They did two tests in Hattiesburg, Mississippi per the article below. http://www.atomicarchive.com/Almanac/Testing.shtml Two nuclear detonations performed in a subterranean salt dome formation, as part of a 1960's Atomic Energy Commission Test. The first detonation, to form the cavity, code-named Salmon, took place in 1964 using a 5.3 kiloton bomb, placed at the bottom of a sealed 2,710-foot shaft. The second nuclear blast, a relatively small 0.38 kilotons yield shot code-named Sterling, was exploded within Salmon's 110-foot diameter cavity more than two years later. Hmmmm, maybe this explains Favre's season last year. He must have stumbled into the test site and found some body altering residue.