When it originally went live, ISSI wasn't fully fleshed out so there was also a site at Motorola HQ in Chicago that monitored the system and was able to make changes quickly when problems arose. Louisiana also got permission from the FCC to set some of their mobile sites outside of their normally authorized coverage area to provide communications where none of the existing sites had coverage. I believe one went to Florida, one on an island off the coast in Alabama and another on a barge/ship south of the MS/AL boarder. Others were used near the mouth of the Mississippi River to help extend coverage there.
When the explosion happened, I had just arrived in New Orleans and had not yet programmed my scanner for the area, but using band scanning with wildcards for talkgroups I heard a transmission calling for "as many coast guard and firefighting ships you can get and at least two large helos". From that, I understood it was one of two things, a drill or something big had just happened. Nothing had made any of the news yet so it was hard to tell just what was going on. With just band scanning, it was also hard to keep on the in-use talkgroups, especially since they probably were not always affiliated to the local sites. With the morning news headlines, I understood the seriousness of what I had heard.
