EXHIBIT 15.1 INDEPENDENT ACCOUNTANTS' AWARENESS LETTER Securities and Exchange Commission 450 Fifth Street, N.W. Washington, D.C. 20549 Dear Sirs: We are aware that Diamond Shamrock, Inc. has included our report dated November 14, 1995 (issued pursuant to the provisions of Statement on Auditing Standards No. 71) in the Prospectuses constituting part of its Registration Statements on Form S-3 (Nos. 33-67166 and 33-59451) filed on August 9, 1993, and May 19, 1995, respectively, and on Form S-8 (Nos. 33-15268, 33-34306, 33-47761, 33-50573 and 33-59025) filed on June 22, 1987, April 13, 1990, May 6, 1992, October 6, 1993 and May 2, 1995, respectively. We are also aware of our responsibilities under the Securities Act of 1933. Yours very truly, /S/ PRICE WATERHOUSE LLP Price Waterhouse LLP San Antonio, Texas November 14, 1995