EVALUATION OF FAILURE IN LIMESTONE PRODUCTION AT PT SEMEN TONASA, PANGKEP REGENCY, SOUTH SULAWESI

The implementation of sustainable mining should be emphasised that sustainable development is, in any case, a continuous handle, and not a transitory under-taking. An effective management strategy requires failure management in order to identify and minimize the effect of the failure. PT Semen Tonasa produces cement made of raw materials such as limestone and clay. Limestone mining in PT Semen Tonasa is done through process such as drilling, blasting, loading, hauling, and crushing. Limestone production report of November 2022 shows that actual production reached 613,809.37 tonnes with production target 645,460 tonnes. This number shows that actual production did not reach the target of November 2022. Detailed evaluation in the mining process is needed to identify failures which responsible to the unattainability of production target. Each of the mining process is simulated using dynamic modelling, in order to predict if the production would reach the target, using current parameters that applies in the field. Simulation results shows that limestone productivity tend to fluctuate for each day, but mostly did not reach the target instead. In order to identify failures, Failure Mode Effect Analysis (FMEA) is done for each mining process in PT Semen Tonasa. This analysis resulted in Risk Priority Number (RPN) that shows which process of mining should be prioritized for improvement. RPN ranking shows that hauling process should be prioritized. Therefore, the improvement plans are calculating optimum number of equipment using the match factor theory, and road geometry planning based on AASHO 1965 standard.