With the ever increasingly likely chance of being discovered, the Railroad needs a new safehouse to increase its ability to process escaped synths. PAM requires the Sole Survivor to secure a location for a new Distribution Center. Once the location is secured, the newly designated "Mercer" safehouse, would alleviate that outcome.
Walkthrough[]
The Sole Survivor will be directed establish a safehouse at a randomly selected settlement location that the player has not yet secured.
PAM's found a suitable location for a new safehouse. She wants me to secure the site and fortify it.
Build defenses (100%) at <Location>
It looks like PAM has found a decent site for a new safehouse. Now I just need to build some defenses so it's secure.
Report back to PAM
Mercer Safehouse is fortified and clear of hostiles. Time to let PAM know the good news.
Notes[]
The safehouse location is not determined until you speak to Doc Carrington at the conclusion of Boston After Dark. You can save before talking to him and reload if you prefer a different location (some are more difficult and farther away than others).
Since guard posts must be manned to provide defense, plan to build at least two light turrets. Bringing the materials with you might save you a trip back, especially for a small remote settlement location.