I'm sure the fabricating, curing and shipping of it would take weeks...but I'm sure there are freepers out there who would have better technical information about this subject than I.
There was a case in the early days of on land production that a oil strike was so great in pressure it blew the pipe out into the sky...about half a mile of pipe..!
Curing concrete takes too long. You could pour a huge steel or iron block or cap and use it within days.
Say a 30ft x 30ft x 8ft thick. Drop it on the mutha.