We have known for some time that radiation would be an issue when we build Mars colonies. The typical solution is to cover the habitats wil regolith. My response was the Canyon Colonies. With a canyon colony, radiation shielding is provided by the glass/water sandwich barrier enclosing the canyon along with the canyon's walls.

I'm a little bit puzzled why the radiation level was 2.5 times greater than the levels experienced at ISS. I think(?) this greater value maybe due to back scatter of secondary cosmic rays (GCRs) from the Martian regolith. The Moon should have a similar radiation level if this theory is correct.

Gary