#1. Once you’ve reached the dam, enter the first generator building/tower to the left. You'll find a datapad beside a rocket launcher.
Recording: Ceph Technology
#2-3. After reaching the main building, ride any of the two lifts down then open your nanovisor to tag two datapads in the lower facility. They're both located on top of the consoles.
Recording: Liberty Beam and Ceph Energy Collection Activities
#4. Head to the central elevator and ride it to the top of Nexus. As soon as the elevator stops, open your nanovisor and scan the area for the last datapad in the mission. It should be located on a terminal to the left of the elevator door.