Forget calling ether Sheriff's departments as sad to say they will do nothing. to them its a civil mater.
I know as i have been mining out here since 1968.
You may have better help with the BLM LEOs
Citizens arrest and a camera.
If you catch someone actually digging. If not there isn't much you can do.
it is a civil matter BLM lEO doesn't have more power or jurisdiction over a S.O. deputy.
I have caught a guy..with a detector..and parked. report to sheriff. All they can do is warn him.
if you actually catch them digging you can film it. you are the witness so you can arrest.
Even if they leave the sheriff will make an attempt to find them. If they aren't local to the area don't expect much.
Even with a good case and evidence it will still be up to the DA to prosecute. Don't count on that unless it is thousands of dollars in theft that can be proven.
With all the changes in offense status misdemeanor vs. felony. The way they are "decriminalizing" so many offenses in Ca.
Don't expect anyone in law enforcement to get too involved.
There are a lot worse things in Ca. you can get caught red handed for. Yet, barely get a limp handed slap on the wrist.
dealing with highgraders is way at the bottom of the list of things the Sherriffs Office is going to spend time on.
At this point I just try to be as present as possible and hope to run into anyone in person..So, I can take care of it myself.
At the end of the day it's a lot less frustrating ( more satisfying) Than having the S.O. do nothing.