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                                                                    EXHIBIT 10.8


                            VASTAR RESOURCES, INC.
                              SECOND AMENDMENT TO
                            EXECUTIVE MEDICAL PLAN


     Pursuant to the power of amendment reserved therein, Vastar Resources, Inc.
Executive Medical Plan (the "Plan") is hereby amended effective May 24, 2000, as
follows:

     1.  Paragraph 5 is amended in its entirety and shall now read as follows:

          5.   Retiree Medical Coverage.

               A Retiree (as hereafter defined) may continue participation in
          the Plan.  The term "Retiree" shall mean any Participant who was
          participating in the Plan and who while participating in the Plan:

          (a) Terminated employment and, at such time, was entitled to an
          immediate retirement allowance from a qualified retirement plan of the
          Company; or

          (b) Terminated employment after attainment of age 53 years plus six
          months and ten or more years of Membership Service, as defined in the
          Vastar Resources, Inc. Retirement Plan and is eligible for an
          allowance under the Vastar Resources, Inc. Special Termination
          Allowance Plan.  A Participant described in this subparagraph (b)
          shall become a Retiree upon the date the Participant becomes eligible
          to receive an immediate monthly retirement allowance from a qualified
          retirement plan of the Company; or

          (c) Terminated employment in accordance with the terms and conditions
          of a written agreement between the Company and the Employee, which
          grants the Employee Retiree status.  The applicable provisions of such
          written agreement are incorporated by reference as a provision of the
          Plan; or

          (d) Has a termination of employment as described in Paragraph 2(b)(i)
          of the Plan during a Benefit Trigger Window and the Participant, as of
          the date of the Participant's termination of employment, (A) has
          attained the age of 48 years plus six months or more and (B) as of the
          date of the Participant's termination of employment, has five or more
          years of Membership Service, as defined under the Vastar Resources,
          Inc. Retirement Plan and is eligible for an allowance under the Vastar
          Resources, Inc. Special Termination Allowance Plan.  A Participant
          described in this subparagraph (d) shall become a Retiree on the
          earlier of the 19th month  after such Participant's termination of
          employment or the date the Participant becomes eligible to receive an
          immediate monthly retirement allowance under the Vastar Resources,
          Inc. Retirement Plan.
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     Executed this 6th day of July, 2000.


                              VASTAR RESOURCES, INC.


                                   /s/  JEFFREY M. BENDER
ATTEST:                       By: ----------------------------------
                                    Jeffrey M. Bender
                                    Vice President, Human Resources
     /s/  ANTHONY S. NOONAN
By: --------------------------------
          Anthony S. Noonan
Name:_______________________________
          General Tax Officer
Title:________________________________


Approved as to Form:

WACHOVIA BANK N.A.

     /s/  PETER D. QUINN
By: --------------------------------
          Peter D. Quinn
Name:_______________________________
          Senior Vice President
Title:________________________________

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