# Distribution of Operating Costs Along the Value Chain of an Open-Pit Copper Mine
## 1 Introduction
These studies aimed to optimize transport systems to improve efficiency and minimize operating costs. Furthermore, [PERSON] and [PERSON] [22] developed a cost model to minimize total mining costs for bench production in open-pit coal mines. Given their impact on all mining activities, they incorporated fragmentation size and blast-hole diameter as key decision variables and used an evolutionary algorithm to optimize operation costs. [PERSON] et al. [23] developed an econometric model for estimating total operating cost based on data from 20 existing open-pit coal mines in Australia. The model focused on four independent variables, including deposit average thickness, stripping ratio, capital cost, and daily production rate, with operating cost as the dependent variable. The results indicated that capital cost and production rate have a negative effect on operating cost, while deposit average thickness and stripping ratio have a positive effect. In their study, [PERSON] et al. [24] performed a pre-feasibility assessment of four processing routes for an open-pit iron mine, employing different technologies with an emphasis on the stages of communiution and classification. Considering CAPEX and OPEX estimates as economic indicators, routes based on High-Pressure Grinding Rolls (HPGRs) and Vertical Roller Mill (VRM) technologies were found to be particularly attractive for the beneficiation of the itabirite iron ore studied. In addition, OPEX estimates were limited to liners, grinding media, and energy consumption. [PERSON] et al. (2015) conducted an economic analysis of a mine-to-crusher model to estimate and minimize operating expenses for a truckless open-pit iron mine. The calibration of this model was based on rock fragmentation from the blasting phase. By considering the structural lithologies of canga and jaspillites, the authors concluded that the 80% passing size (P80) value that minimizes overall operating costs ranges from 0.31 to 0.34 m. [PERSON] et al. (2016) estimated the production costs of an open-pit gold mine with multiple deposits, considering factors such as dilution and losses. They showed that managing ore quality parameters through internal reserves use reduces the operating costs of the processed rock mass across the entire production chain. In an interesting sequence of studies, mining operating costs in Chile, the world's largest copper producer, have been analyzed and reported on. For example, Knights and Oyanader (2017) conducted a maintenance benchmarking study across six open-pit copper mines, with mill capacities ranging from 18,000 t/d to 156,000 t/d. These mines collectively accounted for 58% of Chile's copper production in 2000. The study found that, on average, maintenance costs represented 44% of total mine production costs, including operating and maintenance costs but excluding G&A expenses. [PERSON] (2018) found that declining ore grades in the porphyry copper deposits of northern Chile led to rising mining costs (including cash costs, depreciation, and indirect interest costs) from 1980 to 2015. From 2001 to 2015, concentrator plants saw an 87.1% increase in electricity costs, compared to a 48.1% rise in mining costs. He also presented an index of total unit costs for 2005-2015, including operating, financial, and non-operating expenses, revealing that Escondida had the largest cost increase among the ten largest private mining companies operating in Chile. [PERSON] et al. (2019) conducted a sensitivity analysis of operating costs for an ex-post net present value (NPV) assessment to evaluate the potential impact of efficiency gains from privatizing mining operations (as a hypothetical counterfactual scenario) on nationalized mining operations between 1967 and 2022. The analysis revealed that a reduction in operating costs exceeding 4.5% would lead to a negative NPV, making the counterfactual scenario more advantageous than the base case.