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                                                                   EXHIBIT 10.49
                                AMENDMENT NO. 3
                                        
                                      TO
              VASTAR RESOURCES, INC. CAPITAL ACCUMULATION PLAN II
                          __________________________



Pursuant to the resolutions adopted by Board of Directors on October 15, 1997,
the Vastar Resources, Inc. Capital Accumulation Plan II (the "Plan") is hereby
amended effective as of November 1, 1997:


1.   Paragraph 10.1 of the Plan is amended to read as follows:

     "10.1  Amendment of Plan
          (a)  Except as provided in Subparagraph 10.1(b), the Plan may be
               amended by the Board of Directors of Vastar Resources, Inc.

          (b)  A committee consisting of the Vice President, Human Resources,
               the Vice President and Controller, the Vice President and General
               Counsel, and the General Tax Officer of Vastar Resources, Inc.
               may amend the Plan under the following circumstances:

               (i)   Legally required changes;

               (ii)  Improvement of administrative efficiency;

               (iii) Implementation of contractual commitments made by the
                     Company regarding matters relating to acquisitions,
                     divestitures, joint ventures or mergers and any matter
                     negotiated pursuant to a collective bargaining agreement;

               (iv)  Implementation of any transfer of assets, merger or spin-
                     off of plan assets among plans within the Company; or

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               (v)   Implementation of participation in the Plan by Subsidiaries
                     or Affiliates of the Company.


          (c)  No amendment shall reduce the account of any Member as of the
               date of such amendment."



2.    A new Section 15 is added to the Plan to read as follows:

  
                                  "Section 15

      SPECIAL PROVISIONS APPLICABLE TO EMPLOYEES OF THE COMPANY SECONDED 
                      TO SOUTHERN ENERGY MARKETING, L.P.


15.1  Pursuant to an agreement dated as of September 1, 1997, the ("Agreement")
      between the Company and Southern Company Energy Marketing L.P. ("SCEM"),
      certain employees of the Company were seconded to SCEM and its affiliates,
      and as of January 1, 1998, will become SCEM employees in connection with
      the occurrence of the Second Closing (as such term is defined in the
      Formation Agreement between the Company and SEI Holdings, Inc., dated
      August 8, 1997). Such employees are hereinafter referred to as
      "Transferees".

15.2  The rights and benefits under the Plan of Transferees shall be governed by
      the Plan except as provided in this Section 15.

15.3  Effective December 31, 1997, Atlantic Richfield Company Common Stock,
      Dividends Paid-Out, shall be replaced with Atlantic Richfield Company
      Common Stock, Dividends Reinvested.

15.4  As soon as administratively practicable following termination of
      employment with the Company and commencement of employment with SCEM, each
      Transferee's Account shall be transferred to the SCEM Employees Savings
      Plan.  The transfer shall consist of cash and shares of Vastar Resources,
      Inc. and to the extend 

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      applicable, Atlantic Richfield Company Common Stock held in the
      Transferee's Account immediately prior to the transfer.

15.5  To effectuate the transfer of assets and liabilities as contemplated by
      this Section 15, the Administrator may suspend the purchase and sales of
      investment alternatives as necessary in the Administrator's sole
      discretion."



Executed this 30th day of December, 1997.


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

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