DEPARTMENT OF LABOR
MINE SAFETY AND HEALTH ADMINISTRATION
Metal and Nonmetal Mine Safety and Health
Report of Investigation
Surface Nonmetal Mine
(Sand and Gravel)
June 30, 2000
Windsor Island Mine
Windsor Rock Products
Keizer, Marion County, Oregon
ID. No. 35-03425
Supervisory Mine Safety and Health Inspector
Mine Safety and Health Inspector
Mine Safety and Health Specialist
Eugene D. Hennen
Mine Safety and Health Administration
2060 Peabody Road, Suite 610
Vacaville, CA 95687
Lee D. Ratliff, District Manager
Felix Juarez, front-end loader operator, age 56, was fatally injured at about 10:45 a.m., on June 30, 2000, when he was struck by a backhoe bucket. Juarez had parked his loader and was assisting the backhoe operator in unplugging a pipe located under a roadway when the accident occurred. The victim died fourteen days later from the injuries he received in this accident.
The accident occurred because management failed to establish an effective maintenance program that included thorough pre-operational examinations of mobile equipment such as the backhoe. Juarez had a total of five years mining experience all at this mine. He had not received training in accordance with 30 CFR Part 46.
The Windsor Island Mine, a sand and gravel operation, owned and operated by Windsor Rock Products, was located three miles northwest of Keizer, Marion County, Oregon. The principal operating officials were William McCall, general manager, and Steve W. Pence, operations manager. The mine was normally operated one, 8-hours a day, five days a week. Total employment was 27 persons.
Material was mined from a single bench at the quarry and transported to the primary crusher by haulage trucks. The aggregate material was crushed, washed, screened, and stockpiled before being shipped to or loaded for customers.
The last regular inspection of this operation was completed on May 10, 2000. Another inspection was conducted at the conclusion of this investigation.
On the day of the accident, Felix Juarez (victim) reported for work at 6:30 a.m., his normal starting time. During the first part of the shift, Juarez operated a front-end loader loading trucks in the yard. About 11:05 a.m., Juarez noticed Michael Stewart, truck driver, digging a hole with a backhoe to uncover a plugged waterline. The line ran under the roadway between the secondary rock crushing plant and the �" minus stock pile. Juarez climbed off the loader and went to help Stewart. Juarez was standing on the left side of the backhoe when the machine's boom swing pedal apparently stuck causing the boom and bucket to swing around and strike him. He was knocked to the ground and struck his head. Stewart immediately got off the backhoe and assisted Juarez lying on the ground.
Dewey Lenaburg, truck driver, was waiting to be loaded and observed the accident. He ran over to help Stewart render aid to Juarez. Juarez lost consciousness for 15 to 30 seconds and the two men concluded that Juarez needed immediate medical attention. After he regained consciousness, the two men placed Juarez into Lenaburg's truck and transported him to a local hospital. His condition worsened and he died fourteen days later. Death was attributed to blunt force trauma to the head.
MSHA was notified at 11:40 a.m., on July 3, 2000, by a telephone call from Nancy Cody, safety enforcement manager, Oregon Occupational Safety and Health Administration, to Randy Cardwell, mine safety and health inspector, Albany, Oregon field office. An investigation was started the same day by Cardwell who visited the site, observed the backhoe, interviewed witnesses, and reviewed appropriate reports and forms. Initially, Juarez' injury was not considered serious and not immediately reportable to MSHA. In the interim, the backhoe was moved and repaired prior to the arrival of the MSHA accident investigation team on July 10, 2000. The team conducted a physical inspection of the accident site, interviewed miners, and reviewed training records relative to the job being performed by the victim. The miners did not request nor have representation during the investigation.
1. The Caterpillar Model 416 backhoe (Serial No. 5PC14893) involved in the accident was manufactured in 1991 and weighed approximately 13,000 pounds. It was powered by a Perkins 75-horsepower diesel engine. The mine operator had purchased the machine "as is" with 3200 hours on it in August 1996 from a local Caterpillar distributer. It had been used sporadically to unload supplies and dig minor excavations in and around the mine. The machine had operated 2400 hours since it had been purchased by the operator.
2. The boom swung right and left with approximately 90 degrees of movement to each side. The swing control portion of the hydraulic control valve, which allowed the boom to swing from side to side, was controlled by two foot pedals located in the operator's cab. One pedal was mounted on each side of the control panel. The pedals were connected together with a linkage to the control valve. When the right pedal was pushed down, the left pedal raised and vice versa when the left pedal was depressed. Pushing the right pedal caused the boom to swing right and depressing the left pedal pushed the boom left. When the swing control operated properly, releasing both pedals caused them to center at the same level.
3. There were two methods to stop the swing on the backhoe. One method was for the machine operator to take his feet off the pedals allowing the springs in the control valve to center the spool and stop the swing. The second method was to keep a foot on each pedal and center the spool in the control valve by using both pedals. The backhoe's operating manual, used by mechanics in the mine shop for maintenance work, did not specify a preferred method for controlling swing motion.
4. At the time of the accident, it was determined that the backhoe operator had been attempting to swing the boom to the left by pushing the left swing control. He tried to stop it from swinging too far by releasing the left pedal. It stuck and did not return to the neutral position. The operator stomped the left pedal trying to free it, but this effort was not successful.
5. During the investigation, a test was conducted to determine the maximum speed of the boom swing. It was noted that the swing cylinders slowed just before they got to the end of their stroke. The investigators were told by the manufacturer's representative that this slowing was normal. The speed test was conducted with the engine throttle set between one-half and three-quarter, which was reportedly its position at the time of the accident. With the left swing pedal completely depressed, it took approximately one second for the boom to travel from its center position until it started to slow at the end of the swing cylinders' stroke.
6. Steve Pence, operations manager, assigned Mark Valentine, mechanic, to repair the sticking pedal linkage on the backhoe shortly after the accident occurred and prior to the arrival of MSHA's investigation team. In doing so, Valentine found that the left swing pedal was sticking because of dirt and rust between the shaft and bushing around which the pedal rotated. Dirt and rust were also trapped by the bushing in the open area between the shaft and the bushing housing. He cleaned the rust and dirt from the left pedal assembly then disassembled and checked the other two shaft assemblies in the swing control linkage. After repairing and lubricating the linkage, the left pedal no longer stuck and the control(s) worked much more freely. In addition to making the above repairs, Valentine added grease fittings to the shaft housings for the left and right swing control bushings and shafts. Soon after Valentine finished his repairs, Jon Sprauer, a serviceman from the local Caterpillar distributor, arrived at the site and checked the hydraulic circuit and control linkage for the backhoe's boom swing. He did not find any problems with sticking pedals when he checked the circuit and linkage.
7. The backhoe's service records at the mine were reviewed from 1996 until the day of the accident. Some equipment operators stated that they had not reported linkage problems in writing although the mine had forms available to document any needed machine repairs. Some operators also said that they had verbally informed maintenance personnel of their concerns about difficulty with pushing the swing control pedals. Michael Stewart, backhoe operator on the day of the accident, thought this difficulty was normal. Gary Cope, wash plant operator, thought this condition was normal but told William McCall, general manager, about the stiffness of the pedals. McCall believed this difficulty was normal and did not have it investigated.
8. The backhoe was scheduled for service and maintenance by plant maintenance personnel every 250 hours. Service records at the mine indicated that the schedule had been adhered to since the machine had been purchased by the operator. Maintenance personnel indicated that records regarding backhoe maintenance defects were kept for one month after being written, then thrown away after they were reviewed to ensure that all noted items had been corrected.
9. Although a formal miner training plan was being developed by the operator, it had not been finalized nor been implemented. Some task training for employees on haul trucks, front-end loaders, and crushers had reportedly been conducted; however, no one had been task trained as required by 30 CFR Part 46 on the backhoe involved in the accident. Training on other mine equipment was reportedly conducted by an experienced person. Training continued until it was believed the employee could properly and safely operate the equipment.
10. The operator of the backhoe on the day of the accident had not received task training as required by 30 CFR 46 on the machine. He had operated similar equipment twice at other sites and this backhoe three times prior to the accident. The victim and the crusher operator used the backhoe more than the other personnel in the mine.
11. The victim had received informal on-the-job training in driving trucks and operating front-end loaders over the years, but records of that training had not been maintained by the mine operator. The victim had attended a safety meeting on April 4, 2000, during which the use of personal protective equipment was discussed. Other training received by the victim could not be determined.
The accident was caused by management's failure to establish an effective maintenance program which included a thorough pre-operational examination of the backhoe. A contributing factor was the backhoe boom's left swing control sticking due to an accumulation of rust, dirt, and lack of lubrication.
Citation No. 7976441 was issued on September 15, 2000, under the provisions of Section 104(a)of the Federal Mine Safety and Health Act of 1977 for violation of 30 CFR 56.14100(b):
An employee was injured at this operation on June 30, 2000, at approximately 10:45 a.m., when he was struck by a backhoe bucket during the excavation of a plugged water line. The bucket knocked him off his feet and he struck his head on the ground. The victim died fourteen days later as a result of the injuries. The left swing pedal linkage on the 416 Caterpillar Series II backhoe (serial no. 5PC14893) was defective in that it was stuck in position. The defect rendered the boom incapable of being controlled properly.The citation was terminated on September 15, 2000, after the swing pedal linkage was repaired.
Related Fatal Alert Bulletin:
A. Persons participating in the investigation
B. Persons interviewed during the investigation
Persons participating in the investigation:
Windsor Rock Products
William McCall . . . . . . . . . . . . . . . . . . . . . . . . . . general managerMine Safety and Health Administration
Steve Pence . . . . . . . . . . . . . . . . . . . . . . . . . . . . operations manager
Larry Larson . . . . . . . . . . . . . . . . . . . . . . . . . . . . supervisory mine safety and health inspector
Michael Burgess . . . . . . . . . . . . . . . . . . . . . . . . . .mine safety and health inspector
Emmett Sullivan . . . . . . . . . . . . . . . . . . . . . . . . . . mine safety and health specialist
Eugene Hennen . . . . . . . . . . . . . . . . . . . . . . . . . . .mechanical engineer
Persons interviewed during the investigation:
Windsor Rock Products
William McCall . . . . . . . . . . . . . . . . . . . . . . . . . . general manager
Steve Pence . . . . . . . . . . . . . . . . . . . . . . . . . . . . operations manager
Michael Stewart . . . . . . . . . . . . . . . . . . . . . . . . . .backhoe operator
Dewey Lenaburg . . . . . . . . . . . . . . . . . . . . . . . . . truck driver
Mark Valentine . . . . . . . . . . . . . . . . . . . . . . . . . . mechanic
Gary Cope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .wash plant operator