worst case:
they may dig to expose the pipe if required
my backhoe has no problem digging through 12inches of reinforced concrete and Territory dirt compacted by 40 years of road trains
a garage, easy
ditto the above\
have had a repair done, on our easement on a neighbours property, the sewer pipe was sleeved from out in the street
After we asked the neighbour for access, just to be polite, it was not needed,
(really cool machinery)