Each Coast Guard official designated as a Captain of the Port (COTP) or Officer in Charge, Marine Inspection (OCMI) or Commanding Officer, Sector Office, is delegated the authority to—

(a) Issue International Oil Pollution Prevention (IOPP) Certificates;

(b) Detain or deny entry to ships not in substantial compliance with MARPOL 73/78 or not having an IOPP Certificate or evidence of compliance with MARPOL 73/78 on board;

(c) Receive and investigate reports under § 151.15; and

(d) Issue subpoenas to require the attendance of any witness and the production of documents and other evidence, in the course of investigations of potential violations of the Act to Prevent Pollution from Ships, as amended (33 U.S.C. 1901-1911), this subpart, or MARPOL 73/78.