If you review the corp presentation on the Zen web site, Page 8, it gives a great aerial view of the property which to my untrained eye shows no river running throught the drill area, there maybe a river that runs through the property but not where they are now drilling.
And as far as the native issue, I don't believe there is any issues currently. I've read that Zenyatta has in place an agreement that covers the company's activity upto the PEA(?)...so what happens after that, I'm sure that Zen is working on an extension to the agreement.
I also think that Zenyatta has a First nations individual on its board.