Explore practical alternatives to traditional pushbacks in open pit mine planning - from satellite pits and open pit to underground transitions to autonomous mining equipment for constrained mining areas.
Video transcription
What Is the Purpose of a Pushback?
The pushback concept is designed to bring more resources or reserves into the mine plan. But there are situations where a traditional pushback may not be the best option. Here are several alternatives worth evaluating during your scenario analysis.
Satellite Pits as an Alternative to Pushbacks
The first option is to look at whether you want to create a satellite pit. Creating satellite pits or smaller pit units within or around the main existing pit can be a significant advantage.
However, when you create a new pit, you are limited in terms of the depth you can reach and the slope angles you can achieve. So in your scenario analysis, or when creating planning options, you need to check whether satellite pits are a viable path - or whether the constraints outweigh the benefits.
Transitioning from Open Pit to Underground Mining
The second alternative is to evaluate whether you should switch from open pit or surface mining to underground. You want to assess whether it makes sense to develop a small underground operation within the area - usually using caving methods.
Since you already have the existing pit, the question becomes: can we drive a decline and extract the mineral using underground methods? This is a well-established alternative to expanding the pit footprint through pushbacks.
Robotics and Autonomous Mining in Constrained Areas
In recent times, the industry is increasingly looking at robotics and automation. Pushbacks often come with limited formation and limited working areas, so the question is whether automation can help overcome these constraints.
You can automate the drilling, automate the loading, and automate the hauling. By employing robotics in constrained areas, you create a viable alternative to the traditional pushback approach where working space is limited.
Equipment Sizing and Contract Mining Considerations
There is a real-world example where a pushback project did not properly consider these factors. After blasting, the operation was unable to go back and load the material efficiently. They had to bring in contract mining and reduce the size of their trucks and loaders - because the mining width was not large enough for standard fleet equipment.
Using smaller mining equipment to handle blasted material in tight working areas is a practical reality when pushback constraints are not fully accounted for during the planning stage.
Key Takeaways
These are some of the key alternatives that mine planners can leverage when evaluating whether to move away from a traditional pushback: satellite pits, underground transitions, autonomous mining, and right-sized equipment strategies. Each option should be evaluated within the broader scenario analysis framework during strategic mine planning.