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                                 EXHIBIT 10.31
                           RESTRICTED STOCK AGREEMENT

         This Restricted Stock Agreement ("Agreement") is between VALERO ENERGY
CORPORATION, a Delaware corporation ("Valero"), and JERRY D. CHOATE, presently a
Non-Employee Director of the Board of Directors of Valero ("Outside Director");
who agree as follows:

         1. Introduction. Pursuant to the Valero Energy Corporation Restricted
Stock Plan for Non-Employee Directors (as may be amended, the "Director Plan"),
Valero granted 1,190 shares of its Common Stock, $.01 par value ("Restricted
Shares"), under the Director Plan to the Outside Director. As directed by the
Director Plan, the parties enter into this Agreement to evidence the terms,
conditions and restrictions applicable to the Restricted Shares.

         2. The Director Plan, Restrictions on Transfer. The Outside Director
has read and understands the Director Plan, which is incorporated herein by
reference for all purposes, and agrees to the terms and conditions applicable to
the Restricted Shares and the rights and powers of Valero as provided therein.
In addition, the Outside Director agrees as follows;

                  2.01 Except as provided in the Director Plan and this
          Agreement, Restricted Shares may not be sold, exchanged, pledged,
          hypothecated, transferred, garnished or otherwise disposed of or
          alienated prior to vesting. The Outside Director agrees that
          certificates representing the Restricted Shares may be imprinted with
          a legend to this effect.

                  2.02 Restricted Shares granted hereunder shall vest and accrue
          to Outside Director in the following increments: 397 shares on the
          date of the annual meeting of stockholders of Valero Energy
          Corporation for election of directors of Valero ("Annual Meeting")
          occurring in 2004; 397 shares on the date of the Annual Meeting
          occurring in 2005; and 396 shares on the date of the Annual Meeting
          occurring in 2006. The restrictions may terminate prior to the
          expiration of such period as set forth in the Director Plan.

                  2.03 Valero shall retain all certificates representing
          Restricted Shares, together with stock powers executed by the Outside
          Director pertaining to such Restricted Shares, until the restrictions
          on such Restricted Shares described in the Director Plan or contained
          in this Agreement lapse.

                  2.04 If Restricted Shares are forfeited, the Transfer Agent of
          Valero is instructed, upon confirmation by the Corporate Secretary of
          such forfeiture, to surrender the certificates representing such
          shares for cancellation.

         3. Limitation. The Outside Director shall have no rights with respect
to any Restricted Shares not expressly conferred by the Director Plan or this
Agreement.

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         4. Miscellaneous. All capitalized terms contained in this Agreement
shall have the definitions set forth in the Director Plan unless otherwise
defined herein. This Agreement shall be binding upon the parties hereto and
their respective heirs, legal representatives, successors and assigns.

         EFFECTUVE as of the 24TH day of APRIL, 2003.

                                       VALERO ENERGY CORPORATION


                                       ---------------------------------------
                                       Mike Crownover
                                       Vice President - Human Resources


                                       ---------------------------------------
                                       JERRY D. CHOATE
                                       Outside Director