Waste/Sewage System

Oklahoma has statewide regulations relating to septic systems. You'll need to get a permit from the state, have some soil tests done, have various inspections and sign-offs, etc. Professional design is likely a practical necessity, if not actually mandatory. I don't know exactly how things run there, but here in Vermont you're generally talking about tens of thousands of dollars. Two 55 gallon drums and a drain field would definitely not be an acceptable here. Fines and penalties for non-compliance are significant, too.

See Title 252 of the Oklahoma Administrative Code Chapter 641, “Individual and Small Public On-Site Treatment Systems” for the details.