DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Metal and Nonmetal Mine Safety and Health
ACCIDENT INVESTIGATION REPORT
SURFACE NONMETAL MINE
FATAL FALL OF PERSON ACCIDENT
Demolition Dynamics, Incorporated
Martin Marietta Aggregates
Cayce, Lexington County, South Carolina
August 19, 1995
Don B. Craig
Supervisory Mine Inspector
Mine Safety and Health Inspector
Mine Safety and Health Administration
135 Gemini Circle, Suite 212
Birmingham, Alabama 35209
Gary Russell Anderson, project superintendent, age 43, was fatally injured at about 9:30 a.m. on August 19, 1995, when he fell approximately 150 feet from a bridge conveyor to the quarry floor. The victim had a total of 18 years experience at this occupation, all with Demolition Dynamics, Incorporated a contracting company.
The MSHA field office in Columbia, South Carolina was notified of the accident by a telephone call from Randy Wollett, manager of South Carolina operations for Martin Marietta Aggregates, at 10:59 a.m. on August 19, 1995. An investigation was started on August 21, 1995.
The Cayce Quarry, a multiple bench granite operation, owned and operated by Martin Marietta Aggregates, was located at 2125 State Street in Cayce, Lexington County, South Carolina. The mine is an open pit quarry operation with a crushing and finishing plant.
The principal operating official was Richard Anthony Durden, plant manager. A total of forty-nine persons was employed and worked two, 10-hour shifts a day, 5 1/2 days a week.
Granite was drilled, blasted, crushed, sized and stockpiled on site. The finished product was used in concrete, asphalt and for other purposes in the construction industry.
The victim was employed by Demolition Dynamics, Incorporated, an independent contractor located in Greensboro, Guilford County, North Carolina. The contractor performed demolition work on an old abandoned conveyor system at this operation. The principal operating official was Steven Raymond Pettigrew, president. A total of 6 contractor employees was working at this job site at the time of the accident.
The last regular inspection of this operation was conducted March
PHYSICAL FACTORS INVOLVED
The old abandoned conveyor system being prepared for demolition, consisted of a series of four towers, connected by inclined conveyors, which at one time had been used to transport material from the quarry to the secondary plant located on the top of the highwall.
The accident occurred at the last conveyor known as the bridge conveyor, connecting the tower to the quarry rim. It was approximately 164 feet long, seven feet wide and eight feet high.
The conveyor frame was secured on one end to the 150 foot high
Number 1 tower located in the quarry and at the other end to a
support leg structure. The leg structure consisted of a single
steel 10 inch by 2-1/2 inch channel iron on each side of the
bridge conveyor connected with cross braces to each other. The
structure was approximately fifteen feet high, and was located 43
feet back from the quarry rim. A separate walkway, away from and
at an angle to the bridge conveyor, also existed between the 150
foot tower and the quarry rim. Demolition work was to be done by
systematically placing explosive charges at designated points in
the conveyor frame and its supporting structures. Additionally,
some support beams were being removed and others were notched
with oxygen/acetylene torches to weaken the structure. The
accident occurred on the fourth day the contractor had been
working in preparation for dismantling the conveyor system.
DESCRIPTION OF THE ACCIDENT
Gary Russell Anderson (victim) reported for work at 6:30 a.m., his regular starting time. After placing charges on the conveyor support tower legs and wiring them, he was instructed to go to the bridge conveyor frame to place charges on it. Meanwhile, Rufus Cooksey, explosive technician, and Guadaloup Gutierres Almarz, laborer, were instructed to use an oxygen/acetylene torch to cut the braces from the support leg structure. They cut the cross braces and began cutting a horizontal brace which connected two of the legs, when the support leg structure shifted causing the conveyor frame to tear away from the tower in the quarry. The conveyor frame, which remained connected to the support structure, fell about 20 feet and remained suspended over the rim of the quarry. The victim, who was working on the conveyor frame near the tower, fell approximately 150 feet to the quarry floor.
Steve R. Pettigrew, president, who was working on the adjacent walkway and witnessed the accident, immediately ran to his pick-up truck and drove into the quarry to the victim. He felt for a pulse and found none.
Shortly thereafter, the Lexington County ambulance service and
Lexington County Coroner were summoned. The victim was
pronounced dead at the scene by the coroner. The cause of death
was massive body trauma.
The direct cause of the accident was the removal of braces which
weakened the structure of the support legs while employees were
working on the conveyor frame.
Order No. 4522601 was issued on August 21, 1995, under the provisions of Section 103(k):
A fatal accident occurred on August 19, 1995, involving the old "ladder conveyor system" at the Martin Marietta Aggregates' Cayce Quarry. This order prohibits anyone from initiating any repair or modification of any component of the old "ladder conveyor system" until an authorized representative of the Secretary of Labor reviews the accident and releases the area.
This order was terminated on August 25, 1995. The old "ladder conveyor system" has been released so that the components can be disposed of in any manner that is agreeable with the mine owner.
Citation No. 4522603 was issued on September 25, 1995, under the provisions of 104(a) for violation of Standard 56.11001:
An employee was fatally injured while preparing a bridge conveyor and its support structure for demolition. Preparation included the notching of steel support braces with oxygen-acetylene torches and the placement of explosive charges to be detonated at the time of demolition. The victim had accessed the bridge conveyor to place charges while at the same time another worker was removing portions of the bridge conveyor's support structure. This removal compromised the integrity of the support to the extent it would no longer support the bridge conveyor. The entire structure collapsed, causing the victim to fall approximately 150 feet to the quarry floor. His access, egress and work location were not safe under the procedures used in this demolition work.
This citation was terminated on September 25, 1995.
The requirements of 30 CFR, 56.11001 have been discussed with management.
Respectfully submitted by:
/s/ Donald B. Craig
Supervisory Mine Inspector
/s/ Darrell Brennan
Mine Safety and Health Inspector
Related Fatal Alert Bulletin: