Walter Miller's "Crucifixus Etiam" is a rather good story about this; essentially terraforming Mars as the new frontier for migrant labor, with all the harshnes

Walter Miller's "Crucifixus Etiam" is a rather good story about this; essentially terraforming Mars as the new frontier for migrant labor, with all the harshness that comes from those types of frontiers (including the fact that it is, largely, a one-way trip for the laborers, since their lungs atrophy due to the special breathing equipment they're attached to).