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                                    FIRST AMENDMENT
                                           TO
              SECOND AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP
                                           OF
                                  SHAMROCK LOGISTICS, L.P.



         This First Amendment to the Second Amended and Restated Agreement of
Limited Partnership of Shamrock Logistics, L.P. (the "PARTNERSHIP") is entered
into by and among Riverwalk Logistics, L.P., a Delaware limited partnership
(the "GENERAL PARTNER"), as General Partner of the Partnership, and the
Limited Partners of the Partnership, as hereinafter provided.

         WHEREAS, the General Partner and the other parties thereto entered
into that certain Second Amended and Restated Agreement of Limited Partnership
of the Partnership dated as of April 16, 2001 (the "AGREEMENT");

         WHEREAS, Article XIII of the Agreement permits the General Partner to
amend the Agreement to change the name of the Partnership and to take certain
other actions which, in the sole discretion of the General Partner, do not
adversely affect the Limited Partners in any material respect, without the
consent of Limited Partners.

         NOW THEREFORE, in order to change the name of the Partnership and to
reflect the change in name of the general partner of the General Partner, the
General Partner does hereby amend the Second Amended and Restated Agreement of
Limited Partnership of the Partnership as follows:

         1.     The definition of  "Partnership" in Article I is hereby
         amended in its entirety to read as follows:

                " 'PARTNERSHIP' means Valero L.P., a Delaware limited
         partnership, and any successors thereto."

         2.     The definition of "Shamrock GP" in Article I is hereby amended
         in its entirety to read as follows:

                " 'SHAMROCK GP' means Valero GP, LLC, a Delaware limited
         liability company and the general partner of the General Partner."

         3.     The first sentence of Section 2.2 is hereby amended to read as
         follows:

                "The name of the Partnership shall be Valero L.P."

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         IN WITNESS WHEREOF, the parties hereto have hereunto set their hands
as of the 31st day of December, 2001.


                              GENERAL PARTNER:

                              RIVERWALK LOGISTICS, L.P.

                              By:   Valero GP, LLC (formerly Shamrock
                                    Logistics GP, LLC), its General Partner



                              By: /s/ Curtis V. Anastasio
                              Name:       Curtis V. Anastsio
                              Title:      President and Chief Executive Officer

                              LIMITED PARTNERS:

                              All Limited Partners now and hereafter admitted as
                              limited partners of the Partnership, pursuant to
                              Powers of Attorney now and hereafter executed in
                              favor of, and granted and delivered to, the
                              General Partner



                              By: RIVERWALK LOGISTICS, L.P., General Partner, as
                              attorney-in-fact for all Limited Partners pursuant
                              to the Powers of Attorney granted pursuant to
                              Section 2.6 of the Agreement.

                              By:   Valero GP, LLC (formerly
                                    Shamrock Logistics GP, LLC), its
                                    General Partner



                              By: /s/ Todd Walker
                              Name:       Todd Walker
                              Title:      Corporate Secretary