My well is, I think, 10 inches and they went down 100 ft, hit a teacup full of water, and then called it quits. That was my 3rd attempt and I was tickled to get any water at all. It started out with 1/10 gpm but later improved to 1/2 gpm which I capture in a 2,500 gallon tank. Yeah, they pumped some water down in there to cool the bit and soften the soils. It certainly wouldn't have been enough to use on a pond. Also, they drilled through some rocks and some sand. Useless stuff.
