I don’t know why the county suddenly needs a site plan with the cabin, septic, and drain field location. The cabin was originally a 20 x 24 ft box built in 1967. We bought it in 2002 and it’s been thru several major remodels since then, none of which required any thing like this. The latest remodel is just some work on a bathroom, moving a wall out by 4 ft. If they don’t accept what I put together, I’ll probably need to hire a surveyor $$$.
Since I am learning Sketchup, I decided to go ahead and try to draw it. The cabin drawing itself is mostly completed; now I’m trying to draw in the terrain it’s on. It is located in the Willamette National Forest (Oregon) on a lot which slopes about 3 ft. from left to right as you look at the front of the cabin, and about a foot or so from back to front. I’m sharing a photo of the cabin and a screenshot of my Sketchup work so far.