Bungies post pretty well covers it.
It is possible to pull the old galvanized piping out from beneath the foundation and house with the proper equipment (provided there are no offsets in the line). A new line is attatched to the old line before it is pulled, and is towed into place as the old line is pulled out.
There would still be the need to access the area where the connections are to be made. HDPE pipe is the preferred material for this type of replacement technique.