WAS STANDING ON A SUPPLY CAR HOLDING ONTO SOME 4'X4' PIECES OF 3/4"" PLYWOOD AS A OPERATOR WHO WAS LOADING THE MATERIAL WITH A FORKLIFT BACKED AWAY. AT THIS TIME THE SLOPE HOIST OPERATOR SAW ANOTHER EE STANDING AT THE END OF THE SUPPLY TRIP THAT WAS TO BE DROPPED DOWN THE SLOPE. THINKING THIS EE WAS GOING TO CUT THE SUPPLY TRIP LOOSEFROM THE CAR INJ WAS ON PULLED THE TRAP A FEW IN