Today was a long 4 hour drive from Pleasant Hill to Garberville, which I must admit I was unable to remain awake for. I apologized repeatedly to my coworker, but I kept falling asleep.
Once we were at the site, things went fine. We located the boring locations, recorded water depths in groundwater wells, and the drillers arrived to core to asphalt and concrete.
The concrete was the only problem. Most of the asphalt was between 2 and 3 inches thick. In contrast we had two locations in concrete. One ended up being only 9 inches thick. I say "only" because the hole prior was 14 inches of concrete including an encounter with index finger thick rebar. it took the drillers four attempts to get through it.
Tomorrow (in the predicted 90% chance of rain with over an inch expected), we will begin our drilling for soil samples.