Section 138.500 - Notification prior to audit(a) The owner or managing operator of a towing vessel must notify the local OCMI at least 72 hours prior to an external audit being conducted under this part.(b) The Coast Guard may require that a Coast Guard representative accompany the auditor during part, or all, of an external audit.(c) The Coast Guard may conduct a separate audit of the owner or managing operator or its towing vessels, at its discretion.