Located a mill that was in operation from 1890-1908 and would like to try to find the dump. Do you guys find anything at old mills? Where would they put the dump? Thanks.
Mills are fantastic for detecting...but from what I understand not all to great for bottle digging. I wouldn't completely count it out though. Give it a whirl and see what you find. The other thing that might be better for bottles, is if the owner of the mill lived close, his/her dump or cellar hole might be more productive...
That being said, I think your best bet with mills is coins, buttons, buckles and relics, especially if it was a textile mill at any point. People used to sell their old clothes to textile mills (they used to recycle the cotton and wool) and their buttons end up all over the place near them. On top of that because there is business going on, so the frequency of visitors was higher than a place like an old homestead (i.e.; there's going to be more lost change).
I wouldn't have too much faith in it producing too many bottles. There's going to be a ton of iron trash, but they did business there so there should be lots of coins. Get out the detector and go dirt fishin.