Digging out instead of burying?

Hello! Long time lurker, first time poster...

So here's the deal, I refuse to borrow or go into any more debt, I am already struggling to pay back student loans for an education that didn't advance my job opportunities. I have been priced out of the housing market and almost out of the rental market as well. I am stuck in a position where I am lucky if I make it to the end of the month without dipping into my overdraft protection. - that's the short of my story.

Now let's get into the meat and potatoes. I live in a very small town that is surrounded by areas of crown land. I have plenty of places to fish and hunt, plus access to some amenities.. food and fuel.. beer (lol). Now It's not exactly illegal to camp on Crown land in Canada, as long as your structure isn't permanent and you move it every 21 days or so, but I plan to secretly squat on crown land. The way I would like to do this, is to literally dig into a hill side (or possibly under a sturdy low traffic bridge near by to avoid potential problems with the spring melt) and dig out a dome shaped space that I would line with a giant RV tarp I have, sandbags and barbed wire... essentially a earth bag, but working with an exoskeleton instead of an interior frame, like lining a dugout igloo.

I am trying to think of the safest way I can do this when it comes to wall and roof supports while I carve it out. It'll have a pretty heavy load to bear, since I intend to take advantage of the geothermal energy. In my location, that's about 4' down until you benefit from the stable 10-12 Celsius earth, and in a climate that can reach below -40 C in the winter, it's important that I utilize this heat source to supplement the boat/fishing shack wood stove that I have. The space doesn't have to be large, or even have any windows. Here's an example close to what I'd like to do, except more underground and disguised:



I realize that this isn't exactly legal, however it's not a criminal offense, it's just a fineable one, a fine I would be willing to pay should I get caught. I also realize that most people who go underground, first excavate, build, and then bury, but because I'm squatting this will have to be as inconspicuous as possible. I would love it if I could get any tips, hints, advice or alternatives from this community. I would be extremely grateful.

Cheers