At the town hall held at Tecumseh this exact question was addressed to Scot Honam. It was a couple years ago and I am going from memory but I believe I have the gist of it correct:
Test drilling costs a lot of money and the cost is based on the number of feet you drill. All of the drilling so far has been from ground level because we have no other options. But, for every drill hole we make, we pay for 600 feet of drilling that tells us nothing. We have enough data now to prove that we have an ore body that is big enough and of sufficient grade to make the mine financially feasible. Once we get the mine built we will have a 26 foot diameter shaft that is about 1000 ft deep. We will have people and drilling equipment on site. We can do a lot more test drilling and it will cost us a lot less.
My personal observations:
These drill rigs are not that big. One of them can easily be set up at the BOTTOM of that shaft. According to the BFS they will be drilling a bore down to the end of each stope in order to pump it full of paste after they have mined it. So, they WILL have drilling equipment and the people to run it on site. Most mines do periodic test drilling in order to plan the timing and extent of the mine. They want to know exactly what they are mining before they mine it, not mine it, send it to the surface, and find out later it was real low grade. Competent management spends the amount of money they need to spend to find out what they NEED to know. When a company has very little money (Niocorp at present), they DO NOT spend a bunch of money finding our what they would LIKE to know. We would all like to know how big this ore body really is and what the grade is as you go deeper. I am sure Smith, Honam, etal would too. Businessmen like Mark Smith do not waste money they don't have on things they would like to know, they spend what money they do have on stuff they need to know. The Canadian Gov has fairly strict rules on how you classify the extent of resources (Proven, inferred, etc.). The terms "open at depth" and "open to the NW and SE" mean noting with regards to these rules. They did not have to include these phrases in the feasibility study, but they did. At lest IMHO: the are trying to send a message.
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