<PAGE>
 
  b. Waiver, Severability and Amendment. This Agreement may not be modified or
     amended except by an instrument in writing signed by the parties hereto. No
     term or condition of this Agreement shall be deemed to have been waived,
     nor shall there be an estoppel against the enforcement of any provision of
     this Agreement, except by written instrument of the party charged with such
     waiver or estoppel. No such written waiver shall be deemed a continuing
     waiver unless specifically stated therein, and each such waiver shall
     operate only as to the specific term or condition waived and shall not
     constitute a waiver of such term or condition for the future or as to any
     act other than that specifically waived. If, for any reason, any provision
     of this Agreement is held invalid, such invalidity shall not affect any
     other provision of this Agreement not so held invalid, and each such other
     provision shall to the full extent consistent with law continue in full
     force and effect. If any provision of this Agreement shall be held invalid
     in part, such invalidity shall in no way affect the rest of such provision,
     together with all provisions of this Agreement, shall to the full extent
     consistent with law continue in full force and effect. If this Agreement or
     any portion thereof conflicts with any law or regulation governing the
     activities of the Company, the Agreement or appropriate portion thereof, as
     the case may be, shall be deemed invalid and of no force or effect.

  c. Headings; Governing Law. The headings of paragraphs herein are included
     solely for convenience and reference and shall not control the meaning or
     interpretation of any of the provisions hereof. This Agreement has been
     executed and delivered in the State of Texas; its validity, interpretation,
     performance and enforcement shall be governed by the laws of such State.

IN WITNESS WHEREOF, the Company has caused this Agreement to be executed and the
Executive has signed this Agreement, all effective October 1, 1994.

                                    ZAPATA CORPORATION


  
                                    By: /s/ Joseph L. von Rosenberg III
                                        ---------------------------------
                                        Joseph L. von Rosenberg III
                                        Vice President, General Counsel
                                        and Secretary



                                    /s/ Lamar C. McIntyre
                                    --------------------------------------
                                    Lamar C. McIntyre

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