What a real inspection includes
A drive-by opinion is not an inspection. The genuine article involves locating the system, opening and pumping the tank, examining baffles and tank integrity, evaluating distribution boxes and lines, and assessing drainfield function — often with records pulled from the county.
You also come away with a map: where the tank and field actually sit, which matters for everything from future repairs to where you can build that shop.
Why the stakes justify it
Drainfields age out. Tanks crack. Roots invade. Systems installed generations ago may bear little resemblance to their permits, and a failing field discovered after closing is your problem at full price. Discovered during inspection, it is a negotiation: repair, replacement, credit, or reconsideration.
On the McKenzie corridor, where nearly everything outside city limits runs on septic, this inspection is as fundamental as the home inspection itself.
Local rule of thumb: Pumped, scoped, and mapped — accept nothing less before the contingency expires.