Haul/Off Road/Coal/Ore/Pit/Quarry/Rock/Rubber Tire Truck Driver

Our mixer driver was hauling for Freeport McMoRan at their Morenci mine location, the load was rejected and sent back, driver followed the escort down a hill with a full load, lost brakes and turned the mixer on its driver's side.

On January 28, 2022, at 9:09 a.m., Monroe Caston, Jr., a 56 year-old mixer driver with three years of mining experience received fatal injuries, and David Butler, a 24 year-old mixer driver in training with two years of mining experience, received serious injuries when the cement mixer truck they were in lost control, overturned on its side, and slid into a berm. The accident occurred because the contractor that employed Caston and Butler, Tri County Materials Inc (Tri County), did not: 1) maintain braking systems in functional condition and did not remove equipment from service until defects that make continued operation hazardous were corrected, 2) conduct adequate pre-operational examinations on mobile equipment prior to operation, and 3) assure that miners wore seat belts.

1. The contractor did not maintain braking systems in functional condition and did not remove equipment from service until defects that make continued operation hazardous were corrected.

   Corrective action: The contractor took all trucks out of service and inspected the braking systems on all trucks before putting them back in service. The contractor developed written criteria for removing defective equipment from service, specifically addressing defective brakes. The contractor developed a written Standard Operating Procedure (SOP) regarding inspecting brakes (before each vehicle use). All miners were trained on the criteria to recognize and remove defective equipment from service and on the SOP.

2. The contractor did not conduct adequate pre-operational examinations on mobile equipment prior to operation.

   Corrective action: The contractor developed a written SOP regarding pre-operational examinations of mobile equipment.The SOP addresses who is responsible for performing the examinations, how to document the examination and correct the defects, where the completed documentation is turned in, and how records of corrections are kept.The contractor trained all miners on the SOP.

3. The contractor did not assure that miners wore seat belts.

   Corrective action: The contractor developed a written SOP regarding seat belt use while all vehicles are in motion and trained all miners in the SOP.

Read the full report (PDF)

Findings from MSHA's final investigation report, which supersedes the preliminary narrative above.

Activity at time of incident

Haulage Or Dump Truck

Subunit / location

STRIP, QUARY, OPEN PIT

Accident type

Struck against a moving object

Source of injury

HGHWY ORE CARIER,LRGE TRK

Nature of injury

UNCLASSIFIED,NOT DETERMED

Body part affected

HEAD,NEC

Total mining experience

3 years

Experience at this mine

2 years

Experience in this job

3 years

Degree of injury

FATALITY