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     engage, a list of all other known participants in the Holts' proposed
     activity or business, a description of the role of the Holts and the
     geographical location where the contemplated business or activity will be
     operated or engaged in. Zapata shall be obligated to make a good faith
     determination with respect to such contemplated business or activity and to
     respond to the Holts affirmatively or negatively by written letter within
     thirty (30) days of the receipt of such written notice, as hereinafter
     defined. In such response letter Zapata shall advise the Holts of whether
     it considers that such described activity would or would not be in
     violation of the covenant not to compete hereinabove set forth. Upon the
     failure by Zapata to respond to the Holts within thirty (30) days of
     receipt of written notice from the Holts, the proposed activity or business
     as set forth in the Holts' letter shall be deemed to be approved by Zapata
     and not in violation of this Agreement.

           6. This Agreement shall be governed by, and interpreted and enforced
     in accordance with, the laws of the State of Texas, without regard to
     principles of conflicts of law.

           7. In the event that any provision contained in this Agreement shall,
     for any reason, be judicially declared to be invalid, illegal,
     unenforceable or void in any respect, such declaration shall not have the
     effect of invalidating or voiding the remainder of this Agreement and the
     parties hereto agree that the part or parts of this Agreement so declared
     to be invalid, illegal, unenforceable or void in any respect will be deemed
     to have been stricken herefrom and the remainder will have the same force
     and effectiveness as if such part had never been included herein. In the
     event that the length of time or the scope of the covenants set forth in
     Section 1 hereof is deemed too restrictive in any court proceedings, the
     court may reduce such restrictions to those it deems reasonable under the
     circumstances.

           8. This Agreement shall not be assigned by a party without the
     consent of the other parties hereto.

           9. Any notice, request, demand, waiver, consent, approval or other
     communication which is required or permitted hereunder shall be in writing
     and shall be deemed given only if delivered personally or sent by facsimile
     transmission or by registered or certified mail, postage prepaid, return
     receipt requested, as follows:

               If to the Holts, then to:

                   Holt Companies
                   c/o B. D. Holt Co., d/b/a
                   Holt Company of Texas
                   S.W.W. White at Holt Avenue
                   San Antonio, Texas 78220
                   Facsimile Number: 210/648-0079

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