EXHIBIT 10.2.3


                          SECOND AMENDMENT TO THE 1988
                     UNION CARBIDE LONG-TERM INCENTIVE PLAN


          The 1988 Union Carbide Long-Term Incentive Plan (the "Plan") is hereby
amended as follows:

          1. The first paragraph of Section 5.3 of the Plan is hereby amended by
deleting the phrase ", but only to the extent  permitted  under  Section 5.5" at
the end thereof.

          2. The second  paragraph of Section 5.3 of the Plan is hereby  amended
to read as follows:

               "An option is only  exercisable by a participant  while
          the participant is in active employment with the Corporation
          except  (i)  in  the  case  of  a  participant's   death  or
          Retirement,  (ii) during a three-year  period  commencing on
          the date of a participant's termination of employment by the
          Corporation other than for cause,  (iii) during a three-year
          period  commencing  on  the  date  of  termination,  by  the
          participant or the Corporation, of employment after a Change
          in Control of the  Corporation , unless such  termination of
          employment is for cause,  or (iv) if the  Committee  decides
          that it is in the best interest of the Corporation to permit
          individual  exceptions.  An  option  may  not  be  exercised
          pursuant to this paragraph  after the expiration date of the
          option."

          3. Section 5.5 of the Plan is hereby deleted, and Sections 5.6 through
5.8 are hereby redesignated as Sections 5.5 through 5.7, respectively.

          4.  Section  6.4 of the Plan is hereby  amended by  deleting  the last
sentence thereof.

          5.  Section  11.1(ii)  of the Plan is hereby  amended by  substituting
"20%" for "35%" whenever "35%" appears therein.

          6.  Section  11.7 of the Plan is hereby  amended by deleting  the last
sentence  thereof,  and by  substituting  "20%" for "35%" whenever "35%" appears
therein.


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          7. The  amendments set forth herein shall be effective as of August 1,
1989.


Signed this 8 day of August, 1989.


                                              UNION CARBIDE CORPORATION


                                              By: /s/M. A. Kessinger




Attest:



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