my place is on pahoehoe lava that's 300-500 years old. there's a whole forest on it, but the excavator was pulling trees off the top of the rock, and they were coming up with a carpet of 3-4" of tangled roots and organic matter. you can literally roll up the organic layer like a carpet in a lot of places.
pahoehoe lava is mostly solid rock (it's not cinder), so to get it flat requires intense hammering. this area is flatt-ish, but it's kind of wavelike and there are higher and lower points that need to be flattened out. at the end of the first day, the excavator person had scraped the entirety of the forest off the top of the rock, and the whole second day he was hammering with the excavator to break up the rock in some of the higher areas to make it more flat. tomorrow i'm getting 30 tons of 2.5" base course rock delivered. then this coming weekend (weather permitting), the excavator will come back and create a driveway and house pad with that rock.
