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 § 150.325 ;
(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 port security plan.