A sump pump sits in a pit and pushes water out through a discharge pipe, so it is wet, sometimes dirty, and wired to power. Cut the electricity first, then disconnect the discharge and lift the pump out, keeping in mind it holds water and debris.
Pro tip: A move is a good time to test the pump and replace an aging one, since a failed sump pump means a flooded basement.
Watch out: Never handle a sump pump or reach into the pit with the power connected. Unplug it first.