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                                                                   EXHIBIT 10.13


                    UNOCAL NONQUALIFIED RETIREMENT PLAN "B"
                          (Amended December 5, 2000)

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 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.

Article I - Eligibility

The Employee, or in the proper case, the Spouse of an Employee, shall be
eligible if each of the following provisions are satisfied:

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

B.   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 as a result of a Change in Control Event is entitled to
     a vested right to his or her Accrued Benefit under the Unocal Retirement
     Plan;

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

D.   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 (or Spouse's, if applicable) 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
     (or Spouse, if applicable) 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
     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

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     "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
     the Installment Payment Form shall commence and be paid subject to Article
     III.D.  Benefits under this Plan shall, in addition to any limits 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

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     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 same terms,
     conditions and actuarial adjustments as are 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 cash installments. Such form of payment shall be known as the
     "Installment Payment Form." 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.  Any payment election
     made with respect to the Unocal Supplemental Retirement Plan For Key
     Management Personnel made prior to December 5, 2000 shall continue to apply
     to this Plan until such election is changed in accordance with the
     procedures herein.

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 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, 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, or may change such election after retirement and before
     commencement of payment of benefits, subject to a 10% reduction of his or
     her benefit which will be forfeited to the Company or Employer.

H.   After commencement of payment of benefits, an Employee (or beneficiary who
     is receiving payments) 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 payments under
     the Installment Payment Form, shall be equal to the difference between 1.
     and 2. below, determined as of the commencement date of benefit payments,

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     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.

     When an Employee was receiving payments under the Installment Payment Form,
     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.

     When a beneficiary of a deceased participant elects to receive a single sum
     cash payment, the amount of the single sum cash payment shall be calculated
     in a similar manner.

     A single sum cash payment shall be valued using the interest rate used by
     the Unocal Retirement Plan to determine a Lump Sum Cash Settlement for the
     month in which 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 (or the Employee's beneficiary if the
     Employee is deceased).

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.

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M.   The Spouse (or other beneficiary) of an Employee shall be entitled to
     receive benefits in accordance with the Employee's election of form of
     benefit payment under this Plan and, in the event of the Employee's death
     before his or her Retirement Date, the eligibility of such Spouse (or other
     beneficiary) to receive the benefit under the Unocal Retirement Plan which
     is being supplemented by this Plan.

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 ten 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 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 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.

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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 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.

Article V - Definitions

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

B.   "Code" - The Internal Revenue Code of 1986 as amended from time to time.

C.   "Company" - Unocal Corporation.

D.   "Effective Date" - This Plan shall apply to Employees whose separation from
     service date is on or after January 1, 1998. The Unocal Supplemental
     Retirement Plan For Key Management Personnel, as in effect immediately
     prior

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     to January 1, 1998, shall continue to apply to Employees who separated from
     service prior to January 1, 1998.

E.   "Employee" - A person who is in the employment of an Employer on or after
     the effective date of this Plan.

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

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

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

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