What kind of critter dwelling is this ??

I'm bettin it's a armadiller. We have them nasty bastids down here. If it is, don't forget they are carriers of leprosy. That's somethin you can certainly do without.

Born and raised on the Plains of Colorado...Never heard of an Armadillo siting in the State

I stand corrected....Google says they do. Never too old to learn.

RRR and lgjhn may have nailed it what does an armadillo burrow look like - Google Search