That is straight out of the well. I was shocked at the Sodium content as well. It is almost like a natural water softner. The formation is the Fox Hills formation, and is at 950' in this area.
The only issue I have with RO is that I am on septic here. If I RO I will have a highly concentrated waste stream and that will go down my septic and leach into my soil.
Also, in order to supply my house with water I would be looking at a system that would cost thousands. Has anybody build an economical whole house filter system on here yet?