bling, that looks like explosives to me. Those boxes in this photo:
weigh 100 pounds each, so there would have to be 8000 of them, or something like them, to add up to 400 tons. The government's checking on it now, they'll surely let us know on Wednesday. Interestingly, the facility didn't seem fenced. I still favor the idea that the explosives were removed prior to our arrival, but this is some strong evidence to the contrary.