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                                                                   EXHIBIT 10.9a


                             STERLING CHEMICALS ESOP
                                (FIRST AMENDMENT)

         WHEREAS, there is reserved to the Chief Executive Officer of the
Company in Section 9.1 of the Sterling Chemicals ESOP (the "Plan") the right to
amend the Plan, subject to certain restrictions set forth therein; and

         WHEREAS, the Company deems it advisable to amend the Plan;

         NOW, THEREFORE, Section 7.6(a) of the Plan is hereby amended to read as
follows:

                  "Distribution of a Participant's benefit from his Company
         Stock Account shall be made solely in whole shares of Company Stock,
         except that any fractional share shall be paid in cash."

                  All terms used herein that are defined in the Plan shall have
the same meanings given to such terms in the Plan, except as otherwise expressly
provided herein. Except as amended and modified hereby, the Plan shall continue
in full force and effect and the Plan and this amendment shall be read, taken
and construed as one and the same instrument.

                  This amendment may be executed in several counterparts, each
of which shall be deemed an original, but all of which shall constitute but one
and the same instrument which may be evidenced by any one counterpart.

         IN WITNESS WHEREOF, this Amendment has been executed on this December
___, 1996, effective for all purposes as of such date.


                                         STERLING CHEMICALS, INC.



                                         BY:
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                                         NAME:
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                                         TITLE:
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