A manned deepwater port's person in charge of vessel operations must maintain radar surveillance of the safety zone or area to be avoided when:
(a) A tanker is proceeding to the safety zone after submitting the report required in Sec. 150.325 in this part;
(b) A tanker or support vessel is underway in the safety zone or area to be avoided;
(c) A vessel other than a tanker or support vessel is about to enter or is underway in the safety zone or area to be avoided; or
(d) As described in the deepwater port security plan. [USCG-1998-3884, 71 FR 57651, Sept. 29, 2006, as amended by USCG-2013-0397, 78 FR 39182, July 1, 2013]