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                                                                    EXHIBIT 10.5

Lyondell Chemical Company
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EXECUTIVE DEFERRAL PLAN

Effective January 1, 2002
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                            Lyondell Chemical Company
                             Executive Deferral Plan

                                Table of Contents
                                -----------------

<TABLE>
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                                                                                                                 Page
<S>                                                                                                              <C>
ARTICLE I         ................................................................................................1
Section 1.1       Purpose and Intent of Plan......................................................................1
Section 1.2       Effective Date of Plan..........................................................................1
Section 1.3       Definitions.....................................................................................1

ARTICLE II        ................................................................................................5
Section 2.1       Eligibility and Participation...................................................................5
Section 2.2       Forms of Deferral...............................................................................5
Section 2.3       Deferral Elections..............................................................................5
Section 2.4       Limitation on Deferral..........................................................................5
Section 2.5       Termination of Employment.......................................................................6
Section 2.6       Transfers.......................................................................................6
Section 2.7       Modification of Deferral Elections..............................................................6

ARTICLE III       ................................................................................................7
Section 3.1       Accounts........................................................................................7
Section 3.2       Deferral Compensation...........................................................................7
Section 3.3       Interest Rate...................................................................................7
Section 3.4       Determination of Accounts.......................................................................7
Section 3.5       Vesting of Accounts.............................................................................8
Section 3.6       Statement of Accounts...........................................................................8

ARTICLE IV        ................................................................................................9
Section 4.1       Basic Plan Benefit..............................................................................9
Section 4.2       Form and Time of Retirement Distribution........................................................9
Section 4.3       Form of Distribution upon Termination of Employment............................................10
Section 4.4       Survivor Benefits..............................................................................10
Section 4.5       Early Distributions............................................................................12
Section 4.6       Unscheduled Distributions......................................................................13
Section 4.7       Disability.....................................................................................13
Section 4.8       Termination of Employment Due to Special Circumstances.........................................14
Section 4.9       Valuation and Settlement.......................................................................14
Section 4.10      Small Benefit..................................................................................14
Section 4.11      Benefits in the Event of a Change in Control...................................................14
Section 4.12      Events Constituting a Change in Control........................................................15
</TABLE>

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<TABLE>
<S>                                                                                                              <C>
ARTICLE V         ...............................................................................................18
Section 5.1       Designation of Beneficiary.....................................................................18
Section 5.2       Failure to Designate Beneficiary...............................................................18

ARTICLE VI        ...............................................................................................19
Section 6.1       Administrative Committee.......................................................................19
Section 6.2       Rules of Conduct; Administrative Provisions....................................................19
Section 6.3       Legal, Accounting, Clerical and Other Services.................................................19
Section 6.4       Interpretation of Provisions...................................................................19
Section 6.5       Records of Administration......................................................................19
Section 6.6       Denial of Claim................................................................................19
Section 6.7       Liability of Committee.........................................................................20

ARTICLE VII       ...............................................................................................21
Section 7.1       Amendment of Plan..............................................................................21
Section 7.2       Termination....................................................................................21
Section 7.3       Effect of Amendment or Termination.............................................................21

ARTICLE VIII      ...............................................................................................22
Section 8.1       Unfunded Benefit Plan..........................................................................22
Section 8.2       Unsecured General Creditor.....................................................................22
Section 8.3       Grantor Trust..................................................................................22
Section 8.4       Payments and Benefits Not Assignable...........................................................22
Section 8.5       No Right of Employment.........................................................................23
Section 8.6       Adjustments....................................................................................23
Section 8.7       Obligation to Company..........................................................................23
Section 8.8       Protective Provisions..........................................................................23
Section 8.9       Gender, Singular and Plural....................................................................23
Section 8.10      Law Governing..................................................................................24
Section 8.11      Notice.........................................................................................24
Section 8.12      Successors and Assigns.........................................................................24
Section 8.13      Provisions for Incapacity......................................................................24
</TABLE>

                                                                               2
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                                    ARTICLE I

                                GENERAL PROVISION

Section 1.1 Purpose and Intent of Plan.

     This Plan is intended to provide the opportunity for eligible Employees to
accumulate supplemental funds through the deferral of portions of their regular
salary, Awards and Executive Supplementary Savings Plan benefits for retirement
or special needs prior to retirement.

     This Plan is an amendment and restatement of the deferral provisions of the
Lyondell Chemical Company Executive Deferral Plan and Lyondell Chemical Company
Senior Manager Deferral Plan.

Section 1.2 Effective Date of Plan.

     This amended and restated Plan document shall be generally effective as of
January 1, 2002 and shall apply to those Employees who are employed by the
Company on or after January 1, 2002, except to the extent that certain
provisions hereof specify that they are effective as of a different date.

Section 1.3 Definitions.

     Account means a separate bookkeeping account maintained by the Company for
each Employee and which measures and determines the amounts to be paid to the
Employee under the Plan. Effective October 1, 1996, separate subaccounts for
previous deferrals of Salary, Awards or ESSP Benefits were consolidated into a
single account balance. Accounts also include any Transferred Accounts that were
assumed as obligations of this Plan as of October 1, 1990.

     Administrative Committee means the Benefits Administrative Committee of the
Company.

     Awards means immediate cash awards made under the Lyondell Chemical Company
annual incentive compensation plans for executives and senior managers or awards
under any other plan that the Board of Directors of Lyondell Chemical Company,
or its Compensation Committee, has authorized the Company to adopt and has
further authorized awards thereunder to be treated as Awards under this Plan.

     Beneficiary means a person who is entitled to receive an Employee's
interest under this Plan in the event of the Employee's death.

                                                                               1
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     Change in Control means a change in the control of Lyondell Chemical
Company as defined in Section 4.12 of the Plan.

     Code means the Internal Revenue Code of 1986, as amended, including any
successor provisions thereof and any regulations or other guidance promulgated
pursuant thereto by applicable governmental agencies.

     Company means Lyondell Chemical Company, a Delaware corporation, or its
successor.

     Deferral Election means an election made by an Employee to defer Salary,
Awards, and/or ESSP Benefits pursuant to Article II, for which the Employee has
submitted a Participation Agreement to the Company.

     Deferral Period means a maximum number of years, established by the
Administrative Committee in advance of a particular Deferral Election, over
which the Employee elects to defer Salary, Awards and/or ESSP Benefits. A new
Deferral Period shall normally start each January 1, except that an Employee who
is immediately eligible upon his commencement of employment or who otherwise
attains eligibility following the Effective Date, shall have his Deferral Period
commence 30 days following the Employee's first day of employment or attainment
of eligibility, as applicable.

     Deferred Compensation means the amount of Salary, Awards and/or ESSP
Benefits that a Participant elects to defer pursuant to a Deferral Election.

     Disability means the disability as determined under the provisions of the
Company's Executive Long-Term Disability Plan.

     Early Distribution means a distribution prior to Termination of Employment
pursuant to Section 4.5.

     Effective Date means January 1, 2002.

     Employee means an individual who is a regular salaried employee of the
Company on or after January 1, 2002.

     ERISA means the Employee Retirement Income Security Act of 1974, as
amended, including any successor provisions thereof, and any regulations or
other guidance promulgated pursuant thereto by applicable governmental agencies.

     ESSP Benefits means the benefits under the Company's Executive
Supplementary Savings Plan.

     Financial Hardship means a condition of financial difficulty, determined by
the Administrative Committee, upon advice of counsel, based on written
information supplied by the Employee in accordance with such standards
established by the Administrative Committee from

                                                                               2
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time to time, which condition is sufficient, in counsel's judgment, to justify a
change in payment election under the Plan without causing receipt of taxable
income by any other Plan Participant before the Participant actually receives
his benefit.

     Interest Rate means the interest rate announced by the Company in advance
of the election period for a Plan Year which shall be the interest rate applied
to that Plan year.

     Participant means any Employee who is participating in this Plan as
provided in Article II, and any former Employee who has not received the entire
benefit to which he is entitled under this Plan.

     Participation Agreement means the Deferral Election submitted by a
Participant to the Company prior to the beginning of the Deferral Period.

     Plan means this Executive Deferral Plan.

     Plan Year means each calendar year beginning on January 1 and ending on
December 31.

     Retirement Distribution means a distribution due to Termination of
Employment with a right to an immediate allowance under a retirement plan
maintained by the Company.

     Salary means the Employee's regular, biweekly salary, excluding Awards and
any other special or additional compensatory payments made by the Company.

     Subsidiaries or Affiliates means:

     (a) All corporations, that are members of a controlled group of
corporations within the meaning of Section 1563(a) of the Code (determined
without regard to Section 1563(a)(4) and Section 1563(e)(3)(C) of said Code) and
of which the Company is then a member, and

     (b) All trades or businesses, whether or not incorporated, that, under the
regulations prescribed by the Secretary of the Treasury pursuant to Section
210(d) of ERISA, are then under common control with the Company.

     Survivor Benefit means the benefit provided by Section 4.4 in the event of
the Participant's death.

     Termination of Employment means the termination of an Employee's employment
with Lyondell Chemical Company, LYONDELL-CITGO Refining LP, Equistar Chemicals,
LP or any subsidiary or affiliate of any such company. A transfer to any such
company, to which a Participant voluntarily consents, shall not be a Termination
of Employment for purposes of this Plan.

                                                                               3
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     Transferred Account means the portion of any Participant's Account that
reflect amounts of deferrals made by the Participant, plus any credited
interest, prior to October 1, 1990 under the Company's Annual Incentive Plan and
Executive Supplementary Savings Plan.

     Valuation Date means the last day of each month, or such other dates as the
Administrative Committee may determine in its discretion, which may be either
more or less frequent, for the valuation of Participants' Accounts.

                                                                               4
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                                   ARTICLE II

                     PARTICIPATION AND DEFERRAL COMMITMENTS

Section 2.1 Eligibility and Participation.

     (a) Eligibility. Eligibility to make a Deferral Election shall be limited
to Employees (1) who are eligible to receive an Award (2) who are Participants
in the Executive Supplementary Savings Plan or (3) who have been designated as
eligible by a specific resolution of the Administrative Committee upon
recommendation of the Senior Vice President and Chief Administrative Officer of
the Company.

     (b) Participation. An eligible Employee may elect to participate in the
Plan by submitting a Participation Agreement in accordance with rules, including
the time and form of submission, established by the Administrative Committee.

Section 2.2 Forms of Deferral.

     A Participant may elect to defer Salary, Awards and/or ESSP Benefits in a
Participation Agreement subject to any limitations, conditions or restrictions,
such as minimum or maximum amounts that may be deferred, as the Administrative
Committee prescribes in advance of the Deferral Period.

Section 2.3 Deferral Elections.

     Prior to each Deferral Period, at a time and on a form prescribed by the
Administrative Committee, each Employee may execute an election form to defer
Salary, Awards, and/or ESSP Benefits. This Deferral Election shall be
irrevocable unless modifications are authorized pursuant to Section 2.7.

Section 2.4 Limitation on Deferral

     Except as permitted for accelerated deferral in Section 2.7(b), Deferral
Elections shall be subject to the following limitations:

     (a) A Participant may not defer more than 50 percent of his Salary.

     (b) The minimum amount that may be deferred for the Deferral Period
relating to a Deferral Election shall be established by the Administrative
Committee in advance of the Deferral Period.

                                                                               5
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Section 2.5 Termination of Employment.

     A Participant's Deferral Elections shall terminate upon the Participant's
Termination of Employment; provided, however, that any Deferral Election
                           --------  -------
relating to Salary, Awards and/or ESSP Benefits granted after Termination of
Employment shall remain binding.

Section 2.6 Transfers.

     A Participant's Deferral Elections shall be irrevocable regardless of a
transfer of employment among Lyondell Chemical Company, LYONDELL-CITGO Refining
LP, Equistar Chemicals, LP or any subsidiary or affiliate of any such company.
In the case of such a transfer, other than a transfer to Equistar Chemicals, LP
as a result of the formation of Equistar Chemicals, LP, the Participant's
Deferral Election shall apply to Awards, Salary or ESSP Benefits granted by the
transferee company and the applicable Plan of the transferee company shall
assume responsibility for the remaining period, if any, of any Deferral Election
that the Participant made under the transferor company's plan.

Section 2.7 Modification of Deferral Elections.

     Deferral Elections shall be irrevocable except as follows:

     (a) Financial Hardship. The Administrative Committee may permit a
Participant to either reduce the amount elected under a prior Deferral Election,
or waive the remaining deferrals under a prior Deferral Election, upon finding
that the Participant has suffered a Financial Hardship.

     (b) Accelerated Deferral. At the Administrative Committee's discretion,
prior to the beginning of any Plan Year in any Deferral Period for which two or
more Plan Years remain, a Participant may elect to accelerate the amount of
previously elected Deferred Compensation for any of the remaining Plan Years in
that Deferral Period on a form prescribed by the Administrative Committee;
provided, however, that any acceleration in Deferred Compensation for remaining
-------- --------
Plan Years in the Deferral period shall not increase, for any single Plan Year,
the total Salary deferrals above 50 percent of Salary, the total deferred Awards
above 100 percent of an Award or the total deferred ESSP Benefits above 100
percent of the ESSP Benefits during that Plan Year.

                                                                               6
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                                   ARTICLE III

                         DEFERRED COMPENSATION ACCOUNTS

Section 3.1 Accounts.

     For record-keeping purposes only, Accounts shall be maintained for each
Participant.

Section 3.2 Deferred Compensation.

     A Participant's Deferred Compensation shall be credited to the
Participant's Account as of the date when the corresponding non-deferred portion
of the compensation is paid or would have been paid but for the Deferral
Election. The Company shall have the right to withhold from Salary (or otherwise
to cause the Employee or the executor or administrator of his estate, or his
Beneficiary) to make payment of any federal, state, local and/or foreign taxes
required to be withheld with respect to any Deferred Compensation.

Section 3.3 Interest Rate.

     The Accounts shall be credited with interest based on the rates specified
below. Interest shall be credited monthly as of each Valuation Date from the
dates when deferred amounts are credited to Accounts, based on the balance of
each Account.

     (a) Interest Rate During Participant's Lifetime. During a Participant's
lifetime, the Participant's Account will be credited with interest on a monthly
basis during each Plan Year at the Interest Rate previously announced by the
Company to apply during the Plan Year. The monthly Interest Rate during the Plan
Year shall be based on the previous monthly average of the Salomon Brothers
Corporate BB Bond Yield.

     (b) Interest Rate After Participant's Death. Except with respect to
payments made pursuant to Article IV, Section 4.4(a)(2)(i) following a
Participant's death, the Participant's Account will be credited with interest on
a monthly basis during each Plan Year at the Interest Rate previously announced
by the Company to apply during the Plan Year.

Section 3.4 Determination of Accounts.

     A Participant's Account as of each Valuation Date shall consist of the
balance of the Participant's Account as of the immediately preceding Valuation
Date, plus the amount of the Participant's Deferred Compensation since Valuation
Date, plus interest credited to the Account, and minus any distributions or
reductions made from the Account since the immediately preceding Valuation Date.

                                                                               7
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Section 3.5 Vesting of Accounts.

     Each Participant shall be 100 percent vested at all times in the amounts
credited to the Participant's Account.

Section 3.6 Statement of Accounts.

     The Company shall provide each Participant with periodic statements setting
forth the balance of the Participant's Account.

                                                                               8
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                                   ARTICLE IV

                                  PLAN BENEFITS

Section 4.1 Basic Plan Benefit.

     If a Participant has a Termination of Employment for any reason, the
Company shall pay a Plan benefit equal to the Participant's Account, as
determined below:

     (a) Accounts of Participants shall be credited with the interest rate
previously determined under Section 3.3(a) and communicated in advance of each
deferral Period, to apply each Plan Year that the Account has been maintained.

     (b) Except as provided in Section 4.11, the Interest Rates provided under
Section 4.1(a) shall be payable until the Participant's Account is distributed
in full.

Section 4.2 Form and Time of Retirement Distribution.

     (a) Time of Retirement Distributions. Retirement Distributions shall be
paid at the time and in the form of benefit elected by the Participant. If a
Participant is an Employee, the Participant may change a distribution election
once each year until the year in which the Participant attains age 53. The
change must be made during a period established by the Administrative Committee
which precedes a Deferral Period and is irrevocable until the next period
established by the Administrative Committee.

     The Participant's distribution election shall be irrevocable as of the year
in which a Participant attains age 53, except that a Participant may request, in
writing, that the Administrative Committee allow a change in distribution
election prior to retirement or commencement of benefits, or in the case of
installment payments, following commencement of payments, (i) without any
reduction in, or imposition of any penalty on, the Participant's Account, if the
Administrative Committee determines that the Participant has experienced a
Financial Hardship justifying the request for a change of election, or (ii) if
the Administrative Committee, in its sole discretion, determines that it is
appropriate to grant the Participant's request. Absent the Participant's
election of the form and/or commencement date of the Retirement Distribution,
payment will be made in a lump sum immediately following the Participant's date
of retirement from the Company.

     (b) Form of Retirement Distributions. A Participant may elect one or more
of the following forms and commencement dates for all or portions of his
Deferral Account:

          (1) Lump Sum. A single payment of all or a percentage of, or of a
specific dollar amount of, the Participant's Deferral Account, payable at
retirement.

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          (2) Installment Payments. Monthly installment payments in
substantially equal payments of principal and interest over periods prescribed
and communicated by the Administrative Committee in advance of the applicable
Deferral period. The amount of each of the monthly installments shall be
redetermined effective as of January 1 of each year based on the remaining
Account balance and the remaining number of installment payments.

          (3) Deferred Payments. A lump sum or installment payments or
combination thereof, commencing subsequent to retirement at one of the optional
deferral times prescribed and communicated by the Administrative Committee in
advance of the applicable Deferral Period.

Section 4.3 Form of Distribution Upon Termination of Employment.

     Except as provided in Sections 4.8 and 4.11, termination benefits payable
upon a Participant's Termination of Employment other than due to retirement or
death shall be paid in a lump sum following Termination of Employment; provided,
however, that the Administrative Committee may, in its sole discretion, pay such
termination benefits in monthly installments over a 3-year period.

Section 4.4 Survivor Benefits.

     (a) Amount and Form of Benefit

          (1) Death After Age 65. If the Participant dies on or after attaining
age 65, the amount of the Survivor Benefit shall be equal to the Participant's
Account balance, increased by the applicable Interest Rate on the unpaid Account
balance during the period in which Survivor Benefit payments are being made to
the Participant's Beneficiary, and payable in the form elected by the
Participant.

          (2) Death Prior to Termination of Employment and Prior to Age 65.

               (i) Benefit Determination. If a Participant dies prior to
attaining age 65 and prior to Termination of Employment, the Survivor Benefit
payable with respect to such Participant shall be the greater of the values
determined under (A) or (B) immediately below:

                    (A) The net present value of a stream of annual payments
which equals 40 percent of the Participant's Account, and which are payable on
the date of the Participant's death and on each anniversary of such date until
the date on which the Participant would have attained age 65. For purposes of
this calculation (I) the applicable discount rate shall be determined by the
Administrative Committee, in its sole discretion, and (II) Deferral Elections
that have not been completed prior to the Participant's death shall be
determined in accordance with the provisions of Section 4.4(a)(2)(i)(c) below;
or

                    (B) The value of the Participant's Account balance at his
date of death.

                                                                              10
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                    (C) For purposes of calculating the deferred amount where a
Participant has died before he completes his Deferral Elections, the
Participant's Salary (for purposes of determining the amount deferred with
respect to either Salary or ESSP Benefits) and Awards for relevant years or
other time periods ending after this death shall be deemed to be as follows:

                              (I) Salary for each year or time period shall be
               the Participant's annual base Salary in effect on the date of his
               death, increased for each year after his death by the escalation
               factor for such year, determined in the sole discretion of the
               Administrative Committee; and

                              (II) Awards for each such year shall be the amount
               that is the highest annual average of the Participant's Awards
               paid in any 3 consecutive year period during the last ten years
               during which the Participant received Awards from the Company or,
               for years prior to the Effective Date, from a Subsidiary or
               Affiliate (or if fewer than ten, the total number of years for
               which the Participant received Awards).

               (ii) Amount and Form of Payment.

                               (A) The annual Survivor Benefit payable with
respect to Section 4.4(a)(2)(i)(A) shall be equal to 40 percent of the value of
the Account, as determined in accordance with Section 4.4(a)(2)(i)(A) and, to
the extent applicable, with Section 4.4(a)(2)(i)(C). One-twelfth of the annual
Survivor Benefit shall be paid monthly from the Participant's date of death
until the end of the month in which the Participant would have attained age 65.

                              (B) The Survivor Benefit payable with respect to
Section 4.4(a)(2)(i)(B) shall be the value of the Participant's Account balance
at his date of death, increased by the applicable Interest Rate on the unpaid
Account balance during the period in which Survivor Benefit payments are being
made to the Participant's Beneficiary, and shall be paid in monthly installments
over the greater of:

                                    (I) the period described in Section
               4.4(a)(2)(ii)(A); or

                                    (II) the period over which the Participant
               had elected to have installment payments made after his
               retirement.

                              (C) Notwithstanding any other provision of this
Plan, if the Survivor Benefit payable is the amount determined under Section
4.4(a)(2)(ii)(A), and if the Participant completed (or, pursuant to Section
4.4(a)(2)(i)(C), is deemed to have completed) a portion of a Deferral Election
while an employee at LYONDELL-CITGO Refining LP and a portion of such Deferral
Election while a Participant in this Plan, then the annual amount of the
Survivor Benefit determined pursuant to Section 4.4(a)(2)(ii)(A) shall be equal
to the product of (I) the amount of

                                                                              11
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the Survivor Benefit determined pursuant to Section 4.4(a)(2)(ii)(A), multiplied
by (II) a fraction, the numerator of which is equal to the portion of the
Deferral Elections that the Participant completed (or, pursuant to Section
4.4(a)(2)(i)(C), is deemed to have completed) under this Plan and the
denominator of which is equal to the sum of the Deferral Election that the
Participant completed (or, pursuant to Section 4.4(a)(2)(i)(C) is deemed to have
completed) under this Plan and under the LYONDELL-CITGO Refining LP Executive
Deferral Plan. An example of the determination of the Survivor Benefit and the
proration of that Benefit between the Company and LYONDELL-CITGO Refining LP is
attached hereto as Appendix A.

     (b) Death After Termination of Employment and Prior to Age 65. If the
Participant dies after Termination of Employment and prior to age 65, the
Participant's Account balance shall be paid by continuation of the form of
benefit that was payable to the Participant for the remaining payments that
would have been made to the Participant if the Participant had lived, increased
by the applicable Interest Rate credited on unpaid Account balances of deceased
Participants during each year of the payment period to the Beneficiary.

     (c) Death Following Change in Control. If a Participant is entitled to a
payment under Section 4.11 and dies prior to receiving his entire Account, the
balance of the Participant's Account shall be paid to Participant's Beneficiary
in a lump sum or on an installment basis, according the Participant's election
of form of payment on Change in Control.

Section 4.5 Early Distributions.

     A Participant may elect to receive an Early Distribution from his Account
subject to the following restrictions:

     (a) Timing of Election. The election to take an Early Distribution from an
Account for a particular Deferral Election must be made at the same time the
Participant makes the particular Deferral Election.

     (b) Amount of Withdrawal. The amount which a Participant can elect to
receive as an Early Distribution with respect to an Account shall be such
portions of the Participant's Account balance for the amounts deferred under a
particular Deferral Election, as prescribed by the Administrative Committee in
advance of the Deferral Period. If a previously elected amount exceeds the
Account balance when an Early Distribution is to be made, only the Account
balance will be paid.

     (c) Timing and Form of Early Distribution. The Early Distribution shall
commence at a time prescribed by the Administrative Committee and in the form
elected by the Participant on the Participation Agreement at the time of the
Deferral Election; provided, however, that if the Participant terminates
                   --------  -------
employment without a right to commence a retirement allowance under the
Retirement Plan, the Early Distribution election will be canceled and
distribution will be made pursuant to Section 4.3; and provided, further, that
                                                       --------  -------
if the Participant terminates employment with a right to commence a retirement
allowance, the Early Distribution election will be canceled and distribution
will be made pursuant to Section 4.2.

                                                                              12
<PAGE>

     (d) Amounts paid to a Participant pursuant to this section shall be treated
as distributions from the Participant's Account.

Section 4.6 Unscheduled Distributions.

     (a) Distributions on Account of Financial Hardship. Upon a finding that a
Participant has suffered a Financial Hardship, following the Participant's
written application, the Administrative Committee shall make a distribution of
all or a portion of the Participant's Account, consistent with the finding of
Financial Hardship but not to exceed the amount of the Participant's request,
without any reduction in, or imposition of any penalty on, the Participant's
Account. The distribution shall be paid in a lump sum as soon as
administratively practical following the finding of Financial Hardship.

     (b) Other Unscheduled Distributions. A Participant, by a written
application to the Administrative Committee, may apply for a distribution of all
or part of his/her Account, without regard to any condition of Financial
Hardship. Any distribution so requested shall be made as soon as practical
following the Participant's application and shall be subject to whatever
penalty, in the form of a forfeiture of a percentage of the amount requested
and/or a suspension of participation, as may be determined by the Administrative
Committee, upon the advice of Counsel for the Plan, to be necessary to preclude
the constructive receipt of taxable income by any Participant in the Plan.

     (c) Review of the Request for Unscheduled Distributions. Counsel for the
Plan, on an ongoing basis, shall review legal and tax developments to assure
continuous compliance with the relevant authorities governing plan design to
prevent constructive receipt of taxable income by any Participant, and shall
advise the Administrative Committee in writing in advance of any change in its
most recent written advice on the penalty that is to be imposed with respect to
unscheduled distributions.

     The Company shall notify Participants in writing of the provisions of this
Section 4.6 and of the specific, currently effective penalty as described under
Section 4.6(b), and shall update this written notification periodically and in
advance of any subsequent change of which it is notified under Section 4.6(c),
unless in the opinion of the Company it is administratively impractical to do
so, in which case such notification shall be provided no later than30 days
following the effective date of the change.

Section 4.7 Disability.

     If a Participant suffers a Disability under the provisions of the Company's
Executive or regular Long-Term Disability Plan, the Participant's Deferral
Elections will cease except for any awards that may be payable thereafter.
Distribution of the Participant's Account will not be made due to the
Disability. The Participant's Account will be distributed in accordance with the
method that the Participant had elected for payment of retirement benefits if
and when the

                                                                              13
<PAGE>

Participant retires following his Disability. Absent the Participant's
retirement election, payment will be made in a lump sum upon Termination of
Employment.

Section 4.8 Termination of Employment Due to Special Circumstances.

     If, other than as provided in Section 4.11, a Participant has an
         ----- ----
involuntary Termination of Employment in conjunction with a sale of assets or a
reorganization (including termination due to a specific job elimination), the
Participant's Account will be distributed in accordance with the method which
the Participant had elected for payment of retirement benefits under this Plan,
with payment commencing on the earliest date the Participant would have become
eligible to commence receiving the retirement benefit hereunder. During the
period between the Participant's Termination of Employment and the commencement
of payments under this Plan, interest will be credited to the Participant's
Account each year at the applicable rate of interest for Accounts of living
Participants. Absent the Participant's election with respect to the form of
benefit to be paid by this Plan at or after his retirement, payment will be made
in a lump sum upon Termination of Employment.

Section 4.9 Valuation and Settlement.

     The Settlement Date shall be the earlier of the date on which a lump sum is
paid or on which installment payments commence. The Settlement Date for an
Account shall be no more than 30 days after the last day of the month in which
the Participant or his Beneficiary becomes entitled to payments on account of
retirement, other Termination of Employment or death, unless the Participant has
elected to defer commencement of payments following retirement to a later date.
The Settlement Date for an Early Distribution or delayed payments following
retirement shall be the month that the Participant has elected for commencement
of such payments. The amount of a lump sum and the initial amount of installment
payments for a Participant's Account shall be based on the value of the
Participant's Account as of the valuation Date at the end of the immediately
preceding month before the Settlement Date. For example, the Valuation Date at
the end of December shall be used to determine a lump sum and/or the initial
amount of installment payments that will be made in the following January.

Section 4.10 Small Benefit.

     Notwithstanding any election made by the Participant, the Administrative
Committee, in its sole discretion, may pay any benefit in the form of a lump sum
payment to the Participant or any Beneficiary, if the lump sum amount of the
Account balance that remains in the Account following a distribution for any
reason, or which is payable to the Participant or Beneficiary when payments to
such Participant or Beneficiary would otherwise commence is less than $6,000.

Section 4.11 Benefits In the Event of a Change in Control.

     Notwithstanding the contrary provisions of Section 4.8, the provisions of
this Section 4.11 shall control in the event of Change in Control of the
Company.

                                                                              14
<PAGE>

     In the event of a Change in Control, as defined in Section 4.12, the full
amount of contributions and earnings accrued or credited to the Participant's
Account (as of the date immediately preceding the Change in Control) shall be
distributed to the Participant or the Participant's Beneficiary, if a Survivor
Benefit is being paid at the time of the Change in Control. Payment shall be
made in a form previously approved by the Administrative Committee and
previously elected by the Participant.

Section 4.12 Events Constituting a "Change in Control". For purposes of this
Plan, a Change in Control shall be deemed to have occurred as of the date that
one or more of the following occurs:

     (i) Individuals who, as of February 1, 1999, constitute the entire Board
("Incumbent Directors") cease for any reason to constitute at least a majority
of the Board; provided, however, that any individual becoming a director
              -------- --------
subsequent to the date hereof whose election, or nomination for election by the
Company's shareholders, was approved by a vote of at least a majority of the
then Incumbent Directors shall be considered as though such individual was an
Incumbent Director, but excluding, for this purpose any such individual whose
initial assumption of office occurs as a result of either an actual or
threatened election contest, as such terms are used in Rule 14a-11 under the
Securities Exchange Act of 1934, as amended or other actual or threatened
solicitation of proxies or consents by or on behalf of any Person (as defined
below) other than the Board;

     (ii) The stockholders of the Company shall approve any merger,
consolidation or recapitalization of the Company (or, if the capital stock of
the Company is affected, any subsidiary of the Company), or any sale, lease, or
other transfer (in one transaction or a series of transactions contemplated or
arranged by any party as a single plan) of all or substantially all of the
assets of the Company (each of the foregoing being an "Acquisition Transaction")
where (1) the shareholders of the Company immediately prior to such Acquisition
Transaction would not immediately after such Acquisition Transaction
beneficially own, directly or indirectly, shares or other ownership interests
representing in the aggregate eighty percent (80%) or more of (a) the then
outstanding common stock or other equity interests of the corporation or other
entity surviving or resulting from such merger, consolidation or
recapitalization or acquiring such assets of the Company, as the case may be, or
of its ultimate parent corporation or other entity, if any (in either case, the
"Surviving Entity"), and (b) the Combined Voting Power of the then outstanding
Voting Securities of the Surviving Entity or (2) the Incumbent Directors at the
time of the initial approval of such Acquisition Transaction would not
immediately after such Acquisition Transaction constitute a majority of the
Board of Directors, or similar managing group, of the Surviving Entity;
provided, however, that, notwithstanding the foregoing, a Change of Control
--------  -------
shall not be deemed to have occurred for purposes of this Subsection (ii) if
each of the following conditions are met: (a) the Acquisition Transaction is
between the Company and/or its Affiliates, on the one hand, and Millennium
Chemicals Inc. ("Millennium") and/or its Affiliates, on the other hand, (b) the
Company or an entity that was a wholly owned subsidiary of the Company prior to
the Acquisition Transaction has a class of equity securities registered under
Section 12 of the Securities Exchange Act of 1934, as amended, immediately after
completion of the Acquisition Transaction, (c) Millennium or an entity that was
a wholly owned subsidiary of Millennium prior to the Acquisition Transaction has
a class of equity securities registered under Section 12 of the Securities
Exchange Act of 1934, as amended, immediately after completion of

                                                                              15
<PAGE>

the Acquisition Transaction, and (d) as a result of the Acquisition Transaction,
the Company or its Affiliates own a greater percentage equity interest in
Equistar Chemicals, LP ("Equistar") than was owned, directly or indirectly, by
the Company immediately prior to such Acquisition Transaction;

     (iii) The stockholders of the Company shall approve any plan or proposal
for the liquidation or dissolution of the Company; or

     (iv) Any Person shall be or become the beneficial owner (as defined in
Rules 13d-3 and 13d-5 under the Securities Exchange Act of 1934, as amended),
directly or indirectly, of securities of the Company representing in the
aggregate more than twenty percent (20%) of either (A) the then outstanding
shares of common stock of the Company ("Common Shares") or (B) the Combined
Voting Power of all then outstanding Voting Securities of the Company; provided,
                                                                        --------
however, that notwithstanding the foregoing, a Change in Control shall not be
-------
deemed to have occurred for purposes of this Subsection (iv):

          (1) Solely as a result of an acquisition of securities by the Company
     which, by reducing the number of Common Shares or other Voting Securities
     outstanding, increases (a) the proportionate number of Common Shares
     beneficially owned by any Person to more than twenty percent (20%) of the
     Common Shares then outstanding, or (b) the proportionate voting power
     represented by the Voting Securities beneficially owned by any Person to
     more than twenty percent (20%) of the Combined Voting Power of all then
     outstanding Voting Securities;

          (2) Solely as a result of an acquisition of securities directly from
     the Company, except for any conversion of a security that was not acquired
     directly from the Company; or

          (3) Solely as a result of a direct or indirect acquisition by
     Occidental Petroleum Corporation ("Occidental") or Millennium, or any
     Affiliate of either of them, of beneficial ownership of securities
     representing, (x) in the case of Occidental (with its Affiliates), no more
     than forty percent (40%), (y) in the case of Millennium (with its
     Affiliates), no more than forty percent (40%), and (z) in the case of
     Occidental (with its Affiliates) and Millennium (with its Affiliates) in
     the aggregate, no more than forty-nine percent (49%), of either (A) the
     then outstanding Common Shares or (B) the Combined Voting Power of all then
     outstanding Voting Securities of the Company, pursuant to or as
     contemplated under any agreement between the Company and Occidental and/or
     Millennium or Affiliates of either of them (including any subsequent
     related transaction or series of related transactions or acquisitions of
     Voting Securities of the Company by Occidental and/or Millennium or their
     Affiliates or assignees approved by the Incumbent Directors prior to the
     consummation of such transaction or series of related transactions) where,
     as a result of such transaction or series of related transactions, the
     Company or a Surviving Entity owns, directly or indirectly, a greater
     percentage equity interest in

                                                                              16
<PAGE>

     Equistar than was owned, directly or indirectly, by the Company
     immediately prior to such transaction or series of related transactions;

     provided, further, that if any Person referred to in paragraph (1) or (2)
     of this Subsection (iv) shall thereafter become the beneficial owner of
     additional shares or other ownership interests representing one percent
     (1%) or more of the outstanding Common Shares or one percent (1%) or more
     of the Combined Voting Power of the Company (other than (x) pursuant to a
     stock split, stock dividend or similar transaction or (y) as a result of an
     event described in paragraph (1), (2) or (3) of this Subsection (iv)), then
     a Change in Control shall be deemed to have occurred for purposes of this
     Subsection (iv).

     (v) For purposes of this definition of Change in Control, the following
capitalized terms have the following meanings:

          (1) "Affiliate" shall mean, as to a specified person, another person
     that directly, or indirectly through one or more intermediaries, controls
     or is controlled by, or is under common control with, the specified person,
     within the meaning of such terms as used in Rule 405 under the Securities
     Act of 1933, as amended, or any successor rule.

          (2) "Combined Voting Power" shall mean the aggregate votes entitled to
     be cast generally in the election of the Board of Directors, or similar
     managing group, of a corporation or other entity by holders of then
     outstanding Voting Securities of such corporation or other entity.

          (3) "Person" shall mean any individual, entity (including, without
     limitation, any corporation, partnership, trust, joint venture, association
     or governmental body) or group (as defined in Sections 14(d)(3) or 15(d)(2)
     of the Exchange Act and the rules and regulations thereunder); provided,
                                                                    ---------
     however, that Person shall not include the Company, LYONDELL-CITGO Refining
     -------
     LP ("LCR") or Equistar, any of their subsidiaries, any employee benefit
     plan of the Company, LCR or Equistar or any of their majority-owned
     subsidiaries or any entity organized, appointed or established by the
     Company, LCR, Equistar or such subsidiaries for or pursuant to the terms of
     any such plan.

          (4) "Voting Securities" shall mean all securities of a corporation or
     other entity having the right under ordinary circumstances to vote in an
     election of the Board of Directors, or similar managing group, of such
     corporation or other entity.

                                                                              17
<PAGE>

                                    ARTICLE V

                           DESIGNATION OF BENEFICIARY

Section 5.1 Designation of Beneficiary.

     Each Participant shall have the right to designate a Beneficiary or
Beneficiaries to receive his interest in his Account upon his death. Such
designation shall be made on a form prescribed by and delivered to the Company.
The Participant shall have the right to change or revoke any such designation
from time to time by filing a new designation or notice of revocation with the
Company, and no notice to any Beneficiary nor consent by any Beneficiary shall
be required to effect any such change or revocation.

Section 5.2 Failure to Designate Beneficiary.

     If a Participant fails to designate a Beneficiary before his death, or if
no designated Beneficiary survives the Participant, the Administrative Committee
shall direct the Company to pay the balance in his Account in a lump sum to the
executor or administrator for his estate.

                                                                              18
<PAGE>

                                   ARTICLE VI

                                 ADMINISTRATION

Section 6.1 Administrative Committee.

     The Benefits Administrative Committee for the Company shall act as this
Plan's Administrative Committee.

Section 6.2 Rules of Conduct; Administrative Provisions.

     The Administrative Committee shall adopt such rules for the conduct of its
business and the administration of this Plan as it considers desirable;
provided, however, that such rules shall not conflict with the provisions of
this Plan. Except as otherwise specifically provided in this Plan, all of the
administrative provisions (such as the benefit claims procedures) contained in
the 401(k) and Savings Plan shall apply to the administration of this Plan.

Section 6.3 Legal, Accounting, Clerical and Other Services.

     The Administrative Committee may authorize one or more of its members or
any agent to act on its behalf and may contract for legal, accounting, clerical
and other services to carry out this Plan. All expenses of the Administrative
Committee shall be paid by the Company.

Section 6.4 Interpretation of Provisions.

     The Administrative Committee shall have the exclusive right and
discretionary authority to interpret the provisions of this Plan and to decide
questions arising in its administration. The decisions and interpretations of
the Administrative Committee shall be final and binding on the Company,
Employees and all other persons.

Section 6.5 Records of Administration.

     The Administrative Committee shall keep records reflecting the
administration of this Plan which shall be subject to audit by the Company.

Section 6.6 Denial of Claim.

     The Administrative Committee shall provide adequate notice in writing to
any Employee or Beneficiary whose claim for benefits under this Plan has been
denied, setting forth the specific reasons for such denial. The Employee or
Beneficiary will be given an opportunity for a full and fair review by the
Administrative Committee of the decision denying the claim. The Employee

                                                                              19
<PAGE>

or Beneficiary shall be given 60 days from the date of the notice denying any
such claim within which to request such review.

Section 6.7 Liability of Committee.

     No member of the Administrative Committee shall be liable for any action
taken in good faith or for exercise of any power given the Administrative
Committee, or for the actions of other members of said Committee.

                                                                              20
<PAGE>

                                   ARTICLE VII

                          AMENDMENT AND DISCONTINUANCE

Section 7.1 Amendment of Plan.

     This Plan may be amended from time to time by the Compensation Committee of
the Board of Directors of the Company.

Section 7.2 Termination.

     The Company intends to continue this Plan indefinitely, but reserves the
right to terminate it at any time for any reason.

Section 7.3 Effect of Amendment or Termination.

     No amendment or termination of this Plan may adversely affect the benefit
payable to any former Employee receiving benefits under this Plan prior to the
effective date of the amendment or termination, or any Employee who, as of such
date, was eligible to receive a benefit under this Plan.

                                                                              21
<PAGE>

                                  ARTICLE VIII

                                  MISCELLANEOUS

Section 8.1 Unfunded Benefit Plan.

     This Plan is intended to constitute a plan which is unfunded and maintained
primarily for the purpose of providing deferred compensation in the form of
additional retirement benefits to a select group of management or highly
compensated employees, as defined in Section 201(a)(2), 301(a)(3) and 401(a)(1)
of ERISA.

Section 8.2 Unsecured General Creditor.

     Participants and their Beneficiaries shall have no legal or equitable
rights, claims or interests in any specific assets or property of the Company,
nor shall they be the Beneficiaries of, or have any rights, claims or interests
in any life insurance policies, annuity contracts, or the proceeds therefrom
owned, or which may be acquired by, the Company (the "Policies"). Any such
Policies or other assets of the Company shall be, and remain, the general,
unpledged, unrestricted assets of the Company. The Company's obligation under
the Plan shall be merely that of an unfunded and unsecured promise of the
Company to pay money in the future.

Section 8.3 Grantor Trust.

     Although the Company is responsible for the payment of all benefits under
the Plan, the Company may, in its discretion, contribute funds to a grantor
trust for the purpose, as it deems appropriate, of paying benefits under this
Plan. Such trust may be irrevocable, but assets of the trust shall be subject to
the claims of creditors of Lyondell Chemical Company. To the extent any benefits
provided under the Plan are actually paid from the trust, the Company shall have
no further obligation with respect thereto but to the extent not so paid, such
benefits shall remain the obligation of, and shall be paid by, the Company. The
Employees shall have the status of unsecured creditors insofar as their legal
claim for benefits under the Plan and the Employees shall have no security
interest in the grantor trust.

Section 8.4 Payments and Benefits Not Assignable.

     Payments to and benefits under this Plan are not assignable, transferable
or subject to alienation since they are primarily for the support and
maintenance of the Participants and their joint annuitants or Beneficiaries
after retirement. Likewise, such payments shall not be subject to attachments by
creditors of, or through legal process against, the Company, the Administrative
Committee or Participant.

                                                                              22
<PAGE>

Section 8.5 No Right of Employment.

     The provisions of this Plan shall not give an Employee the right to be
retained in the service of the Company nor shall this Plan or any action taken
under the Plan be construed as a contract of employment.

Section 8.6 Adjustments.

     At the Company's request, the Administrative Committee may, with respect to
a Participant, adjust such Participant's benefit under this Plan or make such
other adjustments with respect to such Participant as are required to correct
administrative errors or provide uniform treatment of Participants in a manner
consistent with the intent and purpose of this Plan.

Section 8.7 Obligation to Company.

     If a Participant becomes entitled to a distribution of benefits under the
Plan, and if at such time the Participant has outstanding any debt, obligation,
or other liability representing an amount owing to the Company, or any benefit
plan maintained by the Company, then the Company may offset such amount owed to
it or such benefit plan against the amount of benefits otherwise distributable.
Such determination shall be made by the Administrative Committee.

Section 8.8 Protective Provisions.

     Each Participant shall cooperate with the Company by furnishing any and all
information requested by the Company in order to facilitate the payment of
benefits hereunder, taking such physical examinations as the Company may deem
necessary and taking such other relevant action as may be requested by the
Company. If a Participant refuses to cooperate, the Company shall have no
further obligation to the Participant under the Plan. If the Participant makes
any material misstatement of information or nondisclosure of medical history,
then no benefits will be payable hereunder to such Participant or his
Beneficiary, provided, that in the Company's sole discretion, benefits may be
payable in an amount reduced to compensate the Company for any loss, cost,
damage or expense suffered or incurred by the Company as a result in any way of
any such action, misstatement or nondisclosure.

Section 8.9 Gender, Singular and Plural.

     All pronouns and any variations thereof shall be deemed to refer to the
masculine, feminine, or neuter, as the identity of the person or persons may
require. As the context may require, the singular may be read as the plural and
the plural as the singular.

                                                                              23
<PAGE>

Section 8.10 Law Governing.

     This Plan shall be construed, regulated and administered under the laws of
the State of Texas, except to the extent that such laws are preempted by ERISA.

Section 8.11 Notice.

     Any notice or filing required or permitted to be given to the
Administrative Committee under the Plan shall be sufficient if in writing and
hand delivered, or sent by registered or certified mail, to the principal office
of the Company, directed to the attention of the Secretary of the Administrative
Committee. Such notice shall be deemed given as to the date of delivery or, if
delivery is made by mail, as of the date shown on the postmark on the receipt
for registration or certification.

Section 8.12 Successors and Assigns.

     This Plan shall be binding upon the Company and its successors and assigns.

Section 8.13 Provisions for Incapacity.

     If the Administrative Committee deems any person entitled to receive any
payment under the provisions of this Plan incapable of receiving or disbursing
the same by reason of minority, illness or infirmity, mental incompetency, or
incapacity of any kind, the Administrative Committee may, in its sole
discretion, take any one or more of the following actions: it may apply such
payment directly for the comfort, support and maintenance of such person; it may
reimburse any person for any such support theretofore supplied to the person
entitled to receive any such payment; or it may pay such payment to any other
person selected by the Administrative Committee to disburse such payment for the
comfort, support and maintenance of the person entitled thereto, including,
without limitations, to any relative who has undertaken, wholly or partially,
the expense of such person's comfort, care and maintenance, or any institution
in whose care or custody the person entitled to the payment may be. The
Administrative Committee may, in its sole discretion, deposit any payment due to
a minor to the minor's credit in any savings or commercial bank of the
Administrative Committee's choice.

                                                                              24