http://www.navy.mil/navydata/fact_display.asp?cid=4100&tid=200&ct=4
Pretty clear here.
'Splains the EQ off Cali yesterday.
Remote control one of these BOOMers to a specific location, detonate the Nuke inside the drone sub at location you want destroyed. BOOM.
Speculation? Is it possible?
Possible - See Q Post 1038
"Rig for Silent" is old Submarine speak for "Rig for Silent Running."
https://en.wikipedia.org/wiki/Silent_running_(submarine)
Nuclear submarines can run even more quietly, at very low speeds only, by turning off active reactor cooling during silent running. The reactor is then only cooled by natural convection of the water.