I want to know this too. I have a 10-week old Black Copper Maran that's 5 weeks older than the rest of the flock. I thought I had 11 pullets, but one of the Starlight Green Eggers turned out to be a roo. There's been a bit of a power struggle between them, but I think the bigger Maran is winning...
My Black Copper Maran is only 10 weeks old and he's already establishing order over 10 pullets. He just started letting out a hoarse little crow (his wattles aren't fully formed). He pecks at the girls to alert them to go in the coop at dusk. He waits for all of them to roost while he checks...
I think the idea is that because they can't digest yogurt properly, it makes them vomit. Kinda like ipecac syrup is used to make a human throw up a toxic substance.
Mine is closer (maybe 50 ft?), but my well is 450' deep and the water runs off on the opposite side downhill where the septic field drains. The grade of the land and natural runoff is probably a factor to consider. When it rains hard, does the water drain toward or away from the well?