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                                                                    EXHIBIT 10.4

                             FOURTH AMENDMENT TO THE
                            STERLING CHEMICALS, INC.
            AMENDED AND RESTATED HOURLY PAID EMPLOYEES' PENSION PLAN

         WHEREAS, there is reserved to the Company the right to amend the
Sterling Chemicals, Inc. Amended and Restated Hourly Paid Employees' Pension
Plan (as amended, the "Existing Plan"); and

         WHEREAS, the Company deems it advisable to amend the Existing Plan in
the manner hereafter set forth;

         NOW, THEREFORE, the Existing Plan is hereby amended effective as of the
dates specified herein:

         Section 1.     Amendment of Section 2.1 of the Existing Plan. Effective
October 1, 1997, the last two paragraphs under Section 2.1 are amended to read
in their entirety as follows:

         Thereafter, each employee of the Employer who is represented by a
         collective bargaining unit that has negotiated a collective bargaining
         agreement with the Employer making the Plan available to such employee,
         shall become a participant in the Plan on the date he or she becomes a
         member of the collective bargaining unit.

         In no event shall leased employees (as defined in Code section
         414(n)(2)) be considered employees who are eligible to participate in
         the Plan.

         Section 2.     Amendment of Section 4.5 of the Existing Plan. Effective
October 1, 1997, Section 4.5 is amended by adding a paragraph to the end
thereof, to read in its entirety as follows:

         Notwithstanding any provision to the contrary, if benefits do not
         commence to be paid prior to April 1st following the year in which the
         Participant attains age 701/2 because the Participant is still
         employed, in no event shall the benefits be less than the actuarial
         equivalent of the benefits that would have been payable as of April 1
         following the calendar year in which the Participant attained age 70
         1/2 if benefits had commenced to be distributed on that date, plus the
         actuarial equivalent of any additional benefits accrued after that
         date, reduced by the actuarial equivalent of any distributions made
         after that date. Actuarial equivalence shall be determined using the
         Plan's assumptions for determining actuarial equivalence for purposes
         of satisfying Code section 411. This provision shall be applied in
         accordance with Notice 97-75 and any subsequent IRS guidance.

         Section 3.     Amendment of Section 6.3 of the Existing Plan. Effective
February 15, 2002, Section 6.3 is amended by adding the following sentences at
the end thereof:

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         Upon his or her termination, his or her nonvested accrued benefit shall
         be forfeited. Any amount forfeited under the preceding sentence shall
         be restored upon such Participant's subsequent reemployment, unless he
         or she incurs five consecutive one-year Breaks in Service prior to
         being reemployed."

         Section 4.     Amendment of Section 8.1(a) of the Existing Plan.
Effective October 1, 2000, Section 8.1(a) is amended to read in its entirety as
follows:

         (a)      Adjustment if Benefit Not Single Life Annuity. A benefit
         payable in a form other than a single life annuity must be adjusted to
         an actuarial equivalent single life annuity before applying the
         limitations of this Section. For this purpose, the actuarially
         equivalent single life annuity is equal to the greater of (i) the
         annuity benefit computed using the interest rate and mortality table
         (or other tabular factor) specified in the Plan for adjusting benefits
         in the same form, and (ii) the annuity benefit computed using a 5%
         interest rate assumption and the mortality table used to calculate lump
         sum payments and described in Section 17.12(b). In determining the
         actuarial equivalent single life annuity for a benefit form other than
         a non-decreasing annuity payable for a period of not less than the life
         of the Participant (or, in the case of a qualified pre-retirement
         survivor annuity, the life of the surviving spouse), or decreases
         during the life of the Participant merely because of (a) the death of
         the survivor annuitant (but only if the reduction is not below 50% of
         the annual benefit payable before the death of the survivor annuitant),
         or (b) the cessation or reduction of social security supplements or
         qualified disability payments (as defined in Code section 401(a)(11)),
         "the applicable interest rate", as described in Section 17.12(b), will
         be substituted for "a 5% interest rate assumption" in the preceding
         sentence. No actuarial adjustment to the benefit is required for (a)
         the value of a qualified joint and survivor annuity, (b) the value of
         benefits that are not directly related to retirement benefits (such as
         a qualified disability benefit, pre-retirement death benefits, and
         post-retirement medical benefits), and (c) the value of post-retirement
         cost-of-living increases made in accordance with Code section 415(d)
         and the related regulations. The annual benefit does not include any
         benefits attributable to employee contributions or rollover
         contributions, or the assets transferred from a qualified plan that was
         not maintained by the employer.

         Section 5.     Amendment of Section 8.1(b) of the Existing Plan.
Effective October 1, 2000, Section 8.1(b) is amended to read in its entirety as
follows:

         (b)      Adjustment if Benefit Commences Before Social Security
         Retirement Age: If the annual benefit of the Participant commences
         before the Participant's social security retirement age, but on or
         after age 62, the defined benefit dollar limitation shall be determined
         as follows:

                  (i)      If a Participant's social security retirement age is
                  65, the dollar limitation for benefits commencing on or after
                  age 62 is determined by

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                  reducing the defined benefit dollar limitation by 5/9 of one
                  percent for each month by which benefits commence before the
                  month in which the Participant attains age 65.

                  (ii)     If a Participant's social security retirement age is
                  greater than 65, the dollar limitations for benefits
                  commencing on or after age 62 is determined by reducing the
                  defined benefit dollar limitation by 5/9 of one percent for
                  each of the first 36 months, and 5/12 of one percent for each
                  of the additional months (up to 24 months) by which benefits
                  commence before the month of the Participant's social security
                  retirement age.

         If the annual benefit of a Participant commences prior to age 62, the
         defined benefit dollar limitation shall be an annual benefit that is
         the actuarial equivalent of the defined benefit dollar limitation for
         age 62, as determined above, reduced for each month by which benefits
         commence before the month in which the Participant attains age 62. The
         annual benefit beginning prior to age 62 shall be determined as the
         lesser of (i) the equivalent annual benefit computed using the interest
         rate and mortality table equivalence for early retirement benefits
         described in Section 4.4, and (ii) the equivalent annual benefit
         computed using a 5% interest rate and the applicable mortality table
         referenced in Section 17.12(b).

         Section 6.     Amendment of Section 8.1(c) of the Existing Plan.
Effective October 1, 2000, Section 8.1(c) is amended to read in its entirety as
follows:

         (c)      Adjustment if Benefit Commences After Social Security
         Retirement Age. If the annual benefit of a Participant commences after
         the Participant's social security retirement age, the defined benefit
         dollar limitation shall be adjusted so that it is the actuarial
         equivalent of an annual benefit of such dollar limitation beginning at
         the Participant's social security retirement age. The equivalent annual
         benefit beginning after social security retirement age shall be
         determined as the lesser of (i) the equivalent annual benefit computed
         using the interest rate and mortality table specified in the plan for
         purposes of determining actuarial equivalence for delayed retirement
         benefits, and (ii) the equivalent annual benefit computed using a 5%
         interest rate assumption and the applicable mortality table referenced
         in Section 17.12(b).

         Section 7.     Amendment of Section 8.1 of the Existing Plan. Effective
October 1, 2000, Section 8.1(e) is deleted, and the subsequent subsections
renumbered accordingly.

         Section 8.     Amendment of Section 8.3 of the Existing Plan. Effective
with respect to any Participant who performs an Hour of Service on or after
October 1, 2000, the limitation described in Section 8.3 shall not apply.

         Section 9.     Amendment of Section 8.4(e) to the Existing Plan.
Effective October 1, 1998, Section 8.4(e) is amended by deleting the last two
sentences of the third paragraph, and by amending the last sentence of the
second paragraph thereof to read in its entirety as follows:

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         Notwithstanding anything to the contrary in the definition as stated
         above, Compensation shall include any and all items which are
         includible in Compensation under Code section 415(c)(3)(D), including,
         effective for Limitation Years beginning on or after October 1, 2001,
         qualified transportation fringe benefits excluded from income pursuant
         to Code section 132(f)(4).

         Section 10.    Amendment of Section 8.5 of the Existing Plan. Effective
October 1, 2000, Section 8.5(d) is deleted and the subsequent subsections are
renumbered accordingly.

         Section 11.    Amendment of Section 8 of the Existing Plan. Effective
December 12, 1994, Section 8 is amended by adding a new Section 8.6 thereto to
read in its entirety as follows:

         8.6      Special Provisions for Employees Who Enter the Armed Forces.
         Notwithstanding any provision of the Plan to the contrary,
         contributions, benefits, and service crediting with respect to
         qualified military service shall be determined in accordance with Code
         section 414(u).

         Section 12.    Amendment of Section 9.3(d) of the Existing Plan.
Effective October 1, 2001, Section 9.3(d) is amended to add a paragraph at the
end thereof to read in its entirety as follows:

         Notwithstanding anything in this Section to the contrary, a Participant
         may waive (with applicable spousal consent) any requirement that the
         written explanation of the joint and survivor annuity be given at least
         30 days before the annuity starting date if the Participant is given a
         notice clearly informing him or her of his or her right to a period of
         at least 30 days to consider his or her election, and the distribution
         commences more than seven days after the notice is given. In addition,
         to the extent provided for in regulations, the explanation of the joint
         and survivor annuity may be given, and the Participant may waive the
         normal form of benefit payment, after the annuity starting date,
         provided the distribution commences at least 30 days after such
         explanation is given, unless the 30-day period is waived in accordance
         with the previous sentence.

         Section 13.    Amendment of Section 9.6 of the Existing Plan. Effective
December 31, 1998, Section 9.6(b) is deleted and the subsequent subsections are
renumbered accordingly.

         Section 14.    Amendment of Section 9.6(b) of the Existing Plan.
Effective December 31, 1998, Section 9.6(b) (as renumbered pursuant to Section
13 above) is amended to read in its entirety as follows:

         (b)      Notwithstanding anything in the Plan to the contrary, a
         Participant's benefits shall commence to be distributed to him or her,
         or be distributed to him or her, not later than April 1st of the
         calendar year following the later of (i) the calendar year in which the
         Participant attains age 70 1/2 or (ii) the calendar year in which the
         Participant retires, provided, however, that clause (ii) shall not
         apply in the case of a Participant who is a "five percent owner," as
         defined in Code section 416(i).

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         Distributions shall be made in accordance with the regulations under
         Code section 401(a)(9).

         If a Participant dies before his or her entire interest under the Plan
         has been distributed to him or her, the remaining portion of such
         interest will be distributed at least as rapidly as under the method of
         distribution being used as of the date of his or her death.

         Section 15.    Amendment of Section 9.6(c) of the Existing Plan.
Effective October 1, 2001, Section 9.6(c) (as renumbered pursuant to Section 13
above ) is amended by replacing the word "Payment" appearing at the beginning
thereof with the words "Where payment".

         Section 16.    Deletion of Section 9.6(d) of the Existing Plan.
Effective October 1, 2002, Section 9.6(d) (as renumbered pursuant to Section 13
above) is deleted.

         Section 17.    Amendment of Section 9.7 of the Existing Plan. Effective
October 1, 2000, Section 9.7 is amended to read in its entirety as follows:

         9.7      Payment of Small Amounts. If at any time following his or her
         retirement or other termination of employment, the lump sum actuarially
         equivalent value of the portion of a Participant's or Eligible
         Surviving Spouse's monthly benefits attributable to Employer
         Contributions does not exceed $3,500 ($5,000 effective October 1,
         2001), the Plan Committee, in its discretion, may direct that a lump
         sum payment equal to the lump sum actuarially equivalent value of such
         monthly benefits be paid to the Participant or Eligible Surviving
         Spouse. The lump sum actuarial equivalent value of the Participant's
         accrued benefits shall be determined as of the date of the distribution
         using the actuarial factors identified in Section 17.12(b).
         Notwithstanding the prior sentences, such a lump sum payment may not be
         made after the annuity starting date regardless of the present value of
         the nonforfeitable accrued benefit without appropriate Eligible
         Surviving Spouse's consent, if such benefit exceeded $3,500 ($5,000
         effective October 1, 2001) at the time of any prior distribution.

         A Participant who is re-employed by the employer after a termination of
         employment may repay any benefit he or she has received under the Plan
         before the earlier of five years after the first date on which the
         Participant is subsequently re-employed by the Employer or the close of
         the first period of five consecutive one-year breaks in service
         commencing after the Participant's withdrawal of benefits.

         Section 18.    Amendment of Section 9.8 of the Existing Plan. Effective
October 1, 2001, Section 9.8 is amended by deleting all of the second paragraph
thereof, except the first sentence.

         Section 19.    Amendment of Section 9.11(a) of the Existing Plan.
Effective January 1, 1999, Section 9.11(a) is amended by adding the following
phrase at the end of the last sentence thereof:

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         ; and any hardship distribution described in Code section
401(k)(2)(B)(i)(IV).

         Section 20.    Amendment of Section 12.5 of the Existing Plan.
Effective October 1, 2001, Section 12.5 is amended to read in its entirety as
follows:

         12.5     Plan Committee Decision Final. Subject to applicable law and
         the provisions of Section 12.6, any interpretation of the provisions of
         the Plan and any decision on any matter within the discretion of the
         Plan Committee made by the Plan Committee in good faith shall be
         binding on all persons. Benefits under this plan will be paid only if
         the Plan Committee decides in its discretion that the applicant is
         entitled to them. A misstatement or other mistake of fact shall be
         corrected when it becomes known and the Plan Committee shall make such
         adjustment on account thereof as it considers equitable and
         practicable.

         Section 21.    Amendment of Section 12 of the Existing Plan. Effective
October 1, 2001, Section 12 is amended by adding a new Section 12.9 thereto to
read in its entirety as follows:

         12.9     Electronic Administration. In its rules and procedures for
         the administration of the Plan, the Plan Committee may provide for the
         use of electronic communications and other media. Any reference in the
         Plan to forms shall mean either written forms or electronic forms, to
         the extent permitted by applicable law.

         Section 22.    Amendment of Section 17.12 of the Existing Plan.
Effective October 1, 2000, Section 17.12 is amended to read in its entirety as
follows:

         17.12    Actuarial Equivalent. Except to the extent expressly provided
         to the contrary by ERISA, a benefit shall be actuarially equivalent to
         any other benefit if the actuarial reserve required to provide the same
         is equal to the actuarial reserve required to provide such other
         benefit, computed on the basis of the actuarial rates, tables and
         procedures last adopted by the Plan Committee for this purpose. No
         adjustment in a determination of an actuarially equivalent value or
         amount shall be made if such tables, rates, and procedures are changed
         by the Plan Committee subsequent to such determination.

         (a)      In the case of determinations not subject to Code section
                  417(e)(3), actuarial equivalence shall be determined on the
                  basis of the following actuarial rates and tables:

                  (i)      The assumed mortality rate will be based on the 1971
                           Towers, Perrin, Forster and Crosby Forecast Mortality
                           Table using a one-year age setback for the
                           Participant and a five-year age setback for the
                           Beneficiary or spouse.

                  (ii)     In order to determine the equivalent value of
                           optional benefits, the assumed annual rate of return
                           will be 7%.

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         (b)      In the case of lump sum determinations, actuarial equivalence
                  shall be determined on the basis of the mortality table
                  prescribed by the Secretary of the Treasury in Rev. Rul. 95-6
                  (the "applicable mortality table") and the annual interest
                  rate for distributions during a Plan Year shall be the rate on
                  30-year Treasury securities in effect for the second month
                  preceding the first day of the Plan Year (i.e., August) (the
                  "applicable interest rate"). However, for distributions made
                  after October 1, 2000, and before the date that is one year
                  after the adoption date of this amendment, the interest rate
                  that would be used by the PBGC at the beginning of the Plan
                  Year for determining lump sum distributions on plan
                  termination shall be used if it results in a larger
                  distribution.

         (c)      In the case of distributions that are subject to Code section
                  417(e)(3), but which are not lump sums, actuarial equivalence
                  shall be determined on the basis of the actuarial factors
                  described in paragraph (a). However, in no event shall such
                  amounts be less than the amount calculated using the
                  applicable interest rate and applicable mortality table
                  described in paragraph (b) above.

         IN WITNESS WHEREOF, the Company has executed this instrument this
______ day of ___________ , 2002.

                                         STERLING CHEMICALS, INC.

                                         _______________________________________
                                         David G. Elkins, President and Co-Chief
                                               Executive Officer

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