Actually did this just this fall.
Pipe needed was 1/2 rigid. Ran 3/4 to cover future.
Took 1st piece of 3/4, put coupling end with weather proof ko seal on it, wrapped in duct tape. Then proceeded to pound coupling end vertically under 4' walkway. The pounding started at 7" below grade, ended up 16 below grade. Cut off damaged end, threaded on new threads, and the rest is easy.
OK, had a laborer do the pounding, but still it was my idea...
