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Accident Investigation Report
Surface Nonmetal Mine

Fatal Material Handling Accident

Azusa Plant
Transit Mixed Concrete
Azusa, Los Angeles County, California
ID No. 04-01696

November 30, 1995


Ronald G. Ainge
Mine Safety and Health Inspector

Mine Safety and Health Administration
Western District Office
3333 Vaca Valley Parkway, Suite 600
Vacaville, California

Fred M. Hansen
District Manager


Bryan W. Schmidt, mill operator, age 34, suffered a back injury on November 30, 1995 and died on October 4, 1996 due to complications from surgery. Schmidt began working at Azusa Plant while employed by P. D. Mechanical, a contractor for Transit Mixed Concrete. He was hired by Transit Mixed Concrete on August 18, 1995. He had approximately nine months mining experience, all at this mine. Schmidt had been trained in accordance with 30 CFR Part 48.

Ed Moff, safety coordinator, notified MSHA of the fatality at 2:20 p.m. on October 4, 1996. An investigation was started the following day.

The Azusa Plant was located at Azusa, Los Angeles County, California and was operated by Transit Mixed Concrete, a subsidiary of Southdown Incorporated. The corporate offices were located in Houston, Texas. Principal operating officials were Daniel J. Pellow, vice president of aggregate operations; Dale Martinez, administrative assistant; and Mark Felton, production manager. Thirty-six persons were employed, working one production and one maintenance shift per day, five days per week.

The surface sand and gravel mine had multiple benches. Material was mined with a hydraulic shovel, which loaded 85-ton haul trucks. The trucks dumped the material into a jaw crusher where it was crushed to 6-inch minus before being conveyed to the mill. Various sizes of sand and gravel were produced with cone crushers, screens and washers at the mill. The material was used in the construction and building industries.

The last regular inspection at this property was conducted July 16 through July 18, 1996.

Physical Factors

The area where the accident occurred was located at the main plant. The mill operator monitored the 30 to 35 conveyor belt operation from the plant control room. However, he routinely went into the plant each shift to clean up spilled material from areas beneath head pulleys, tail pulleys and transfer points. A bobcat front-end loader operator removed the major portion of spilled material before the mill operator shoveled the remaining material by hand. Time spent shoveling varied according to the amount of plant down time and the wetness of the material. The ground in these areas was generally level and dry, with some wet areas in the washed screening plant. On the day of the accident, the areas being cleaned were situated on level ground.

The weather was clear, with a high temperature of about eighty-five degrees.

Description of the Accident

Bryan W. Schmidt (victim), reported for work at 5:30 a.m. on November 30, 1995, his normal starting time. As the mill operator, he monitored the crushing and screening plant from the control room most of the day. Several times during the day, however, Schmidt shoveled spilled material from under conveyor head and tail pulleys. At some point during the day, Schmidt felt pain in his lower back while shoveling of material. He worked the remainder of the shift performing his normal duties. On Friday, December 1, 1995, Schmidt returned to his normal duties; however, as the day progressed the pain in his back increased as he continued to shovel spilled material.

Due to increased back pain, Schmidt was admitted to a local hospital on Saturday, December 2, 1995. He was discharged on December 8, 1995 and diagnosed with a probable acute lumbar disk herniation with nerve impingement. According to medical records, Schmidt's condition resulted in temporary total disability; therefore, he did not return to work.

For approximately ten months, Schmidt was treated for the back injury using various nonsurgical treatments, without any noticeable improvement. On September 30, 1996, Schmidt underwent elective surgery to correct the herniated disks in his lower back. Schmidt died from complications of the back surgery on October 4, 1996. According to the coroner, Schmidt suffered "pulmonary thromboembolism" [blood clot in the lung] as a result of the surgery.


The accident which resulted in the back injury was caused by the victim's hand shoveling activities while cleaning up spilled material around conveyor pulleys. The injury was probably further aggravated by continued shoveling after the victim became aware of back pain. It could not be determined if the victim was injured as a result of improper and/or prolonged use of the shovel. Complications from the surgery to correct the injury resulted in the unexpected death of victim.


No citations were issued.

/s/ Ronald G. Ainge
Mine Safety and Health Inspector

Approved by: Fred M. Hansen, Manager, Western District

Related Fatal Alert Bulletin:
Fatal Alert Bulletin Icon [FAB95M53]