DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Accident Investigation Report
Surface Nonmetal Mine
Fatal Other Accident
Contractor ID No. DVZ
U.S. Borax Incorporated
Boron, Kern County, California
ID No. 04-00743
July 28, 1996
Edward E. Lopez
Mine Safety and Health Inspector
David A. Kerber
Mines Safety and Health Inspector
Western District Office
3333 Vaca Valley Parkway, Suite 600
Vacaville, Ca 95688
Fred M. Hansen
Quinn Allen Richardson, field service mechanic, age 34, was fatally injured and Peter Martin, lead field mechanic, age 37, was seriously injured at 12:03 p.m., on July 28, 1996, when the wheel they were removing from a front-end loader blew off the hub. Both men were contractor employees performing work at the mine site. Richardson had four years of mining experience, including one month with this company. Martin had 16 years of mining experience, four years with this company as a lead mechanic. Both men had received MSHA approved Part 48 training for contractors through a technical college. Neither man received required Part 48 hazard training for this mine site, nor had they received task training specific to this type loader. The mine's Part 48 Training plan was approved by MSHA July 10, 1979 and was last revised January 24, 1994.
Terry W. Cleveland, safety manager for U.S. Borax Inc., notified MSHA at 2:30 p.m., on the day of the accident. An investigation was begun the same day.
Richardson and Martin were employees of DOM-EX INC., a company with 48 employees that dealt in new and used equipment and spare parts. The two men had been dispatched to dismantle purchased equipment, including the front-end loader involved in the accident, and prepare the equipment for shipment to company headquarters in Hibbing, Minnesota. The principal officials for the DOM-EX INC. were Daniel Motter, vice president, and Peter Martin, lead field mechanic.
The Boron Operations was a multiple bench open pit borax mine owned and operated by U.S. Borax Incorporated. The mine was located near Boron, Kern County, California. Principal officials were Preston S. Chiaro, vice president, and Terry W. Cleveland, safety manager. The mine normally operated three 8-hour shifts, seven days a week. A total of seven hundred fifty employees worked at the mine site.
The last regular inspection, of this operation was completed on April 27, 1995. A regular inspection following the accident was completed on October 31, 1996.
The equipment involved in the accident was a 1981 LeTourneau L-800 front-end loader, serial number 1178. The loader had been moved the day of the accident from the mine salvage yard to the staging area for disassembly. Wooden blocks were placed under the loader by the DOM-EX employees to facilitate wheel removal.
At the time of the investigation, the 16-yard loader was intact with the exception of the right front wheel. The wheel, including the tire and split rim, was lying on the ground, between the loader and the contractor's truck, a few feet from the damaged right front hub. Damage to the hub consisted of the cover plate's upper rear quarter being bent outward, with a three and one-half inch gap between it and the hub.
The Bridgestone series L5 tire measured seven and one half feet in diameter and including the wheel weighed approximately five thousand pounds. In normal use the tire would have contained water and air and been inflated to 100 pounds per square inch. The tire was still on the split rim, which had a two inch gap between its two sections. The rim liner protruded through the gap and showed signs of damage. The valve stem's air valve was still in place.
Prior to disassembly, the two piece rim was held together with sixteen, 3/4" by 2" capscrews (rim bolts). The wheel was secured to the loader hub with forty-eight 1" by 3" capscrews (lug bolts). The investigation disclosed that all of the rim bolts and 41 of the lug bolts had been removed. The remaining seven lug bolts had been cut with a torch and were protruding from the hub. Six bolts appeared to have been completely cut in two while the seventh looked as if it snapped while being cut. After the accident the torch was found partially detached from its hoses with oxygen and acetylene spewing.
The manufacturer's maintenance manual required that the tire be deflated to zero psi and the air valve be removed from the valve stem prior to removal of the rim bolts. The manual further stated that, "Failure to follow standard safety precautions could be devastating".
A DOM-EX INC., Ford LTL 9000 diesel boom truck was parked parallel to the loader, approximately fifteen feet away. It received no damage from the accident.
The weather on the day of the accident was clear and warm with temperatures climbing over 100 degrees Fahrenheit.
DESCRIPTION OF ACCIDENT
Quinn Allen Richardson (victim) and Peter Martin arrived at the mine at 7:11 a.m., on July 28, 1996. They were granted access by the guard at the mine gate and proceeded to the salvage yard where the LeTourneau L-800 front-end loader was parked. They had intended to drive the loader to the staging area but found that it was inoperable. The men then drove their vehicle to the truck maintenance shop seeking assistance. Michael Newling, U.S. Borax shop foreman, had his employees tow the loader to the mine staging area. The loader was delivered at approximately 10:00 a.m. and Richardson and Martin began blocking the loader off the ground. The U.S. Borax employees returned to their duties.
About noon, William Case, U.S. Borax heavy equipment milwright, saw Martin walking down the road near the tire barn, approximately three hundred feet from the staging area. Martin was not wearing his hard hat and was holding his side as if something was wrong. When Case approached, Martin told him he needed to get help for his partner. He also said that he had just regained consciousness and did not know what had happened.
Case radioed for help and then proceeded with Martin to the staging area. They found Richardson, lying face down, halfway under the rear of the boom truck. A few moments later they were joined by Newling and other employees, including an Emergency Medical Technician (EMT) and a paramedic. An assessment of the situation disclosed that there was nothing that could be done for Richardson. Martin, who had received lacerations and contusions, was administered first aid prior to being air evacuated.
The county coroner/investigator pronounced Richardson dead at the accident scene and listed the time of death as 12:03 p.m. His death was attributed to "blunt force trauma".
Martin was unable to recall events relating to the accident and there were no other witnesses to what occurred once the men began removing the first of the loader's wheels. Based on the facts observed at the accident scene and information obtained during the investigation, it was determined the two contractor employees were attempting to disassemble the wheel and remove it without deflating the tire.
Evidence at the accident scene indicated the men had not given consideration to the fact that the tire was inflated. It appears they were having difficulty removing seven of the bolts with their air wrench so they decided to cut them off with a torch. As the last bolt was being cut, the rims separated and air escaped with an explosive force. The wheel was blown off the hub striking both men.
The direct cause of the accident was the failure to completely deflate the tire and remove the valve core assembly before working on the wheel assembly. Contributing causes were the failure to follow manufacturer's written recommendations and provide appropriate training for the individuals assigned to disassemble the loader.
Order No. 4144130
Issued on July 28, 1996 under provisions of Section 103(k) of the Mine Act.
Citation No. 7953601
Issued to U.S. Borax, Inc. On July 29, 1996 under provisions of Section 104(d)(1) for violation of 30 CFR 48.31(a).
Citation No. 7953604
Issued to DOM-EX, Inc. On July 31, 1996 under provisions of Section 104(a) for violation of 30 CFR 56.14104(a).
Citation No. 7953605
Issued to DOM-EX, Inc. On July 31, 1996 under the provisions of Section 104(d)(1) of the Mine Act for violation of 30 CFR 48.31(a).
/s/ Edward E. Lopez
Mine Safety and Health Inspector
/s/ David A. Kerber
Mine Safety and Health Inspector
Approved by: Fred M. Hansen, District Manager
Related Fatal Alert Bulletin: