The last regular inspection was conducted November 15, 1994.

PHYSICAL FACTORS

The vehicle involved in the accident was a 1982 Kenworth highway-type truck with a dump trailer. The owner, Pipeline Excavators, had designated this vehicle as truck P10 and the trailer as PT10. The truck bed was 94 inches wide with 49 inches between the bottom of the bed and the ground. A 14 inch by 14 inch door, called an "asphalt door", was built into the tailgate.

The trailer was attached to the truck with a draw bar. The gross weight of the truck was 79,800 pounds and the net weight was 31,380 pounds.

The vehicle had been moved prior to MSHA's arrival in order to facilitate the rescue attempt. Observation of tire tracks, however, indicated that the vehicle had been parked in a "jack-knife" position, with the trailer parallel to the stockpile face and the cab perpendicular to it. Investigators were told that the truck had been found with the bed in the dump position, the tailgate closed, and the asphalt door open.

The stockpile was located near the process plant. It rose from west to east at a seven to fifteen percent grade and was 170 feet long and approximately 80 feet wide. The stockpile had been developed by using a dozer to push aggregate to the east end where trucks were loaded. As material was added the stockpile became compacted, reducing absorption capacity. This resulted in a drier product being available for sale during the winter months.

Prior to the accident, the east end of the stockpile had a vertical face that was approximately 30 feet high. A Caterpillar 966-F front-end loader had been used at the southeast corner to load haul trucks.

The investigation found that it was standard practice to load-out material from the east end of the stockpile until a vertical face developed, then move north or south and continue to load trucks. The vertical face would later slough to its angle of repose. The compacted nature of the material made it difficult to predict when the sloughing would take place.

The center of the face, a 23 foot wide section, appears to be the portion that collapsed and covered the victim.

DESCRIPTION OF THE ACCIDENT

William Alderman arrived at the mine site for his first load of aggregate at 7:19 a.m., February 24, 1995. He delivered this load to a construction site about 17 minutes from the mine. He returned for his second load at 8:21 a.m. His truck was loaded by the weighmaster, Tom Mason. Alderman then drove to the scales while Mason loaded another truck. After loading the other truck, Mason headed toward the scales and met Alderman returning to the stockpile area. Alderman told Mason he was 3,000 pounds overweight. Mason told him to dump the overload material in a flat area away from the stockpile and return to the scales.

Mason then went to the scales to weigh the other truck. After a few minutes had passed, and Alderman had not returned, Mason stepped outside and saw that Alderman's truck was backed up to the highwall, with the bed raised to the dump position. He was unable to see Alderman. Mason got on the front-end loader and drove to the stockpile. Unable to locate Alderman, he continued on to the shop area. Steve Crandell, loader operator, was in the shop but had not seen Alderman. He accompanied Mason to the stockpile where they noticed that the rear of the truck, and the trailer drawbar, were covered with aggregate. They then realized that Alderman was buried under the material. Mason went to call 911 while Crandell started to dig with a shovel.

With the help of the local fire department, the truck was pulled away from the scene to facilitate rescue efforts. The collapsed material was removed from Alderman by means of hand shoveling and a front end loader. It is estimated that he had been under the material about 20 minutes. The Sonoma County Coroner's Unit removed the victim from the mine site after determining that death was due to asphyxiation caused by compression.

CONCLUSION

The primary cause of the accident was the operator's failure to maintain a trimmed stockpile. Contributing to the severity of the occurrence was the customer driver being located in an unsafe position between the stockpile's vertical face and the rear of his truck.

CITATIONS/ORDERS

The following order and citations were issued during the investigation:

Order No. 3916616 103(k),
Issued February 24, 1995 to C.R. Fedrick, Inc.

A fatal accident (fall of material) has occurred at the plant's 3/4 inch base rock stockpile. This accident involved one truck driver who worked for Pipeline Excavators Contracting Company.

This order prohibits any contamination of the accident scene, pending an investigation by MSHA, to determine the cause of the accident.

Citation No. 4139910 104(d) (1), 30CFR, Part 56.9314.
Issued February 25, 1995 to C.R. Fedrick, Inc.

A customer truck driver was fatally injuried on 2-24-95 when a stockpile face collapsed covering him with aggregate material. The face was approximately 30-feet high and stood at approximately 70-90 degrees. Mining and processing on the aggregate materials had not been conducted since approximately November, 1994. The company had stockpiled the surplus aggregate to sell on an as needed basis during the winter months. Company officials stated that their aggregate sells better when it is free of moisture. To reduce the moisture exposure, the aggregate is compressed as it is stockpiled. This action reduces the possibility of moisture migrating into the stockpile. The company has allowed the stockpile to remain undisturbed by dozing or pushing material off the stockpile. This creates a cliff like face on the area of the stockpile where the loaders fill the haul trucks. When the stockpile becomes vertical the loader operator moves to a different location and allows the vertical face to slough off under its own weight. There was no definite time span on when the stockpile would come down. The company did not use cones, ribbon, barricades, berms or any preventions to protect this area against entry. This practice created a hazard to persons who may work or travel near the vertical face. This is an unwarrantable failure.

Citation No. 4139911 104(a), 30CFR, 56.3430.
Issued February 25, 1995 to C.R. Fedrick, Inc.

A customer truck driver was fatally injured when a stockpile face collapsed covering him with aggregate material. The face was approximately 30-feet high and stood at approximately 70-90 degrees. The victim backed his haul truck near the stockpile face to off load material from his overloaded truck. The victim positioned himself at the rear of the truck with the stockpile behind him while he attempted to shovel material from his raised truck bed.

Respectively submitted by:

/s/ Jerry A. Millard
Mine Safety and Health Inspector

/s/ Stephen A. Cain
Mine Safety and Health Inspector

Approved by:

Fred M. Hansen, Manager, Western District
Related Fatal Alert Bulletin:
Fatal Alert Bulletin Icon [FAB95M09]


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