We tried to dig a trench last year to fill with drainage rock and gravel for a foundation, but hit the camp's main water line and, well, you know the rest. Water fifteen feet in the air. Zero water pressure for all of Camp Mitchell. Luckily our maintenance guy is a real pro. He was out and had it fixed in under an hour.
So we had to move our site and start digging all over. More carefully this time. So far so good. We dug the trench without hitting any lines and filled it with stones. Instead of buy proper gravel we collected sandstone rocks from the woods and busted them with a sledge hammer until they were the proper size. This improvisation may cost us, but it may work out just fine. I'm betting on the latter. Anyway we put topped it off with some SB2 gravel and cement to keep the run-off from flowing into our trench.
Cob is made of sand, clay, and straw. We are testing out the clay and straw we have been able to find so far to see if the materials are of proper quality.
If you know of anywhere we can find clay near Morrilton or Petit Jean let us know!