In 2002 - at the time the agreement was signed, i think that Teck would have known or would have reasonably suspected a few things about the project just by its familiarity with the property.
SC has been explored since the 60's, maybe earlier. A lot of drilling occured in the 70's. A lot of those old drills had good grades at depth but - for whatever reason - didn't do much or any drilling deeper than 300m. It could have been the going thought about economic it was to go past a certain depth past X.
The real point is that they would have suspected that any project there would be in the $1-3B range given the general idea that this was a large low grade poryphry deposit in a remote mountain setting. There is no getting away from that.
As far as the fish and enviro footprint... I think that repeated field work on the project woudl have given them a general idea of where there were fish (people were fishing Mess Lake in the next valley for years) and where there were not - like Schaft Creek. Take a look at the images below...
So I think Teck would have had a very general idea that there wasn't a big enviro risk with the project but that the info required for the permit requirements and EA would lead them to any unfound issues like the last 3-eyed fish on earth ;)
For permiting, legal and other DD reasons, CUU still had to survey, inventory, map and monitor all these enviro resources and conditions - to document them for the EA and assist planning the general mine footprint. IMHO They have doen an excellent job at delivering a thorough ecological assessment of this project. http://www.copperfoxmetals.com/s/SchaftCreek.asp?ReportID=209031
Below a snip from a previous post about Schaft Creek and its lack of fish habitat potential:
No fish in Schaft Creek and no fish habitat till Mess Creek and then the Stikine.
This image shows how 'chocolate' Schaft creek can look. The muddy water is coming out of the Hickman valley - probably from the glacier shown in the bottom image.
http://www.flickr.com/photos/unukriverpost/6299421881/in/photostream/lightbox/

http://www.flickr.com/photos/unukriverpost/6299957166/in/photostream/lightbox/

http://www.flickr.com/photos/unukriverpost/6299950534/in/photostream/lightbox/

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