2 This answer was slightly misleading in that the second passage would be easy to find.
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In Seneca Station, where the ghouls are,

there's a back room with radioactive barrels and such in it. There is also a manhole cover that leads to a passage that will take you to the train yard. There is aare multiple train carcars that you'll see when you exit the passage into the yard; on the other side of thatthose train carcars is another passage that will lead you to the station with The Family.

You'll want to be careful, though. They don't like unexpected visitors ...

In Seneca Station, where the ghouls are,

there's a back room with radioactive barrels and such in it. There is also a manhole cover that leads to a passage that will take you to the train yard. There is a train car that you'll see when you exit the passage into the yard; on the other side of that train car is another passage that will lead you to the station with The Family.

You'll want to be careful, though. They don't like unexpected visitors ...

In Seneca Station, where the ghouls are,

there's a back room with radioactive barrels and such in it. There is also a manhole cover that leads to a passage that will take you to the train yard. There are multiple train cars that you'll see when you exit the passage into the yard; on the other side of those train cars is another passage that will lead you to the station with The Family.

You'll want to be careful, though. They don't like unexpected visitors ...

1
source | link

In Seneca Station, where the ghouls are,

there's a back room with radioactive barrels and such in it. There is also a manhole cover that leads to a passage that will take you to the train yard. There is a train car that you'll see when you exit the passage into the yard; on the other side of that train car is another passage that will lead you to the station with The Family.

You'll want to be careful, though. They don't like unexpected visitors ...