This subpart applies to you if you are a responsible party for a vessel as defined under Section 1001(37) of OPA 90 (33 U.S.C. 2701(37)) or a deepwater port as defined under Section 1001(6) of OPA 90 (33 U.S.C. 2701(6)), unless your OPA 90 liability is unlimited under Section 1004(c) of OPA 90 (33 U.S.C. 2704(c)).