Hello Peter
Yes, I do know people who have been there. It is a very large lake, and like many up here, it is part of a vast system of interconnected lakes, the largest, (Courageous Lake, McKay Lake, Almer Lake, Clinton-Colden Lake, Artillery Lake) are all interlinked and drain into the East Arm of Great Slave Lake. Most of the other major lakes in the Slave Craton (Lac de Gras, Point Lake, Takjjuq Lake, Contwoyto Lake)drain either into the Coppermine River system or the Burnside River system both of which run into the Arctic Ocean.
The actual size of Back Lake, give or take, is about 18km long and Munn Lake is about half that size +/-.
It is deep in some areas and shallow in others. The environmental lobby has only modest influence in the NWT and draining it would not be that expensive in relative terms, but the real power lies with the land claimants and Federal Government. I doubt either Federal Fisheries, DIAND, the affected Bands, or the GNWT would seriously consider any proposal that would completely drain it, or any lake of significance.
Aber's numbers could perhaps be used as a rule of thumb. I believe they are suggesting approximately $60,000,000 to dyke around their five pipes on Lac de Gras which are relatively near to shore and mostly in water no deeper than 20m.
Adits under the lake would probably be driven to bulk sample any potentially economic pipe, so potentiall they would also be available to use as a mine access however, most pipes are enriched near surface. See Abers NR's on 418. Much of the value of many of the pipes is found in the first 150 to 200m. There is also a real concern with rock (kimberlite)integrity as it is more often than not, a consolidated pyroclastic conglomerate.
I would imagine that there would be real mining safety concerns about underground mining (long term) large volumes beneath large lakes. Shotcreating and cut and fill can only deal with so much pressure.
I suspect you will find that the pipes, if they exist, are relatively close to shore so I would not be too concerned from that perspective.
Regards |
