Hi Marcomo, thanx for the invite and intro
For starters, great that Denis "had permission". Personally, that was risky from the git-go. Because to be honest with you, he could just as easily have gotten a "no", when no real rule exists that says such a thing. Ie.: simply because you asked, and simply because whatever desk-bound person you asked had some mental image, or was in a bad mood, etc... you risk a "no". I would have just gone (barring unless it's on obvious sacred historic monument) and never "asked" anyone. I mean, would you have asked if you can fly a frisbee? Then why think you need "permission" to metal detect? (and assuming, of course, you don't intend to leave holes, etc...).
But be that as it may, you asked, and got a "yes". Great. With all due respect to big-cat-daddy, by telling a city or county bureaucrat to put something in writing, is the FASTEST way to get any yes's turned into "no's". Few, if any, rank-&-file type desk-jockys are going to put something legal in writing for you like that. It only conjurs up images of them putting their neck on the line, and simply presumes that something is inherently wrong, or damaging, or illegal, etc... that you needed it in writing, to begin with! For example, if someone came to your door, and asked if they could detect your lawn, you might say "sure, knock yourself out". But if that total stranger then thrusts a legal document in front of you to sign, what is your thoughts then? You'll reconsider this, and figure something must be awry, eh?
But all that aside, this whole episode is only reflective of how next-to-useless "permission" (as if it had been needed) is to begin with. There has been numerous examples/stories like this, of persons going to city or county hall, getting "permission" (to hunt some innocuous place like this). Then when accosted in the park or beach by a busy-body gardener or cop, proudly whips out their "permission". But it gets just as quickly revoked when that busy-body person gets on their cell-phone, calls down to city or county hall, and says something silly like "but he's tearing up the place" or "he's harming the earthworms" or any such thing. And if you debate them, guess who's going to win?
Naturally, having NO "permission ALSO doesn't "solve" this. Granted. But at least you don't preclude yourself from hunting some place where no one would really have ever cared (till you asked).
All I can say is, there is simply no escaping the oddity that our hobby has. It draws the stares of the curious, and does, admittedly, have connotations (that you might leave a mess, or steal the publics cultural resources, etc....). It's gotten to where I only hunt parks at odd times, when no such person's are present. You know, like after 5pm, early AM's, or even at night.
You could certainly go back to the person who gave you "permission", but then the risk becomes, that they might just ..... to avoid hassles, simply say "no detecting" in the face of this beat-cop. Here's what I've done in cases like this (and it's probably controversial): I just go back at a different shift, when I know that particular busy-body is not on-shift. For example: if that happened in the AM, then odds are, their shift is AM's. Simply wait a few weeks, and go again at an evening time. I got flack from a lady-cop once, at a park I'd detected at for 15+ yrs., in a city a few hours from me. Rather than debate her, and since I was done for the day, I just paid lip service and left. Since I don't get to this part of the state that often, it was a long time (6 months?) before I was in that area again. I simply went again (being careful to choose a low traffic time) and ...... that was 7 yrs. ago. I've been back dozens of times and never heard "boo" again.
Anyhow, you say you weren't finding any oldies anyhow, so perhaps it's a non-issue?
