As the visitor can see from this website, I have been involved in quite a few projects, these mainly involve actual mining. However, this is in the sense of sinking and driving through areas of collapse in order to reach unexplored workings, rather than mining for the extraction of ore.

On this page I will set out what I consider to be best practices in this respect.

Sinking

If an internal winze or surface shaft has to be cleared, the technique will depend on the nature of the shaft itself. If is of a manageable size and sunk through solid rock, obvious best practice will be to clear it out completely raising muck by any convenient means. If finances will stand it there are portable petrol driven winding engines manufactures in the USA that can be deployed, coupled with a home made kibble of suitable size. If the sinking is through a collapsed stope, obviously timberwork will have to be employed, so refer to my section on timbering.

Be aware that there are certain safety issues relative to sinking. If its a vertical shaft there will need to be a proper risk assessment made that includes securing anyone working at top drawing in filled kibbles for emptying. Best practice is a trapdoor with a slot for the winding rope that will fall closed as soon as the kibble is clear. The idea is to prevent the off loader from falling into the shaft. At least they should be wearing a harness and secured with a cows tail.

Driving

This refers to the driving of a roadway, usually in timber using a technique known as spiling, through collapsed ground.

Spiling refers to the driving in of forepoles and then mucking out and timbering below them. Forepoles can be scaffolding poles, or old drill steels. Although scaffold tubes are more rigid old drill steels have the advantage of being drivable through solid boulders with a sledgehammer, at least in mudstone areas, the boulder usually splits. If scaffold tubes are being used there is a trick of allowing the boulder to fall just enough to get the steel over the top of it, but not enough to let a huge pile of debris come down that will take days to muck out.

Most collapses are in stoped areas, but can also occur in bad ground. If you are following a stope, or a passage that follows the cleavage of the bedding plane, always drive on the hanging wall side. Its unlikely that you will be driving the full width of the stope, so although the footwall can provide support for cross timbers on that side, the disadvantages outweigh this. For one thing your passage will be unnecessarily wide at top due to the underlie, thus requiring heavier timbers and more muck to be removed. Also, the advantage of keeping to the hanging side is that the fall material will form a natural arch into the hanging above your timberwork. Remember that if you were to build a wall a few feet away from the hanging, proceeding vertically upwards your wall would eventually meet the hanging. Of course, in the event that the stope is narrow, you could muck out to the full width and put in your timbers wedged into and seated on the cheeks, just like the old man did.

The logistics of mucking out can be done according to the situation, varying from little skips made up from old 5 gallon containers with steel plates screwed to the bottom to make the thing last, up to wheelbarrows are even home made trucks running on wooden rails, or even the original mine rails if still there. You might even find an original truck in running order somewhere in the mine.

I have found that the best working height is compromise between full walking height and a crawl. The crawl type 'cavers' digs often fail when they come up against a big boulder that it is impossible to get out, while too much height makes more work. I always aim for about 5 feet, if the height falls below 4 feet I try to restore height if possible. Its possible for the average person to move through passage just under 4 feet and stay on ones feet, although you may come out like a human question mark!

Forpoles should always be driven up a slight angle so that by the time you come to put in another set the level will have increased in height and you will not loose the working height which can be fatal.

Timbering

Where you obtain your timber is your business, but a lot of mines are on Forestry land, say no more. But avoid like the plague untreated timber. Take the home with you, strip off the bark, and dose it with preservative. Untreated pine will never last more than about 20 years, sometimes as little as 3 years. Certain conditions and air currents will exacerbate timber decay in way that has to be seen to be believed. Upcast shafts in working mines are notorious for this, in the later days of Cornish mining steel was extensively used because of this problem.

Wherever possible cross members should be shaped with 'flats' cut into the ends to prevent the uprights being pushed inward and to provide a flat pad for the load. As an alternative you can put in an extra cross piece between the uprights as a spreader. Try to avoid round timber cross pieces that have not had flats cut into them, the load will bear on a small area that will become compressed allowing the timberwork to loosen. A workaround to this is to put in a couple of wedges as shown in the diagram. Use wedges as much as possible to fill gaps and keep everything tight. A good source of these is anywhere where the forestry have erected new fences, they cut and trim pieces to fit and just discard the cut offs on the ground, also remember its treated timber.

As you muck out try to separate solid rocks from loose attle, you will need the latter for your packwalls. If your drive is following the hanging at a width narrower than the original stope, you will need to fill in between your footwall side uprights with packwall. If there is a lack of solid rock and its all basically attle, fill sandbags with it and use these. They can be used to construct wall packs and roof packs, alternatively, use old plastic fertiliser bags off the farmers.

Above shows the method of spiling with waste rock being used to fill the gaps between the side timbers.

If the rock is of a solid nature but no suitable recess or ledge to wedge a timber in you might consider drilling the rock and bolting in a section of angle iron. I don't like this and the old man would shudder at it. Never load onto the rock face always into it.

Ladder construction may well come into play particularly if you are sinking instead of driving. Try to avoid old builders ladders or wooden household ladders as they wont last 5 minutes. Proper mine ladders are easily constructed from 4 * 2 inch carcasing timber and steel bar stock or even conduit pipe. They can be assembled underground if required, and are surprisingly light in weight unless they become soaked. If your ladder assembles loose for some reason use a length of all thread and nuts and washers passing through a rung made from conduit pipe.

The use of wedges. These come in everywhere to keep things tight and distribute the load.

Wedges put in by the 'old man', Level Fawr skipway timbers, Cwmystwyth

Below: My roadway in the Altycrib mine at Talybont. Note the spreader below the cross piece and side packs between the timber uprights on the left. The hanging wall of the lode is on the right. On the floor is a drill steel to be deployed as a fore pole.