STAGGERED CREW PRODUCTION EVALUATION IN DEEP ORE ZONE UNDERGROUND MINING PT. FREEPORT INDONESIA

To increase production, the Deep Ore Zone (DOZ) mining department has a concept of implementing a staggered crew. A staggered crew is a crew formed specifically to support production activities. To assess the performance of the application of the staggered crew, an evaluation of the factors that influence production activities is carried out. Factors that are subject to evaluation are working time, number of operators, and production capability. The results of evaluating work time (optimum efficiency) for crew I, II, and III showed as follows 29%, 30%, and 28% respectively. Very low efficiency is due to time constraints in operation, which are affected by delay time, idle time, and maintenance time. Average productive work time (work) is 3.26 hours/day, delay time is 3.26 hours/day, idle time is 4.03 hours/day, and maintenance time is 0.53 hours/day. Idle time is the highest time of these four parameters. The results also showed that there were differences in the number of distribution operators, namely Crew I numbered 16 people, crew II numbered 12 people and Crew III numbered 15 people. But the number of operators on each crew is still sufficient to support production activities. The average production is 62.14 tons/hour and 4,784.78 tons/day. So with a production of 62.14 tons/hour and a working time of 11 hours/day, it takes a minimum of 8 dump truck operators to reach a value of 5,468.32 tons/day.