The excavated trench is for a hallway to a door on a ledge of the cliff. Drains will be laid in this prior to the floor pour.

The plan is to be 'somewhat off the grid'. The structure is designed and will be positioned to take advantage of passive heating and cooling.
Temp of the sub soil at the basemnt floor depth remains a constant 72f.
The open end of the tunnel that I trenched will take advantage of a cool breeze that comes from the valley below.
There will be a tremendous thermal mass within the living space to stabilize temp swings.

I could have pumped the hole dry. But, I didn't have a pump, did have a backhoe and, needed the trench there anyway.

This afternoon I dug and moved two more loads of rock. One huge boulder that must have been 4 feet around. Almost never got it loaded on the truck.