Potato farms near me use both insecticides and herbicides during the growing season, some of which are applied by a crop-dusting plane. I'm assuming just the insecticide is applied by plane, but they don't border my land so I have no info on possible drift damage.
They don't use cover crops here and till the crap out of it, so lots of topsoil blows away in the spring while they're working it. They irrigate every day because the soil can't hold any water.
Here the potatoes are in a rotation along with peas, green beans, cabbage, and sweet corn. They must make a killing as the ones around here have a ton of acres, and the owners have huge, fancy houses.
I'd make sure you know the exact details of the farming practices he intends to use before signing.