FIRST AMENDMENT TO STOCK PURCHASE AGREEMENT

     THIS FIRST AMENDMENT TO STOCK PURCHASE AGREEMENT (this "Amendment") is
dated December 16, 1999, but effective as of October 8, 1999, among Tesoro
Petroleum Corporation, a Delaware corporation ("TPC"), Tesoro Gas Resources
Company, Inc., a Delaware corporation ("TGRC"), EEX Operating LLC, a Delaware
limited liability company ("EEX Operating"), and EEX Corporation, a Texas
corporation ("EEX Corporation"), for the limited purposes set forth herein and
in the Agreement.

     Capitalized terms used and not otherwise defined, or defined as amended, in
this Amendment shall have the meanings given such terms in the Agreement.

                                  WITNESSETH:
                                  -----------

     WHEREAS, TPC, TGRC, EEX Operating and EEX Corporation (for limited
purposes), entered into a Stock Purchase Agreement (the "Agreement") dated
October 8, 1999 providing for the sale by TPC and TGRC to EEX Operating of all
shares of capital stock of Tesoro Exploration and Production Company, a Delaware
corporation ("Exploration") and Tesoro Reserves Company, a Delaware corporation
("Reserves"), together with the partnership interests owned by Reserves and
Exploration in Tesoro E&P Company, L.P., a Delaware limited partnership (the
"E&P Partnership"); and

     WHEREAS, Section 2.9 of the Agreement provides for the Parties to enter
into put and call options for the purchase of the stock of Tesoro Natural Gas
Company, a Delaware corporation ("Natural Gas"), and Tesoro Gathering Company, a
Delaware corporation ("Gathering"), together with the partnership interests (i)
owned by Natural Gas and Gathering in Tesoro Pipeline Company, L.P., a Delaware
limited partnership (the "Pipeline Partnership"), and (ii) owned by Natural Gas
and the Pipeline Partnership in the Starr-Zapata Partnership and the Starr
County Gathering System; and

     WHEREAS, Section 9.12(b) of the Agreement provides for the Parties to
cooperate, at no cost or liability to Buyer, to enable Seller, at Seller's
election, to transfer the Operating Assets (as defined in the Agreement) to
Buyer in a manner enabling the transfer to qualify as a like-kind exchange of
property by Seller within the meaning of Section 1031 of the Code; and

     WHEREAS, in connection with a financing contemplated by Section 9.12(c) of
the Agreement, the Agreement will be amended to provide for the possibility of
(i) two separate buyers, one of which will purchase the Common Stock, and the
other of which will purchase the Membership Interests, and (ii) EEX Operating,
which is executing this Amendment in its capacities as the purchaser of the
Common Stock and the Membership Interests, to transfer its rights and
obligations as the buyer of the Common Stock and/or the Membership Interests to
an Affiliate of EEX Operating; and

     WHEREAS, in order to effect the sale contemplated by Section 2.9, the like-
kind exchange contemplated by Section 9.12 of the Agreement and the separation
of the buyers of the Common Stock and the Membership Interests, the Parties have
agreed to amend the Agreement in accordance with the terms of this Amendment;


     NOW, THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth, the parties hereby agree as follows:

1.   Changes to Article I, Definitions.
     ----------------------------------

     a.  New Defined Terms  The following defined terms shall be added to
         -----------------
     Article I of the Agreement:

     "Amendment" shall mean this First Amendment to Stock Purchase Agreement
     dated December 16, 1999, among Tesoro Petroleum Corporation, Tesoro Gas
     Resources Company, Inc. and EEX Operating LLC, and EEX Corporation, for
     limited purposes.

     "Coastal" shall mean Coastal States Gas Transmission Company, a Delaware
     corporation.

     "E&P Buyer" shall mean the buyer of the Membership Interests, and shall
     initially be EEX Operating LLC, a Delaware limited liability company.

     "E&P Closing Settlement Price" shall mean the E&P Settlement Price
     calculated in accordance with the best information available to the Seller
     prior to Closing, as reflected on the E&P Settlement Statement delivered
     prior to Closing pursuant to Article X and Section 13.2(a).

     "E&P Final Settlement Price" shall mean the E&P Settlement Price calculated
     in accordance with the best information available to the Parties during the
     one hundred twenty (120) day period after Closing, as reflected on the E&P
     Final Statement agreed upon pursuant to Article XIII.

     "E&P Final Statement" shall mean the final accounting statement with
     respect to the Membership Interests to be agreed upon by the Parties no
     later than one hundred twenty (120) days after Closing pursuant to Section
     13.2(b).

     "E&P Partnership" shall mean Tesoro E&P Company, L.P., a Delaware limited
     partnership.

     "E&P Property Package" shall mean the Properties listed on Schedule I.

     "E&P Purchase Price" shall have the meaning given such term in Section
     3.1(a) hereof.

     "E&P Settlement Price" shall have the meaning set forth in Section 3.2.

     "E&P Settlement Statement" shall mean the accounting statement calculating
     the E&P Settlement Price described in Section 13.2(a).

                                       2


     "Exploration and Production Assets" shall mean all property rights and
     interests of the E&P Partnership being sold hereunder in the lands and
     leases described in Exhibit B, as set forth in Section 2.4(a).

     "Exploration LLC" shall mean Tesoro Exploration and Production Company,
     LLC, a Delaware limited liability company.

     "Grande" shall mean Tesoro Grande Company, LLC, a Delaware limited
     liability company.

     "Grande Property Package" shall mean the Properties listed on Schedule II.

     "Grande Qualified Intermediary" shall mean Bank One Exchange Corporation,
     in its capacity as a qualified intermediary to implement a like-kind
     exchange of the Grande Property Package under Section 1031 of the Code.

     "LLC Purchase Agreements" shall have the meaning set forth in Section
     12.2(g) hereof.

     "LLCs" shall mean Grande, Southeast, Exploration LLC and Reserves LLC.

     "Membership Interests" shall mean all issued and outstanding membership
     interests in Exploration LLC, Reserves LLC, Grande and Southeast,
     collectively.

     "Pipeline Buyer" shall mean the buyer of the Common Stock, and shall
     initially be EEX Operating LLC, a Delaware limited liability company.

     "Pipeline Closing Settlement Price" shall mean the Settlement Price
     calculated in accordance with the best information available to the Seller
     prior to Closing, as reflected on the Settlement Statement delivered prior
     to Closing pursuant to Article X and Section 13.2(a).

     "Pipeline Final Settlement Price" shall mean the Pipeline Settlement Price
     calculated in accordance with the best information available to the Parties
     during the one hundred twenty (120) day period after Closing, as reflected
     on the Pipeline Final Statement agreed upon pursuant to Article XIII.

     "Pipeline Final Statement" shall mean the final accounting statement with
     respect to the Common Stock to be agreed upon by the Parties no later than
     one hundred twenty (120) days after Closing pursuant to Section 13.2(b).

     "Pipeline Partnership" shall mean Tesoro Pipeline Company, L.P., a Delaware
     limited partnership.

                                       3


     "Pipeline Properties" shall mean the pipelines and appurtenances, and
     rights-of-ways, easements, servitudes, licenses, permits and other rights
     and interests in the pipelines listed on Exhibit B-1 attached hereto.

     "Pipeline Purchase Price" shall have the meaning given such term in Section
     3.1(a) hereof.

     "Pipeline Settlement Price" shall have the meaning set forth in Section
     3.3.

     "Pipeline Settlement Statement" shall mean the accounting statement
     calculating the Pipeline Settlement Price described in Section 13.2(a).

     "Qualified Intermediary" shall mean both, or either, as applicable, the
     Southeast Qualified Intermediary and the Grande Qualified Intermediary.

     "Reserves LLC" shall mean Tesoro Reserves Company, LLC, a Delaware limited
     liability company.

     "Southeast" shall mean Tesoro Southeast Company, LLC, a Delaware limited
     liability company.

     "Southeast Property Package" shall mean the Properties listed on Schedule
     III.

     "Southeast Qualified Intermediary" shall mean 44 Exchange Services L.L.C.,
     in its capacity as a qualified intermediary to implement a like-kind
     exchange of the Southeast Property Package under Section 1031 of the Code.

     b.  Amended Definitions:    The following defined terms in Article I of the
         --------------------
     Agreement shall be amended to read as follows:

     "Agreement" shall mean this Stock Purchase Agreement, as amended.

     "Allocated Values" shall mean the monetary value allocated to each Property
     or group of Properties, the Pipeline Properties and the Hedging Contracts
     in Exhibit A.

     "Balance Sheets" shall mean the unaudited combined financial balance sheet
     of the Subsidiaries and the Partnership as of June 30, 1999, attached
     hereto as Exhibits C and C-1.

"Buyer" shall mean (i) EEX Operating LLC, a Delaware limited liability company,
if acting as both the E&P Buyer and the Pipeline Buyer or (ii) the E&P Buyer and
the Pipeline Buyer, collectively, if the E&P Buyer and the Pipeline Buyer are
different Persons.

     "Common Stock" shall mean all issued and outstanding shares of common stock
     of Natural Gas and Gathering, collectively; further, during the period
     Exploration and Reserves remain as corporations, prior to their conversion
     to limited liability companies,

                                       4


     then the term "Common Stock" shall also include all issued and outstanding
     shares of common stock of Exploration and Reserves.

     "Consent to Assignment" shall mean an existing contractual or legal right
     of any third party to consent to a Partnership's assignment of an Operating
     Asset or an interest in an Operating Asset to Buyer under such terms as are
     set forth in this Agreement.

     "Operating Assets" shall mean the Exploration and Production Assets, the
     Pipeline Properties and, otherwise, all property rights and interests of
     the Partnership being sold hereunder in the lands and leases described in
     Exhibit B and Exhibit B-1, as set forth in Section 2.4.

     "Partnership" shall mean either or both of the E&P Partnership and the
     Pipeline Partnership, as the context may require.

     "Preferential Right to Purchase" shall mean the right of any third party
     under an existing contract or agreement allowing that third party to
     purchase a Property or either of the Starr Partnership's interest in a
     Pipeline Property whenever Seller proposes to transfer its interests in a
     Partnership under terms such as are set forth in this Agreement.

     "Purchase Price" shall mean the sum of the E&P Purchase Price and the
     Pipeline Purchase Price.

     "Subsidiaries" shall mean Exploration LLC (and Exploration, its predecessor
     corporation), Reserves LLC (and Reserves, its predecessor corporation),
     Grande, Southeast, Natural Gas and Gathering, collectively.

     "Transaction" shall mean the purchase and sale of the Common Stock and the
     Membership Interests pursuant to this Agreement and the related
     transactions contemplated herein.

     c.  The following defined terms in Article I of the Agreement shall be
     deleted in their entirety:

     "Closing Settlement Price"
     "Final Settlement Price"
     "Final Statement"
     "Settlement Price"
     "Settlement Statement"

2.   Changes to Article II, Purchase And Sale.
     -----------------------------------------

     a.  Section 2.1 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

                                       5


     2.1  Sale of Membership Interests and Common Stock.  Subject to the terms
          ---------------------------------------------
     and conditions of this Agreement, (a) Seller agrees to sell and assign to
     E&P Buyer, and E&P Buyer agrees to purchase and pay for, at Closing, all
     the Membership Interests, and (b) Seller agrees to sell and assign to
     Pipeline Buyer, and Pipeline Buyer agrees to purchase and pay for, at
     Closing, all the Common Stock.

     b.   Section 2.2 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

     2.2  Effect of Sale.  The sale of the Membership Interests at Closing shall
          --------------
     transfer to E&P Buyer all of Seller's rights in the LLCs, and the sale of
     the Common Stock at Closing shall transfer to Pipeline Buyer all of
     Seller's rights in Natural Gas and Gathering.  On the Closing Date, the
     Subsidiaries shall hold certain interests, assets and liabilities, as set
     forth in this Article II.  Except as otherwise specifically set forth in
     this Agreement, the transfer of Seller's rights in the Subsidiaries shall
     assign to Buyer all of Seller's beneficial right, title, interest and
     obligations in and to such interests, assets and liabilities held by the
     Subsidiaries.

     c.   Section 2.3 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

     2.3  Partnership.  On the Closing Date, the E&P Partnership and the
          -----------
     Pipeline Partnership shall be owned in the following manner:

          (a) E&P Partnership  Exploration LLC, Grande, Southeast and Reserves
              ---------------
          LLC shall collectively own all rights and interests in the E&P
          Partnership.  Exploration LLC shall be the sole general partner in the
          E&P Partnership, and Grande, Southeast and Reserves LLC shall be the
          sole limited partners in the E&P Partnership.  The partnership rights
          and interests described in this Section 2.3(a) shall pass to E&P Buyer
          as an attribute of the sale of the Membership Interests pursuant to
          this Agreement.

          (b) Pipeline Partnership.  Natural Gas and Gathering shall
              ---------------------
          collectively own all rights and interests in the Pipeline Partnership.
          Natural Gas shall be the sole general partner, owning a one percent
          (1%) partnership interest, and Gathering shall be the sole limited
          partner, owning a ninety-nine percent (99%) partnership interest in
          the Pipeline Partnership.  The partnership rights and interests
          described in this Section 2.3(b) shall pass to Pipeline Buyer as an
          attribute of the sale of the Common Stock pursuant to this Agreement.

          (c) Starr Partnerships.  On the Closing Date, (i) Pipeline Partnership
              ------------------
          shall be the 49% partner and Natural Gas shall be the 1% partner of
          Starr-Zapata Partnership and (ii) Pipeline Partnership shall be the
          69% partner and Natural Gas shall be the 1% partner of the Starr
          County Gathering System.  The partnership rights and interests
          described in this Section 2.3(c) shall pass to Pipeline Buyer as an
          attribute of the sale of the Common Stock pursuant to this Agreement.

                                       6


     d.   The introductory paragraph of Section 2.4 of the Agreement is amended
          and restated in its entirety to read as follows:

          On the Closing Date, the Partnership and the Starr Partnerships shall
          own the Operating Assets, subject to the Permitted Encumbrances, and
          excluding the items set forth on Schedule 2.4 and as otherwise limited
          herein as follows:

e.   The following paragraph (c) is added to Section 2.4 of the Agreement:

          (c)  Pipeline Assets.
               ---------------

               (i)   Rights, title and interests of the Pipeline Partnership and
               the Starr Partnerships in the Pipeline Properties in Starr,
               Edwards, Val Verde and Zapata Counties, Texas, as described in
               Exhibit B-1;

               (ii)  Rights, obligations, title and interests of the Pipeline
               Partnership and the Starr Partnerships in and to permits, orders,
               abstracts of title, leases, deeds, operating agreements,
               participation agreements, and other agreements and instruments
               applicable to the Pipeline Properties;

               (iii) Rights, obligations, title and interests in easements,
               rights of way, licenses and permits and all other rights,
               privileges, benefits and powers conferred upon the owner and
               holder of interests in the Pipeline Properties.

               (iv)  Rights and interests in records and maps, contract files
               and records, accounting files, data and records, all computer
               software and other materials (whether electronically stored or
               otherwise) used or held for use by Seller, the Subsidiaries, the
               Pipeline Partnership or the Starr Partnerships, or any of their
               direct or indirect parents, subsidiaries or other Affiliates
               (other than Coastal), regarding ownership or operation of the
               Pipeline Properties, and other files, documents and records of
               Seller, the Subsidiaries, the Pipeline Partnership or the Starr
               Partnerships, or any of their direct or indirect parents,
               subsidiaries or other Affiliates (other than Coastal), which
               relate to the Pipeline Properties.

     f.  Section 2.9 of the Agreement is hereby deleted in its entirety.

3.   Changes to Article III, Purchase Price and Settlement Price.
     ------------------------------------------------------------

     a.  Section 3.1 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

                                       7


      3.1 Purchase Price.
          --------------

          (a) Purchase Price.  The monetary consideration ("E&P Purchase Price")
              ---------------
          for the sale and conveyance of all the Membership Interests to E&P
          Buyer, effective as of the date of Closing, is E&P Buyer's payment of
          $215,253,969 in cash.  The monetary consideration ("Pipeline Purchase
          Price") for the sale and conveyance of all the Common Stock to
          Pipeline Buyer, effective as of the date of Closing, is Pipeline
          Buyer's payment of $6,746,031 in cash.

          (b)  Allocation of E&P Purchase Price.   The E&P Purchase Price shall
               ---------------------------------
          be allocated among the Grande Property Package, the Southeast Property
          Package and the E&P Property Package as follows:


               (i)  Grande Property Package     --   $115,304,126

               (ii)  Southeast Property Package --   $ 14,426,631

               (iii) E&P Property Package       --   $ 85,523,212

                     Total                      --   $215,253,969

          (c)  The parties agree that the allocation of the E&P Purchase Price
          provided herein, and any inability to allocate the E&P Purchase Price
          as provided herein, shall not affect the total E&P Purchase Price paid
          by E&P Buyer under this Agreement, and the total adjustments to the
          E&P Purchase Price described in this Agreement (including without
          limitation Section 3.2 and Article XIII).

          (d)  None of the E&P Buyer, the Pipeline Buyer, or any Affiliate of
          either Buyer shall be obligated to pay Seller the E&P Purchase Price,
          the Pipeline Purchase Price, or any amounts for any of the Membership
          Interests or the Common Stock, or pursuant to indemnification claims,
          except pursuant to this Agreement.

      b.  Section 3.2 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

          3.2  E&P Settlement Price. Pursuant to the provisions as described
               --------------------
     below, the E&P Purchase Price to be paid by E&P Buyer will be subject to
     certain adjustments made at Closing and within one hundred twenty (120)
     days thereafter, as set forth in Article XIII, to determine the E&P
     Settlement Price amount that will actually be paid by E&P Buyer. The E&P
     Settlement Price will be allocated separately for the E&P Property Package,
     the Grande Property Package and the Southeast Property Package, and shall
     be calculated as follows:

              (a)  Increases.  The E&P Purchase Price shall be increased by the
     following amounts:


            (i)  An amount equal to the expenses attributable to the Membership
                 Interests, the E&P Partnership or the Properties (without
                 duplication) properly accrued in accordance with GAAP and past
                 practice, and as provided for in Section 13.3, attributable to
                 the period from the Effective Time to the end of business on
                 the Closing Date; provided, however, that such expenses shall
                 exclude all (1) depreciation, depletion and amortization, (2)
                 income and franchise taxes, (3) one-half of the amount accrued
                 by the Subsidiaries and the Partnership under incentive
                 compensation arrangements for the Retained Employees, as
                 provided in Section 9.9(c), and (4) severance obligations and
                 other amounts accrued under any employment retention and
                 management stability agreements, as provided in Section 9.9(b);
                 provided, further, however that Seller, the Subsidiaries and
                 the Partnership shall be permitted to accrue no more than
                 $40,000 per month from the close of business on June 30, 1999
                 to the Closing Date for corporate general and administrative
                 expenses;

          (ii)   An amount equal to the capital expenditures relating to the
                 Business attributable to the Membership Interests, the E&P
                 Partnership or the Properties (without duplication), properly
                 accrued in accordance with GAAP and past practice attributable
                 to the period from the Effective Time to the end of business on
                 the Closing Date; and

          (iii)  The amount of change in Working Capital attributable to the
                 Membership Interests, the E&P Partnership or the Properties
                 (without duplication) between the Effective Time and the end of
                 business on the Closing Date, if the amount of change is a
                 positive number.

       (b)  Decreases.  The E&P Purchase Price shall be decreased by the
                 following amounts:

            (i)  An amount equal to the revenues properly accrued in accordance
                 with GAAP and past practice attributable to the Membership
                 Interests, the E&P Partnership or the Properties (without
                 duplication) and attributable to the period from the Effective
                 Time to the end of business on the Closing Date;

          (ii)   An amount equal to any Settlement Price Adjustment, subject to
                 the application of Section 13.1;

          (iii)  The amount of the Allocated Value of any Properties that third
                 parties shall have purchased before the Closing through the
                 exercise of Preferential Rights to Purchase or pursuant to any
                 other sale permitted by Section 9.2(a); and

          (iv)   The amount, stated as a positive number, of any change in
                 Working Capital attributable to the Membership Interests, the
                 E&P Partnership or the Properties (without duplication) between
                 the Effective Time and the end of business on the Closing Date,
                 if and only if, the amount of change is a negative number.


     The E&P Purchase Price as adjusted pursuant to this Section 3.2 is herein
     called the "E&P Settlement Price."

     c.   The following Section 3.3 is hereby added to the Agreement:

             3.3  Pipeline Settlement Price. Pursuant to the provisions as
                  -------------------------
     described below, the Pipeline Purchase Price to be paid by Pipeline Buyer
     will be subject to certain adjustments made at Closing and within one
     hundred twenty (120) days thereafter, as set forth in Article XIII, to
     determine the Pipeline Settlement Price amount that will actually be paid
     by Pipeline Buyer, and shall be calculated as follows:

     (a)  Increases.  The Pipeline Purchase Price shall be increased by the
     following amounts:

          (i)    An amount equal to the expenses attributable to the Common
                 Stock (excluding Reserves and Exploration), the Pipeline
                 Partnership or the Pipeline Properties (without duplication)
                 properly accrued in accordance with GAAP and past practice, and
                 as provided for in Section 13.3, attributable to the period
                 from the Effective Time to the end of business on the Closing
                 Date; provided, however, that such expenses shall exclude all
                 (1) depreciation, depletion and amortization, (2) income and
                 franchise taxes, (3) amounts accrued by the Subsidiaries and
                 the Partnership under incentive compensation arrangements for
                 the Retained Employees, as provided in Section 9.9(c), and (4)
                 severance obligations and other amounts accrued under any
                 employment retention and management stability agreements, as
                 provided in Section 9.9(b); provided, further, however that
                 Seller, the Subsidiaries and the Partnership shall not be
                 permitted to accrue any corporate general and administrative
                 expenses from the close of business on June 30, 1999 to the
                 Closing Date;

          (ii)   An amount equal to the capital expenditures relating to the
                 Business attributable to the Common Stock (excluding Reserves
                 and Exploration), the Pipeline Partnership or the Pipeline
                 Properties (without duplication), properly accrued in
                 accordance with GAAP and past practice attributable to the
                 period from the Effective Time to the end of business on the
                 Closing Date; and

          (iii)  The amount of change in Working Capital attributable to the
                 Common Stock (excluding Reserves and Exploration), the Pipeline
                 Partnership or the Pipeline Properties (without duplication),
                 between the Effective Time and the end of business on the
                 Closing Date, if the amount of change is a positive number.

     (b)  Decreases.  The Pipeline Purchase Price shall be decreased by the
     following amounts:


          (i)    An amount equal to the revenues attributable to the Common
                 Stock (excluding Reserves and Exploration), the Pipeline
                 Partnership or the Pipeline Properties (without duplication)
                 properly accrued in accordance with GAAP and past practice
                 attributable to the period from the Effective Time to the end
                 of business on the Closing Date;

          (ii)   An amount equal to any Settlement Price Adjustment, subject to
                 the application of Section 13.1;

          (iii)  The amount of the Allocated Value of the Pipeline Properties
                 that third parties shall have purchased before the Closing
                 through the exercise of Preferential Rights to Purchase or
                 pursuant to any other sale permitted by Section 9.2(a); and

          (iv)   The amount, stated as a positive number, of any change in
                 Working Capital, attributable to the Common Stock (excluding
                 Reserves and Exploration), the Pipeline Partnership or the
                 Pipeline Properties (without duplication), between the
                 Effective Time and the end of business on the Closing Date, if
                 and only if, the amount of change is a negative number.

     The Pipeline Purchase Price as adjusted pursuant to this Section 3.2 is
     herein called the "Pipeline Settlement Price."

4.   Changes to Article IV, Representations and Warranties.

     a.   Section 4.1 of the Agreement is hereby amended and restated in its
     entirety to read as follows:


          (a) Disclosure.  To Seller's Knowledge, the representations and
              ----------
     warranties set forth in this Section 4.1 of this Agreement, the exhibits to
     this Agreement, and the information, documents and Balance Sheets provided
     under the terms of this Agreement represent full and fair disclosure as of
     the date of this Agreement and do not contain any untrue statement of any
     material fact or omit any material fact necessary in order to make the
     facts stated not misleading.

     b.   Paragraph (e) of Section 4.2 of the Agreement is amended and restated
     in its entirety to read as follows:

          (e) Investment Intent.  The Common Stock and the Membership Interests
              -----------------
     are being purchased for Buyer's own account and not with a view to, or for
     resale in connection with, any distribution or public offering thereof
     within the meaning of the Securities Act.  Buyer understands that the
     Common Stock and the Membership Interests have not been registered under
     the Securities Act by reason of their issuance in transactions exempt from
     the registration and prospectus delivery requirements of the Securities Act
     pursuant to Section 4(2) thereof. Buyer is knowledgeable, competent, and


     experienced in the oil and gas industry and has independently evaluated and
     interpreted the technical data and other information regarding the
     Operating Assets prior to entering into this Agreement, understands and is
     financially able to bear the risk associated with ownership of the
     Subsidiaries and the Partnership, and will independently conduct all the
     due diligence investigations and reviews of all matters concerning the
     Subsidiaries, the Partnership and the Operating Assets as it deems
     necessary prior to Closing. Buyer acknowledges that Buyer is not relying
     upon any statement or representations made by Seller concerning the present
     or future value of, or anticipated income, costs, or profits, if any, to be
     derived from, the Subsidiaries, the Partnership or the Operating Assets,
     and Buyer has relied solely upon its independent inspections, estimates,
     computations, evaluations, reports, studies, knowledge and other
     information regarding the Subsidiaries, the Partnership and the Operating
     Assets.

     c.   The following Section 4.3 shall be added to the Agreement as follows:

     4.3  Seller's Representations and Warranties to Be Made at Closing.
          -------------------------------------------------------------
     Effective as of the Closing Date, Seller shall represent and warrant that:

     (a)  Disclosure.  To Seller's Knowledge, the representations and warranties
          ----------
     set forth in this Section 4.3, the exhibits to this Agreement, and the
     information, documents and Balance Sheets provided under the terms of this
     Agreement represent full and fair disclosure as of the Closing Date and do
     not contain any untrue statement of any material fact or omit any material
     fact necessary in order to make the facts stated not misleading.

     (b)  Authorization and Enforceability.
          --------------------------------

               (i)    This Agreement and the Transaction have been duly
                      authorized by each Seller.

               (ii)   Neither the execution and delivery of this Agreement by
                      Seller, nor the consummation by Seller of the transactions
                      contemplated hereby, will violate or conflict with, or
                      result in the acceleration of rights, benefits or
                      obligations under, (1) any provision of any Seller's,
                      Subsidiary's, Partnership's or Starr Partnership's
                      respective Charters, Bylaws, management agreements,
                      limited liability company agreements, operating agreements
                      or partnership agreements, or (2) any applicable statute,
                      law, regulation or Governmental Order to which Seller or
                      the Subsidiaries or the Partnerships or the assets and
                      properties of such entities, including without limitation
                      the Operating Assets, are bound or subject.

               (iii)  This Agreement has been duly executed and delivered by
                      each Seller and constitutes the valid and binding
                      obligation of each Seller, enforceable against it in
                      accordance with its terms, except as such enforceability
                      may be limited by bankruptcy, insolvency or other laws
                      relating to or affecting the enforcement of creditors'
                      rights generally and general principles of equity
                      (regardless of


                      whether such enforceability is considered in a proceeding
                      in equity or at law).

               (iv)   Except as set forth on Schedule 4.1(b)(iv), or as
                      otherwise specifically provided herein, the execution,
                      delivery, and performance of this Agreement (assuming that
                      all applicable consents are received and all applicable
                      Preferential Rights to Purchase individual Operating
                      Assets are waived) will not (A) be in violation of any
                      provisions of any regulation or order that could
                      reasonably be expected to adversely affect the ownership
                      or operations of the Operating Asset affected thereby or
                      give rise to damages, penalties or claims of third
                      parties, or (B) result in the breach of, or constitute a
                      default under, any indenture or other material agreement
                      or instrument to which any Seller, Subsidiary, Partnership
                      or Starr Partnership is bound.

               (v)    Except as set forth on Schedule 4.1(b)(v) or as otherwise
                      specifically provided herein, no consent, waiver,
                      approval, order or authorization of, notice to, or
                      registration, declaration, designation, qualification or
                      filing with, any Governmental Authority or third Person,
                      domestic or foreign, is or has been or will be required on
                      the part of Seller in connection with the execution and
                      delivery of this Agreement or the consummation by Seller
                      of the transactions contemplated hereby or thereby, other
                      than (A) consents and Preferential Rights to Purchase
                      affecting individual Operating Assets; (B) filings
                      required (1) to form Grande and Southeast under Delaware
                      law, (2) to convert Reserves into Reserves LLC under
                      Delaware law and (3) to convert Exploration into
                      Exploration LLC under Delaware law; (C) tax filings or (D)
                      where the failure to obtain such consents, waivers,
                      approvals, orders or authorizations or to make or effect
                      such registrations, declarations, designations,
                      qualifications or filings (1) is not reasonably likely to
                      prevent or materially delay consummation of the
                      transactions contemplated by this Agreement (2) could
                      reasonably be expected to adversely affect the Business or
                      (3) could give rise to damages, penalties or claims of
                      third parties.


          (c)  Organizational Status.
               ---------------------

               (i)    Each Seller: (1) is a corporation duly organized, validly
                      existing and in good standing under the laws of Delaware,
                      (2) is duly qualified to transact business in each
                      jurisdiction where the nature and extent of its business
                      and properties require such qualification, and (3)
                      possesses all requisite authority and power to conduct its
                      business and execute, deliver and comply with the terms
                      and provisions of this Agreement and to perform all of its
                      obligations hereunder. There are no pending or threatened
                      Actions (or basis therefor) for the dissolution,
                      liquidation, insolvency, or rehabilitation of any Seller.

               (ii)   Exploration LLC (1) is a limited liability company duly
                      organized, validly existing and in good standing under the
                      laws of Delaware, (2) is duly qualified to transact
                      business in each jurisdiction where the nature and extent
                      of its business and properties require such qualification,
                      and (3) possesses all requisite authority and power to
                      conduct its business. There are no pending or threatened
                      Actions (or basis therefor) for the dissolution,
                      liquidation, insolvency, or rehabilitation of Exploration
                      LLC.

               (iii)  Reserves LLC (1) is a limited liability company duly
                      organized, validly existing and in good standing under the
                      laws of Delaware, (2) is duly qualified to transact
                      business in each jurisdiction where the nature and extent
                      of its business and properties require such qualification,
                      and (3) possesses all requisite authority and power to
                      conduct its business. There are no pending or threatened
                      Actions (or basis therefor) for the dissolution,
                      liquidation, insolvency, or rehabilitation of Reserves
                      LLC.

               (iv)   Grande(1) is a limited liability company duly organized,
                      validly existing and in good standing under the laws of
                      Delaware, (2) is duly qualified to transact business in
                      each jurisdiction where the nature and extent of its
                      business and properties require such qualification, and
                      (3) possesses all requisite authority and power to conduct
                      its business. There are no pending or threatened Actions
                      (or basis therefor) for the dissolution, liquidation,
                      insolvency, or rehabilitation of Grande.

               (v)    Southeast (1) is a limited liability company duly
                      organized, validly existing and in good standing under the
                      laws of Delaware, (2) is duly qualified to transact
                      business in each jurisdiction where the nature and extent
                      of its business and properties require such qualification,
                      and (3) possesses all requisite authority and power to
                      conduct its business. There are no pending or threatened
                      Actions (or basis therefor) for the dissolution,
                      liquidation, insolvency, or rehabilitation of Southeast.


               (vi)   The E&P Partnership (1) is a limited partnership duly
                      organized, validly existing and in good standing under the
                      laws of Delaware, (2) is duly qualified to transact
                      business in each jurisdiction where the nature and extent
                      of its business and properties require such qualification,
                      and (3) possesses all requisite authority and power to
                      conduct its business. There are no pending or threatened
                      Actions (or basis therefor) for the dissolution,
                      liquidation, insolvency, or rehabilitation of the E&P
                      Partnership.

               (vii)  The Pipeline Partnership (1) is a limited partnership duly
                      organized, validly existing and in good standing under the
                      laws of Delaware, (2) is duly qualified to transact
                      business in each jurisdiction where the nature and extent
                      of its business and properties require such qualification,
                      and (3) possesses all requisite authority and power to
                      conduct its business. There are no pending or threatened
                      Actions (or basis therefor) for the dissolution,
                      liquidation, insolvency, or rehabilitation of the Pipeline
                      Partnership.

               (viii) Gathering (1) is a corporation duly organized, validly
                      existing and in good standing under the laws of Delaware,
                      (2) is duly qualified to transact business in each
                      jurisdiction where the nature and extent of its business
                      and properties require such qualification, and (3)
                      possesses all requisite authority and power to conduct its
                      business. There are no pending or threatened Actions (or
                      basis therefor) for the dissolution, liquidation,
                      insolvency, or rehabilitation of Gathering.

               (ix)   Natural Gas (1) is a corporation duly organized, validly
                      existing and in good standing under the laws of Delaware,
                      (2) is duly qualified to transact business in each
                      jurisdiction where the nature and extent of its business
                      and properties require such qualification, and (3)
                      possesses all requisite authority and power to conduct its
                      business. There are no pending or threatened Actions (or
                      basis therefor) for the dissolution, liquidation,
                      insolvency, or rehabilitation of Natural Gas.

               (x)    Starr-Zapata Partnership (1) is a general partnership duly
                      formed and validly existing under the laws of Texas and
                      (2) possesses all requisite authority and power to conduct
                      its business. To Seller's Knowledge, there are no pending
                      or threatened Actions (or basis therefor) for the
                      dissolution, liquidation, insolvency, or rehabilitation of
                      Starr-Zapata Partnership.

               (xi)   Starr County Gathering System (1) is a general partnership
                      duly formed and validly existing under the laws of Texas
                      and (2) possesses all requisite authority and power to
                      conduct its business. To Seller's Knowledge, there are no
                      pending or threatened Actions (or basis therefor) for the



                      dissolution, liquidation, insolvency, or rehabilitation of
                      Starr County Gathering System.

          (d)  Subsidiary and Other Equity Interests.
               -------------------------------------

               (i)    Exploration LLC has no subsidiaries and does not own any
                      stock or other interest in any other corporation,
                      partnership, joint venture, or other business entity, with
                      the exception of the E&P Partnership.

               (ii)   Reserves LLC has no subsidiaries and does not own any
                      stock or other interest in any other corporation,
                      partnership, joint venture, or other business entity, with
                      the exception of the E&P Partnership.

               (iii)  Grande has no subsidiaries and does not own any stock or
                      other interest in any other corporation, partnership,
                      joint venture, or other business entity, with the
                      exception of the E&P Partnership.

               (iv)   Southeast has no subsidiaries and does not own any stock
                      or other interest in any other corporation, partnership,
                      joint venture, or other business entity, with the
                      exception of the E&P Partnership.

               (v)    The E&P Partnership has no subsidiaries and does not own
                      any stock or other interest in any other corporation,
                      partnership, joint venture, or other business entity.

               (vi)   Natural Gas has no subsidiaries and does not own any stock
                      or other interest in any other corporation, partnership,
                      joint venture, or other business entity, with the
                      exception of the Pipeline Partnership and the Starr
                      Partnerships.

               (vii)  Gathering has no subsidiaries and does not own any stock
                      or other interest in any other corporation, partnership,
                      joint venture, or other business entity, with the
                      exception of the Pipeline Partnership.

               (viii) The Pipeline Partnership has no subsidiaries and does not
                      own any stock or other interest in any other corporation,
                      partnership, joint venture, or other business entity, with
                      the exception of the Starr Partnerships.

               (ix)   Starr-Zapata Pipe Line has no subsidiaries and does not
                      own any stock or other interest in any other corporation,
                      partnership, joint venture, or other business entity.

               (ix)   Starr County Gathering System has no subsidiaries and does
                      not own any stock or other interest in any other
                      corporation, partnership, joint venture, or other business
                      entity

          (e)  Membership Interests and Partnership Interests.
               -----------------------------------------------


               (i)    Exploration LLC has authorized membership interests, of
                      which all are issued and outstanding and owned by Tesoro
                      Gas Resources Company, Inc. The membership interests of
                      Exploration LLC have been duly authorized by Exploration
                      LLC, and the membership interests of Exploration LLC owned
                      by Tesoro Gas Resources Company, Inc. are validly issued
                      and outstanding, fully paid and nonassessable. There are
                      no preemptive rights, or authorized or outstanding
                      subscriptions, options, consents to assignment or rights
                      of first refusal, convertible securities, warrants, calls,
                      stock appreciation rights, phantom stock, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller or Exploration
                      LLC to issue or to transfer (or preventing the transfer
                      of) any membership interests, capital stock or other
                      equity interest in Exploration LLC.

               (ii)   Reserves LLC has authorized membership interests, of which
                      all are issued and outstanding and owned by Tesoro Gas
                      Resources Company, Inc. The membership interests of
                      Reserves LLC have been duly authorized by Reserves, and
                      the membership interests of Reserves LLC owned by Tesoro
                      Gas Resources Company, Inc. are validly issued and
                      outstanding, fully paid and nonassessable. There are no
                      preemptive rights, subscriptions, options, consents to
                      assignment or rights of first refusal, convertible
                      securities, warrants, calls, stock appreciation rights,
                      phantom stock, profit participation, or other similar
                      rights, or other agreements or commitments obligating
                      Seller or Reserves LLC to issue or to transfer (or
                      preventing the transfer of) any membership interests,
                      capital stock or other equity interest in Reserves LLC.

               (iii)  Grande has authorized membership interests, of which all
                      are issued and outstanding and owned by Tesoro Gas
                      Resources Company, Inc. The membership interests of Grande
                      have been duly authorized by Grande, and the membership
                      interests of Grande owned by Tesoro Gas Resources Company,
                      Inc. are validly issued and outstanding, fully paid and
                      nonassessable. There are no preemptive rights,
                      subscriptions, options, consents to assignment or rights
                      of first refusal, convertible securities, warrants, calls,
                      stock appreciation rights, phantom stock, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller or Grande to
                      issue or to transfer (or preventing the transfer of) any
                      membership interests, capital stock or other equity
                      interest in Grande.

               (iv)   Southeast has authorized membership interests, of which
                      all are issued and outstanding and owned by Tesoro Gas
                      Resources Company, Inc. The membership interests of
                      Southeast have been duly authorized by Southeast, and the
                      membership interests of


                      Southeast owned by Tesoro Gas Resources Company, Inc. are
                      validly issued and outstanding, fully paid and
                      nonassessable. There are no preemptive rights,
                      subscriptions, options, consents to assignment or rights
                      of first refusal, convertible securities, warrants, calls,
                      stock appreciation rights, phantom stock, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller or Southeast
                      to issue or to transfer (or preventing the transfer of)
                      any membership interests, capital stock or other equity
                      interest in Southeast.

               (v)    In the E&P Partnership, the entire Series A limited
                      partnership interest is held by Reserves LLC, the entire
                      Series B limited partnership interest is held by Grande,
                      the entire Series C limited partnership interest is held
                      by Southeast, and the general partnership interest is held
                      by Exploration LLC. Such interests are duly authorized
                      under the agreement governing the E&P Partnership, as
                      currently amended, and are valid. There are no preemptive
                      rights, or authorized or outstanding subscriptions,
                      options, consents to assignment or rights of first
                      refusal, convertible securities, warrants, calls,
                      appreciation rights, phantom interests, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller, the
                      Partnership, Reserves LLC, Grande, LLC, Southeast, LLC or
                      Exploration to issue or to transfer (or preventing the
                      transfer of) any equity interest in the E&P Partnership.

               (vi)   Seller has delivered to Buyer correct and complete copies
                      of each Subsidiary's, each Partnership's and each Starr
                      Partnership's respective Charter, Bylaws, organizational
                      documents, management agreement, limited liability company
                      agreement, operating agreement or partnership agreement,
                      as amended to date, and the minute books of each
                      Subsidiary and Partnership. No Subsidiary, Partnership or
                      Starr Partnership is in breach of any provision of its
                      Charter, Bylaws organizational documents, management
                      agreement, limited liability company agreement, operating
                      agreement or partnership agreement.

               (vii)  Natural Gas has authorized capital stock consisting of
                      1,000 shares of $1.00 par value common stock, of which
                      1,000 shares are issued and outstanding, with all of such
                      shares owned by Tesoro Petroleum Corporation. The common
                      stock has been duly authorized by Natural Gas and the
                      shares owned by Tesoro Petroleum Corporation are validly
                      issued and outstanding, fully paid and nonassessable.
                      There are no preemptive rights, or authorized or
                      outstanding subscriptions, options, consents to assignment
                      or rights of first refusal, convertible securities,
                      warrants, calls, stock appreciation rights, phantom stock,
                      profit


                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller or Natural Gas
                      to issue or to transfer (or preventing the transfer of)
                      any common stock or other equity interest in Natural Gas.

               (viii) Gathering has authorized capital stock consisting of 1,000
                      shares of $1.00 par value common stock, of which 1,000
                      shares are issued and outstanding, with all of such shares
                      owned by Tesoro Gas Resources Company, Inc. The common
                      stock has been duly authorized by Gathering, and the
                      shares owned by Tesoro Gas Resources Company, Inc. are
                      validly issued and outstanding, fully paid and
                      nonassessable. There are no preemptive rights,
                      subscriptions, options, consents to assignment or rights
                      of first refusal, convertible securities, warrants, calls,
                      stock appreciation rights, phantom stock, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller or Gathering
                      to issue or to transfer (or preventing the transfer of)
                      any common stock or other equity interest in Gathering.

               (ix)   In the Pipeline Partnership, a 99% limited partnership
                      interest is held by Gathering, and a 1% general
                      partnership interest is held by Natural Gas. Such
                      interests are duly authorized under the agreement forming
                      the Pipeline Partnership and are valid. There are no
                      preemptive rights, or authorized or outstanding
                      subscriptions, options, consents to assignment or rights
                      of first refusal, convertible securities, warrants, calls,
                      appreciation rights, phantom interests, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller, the Pipeline
                      Partnership, Natural Gas or Gathering to issue or to
                      transfer (or preventing the transfer of) any equity
                      interest in the Pipeline Partnership.

               (x)    In Starr County Gathering, a 69% general partnership
                      interest is held by Pipeline, a 1% general partnership
                      interest is held by Natural Gas, and a 30% general
                      partnership interest is held by Coastal. Such interests
                      have been duly authorized under the agreement forming
                      Starr County Gathering, and are valid. Except as set forth
                      in the Starr County Joint Venture Agreement, there are no
                      preemptive rights, or authorized or outstanding
                      subscriptions, options, consents to assignment or rights
                      of first refusal, convertible securities, warrants, calls,
                      appreciation rights, phantom interests, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller, the Pipeline
                      Partnership, Natural Gas, Starr County Gathering, or, to
                      Seller's Knowledge, Coastal, to issue or to transfer (or
                      preventing the transfer of) any equity interest in Starr
                      County Gathering.


               (xi)   In the Starr-Zapata Partnership, a 49% general partnership
                      interest is held by Pipeline, a 1% general partnership
                      interest is held by Natural Gas, and a 50% general
                      partnership interest is held by Coastal. Such interests
                      have been duly authorized under the agreement forming the
                      Starr-Zapata Partnership, and are valid. Except as set
                      forth in the Starr-Zapata Partnership Agreement, there are
                      no preemptive rights, or authorized or outstanding
                      subscriptions, options, consents to assignment or rights
                      of first refusal, convertible securities, warrants, calls,
                      appreciation rights, phantom interests, profit
                      participation, or other similar rights, or other
                      agreements or commitments obligating Seller, the Pipeline
                      Partnership, Natural Gas, Starr County Gathering, or, to
                      Seller's Knowledge, Coastal to issue or to transfer (or
                      preventing the transfer of) any equity interest in Starr
                      County Gathering.

               (f)    Title to Stock, Partnership Interests and Assets.
                      ------------------------------------------------

               (i)    All of the issued and outstanding membership interests of
                      Exploration LLC, Reserves LLC, Grande and Southeast, which
                      consist only of the Membership Interests, are owned of
                      record and beneficially with good and valid title by
                      Tesoro Gas Resources Company, Inc., free and clear of any
                      Encumbrance. Upon delivery to E&P Buyer of the
                      certificates for the Membership Interests in the manner
                      and with the powers described in Section 12.2(b), assuming
                      that E&P Buyer pays the consideration contemplated by this
                      Agreement and has no notice of any adverse claim, good and
                      valid title to the Membership Interests will have been
                      transferred to E&P Buyer, free and clear of any
                      Encumbrances. Neither Tesoro Petroleum Corporation nor
                      Tesoro Gas Resources Company, Inc. has received any notice
                      of any adverse claim to their interests in and to the
                      title to the Membership Interests.

               (ii)   All of the issued and outstanding partnership interests in
                      the E&P Partnership are owned of record and beneficially
                      with good and valid title by Reserves LLC, Grande,
                      Southeast and Exploration LLC as described in Section
                      4.3(e)(v), free and clear of any Encumbrance. Neither
                      Reserves LLC, Grande, Southeast nor Exploration LLC has
                      received any notice of any adverse claim to their
                      respective interests in the Partnership.

               (iii)  Each Subsidiary and Partnership has good title to all of
                      the assets and properties (except the Operating Assets)
                      which it owns or purports to own, including the Financial
                      Assets and Liabilities reflected on the Balance Sheets,
                      except for properties sold, consumed or otherwise disposed
                      of in the ordinary course of business since the date of
                      the Balance Sheets, free and clear of any Encumbrances
                      other than Permitted Encumbrances.


               (iv)   All of the issued and outstanding shares of capital stock
                      of Natural Gas and Gathering, which consist only of the
                      Common Stock, are owned of record and beneficially by
                      Tesoro Petroleum Corporation and Tesoro Gas Resources
                      Company, Inc., respectively, free and clear of any
                      Encumbrance. Upon delivery to Pipeline Buyer in the manner
                      and with the powers described in Section 12.2(a) of the
                      certificates for the Common Stock of Natural Gas and
                      Gathering, assuming that Pipeline Buyer pays the
                      consideration contemplated by the Agreement and has no
                      notice of any adverse claim, good and valid title to the
                      Common Stock represented by such certificate will have
                      been transferred to Buyer, free and clear of any
                      Encumbrances. Neither Tesoro Petroleum Corporation nor
                      Tesoro Gas Resources Company, Inc. has received any notice
                      of any adverse claim to their respective title to the
                      Common Stock.

               (v)    All of the issued and outstanding partnership interests in
                      the Pipeline Partnership are owned of record and
                      beneficially with good and valid title by Natural Gas and
                      Gathering, free and clear of any Encumbrance. Neither
                      Natural Gas nor Gathering has received any notice of any
                      adverse claim to their respective interests in the
                      Pipeline Partnership.

               (vi)   All of the issued and outstanding partnership interests in
                      the Starr Partnerships are owned of record and
                      beneficially with good and valid title by Pipeline,
                      Natural Gas and Coastal, and with respect to Pipeline and
                      Natural Gas, free and clear of any Encumbrance. Neither
                      Natural Gas nor Pipeline has received any notice of any
                      adverse claim to their respective interests in the Starr
                      Partnerships.

          (g)  Litigation.  Except as set forth in Schedule 4.1(g), no Seller,
               ----------
     Subsidiary, Partnership or Starr Partnership has been served with and, to
     Seller's Knowledge, there are no pending or threatened Actions before any
     Governmental Authority against or affecting any Seller, Subsidiary,
     Partnership or Starr Partnership or any of the Operating Assets, which, if
     adversely determined, either would be reasonably expected to expose any
     Subsidiary, Partnership or Starr Partnership to a risk of loss of greater
     than $100,000 after the Effective Time or would interfere with Seller's
     ability or right to execute and deliver this Agreement or consummate the
     transactions contemplated by this Agreement.

          (h)  Labor Matters.  Except as set forth on Schedule 4.1(h), there are
               -------------
     no contracts, agreements, or other arrangements whereby the Subsidiaries or
     the Partnership are obligated to compensate or provide health and welfare
     benefit plans or retirement benefits to any employees or other persons,
     except for employment agreements that are terminable at will, without
     breach or penalty. To Sellers' Knowledge, each Seller, Subsidiary,
     Partnership and Starr Partnership is in compliance with all federal, state,
     and local laws respecting employment and employment practices, terms and
     conditions of employment, and wages and hours and is not engaged in any
     unfair labor practice with regard to those persons employed in connection
     with a Subsidiary's, Partnership's or Starr Partnership's operations. No
     employee of any Subsidiary, Partnership or Starr


     Partnership is covered under any collective bargaining agreement. There is
     no unfair labor practice complaint against any Subsidiary, Partnership or
     Starr Partnership pending or, to Seller's Knowledge, threatened before the
     National Labor Relations Board or any comparable state or local
     Governmental Authority. There is no labor strike, slowdown or work stoppage
     pending or, to Seller's Knowledge, threatened against or directly affecting
     a Subsidiary, Partnership or Starr Partnership and no grievance or any
     Action arising out of or under collective bargaining agreements is pending
     or, to Seller's Knowledge, threatened against any Subsidiary, Partnership
     or Starr Partnership.

          (i)  Taxes.
               -----

               (i)    Except as set forth in Schedule 4.1(i), each Seller,
                      Subsidiary and Partnership has timely filed or caused to
                      be timely filed (or will timely file or cause to be timely
                      filed) with the appropriate Taxing Authorities all Tax
                      Returns required to be filed on or prior to the Closing
                      Date by or with respect to such Subsidiary or Partnership
                      (or their respective Operating Assets) and has timely paid
                      or adequately provided for (or will timely pay or
                      adequately provide for) all Taxes shown thereon as owing,
                      except where the failure to file such Tax Returns or pay
                      any such Taxes would not, or could not reasonably be
                      expected to, in the aggregate, result in losses or costs
                      or expenses to the Subsidiaries, the Partnership and the
                      Starr Partnerships in excess of $100,000 after the Closing
                      Date.

               (ii)   Sellers and the Subsidiaries are members of an affiliated
                      group of corporations which file consolidated federal
                      income tax returns ("Tesoro Group") with Tesoro Petroleum
                      Corporation as the common parent ("Tesoro Parent"). The
                      Tesoro Group has been subject to normal and routine
                      audits, examinations and adjustments of Taxes from time to
                      time, but there are no current audits or audits for which
                      written notification has been received (in either case,
                      with respect to or which include the Subsidiaries), other
                      than those set forth in Schedule 4.1(i). There are no
                      written agreements with any Taxing Authority with respect
                      to or including the Subsidiaries which will in any way
                      affect the Subsidiaries' liability for Taxes after the
                      Closing Date.

               (iii)  Except as set forth in Schedule 4.1(i), no assessment,
                      deficiency or adjustment for any Taxes has been asserted
                      in writing or, to the knowledge of Sellers, is proposed
                      with respect to any Tax Return of, or which includes, the
                      Subsidiaries.

               (iv)   Except as set forth in Schedule 4.1(i), there is not in
                      force any extension of time with respect to the due date
                      for the filing of any Tax Return of or with respect to or
                      which includes the Subsidiaries or any waiver or agreement
                      for any extension of time for the assessment or payment of
                      any Tax of or with respect to or which includes the
                      Subsidiaries.


               (v)    Except for Taxes due with respect to Tax Returns that will
                      be paid by Tesoro Parent (and not subject to reimbursement
                      by the Subsidiaries), the accounting records of the
                      Subsidiaries will include immediately prior to the Closing
                      Date adequate provisions for the payment of all Taxes of
                      the Subsidiaries for all taxable periods or portions
                      thereof through the Closing Date.

               (vi)   All Tax allocation or sharing agreements or arrangements
                      have been or will be canceled on or prior to the Closing
                      Date. No payments are or will become due by the
                      Subsidiaries after the Closing Date pursuant to any such
                      agreement or arrangement.

               (vii)  Except as set forth on Schedule 4.1(i), none of the
                      Sellers or the Subsidiaries will, as a result of the
                      transactions contemplated by this Agreement, be obligated
                      to make a payment after the Closing Date to an individual
                      that would be a "parachute payment" as defined in Section
                      280G of the Code without regard to whether such payment is
                      reasonable compensation for personal services performed or
                      to be performed in the future.

               (viii) The Subsidiaries have not participated in or cooperated
                      with an international boycott within the meaning of
                      Section 999 of the Code.

               (ix)   No Subsidiary has filed a consent under Code Section
                      341(f) concerning collapsible corporations.

               (x)    No Subsidiary or Partnership has been a United States real
                      property holding corporation within the meaning of Code
                      Section 897(c)(2) during the applicable period specified
                      in Code Section 897(c)(1)(A)(ii).

               (xi)   All monies required to be withheld by either Seller, any
                      Subsidiary or any Partnership and paid to Taxing
                      Authorities for all Taxes have been (i) collected or
                      withheld and either paid to the respective Taxing
                      Authorities or set aside in accounts for such purpose or
                      (ii) properly reflected in the Balance Sheets.

          (j)  Balance Sheets.
               --------------

               (i)    The Balance Sheets have been prepared in accordance with
                      GAAP applied on a basis consistent with prior periods,
                      except as described in the notes thereto, which will
                      reflect that the Partnership and the Subsidiaries have
                      been accounted for as part of a consolidated financial
                      group with their affiliates and not as completely separate
                      stand-alone entities.

               (ii)   The Balance Sheets present fairly, in all material
                      respects, the financial condition of the combined
                      Partnership and the Subsidiaries as of June 30, 1999. The
                      books and records of the


                      Subsidiaries and the Partnership from which the Balance
                      Sheets were prepared were complete and accurate in all
                      material respects at the time of such preparation.

               (iii)  Each Subsidiary and Partnership has no Liabilities, except
                      for Liabilities (1) reflected in the Balance Sheets, (2)
                      incurred by the Subsidiaries or the Partnership in the
                      ordinary course of business and consistent with past
                      practices since the date of the Balance Sheets, or (3)
                      which are Permitted Encumbrances, (4) for which the Buyer
                      is being indemnified hereunder, or (5) which individually
                      amount to a loss or liability of not greater than $100,000
                      or in the aggregate amount to a loss or liability of not
                      greater than $250,000. As used in this subparagraph, the
                      term "Liabilities" excludes any Liabilities not required
                      to be reflected in the Balance Sheets under GAAP.

          (k)  Absence of Certain Changes. Except as set forth in Schedule
               --------------------------
     4.1(k), or as otherwise contemplated by this Agreement (including without
     limitation Sections 2.5, 2.6, 9.4(b) and 10.6), since the close of business
     on June 30, 1999:

               (i)    no Subsidiary, Partnership or Starr Partnership has sold,
                      leased, transferred, or assigned any assets other than
                      surplus equipment not necessary for operations of the
                      Business having a value less than $25,000 and for a
                      reasonable consideration;

               (ii)   no Subsidiary, Partnership or Starr Partnership has
                      incurred, assumed or become subject to any additional
                      indebtedness for money borrowed or purchase money
                      indebtedness, including capitalized leases;

               (iii)  no Subsidiary, Partnership or Starr Partnership has
                      entered into any transaction not in the ordinary course of
                      business, except as contemplated by this Agreement;

               (iv)   there have been no additional Encumbrances placed on the
                      assets of any Subsidiary, Partnership or Starr Partnership
                      other than Permitted Encumbrances;

               (v)    no event has occurred which constitutes a Material Adverse
                      Effect;

               (vi)   no Subsidiary, Partnership or Starr Partnership has made
                      any loan to, or entered into any contract with (other than
                      severance agreements for which Seller shall remain
                      responsible), any of its directors or officers;

               (vii)  no Subsidiary has issued, sold, or otherwise disposed of
                      any of its interests in any Partnership, and no Subsidiary
                      or Partnership has issued, sold or otherwise disposed of
                      any of its interests in any Starr Partnership;


               (viii)  there has been no change made or authorized to the
                       Charter, Bylaws or Partnership Agreement of any
                       Subsidiary, Partnership or Starr Partnership;

               (ix)    no Subsidiary, Partnership or Starr Partnership has
                       canceled, compromised, waived, or released any debt or
                       Action (or series of related debts or Actions) involving
                       more than fifty thousand dollars ($50,000);

               (x)     no Subsidiary, Partnership or Starr Partnership has
                       delayed or postponed the payment of accounts payable or
                       other Liabilities owed either involving more than $50,000
                       (individually or in the aggregate), other than amounts
                       which Seller reasonably and in good faith disputes;

               (xi)    no Subsidiary, Partnership or Starr Partnership has made
                       any capital investment in, any loan to, or any
                       acquisition of the securities or assets of, any other
                       Person (or series of related capital investments, loans,
                       and acquisitions) involving more than $50,000;

               (xii)   no Subsidiary, Partnership or Starr Partnership has made
                       any capital expenditure (or series of related capital
                       expenditures) involving more than $50,000, except in
                       connection with operations conducted pursuant to Section
                       9.2(f);

               (xiii)  no Subsidiary, Partnership or Starr Partnership has
                       entered into any Contract (or series of related
                       Contracts) involving more than $50,000 other than (i) to
                       effectuate operations set forth on Schedule 9.2(f) or
                       (ii) constituting joint operating agreements or oil and
                       gas leases entered into in the ordinary course of
                       business or (iii) contracts with officers and directors
                       for which the Seller shall remain responsible;

               (xiv)   to Seller's Knowledge, no Subsidiary, Partnership or
                       Starr Partnership has materially breached any Contract by
                       which it is bound or to which any of its assets is
                       subject; and

               (xv)    no Subsidiary or Partnership has declared, set aside, or
                       paid any dividend or made any distribution with respect
                       to its interests in any Partnership or Starr Partnership
                       (whether in cash or in kind) or redeemed, purchased, or
                       otherwise acquired any of its interests in any
                       Partnership or Starr Partnership, other than in the
                       ordinary course of business or as contemplated by this
                       Agreement.

          (l)  Compliance With Law. Since June 30, 1999, no Subsidiary,
               -------------------
     Partnership or Starr Partnership has violated any law, statute or
     regulation which have subjected them to fines or penalties (nor to Seller's
     Knowledge have any third parties violated any Applicable Law for which any
     Subsidiary, Partnership or Starr Partnership may have any responsibility)
     that individually or in the aggregate exceed $100,000. As of the date of
     this Agreement, to Seller's Knowledge, each Subsidiary, Partnership and
     Starr


     Partnership is in compliance in all material respects with all laws,
     statutes or regulations applicable to such Subsidiary, Partnership and
     Starr Partnership, except where the noncompliance with which would not, in
     the aggregate, result in the imposition on the Subsidiaries, the
     Partnership and the Starr Partnerships of fines or penalties that
     individually or in the aggregate could reasonably be expected to exceed
     $100,000.

          (m)  Operating Assets.
               ----------------

               (i)   Seller represents that as of Closing, each Seller's,
                     Partnership's and Starr Partnership's interest in the
                     Operating Assets shall be free and clear of any liens other
                     than Permitted Encumbrances.

               (ii)  To Seller's Knowledge, the Operating Assets are being
                     operated in compliance in all material respects with all
                     applicable federal, state or local laws, and the rules and
                     regulations of any agency or authority having jurisdiction.

               (iii) Except as set forth in Schedule 4.1(m)(iii), each
                     Subsidiary, Partnership and Starr Partnership possess all
                     permits, licenses, orders, approvals and authorizations
                     required by any applicable law, statute, regulation or
                     Governmental Order, or by the property and contract rights
                     of third Persons, reasonably necessary to permit the
                     operation of the Business in the manner currently conducted
                     by the Subsidiaries, the Partnership and the Starr
                     Partnerships, except where the failure to possess such
                     permit, license, order, approval, authorization or rights
                     would not result in losses, costs or expenses to the
                     Subsidiaries, the Partnership and the Starr Partnerships,
                     in the aggregate, in excess of $100,000. No Subsidiary,
                     Partnership or Starr Partnership has received written
                     notice from any Governmental Authority that any such
                     permit, license, order, approval or authorization has been,
                     or will be, revoked or terminated.

               (iv)  Except as set forth in Schedule 4.1(m)(iv), immediately
                     before the Closing Date, the Subsidiaries, the Partnership
                     and the Starr Partnerships will hold or have the right to
                     use in the Business all of the assets and properties
                     (including all licenses and agreements) currently being
                     used (except those disposed of or expiring in the ordinary
                     course of business or otherwise as contemplated or
                     permitted by this Agreement) or which are reasonably
                     necessary to permit the operation of the Business in the
                     manner currently conducted by the Subsidiaries, the
                     Partnership and the Starr Partnerships. Since June 30,
                     1999, the Subsidiaries, the Partnership and the Starr
                     Partnerships have conducted no business other than the
                     Business.

          (n)  No Brokers' Fees. Except for Credit Suisse First Boston, the fees
               ----------------
     and expenses of which will be paid by Seller, neither Seller nor any of its
     directors, officers or employees has employed any broker, finder or
     investment banker or incurred any


     Liability for any brokerage fees, commissions, finders' fees or similar
     fees in connection with the transactions contemplated by this Agreement.
     Buyer shall have no responsibility whatsoever, contingent or otherwise, for
     any brokers' or finders' fees incurred by any Seller, Subsidiary or
     Partnership relating to the Transaction.

          (o) Suspense Funds. Schedule 4.1(o) is a true and correct list as of
              --------------
     August 31, 1999 of all amounts held by the E&P Partnership and/or the
     Subsidiaries in suspense accounts, or otherwise, related to the Properties
     for the benefit or account of any other Person.

          (p) Insurance. As listed on Schedule 4.1(p) Seller, the Subsidiaries,
              ---------
     the Partnership and the Starr Partnerships maintain insurance on and bonds
     with respect to the Operating Assets, as set forth on Schedule 4.1(p),
     covering such risks and with such deductible amounts as are consistent with
     general oil and gas industry practice.

          (q) Contracts on Production. Except as set forth on Schedule 4.1(q),
              -----------------------
     there are no Contracts involving the purchase, marketing, brokering or sale
     of Production that require a dedication of Production for a term in excess
     of  three (3) months that will not be terminable without penalty or other
     liability at the sole discretion of the Subsidiaries or the Partnership
     upon not more than one (1) month's notice, except for commitments under
     operating agreements.

          (r) Equipment. Since June 30, 1999, neither Seller, the Subsidiaries,
              ---------
     any Partnership nor the Starr Partnerships, nor to Seller's Knowledge the
     operator of any of the Operating Assets, has removed any of the equipment,
     facilities or other property  from the Operating Assets except in the
     ordinary course of business.

          (s) Tax Partnerships. Except as disclosed in Schedule 4.1(s), no
              ----------------
     Property is subject to, or considered to be held by, any partnership for
     federal income tax purposes, other than tax partnerships under joint
     operating agreements.

          (t) Disclaimer. Except as otherwise expressly set forth in this
              ----------
     Article and elsewhere in this Agreement, Seller and the Affiliates of
     Seller expressly disclaim any representations or warranties of any kind or
     nature, express or implied, as to the condition, value or quality of the
     assets or properties currently or formerly used, operated, owned, leased,
     controlled, possessed, occupied or maintained by the Subsidiaries or the
     Partnership, and SELLERS AND ALL OTHER TESORO AFFILIATES SPECIFICALLY
     DISCLAIM ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY, USAGE,
     SUITABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE WITH RESPECT TO SUCH
     ASSETS OR PROPERTIES, OR ANY PART THEREOF, OR AS TO THE WORKMANSHIP
     THEREOF, OR THE ABSENCE OF ANY DEFECTS THEREIN, WHETHER LATENT OR PATENT,
     IT BEING UNDERSTOOD THAT SUCH ASSETS AND PROPERTIES ARE BEING ACQUIRED "AS
     IS, WHERE IS" ON THE CLOSING DATE, AND IN THEIR PRESENT CONDITION, WITH ALL
     FAULTS, AND THAT BUYER SHALL RELY ON ITS OWN EXAMINATION AND INVESTIGATION
     THEREOF.


         (u)   Environmental Matters. Except as set forth on Schedule 4.1(u), to
               ---------------------
    Seller's Knowledge:

               (i)   There are no underground storage tanks, as defined in
                     Applicable Environmental Law, on the Properties or any of
                     the Operating Assets which constitute a violation of
                     Environmental Law.

               (ii)  The Operating Assets contain no friable asbestos, mercury
                     or polychlorinated biphenyls above 50 ppm or other
                     Hazardous Substances which constitute a violation of
                     Applicable Environmental Law.

               (iii) The Operating Assets have been used solely for oil and gas
                     operations and related operations. Except for the
                     production, storage and transportation of oil, gas and
                     other hydrocarbons and the storage and disposal of brine in
                     the ordinary course of business consistent with prevailing
                     oil and gas industry practices, the Operating Assets have
                     not been used to dispose of Hazardous Substances. No
                     Hazardous Substances have been disposed of that would cause
                     an adverse material impact to any of the Operating Assets.

               (iv)  There have been no spills or releases of any Hazardous
                     Substance related to the ownership or operation of the
                     Operating Assets which constitutes a violation of
                     Applicable Environmental Law, except for matters that have
                     been addressed and have no continuing adverse consequence
                     to any Seller, Subsidiary, Partnership or Starr Partnership
                     or any of the Operating Assets.

               (v)   There are no Actions pending or threatened against any
                     Partnership, Subsidiary, Starr Partnership or either Seller
                     with respect to any of the Operating Assets relating to the
                     violation of, liability under, or noncompliance with, any
                     Applicable Environmental Law; the discharge, disposal or
                     release of a Hazardous Substance; or the exposure of a
                     Person or property to a Hazardous Substance. No Seller,
                     Subsidiary, Partnership or Starr Partnership has any
                     current contingent liability in connection with the release
                     of Hazardous Substances.

               (vi)  The Operating Assets have been, and are operating, in
                     material compliance under all Applicable Environmental
                     Laws.

               (vii) Each Seller, Subsidiary, Partnership and Starr Partnership
                     has provided (or within five Business Days from the date
                     hereof will provide) Buyer all environmental audits, tests,
                     results of investigations and analyses that have been
                     performed with respect to the Operating Assets.

          (v)  Contracts. Except as set forth on Schedule 4.1(v) or Section
               ---------
     4.1(q) and in joint operating agreements entered into in the normal course
     of business, the Operating


     Assets are not subject to any instrument, agreement or other Contract
     evidencing or related to indebtedness for borrowed money. All of the
     existing Contracts between any Subsidiary, Partnership, Starr Partnership
     and/or either Seller and any of their respective Affiliates with respect to
     sales, services or support to any of the Operating Assets or operations on
     the Operating Assets shall terminate except for such Contracts otherwise
     indicated on Schedule 4.1(v) to survive Closing. Except as set forth on
     Schedule 4.1(v) and other than Consents to Assignment or Preferential
     Rights to Purchase, to Seller's Knowledge, no Contracts to which any
     Seller, Subsidiary, Partnership or Starr Partnership is a party or a
     successor-in-interest and to which Buyer will be subject after the
     Effective Time contain any provision that prevents Buyer from owning,
     managing and operating the Operating Assets in accordance with the
     Partnership's or Starr Partnerships' past practices.

          (w)  Seismic Information. At Closing, subject to the terms of the
               -------------------
     License Agreement, neither Seller nor any affiliate of Seller other than
     the Subsidiaries and the Partnership shall have any further right to any of
     the seismic data of the Subsidiaries or the Partnership which has been
     assigned or leased to the Subsidiaries, the Partnership and/or the Buyer.

          (x)  Wells. Except to the extent set forth on Schedule 4.1(x), to
               -----
     Seller's Knowledge, no well included in the Properties is subject to
     material penalties on allowables because of any overproduction or any other
     violation of Applicable Law. Except for the wells included in the
     Properties and listed in Schedule 4.1(x), there are no wells included in
     the Properties that Seller, the Subsidiaries or the E&P Partnership, or to
     Seller's Knowledge the operator of such wells, are currently obligated by
     Applicable Law, Applicable Environmental Law or order of any Governmental
     Authority to plug and abandon within a time certain or that have been shut-
     in or temporarily abandoned.

          (y)  Expenditure Obligations. Except as set forth on Schedule 9.2(f),
               -----------------------
     the Subsidiaries and the Partnership have not executed or are not otherwise
     contractually bound by any authority for expenditure with respect to any of
     the Operating Assets under any operating agreement, unit operating
     agreement, or other similar agreements that will obligate any of the
     Subsidiaries, the Partnership or Buyer to pay, after the Effective Time,
     more than $50,000 for a single project, operation or expenditure. Except as
     set forth on Schedule 9.2(f), with respect to authorizations for
     expenditure relating to any of the Operating Assets, which obligate any
     Subsidiary, Partnership or Buyer to pay more than $50,000, (i) there are no
     outstanding calls under such authorizations for expenditures for payments
     which are due or which the Subsidiaries or the Partnership have committed
     to make which have not been made; (ii) there are no material operations
     with respect to which any of the Subsidiaries and/or the Partnership has
     become a non-consenting party where the effect of such non-consent is not
     disclosed on Exhibit B, and (iii) there are no commitments for the
     expenditures of funds for drilling or other capital projects other than
     projects with respect to which the operator is not required under the
     applicable operating agreement to seek consent.

          (z)  Payout. To Seller's Knowledge, the payout balances with respect
               ------
     to any of the Properties operated by the Partnership that are subject to
     future change on account of


     reversionary interests, non-consent penalties or similar agreements or
     arrangements are set forth on Schedule 4.1(z) and are correct as of the
     dates shown on such statements.

          (aa) Absence of Certain Changes Regarding Properties. Since June 30,
               -----------------------------------------------
     1999, except as listed on Schedule 4.1(k), each Subsidiary, Partnership and
     Starr Partnership:

               (i)   has maintained and operated each of the Operating Assets
                     operated by it as a reasonably prudent operator consistent
                     with prevailing oil and gas industry practice;

               (ii)  has used reasonable efforts consistent with its past
                     practices to cause each of the Operating Assets not
                     operated by them to be maintained and operated in a good
                     and workmanlike manner and in substantially the same manner
                     as theretofore operated;

               (iii) has paid timely their share of all costs and expenses
                     attributable to the Operating Assets, except for such costs
                     and expenses that they were contesting in good faith by
                     appropriate action;

               (iv)  has performed all accounting, royalty disbursement and
                     reporting requirements, as applicable, related thereto for
                     the Production; and

               (v)   has not agreed, whether in writing or otherwise, to take
                     any action described in this Section 4.3(aa).

     (bb) Schedule 1B states all liens and mortgages that prior to the Closing
encumbered the Membership Interests, the Common Stock or the Operating Assets,
securing obligations of any Seller, Subsidiary or Partnership (other than those
items listed in clause (ii) through (ix) of the definition of "Permitted
Encumbrances"), and all of the liens and mortgages listed on Schedule 1B have
been released, insofar as they encumber the Membership Interests, the Common
Stock or the Operating Assets.

5.   Changes to Article V, Access to Information and Inspection.
     ----------------------------------------------------------

     There are no amendments to Article V of the Agreement.

6.   Changes to Article VI, Title
     ----------------------------

     There are no amendments to Article VI of the Agreement.

7.   Changes to Article VII, Environmental
     -------------------------------------

     There are no amendments to Article VII of the Agreement.

8.   Changes to Article VIII, Casualty Loss and Condemnation
     -------------------------------------------------------

     There are no amendments to Article VIII of the Agreement.


9.   Changes to Article IX, Covenants
     --------------------------------

     a.  Paragraph (f)(ii)(3) of Section 9.2 of the Agreement is hereby amended
     and restated in its entirety to read as follows:

     (3) If (A) Buyer advances any funds pursuant to subparagraph (2), and (B)
the Membership Interests are not assigned to E&P Buyer and the Common Stock is
not assigned to Pipeline Buyer at Closing, and (C) Seller does not reimburse
Buyer for all advances made by Buyer with respect to such Operating Assets
pursuant to subparagraph (2) within thirty (30) days after this Agreement
terminates, then Buyer shall own and be entitled to any right of any Partnership
that would have lapsed but for such payment, and in the case of operations,
Seller shall be entitled to receive the penalty which such Partnership, as non-
consenting party, would have suffered under the applicable operating agreement
with respect to such operations as if Buyer were a consenting party thereunder.

     b.  Section 9.4 is hereby amended and restated in its entirety to read as
follows:

               9.4    Covenants Regarding Corporate and Financial Matters.
                      ---------------------------------------------------

                      (a) Through the Closing Date, except as set forth in
          Section 9.4(b) or in Schedule 9.4 or as contemplated by this Agreement
          (including without limitation Sections 2.5 and 2.6) or otherwise
          consented to or approved by Buyer in writing, which consent or
          approval shall not be unreasonably withheld, Seller shall cause each
          Subsidiary, Partnership and Starr Partnership not to:

               (i)    Amend the Charter, Bylaws, management agreements, limited
               liability company agreements, operating agreements or other
               organizational or management documents of any the Subsidiaries or
               amend the partnership agreements of the Partnership or the Starr
               Partnerships;

               (ii)   Incur, assume or become subject to any additional
               indebtedness for money borrowed or purchase money indebtedness,
               except in the ordinary course of business and consistent with
               past practices;

               (iii)  Except as necessary to effect the transactions
               contemplated herein, declare or pay any dividend or make any
               other distribution to any shareholder of any of the Subsidiaries
               or any partner of any Partnership or Starr Partnership;

               (iv)   Redeem or otherwise acquire any shares of capital stock of
               any of the Subsidiaries or issue any capital stock, membership
               interests or other equity interests in any the Subsidiaries or
               any option, warrant or right relating thereto or any securities
               exchangeable for or convertible into any such shares;


                (v)    Permit or allow any Subsidiary's, Partnership's or Starr
                Partnership's assets or properties to be subject to any
                additional Encumbrance (other than Permitted Encumbrances) or
                sell, transfer, lease or otherwise dispose of any such assets or
                properties, other than surplus equipment not necessary for
                operations of the Business and sold for a reasonable
                consideration of less than $25,000;

                (vi)   Make any change in any method of accounting or accounting
                practice or policy, other than those required by GAAP;

                (vii)  Engage in any transactions with an Affiliate of Seller,
                other than transactions in the ordinary course and consistent
                with past practices;

                (viii) Make any changes in the method of selling natural gas,
                condensate, oil or products thereof which is not consistent with
                past practices;

                (ix)   Enter into any new derivative or Hedging Contracts with
                respect to natural gas, condensate, oil, products thereof,
                interest or any other commodities or other financial
                instruments; or

                (x)    Agree, whether in writing or otherwise, to do any of the
                foregoing.

          (b)   Prior to the Closing Date, Seller covenants to take the
     following actions to reorganize the E&P Partnership and ownership of the
     E&P Partnership:

          (i)   Contribute the limited partnership interest in the Pipeline
          Partnership owned by Tesoro Gas Resources Company, Inc. to Gathering.

          (ii)  Form Grande and Southeast as Delaware limited liability
          companies, with all Membership Interests in each being wholly owned by
          Tesoro Gas Resources Company, Inc.

          (iii) Contribute all of the capital stock of Exploration to Tesoro Gas
          Resources Company, Inc.

          (iv)  Convert Exploration and Reserves into Delaware limited liability
          companies, each of whose sole member is Tesoro Gas Resources Company,
          Inc.

          (v)   Amend the limited partnership agreement of the E&P Partnership
          to provide for establishment of series limited partnership interests,
          and approve resolutions of the partners in the E&P Partnership
          resulting in allocation of profits and losses and distributions from
          specific partnership property to specific series of limited partners,
          all initially to be held by Reserves LLC, as follows:

            (1) Series A  Properties listed on Schedule I
                ("E&P Property Package")

            (2) Series B  Properties listed on Schedule II
                ("Grande Property Package")


          (3)   Series C Properties listed on Schedule III
                ("Southeast Property Package")(vi) Dividend the Series B and
          Series C limited partnership interests in the E&P Partnership from
          Reserves LLC to Tesoro Gas Resources Company, Inc.

          (vii) Contribute the Series B limited partnership interest in the E&P
          Partnership from Tesoro Gas Resources Company, Inc. to Grande and the
          Series C limited partnership interest in the E&P Partnership from
          Tesoro Gas Resources Company, Inc. to Southeast.

     c.   Section 9.5 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

          9.5   No Solicitation of Transactions. Except as otherwise permitted
                -------------------------------
     herein, from the date of this Agreement through the Closing Date, neither
     Seller nor any of their representatives, Affiliates, directors, officers,
     employees, subsidiaries or agents will (a) solicit, consider, encourage or
     accept any other offers to acquire any of the Membership Interests or the
     Common Stock or a Subsidiary's interest or a Partnership's interest in a
     Partnership or a Starr Partnership or (b) solicit, consider, encourage or
     accept any other offers to acquire any of the assets or properties of any
     Partnership (other than as permitted by this Agreement) or (c) assist any
     third Person in preparing or soliciting such an offer. Seller shall not
     have, and shall cause such representatives, Affiliates, directors,
     officers, employees, subsidiaries and agents not to have any discussions,
     conversations, negotiations or other communication with any Person(s)
     expressing an interest in any such offer.

     d.   Paragraph (a) of Section 9.10 of the Agreement is hereby amended and
     restated in its entirety to read as follows:

          (a)   Each of Buyer and Seller, as promptly as practicable after the
     Agreement Date, shall (i) deliver, or cause to be delivered, all notices
     and make, or cause to be made, all such declarations, designations,
     registrations, filings and submissions under all statutes, laws,
     regulations and Governmental Orders applicable to it as may be required for
     it to consummate the sale of the Membership Interests and the Common Stock
     and the other transactions contemplated hereby in accordance with the terms
     of this Agreement; (ii) use commercially reasonable efforts to obtain, or
     cause to be obtained, all authorizations, approvals, orders, consents and
     waivers from all Persons necessary to consummate the foregoing; and (iii)
     use commercially reasonable efforts to take, or cause to be taken, all
     other actions necessary, proper or advisable in order for it to fulfill its
     respective obligations hereunder and to carry out the intentions of the
     parties expressed herein. The preceding sentence notwithstanding, neither
     party shall have any obligation to waive any condition herein for its
     benefit or any performance hereunder by any other party.

     e.         Section 9.12 of the Agreement is hereby amended to add a new
     subsection (c) to read as follows and to renumber existing subsection (c)
     as subsection (d):


          (c)  Seller shall reimburse Buyer for Buyer's reasonable costs and
          expenses incurred in connection with evaluating and implementing the
          like kind exchange transaction, including without limitation, legal
          and accounting fees incurred in connection with evaluating and
          implementing the like kind exchange transaction and revising this
          Agreement. Seller shall reimburse Buyer in cash for such costs and
          expenses within ten (10) days after receiving a notice from Buyer
          describing such costs and expenses in reasonable detail, and
          requesting payment.

     f.   Section 9.14 of the Agreement is hereby amended and restated in its
     entirety as follows:

          9.14  Performance of Covenants with Respect to Starr Partnerships.
                -----------------------------------------------------------
     Seller shall perform, or shall cause the Subsidiaries or the Partnership to
     perform, the covenants set forth in Sections 9.1, 9.2, 9.4, 9.5, 9.6, 9.10,
     9.11 and 9.12 with respect to the Starr Partnerships to the extent
     permitted by the Starr-County Joint Venture Agreement or the Starr-Zapata
     Partnership Agreement.

     g.   Section 9.15 of the Agreement is hereby amended and restated in its
     entirety as follows:

          9.15  Covenant and Indemnity with Respect to Cash Flow. Seller
                ------------------------------------------------
     covenants to use its best efforts to insure that after the Closing all
     cash, checks, wire transfers and other cash flow attributable to the
     Operating Assets received by Seller or any Affiliate of Seller will be
     transferred on the same day such cash flow is received by Seller or such
     Affiliate of Seller to an account designated by Buyer prior to the Closing
     (such that the transfer is recorded by the transferring bank on the same
     day such cash flow is received by Seller or an Affiliate of Seller).
     Seller agrees to indemnify and hold the Buyer Group harmless for any
     Damages asserted against, resulting to, imposed upon or incurred by the
     Buyer Group arising from any breach of this covenant.

     h.   Section 9.16 of the Agreement is hereby deleted.

     i.   Section 9.17 of the Agreement is hereby deleted.

10.  Changes to Article X, Pre-Closing Procedures.
     --------------------------------------------

     a.   Section 10.5 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

          10.5  Wire Transfer Instructions. At least two (2) Business Days
                --------------------------
     prior to the Closing Date, Seller shall provide to E&P Buyer and Pipeline
     Buyer wire transfer instructions designating a bank account and Federal
     Reserve ABA designation ID number, at a bank within the United States of
     America where the E&P Closing Settlement Price and the Pipeline Closing
     Settlement Price shall be transferred. For sales through Qualified
     Intermediaries, such accounts shall be the accounts established by the
     Qualified Intermediaries for this transaction.


     b.   A new Section 10.6 is hereby added to the Agreement as follows:

          10.6 Qualified Intermediaries. Seller may assign to Qualified
               ------------------------
     Intermediaries its rights to proceeds of the sale of the membership
     interests of Grande and Southeast as follows:

          (a)  Seller may assign to the Grande Qualified Intermediary, as a
     qualified intermediary under Section 1031 of the Code, all of Seller's
     rights in the proceeds of the sale of the membership interests in Grande,
     for the portion of the Purchase Price allocated to the Grande Property
     Package. Seller is selling and assigning to E&P Buyer all of the membership
     interests in Grande, for the portion of the Purchase Price allocated to the
     Grande Property Package, pursuant to this Agreement and, subject to Section
     21.4, an agreement in the form attached as Exhibit II to this Agreement,
     and all proceeds owed Seller for the sale of Grande will be paid to the
     Grande Qualified Intermediary.

          (b)  Seller and Reserves LLC may assign to the Southeast Qualified
     Intermediary, as a qualified intermediary under Section 1031 of the Code,
     all of Seller's rights in the proceeds of the sale of the membership
     interests in Southeast, for the portion of the Purchase Price allocated to
     the Southeast Property Package. Seller is selling and assigning to E&P
     Buyer all of the membership interests in Southeast, for the portion of the
     Purchase Price allocated to the Southeast Property Package, pursuant to
     this Agreement and, subject to Section 21.4, an agreement in the form
     attached as Exhibit III to this Agreement, and all proceeds owed Seller for
     the sale of Southeast will be paid to the Southeast Qualified Intermediary.

11.  Changes to Article XI, Closing Conditions
     -----------------------------------------

     a.   Paragraph (a) of Section 11.2 of the Agreement is hereby amended and
     restated in its entirety to read as follows:

          (a)  Representations. Except as provided otherwise in Section 9.13,
               ---------------
     the representations and warranties of Seller contained in Section 4.3
     (other than with respect to paragraphs (u), (w), (x), (y), (z) and (aa) of
     Section 4.3) shall be true and correct in all material respects on the
     Closing Date as though made on and as of that date; provided, however, that
     the accuracy of the representations and warranties in subparagraphs (k)(i),
     (ix), (x), (xi), (xii) and (xiii) of Section 4.3 shall, for purposes of
     satisfying this condition, not be affected to the extent of inaccuracies
     resulting solely from Buyer unreasonably withholding its prior written
     consent (after written request by Seller duly provided to Buyer) to the
     action taken by (or omission of) Seller, the Subsidiaries or the
     Partnership which caused such representations and warranties to be
     inaccurate.

     b.   Paragraph (c) of Section 11.2 of the Agreement is hereby amended and
     restated in its entirety to read as follows:


          (c)  Corporate Certificates and Opinion.  The Seller shall have
               ----------------------------------
     delivered to Buyer: (i) a certificate of an executive officer of each
     Seller, dated the Closing Date, certifying on behalf of such Seller that
     the representations made in Section 4.3, are true and correct as of the
     Closing Date; (ii) a certificate of incumbency for each Seller, (iii) a
     certificate of good standing for the E&P Partnership and the Pipeline
     Partnership as Delaware limited partnerships, and for each Seller and each
     of the Subsidiaries as Delaware corporations or as Delaware LLCs, as
     applicable; (iv) certified resolutions of the Boards of Directors of each
     Seller, authorizing each Seller to enter into this Agreement and the
     Transaction and to perform its obligations at Closing; and (v) an opinion
     of counsel for the Seller, acceptable to Buyer, dated the Closing Date, as
     to such matters as may reasonably be requested by Buyer and its counsel and
     are typical for transactions such as the Transaction.

          c.   The following is added as a new paragraph (k) of Section 11.2 of
               the Agreement:

     (k)  Seller shall have delivered proof, acceptable to Buyer in its
reasonable discretion, of the effectiveness of a post-effective amendment to
Seller's Registration Statement on Form S-3 (Reg. No. 333-51789), as amended,
removing any entities being transferred hereunder (including, without
limitation, Exploration, the E&P Partnership, Natural Gas and the Pipeline
Partnership) as co-registrants under such registration statement.

12.  Changes to Article XII, Closing
     -------------------------------

     a.   Section 12.1 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

          12.1 Closing.  The closing of the Transaction (the "Closing") shall
               -------
     be held on December 17, 1999 (the "Closing Date"), at 9:00 a.m. Houston
     time, at the office of Seller's counsel, 1301 McKinney, Suite 5100,
     Houston, Texas 77010, or at such other date or place as the parties may
     direct; provided, however, that if all conditions to Closing set forth in
     Article XI have not been waived or satisfied prior to December 17, 1999,
     the Closing Date shall be on the second Business Day following the waiver
     or satisfaction of such conditions.

     b.   Section 12.2 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

          12.2 Seller's Closing Obligations.  At Closing, Seller shall deliver
               ----------------------------
     to Buyer the following:

          (a)  Stock certificates representing all of the Common Stock, duly
     endorsed in blank or with separate duly executed stock powers duly endorsed
     in blank;


          (b)  The certificates representing membership interests for each of
     Reserves LLC, Exploration LLC, Grande and Southeast, respectively, duly
     endorsed in blank or with separate duly executed powers duly endorsed in
     blank;

          (c)  The stock books, stock ledgers, minute books, organizational
     documents and corporate seal for each of the Subsidiaries who are
     corporations;

          (d)  All organizational documents and books and records of Grande,
     Southeast, Reserves LLC and Exploration LLC;

          (e)  All books and records of the E&P Partnership and the Pipeline
     Partnership;

          (f)  The resignations of the officers, managers and directors of each
     of the Subsidiaries, the E&P Partnership and the Pipeline Partnership;

          (g)  Executed originals of (i) the Purchase Agreement covering the
     sale of the membership interests in Reserves LLC, (ii) the Purchase
     Agreement covering the sale of the membership interests of Grande, and
     (iii) the Purchase Agreement covering the sale of the membership interests
     of Southeast (collectively, the "LLC Purchase Agreements"), using the
     respective forms attached as Exhibit I, Exhibit II and Exhibit III to this
     Agreement;

          (h)  Instruments assigning Seller's rights under each such Purchase
     Agreement of Grande and Southeast to a respective Qualified Intermediary;

          (i)  A certificate of each Seller signed under penalties of perjury
     (i) stating that it is not a foreign corporation, foreign partnership,
     foreign trust or foreign estate, (ii) providing its U.S. Employer
     Identification Number (if applicable) and (iii) providing its address, all
     pursuant to Section 1445 of the Code.

          (j)  Such other documents or authorizations as Buyer may reasonably
     request, or as might be reasonably necessary to assign all of Seller's
     interest in the Subsidiaries, each Partnership, the Starr Partnerships and
     the Operating Assets to Buyer in accordance with the provisions hereof;

          (k)  The certificates of Seller referred to in Section 11.2(c) hereof;

          (l)  The opinion of counsel referred to in Section 11.2(c) hereof; and

          (m)  Releases, in a form acceptable to Buyer, of all liens and
     mortgages listed on Schedule 1B.

     c.   Section 12.3 is hereby amended to read as follows:

          12.3 Buyer's Closing Obligations.  At Closing, Buyer shall deliver to
               ---------------------------
     Seller the following:

          (a)  The E&P Closing Settlement Price and the Pipeline Closing
     Settlement Price, paid in immediately available funds, by wire transfer
     into the U.S. bank account designated by Seller for the Membership
     Interests and the Common Stock; proceeds for


     sale of each of Grande and Southeast shall be paid by wire transfer to the
     account designated by the Qualified Intermediary for such sale;

          (b)  The certificates of Buyer referred to in Section 11.1(c) hereof;

          (c)  The opinions of counsel referred to in Section 11.1(c) hereof;
     and

          (d)  Executed originals of the LLC Purchase Agreements using the
     respective forms attached as Exhibit I, Exhibit II and Exhibit III to the
     Agreement;

          13.  Changes to Article XIII, Adjustment Basket; Proration of Revenues
               -----------------------------------------------------------------
     and Costs
     ---------

     a.   Section 13.2 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

          (a)  Pre-Closing Settlement Statements.  The E&P Settlement Statement
               ---------------------------------
     and the Pipeline Settlement Statement are attached hereto as Exhibit IV and
     Exhibit V, respectively.

          (b)  Final Statements.
               ----------------

               (i)  As soon as practicable after the Closing Date, but in no
     event later than one hundred twenty (120) days thereafter, E&P Buyer shall
     prepare and submit to Seller a draft E&P Final Statement, which shall show
     the calculation of the adjusted E&P Final Settlement Price, as allocated to
     the E&P Property Package, the Grande Property Package and the Southeast
     Property Package, based upon the best information then available.  Such E&P
     Final Statement shall separately break out and allocate the estimated
     accounting adjustments and/or prorations of amounts attributable to the E&P
     Settlement Price, as allocated to each of the E&P Property Package, the
     Grande Property Package and the Southeast Property Package.  Seller shall
     have the right to audit such E&P Final Statement and all supporting data
     and accountings.  As soon as practicable after receipt of the E&P Final
     Statement, but in any event within thirty (30) days after receipt thereof,
     Seller shall deliver to E&P Buyer a written report containing the changes,
     if any, which Seller proposes be made to such E&P Final Statement.  If no
     response is made by Seller within such thirty (30) day period, it shall be
     presumed that Seller concurs with such E&P Final Statement, and such E&P
     Final Statement shall be the basis for the E&P Final Settlement Price.  If
     Seller submits a response, the Seller and E&P Buyer shall cooperate in good
     faith to produce not later than one hundred eighty (180) days after the
     Closing Date as accurate an E&P Final Statement as possible based upon the
     information then available.  After agreement upon an E&P Final Statement
     setting forth the E&P Final Settlement Price, the difference between such
     E&P Final Settlement Price and the E&P Closing Settlement Price paid at
     Closing shall be paid within five (5) Business Days thereafter by the Party
     owing the same.

               (ii) As soon as practicable after the Closing Date, but in no
     event later than one hundred twenty (120) days thereafter, Pipeline Buyer
     shall prepare and submit to Seller a draft Pipeline Final Statement, which
     shall show the calculation of the adjusted


     Pipeline Final Settlement Price, based upon the best information then
     available. Seller shall have the right to audit such Pipeline Final
     Statement and all supporting data and accountings. As soon as practicable
     after receipt of the Pipeline Final Statement, but in any event within
     thirty (30) days after receipt thereof, Seller shall deliver to Pipeline
     Buyer a written report containing the changes, if any, which Seller
     proposes be made to such Pipeline Final Statement. If no response is made
     by Seller within such thirty (30) day period, it shall be presumed that
     Seller concurs with such Pipeline Final Statement, and such Pipeline Final
     Statement shall be the basis for the Pipeline Final Settlement Price for
     the Common Stock. If Seller submits a response, the Seller and E&P Buyer
     shall cooperate in good faith to produce not later than one hundred eighty
     (180) days after the Closing Date as accurate a Pipeline Final Statement as
     possible based upon the information then available. After agreement upon a
     Pipeline Final Statement setting forth the Pipeline Final Settlement Price
     for the Common Stock, the difference between such Pipeline Final Settlement
     Price and the Pipeline Closing Settlement Price paid at Closing shall be
     paid within five (5) Business Days thereafter by the Party owing the same.

     b.   Section 13.3 of the Agreement is hereby amended to add the following
     paragraph (c):

          (c)  Taxes and tax prorations attributable to each of the E&P Property
     Package, the Grande Property Package, the Southeast Property Package and
     the Common Stock shall be allocated and accounted for separately, provided
     that such allocation shall not affect the total division of tax burdens and
     the total tax prorations hereunder.

14.  Changes to Article XIV, Post-Closing Procedures
     -----------------------------------------------

     There are no amendments to Article XIV to the Agreement.

15.  Changes to Article XV, Survival, Indemnities
     --------------------------------------------

     a.   Section 15.1 of the Agreement is hereby amended and restated in its
     entirety to read as follows:

          15.1 Survival.  All representations, warranties or covenants made
               --------
     herein, except for those in Sections 4.1(a), 4.1(e), 4.1(f), 4.1(g),
     4.1(i), 4.1(k), 4.1(l), 4.1(m), 4.1(n), 4.1(o), 4.1(q), 4.1(u), 4.1(v),
     4.1(w), 4.1(x), 4.1(y), 4.1(z), 4.1(aa), 4.1(bb) (with respect to Operating
     Assets only), 4.2(e), 4.2(i), 4.3(a), 4.3(e), 4.3(f), 4.3(g), 4.3(i),
     4.3(k), 4.3(l), 4.3(m), 4.3(n), 4.3(o), 4.3(q), 4.3(u), 4.3(v), 4.3(w),
     4.3(x), 4.3(y), 4.3(z), 4.3(aa), 4.3(bb) (with respect to Operating Assets
     only), Sections 5.6, 7.1, 7.2, 7.3, 7.4, 8.3, 9.1, 9.2(e), 9.9(d), 9.12(b),
     9.12(c), 9.13, 9.14 and 9.15, and Articles XV, XVI, XVII and XXI, shall
     survive for two years from the Closing Date. The covenants made in Section
     9.13 shall survive until the Parties reach agreement on the E&P Final
     Statement and the Pipeline Final Statement pursuant to Section 13.2.  The
     representations and warranties or covenants made in Sections 4.1(a),
     4.1(g), 4.1(k), 4.1(l), 4.1(m), 4.1(o), 4.1(q), 4.1(u), 4.1(v), 4.1(w),
     4.1(x), 4.1(y), 4.1(z), 4.1(aa), 4.1(bb) (with respect to


     Operating Assets only), 4.3(a), 4.3(g), 4.3(k), 4.3(l), 4.3(m), 4.3(o),
     4.3(q), 4.3(u), 4.3(v), 4.3(w), 4.3(x), 4.3(y), 4.3(z), 4.3(aa), 4.3(bb)
     and Section 9.1 shall not survive Closing and shall automatically expire
     upon Closing. The representations, releases, covenants, indemnities,
     defenses and hold harmless obligations and other obligations referenced in
     Sections 4.1(e), 4.1(f), 4.1(i), 4.1(n), 4.2(e), 4.2(i), 4.3(e), 4.3(f),
     4.3(i), 4.3(n), 5.6, 7.1, 7.2, 7.3, 7.4, 8.3, 9.2(e), 9.9(d), 9.12(b),
     9.12(c), 9.14 and 9.15 and this Article XV, and all provisions of Articles
     XVI, XVII and XXI, shall each survive Closing, and each shall continue to
     remain fully enforceable in accordance with its terms.

     b.   Section 15.2 of the Agreement is hereby amended and restated in its
     entirety as follows:

          15.2 Buyer's Indemnity.  EXCEPT AS EXPRESSLY AND SPECIFICALLY
               -----------------
     INDICATED OTHERWISE IN THIS AGREEMENT (INCLUDING WITHOUT LIMITATION
     SECTIONS 9.9(D) AND 15.3), AFTER THE CLOSING DATE, BUYER SHALL AND HEREBY
     DOES RELEASE, DEFEND, INDEMNIFY, SAVE, AND HOLD HARMLESS SELLER AND THEIR
     RESPECTIVE OFFICERS, DIRECTORS, AFFILIATES, EMPLOYEES, ATTORNEYS,
     CONTRACTORS AND AGENTS, AGAINST ANY AND ALL DAMAGES WHICH ARISE OUT OF OR
     IN CONNECTION WITH THE OWNERSHIP OF, OPERATION OF, PRODUCTION FROM OR
     ACCOUNTING BY, INCOME OF OR PAYMENTS BY THE PARTNERSHIP, THE SUBSIDIARIES
     OR THE OPERATING ASSETS, AT ANY TIME EITHER BEFORE OR AFTER THE EFFECTIVE
     TIME, OR WHICH ARISE OUT OF ANY ENVIRONMENTAL CONDITION OR OTHER HAZARDOUS
     CONDITION RELATING TO OR AFFECTING ANY OPERATING ASSET AT ANY TIME EITHER
     BEFORE OR AFTER THE EFFECTIVE TIME, INCLUDING WITHOUT LIMITATION, ALL SUCH
     COSTS, CLAIMS OR LIABILITIES ARISING OUT OF SELLER'S NEGLIGENCE OR STRICT
     LIABILITY.

     c.   Section 15.3 of the Agreement is hereby amended and restated in its
     entirety as follows:

          15.3 Seller's Indemnity.
               ------------------

          (a)  SUBJECT TO THE TERMS AND CONDITIONS OF THIS ARTICLE XV, SELLER
     SHALL INDEMNIFY, DEFEND AND HOLD HARMLESS BUYER, AND ITS PARENT OR
     SUBSIDIARY COMPANIES, PARTNERS AND OTHER AFFILIATES (INCLUDING AFTER
     CLOSING, THE SUBSIDIARIES AND THE PARTNERSHIP), AND THEIR RESPECTIVE
     OFFICERS, DIRECTORS, AFFILIATES, EMPLOYEES, ATTORNEYS, CONTRACTORS AND
     AGENTS (HEREINAFTER COLLECTIVELY REFERRED TO AS THE "BUYER GROUP"), FROM
     AND AGAINST ANY AND ALL DAMAGES ASSERTED AGAINST, RESULTING TO, IMPOSED
     UPON, OR INCURRED BY THE BUYER GROUP, DIRECTLY OR INDIRECTLY, BY



     REASON OF OR RESULTING FROM OR RELATING TO (I) ANY BREACH BY SELLER (FOR
     WHICH SELLER SHALL BE RESPONSIBLE) OF ITS SURVIVING REPRESENTATIONS,
     WARRANTIES, COVENANTS OR AGREEMENTS CONTAINED IN THIS AGREEMENT, (II) ANY
     LIABILITIES OF THE SUBSIDIARIES AND THE PARTNERSHIP WHICH ARE UNRELATED TO
     THE OPERATING ASSETS, (III) ANY LIABILITIES OF THE SUBSIDIARIES AND THE
     PARTNERSHIP FOR INCOME TAXES PRIOR TO CLOSING, AND (IV) ANY EXISTING
     LIABILITIES OF THE SUBSIDIARIES AND THE PARTNERSHIP OWED UNDER FEDERAL
     LEASES FOR PRIOR ROYALTIES RELATED TO THE PERIOD OF TIME PRIOR TO CLOSING.

          (b)  SELLER HEREBY AGREES TO AND DOES INDEMNIFY, DEFEND AND HOLD
     HARMLESS E&P BUYER AND PIPELINE BUYER FROM AND AGAINST ANY DAMAGES
     RESULTING FROM CLAIMS BY COASTAL AND/OR ITS ASSIGNS RELATING TO ANY ADVERSE
     TAX CONSEQUENCES TO COASTAL AND/OR ITS ASSIGNS ARISING AS A RESULT OF THE
     TRANSACTIONS AND/OR THE TRANSACTIONS OCCURRING PURSUANT TO THE LLC PURCHASE
     AGREEMENTS.

16.  Changes to Article XVI, Tax Matters
     -----------------------------------

     a.   Section 16.2(e) of the Agreement is amended and restated in its
     entirety as follows:

          (e)  Seller shall cause the Pipeline Partnership to make an election
     under Section 754 of the Code to adjust the basis of the assets of such
     partnerships, and shall use its reasonable efforts to cause the Starr
     Partnerships, if permitted by the applicable Charter, to make an election
     under Section 754 of the Code to adjust the basis of the assets of such
     partnerships.  Seller must amend all internal partnership agreements
     accordingly prior to the Closing Date.

     b.   Section 16.2(j) of the Agreement shall be amended and restated in its
     entirety to read as follows:

          (j)  Both Seller and Buyer will join in making a timely and effective
     election under Section 338(h)(10) of the Code (and any comparable provision
     of foreign, state or local law) with respect to the purchase by Buyer of
     the stock of Gathering hereunder (together with the elections under Section
     338(g) of the Code and any comparable provision of foreign, state or local
     law, the "Section 338(h)(10) Elections").  At the Closing, Seller and Buyer
     shall execute IRS Form 8023, completed to the extent reasonably practicable
     for Gathering.  Seller and Buyer agree to take all other action and file
     all other necessary reports to elect validly pursuant to Section 338(h)(10)
     of the Code to treat the Transaction as a sale of assets as opposed to a
     sale of the stock of Gathering.  Within 120 days after the Closing Date,
     Buyer shall deliver to Seller any additional information or required
     schedules thereto and any similar forms under applicable state or local law
     (the "Forms") with respect to Taxes relating to Buyer's purchase of the
     stock of Gathering and its interests in Pipeline.  Provided that the
     information on such Forms is, in


     the reasonable determination of Seller, correct and complete in all
     material respects, Seller will consent to the filing of such Forms. Seller
     and Buyer shall cooperate fully with each other and make available to each
     other such Tax data and other information as may be reasonably required by
     Seller or Buyer in order to prepare and timely file the Forms and any other
     required statements or schedules. With respect to the Sections 338(h)(10)
     Elections, the Modified Aggregate Deemed Sales Price as defined in Treas.
     Reg. Section 1.338(h)(10)-1 shall be allocated among the stock of Gathering
     pursuant to Treas. Reg. Section 1.338(h)(10)-1. The Buyer and the Seller
     shall use their good faith best efforts to agree upon such allocation. The
     Seller shall provide to the Buyer a schedule and supporting material
     reflecting such allocation for the Buyer's review and consent, which
     consent shall not be unreasonably withheld. The parties shall take no
     action inconsistent with, or fail to take any action necessary for the
     validity of, the Section 338(h)(10) Elections for Gathering, and shall
     adopt and utilize the asset values determined from such allocation for the
     purpose of all tax returns filed by them, and shall not voluntarily take
     any action inconsistent therewith upon examination of any tax return, in
     any refund claim, in any litigation or otherwise with respect to such tax
     returns. In the event that Buyer and Seller are unable to resolve any
     disagreements regarding the allocation of the "modified aggregate deemed
     sales price" (as defined under applicable Treasury Regulations) among the
     assets or other aspects of the Forms, Buyer (i) shall be entitled to file
     the Forms, but only if either the information not agreed upon is deleted or
     the Forms reflect that the information has not been agreed upon; or (ii) if
     acceptable to Buyer and Seller within 30 days after notice of such
     disagreement, the matter in dispute shall be resolved as soon as
     practicable by a "Big Five" independent accounting firm or, if the
     disagreement involves valuation, to a nationally recognized appraisal firm
     mutually satisfactory to the parties (but in no event longer than 30 days),
     which resolution shall be binding and conclusive upon Buyer and Seller
     without further appeal therefrom. Buyer and Seller shall bear equally the
     fees and expenses of such firm. Buyer will timely file the Forms, and any
     required supplements thereto, in the manner prescribed by Treasury
     Regulation 1.338(h)(10)-1(d) or the corresponding provisions of applicable
     foreign, state or local law, and will provide written evidence to Seller
     that it has done so. Buyer and Seller agree that neither of them will take,
     or permit any of their Affiliates to take, any action to modify or revoke
     the elections contained in or the content of any Forms without the express
     written consent of the other.


17.  Changes to Article XVII, Default and Remedies
     ---------------------------------------------

     a.   Section 17.3 of the Agreement shall be amended and restated in its
     entirety to read as follows:

          17.3 Waiver of Extraordinary Damages.  TO THE FULL EXTENT ALLOWED BY
               -------------------------------
     LAW, AND EXCEPT AS MAY BE INCLUDED IN THIRD PARTY DAMAGES SUBJECT TO ANY
     INDEMNITY OBLIGATION HEREUNDER, THE PARTIES HEREBY WAIVE AND RELEASE ANY
     RIGHTS OR CLAIMS TO PUNITIVE OR EXEMPLARY DAMAGES RESULTING FROM A BREACH
     OF THIS AGREEMENT. THE PARTIES HEREBY WAIVE THE APPLICATION OF THE TEXAS
     DECEPTIVE TRADE PRACTICES- CONSUMER PROTECTION ACT TO THE TRANSACTION.

     b.   Section 17.4 of the Agreement shall be amended and restated in its
     entirety to read as follows:

          17.4 Waiver of Jury Trial.  SELLER AND BUYER DO HEREBY IRREVOCABLY
               --------------------
     WAIVE, TO THE FULLEST EXTENT PERMITTED BY LAW, ANY AND ALL RIGHT TO A TRIAL
     BY JURY IN ANY ACTION, SUIT OR OTHER LEGAL PROCEEDING BASED UPON, ARISING
     OUT OF OR RELATING TO THIS AGREEMENT OR THE TRANSACTION.

18.  Changes to Article XVIII, Notices.
     ----------------------------------

     Section 18.1 of the Agreement is amended such that copies of notices to the
     E&P Buyer or the Pipeline Buyer shall be delivered to the following address
     instead of the address listed in the Agreement prior to this Amendment:

     Akin, Gump, Strauss, Hauer & Feld, L.L.P.
     1700 Pacific Avenue
     Suite 4100
     Dallas, Texas 75201
     Attention: Michael E. Dillard, P.C.
     Fax Number: (214) 969-4343
     Phone Number: (214) 969-2876

19.  Changes to Article XIX, Confidentiality and Disclosure.
     -------------------------------------------------------

     There are no amendments to Article XIX to the Agreement.

20.  Changes to Article XX, Termination.
     -----------------------------------

     There are no amendments to Article XX to the Agreement.


21.  Changes to Article XX, Miscellaneous.
     -------------------------------------

     a.   Section 21.1 of the Agreement shall be amended and restated to read in
     its entirety as follows:

          21.1 Entire Agreement.  This Agreement, as amended, together with the
               ----------------
     LLC Purchase Agreements, embody the entire agreement between the Parties
     (superseding all prior agreements, negotiations, representations,
     discussions, arrangements and understandings related to the subject matter
     hereof), and may be supplemented, altered, amended, modified or revoked
     only by a written instrument signed by each of the Parties; provided,
     however, the Confidentiality Agreement dated June 17, 1999, between the
     Parties shall remain effective until Closing.  If the sale of the Operating
     Assets to Buyer is not consummated, then the Confidentiality Agreement
     shall remain effective as stated therein.

     b.   Section 21.4 of the Agreement shall be amended and restated to read in
     its entirety as follows:

          21.4 Interpretation.  Words of any gender used in this Agreement
               --------------
     shall be held and construed to include any other gender, and words in the
     singular shall be held to include the plural, unless the context otherwise
     requires.  None of the terms or conditions of this Agreement, including any
     Exhibits or Schedules hereto, shall be construed for or against any Party
     hereto on the basis that such Party did or did not author the same.  All
     terms of this Agreement and the Exhibits shall be harmonized, but in the
     event of any conflict between the definition of a term in Article I and a
     more complete description or limitation of such term in a subsequent
     Article, the subsequent Article shall prevail.  The LLC Purchase Agreements
     are being executed in connection with this Agreement, and the instruments
     shall be harmonized, to the extent possible, provided however, that no
     Party shall be entitled to receive duplicate payments (including, without
     limitation, duplicate payment of any purchase price) or other relief
     regarding the same matters under both this Agreement, as amended and an LLC
     Purchase Agreement.  In the event of any conflict, redundancy or
     inconsistency between the terms of this Agreement, as amended, and an LLC
     Purchase Agreement or any other agreements or documents executed in
     connection with this Transaction (including without limitation any
     conflict, redundancy or inconsistency with respect to the provisions
     relating to indemnification, payment of purchase price, adjustments to the
     purchase price, transfer of the Common Stock or Membership Interests,
     representations, warranties and covenants), the provisions of this
     Agreement, as amended, shall control and prevail.  The Article and Section
     headings are for convenience only and shall have no significance in the
     interpretation hereof.

     c.   Section 21.9 of the Agreement shall be amended and restated in its
     entirety as follows:

          21.9 Binding Effect, Assignment.  All the terms, provisions,
               --------------------------
     covenants, representations, warranties and conditions of this Agreement
     shall be binding upon and inure to the benefit of and be enforceable by the
     Parties and, except as otherwise


     prohibited, their respective successors; however, this Agreement and the
     rights and obligations hereunder shall not be assignable or delegable by
     any Party without the express written consent of the non-assigning or non-
     delegating Parties, which consent may be withheld for any or no reason;
     provided that Buyer may assign some or all its rights, duties and
     obligations under this Agreement to an Affiliate of EEX Corporation. Any
     assignment or delegation requiring consent which is made without such
     consent will be void.

     d.   Section 21.15 of the Agreement shall be amended by adding the
     following as a new sentence at the end thereof:

     If E&P Buyer and Pipeline Buyer are different Persons as a result of a
     permitted assignment of the rights and obligations of either E&P Buyer or
     Pipeline Buyer hereunder, E&P Buyer and Pipeline Buyer shall be jointly and
     severally liable for all of the duties and obligations of E&P Buyer and
     Pipeline Buyer hereunder.

     e.   Section 21.17 of the Agreement shall be amended and restated in its
     entirety as follows:

          21.17   EEX Corporation Guarantee.  EEX Corporation (a) agrees to be
                  -------------------------
     jointly and severally liable with E&P Buyer and Pipeline Buyer for all of
     E&P Buyer's and Pipeline Buyer's payment obligations under this Agreement
     and (b) irrevocably and unconditionally guarantees the performance by E&P
     Buyer and Pipeline Buyer of their respective indemnity obligations under
     Article XV.

22.  Addition of Exhibits and Schedules.
     -----------------------------------

     The Agreement is amended to add the following exhibits and schedules to the
Agreement, each of which is attached to this Amendment:

     Exhibit B-1  Pipeline Properties
     Exhibit C-1  Pipeline Balance Sheet
     Exhibit I    Reserves LLC Purchase Agreement
     Exhibit II   Grande LLC Purchase Agreement
     Exhibit III  Southeast LLC Purchase Agreement
     Exhibit IV   E&P Settlement Statement
     Exhibit V    Pipeline Settlement Statement
     Schedule I   E&P Property Package
     Schedule II  Grande Property Package
     Schedule III Southeast Property Package


23.  General Amendment Provisions.
     -----------------------------

     The parties hereto acknowledge that the terms of the Agreement, as amended
by this Amendment, shall continue in full force and effect.  This Amendment
shall be governed and construed and enforced in accordance with the laws of the
State of Texas, without giving effect to principles of conflict of laws.  This
Amendment may be executed in any number of counterparts, and each and every
counterpart shall be deemed for all purposes one agreement.


     IN WITNESS WHEREOF, the parties have caused this Amendment to be executed
by their duly authorized officers as of the date first above written.

SELLER                                  BUYER
- ------                                  -----

  TESORO PETROLEUM                           EEX OPERATING LLC
  CORPORATION

                                             By:  EEX CORPORATION

  By:________________________________        By:______________________________
  Name:______________________________        Name:____________________________
  Title:_____________________________        Title:___________________________


  TESORO GAS RESOURCES                       EEX CORPORATION, for purposes of
  COMPANY, INC.                              Section 21.17

  By:________________________________        By:______________________________
  Name:______________________________        Name:____________________________
  Title:_____________________________        Title:___________________________