Hoptal :(

If that's a UXO, I'm actually a little surprised it would be the police on the scene, rather than the army.
- Can't talk for UK, but in Germany there's a service by the government for cases just like that. No army or stuff, just the Kampfmittelbeseitigungsdienst.
  E: "just" at the wrong place
  
  gesundheit
  
  If I own it, does it become Mein Kampfmittelbeseitigungsdienst?
  
  It is a little bit more complex: those guys from the explosive ordnance disposal service are actually only there for ammunition which was used until 1945 or the end of the second world war. Every ammunition after that time falls in the scope of responsibilities of the German armed forces.
  So yeah in total, we technically have two services in the public sector which could handle this stuff :)
- There's 1,000 jokes that can be made in sure, but in the US I once found a grenade while magnet fishing and called a guy my parents know who is a cop. The moment I realized what it was, I told my friend to run to the end of the bridge, and I gently laid it on the pile of rope I was using.
  They have a whole bomb squad that's about 30 minutes away at full speed, and they rolled up with their trailer, a guy in a suit came over to the bridge and placed it in a box, put the box in the trailer, and one dull THUNK later all I had to do was sign a paper saying this is where I found it.
  I specifically called my parents friend rather than 911 because I had read too many accounts of cops showing up and attempting to arrest the magnet fisher for any number of reasons.
  UXO is no fucking joke, don't for a second think you can handle it without training. You really have no idea what explosive compound they used or what it's stability level is after being exposed to the elements.
  
  Why wouldn't you have just loaded it into the transporter buffer and then wiped the pattern (or beamed it harmlessly into space), Mr O'Brien?
- Cops can handle the perimeter. You only need army EOD if local cops don't have a unit.
  
  Around here, they've got one among them on a good day.
- Well, I imagine on nearly every place, the police would arrive before the army.
- Police secure it before the army arrives.

It's an artillery shell and it looks used up from the primer pin
https://forum.cartridgecollectors.org/t/brass-3-5-x-12-tall-ammo-shell/33883/16
- No. It's a water pump. He says it right in the post!
  
  Plot twist : it's a shell casing used to house a water pump.

Somebody left that silly little guy there...

Interestingly enough, I haven't seen one of those unexploded ordnance pamphlets since I was a kid, they used to give those to everyone in my country.
Guess WWII was a long time ago and people have done a lot of metal detecting over the last few decades.

That would be an addition to my collection most likely, i got a load of ww2 shells, one nearly 3 feet tall with the pin intact.
I never get what type of people report like found treasure and shiz, i'd keep it or sell it to a collector most likely.
- i'd keep it or sell it to a collector most likely.
  Or jump in the air and spread yourself across the scenery if you're one of the 'lucky' ones who finds shell that is still viable.
  
  Happy to hear they haven't changed the standard procedure since back in Edmund Blackadder's day.
- Is this a joke? Isn't it incredibly dangerous to fuck with an artillery shell in any way?