"CV" is believed to mean Cerberus Vent...the source of Smokey the Monster when it comes up out of the ground to scan, or kill, or whatever.

Note the large number of CV's in the vicinity of the Black Rock, and the note
"Here be Dragons"...even "Lift up your hearts to God"...and "site of increased Cerberus activity".

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“Because, in a land of predators, the lion never fears the Jackal.” – Dexter S3E03 “The Lion Sleeps Tonight”