Thanks for the response, Matt . . . yes, I wish I had had them put something about the sand in writing . . . and, yes, the owner of the pool store SHOULD take responsibility (he didn't just recommend these guys, he hired and scheduled them). But this whole thing is making me so angry that, for my sanity, I just need it fixed now and I really don't care if I have to pay for a new liner and the labor to replace the sand. It is pretty clear to me that convincing the owner of the pool store that he is responsible is going to take some serious time and effort and major stress and I just can't spare it right now. Also, the construction of the deck that will go around the pool is on hold until it's fixed. Very irritating.