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                                                                     EXHIBIT 2.2

                   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:



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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).

     "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.


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     "GRANDE" shall mean Tesoro Grande 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.

     "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).

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     "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 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, 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.


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     "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:

     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

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     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.

     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 existing subparagraphs (vi) and (vii) of Section 2.4(a) are
         renumbered (vii) and (viii), respectively, and a new subparagraph (vi)
         is added as follows:

         (vi)  All the rights, title and interests of Seller and the Partnership
               in and to the Bob West Field compression facility and the Bob
               West Field amine plant;

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

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         (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.

     g.  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:

     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

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             (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;


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         (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

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               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."

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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.

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     (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, or (C)
               cause the recognition of gain for which the Buyer (or, after the
               Closing, the Subsidiaries) will be responsible for the tax
               thereon or subject any Subsidiary or its assets to any Tax other
               than Tax for which Seller is responsible under Article XVI.

         (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

                                       12

   13


               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

                                       13

   14


               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


                                       14

   15
                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


                                       15

   16
     (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
                                       16

   17


                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 (representing a 99% interest in all of the capital and
                assets associated with Series A) is held by Reserves LLC, the
                entire Series B limited partnership interest (representing a
                100% interest in all of the capital and assets associated with
                Series B) is held by Grande and the entire Series C limited
                partnership interest (representing a 100% interest in all of the
                capital and assets associated with Series C) is held by
                Southeast. Exploration LLC is the general partner of the E&P
                Partnership (representing a 1% interest in all of the capital
                and assets of Series A). 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, Southeast or Exploration LLC 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,

                                       17

   18


                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

                                       18

   19


                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

                                       19

   20


                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

                                       20

   21

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.


                                       21

   22



         (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






                                       22

   23
                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), or with Buyer's prior written consent,
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;

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         (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.


                                       24

   25


         (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

                                       25

   26


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
                                       26

   27


                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

                                       27

   28


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.

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   29



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;

                                       29

   30



             (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.

                                       30

   31



        (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)   Transfer the Series B limited partnership interest in the E&P
        Partnership from Reserves LLC to Grande and transfer the Series C
        limited partnership interest in the E&P Partnership from Reserves LLC 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
                                       31

   32


     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.

                                       32

   33

     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 or
     before the next Business Day after 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 or
     before the next Business Day after such cash flow is received by Seller or
     an Affiliate of Seller). To the extent Seller does not make the transfer
     required by this Section 9.15 on or before the next Business Day after
     receipt of such cash flow, Seller agrees to pay to Buyer (a) interest at
     the prime rate of Buyer's primary lender (accruing from the second Business
     Day after receipt by Seller of such cash flow) on any such cash flow
     remaining outstanding for the second and third Business Day after receiving
     such funds and (b) the maximum interest allowable by Applicable Law on any
     such cash flow remaining outstanding thereafter. 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
     failure by Seller to transfer any amounts that, together with any other
     amounts not transferred pursuant to this Section 9.15, aggregate greater
     than $1 million and that Seller has not transferred within one Business Day
     after written notice by Buyer is received by Seller. Buyer and Seller agree
     to cooperate in identifying amounts that may need to be transferred by
     Seller to Buyer under this Section 9.15.

     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.



                                       33
   34

     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



                                       34
   35

     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;



                                       35
   36

        (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



                                       36
   37

     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




                                       37
   38

     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,




                                       38
   39

     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.



                                       39
   40

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




                                       40
   41

     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.





                                       41
   42

18.  CHANGES TO ARTICLE XVIII, NOTICES.

     a. Section 18.1 of the Agreement is amended such that notices to Seller
     shall be delivered to the following address instead of the address listed
     in the Agreement prior to this Amendment:

     Tesoro Petroleum Company
     300 Concord Plaza Drive
     San Antonio, Texas 78216-6999
     Attention: James C. Reed, Jr.
     Fax Number:   (210) 283-2400
     Phone Number: (210) 828-8484

     b. 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.



                                       42
   43

        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 or any provisions of the exhibits or schedules), 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.



                                       43
   44

     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.


                                       44
   45

     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 CORPORATION              EEX OPERATING LLC

                                              BY:  EEX CORPORATION

    By: /s/ SHARON L. LAYMAN                  By: /s/ RICHARD S. LANGDON
        --------------------------------          ------------------------------

    Name: Sharon L. Layman                    Name: Richard S. Langdon
          ------------------------------            ----------------------------

    Title: Vice President and Treasurer       Title: EVP & CFO
           -----------------------------             ---------------------------


    TESORO GAS RESOURCES COMPANY, INC.    EEX CORPORATION, FOR PURPOSES OF
                                          SECTION 21.17

    By: /s/ JEFFREY B. FABIAN             By: /s/ RICHARD S. LANGDON
        --------------------------------      ----------------------------------

    Name: Jeffrey B. Fabian               Name: Richard S. Langdon
          ------------------------------        --------------------------------

    Title: President                      Title: EVP & CFO
           -----------------------------         -------------------------------


   46


The exhibits and schedules listed in Section 22 of the First Amendment to Stock
Purchase Agreement have been omitted. The Registrant will furnish a copy of any
omitted exhibits and schedules to the Securities and Exchange Commission upon
request.