We are going to re- attempt the salvage of the strongest existing borehole. The slow-down in delivery of water during the ” Covid-19 lock-down” plus the deterioration in the general economic standing of the community, has forced us to address this problem again. The complication that we have been faced with is that the borehole was sabotaged and various items stuffed into it, including a lot of broken glass. Trying to scrape this out inside the borehole casing was an impossible task so we have developed a plan to tackle the salvage in two stages suing a different set of tools.
- Try using an auger to loosen the material and glass and use the tools made before to drag out what the auger does not get, The auger diameter is 100m and the borehole casing 145mm .
- We wish to get down 1 -2 metres and then we will try to use a percussion flat bottomed bailer to remove the rest of the material.
The plan was originally to manufacture an auger to the exact spec of the borehole. However, time permitting this will be a project for another day. (There are some very clever methods of fabricating the auger and these can possibly be used at a later stage as and when we require this technology. It might be particularly useful in a drive on a Urinary diverting toilet). We were fortunate to buy a cheap auger but without the mechanical drive unit. We thus decided on trying to make a manual handle and shaft to drive the auger.
The initial plan was to use 8mm “council” drain cleaning rods but we decided this may not allow for the necessary force to be applied. Furthermore as they rods did not have to bend we, turned to square tubing instead as we had a small supply on hand.
Step one was to find a heavy duty mild steel bolt that would fit into the auger shaft. We cut the head off this bolt, drilled a hole to fit the safety pin and then welded it to 200mm of 16×16 square tubing. A second 8mm hole through the end of the shaft allows it to attach to the longer extension shaft which is 25x 25 square tubing. We made this shaft only 900 long as this together with the auger would give us sufficient depth to test. However, it is very easy to lengthen this by replacing it with a longer piece. We then fashioned a handle by welding 200mm of 16×16 square tubing to an 800mm 25mm diameter pipe as a T drive unit. A quick undercoating and then a spray paint and the borehole salvage tool is now ready for testing