DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Metal and Nonmetal Mine Safety and Health
REPORT OF INVESTIGATION
Surface Nonmetal Mine
Fatal Powered Haulage Accident
July 30, 1999
Portable Plant #2
Midwest Minerals, Incorporated
Pittsburg, Crawford County, Kansas
ID No. 14-01463
James E. Kirk
Supervisory Mine Safety and Health Inspector
Mine Safety and Health Inspector
John W. Fredland, Jr.
Supervisory Civil Engineer
Mine Safety and Health Administration
Rocky Mountain District
P.O. Box 25367, DFC, Denver, CO 80225-0367
Claude N. Narramore, District Manager
Jason R. Norris, truck driver, age 26, was fatally injured at about 1:40 p.m., on July 30, 1999, when the truck he was driving overturned on a stockpile ramp. The truck stalled near the top of the ramp, rolled back a short distance and overturned pinning him underneath. Norris lost control of the truck because the vehicle was not maintained in safe operating condition.
Norris had a total of two years, eight months mining experience, all as a truck driver with this company. He had received training in accordance with 30 CFR, Part 48.
Portable Plant #2, a surface crushed stone operation, owned and operated by Midwest Minerals, Inc., was located at Pittsburg, Crawford County, Kansas. The principle operating official was Steve W. Sloan, president. The mine was normally operated one, 10-hour shift a day, five days a week. Total employment was 6 persons.
Limestone was drilled and blasted from a single bench in the pit. Broken material was loaded onto trucks and transported to the plant where it was crushed and sized. The finished product was sold primarily for use as road base material.
The last regular inspection of this operation was completed on August 27, 1998. Another inspection was conducted following this investigation.
DESCRIPTION OF THE ACCIDENT
On the day of the accident, Jason Norris (victim) reported for work at 7:00 a.m.. Norris had worked at other company-owned properties, however, this was his first day at this operation. He was instructed by Jimmy Coester, superintendent, to haul material from the crusher to a stockpile, a distance of approximately 500 feet.
Work progressed without unusual incident throughout the day. At about 1:40 p.m., Merle Gulick, truck driver, saw Norris' truck overturned on its side near the top of the stockpile ramp. He ran up the ramp to the truck and found Norris pinned underneath. Gulick determined that nothing could be done for Norris and returned back down the ramp where he met Coester and Danny Kelley, maintenance man. Gulick told them what he had seen and Coester instructed him to have someone call the local 911 emergency assistance number. Coester and Kelley continued to the accident scene. They too determined that nothing could be done for Norris. A rescue team arrived a short time later and Norris was pronounced dead at the scene.
INVESTIGATION OF THE ACCIDENT
MSHA was notified at 2:00 p.m., on the day of the accident by a telephone call from Curt Brumbaugh, safety director, to Jake DeHerrera, assistant district manager. An investigation was started the next day. MSHA's accident investigation team traveled to the mine, made a physical inspection of the accident site, interviewed a number of persons, and reviewed documents relative to the job being performed by the victim and his training records. An order was issued pursuant to Section 103(k) of the Mine Act, to ensure the safety of miners. The miners did not request, nor have, representation during the investigation.
The accident occurred on the AB-3 stockpile, which was a gravel product with a top size of 1-1/4-inch. The stockpile was approximately 40 feet high. At its base it was about 230 feet wide and 305 feet long. The dumping area on the top of the pile was roughly 95 feet wide and 180 feet long. The side slopes of the pile varied from 33 to 37 degrees. Access to the top of the pile was gained by a ramp along the western side. The ramp was typically 13-1/2 feet wide and 230 feet long. From the southwest corner of the pile the ramp sloped at a grade of 12 percent then gradually steepened near the top. The maximum grade at the top of the ramp was 16 percent.
The equipment involved in the accident was a 1969, Euclid R-22, Model 203FD, haulage truck. The maximum rated payload was 22 tons and the gross vehicle weight rating was 81,160 pounds. The truck was equipped with a Detroit Diesel 6-71N engine and an Allison CLBT 4460 transmission with six forward speeds and one reverse.
The service brake system design was air-operated, two-shoe, fixed anchor drum, "S" cam, internal expanding type arrangement at all four wheels. When the brake pedal was pushed, each chamber applied the force needed to rotate the "S" cam and push the shoes against the drum. Both front chambers were type 16. Both rear brake chambers were type 36. Each rear chamber was actually two separate chambers coupled together into one unit to serve two separate functions. The forward chamber provided service braking capability and the rear chamber provided parking brake capability. The brake chambers at the front wheels provided only service braking capability. When compressed air entered the service brake chambers, the corresponding internal diaphragms expanded, which caused the push rods to extend from the chambers and applied the service brake at each of the four wheels.
The rear portion of each rear brake chamber provided parking brake capability. Without compressed air in the parking brake portion, a self-contained spring expanded to extend the push rod and applied the parking brake. The parking brake could also be applied by pulling the park brake control on the instrument panel. Setting the park brake resulted in the activation of the same set of brake shoes at the rear wheels that the service brake activated. No parking brake capability was provided at the front wheels. The parking brake was designed to apply automatically when the system air pressure dropped below 45 psi.
The brake chamber push rod movement at the driver side front wheel was 2-1/8 inches. This push rod movement exceeded the 1-3/4-inch push rod brake adjustment limit specified for type 16 brake chambers in the Commercial Vehicle Safety Alliance (CVSA) North American Uniform Out-of-Service Criteria dated April 1, 1999. The excessive push rod movement made this a defective brake.
When the service brake pedal was pushed, the left side front wheel push rod appeared to bottom out against the brake chamber. The wheel was removed and the drum was shiny, which indicated that the brake linings were contacting the braking surface. However, the available braking force was compromised because of excessive push rod movement. This service brake chamber had a significant and audible air leak. With the engine shut down and the service brake fully applied, the system air pressure dropped from 120 psi to 90 psi in 30 seconds, to 80 psi after one minute, and to 70 psi after two minutes. Therefore, in two minutes, the air pressure fell from 120 psi to 70 psi and the available service braking capability would have fallen proportionally due to the air leak. However, with the engine at idle and the service brake fully applied, the compressor could maintain air pressure of 110 to 130 psi. The air leak created a dangerous condition. For example, if the truck quit running, the available service braking force would be quickly reduced by the air leak. It was calculated that within two minutes of the engine quitting, the service braking capability would not be enough to hold the truck on a 16 percent grade.
The right side front wheel brake chamber push rod did not move when the service brake pedal was pushed. Consequently, the brake at this wheel provided no braking effort. Rust on the inside of the brake drum confirmed that the brake had not been functional.
The push rod movement at each of the two rear wheel brake chambers was 2-1/2 inches. These push rod movements exceeded the 2-inch brake adjustment limit specified in the CVSA criteria. Both rear wheel service brakes were defective.
It was calculated that a braking force of 12,800 pounds was needed to hold the fully loaded truck on a 16 percent slope. Drawbar pull tests showed that the service brakes had marginal capability to hold the fully loaded truck when the truck was facing uphill with the air system fully charged. Pull tests also showed the service brakes did not have the capability to hold the loaded truck on the grade if the truck was facing downhill. To measure the maximum holding capability, these tests were done with a full payload so that all the tires would retain traction on the road surface and to duplicate the truck payload configuration at the time of the accident. Determinations of holding capabilities were made with the engine running. With the engine not running and the service brake applied, the air leak at the front brake chamber would quickly deplete the air pressure and decrease the holding capability.
The parking brake holding capability was measured using the same drawbar pull test. The test showed that the parking brake was not capable of holding the truck on a 16 percent grade.
Stall tests were conducted according to the procedures in Euclid Service Bulletin No. R510EH01 dated 11/96. The truck met the minimum acceptable criteria but not the preferred. The Euclid Service Bulletin stated that the "minimum stall performance limits the machine, loaded to rated capacity, to operate on grades not to exceed 12 percent. For operation sites with grades above 12 percent, use the preferred performance criteria." Since the truck was operating on a 16 percent grade and did not meet the preferred level of performance, it was being used beyond the grade recommended by the manufacturer.
The transmission shifter linkage had excessive free play and was not adjusted properly. To place the transmission into a given gear, the selector had to be moved far enough to overshoot the corresponding notch in the gear selector. For example, if the gear shift selector was placed into the first gear notch, the transmission itself would remain in neutral. To obtain first gear in the transmission, the gear selector handle had to be moved nearly into the second gear notch. Once the transmission itself was in first gear, the selector handle could be brought back to the first gear notch and the transmission would remain in first gear. After righting the truck, the position of the transmission selector handle was found to be in the first gear position.
The steering system was tested by having a driver maneuver the truck in a flat level area. The steering system operated normally and the front tires could be turned full stroke in both the left and right directions. The design of the steering system was such that hydraulic pressure to a single steering cylinder controlled the direction of the front wheels.
The cab and body of the truck were not extensively damaged as a result of the rollover.
The accident occurred because the mine operator failed to maintain the truck in safe operating condition. The service braking system and the parking brake were not maintained to allow the driver to control the truck. The transmission linkage was worn and out of adjustment. Failure to inspect mobile equipment for safety defects was a contributing factor. Failure to wear the seatbelt contributed to the severity of the accident.
Order No. 4672044 was issued on July 31, 1999, under the provisions of Section 103(k) of the Mine Act:
A fatal accident occurred at this operation on July 30, 1999, when a truck driver hauled a load of rock up the west ramp to the AB-3 material stockpile. The truck overturned and pinned the driver underneath. This order is issued to assure the safety of persons at this operation until the mine or affected areas can be returned to normal operations as determined by an authorized representative of the Secretary. The mine operator shall obtain approval from an authorized representative of the Secretary for all actions to recover person, equipment, and/or return affected areas of the mine to normal operations.This order was terminated on August 3, 1999. Conditions that contributed to the accident have been corrected and normal mining operations can resume.
Order No. 4711027 was issued on September 28, 1999, under the provisions of Section 107(a)/104(d)(1) of the Mine Act for violation of 30 CFR 56.14101(a)(1):
A truck driver was fatally injured at this mine on July 30, 1999, when the truck he was operating overturned. The loaded truck stopped near the top of a stockpile ramp and rolled backward prior to overturning. The service brake system on the truck was not capable of stopping and holding the truck on the ramp. Failure to assure that the service brakes were adequate is a serious lack of reasonable care constituting more than ordinary negligence and is unwarrantable failure to comply with a mandatory safety standard.Order No. 4711028 was issued on September 28, 1999, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 56.14101(a)(2):
A truck driver was fatally injured at this mine on July 30, 1999, when the truck he was operating overturned. The loaded truck stopped near the top of a stockpile ramp and rolled backward prior to overturning. The parking brake was not capable of holding the truck on the ramp. Failure to assure that the parking brake was adequate is a serious lack of reasonable care constituting more than ordinary negligence and is an unwarrantable failure to comply with a mandatory safety standard.Order No. 4711029 was issued on September 28, 1999, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 56.14100(a):
A truck driver was fatally injured at this mine on July 30, 1999, when the truck he was operating overturned. The loaded truck stopped near the top of a stockpile ramp and rolled backward prior to overturning. Three separate safety defects existed on this truck and were cited as causes of this accident. The truck operator had not assured that adequate pre-operation inspection had been conducted on this truck. Failure to conduct adequate pre-operation inspections is a serious lack of reasonable care constituting more than ordinary negligence and is an unwarrantable failure to comply with a mandatory safety standard.This order was terminated on October 4, 1999. The mine operator's mobile equipment inspection policy was reviewed with employees. Meetings were conducted in which equipment operators were instructed in pre-shift inspection procedures. The importance of thorough inspections to correct safety defects was emphasized.
Order No. 4711030 was issued on September 28, 1999, under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 56.14100(c):
A truck driver was fatally injured at this mine on July 30, 1999, when the truck he was operating overturned. The loaded truck stopped near the top of a stockpile ramp and rolled backward prior to overturning. Defective transmission control linkage made continued operation of this truck hazardous. Continued operation of this truck is a serious lack of reasonable care constituting more than ordinary negligence and is an unwarrantable failure to comply with a mandatory safety standard.Order No. 4711031 was issued on September 28, 1999, under the provisions of Section 104(a) of the Mine Act for violation of 30 CFR 56.14131(a):
A truck driver was fatally injured at this mine on July 30, 1999, when the truck he was operating stopped near the top of a stockpile ramp and rolled backward prior to overturning. The driver was not wearing a seatbelt.This order was terminated on October 4, 1999. The mine operator's seatbelt policy was reviewed and several meetings were conducted in which the miners were instructed to wear seatbelts at all times when operating mobile equipment.
Related Fatal Alert Bulletin:
Figure 1 - Plan View of AB-3 Stockpile - Pittsburgh Quarry, Midwest Minerals Incorporated
Figure 2 - Plan view showing position of Euclid R22 truck near top of AB-3 stockpile ramp Pittsburg Quarry, Midwest Minerals Incorporated
Persons Participating in the Investigation
Midwest Minerals, Incorporated
George Nettels, chairmanEngineering Application's, Incorporated
Steve W. Sloan, president
Curt Brumbaugh, safety director
Jimmy D. Coester, mine superintendent
Toby S. Nelson, P.E. Forensic EngineerJackson and Kelly PLLC
David Arnold, attorneyMine Safety and Health Administration
James E. Kirk, supervisor mine safety and health inspectorAPPENDIX B
Larry Aubuchon, mine safety and health inspector
Ronald Medina, mechanical engineer
John W. Fredland, Jr., supervisory civil engineer
Midwest Minerals, Incorporated
Curt Brumbaugh, safety director
Jimmy D. Coester, mine superintendent
Merle Gulick, truck driver
Danny A. Kelley, mechanic
Robbie E. Kichler, front-end loader operator
LaVern G. Fox, scale house operator