EXHIBIT 10.8

                            VASTAR RESOURCES, INC.
                              FIRST AMENDMENT TO
                       AMENDED AND RESTATED SUPPLEMENTARY
                           EXECUTIVE RETIREMENT PLAN

          Pursuant to the power of amendment reserved therein, Vastar Resources,
Inc. Amended and Restated Supplementary Executive Retirement Plan, which was
effective March 24, 1999 (the "Plan") is hereby amended as follows:

          1.    Section 1.3 is amended:

          (a)   to delete subsection (f) "ARCO Acquisition"; subsection (g)
                "ARCO Takeover"; and subsection (aa) "Secondary Change of
                Control"
          (b)   to renumber subsections (h) through (k) as (f) through (i);
          (c)   to renumber subsections (l) through (o) as (k) through (n);
          (d)   to renumber subsection (u) as (v);
          (e)   to renumber subsections (v) through (z) as (x) through (bb);
          (f)   to renumber subsection (bb) and (cc) as (cc) and (dd); and
          (e)   to renumber subsections (dd) and (ee) as (ff) and (gg),

          When amending sections or subsections currently set forth in the Plan,
the section or subsection references below refer to the sections and subsections
as they existed prior to the renumbering as provided for above.  Moreover, all
current references in the Plan to other sections and subsections of the Plan
shall be deemed to refer to the applicable section or subsection as renumbered
herein.

          2.    Section 1.3 is amended to add new subsections (j), (o), (u), (w)
and (ee) to read as follows:

          "(j)  "Benefit Trigger Window" means the 24-month period commencing on
the date immediately following the Effective Time and means each 24-month period
commencing on the date that a Subsequent Change of Control occurs.

           (o)  "Effective Time" " shall be ascribed the meaning set forth for
such term on Annex A attached hereto.

           (u)  "Merger" shall be ascribed the meaning set forth for such term
on Annex A attached hereto.

           (w)  "Parent Company" shall be ascribed the meaning set forth for
such term on Annex A attached hereto.

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          (ee)  "Subsequent Change of Control" shall be ascribed the meaning set
forth for such term on Annex A attached hereto."

          3.    Section 1.3 is amended to delete the last sentence of subsection
(b).

          4.    Section 2.2 is amended to delete subsection (d) effective as of
the Effective Time (as defined in Annex A to the Plan as amended hereby).

          5.    Section 5.3 will be amended to delete Sections 5.3(a), (b) and
(c) and replace them with the following:

          (a)   GENERAL.  Except as provided in Section 5.3(d) below, the
Administrator shall cause an amount equal to a Lump Sum payment for each
Participant (which amount shall include, but not be limited to, all amounts due
to the Participant under this Plan, if any, as a result of his or her
eligibility for the Retirement Allowance as described in Paragraph 30.4 of the
Vastar Resources, Inc. Retirement Plan) to be transferred from the Plan to the
Participant's account in the Vastar Resources, Inc. Executive Deferral Plan, in
the following three circumstances:

               (i)   the Participant has a "Termination of Employment" during a
          Benefit Trigger Window; or

               (ii)  the Benefit Trigger Window following a Subsequent Change of
          Control expires.

          No calculation of a Lump Sum payment or transfer to the Vastar
Resources, Inc. Executive Deferral Plan shall be made prior to January 1, 2000.
After such transfer, the benefits payable under this Plan shall be governed by
the terms of the Vastar Resources, Inc. Executive Deferral Plan, as amended from
time to time.

          (b)   DEFINITION OF TERMINATION OF EMPLOYMENT.  For the purposes of
subsection (a) above, the term "Termination of Employment" shall mean:

                (i)  a termination of employment during a Benefit Trigger Window
     by the Surviving Entity, other than for Cause, or

                (ii) the Employee's voluntary termination within a Benefit
     Trigger Window as a result of the Surviving Entity's implementation of:

                     (A)  a ten percent or more reduction of such Employee's
                Qualifying Pay from the Qualifying Pay determined as of the date

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                immediately prior to the date of the Change of Control, or a ten
                percent or more reduction (based on dollar value) in the
                Employee's aggregate Qualifying Pay plus Target Award ("Total
                Pay") from the Employee's Total Pay determined as of the date
                immediately prior to the date of the Change of Control;

                     (B)  a required relocation of the Employee's principal
               place of work to a location which would satisfy the conditions
               specified in (S) 217(c)(1) of the Internal Revenue Code of 1986,
               as amended (the "Code"), for a deduction by such Employee of
               moving expenses under (S) 217 of the Code; or

                     (C)  with respect to Tier 1 and 2 Employees of the Company,
               a demotion to a lesser job.

               (iii) No Employee shall be deemed to have a termination of
          employment solely due to a transfer of employment directly between the
          Company, a Surviving Entity or any of their affiliates.

          (c)  DEFINITION OF CAUSE, QUALIFYING PAY, SURVIVING ENTITY AND TARGET
AWARD. For purposes of this subsection (b) above, the following definitions
shall apply:

               (i)     "Cause" shall mean (i) the conviction of the Employee for
          any felony involving dishonesty, fraud or breach of trust or (ii) the
          willful engagement by the Employee in gross misconduct in the
          performance of his or her duties that materially injures the Surviving
          Entity.

               (ii)    "Qualifying Pay" means the Employee's annualized rate of
          regular wages or salary, excluding all extra pay such as overtime,
          premiums, bonuses, living or other allowances, determined as of the
          relevant date.

               (iii)   "Surviving Entity" means the Company, or any successor
     (whether direct or indirect, by purchase, merger, consolidation or
     otherwise) to all or substantially all of the business and/or assets of the
     Company after a Change of Control, and its affiliates.

               (iv)    "Target Award" means the annual target performance bonus
     award applicable to the Employee for the relevant period."

     (d) MISCELLANEOUS.  Notwithstanding subsection (a) above:


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          (i)    If a Participant does not have an account in the Vastar
Resources, Inc. Executive Deferral Plan, the Lump Sum payment applicable to the
Participant's benefit under this Plan shall be payable in one of the following
two methods (which shall be selected by the Company at its discretion): (x) as
soon as practicable after the occurrence of the applicable event described in
Section 5.3(a)(i) or (ii) above, or (y) in up to three installments (not
necessarily equal) over a period not to exceed two calendar years beginning on
the date of the occurrence of the applicable event described in Section
5.3(a)(i) or (ii) above. Such payment or payments, when completed shall be in
complete satisfaction of the Participant's accrued rights hereunder.

          (ii)   With respect to (x) the remaining annuity payments to be
received by any Participant or Beneficiary pursuant to this Plan whose annuity
payments have commenced as of the date of any of the events described in
subsection (a) above and (y) the benefit payable to any Participant who
terminated his or her employment prior to any of the events described in Section
5.3(a) (i) or (ii) above (or a Beneficiary who became entitled to a benefit
under this Plan as a result of the death of a Participant occurring prior to any
of the events described in Section 5.3(a) (i) or (ii) above) which has not
commenced as of the date of any of the events described in subsection Section
5.3 (a) (i) or (ii) above, the benefits payable to such persons shall continue
as provided for in this Plan.

          6.     Article VI is amended to add a new Section 6.7 which shall read
as follows:

          "6.7.  Authorized Officers

          Both the Chief Financial Officer and the Vice President, Human
Resources of the Company whose duties with respect to this Plan are provided
herein, will be those persons who have been employed in such positions by the
Company since April 1, 1999.  Any action required to be taken under this Plan by
the Chief Financial Officer and the Vice President, Human Resources of the
Company may be taken by either individual if the other position is vacant.  If
the positions of Chief Financial Officer and Vice President, Human Resources of
the Company are both vacant, actions required to be taken under the Plan by such
officers may only be taken by one of the officers of the Company set forth below
(in the order stated) who was in such position on April 1, 1999:

          (a)  Controller
          (b)  General Counsel
          (c) Senior Vice President of Production
          (d) Senior Vice President of Exploration
          (e) Vice President of Business Development.


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          If none of such persons is in such position, the Special Plan
Administrator shall take actions required to be taken under the Plan."

          7.  Annex A is amended, with respect to the definition of "Change of
Control" and the definition of "Outside Director", to replace the terms
"Atlantic Richfield Company" and "ARCO" with the term "Parent Company".  This
amendment shall be construed consistently with the intent that the Merger, if it
occurs, is a Change of Control.

          8.  Annex A, with respect to the definition of "Change of Control," is
amended, effective immediately after the Effective Time, to add "; or" at the
end of Paragraph (6) and to add new Paragraph (7) which shall read as follows:

          "(7)  A Subsequent Change of Control."

          9.  Annex A is amended to add the following definitions:

          ""Effective Time" means, with respect to the Merger, such time as the
Certificate of Merger is duly filed with the Secretary of State of the State of
Delaware or at such later time as is specified in the Certificate of Merger in
accordance with the Delaware General Corporation Law.

          "Merger" shall mean the merger between Atlantic Richfield Company and
Prairie Holdings, Inc., a subsidiary of BP Amoco p.l.c.

          "Parent Company" shall mean, until the Effective Time of the Merger,
Atlantic Richfield Company and, after Effective Time of the Merger, BP Amoco
p.l.c. or any of its subsidiaries or affiliates and any of their respective
successors.

          "Subsequent Change of Control" shall mean each Change of Control which
occurs after the consummation of a transaction constituting a Change of
Control.""

          10. The Plan is amended to add new Article X which shall read as
 follows:

                                  "ARTICLE X
                       SPECIAL PROVISIONS APPLICABLE TO
                               CERTAIN EMPLOYEES

     1.1  Eligibility

          A Participant in Tier 1 and 2 is eligible for the benefit set forth in
this Article X  in the event he or she voluntarily terminates his or her
employment during a

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Benefit Trigger Window after being demoted, or advised of an
impending demotion to, a lesser job.

     2.1  Rights and Benefits

     A Participant described in Section 1.1 of this Article X shall be entitled,
on the date of his or her Termination of Employment, to a benefit equal to the
Retirement Allowance as described in Paragraph 30.4 of the Vastar Resources,
Inc. Retirement Plan (the "5+5 Benefit").  The 5+5 Benefit shall be calculated
as if it were to be paid from the Vastar Resources, Inc. Retirement Plan but
shall be paid exclusively by this Plan in accordance with the applicable terms
and conditions of this Plan and shall be transferred (but not before December
31, 1999) to the Vastar Resources, Inc. Executive Deferral Plan.  When
calculating benefits under Article II and III of this Plan, a Participant
entitled to the benefit described in Section 1.1 of this Article X shall be
credited with the 5 years of service and 5 years of age as described in Article
30 of the Vastar Resources, Inc. Retirement Plan and be deemed to have been
entitled to, and to have received from the Vastar Resources, Inc. Retirement
Plan, such portion of his or her 5+5 benefit which could have been paid under
the Vastar Resources, Inc. Retirement Plan had the Participant been eligible
thereunder.

     11.  The Plan is amended to replace (except in Section 6.7) the term
"General Counsel" with the term "Vice President, Human Resources."

     12.  Section 9.1 is amended to delete the second sentence and replace it
with the following:

     "Notwithstanding the above, upon an Anticipatory Change Termination (as
defined in Section 1.3(b)), this Plan may again be terminated, subject to
Section 9.3 from time to time by the Board of Directors of Vastar or its
designee."

     13.  Section 9.2 is amended to delete the second sentence and replace it
with the following:

     "Notwithstanding the above, upon an Anticipatory Change Termination, this
Plan may again be amended, subject to Section 9.3 from time to time by the Board
of Directors of Vastar or its designee."

     14.  Section 9.4 is amended to delete the last sentence.

     15.  All amendments shall be effective as of July 21, 1999 unless otherwise
noted.

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     Executed as of the 12th day of August, 1999.


     ATTEST:                                VASTAR RESOURCES, INC.


     By:   /s/ Jonathan D. Edelfelt         By: /s/ Jeffrey M. Bender
          _________________________         __________________________________
          Jonathan D. Edelfelt                  Jeffrey M. Bender
          Associate Secretary                   Vice President, Human Resources



APPROVED as to form this 24th day
of August, 1999

WACHOVIA BANK, N.A.,


By:    /s/ Peter D. Quinn
       --------------------------------
Name:  Peter D. Quinn
       --------------------------------
Title: Senior Vice President
       --------------------------------

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