Partially Underground: stemwall considerations

Been going back and forth on doing cob or earthbag or both for my solar gain, earthship inspired house.

I'm located across from the earthship community near Taos, NM. The weather is high desert, lots of sunlight, dry, relatively cold at night to warm days. We get some sub zero temps in winter. 80s to 90s summer. The soul is clay. My location is mostly subsoil with high calcium. We get winds into +20 mph daily with gusts to 60 mph and freak gusts even stronger than that.

My goal is to begin to build a house using what I have, which is time and clay. Purchasing this land means having nothing leftover  til its paid off, 1 year and 10 months from now. I have a shovel and giant pry bar and a 4 wheel barrel., which is amazing for its strength. I'm living in a bus next to the house site I have planned.

The foundation is roughly 30' x 40'. Actually the living portion of house foundation is more like 30' x 20' with remaining gates as storage. I already started digging because I get tired of thinking and want to do.
It's rocky. After digging over 2' I have enough rocks to build an entire stem wall. I'll go get pics of rocks after I write this. The more I dig the more I feel hidden from the wind. I want to keep digging but have come to this problem:

I need a sub grade footer and earth beamed wall til it reaches grade. If I could build a rubble earthbag footer and stemwall which sits beside a rubble trench, could I build cob wall off stem wall. I don't even have the money for earthbag or it wod be easy just to go with that.

Basically I want to build low to wind and for privacy and sound. I can do labor intensive but have no money for now.

Have you spoken with the earthship
community, they will have lots of experience to share

What are the alternatives anyway?
Rubble works best in a trench, not as a retaining wall which your stem wall will be.
If you use tyres you can build straight on the soil and build up from there.
If you land is full of rocks, what will you use as the earthen berms?
Can you use extra walls for privacy since going below ground level may cause drainage issues.
Does it ever rain there enough to flood the depression you have dug?

I have plenty of clay and rocks. Tires require getting right size and cost to bring them. I'm working alone. Maybe I need to do tires but I avoided them at first due to back pain but I'm already digging out boulders by hand tool.

You are doing well if that has been dug by hand, well done.

I hope you are not lifting those large rocks, thats a potential back problem.
You could break them witha feather anf wedge if you drilled a hole to start the process.
Otherwise use a system of either levers and pulleys to shift them.
If you are going to create a berm, you may find yourself double handling the dirt.
As for getting tyres delivered, I use a normal supplies run as am opportunity to get stuff.
Even if its only 4 tyres each trip, it builds up.

It looks like you are using a square mouth shovel to dig the soil, consider using a post hole shovel, they hold less, but are much easier to move.
And if you use a conventional single wheel barrow it may move across that rough surface a lot more easily.
I try and work to save any energy wasted, and that allows me to work for a much longer period
If I am walking across the building site I always carry something so it saves trips in the future

Nice pile of rocks, dude!
...and a wicked hole...makes me want to bring you 500 sacks and help out.

I know i have to pay a disposal fee when i buy tires. If i am correct, tires have to be quartered before going to the landfill because they "float back up" if left whole.

This leads me to think there is an industry around collecting and quartering used tires for a fee. I wonder if they would deliver truckloads to you at no charge. They still get their fee but dont have to quarter them and pay disposal.

Assuming i am correct, its worth asking a local tire company about the process.

If I'm going to do tires I'm going to start by using my regular bed f150 to haul them. Anytime I'm in town (20 miles). But that could keep me busy til I find a deal on delivery. From living across Earthship community I have noticed a few abandoned earthships that were in early stages and that made me doubt my ability more and consider earthbag. The abandon foundations are not related to Earthship Biotecture,  just us fools on the other side of the road who have less money. With earthbags if I failed, my yard wouldn't  be filled with tires.

I dug myself in, which feels great. I don't want to attract attention from road.. if the county ever decided to clamp down on building code. The main road is maybe 40 meters away and I wanted the view from road to be berms OR a low profile steel roof. Being low also allows me to gravity feed my water. I back the truck up on a berm and fill my tank which I have near the north end of the future building.

What I like about earthbags is not needing a concrete bond beam. Now being dug down in a rectangular shaped in foundation, tire walls seem to have good shear strength and less likely to shift if water got in? I can get over my aversion to concrete to make one bond beam I guess.

I think its important to note, I am doing this alone but can get help for a thing or two from my neighbors. My back feels like its hating me but Iike the labor. After years of babying my bad back i just said, 'screw it' I'm going to do this if possible. Some types of arthritis I think you have to labor so it doesn't hurt. Lucky for me I see much labor involved here. Unfortunately I have stopped digging because my plan is up in the air.

I think its a good idea to stop digging until you get a plan.
It may save alot of work.
Building a home does take a lot of work, and some do get sick of it.
By starting small, completing that  and then start adding as needed the tasks often seems a lot easier

Spend time planning now. look at systems, it will come to you soon.

I'm looking for plans that I can adjust to my site. Earthship Biotecture sells plans for thousands of dollars. This started as a earthbag thread but I think packing tires will suit my site best and its proven in this climate. I might not need a premade floor plan anyway. I'll go scour the earthship forum. Thanks for the guidance.