Digging a pool? Heck, you're doing archaeology now! Never know what you'll find.
If it is a nice find, you might even want to tell the local paper. Then you'll have to say something like, "Its probably (opinion) an arrowhead!"
;-)
Thankfully, all they've found is dirt. If they hit rock,
the price would escalate and I'd be reconsidering why
I decided to do this.
Have a great one! ampu