The Vault - Fallout Wiki

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The Vault - Fallout Wiki
The Big Dig
The Big Dig.gif
Quest data
Bobbi's place
The Dig
NH&M freight depot
Given ByBobbi No-Nose
RewardBottlecaps x(200-400)
Ashmaker (if siding with Fahrenheit)
Editor IDMS16
Base ID00022a07

The Big Dig is a quest that can be obtained within the Commonwealth, in Fallout 4..


A mysterious ghoul calls out from behind a locked door, looking for a stranger to take on a detail deprived quest. Is this the opportunity of a life time, or just another easy way in which to get killed?


  1. As the Sole Survivor explores Goodneighbor, they will come across a locked door in an alleyway, in which a ghoul is peering out of from within. Speaking to this ghoul, by the name of Bobbi, it is discovered that she is looking for strangers at Goodneighbor, in order to complete a job. Only should the Sole Survivor accept, which will also mean accepting the job without knowing the full details, will Bobbi finally unlock the door, in which she will lead the Sole Survivor into the tunnels underneath her home. As they walk towards the tunnels, Bobbi will explain that the job is to help her gain access to the Diamond City strongroom, where she plans on robbing the mayor blind.
  2. Once inside of these tunnels, a couple of diggers will be found breaking their way through a crumbling wall, in which they will soon flee for their lives after breaking through and discovering a mirelurk nest within.
  3. After dealing with the mirelurks in this area, the Sole Survivor will need to report back to Bobbi, who will mention that the next step will be to acquire a specialist, in which the Sole Survivor will then need to meet with her secretly in Diamond City, at the noodle stand, in order to gain further details.
  4. After meeting Bobbi at Diamond City, she will reveal that the specialist's name is Mel, who is being held within the city's prison for an unknown reason. The Sole Survivor will need to break Mel out, through a myriad of options:
    1. Activate the protectron at the back of the station, which then goes haywire and begins attacking everything in sight, giving a good enough distraction to lockpick Mel out and escape unnoticed.
    2. Intimidate the guards in releasing Mel early, which reveals that he was only there for minor reasons, and was to be released soon anyways.
    3. Bribe the guards with 300 bottlecaps.
    4. Kill the guards and/or steal a key allowing the cell to be unlocked and Mel to escape.


  1. Once Mel has been freed, and the team heads back to the dig site, Mel will introduce his own personal creation, by the name of Sonya, who was specially designed to clear out areas of loose dirt, which will help them dig much faster than they could normally.
  2. The Sole Survivor will then need to escort the party through these tunnels, periodically instructing Sonia to open the way into a new area, which will lead the party through a subway station next, until finally reaching the support beams of the strong room.
  3. After properly preparing for breaching the strong room, Sonya will sacrifice herself to collapse the ceiling in, allowing access to the strong room. Traveling up and in, the Sole Survivor and party will travel into the strongroom, where the Sole Survivor and Mel immediately realize that they were tricked, and that Bobbi had brought them in to rob Hancock, not Mayor McDonough.
  4. Hancock's personal bodyguard and lover, Fahrenheit, will be awaiting the party along with a couple of Triggermen, having heard Sonia's exploits, and preparing for Bobbi.
  5. Should the Sole Survivor choose to remain loyal to Bobbi, even after her deceit, they will need to kill Fahrenheit and her guards, in which Bobbi will pay out a measly final pay of 200 caps.
  6. Should the Sole Survivor choose to side with Hancock and Fahrenheit, they will need to either kill Bobbi, or talk her down, in which she will simply head back home with her head down. Fahrenheit will reward the Sole Survivor with the Ashmaker, a unique minigun, and the Sole Survivor will remain in the good graces of Hancock, allowing for him to become a permanent companion.

Quest stages

Meet Bobbi inside
Join the dig
Exterminate the Mirelurks (3/3)
Talk to Bobbi
Meet Bobbi in Diamond City Bobbi promoted me after I exterminated a group of Mirelurks in her basement. She asked me to meet her in Diamond City to tell me more about the job.
Get Mel Out of Jail Bobbi revealed that we are digging to the Diamond City strongroom to steal what's inside. She asked me to recruit a man named Mel who is up in Diamond City Security.
Recruit Mel
Meet the gang in the Dig I broke a man named Mel out of Diamond City Security. Now I need to meet up with Bobbi in the tunnel and start digging to the Strongroom.
Dig to the Strongroom Mel brought a robot to help with the dig. Now all we have to do is use it to dig our way to the Diamond City strongroom.
Meet with the gang in the strongroom basement
Get out of the basement
Enter the Strongroom
Talk to Fahrenheit Fahrenheit thanked me for not letting Bobbi steal from Hancock's strongroom. She asked that I speak to Hancock in person.


While traveling through the tunnels and using Sonia to clear the way, there is a secret wall of dirt that must be sifted through, in which the Sole Survivor will discover a high tier creature, as well as parts of power armor, the X-01 model past level 28. Should Sonia be destroyed before finding this secret area, it will be impossible to enter.


  • On the PS4 the command to blow up fragile walls can disapear making it impossible to get through the quest.
  • It is easily possible for Sonia to become stuck during the party's travels, which will make it largely impossible to get through the quest.
    • This can be bypassed by saving and then reloading, which will frequently move the NPCs around, effectively getting Sonia back on track.
    • On PC you can also use the "moveto player" command to get Sonia unstuck.
Fallout 4 quests