Hardrock Mine Orientation

Underground Mining for Professionals

This is the same sort of guide that we use for new miners however we have added a few more things for you to be looking out for. Now we all know that as a professional your knowledge on subjects will be high. This is a guide for understanding how the mine works to its best speed and efficiency for both safety and profit.

This means obtaining an efficiency level that makes it the safest and most productive minesite by using both the miners and professionals skills to the best of their ability. So let’s start.

Once the pit has reached its maximum depth the underground mining starts. This is when we start a tunnel called a “decline” the entrance is called the “portal” and goes at 1 in 7 down. That is, for every 7 metres across we go 1 metre down.

We then access the mine through the portal using approved light and heavy vehicles. Once the rock is broken it is loaded onto the back of a truck and brought to the surface where it can be milled and processed. An underground mine can also be on flat ground, these are called shaft mines. If you end up working in one of these mines you will have to go to work in the “cage”, which is lowered into the ground like a lift in a building. Once the miners are at work they use this same shaft to extract the rock. Below is a picture of a “head frame” this is the structure that holds the cage as it’s lowered.

A decline mine

Once the open pit has reached the point where too much waste rock needs to be removed the normal practice is to send the mine underground if the ore body is still going deeper. When someone says that the ore body is open at depth this means that the ore body has been drilled (explored) as deep as possible and the ore body is still going strong. The Portal (entrance to the mine) is normally located two or 3 benches above the bottom of the pit so there can be no inrush of water. Every underground mine needs 2 forms of egress (way in and out), this takes the form of the main decline (portal) and an escape way.