Guest bloggers J.A. Villa, Peña Colorada, and Senior MineSight Specialist, R.E. Vivas, Hexagon Mining
Ernesto Vivas
Peña Colorada is one of the largest iron ore operations in Mexico. Located in the state of Colima, Peña Colorada’s operations consist of an open pit mine in Minatitlán and a pellet plant in the port city of Manzanillo.
Despite a production capacity of 4.1 Mt/a (4.5 million stpy) of concentrate per year, Peña Colorada faces declining ore grades. In response, Peña Colorada had to expand production even further. This expansion created challenges that were overcome by the adoption and application of new technology and improvements in geo-modeling, mine planning, and mine operations. The successful implementation of these technologies paid for itself many times over, and has led to significant improvements in production and performance, while lowering the operating costs and reducing the variance between planning and execution.
The first step was to increase the confidence and reliability of the resource model. The Peña Colorada deposit comprises three main structures affected by a moderate fault system. These three structures control the geology in terms of minable material characteristics. The mineral resource model was constructed in two stages: 1) construction of the geological model, and 2) numerical modeling of attributes.
Construction of the geological model involves the processing of the drilling campaign, taking into account the minimum scale of geological interpretation and the construction of surrounding solids. The drilling campaign was processed through the use of MineSight Compass, MineSight Torque (tag mineable tool) and MineSight 3D (assay interval editing) tools.
Model views in Hexagon Mining’s MineSight 3D
The geological envelopes were constructed as geometric solids using MineSight Implicit Modeler to accurately characterize the geological contacts. The numerical modeling of attributes comprises the estimation of grades by localized ordinary kriging. Two sectional block model views in MineSight 3D, along with the pit designs and geologic solids are shown left.
Once the block model was completed, new optimization studies were evaluated with MineSight Economic Planner (MSEP) and new production schedules were completed with MineSight Schedule Optimizer, (MSSO) which improved many aspects of the mine plan. For example, MSSO was used to evaluate and optimize the dump discharge plan.
The results of the optimization generated a plan with less stripping required in the earlier periods and a combination of short and long dumps, which balanced the truck hours over the life of the schedule and actually reduced the number of trucks required. The estimated gains from this optimization study amounted to approximately $35 million in project value.
Likewise, MSSO was used to evaluate the expansion project and the acquisition of bigger shovels (P&H 4100 XPC) and bigger trucks, (CAT 789C & 793F). Mine expansion projects cost hundreds, if not billions of dollars. Investing in MSSO is easy to justify since it can guide important capital investment decisions and it costs less than the tires of an off-highway haul truck.
Mining equipment at a working bench
Additionally, new geotechnical studies were prepared, which provided new guidelines for pit slope design. New technology was implemented to monitor ground movement and slope stability.
Peña Colorada implemented Hexagon Mining’s fleet management system to monitor the operation and ensure plan execution and compliance, thus capturing in the field the value of the project as forecasted in the mine plan. However, there is always a variance between plan and reality. This has been significantly reduced with the adoption of best-in-class mine planning software and fleet management system.
For example, before the FMS implementation the designed blasthole collars for the production drills had to be staked out by surveyors. However, during the rainy season, the weather would delay the surveyors and consequently delay the drills, which hurt production. After the implementation of the FMS, the planned/design blastholes are transferred digitally to the drill equipped with high-precision guidance for accurate blasthole location, so there is no need for the surveyors to stake out the collars in the field anymore. Now production stays on track.
The implementation of Hexagon Mining’s mine planning software and fleet management system narrows the chasm between what is and what should be; and helps to not only shape smart change, but also to unlock and realize significant project value.