James Bradley Jr, 60, was arrested on Sunday after the discovery of the truck and has been accused of smuggling at least 100 illegal immigrants.
When truck was found, there were eight bodies and 30 to 40 undocumented Mexican and Guatemalan nationals.
One of the survivors later told investigators some immigrants managed to flee the scene before police arrived, swarming out of the truck when the rear doors opened to be whisked away by six black sport utility vehicles waiting for them nearby.
