EMPLOYEE WAS IN PROCESS OF BEING TRANSPORTED TO HIS WORK LOCATION, PASSENTER ON #8 JEEP AT OR NEAR 112 BLOCK 3 WEST TRACK HAULAGE. OPERATOR WAS UNABLE TO MAINTAIN CONTROL OF VEHICLE, DUE TO DR IVE CHAIN DISENGAGING FROM SPROCKET. EMPLOYEE JUMPED FROM VEHICLE, LANDING ON HIS W-65 RESCUER, PAIN RIGHT HIP AND RIB AREA.