Doug, you need to prove you were on or near the perimeter while at Takhli. The CHECO report states herbicides were used around the perimeter of Thailand bases. larry Fisger (5/7/2018 post) correctly states the US Army Field Manual 3-3 and the drift zone of 500 meters. The key is proving via buddy letters, maps, your statements that you were withing those zone more days than not. If you had medical issues a letter from you physician (NEXUS letter) worded properly goes a long way toward proof. Most of this is in fact on line but you have to dig and look it up. I asked multiple times for and never received my complete/ or any helpful military records from St. Louis. It can and has been done contact me or Larry Fisher if we can help. I was there in 1966. LouB.