RE: logistics28 Feb 2021 13:54
I had an interesting discussion the other day whether the vertical shaft will be constructed from the bottom up or downwards.
I've only got experience of going down and the other chap of going up.
When rereading the mining docs application though it reads about sinking the shaft, so it looks like going downwards.
I believe it's the water extraction that has decided this, there are 3 aquifers to get through and need draining before recommencing the shaft.
One of the diagrams shows numerous drill holes sent down to test the water table. These will probably used to drain the aquifers as the shaft goes down.
If you draw water out of the shaft this will have the effect of drawing water towards the shaft. Better to pump from surrounding holes to draw water away from the shaft.
The box cut base is founded through the first aquifer and I think is 5m into it. The rock from the aquifer is being used for the roads, being saline I think is the reason for the roads looking whiteish.
The water from the top 2 aquifers is suitable for reverse osmosis to make it potable, but the lower one at the base of the Decline is highly saline and will be sent to the evaporation ponds