How to Find a Nuclear Test?

How do you search a 1000 km2 area to pinpoint places to look for evidence of nuclear testing?  CTBTO surrogate on-site inspectors learn to do exactly that. Over a three-year training cycle, 70 scientists from 44 countries are taught how to find evidence of a nuclear test.  Watch as the trainees take flight to scan a search area, use ground-penetrating radar, take environmental samples and more, as part of a two-week ‘Ground and Airborne Based Visual Observation Course” held at the Denel Overberg Test Range in South Africa.