Don't know what the law is in Utah, but in NJ even illegals are covered by workers' compensation insurance. In NJ this benefit includes temporary disability payments, a lump sum permanent injury payment and 100% of medical costs incurred due to most workplace injuries - regardless of fault.
Good one! They are, indeed, entitle to Workers Comp here as well. I would be willing to bed they get a fair amount due to their increased concentration in the construction etc fields.