On Dec. 29, 2018 at 6:00 p.m. 25-year-old Caleb Brown began his shift at Centralia Coal Mine in Centralia, Wash.
Brown began his shift with a safety meeting led by Ronald Coleman, the night shift supervisor. Workers rotated positions every three to four hours during the shift. Coalview Centralia LLC was the contractor hired by Trans Alta Centralia Mining LLC, Centralia Mine owner and operator, to suction dredge fine coal refuse from the mine.
After the huddle, Brown drove out to the impoundment to start operating the suction dredge and replace William Bachman, a plant operator ending his shift.
Bachman informed Brown that the walking surface of the starboard side of the stern pontoon was around 1 in. below the water surface. Bachman released some tension on the stern-line and brought the pontoon up about 4 in. above the water line. Bachman then left the suction dredge, but returned when he discovered that he forgot his portable radio. He retrieved it and left once again.
Shortly after, Mathew Rumley, another colleague, discovered the power indicator lights were not on for the suction dredge. He then traveled by boat to check on the dredge and found it had sunk with only the A-frame protruding out of the water.
According to investigators, Brian Casperson, Trans Alta’s shift supervisor, called emergency responders at 7:54 p.m. A search effort was launched, and called off for poor visibility and conditions.
The next day, rescue divers recovered Brown's body in the dredge operator's compartment. He was wearing a floatation device, but the divers who found Brown said it was difficult to get the compartment door open. Medical examiners ruled Brown's cause of death as drowning.
Investigators examined the dredge, noting the hazardous conditions were "obvious and widespread." Numerous modifications were made the the equipment, including replacining the diesel engine with four electric motors and removement of port and starboard bilge pumps on the bow end of the hull. The starboard door did not line up properly with doorframe. Despite the port door lining up, the plunger was badly worn and came apart during the investigation.
Management was aware of the hazards and condition of the suction dredge yet continued to allow its operation. Investigators found an electronic file containing the observations noted during the mine operator's daily inspections, but these were not recorded in the preshift/on-shift daily report book.
Brown, who had 21 weeks of experience, died because the mine contractor did not have adequate policies and procedures regarding the suction dredge's pontoons, bilge pumps, and dredge operator’s compartment doors to safely conduct mining operations. According to investigators, the mine contractor conducted inadequate on shift examinations and took no action to correct hazardous conditions.
This was a summary of the final report prepared by Donald R. Vickers, Mine Safety and Health Administration (MSHA) acting district manager. The full contents of the report are available on MSHA's website.