Garden to well distance

Not new to gardening but need advice on safe distance of garden placement to my well. Planned position is just uphill from the well. Well is 110' if that matters. I will be using all organic fertilizers obviously but want to be sure the location will keep drinking water safe. Thanks.

I would have no problem planting right up to/over the well.  

In our area you can even graze livestock right around a well,  you just can't have a feedlot there!  I think an organic garden would be perfectly safe.