Cargill SaltMining Incidents in 2013

The DC converter control card for the production hoist failed not allowing the hoist to function.

415p supervisor notified of strange sound at #3hoist. After investigating the noise it was determined to be coming from the grid coupler between gear box and drum. Evac started @430p out #1 shaft so the #3 coupler & grid could be inspected. MSHA Notified at 445p, all out by 545p. Grid was intact but contacting coupler case. Grid adjusted & hoist returned to operation @645p.

PLC processor card failed on the production hoist taking it out of service.

Hoist went into manual and could not be operated. Processor card lost program memory.

At 2:20pm 2 EE's heard a fall in a bermed off notch of U63A H crosscut. GF investigated and reported at 2:50pm that it was at or above the anchor zone. Incident immediately reported to MSHA. Area bermed off. Investigation determined adjacent reliever had not been shot to desired depth thus causing high stress to the area.

Service hoist went down at 4:15 am. PLC processor card failed. Processor needed to be replaced and software reinstalled.

At shift change the service hoist went down no personnel were in the mine. The drive control power and the track limit switch in the mine were repaired and the hoist was put back into operation

While bolting in U8 E tunnel 53 panel a small pocket of methane was breached and bled out within 20 minutes highest reading obtained was .9 percent.

Shaft conveyance was being lowered into the mine, transporting personnel. A sound was heard which was reported to the shaft crew supervisor. A guide wear plate caught the upper lip of the steel shaft guide which rolled back and peeled off, approx. 6""X6"" piece. This needed to be repaired before the shaft could be returned to operation. The mine was evacuated during the repairs.

Concrete rubble was observed on top of the service skip by DMC as they were preparing to begin the day's work in the shaft. Concrete from the shaft liner broke free and contacted the bonnet of the service hoist causing minimal damage.

Roll back fault occurred in the service hoist system. Hoist was reset and all checks were done. Hoist was placed back into service.

During a routine test trip the brakes set and would not release because the system could not build up the required pressure. Through investigation it was determined that the relief (pilot) valve had failed due to contaminates within the oil. Valve replaced, and oil samples will be taken regularly.

In the #3 shaft near the 900 ft range, a torch was being used to remove old guides in preparation to install new. During this process a piece hot slag fell from the work area and lit a known methane bleeder. A sample of the gas was taken for analysis, and a permanent solution is currently be devised to prevent reoccurrance.

Hoist Power feed failed at the transformer controlled by Cleveland Public Power. Feed was then repaired by CPP.

At 8:38am the #3 hoist tripped out due to a drive fault alarm with shaft crew personnel on work deck.9:01 am evacuation initiated and MSHA notified.9:58am all UG employees out of the mine. Shaft crew employees lowered to mine landing at 10:35am. Rebooted TBR PLCs. Shaft Crew brought out in inspection speed. Shaft crew out of the mine at 11:25am.

At 9:45 #3 hoist displayed encoder fault causing hoist to trip out.10:00pm MSHA notified. Co. contacted to troubleshoot issue.Hoist reset,test trips ran,hoist functioned properly,decision made to bring crews out via #3 hoist.All crews out of mine @ 11:48pm.MSHA notified apx.11:55pm. Fault caused by loose connection in the PLC rack.Connection secured, multiple test trips were ran.

Around 0605 #3 hoist kicked out at 200' from the collar. Reset hoist brought crew to surface. MSHA Notified 0614, began evac out #1 hoist. All crews out by 0730. The set screw of the encoder on the hoist drum shaft had become loose. Set screw was tightened, the system reset, and test trips ran. All personnel allowed to return to the mine and MSHA notified at 0800.

The voltage regulation transformer for the production hoist control circuit had and internal problem that would not allow it to provide full voltage to the system & a brake solenoid coil connector shorted internally and needed replaced.Both issues were evaluated and corrected.

Power was lost to the entire facility due to an accidental trip by Cleveland Public Power. CPP was contacted and the power to the site was restored.

Around 10:55am the hoist operator noticed a crack in the main block of the HPU for the #1 Hoist. Maintenance called to replace block valve. MSHA Notified at 11:25am. No need for evacuation, #2 & # 3 Hoists were still operational. Block valve replaced, test trip ran and #1 Hoist back up at 12:15pm. MSHA notified of corrective actions at 12:15 PM. (Incident # 1-101114264)

At 7:10am the brakes on #3 hoist failed to release. After troubleshooting for 20 minutes (7:30am) the call was made to evacuate out #1 hoist. MSHA was notified at 7:40am. Troubleshot from 9:30-11:45am. E-stop had gone bad causing the brakes to not release. E-stop was changed out and a test trip was ran. #3 back up by 12:10pm. MSHA Notified of corrective action at 12:45pm.

During motion on lower a vertical bent section, injured worked contacted the edge of an exposed angle iron. Injured worker received a laceration on his left forearm.

Miner had his finger smashed by a bolt driven out of a guide and pinching his finger against the shaft wall.

While attempting to shift approach rail away from the #6 scale rail, the joint bolts were removed and a steel wedge was driven into the gap to force joints to tighten the gap that opened up in the joint. The new bolts were installed and the wedge was hit with a 10-lb. sledge hammer. The wedge jumped out and flew into EE's leg causing the injury to occur.

The hand brake of a rail car was stuck so the employee tried to jerk the wheel, it did not move and he felt pain in his left shoulder. The employee was diagnosed with a minor tear in the left shoulder. No work restrictions were given and the employee was prescribed physical therapy.

While employees were hoisting a piece of steel which had been removed from the S1 Screen, the weld broke on the pick point allowing the piece of steel to fall, ricochet off the screen and strike the EE knocking him to the floor. This impact caused bruising to the upper thigh, minor laceration to the back of head, and minor fracture to the EE's foot.