DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
ROCKY MOUNTAIN DISTRICT
Metal and Nonmetal Mine Safety and Health
Report of Investigation
Surface Nonmetal Mine
Fatal Powered Haulage Accident
November 11, 1999
North Branford Quarry
Tilcon Connecticut, Inc.
North Branford, New Haven County, Connecticut
ID No. 06-00012
Charles W. McNeal
Supervisory Mine Safety and Health Inspector
Robert L. Carter
Mine Safety and Health Inspector
James L. Angel
Mine Safety and Health Administration
230 Executive Drive, Suite 2
Cranberry Township, PA 16066-0260
James R. Petrie, District Manager
On November 11, 1999, Kenneth Treloar, haul truck operator, age 49, was fatally injured when he was run over by the rear wheels of his truck. The truck was stopped on a slight grade, its engine was running, and its transmission was in neutral. The accident occurred because the truck's park brake had not been set before the operator left the vehicle's cab. Additionally, although the vehicle was equipped with chock blocks, they were not used.
Treloar had a total of 28 � years of mining experience, all at this mine as an equipment operator. He had received training in accordance with 30 CFR Part 48.
The North Branford quarry, a surface crushed stone operation, owned and operated by Tilcon Connecticut Inc., was located at North Branford, New Haven County, Connecticut. The principal operating official was Edward Platt, superintendent. The mine normally operated three, 8-hour shifts a day, six days a week. Total employment was 133 persons.
Traprock (basalt) was drilled and blasted from multiple benches in the pit. The broken rock was transported to the plant where it was crushed and sized. The sized material was transported by truck to various stockpiles throughout the quarry. The finished product was sold as construction aggregate.
The last regular inspection of this operation was completed on February 4, 1999. Another regular inspection was conducted following this investigation.
DESCRIPTION OF THE ACCIDENT
On the day of the accident, Kenneth Treloar, victim, reported for work at about 5:50 a.m. Upon arrival, he told several coworkers that he was not feeling well and thought he had a stomach virus. Treloar then proceeded to the shop to pick up the haul truck he normally operated. The truck was in the shop from the day before for repair of a defective left rear ride cylinder. Treloar conducted a pre-operation check of the truck for safety defects. He reportedly, noticed that the chock blocks were missing and requested another set from supply. He then began hauling screened material from the bin to the north screenings stockpile.
At about 7:00 a.m., Charles Spalty, bin operator, loaded Treloar's truck with screenings. Spalty stated that everything seemed normal. Treloar then drove the truck about one mile to the north screenings stockpile where he backed the truck to the dumping point. Treloar, however, did not dump the load. He descended from the operator's cab with the truck's engine running, its transmission set in neutral, and without setting the park brake. While he was on the ground, the truck drifted forwarded and its left rear wheels ran over him causing fatal injuries. There were no witnesses to the accident.
At about 7:20 a.m., Richard Cawley, haul truck driver, arrived at the screenings stockpile and dumped a load of material. He stated that he saw Treloar's truck stopped on the stockpile and that there appeared to be some rags behind it. Not realizing that Treloar had been run over, Cawley drove back down the stockpile's ramp. On his way to the bottom of the ramp, he passed Peter Sportino, haul truck driver, who was heading up the ramp to dump a load of material in the same area. Cawley, parked his truck at the bottom of the stockpile to drink some coffee. Seconds later, Sportino backed his loaded truck down the ramp and told Cawley that something was wrong and that Treloar was laying on the ground behind his truck.
Cawley drove back to Treloar's truck and found his body laying on the ground behind it. It was obvious that Treloar had sustained fatal injuries. Cawley and Sportino then traveled to the garage and reported the accident to Edward Platt, superintendent.
The local authorities and emergency medical personnel were immediately contacted and arrived a few minutes later. They found Treloar had sustained fatal traumatic injuries in the accident. He was pronounced dead by the local medical examiner at 9:10 a.m.
INVESTIGATION OF THE ACCIDENT
MSHA was notified at 8:30 a.m., on the day of the accident by a telephone call from Timothy Williamson, safety director, to James R. Petrie, district manager. MSHA began the investigation the same day with the assistance of mine management. The miners' representative was also present during the accident investigation. Upon arrival at the mine, an order was issued pursuant to section 103(k) of the Mine Act to ensure the safety of the miners until the affected area of the mine could be returned to normal operation.
1. The truck involved in the accident was a 1994, Euclid Model R50, 324LDC, rigid body, rear dump haul truck, serial number 74746. It was manufactured on December 21, 1992, and delivered to the company in 1994. The approximate gross vehicle weight was 198,400 pounds and its maximum load capacity was 100,000 pounds. The truck measured approximately 31 feet long and 14 feet wide. It was equipped with 24.00R35 tires.
2. The truck was powered by a Cummins VTA-28-C, 12-cylinder, 1710 cubic inch, turbo charged, after cooled, 675 horsepower diesel engine. It had an electronically controlled, automatic transmission with six forward speeds and one reverse. A single-lever shift control provided automatic shifting in all gears up to the one selected by the control lever. The torque converter had an automatic lock up feature.
3. The truck's service brakes consisted of air-over-oil actuated dry disc type brakes in the front and air-over-oil actuated, dual circuit, wet disc brakes in the rear. The front brakes were on a separate circuit from the rear brake circuits. The truck was equipped with an emergency and load/dump brake that applied the rear brakes. This brake was applied by a lever on the dashboard. The truck's parking brake was a spring applied, air released, dry-shoe type brake mounted on the rear of the transmission. The parking brake was actuated by an air valve control on the dashboard. Tests of the service and parking brakes did not identify any defects.
4. Steering was provided by a hydraulic steering system with a separate reservoir. Supplemental steering was provided by a semiautomatic electric driven pump circuit.
5. The truck's headlights, warning lights, mirrors, and backup alarm and strobe light were all in good condition. The operator's compartment was clean. There was no evidence of extraneous material that could have interfered with the operation of the truck.
6. A pre-operation checklist for the day of the accident was found in the operator's compartment. All of the items listed: parking brake, steering, lights and reflectors, tires, wheels and rims, horn, windshield wipers, mirrors, coupling devices, emergency equipment (warning triangle and fire extinguisher), and service brake were marked "OK." Treloar had signed and dated the form on the morning of the accident.
7. The truck was normally used during two shifts. The second shift operator of the truck reported there were no problems with the truck when he operated it two days before the accident. The day before the accident, the truck was taken in for repair of a leaking left rear ride cylinder. The cylinder was replaced and the truck was returned to service the morning of the accident.
8. During the investigation, none of the gages or warning lights in the operator's compartment indicated a problem with the machine when it was run. The hoist was operated and the load dumped. The hydraulic hoist system operated smoothly and had no apparent defects that would have prevented the operator from dumping the load or causing him to exit the vehicle.
9. A seat belt was present and functioned properly. Tilcon personnel stated that drivers are trained to wear their seat belts as well as to shut the engine off and set the park brake before exiting the machine. Operator's are further trained to chock the machine and Treloar, reportedly, had requested a set of chock blocks from supply the morning of the accident because he had found that the set which was normally on his truck was missing.
10. The truck was provided with a ladder at the front of the truck, located near the left front wheel, to access the operator's compartment. The ladder led to an approximately 16-inch wide walkway that provided access to the right and left side operator's compartment doors. A railing was provided along the walkway, except that it stopped adjacent to the forward edge of the left door. This permitted the left side door to swing fully open since the door was wider than the width of the walkway. As a result, when the door was open at 90 degrees to the side of the cab, a 29-inch opening existed that was not provided with a railing or other guard to prevent someone from falling off the walkway. This opening was at a critical location since the operator must immediately turn to the right after exiting the compartment to follow the walkway and not fall from the machine. The walkway was approximately 8 feet above the ground. A door stop (part no. 4003159) was available from the truck's manufacturer that would keep the door from swinging fully open and restrict the opening between the door and railing to no more than 8 inches. The door stop, however, was not installed.
11. The accident occurred on the north screening stockpile. This stockpile consisted of fine basalt sand and dust material built up by haul trucks. The stockpile was approximately 270 feet long and 150 feet wide and was ramped to a height of 35 to 38 feet. The ramp was between 40 and 60 feet wide, 400 feet long, and inclined at a 4 to 6 percent grade. There was no evidence of ground failure on the stockpile. The area where the accident occurred was near the berm at the edge of the stockpile where material is dumped. The ground sloped up to the berm at about a 2 percent grade. The stockpile was approximately level a short distance away from the berm. The berm at this location was about 3 feet high.
12. The weather at the time of the accident was clear and cold with gusting winds. The driver's door window was reportedly found in the rolled down position.
13. Immediately after the accident the truck was found on the level area of the stockpile with the engine running, the transmission in neutral, and neither the parking nor the emergency and load/dump brake applied. Additionally, the truck was not chocked and the chocks were found in the holder on the truck. No tools were found in the cab or on the ground near the machine to indicate that Treloar may have been trying to fix a problem with the truck.
14. The truck was fully loaded. The truck's tire tracks indicated that Treloar had backed the truck up to the berm. During the accident, the truck rolled about 53 feet from the berm to its final position. The tracks and the position of the front wheels after the accident, indicated that the wheels were turned slightly to the left. Treloar was found along the path of the left rear wheels approximately 34 feet from the center line of the rear wheels where they had contacted the berm. This placed him approximately 19 feet from the center line of the wheels after the truck came to rest. He was found laying face down on the ground with his hands outstretched above his head. A cigarette was found in his mouth. Based on Treloar's position and blood found on the tires, it was determined that only the left rear wheels of the truck had run over him.
15. During the investigation, the fully loaded truck was placed in its position at the berm immediately before the accident. Since the grade in this area is approximately 2 percent sloping away from the berm, the truck drifted forward when the brakes were released. The truck rolled along an arc, again due to the front wheels being turned to the left. The truck stopped on the level section of the stockpile and then rolled backwards slightly. The final position of the truck was near its position after the accident.
The primary cause of the accident was the failure to set the park brake before exiting the operator's cab.
Order No. 7726931 was issued in November 11, 1999, under the provisions of section 103(k) of the Mine Act.
A fatal accident occurred at this operation at about 7:10 a.m., on November 11, 1999, when a haul truck ran over it's driver. This order is issued to assure the safety of persons at this operation until the mine or affected areas can be returned to normal operation. The mine operator shall obtain approval from an Authorized Representative of the Secretary for all activities in the affected areas.This order was terminated on November 13, 1999, when it was determined that the conditions which contributed to the accident no longer existed and normal mining operations could resume.
Citation No. 7729408 was issued on December 13, 1999, under the provisions of section 104(a) of the Mine Act for violation of 30 CFR 56.14207.
A haul truck operator was fatally injured at this operation on November 11, 1999, when he was run over by the rear wheels of his truck. The operator had exited the truck with the engine running and the transmission in neutral. The park brake was not set nor were the chock blocks used.This citation was terminated on December 15, 1999, when the mine operator re-emphasized its policy requiring mobile equipment operators never to leave their vehicle unattended unless the park brake is set, the transmission is in the park position, and the chock blocks are set in place. All mobile equipment operators were re-instructed in this policy.
Related Fatal Alert Bulletin:
Persons Participating in the Investigation
Tilcon Connecticut Inc.
Gary Wall, manager, quarry divisionInternational Brotherhood of Operating Engineers, Local 478
Timothy J. Williamson, safety director
Edward Platt, superintendent
Joseph Pascarilla, miners' representativeLaw Office, Heenan, Althen, & Roles
William K. Doran, attorneyNorth Branford Police Department
Ronald I. Trench, sergeantMine Safety and Health Administration
Charles W. McNeal, supervisory mine safety and health inspectorAPPENDIX B
Robert L. Carter, mine safety and health inspector
James L. Angel, mechanical engineer
John Newby, mine safety and health inspector
Tilcon Connecticut Inc.
Peter Sportino, truck driverNorth Branford Police Department
Richard Cawley, truck driver
Charles Spalty, bin operator
Ronald I. Trench, sergeant