Darla (Miller) Brown, the best map I have found is on the very first post on this site (Paul Seager). It is a copy of an official map of Takhli RTAFB. I used that map in my claim, I measure 500 meters from the left edge and bottom and drew a line and shaded the enclosed area. Per US Army Field Manual FM 3-3 that is the over spray area for herbicides (use herbicides not Agent Orange in any VA Claim). In that Field Manual Section 5, Page 5 the last paragraph talks about the "Drift" area of 500 Meters which equals 1640.42 feet. If I can help my email is firstname.lastname@example.org. LouB.