http://www.polygon.com/2015/6/7/8743107/someones-already-figured-out-where-vault-111-is-in-fallout-4

Worth a read. I love when people do things like this. Spoiler alert (I guess?)

Actually, that was some good work on their part, and good estimating as well. I was very impressed with their estimation of the yield of the detonation, as MT weapons do not seem canon imho.

possibly, but they could be wrong. if you overlay a scale map of the DC wasteland and an actual DC area map it doesn't necessarily remain consistent in scale or locations. I don't consider these maps people are making to be any better than speculation, some what educated speculation but still no proof all the same. I will wait and see. I hope they're right though since they seem to all agree that based on that info the map will be significantly larger.