In order to get into the locked bunker in the National Guard Depot, you need to complete an unmarked side quest called the Keller Family Refuge. The Keller family (all members but one) hid in this bunker when the war started. To make sure all family members would show up at the bunker, Mr. Keller gave each family member one number from the access code. You will need to collect the Keller Family Transcripts to get the complete code.
The transcripts can be found in the following locations:
- VAPL-58 Power Station: This tape is NOT needed because it doesn't have an access number on it. It just gives a history of the family.
- Hallowed Moors Cemetery north of Bigtown
- The Grisly Diner
- Rockbreaker's Last Gas
- Across the river from the Anchorage Memorial
Unfortunately, once you're inside, you will see that the Keller Family didn't make it. Mr. Keller turned into a feral 'glowing one' from his trips outside of the bunker and exposure to radiation and he is still alive in the bunker.
One item of notable loot is the experimental MIRV weapon. It is similar to the Fat Man weapon in appearance but it shoots multiple mini nukes at one time.