There is no wellhead here as in normal "oil-wells", this is a salt dome storage facility.
The way these domes are set-up have those around here speculating that there will be very little B&C can do as the lack of normal wellhead configuration preclude the use of dynamite to shut it down. Then there is danger of actually fracturing the dome with a blast, causing the gas to vent all over, NOT a good thing to have happen, (this is dependent of course on how deep the top of that particular dome sets from ground level).
Wish I could be more specific but as I work for Duke on occassion I'm bound by confidentiality issues. It has yet to be determined but the company I work for does do "accident investigative surveys", whether we'll have guys out there, who knows, but we have done plenty that made the news in the past, ie.. the NJ explosion that burned down all those apartment buildings years ago. (Cause by some mob connected yahoos buring, via back-hoe, items they were intending to report as stolen. Seems the back-hoe operator knew he damaged the pipeline, but covered it up, causing the later expolsion. They haul'd 3-40' tractor trailer loads of office equipment, cars, trucks and junk off that property which they had buried in that immediate area and reported stolen for insurance purposes....)
As to the 16 Billion, that is total of capacity of the 3 domes/caverns total, the one burning does not affect the other two (hopefully).
Mike