Ya know. Given a couple of items that you said you'd found in the junk. It's a pretty good bet that it was at one time airtight enough to hide freshly cooked dope in. and it does go with the whole scenario of the witch's circle.
And just how far is this area from anyone who would notice the fragrance coming off a batch of cookin' meth? Gotta cook the stuff far enough out so nobody smells it. And need safe places to put it before you distribute it.... or in case you get raided.
Way too close to the store and other houses to hide a meth lab.
But you couldn't have gotten anything in or out of it! It was up-side down with no way to open the lid.
But meth lab-wise, I think it is far enough - people get away with it (for a little while) in subdivision garages don't they? - it's a few hundred feet.... the total property size in the fat lines there is 7 acres. The witch's circle is in the red circle there.

- I think you read my (3,400) wrong....I did NOT find Acetone and propane tanks like you might expect if they had left careless waste around from that.... But I don't exclude that they might have done it... related to the barrel or not.