The landscape plan shows a walkway from the gate past the North Pit, joining a walkway around the raised garden and then extending back to the walkway around the deck in the back. One side of the walkway is, effectively, the North Pit, so we are going to start excavating it, using the North Pit as a working area.
We've "outlined" the walkway using the grubbing hoe on the one side and have expanded the North Pit over to the curving edge of where the walkway will be. The next step will be to dig all the dirt out, put in the two "walls" below ground level that will define the two sides of the walkway, then fill the space between the walls with rock and put down decomposed granite, as a base, and the "Oklahoma Thin" flagstones that we used for the walkway around the deck.
First step is to dig. I'm starting the excavation near the raised garden, working towards the gate. That way the gate can continue to be used until I dig out the part just in front of it. If I then back fill at that end first, the gate will be unusable for the shortest period of time.
The excavation goes thru the traditional (a) dirt under the grass, (b) construction left-overs, and (c) native clay. All of these layers, especially (b) and (c) have random rock in them, which we pull out. Then we hit the first layer of rock. We could use this as the base of our walkway, or we could take it out and go down another 6 to 8 inches to bedrock.
Part of the last 6 to 8 inches of rock comes out easily, so we removed it. But we are planning on leaving most of this layer in place and putting the walkway on top of it.
Once we have this much excavated, we can start putting the walls in that will separate the dirt beds from the walkway. We start with the outer wall, next to the un-excavated area. We use a piece of black plastic on that side to separate the concrete wall from the dirt. When (if) we eventually get to digging up that side, the plastic should allow a clean separation between the wall and the dirt.
Putting the wall between the North Pit and the walkway is more difficult because it has to be supported on both sides. It's hard to get either wall up high enough because our forms are only 16 inches tall. I'm doing it in layers, so I can pour concrete, wait for it to firm up, then remove the forms and raise them up to pour the next layer.
I added a piece of 4 inch PVC irrigation pipe stretching from one side of the walkway into the North Pit. This is to allow wiring or pipe to be run from one side to the other in the future. It is expected, for example, that we will want to run 3/4 inch or 1/2 inch irrigation for Zone 3 from the valve controller on the once side into both the North and South Pits, to provide a water supply.
Once the concrete was built up enough, I can then mortar on the limestone blocks on the top, to finish the wall off next to the North Pit. Now I could put the dirt back in, and let it settle before planting.
This should finish the North Pit, with the exception of putting in irrigation and planting. Both the North Pit and the South Pit should be Zone 2 of the sprinkler system.