You can cut the concrete, too, for that matter, with oxyacetylene, as long as
you wear certain protective gear. We have a few vault covers here that are
concrete covering the largest vaults we have. You need more than a manhole
hook to get one of those covers up.
And when you think you have it safely burried someone
drives a tunnel boring machine through it -
http://www.flickr.com/photos/23919135@N00/3426407496/
brandon