Falls and Loose RockThis page is divided into two sections. The first section deals with common areas where loose rock may be found inside mines. The second section is an introduction to shafts, inclines, winzes and false floors, and what you need to be aware of around these potential dangers.
Most hard-rock mines are solid once you enter the actual host rock beyond the topsoil and loose material near the surface. However, mines often cut through unstable soil before they enter the host rock. This is why it is common to find mines with timbered entrances. Mine entrances can collapse over time due to slough (loose material) of the top soil, or BLM bulldozing. You may need to clear some of the debris before you can safety enter your mine.
The first step is to assess the condition of the mine from the outside. Examine the portal or entry. Are there potential rocks or dirt that could come down and close you inside? What would it take for that rock or dirt to become dislodged and fall? If you entrance is timbered, assess the timbers. How stable are they, are they rotting and do they need to be replaced? Don’t be afraid to use your rock hammer to hit the timbered portal. If it’s not stable enough to take a hammer hit, you will probably need to shore up your portal.
Once inside the mine keep an eye out for unstable areas. In general mines are relatively stable; they are cut into solid, hard-rock that has survived hundreds of dynamite blasts as miners advanced the workings. Miners didn’t have a death-wish; they made sure that the mines they were working in were stable. Be aware of everything, the ribs (sides of the mine) and the spine (ceiling) and note any areas of concern. Sometimes inside mines you will find stoping or drifts with loose rocks. The loose rock can be pried out with a scaling bar, a commonly used mining tool used to remove loose rock fragments from the ribs and roof of the mine.
Being aware of your surroundings is key to safety inside the mine. Watch out for suspended rock overhead. Watch where you place your hands. Look for evidence of previous rock fall or movement and be aware of unsupported material in areas where there is evidence of previous rock fall or movement. Sometimes ore bins are holding up quite a bit of loose material. Avoid disturbing ore bins, false floors, roof supports or other retention structures. Old timbering can be rotting and no longer able to hold up loose rock. Check the stability of the timbering from a safe distance. If the timbering is not safe, use wood from outside the mine, or make a stop by Home Depot. If you don’t know how to shore up a mine, grab a book and learn. Then go to it.
With casual use mining the main concern you will have is the stability of the rock after removing your ores. Work in small sections. Meticulous work is going to be quality work. Work one small section at a time. A working area of 2-3′ in diameter is ideal. Once you have removed more than 1 cubic foot of rock, use your rock hammer to verify the integrity of the work zone. A solid, stable mine will cause your hammer to “ring” or reverberate. If you hammer makes a dull thud with no reverberation then the cracks and voids between the rocks are absorbing all of that energy, indicating the mine is not that solid.
Shafts and Winzes
Before you enter your mine it’s best to find out as much information about the mine as you can. The easiest mines to work are adits that are cut horizontally into the mountain. Sometimes adits will have false floors that may not be in the best condition. These false floors can cover winzes that descend hundreds of feet into the earth. Watching where you step is key. Rich veins don’t always run horizontally, and sometimes miners will have cut a winze straight down in the middle of a drift to chase the ore body.
Avoid unstable areas around shafts, and winzes and make sure that you are properly secured while working around these features. Avoid disturbing loose rocks or materials near these areas. Avoid traveling over false floors. Be properly secured while working on or near false floors. Never ascend or descend a ladder or structure that you are not convinced is secure. Use proper fall arresting equipment or rope and harness when traversing. Never stand on a platform unless you are convinced it is secure. Wood can easily rot. Be aware of and avoid the numerous trip hazards underground including: loose material, uneven surfaces, protruding fixtures, slopes, water, mud, etc.
Before you enter your mine it’s best to find out as much information about the mine as you can. The easiest mines to work are adits that are cut horizontally into the mountain. Shafts descend down into the earth at all angles up to vertical and require at least two people to safely access and work. To obtain an accurate survey or to extract rich ore, you may need to employ rope work.
Rope work is something that you should be specially trained for. If you haven’t used rope and rope gear underground, obtain training first. Once properly trained always remember to observe the following:
1. Don’t rappel farther down the rope than you can ascend.
Never descend on a rope without proper gear. Hand over hand is not the proper way to traverse a rope. It’s easy to rappell 500′ down into a shaft, however, climbing a rope that distance is a completely different animal. Again, get the proper training!
2. Watch sharp angles and rub points that may damage the rope.
You are working with sharp rock edges. Your rope must always be protected. If the rope is damaged it will not be safe to trust your life to.
3. Use static rope certified for climbing purposes.
Do not use dynamic sport climbing rope or any other kind of rope. Rope found at hardware stores or your local big box store is not designed and certified for this purpose and is not appropriate to use as a lifeline.
4. Redundancy is key.
Always back-up every important piece of gear with another piece of gear and use more than one anchor point when possible. Always use sound judgment. Obtain the proper training for underground rope work and be physically able enough to do the work safely.
The advice regarding safety, found above, does not cover every danger you might encounter in a mine and is not a substitute for sound judgement. We recommend becoming as educated as you can on mine safety. The more you know the better chance you will have of enjoying your mine and extracting the ores without incident.