Lou, please review this map. I took the Takhli Master Plan and matched it with the 2016 Google Map. The perimeter is almost the same as the 1966 or 1968 Master Plan.
The outside red line is the old base perimeter. My only concern is the runway. The old master plan shows the perimeter just beyond the far side of the runway. Can you look at that for me. If that is correct, then most of the aircraft parking ramp is in the drift zone. That would mean a lot more people were exposed.
The inside red line is the 500 meter drift area as described in Army FM3-3, page 5-5.