Out in Wentzville, or are you working in the Chesterfield Valley?
When I worked construction for a small builder before going back to school, I work on a $900,000 house off Wildhorse Creek Rd. I think the builder just put a normal air conditioner but he had to put in a septic system with about a 1/4 acre leech field.
But yeah. Lot of rich dirt and rock....most is probably limestone so I'd be careful about it, because of acidity changes. Also took out a ton of trees, which just got chipper-ed.
So you might consider that option too....free mulch anyone.
Faith is silly. It demands blind obedience to things you have every right to question.