Yes. There is no one around regulating anything at all.
You might want to check with Wayne National Forrest staff since it is very close to the state park and when it comes to metal detecting they can be a little funny. But they don't have a ranger station at the tunnel. Its hard to say what all you might find since it was a party spot for high school kids and college students for decades. If you can't detect at the tunnel or trail area you might be able to detect along Raccoon Creek. There were many swimming holes along the creek over the years. So you could probably find a ton of stuff along there. Good luck with your metal detecting and with any luck you will find some cool stuff out there.
Yes there is no monerting
Yes you can. I even seen someone at the lake metal detecting
Off trail I doubt you will be bothered even in trail. People come from NY to bow hunt and gun hunt so be safe
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