Re: met Dave today - Underground Operation
in response to
by
posted on
Jan 09, 2014 11:51AM
Thanks rst.
That makes sense...going after the HGZ first to generate some cash...and do the open pit later. People have similar facilities, e.g. in Australia, that have large portals and ramps for trucks to go in and out. In some facilities, they also include the processing and waste facilities underground as well (just like NOT in its Ni mine proposal).
Depending on the orientation of the deposit the underground mine designs would be different. For vertical and deep deposits, it may be advantageous to sink a shaft with multi-level spiral ramps. However, for a horizontal orientation like the HGZ in Borden, multi level ramps may probably not needed...Instead, a few levels (2, 3?) would do. Imagine extracing a hot dog shape deposit (wienner inside wrapped around by a bun...with mustard and relish, etc ?). One could extract this by entering the ore body from the side, or from the bottom using block-caving techniques. Since I am no mining expert, I would leave it for Dave to make that decision.
In the analogy above, the wiener represents the high-grade core (> 3gpt) and the hotdog bun represents the lower grades. However, from the data we have seen to-date, the deposit appear to have a cross-section like that of a cuttlefish, see below (if link does not work, you can always Google "cuttlefish").
The core (>3gpt) would be the mantle/body of the cuttle fish, the frills/fins could represent the lower grades. You may need to line up a bunch of cuttlefish, heads to tails, to make it look like an elongated Borden deposit.
Just some analogies for visualization purposes (and amusement?).
Cheers,
goldhunter