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                                                                    EXHIBIT 99.7

                 [LETTERHEAD OF BANC OF AMERICA SECURITIES LLC]



Board of Directors
Ultramar Diamond Shamrock Corporation
6000 North Loop 1604 West
San Antonio, Texas 78249

Ladies and Gentlemen:

We hereby consent to the inclusion of our opinion letter, dated May 5, 2001, to
the Board of Directors of Ultramar Diamond Shamrock Corporation (the "Company")
as Appendix D to the Registration Statement on Form S-4 to which this consent
is filed as an exhibit (the "Registration Statement") relating to the proposed
merger transaction involving the Company and Valero Energy Corporation and to
the reference in the Registration Statement to our firm and to our opinion
under the headings "SUMMARY - Opinions of Financial Advisors - UDS" and "THE
MERGER - Opinion of UDS's Financial Advisor." In giving the foregoing consent,
we do not admit (1) that we come within the category of persons whose consent
is required under Section 7 of the Securities Act of 1933, as amended (the
"Securities Act"), or the rules and regulations of the Securities and Exchange
Commission (the "Commission") promulgated thereunder and (2) that we are
experts with respect to any part of the Registration Statement within the
meaning of the term "experts" as used in the Securities Act and the rules and
regulations of the Commission promulgated thereunder.

Very truly yours,


/s/ BANC OF AMERICA SECURITIES LLC
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BANC OF AMERICA SECURITIES LLC

New York, New York
May 25, 2001