You cant get trapped in an infested mine, but I believe it IS possible to get trapped in the basement of the occupied dverger towers (not the unoccupied ones with mines in the basement) if the stairs get destroyed and you dont have a portal kit with you or enough wood for a workbench and a ladder on you. You can get some wood from the support beams in the walls down there but I'm not sure if its enough for a workbench and ladder.