panning is considered an existing activity and is allowed on all rivers in Oregon. (respect private property/claims)
several rivers are hands and pans only no tools for digging. prospecting/panning is not mining.
the Wild ans Scenic rivers closed to "recreational mining"
https://www.oregon.gov/dsl/WW/Documents/RiversClosedPlacerMining.pdf
other non-motorized like sluicing fall under discharge from a point source.
so they want you to have a copy of the 700pm close by, just print it out.
https://www.oregon.gov/deq/FilterPermitsDocs/700pmPermit.pdf
the other consideration is removal/fill, salmon habitat (ESH) "waters of the state" means below the high water line.
for all streams there is a non-motorized exemption of one cubic yard per spot, five CY per stream per year.
over that in ESH they want you to have the General authorization for digging up to 25cy,
other non-ESH streams its 50cy before needing a removal/fill or joint USACE 404 permit/
https://www.oregon.gov/dsl/WW/Pages/Mining.aspx
off-stream they want you to have a water pollution control facility permit (WPDF 600) but haven't issued any new ones since 2016
people that had them are administratively extended, BLM/FS require one for a PoO or get a surface mining permit from DOGAMI ($$$)
for the weekend miner LEO's don't harass people like they used to for them, IMHO if they don't issue a permit you don't need one...
If you want to say you made an effort to comply you could download a copy if asked just say its administratively extended.
https://olis.leg.state.or.us/liz/2017R1/Downloads/CommitteeMeetingDocument/96041