Kierens Creek It's wide in the Kierens/Norlartic mines area, probably more like a slough prior to the lake. As the veins dip under the creek/slough, they should be drilled from the north, hence the need to cross the creek. The North zone is tied to the Norlartic mine shaft with two underground drifts. The North-North zone is further to the north and could be tied in to the Norlartic shaft drifts.
I believe what Aurizon is struggling with is several obstacles:
1) High strip ratio on Marban--by my calculation up to 7:1.
2) The creek/slough near the Kierens/Norlartic/North zones making open pitting difficult. It is not impossible to reroute a creek, but permitting and cost will be increased.
3) Probable high strip ratio of Kierens/Norlartic/North zones if open pitted.
4) The high strip ratio of most defined orebodies on the Marban block/versus forgetting the lower grades and just underground mining the higher grades, which are low for an underground mine.
5) Looking for UG higher grade ore to push up the overall milled grade, subject to metallurgy/recovery.
Aurizon is having the same issue with their Joanna project.