Sorry. Aurora Mass Drivers can't move 'rock'. The trans-newtonian physics they operate on can only hurl TN elements. You'll have to bombard your enemy with expensive minerals, not free dirt.
And if you have a human meatbag encased in a single occupant sized TN element composed space coffin?
Given the number of tons of TNE in a mass driver packet, the human (or other species) meatbag is a rounding error.