DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Western District
Metal and Nonmetal Mine Safety and Health
Accident Investigation Report
Surface Nonmetal Mine
(Sand and Gravel)
Fatal Material Handling Accident
Crystal Creek Aggregate, Incorporated
Kett Siding Mine
Redding, Shasta County, California
ID No. 04-05096
Date of Injury
April 16, 1998
Date of Death
April 17, 1998
By
John Widows
Supervisory Mine Inspector
and
Dan E. MacMillan
Mine Safety and Health Inspector
Originating Office
Mine Safety and Health Administration
Western District
2060 Peabody Road, Suite 610
Vacaville, California 95687
James M. Salois
District Manager
GENERAL INFORMATION
Harley L. Gardner, plant superintendent, age 59, was fatally injured at about 7:30 a.m. on April 16, 1998, when a 62-pound piece of wire mesh screen fell from a screen deck and struck him on the head. He died the next day. Gardner had 20 years mining experience, seven years at this mine and five years in this work activity. He had not received training in accordance with 30 CFR Part 48.
MSHA was notified of the accident by a telephone call from Jerry Comingdeer, president, at about 11:30 a.m. on April 16, 1998. An investigation was started the following day.
Kett Siding mine, a sand and gravel operation, owned and operated by Crystal Creek Aggregate, Inc., was located approximately ten miles west of Redding, Shasta County, California. Principal operating officials for Crystal Creek Aggregate, Inc. were Jerry Comingdeer, president, and J. D. Comingdeer, vice president and secretary/treasurer. The mine was normally operated one, eight-hour shift a day, five days a week. Total employment was five persons.
Rock was drilled and blasted in the pit and conveyed to the plant, where it was crushed, screened and stockpiled. The final products were sold for road building and general construction material.
The last inspection of this operation was completed on February 5, 1998. Another inspection was conducted at the conclusion of this investigation.
PHYSICAL FACTORS INVOLVED
The accident occurred at the triple deck El Jay dry screen plant. The top deck of the plant was about 17 feet above the ground. At one end of the deck, a discharge chutedirected material to the cone feed conveyor located six feet below. The chute had a metal cover which measured 18 inches wide by 68 inches long.
A service truck, equipped with a gasoline powered air compressor, was parked below the plant. The compressor was used to supply compressed air for the air tools used to remove the screen. Normal practice was to use an electric air compressor located in the storage building about 25 yards from the screen plant; however, it was not in service at the time due to electrical repairs. The electric compressor produced no discernable noise levels at the screen plant while the truck mounted compressor generated noise levels which averaged 81 dBA in the area in front of the truck. Reportedly, Gardner was hard of hearing.
The banded wire mesh screen cloth used in this operation was delivered in sections measuring five feet by eight feet. The screen was made from 1/4-inch wire with openings measuring 7/8-inch square. The screens were cut in half and used in sections. The resulting screen sections measured four feet by five feet and weighed 62 pounds. The weather was cool and clear.
DESCRIPTION OF ACCIDENT
On the day of the accident, Harley L. Gardner (victim) began his shift at 7:00 a.m., his regular starting time. At about 7:30 a.m., Gardner was at ground level below the screen plant, supervising the changing of a section of screen cloth. Charles Higdon, plant operator, was on the elevated screen deck, about 17 feet from ground level, changing the screen cloth. Higdon removed the old screen cloth and placed it on the discharge chute cover because he observed Gardner talking to Vernon Miles, mechanic. Higdon's normal practice was to drop the screen cloth over the edge of the screen plant and have it land on the ground in the area where Gardner and Miles were standing.
After Higdon placed the old screen cloth on top of the discharge chute cover, he started to install the new screen cloth. Suddenly and without warning, the old screen cloth slipped off the chute cover and started to fall towards the cone feed conveyor. Both Miles and Higdon saw the screen falling and yelled to Gardner, who had just turned his back to Miles and started walking away. Gardner did not hear their warning cries. The screen fell about six feet, bounced off of the cone feed conveyor frame, and fell an additional five feet before hitting Gardner in the head, knocking off his hard hat.
First aid was performed by those at the scene. The local emergency 911 number was called and the victim was transported by ambulance to a hospital in Redding, California, where he died the next day.
CONCLUSION
The cause of the accident was failure to maintain safe access below the screen plant, where there was a fall of material hazard. Contributing factors included: 1.)placing a four foot by five foot piece of screen cloth onto a chute cover which was only 18 inches wide, and 2.)the noise created from the truck mounted air compressor which prohibited the victim from hearing warning cries.
CITATIONS/ORDERS
Citation No. 7956899 was issued on April 17, 1998, under provisions of Section 104(d) of the Mine Act for violation of 30 CFR 56.11001:On April 16, 1998, a superintendent was [seriously] injured when a 62-pound screen cloth fell and struck him on the head. The screen cloth was being replaced on a screen plant located about 17 feet above ground level. The superintendent died of his injuries on April 17, 1998. The superintendent was aware of the work activities above him and failed to ensure a safe access below and near this area. This is an unwarrantable failure.
This citation was terminated on June 16, 1998 after the operator had provided training to all employees concerning safe access and working where there is a hazard of falling objects/material.
Related Fatal Alert Bulletin:
FAB98M15