DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
SOUTH CENTRAL DISTRICT
Metal and Nonmetal Mine Safety and Health
Accident Investigation Report
Fatal Powered Haulage Accident
Jobe Concrete Products Incorporated
El Paso, El Paso County, Texas
I.D. No. 41-03278
January 19, 1998
Edward E. Lopez
Supervisory Mine Safety and Health Inspector
Henry J. Mall
Mine Safety and Health Inspector
Moises A. Lucero
Mine Safety and Health Inspector
Mechanical Engineer, Mine Equipment Branch, A&CC
Mine Safety and Health Administration
1100 Commerce Street, Room 4C50
Dallas, Texas 75242-0119
Doyle D. Fink
Valentine Moreno, equipment operator, age 72, was fatally injured at about 1:30 p.m., on January 19, 1998, when his truck bed overturned and he was ejected through the windshield. Moreno had a total of one and one half years mining experience, the past two weeks as a truck driver at this mine. He had not received training in accordance with 30 CFR Part 48.
MSHA was notified at 3:37 p.m., on the day of the accident by a telephone call from David Macias, production manager. An investigation was started the following day.
The South Quarry, an open pit limestone operation, owned and operated by Jobe Concrete Products Inc., was located east of El Paso, El Paso County, Texas. The principal operating officials were Armondo Garcia, supervisor and David Macias, production manager. The mine was normally operated one, 8-hour shift a day, five and one half days a week. A total of twelve persons worked at the mine.
Limestone was extracted by drilling and blasting multiple benches. Broken material was hauled by front-end loader and truck to the plant where it was crushed, sized and stockpiled. The finished products were sold primarily for general industry and road construction.
The last regular inspection of this operation was completed on October 9, 1997. Another inspection was conducted following the investigation.
PHYSICAL FACTORS INVOLVED
The truck involved in the accident was a Terex Model 2766C, 27.5-ton capacity all-wheel drive, articulated dump truck. It was powered by a Cummins LT-10C-250 turbo charged diesel engine.
The truck was equipped with two independent braking systems. One was a service brake which incorporated an air over hydraulic, disc brake system with independent circuits for the front and rear brakes which was applied with a foot pedal in the operator's compartment. It could also be applied by selecting the emergency position on a three position switch in the operator's compartment. Activation of the service brakes would occur automatically when the air pressure fell below 45 pounds per square inch (psi). A warning device mounted on the dashboard would also activate with the loss of air pressure. A separate park brake system consisted of a spring applied, air released disc brake on the rear drive line. This brake could also be applied manually by selecting the park position on the three position switch in the operator's compartment. It automatically engaged when the air pressure dropped to below 45 psi. Following the accident, the switch was found in the �release' position.
When tested during the investigation, the park brake was found to be out of adjustment and ineffective. The service brakes, however, passed a series of tests and supported the conclusion that the service brakes were fully functional and effective.
The steering system was comprised of a cab mounted steering wheel which was connected to a steering valve under the cab floor that controlled the hydraulic flow from the engine driven steering pump to the steering cylinders. An accumulator provided emergency steering if the engine were to stall. During investigation, the system was tested and functioned correctly while the engine was running. The emergency system was tested with the engine shut down and the hydraulic accumulator provided emergency steering capability as designed.
Safety features equipped on the truck included a certified roll over protective structure (ROPS) and a seat belt which met the requirements for operator restraint systems for off-road work machines. Both were found in good working condition.
The truck was normally used to haul broken limestone from the quarry to a primary crusher located in the plant yard, a distance of approximately one thousand feet.
This road declined at approximately 10 degrees or 17 percent. It was graded smooth and was bermed properly from top to bottom. The road wound slightly down the hill to a switchback curve located approximately 300 feet from the crusher. Traffic on the road was one way only.
Tire tracks found on the roadway identified the path of the truck. The tracks, identified as the left side tire tracks, veered off the left side of the roadway approximately 250 feet uphill from the switchback curve. They followed the left shoulder for about one hundred feet to a bump in the shoulder and then crossed at a forty-five degree angle to the right shoulder of the roadway. The tracks then made a straight line down the right shoulder, across the switchback to a berm constructed of large rocks. Paint marks as well as scrape marks were imprinted on the large boulders constructing the berm.
The truck came to rest with the cab upright and the cargo box laying on it's right side approximately thirty feet from where the markings were found on the rocks. There were no skid marks on the roadway to suggest that the brakes had been applied.
Damage to the truck was assessed at the scene. The cargo box front tandem axle and wheel assembly were damaged, as were some lubrication lines. The engine compartment lid although undamaged was fully extended outward in the open position. The cab of the truck remained pristine with the exception of the windshield. It was found laying perpendicular across the top of the engine.
DESCRIPTION OF ACCIDENT
On the day of the accident, Valentine Moreno (victim) reported for work at 7:00 a.m., his regular starting time. He began his shift by conducting a pre-shift safety inspection of his assigned haul truck. After recording no defects, he began hauling rock from the quarry to the jaw crusher.
Moreno hauled rock all morning without incident and took a lunch break between noon and 1:00 p.m. At about 1:20 p.m. he left the quarry load out area headed for the jaw crusher with his tenth load.
Moreno was not seen by anyone as he descended the decline. Investigation of the scene, however, indicated that he was in control of the truck on the first half of the trip down the hill. He then veered onto the left shoulder where the left wheels stayed until hitting a bump which caused the truck to cross over to the right hand shoulder. Once on the right shoulder, the truck continued straight down to the bottom of the decline where it crossed the roadway at the switchback and struck a berm on the opposite side. The collision with the berm caused the truck to turn and the cargo box to overturn. When the cargo box turned onto it's right side, the truck came to a sudden stop. This caused the engine compartment to open and Moreno to be ejected from the cab.
At about 1:30 p.m. Juan Garibay, maintenance man, looked up from where he was working in the rock plant and noticed a cloud of dust. As the dust settled Garibay saw the truck and immediately drove his service truck to the scene. Upon arrival, Garibay found Moreno lying across the engine, face down on top of the windshield and noticed that the engine was still running. Moments later, Armondo Garcia arrived at the scene and checked Moreno for a pulse. Finding none the two men placed a jacket around Moreno's head and turned the engine off.
At about 1:50 p.m., the local rescue squad arrived accompanied by an ambulance. Moreno was pronounced dead at the scene a short time later by the county medical examiner.
The accident occurred because the driver failed to maintain control of the truck. Why he failed to do so could not be ascertained. Failure to wear a seat belt contributed to the severity of the accident.
Order Number 4457292, was issued on January 19, 1998 under the provision of Section 103(k):
At about 1330 hours on January 19, 1998, the haul truck driver was fatally injured at this mining operation. This order is issued pursuant to section 103K of the 1977 Mine Act to ensure the safety of miners until a systematic evaluation of conditions is conducted as to what caused the fatality.This order was terminated on January 24, 1998 after it was determined that the mine could return to normal operation.
Citation Number 7925870, was issued on February 24, 1998 under the provision of Section 104(a), for violation of 30 CFR Part 56.9101:
A fatal accident occurred at this operation on January 19, 1998, when a truck driver lost control of the truck he was driving while en route from the quarry to the crusher. The bed of the articulated truck overturned when the vehicle struck a rock berm at the bottom of the pit access ramp. The cab remained upright, but the victim was thrown through the windshield. An examination of the vehicle and roadway did not reveal defects affecting safety or unsafe conditions.Citation Number 7925871, was issued on February 24, 1998 under the provision of Section 104(d)(1), for violation of 30 CFR Part 56.14131a:
A fatal accident occurred at this operation on January 19, 1998, when a truck driver lost control of the truck he was driving while en route from the quarry to the crusher. The bed of the articulated truck overturned when the vehicle struck a rock berm at the bottom of the pit access ramp. The cab remained upright, but the victim was thrown through the windshield. The Victim was not wearing a seatbelt. No effective effort was made to ensure truck seatbelts were worn. The instructions to wear seatbelts were in English, the victim spoke Spanish. The operator did not establish a successful practice of following-up to see that seatbelts were being worn. This is an unwarrantable failure to comply with a mandatory standard.
Related Fatal Alert Bulletin: