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                                                                 Exhibit 10.2(a)

                            EQUISTAR CHEMICALS, LP
                                  BONUS PLAN

              (As Amended and Restated Effective January 1, 2000)


          Equistar Chemicals, LP (the "Company") has established a Bonus Plan
(the "Plan"), and hereby amends and restates the Plan effective as of January 1,
2000, in order to:

     .    Focus Participants on key measures of value creation for the Company's
          partners and on operating measures that lead to the creation of value.

     .    Provide significant upside and downside award potential commensurate
          with Company value creation.

     .    Encourage a long-term management perspective and reward for sustained
          long-term performance.

     .    Enhance the ability of the Company to attract and retain highly
          talented and competent individuals.

     .    Reinforce a team orientation among top management.

The Plan, as hereby amended and restated, shall apply to all payments made after
January 1, 2000, with respect to Awards granted prior to or after that date.

          1.   Definitions

          Award:  The amount payable under this Plan as determined by the
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     Committee according to the performance of the Company during the Plan Year.

          Award Percentage:  The percentage of the Participant's Base Salary
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     payable as a result of the Company's performance during the Plan Year,
     calculated in accordance with Section 7(a).

          Base Salary.  A Participant's annual base salary in effect on the last
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     day of the Plan Year.

          Committee: means the Compensation Committee of the Company's
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     Partnership Governance Committee.

          Disability: A permanent and total disability as defined in the
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     Company's Long-Term Disability Plan, if any, in which the Employee
     participates.
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          EBITDA: The Company's Earnings for the Plan Year before interest,
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     taxes, depreciation and amortization.

          EVA:  EVA is the economic value added as measured by the Company's
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     cash flow relative to the return that debt and equity holders expect to
     receive on the Company's capital.  Annual EVA is the difference between (i)
     cash generated by Company operations and (ii) the sum of the Company's debt
     and equity capital, multiplied by a factor representing investors' expected
     rate of return on that capital, as calculated under the formula in Schedule
     A.

          Financial Measures:  EVA, EBITDA and other objective measures of the
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     Company's financial and operational performance utilized by the Committee
     to evaluate the Company's performance over the Plan Year.

          Participant:  An Employee selected by the Committee to receive an
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     opportunity to earn an Award pursuant to the Plan.

          Performance Percentage:  The percentage designated by the Committee to
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     reflect the extent to which the Company attains its goals with respect to
     the Financial Measures.

          Plan Year:  The period from January 1 until December 31.
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          Retirement:  A termination of employment initiated voluntarily by the
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     Participant (i) on or after age 65 or (ii) on or after age 55 with 10 years
     of participation service as credited under the Company's qualified defined
     benefit pension plan.

          Target Bonus Percentage:  A percentage of the Participant's salary
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     determined by the Committee at the beginning of the Plan Year.

          Waiver and Release:  The legal document in which the Participant (or
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     the executor or administrator of the Participant's estate in the event of
     death), in exchange for amounts payable pursuant to Awards hereunder due to
     death, Disability or Retirement, releases the Company, its parents,
     subsidiaries and Related Entities (as defined in Section 8(d)(4)), their
     directors, officers, employees and agents, their employee benefit plans,
     and the fiduciaries and agents of said plans from liability and damages in
     any way related to the Participant's employment with or separation from the
     Company.  The Waiver and Release must be executed within 60 days after
     termination due to Disability or Retirement, or 180 days after termination
     due to death.

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          2.   Administration.

          The Plan is administered by the Committee.  All decisions of the
Committee shall be binding and conclusive on the Participants.  Subject to the
provisions of the Plan, the Committee shall have the authority to:

          (a)  Select the Participants;

          (b)  Determine the Financial Measures and Performance Percentage for
each Plan Year, and the Target Bonus Percentage and Award Percentage for each
Participant;

          (c)  Determine the amounts payable pursuant to Awards; and

          (d)  Establish from time to time policies and procedures for the
administration of the Plan, interpret the Plan, and make all determinations
necessary or advisable for the administration of the Plan.

          3.   Participation.  Participants are selected by the Committee.  No
Employee shall at any time have the right (a) to be selected as a Participant,
(b) if so selected, to be entitled to an Award except under the specific terms
set forth in the Plan, or (c) if selected as a Participant in this Plan Year, to
be selected as a Participant in any subsequent plan year. Participants will be
notified in writing of their selection as Participants.

          4.   Target Bonus Percentage.

          (a)  The Committee will assign each Participant a Target Bonus
Percentage for the Plan Year, based on the position level of each Participant
and other considerations as the Committee deems appropriate.  The Target Bonus
Percentage will be assigned within 90 days after the beginning of the Plan Year,
unless the Participant was not an Employee on the first day of the Plan Year.

          (b)  An Employee who becomes a Participant after the first day of the
Plan Year will be assigned a Target Bonus Percentage, and will be eligible for
an Award in the manner calculated pursuant to Section 8, but unless otherwise
determined by the Committee, such Award shall be prorated to reflect the number
of days in the Plan Year in which such individual was a Participant.

          5.   Financial Measures.  Within 90 days after the beginning of the
Plan Year, the Committee will establish one or more objective performance goals
for the Plan Year with respect to the Financial Measures.  The performance goals
for each Plan Year shall be communicated to each Participant.

          6.   Performance Percentage. Within 90 days after the beginning of the
Plan Year, the Committee will establish an objective methodology for determining
the Performance

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Percentage that will correspond with attained levels of performance under the
Financial Measures. Within 90 days following the end of the Plan Year, the
Committee will certify the Performance Percentage reached for the Plan Year.

          7.   Calculation of Awards.

          (a)  Each Participant's Award Percentage for the Plan Year will be
determined by multiplying the Participant's Target Bonus Percentage by the
Performance Percentage.

          (b)  Each Participant's Award payable for the Plan Year will be
determined by multiplying the Participant's Award Percentage by his or her Base
Salary.

          8.   Payment of Awards.

          The Committee has sole and absolute authority and discretion to
determine the time and manner in which Awards, if any, shall be paid under this
Plan.  The determination of the Committee, which shall be binding and conclusive
on any Participant, shall be communicated in writing to each Participant.
Generally, however, the following provisions apply:

          (a)  Form of Payment: Awards under the Plan are paid in the form of an
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annual cash payment (the "Annual Award") and a long-term payout (the "Long-Term
Award").  The Long-Term Award shall become outstanding upon payment of the
Annual Award and shall vest over three years at one-third each year, subject to
the adjustment in Subsection (c) below, commencing on March 31 of the following
year (or such earlier date as shall be determined by the Committee). Payments
will be paid in cash subject to adjustments for such federal, state or local
taxes and other deductions, if any, as may be in effect at the time of payment.

          (b)  Timing of Payment of Annual Awards: Annual Awards will be paid
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within 90 days after the close of the Plan Year.  Notwithstanding the foregoing,
a Participant may elect to defer amounts payable pursuant to an Award under the
terms of any deferred compensation plan in which he or she is eligible to
participate.

          (c)  Timing of Payment of Long-Term Awards: Long-Term Awards will be
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paid in three annual installments, beginning approximately one year after the
payment of the Annual Award.  Amounts payable under the Long-Term Awards may be
adjusted downward by up to 20% annually and may be adjusted upward by any
amount, in the discretion of the Committee, based on the results of EBITDA, EVA
or other Financial Measures determined by the Committee during the payment
period.  The Committee retains full discretion to determine whether any
adjustments will be made based on Financial Measures, and this discretion is in
addition to the general discretion retained by the Committee in Subsection (d).

          (d)  Termination, Death or Disability:  Except as indicated below and
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in Section 9, Annual Awards will be paid only to Participants who are actually
employed by and are on the payroll of the Company on the last day of the Plan
Year, and Long-Term Awards will be paid

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only to Participants who are actually employed by and are on the payroll of the
Company on the date payments are made.

               (1)  A Participant whose employment terminates for any reason
          other than the circumstances described in Subsection (e)(2) or (3)
          prior to the last day of the Plan Year, shall forfeit any and all
          Awards.

               (2)  Those Participants whose employment terminates due to death,
          Disability or Retirement prior to the end of the Plan Year will, upon
          timely execution of a Waiver and Release, be paid a pro-rata portion
          of their Annual Award based on the number of days in the Plan Year
          prior to their date of termination. Such prorated payments will be
          made at the time and in the form that all payments are normally made
          to all other Participants. Those Participants whose employment
          terminates due to death, Disability or Retirement after the end of the
          Plan Year but prior to the date of payment of such Annual Award will,
          upon timely execution of a Waiver and Release, receive the full amount
          of such Annual Award to which they would otherwise be entitled. Such
          payments shall be made at the time and in the form that all Annual
          Award payments are normally made to all other Participants.

               (3)  Those Participants whose employment terminates due to death,
          Disability or Retirement will, upon timely execution of a Waiver and
          Release, be paid the remaining installments of any outstanding Long-
          Term Awards.  Such payments will be made as soon as practicable after
          the date of termination and shall be made without the adjustment of
          Subsection (c) above.

               (4)  If at any time during the Plan Year, a Participant commences
          employment with Lyondell Chemical Company or its subsidiaries, or
          LYONDELL-CITGO Refining, LP (a "Related Entity"), the Participant's
          Award shall be pro-rated based upon the number of days in the Plan
          Year prior to commencement of employment with the Related Entity.
          Such payments shall be made at the time and in the form that all
          payments are normally made to all other Participants.

               (5)  If a Participant's employment terminates because of death,
          the Participant's beneficiary or beneficiaries, designated by the
          Participant for purposes of this Plan in the manner prescribed by the
          Committee, or if there is no such designation, under the Company's
          Group Life Insurance Plan, or in the absence of any such beneficiary,
          the Participant's surviving spouse, or if there is no surviving
          spouse, the personal representative of such Participant's estate will,
          upon timely execution of a Waiver and Release by the executor or
          administrator of the Participant's estate, be entitled to receive the
          Award to which the Participant was entitled under this Section 8(d).

               (6)  Notwithstanding any provision in this Section 8 or any other
          provision of the Plan to the contrary, for purposes of determining
          whether a

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          Participant has terminated employment hereunder, the employment of a
          Participant shall not be deemed to have been terminated because of his
          absence from active employment on account of temporary illness or
          during authorized vacation or during temporary leaves of absence,
          granted by the Company for reasons of professional advancement,
          education, health or government service, or during military leave for
          any period if the Participant returns to active employment within 90
          days after the termination of his military leave, or during any period
          required to be treated as a leave of absence by virtue of any valid
          law or agreement.

               (7)  Notwithstanding any other provision of the Plan, the
          Committee, in its sole discretion, may permit continued participation,
          pro-ration or early distribution with respect to Awards that would
          otherwise be forfeited pursuant to the terms of the Plan.

          9.   Assignments and Transfers.  A Participant shall not assign,
encumber or transfer his rights and interests under the Plan, other than
pursuant to a marital settlement agreement or similar domestic relations
agreement, decree or order, and any attempt to do so shall render those rights
and interests null and void.

          10.  Finality of Determinations.  Any determination by the Company or
the Committee in carrying out or administering this Plan shall be final and
binding for all purposes and upon all interested persons and their heirs,
successors, and personal representatives.

          11.  Employee Rights under the Plan.  Neither the Plan nor any action
taken thereunder shall be construed as giving an Employee any right to be
retained in the employ of the Company. No Participant shall have any lien on any
assets of the Company by reason of any Award under this Plan.

          12.  Amendment, Suspension or Termination.  The Committee may amend,
suspend or terminate the Plan in whole or in part at any time.


                                                          EQUISTAR CHEMICALS, LP

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