A well monster lives in my backyard.....

I came upon a very small hole in the ground several weeks ago. I thought it might have been a gopher hole, or that it belonged to some small such creature.

After about a week it seemed to grow just a bit larger, the ground around it had become sunken in and curiousity got the best of me. I was a bit apprehensive about putting my hand into the hole so instead I used a piece of wood (see pic). One after the other dropped down into the hole. Five pieces, six, seven pieces... all about the same length.
All sorts of ideas started percolating in my fearful brain, what the heck? Was it an old outhouse hole? A giant snake hole? Was there something incredibly hideous living in that hole? A well monster! It had to be! After another five or six pieces of wood had failed to reach bottom, I decided that it was time to seek help/advice.

I tried to obtain an As Built card from the town hall but all it showed was the septic in the front yard dated 1993. The house was built in 1930! No records. No permits had been required back then. So was it a well, a septic, or a passage to the center of the earth? The next step... to dig and discover!

As the digging progressed it became clear that whatever it was, it had been capped with cement and that the cap had cracked in half.

The best guess was it is an old leech pit, but it could have had a well underneath. Regardless, I'm gonna need of a whole lotta dirt to bury this well monster. A whole YARD of dirt. Good grief!