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                                                                   EXHIBIT 10.16

                     UNOCAL NONQUALIFIED RETIREMENT PLAN "B"
                      (AS AMENDED THROUGH JANUARY 1, 2002)

This Unocal Nonqualified Retirement Plan "B" (the "Plan") is an amendment and
restatement of the Unocal Supplemental Retirement Plan For Key Management
Personnel. The Plan has been and is maintained by the Company primarily for the
purpose of providing deferred compensation for a select group of management or
highly compensated employees and only for the purpose of providing retirement
benefits for such employees in excess of the limitations imposed by the Internal
Revenue Service under Section 401(a)(17) of the Code.

The provisions of the Supplemental Retirement Plan for Key Management Personnel
as in effect prior to January 1, 1998 shall continue to apply to determine the
eligibility of and benefits payable to Employees who separated from service
prior to January 1, 1998. The terms of the Plan in effect as of the date
benefits commence shall apply for purposes of determining the form and time of
payment of benefits due under the Plan.

ARTICLE I - ELIGIBILITY

The Employee shall be eligible if each of the following provisions is satisfied:

A.     The Employee is a Member of the Unocal Retirement Plan;

B.     The Employee's salary grade classification with an Employer is M04 or
       above, with respect to eligibility for additional benefits on or after
       January 1, 2001;

C.     At the time of the Employee's separation from service with an Employer,
       the Employee had at least five years of Benefit Service under the Unocal
       Retirement Plan or the Employee is entitled to a vested right to his or
       her Accrued Benefit under the Unocal Retirement Plan as a result of a
       Change of Control Event;

D.     The Employee separates from service with an Employer on or after January
       1, 1998; and

E.     The Employee's "Final Average Monthly Pay" under the Unocal Retirement
       Plan is less than it would have been in the absence of the requirements
       of Section 401(a)(17) of the Code.

ARTICLE II - BENEFIT

A.     The amount of the Employee's monthly benefit shall be equal to the
       excess, if any, of: (1) the monthly benefit which would have been payable
       under the Unocal Retirement Plan to the Employee were it not for the
       limitations imposed by Sections 415 and 401(a)(17) of the Code over (2)
       the sum of (a) the actual

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       monthly benefit payable under the Unocal Retirement Plan and (b) the
       actual monthly benefit payable under the Unocal Nonqualified Retirement
       Plan "A."

B.     In the event that: (1) the monthly benefit computed under Article II.A.1.
       of the Unocal Nonqualified Retirement Plan "C" (determined without regard
       to the Employee's eligibility to participate in such plan) minus (2) the
       sum of (a) the actual monthly benefit payable under the Unocal Retirement
       Plan and (b) the actual monthly benefit payable under the Unocal
       Nonqualified Retirement Plan "A," is less than the benefit calculated
       under Article II.A. of this Plan, the monthly benefit payable under this
       Plan shall be reduced to such lower amount.

C.     Notwithstanding any provision in this Plan, in the event that (1) it
       shall be determined that any benefit or payment under the Plan is a
       "parachute payment" (within the meaning of Section 280G of the Code)
       which is subject to the excise tax imposed by Section 4999 of the Code
       ("Excise Tax"), (2) the Employee is not entitled (pursuant to an
       employment or other agreement) to receive a "gross up" payment to provide
       the Employee with additional compensation to offset the impact of the
       Excise Tax (a "Gross Up Arrangement"), and (3) the Employee would receive
       a greater net after-tax benefit if such Employee's aggregate benefits and
       payments from the Company and its affiliates, whether under the Plan or
       otherwise, were reduced to a level which does not exceed the greatest
       amount that could be paid to the Employee without giving rise to Excise
       Tax (the "Reduced Amount"), then the Employee's benefits or payments
       under the Plan shall be reduced as determined by the Company so the
       benefits or payments under the Plan when aggregated with all benefits and
       payments from the Company and its affiliates do not exceed the Reduced
       Amount. The Employee's net after-tax benefit shall be determined after
       application of the Excise Tax, all federal, state and local income taxes
       and payroll or other taxes, and by including all benefits and payments
       from the Company and its affiliates which are treated as "parachute
       payments" and included in determining liability for the Excise Tax. The
       determination of the applicability of the Excise Tax and the Reduced
       Amount shall be made by the Company in good faith, provided that with
       respect to an Employee who is subject to Gross Up Arrangement or other
       contract or agreement that provides procedures for determining the
       existence of an Excise Tax, the procedures in such Gross Up Arrangement,
       contract or agreement shall apply. If the benefits or payments under the
       Plan are to be reduced to the Reduced Amount and the Employee receives
       other benefits or payments treated as "parachute payments" and included
       in determining liability for the Excise Tax, the Company may allocate
       such portion of the reduction amount to the benefits and payments under
       the Plan as it deems appropriate.

ARTICLE III - FORM AND TIME OF PAYMENT

A.     Benefits under this Plan shall commence at the same time as benefits
       under the Unocal Retirement Plan, except that benefits paid under this
       Plan in installments shall commence and be paid subject to Article III.D.
       Benefits under this Plan

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       shall, in addition to any Iimits imposed herein, be subject to the
       provisions of the Unocal Retirement Plan, except as specifically provided
       otherwise by this Plan.

B.     An eligible Employee may elect to receive payments under this Plan under
       any of the forms of payment available under the Unocal Retirement Plan,
       except the Five Years Certain Life Annuity Form and the Ten Years Certain
       Life Annuity Form, with respect to his or her benefit under this Plan.
       For purposes of this Plan, the Lump Sum Cash Settlement Form is referred
       to as a single sum cash payment.

C.     The forms of payment under this Plan shall be subject to the terms,
       conditions and actuarial adjustments applicable to such forms under the
       Unocal Retirement Plan.

D.     Notwithstanding the foregoing, an Employee may elect, subject to such
       dates, terms, and conditions as the Company deems appropriate, to receive
       the single sum cash payment amount, as determined above, payable in up to
       ten annual installments. No interest shall accrue or be credited to such
       payments or amounts.

E.     An eligible Employee may make a timely election of the form of payment of
       his or her benefits under this Plan, and may change such election without
       penalty by making a subsequent timely election, at any time not later
       than one year prior to the Employee's retirement date.

F.     If an Employee does not make a timely election of the form of payment of
       benefits, then benefits under this Plan will be paid as a single sum cash
       payment for benefits commenced on or after September 1, 2001 or a Single
       Life Annuity, if the Employee is not married, or as a 100% Joint and
       Survivor Life Annuity for the Employee and his or her Spouse, if the
       Employee is married, for benefits commenced before September 1, 2001,
       unless the Employee makes an election which is subject to a reduction of
       benefits under Article III.G. or III.H. below.

G.     An eligible Employee may change his or her election of the form of
       payment of benefits under this Plan within one year before retirement,
       subject to a 6% reduction of his or her benefit which will be forfeited
       to the Company or Employer. Notwithstanding the preceding sentence, the
       6% reduction penalty shall not apply with respect to the form of payment
       elected during a special election period designated by the Administrator
       as attributable to a Plan amendment.

H.     After retirement, an Employee may elect to receive his or her remaining
       benefits under this Plan in a single sum cash payment, subject to a 10%
       reduction of the single sum cash payment, which will be forfeited to the
       Company or Employer.

I.     The single sum cash payment to an Employee under Article III.H. (prior to
       the 10% reduction), except when the Employee was receiving installment
       payments,

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       shall be equal to the difference between 1. and 2. below, determined as
       of the commencement date of benefit payments, accumulated to the date of
       the single sum cash payment using the interest rate specified below.

       1.     The single sum value of the benefits payable to the Employee as a
              Single Life Annuity under this Plan determined as of the
              commencement date of benefit payments.

       2.     The single sum value of the benefits previously paid to the
              Employee under this Plan (based on the actual form of payments,
              unless the Employee was receiving payments under a Joint and
              Survivor Life Annuity form and the joint annuitant has died, in
              which case the value of benefits previously paid shall be
              considered to be the benefits which would have been paid to the
              Employee as a Single Life Annuity) discounted to the commencement
              date of benefit payments.

       If an Employee is receiving installment payments, the single sum cash
       payment to the Employee under Article III.H. (prior to the 10% reduction)
       shall be equal to the remaining unpaid installment payments, without
       interest.

       A single sum cash payment shall be valued using the interest rate used by
       the Unocal Retirement PIan to determine a Lump Sum Cash Settlement
       payable on the first of the month following the date the election under
       Section III.H. above is received by the Company.

J.     Within two years after a Change of Control, the reduction of benefits
       under Article III.G. and III.H. shall be 5%, in lieu of the 6% or 10%
       reduction which otherwise would apply. For this purpose a "Change of
       Control" shall have the same meaning as a "Change in Control Event" as
       defined in the Unocal Long-Term Incentive Plan of 1998.

K.     The Unocal Retirement Plan Committee, in its discretion, may waive
       reductions in benefits for changes in elections of form of payment of
       benefits or elections to receive single sum cash payments which are due
       to a financial hardship of the Employee.

L.     If any provision of this Plan causes Plan benefits to be includible for
       federal income tax purposes in the gross income of an Employee (or
       beneficiary) prior to actual payment of such Plan benefits to the
       Employee (or beneficiary), the Company shall pay such Plan benefits to
       the Employee (or beneficiary) upon a final determination to such effect,
       notwithstanding any other provision of this Plan to the contrary.

M.     The Spouse (or other beneficiary) of an Employee may be entitled to
       benefits in the event of the death of the Employee.

       1.     If the Employee dies prior to commencement of payment of benefits,
              a benefit shall be payable only to the Employee's Spouse and only
              if the Spouse has

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              been married to the Employee for a period of at least one year on
              the date of the Employee's death. The amount of the benefit
              payable to the Employee's eligible Spouse shall equal the amount
              that would be paid from the Unocal Retirement Plan under the
              Spouse's Annuity Benefit, the Special Spouse's Benefit, the
              Spouse's Benefit, or the Spouse's Employee-Equivalent Benefit,
              provided that the eligibility requirements under the Unocal
              Retirement Plan have been met for the elected benefit, with the
              calculation based on the Member's benefit under Article II.A and
              Article II.B of this Plan. Benefits under this Plan will commence
              at the same time as benefits under the Unocal Retirement Plan. If
              a Spouse elects to receive the Spouse's Employee-Equivalent
              Benefit, the Spouse may elect, subject to such dates, terms, and
              conditions as the Company deems appropriate, to receive such
              benefit payable in up to ten annual cash installments. No interest
              shall accrue or be credited to such payments. No other benefit
              shall be payable to any other person or entity in the event that a
              benefit is paid under this Article III.M.1.

       2.     If the Employee dies after commencement of payment of benefits,
              the amount, timing and form of the benefit payments under this
              Plan shall be in accordance with the Employee's election of form
              of payment under this Plan.

              a.     If the Employee elected installment payments or the Ten
                     Equal Annual Installments, the Spouse (or beneficiary) will
                     receive one payment in an amount equal to the remaining
                     payments.

              b.     If the Employee elected a Joint and Survivor Life Annuity,
                     payments will continue for the life of the Spouse (with
                     appropriate reduction based on the Employee's election).

              c.     If the Employee elected the Single Life Annuity, no benefit
                     will be paid from this Plan to the Spouse (or beneficiary).

              No other benefit shall be payable to any other Beneficiary or
              entity in the event that a benefit is paid under this Article
              III.M.2.

ARTICLE IV - ADMINISTRATION AND TERMINATION

A.     Union Oil Company of California shall administer the Plan. Such
       responsibilities shall be carried out through its corporate officers and
       employees acting in their capacities as officers and employees and not as
       fiduciaries.

B.     The Board of Directors may terminate or amend any or all of the
       provisions of or add provisions to this Plan at any time. However, no
       termination or amendment of this Plan shall reduce or adversely affect
       (i) the benefit then being paid under this Plan, or (ii) the benefit
       (including optional forms of benefit) that an Employee would be eligible
       to receive under this Plan in the event that, within five years of the
       effective date of the termination or amendment of this Plan, he or she
       retires with an immediate retirement benefit under the Unocal Retirement
       Plan or dies. After a Change of Control, the Plan may not be amended to
       eliminate or modify

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       the right of an Employee (or beneficiary) to receive a single sum cash
       payment of his or her benefits pursuant to Article III.

C.     No Employee, beneficiary or joint annuitant may assign, transfer,
       hypothecate, encumber, commute or anticipate his or her interest in any
       benefits under this Plan. Interests and payments under this Plan are to
       be free from voluntary or involuntary assignment, and judicial levy and
       execution to the full extent permissible under applicable law.

D.     Payments under this Plan shall be made from the general funds of the
       Company or an Employer or from a grantor (rabbi) trust established by the
       Company or Union Oil Company of California, unless otherwise provided for
       by the Board of Directors.

E.     The Unocal Retirement Plan Committee shall have sole discretion regarding
       interpretation of this Plan and making factual determinations. Unless
       defined below or otherwise indicated, capitalized or quoted materials
       refer to the meanings and definitions under the Unocal Retirement Plan.
       Any questions that arise as to the rights to and amount of any benefits
       under this Plan or as to the interpretation of any of its provisions
       shall be determined by said Committee.

F.     Nothing in this Plan shall give any person a right to remain in the
       employment of the Employer or affect the right of the Employer to modify
       or terminate the employment of an Employee at any time, with or without
       cause.

G.     Any controversy or claim arising out of or relating to this Plan shall be
       settled by binding arbitration in Los Angeles, California, in accordance
       with the Commercial Arbitration Rules of the American Arbitration
       Association. The parties shall seek to agree upon appointment of the
       arbitrator and the arbitration procedures. If the parties are unable to
       reach such agreement, a single arbitrator who is a retired judge of a
       Federal or California state court shall be appointed pursuant to the AAA
       Commercial Arbitration Rules, and the arbitrator shall determine the
       arbitration procedures. Any award pursuant to such arbitration shall be
       included in a written decision which shall state the legal and factual
       reasons upon which the award was based, including all the elements
       involved in the calculation of any award. Any such award shall be deemed
       final and binding and may be entered and enforced in any state or federal
       court of competent jurisdiction. The arbitrator shall interpret the Plan
       in accordance with the laws of California. The arbitrator shall be
       authorized to award reasonable attorney's fees and other
       arbitration-related costs to a Participant or his or her beneficiary if
       an award is made in favor of the Participant or beneficiary. The award
       shall be limited to Plan benefits at issue, reasonable attorneys' fees
       and arbitration-related costs.

H.     The Plan shall not be terminated by a transfer or sale of assets of the
       Company or by the merger or consolidation of the Company into or with any
       other corporation or other entity. The Plan shall be binding upon and
       inure to the benefit of any successor of the Company provided, however,
       that the Company

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       or its successor may terminate the Plan, in whole or in part, at such
       time as it may determine in its sole discretion. Upon such termination,
       all affected Employees shall become fully vested in the benefits payable
       hereunder and the Company or its successor may choose, in its discretion,
       to accelerate the payment of an Employee's benefits to the actuarial
       present value thereof. For purposes of determining the actuarial present
       value of a benefit, the payment of which is accelerated upon termination
       of the Plan, the actuarial assumptions provided in the Unocal Retirement
       Plan shall apply.

I.     This Plan and the Unocal Nonqualified Retirement Plan "C" collectively
       provide the benefits previously payable under the Unocal Supplemental
       Retirement Plan For Key Management Personnel. Benefits under the Unocal
       Supplemental Retirement Plan For Key Management Personnel which commence
       on or after January 1, 2001 shall be treated as payable under this Plan
       and the Unocal Nonqualified Retirement Plan "C" in such proportions as to
       the Administrator shall reasonably determine in accordance with the
       purposes of the respective plans.

ARTICLE V - DEFINITIONS

A.     "Board of Directors" - The Board of Directors of Unocal Corporation.

B.     "Company" - Unocal Corporation.

C.     "Employee" - A person who is in the employment of an Employer.

D.     "Employer" - Unocal Corporation, Union Oil Company of California and any
       other subsidiary or affiliate of the Company so designated by the Board
       of Directors.

E.     "Law" - The Plan shall be governed by and construed in accordance with
       the laws of the State of California.

F.     "Plan" - Unocal Nonqualified Retirement Plan "B."