Are you familiar with GIS? If so, you can download and view all current property ownership in Okanogan county by getting the parcel data from here:http://www.okanogancounty.org/planning/data.htm
If you don't have any GIS software installed on your computer then I suggest you get the free dlgv32 Pro software here:http://mcmcweb.er.usgs.gov/drc/dlgv32pro/
You can also use ArcExplorer as the Okanogan GIS web site suggests, but the USGS software I recommended is much better and is still being developed. Just download the parcel data as a zip file and dlgv32 Pro will open it still zipped up and display it correctly without any difficulty.
Or, if you don't want to become a GIS expert, give me an exact township range and quarter quarter section location for the mine and I will look it up for you.