just need to be careful because gas lines, water lines and sewer lines are below..but should be buried deep enough to not worry about damaging them while demoing the concrete. problem the concrete is nother thicker than 4 inches but you can dig around one of the edges and see how deep it is poured. you should hire this out....to someone that can just use a big sledge hammer. of course a powered jack hammer can be rented to make the job go faster too. good luck LJ