1
                                                                    EXHIBIT 10.1





                          MASTER TRANSACTION AGREEMENT

                                    BETWEEN

                            EQUISTAR CHEMICALS, LP,

                              OCCIDENTAL PETROLEUM
                                  CORPORATION,

                         LYONDELL PETROCHEMICAL COMPANY

                                      AND

                           MILLENNIUM CHEMICALS INC.
   2
                               TABLE OF CONTENTS



                                                                                                           PAGE
                                                                                                       
SECTION 1         RELATED AGREEMENTS AND CLOSING  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.1         Tier 1 Related Agreements   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.2         Tier 2 Related Agreements   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.3         Closing Date  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.4         Partnership Long-term Debt  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2
      1.5         Closing Transactions  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2

SECTION 2         REPRESENTATIONS AND WARRANTIES  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3
      2.1         Representations and Warranties of the Partnership   . . . . . . . . . . . . . . . . . . .  3
      2.2         Representations and Warranties of Occidental  . . . . . . . . . . . . . . . . . . . . . .  8
      2.3         Representations and Warranties of Lyondell  . . . . . . . . . . . . . . . . . . . . . . .  11
      2.4         Representations and Warranties of Millennium  . . . . . . . . . . . . . . . . . . . . . .  13

SECTION 3         ADDITIONAL AGREEMENTS   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  15
      3.1         Access to Information   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  15
      3.2         Conduct of the Occidental Subject Business Pending the Closing Date   . . . . . . . . . .  15
      3.3         Conduct of the Partnership Subject Business Pending the Closing Date  . . . . . . . . . .  17
      3.4         Further Actions   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  18
      3.5         Notifications   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  20
      3.6         Employee Matters  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  20
      3.7         Partnership Unanimous Consent Items   . . . . . . . . . . . . . . . . . . . . . . . . . .  20

SECTION 4         CONDITIONS TO CLOSING   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21
      4.1         Conditions Precedent to Obligations of All Parties  . . . . . . . . . . . . . . . . . . .  21
                  (a)     No Injunction, etc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21
                  (b)     Tier 2 Related Agreements . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21
                  (c)     Government Licenses and Consents  . . . . . . . . . . . . . . . . . . . . . . . .  21
                  (d)     HSR Act . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21
      4.2         Conditions Precedent to Obligations of the Partnership  . . . . . . . . . . . . . . . . .  21
                  (a)     Accuracy of Representations and Warranties  . . . . . . . . . . . . . . . . . . .  22
                  (b)     Performance of Agreements . . . . . . . . . . . . . . . . . . . . . . . . . . . .  22
                  (c)     No Material Adverse Change  . . . . . . . . . . . . . . . . . . . . . . . . . . .  22
                  (d)     Officer's Certificates  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  22
      4.3         Conditions Precedent to Obligations of Occidental   . . . . . . . . . . . . . . . . . . .  22
                  (a)     Accuracy of Representations and Warranties  . . . . . . . . . . . . . . . . . . .  22
                  (b)     Performance of Agreements . . . . . . . . . . . . . . . . . . . . . . . . . . . .  22
                  (c)     No Material Adverse Change  . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
                  (d)     Board of Directors Approval . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
                  (e)     Officer's Certificates  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
                  (f)     Third Party Consents  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23






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SECTION 5         TERMINATION AND WAIVER  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
      5.1         General   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
      5.2         Effect of Termination   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  24

SECTION 6         MISCELLANEOUS   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  24
      6.1         Successors and Assigns  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  24
      6.2         Benefits of Agreement Restricted to Parties   . . . . . . . . . . . . . . . . . . . . . .  24
      6.3         Notices   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  24
      6.4         Severability  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  25
      6.5         Press Releases  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  25
      6.6         Confidentiality Agreement   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
      6.7         Construction  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
      6.8         Counterparts  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
      6.9         Governing Law   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
      6.10        Transaction Costs   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
      6.11        Amendment   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  27
      6.12        Jurisdiction; Consent to Service of Process; Waiver   . . . . . . . . . . . . . . . . . .  27
      6.13        Waiver of Jury Trial  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  28
      6.14        Action by the Partnership   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  28


APPENDICES

Appendix A        Definitions
Appendix B        List of Related Agreements

SCHEDULES

Schedule 2.1       Exceptions to Representations and Warranties of the 
                   Partnership
Schedule 2.2       Exceptions to Representations and Warranties of Occidental
Schedule 2.3       Exceptions to Representations and Warranties of Lyondell
Schedule 2.4       Exceptions to Representations and Warranties of Millennium
Schedule 4.3(f)    Occidental Consents
Schedule 6.10      Certain Expenses





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EXHIBITS

Exhibit A         Form of Amended and Restated Agreement of Limited Partnership
Exhibit B         Form of Occidental Contribution Agreement
Exhibit C         Form of Amended and Restated Parent Agreement
Exhibit D         Form of Sales Agreement (Ethylene)





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   5
                          MASTER TRANSACTION AGREEMENT


      This Master Transaction Agreement (this "Agreement") dated May 15, 1998
is entered into by and among Equistar Chemicals, LP, a Delaware limited
partnership (the "Partnership"), Occidental Petroleum Corporation, a Delaware
corporation ("Occidental"), Lyondell Petrochemical Company, a Delaware
corporation ("Lyondell"), and Millennium Chemicals Inc., a Delaware corporation
("Millennium").

      The definitions of capitalized terms used in this Agreement, including
the appendices hereto, are set forth in Appendix A hereto.

      WHEREAS, Lyondell and Millennium entered into the Master Transaction
Agreement dated July 25, 1997, as amended, which contemplated, among other
things, the formation of the Partnership;

      WHEREAS, the Initial Partners entered into the Limited Partnership
Agreement of the Partnership dated October 10, 1997 and the Certificate of
Limited Partnership with respect to the Partnership became effective October
17, 1997;

      WHEREAS, the Partnership commenced operations December 1, 1997 upon its
acquisition of the Subject Businesses of Lyondell and Millennium Petrochemicals
Inc., a Virginia corporation and an indirect wholly owned subsidiary of
Millennium ("Millennium Petrochemicals");

      WHEREAS, Lyondell and Millennium, the respective ultimate parent entities
of the Initial Partners, desire to admit to the Partnership (i) PDG Chemical
Inc., a Delaware corporation and an indirect, wholly owned subsidiary of
Occidental ("PDG Chemical"), as a general partner, and (ii) Occidental
Petrochem Partner 1, Inc., a Delaware corporation and a wholly owned Subsidiary
("OCC Sub") of Occidental Chemical Corporation, a New York corporation ("OCC"),
and Occidental Petrochem Partner 2, Inc., a Delaware corporation and a wholly
owned Subsidiary ("Oxy CH Sub") of Oxy CH Corporation, a California corporation
("Oxy CH"), as limited partners, upon the transfer to the Partnership of the
Subject Business to be contributed by the Occidental Partners, each a wholly
owned Subsidiary of Occidental;

      WHEREAS, upon the terms and subject to the conditions set forth herein,
the Occidental Partners will contribute their Subject Business to the
Partnership through a merger, a partnership interest transfer and certain asset
transfers, the Partnership will issue Units to the Occidental Partners and the
Occidental Partners will become partners in the Partnership, and certain other
agreements will be entered into as provided for herein; and

      WHEREAS, the Parties have made all applicable filings under the HSR Act
with respect to the transactions contemplated hereby and have received
confirmation from the Federal Trade Commission of the early termination of the
applicable waiting period under the HSR Act;





   6
      WHEREAS, the parties who have executed this Agreement (the "Parties") wish
to make certain representations and warranties to one another and provide for
the coordination of the closing of all the transactions contemplated by this
Agreement (the "Closing");

      NOW, THEREFORE, in consideration of the premises and the mutual covenants
of the Parties set forth herein, it is hereby agreed as follows:

                                   SECTION 1
                         RELATED AGREEMENTS AND CLOSING

      1.1         Tier 1 Related Agreements.  The Tier 1 Related Agreements are
designated as such on Appendix B.  Forms of each of the Tier 1 Related
Agreements (including forms of certain of the exhibits and versions of certain
of the schedules thereto current as of the dates indicated therein) are
attached as Exhibits to this Agreement.  On the terms and subject to the
conditions set forth herein, the Parties shall cause each such agreement to be
executed and delivered by the appropriate parties thereto at the Closing in
substantially the form attached hereto with such changes as may be agreed to by
the Parties in good faith.

      1.2         Tier 2 Related Agreements.  The Tier 2 Related Agreements are
designated as such on Appendix B.  The forms of each of the Tier 2 Related
Agreements shall be negotiated by the Parties prior to the Closing in good
faith.  On the terms and subject to the conditions set forth herein, the
Parties shall cause such agreements to be executed and delivered in such forms
by the appropriate parties thereto at the Closing.

      1.3         Closing Date.  Provided that the conditions precedent set
forth in Section 4 of this Agreement shall have been satisfied or waived, the
Closing shall be held at a mutually agreeable location on the date hereof or on
such other date as may be agreed to in writing by the Parties (the "Closing
Date").  The Closing shall be deemed to occur at 4:00 a.m. Houston, Texas time
on the Closing Date.

      1.4         Partnership Long-term Debt.  At or immediately subsequent to
the Closing Date, the Partnership's long-term debt shall consist of:  (i)
borrowings under a bank credit agreement or agreements providing for maximum
borrowings in the amount of $1.25 billion (inclusive of any amounts to be used
for working capital purposes); (ii) Lyondell Assumed Debt (as defined in the
Initial Master Transaction Agreement) in the amount of $745 million and (iii)
Occidental Assumed Debt in the amount of $205 million; provided, however, that
the amount of the credit agreement or agreements described in (i) above may be
adjusted to such greater amount as may be reasonably satisfactory to the
Partnership and Occidental.

      1.5         Closing Transactions.  As contemplated by this Agreement and
by the Occidental Contribution Agreement and the Amended and Restated
Partnership Agreement, as applicable, on the Closing Date:





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   7
                  (a)     OCC will contribute or cause to be contributed
      certain assets to OCC Sub which will simultaneously contribute  such
      assets to the Partnership, subject to the assumption by the Partnership
      of certain liabilities;

                  (b)     OCC Sub will assign a lease for certain assets to the
      Partnership;

                  (c)     Oxy CH will contribute all of the issued and
      outstanding capital stock of Oxy Petrochemicals to Oxy CH Sub;

                  (d)     Oxy Petrochemicals Inc., a wholly owned direct
      Subsidiary of Oxy CH Sub ("Oxy Petrochemicals") and the Partnership will
      merge, with the Partnership as the surviving entity;

                  (e)     PDG Chemical will contribute or cause to be
      contributed certain assets to the Partnership, subject to the assumption
      by the Partnership of certain liabilities;

                  (f)     the Partnership will (i) issue Units to the
      Occidental Partners (pursuant to asset contributions, partnership
      interest transfer or the merger, as the case may be) and the Occidental
      Partners will be admitted as partners of the Partnership and (ii) issue
      Units to Lyondell LP, Lyondell GP, Millennium LP and Millennium GP;

                  (g)     OCC will agree to guarantee (with the form and terms
      thereof to be substantially in the form attached to that certain letter
      agreement, of even date, by and between OCC and the Partnership)
      $419,700,000 of indebtedness of the Partnership; and

                  (h)     the Partnership shall deliver (i) a note to Oxy CH
      Sub obligating the Partnership to pay $419,700,000 plus interest in
      accordance with the terms described therein and (ii) a note to Millennium
      LP obligating the Partnership to pay $75 million plus interest in
      accordance with the terms described therein.


                                   SECTION 2
                         REPRESENTATIONS AND WARRANTIES

      2.1         Representations and Warranties of the Partnership.  Except as
set forth on Schedule 2.1, the Partnership represents and warrants to each
other Party as follows:

                  (a)     Organization, Good Standing and Power.  The
      Partnership (i) is a limited partnership duly organized, validly existing
      and in good standing under the laws of the state of Delaware and has the
      power and authority under its constituent documents to own, lease and
      operate its assets and to conduct its Subject Business now being
      conducted by it, (ii) is duly authorized, qualified or licensed to do
      business as a foreign limited partnership in, and is in good standing in,
      each of the jurisdictions in which its right, title or interest in or to
      any of the assets held by it requires such authorization, qualification
      or licensing, except where the failure to be so authorized, qualified,
      licensed or in good standing would not be reasonably





                                      -3-
   8
      likely to have a Material Adverse Effect with respect to its Subject
      Business, and (iii) has, and in the case of the Related Agreements to be
      executed by it at or prior to the Closing, will have, all requisite
      corporate power and authority, or power and authority under its
      constituent documents, to enter into this Agreement and, as applicable,
      the Related Agreements to which it is or will be a party and to perform
      its obligations hereunder and thereunder.

                  (b)     Authorization and Validity of Agreements.

                          (i)     The execution, delivery and performance by
                  the Partnership of this Agreement and the consummation by it
                  of the transactions contemplated hereby have been duly
                  authorized and approved by all necessary corporate or similar
                  action on its part.  This Agreement has been duly and validly
                  executed and delivered by the Partnership and is its legal,
                  valid and binding obligation, enforceable against it in
                  accordance with its terms, except as the same may be limited
                  by applicable bankruptcy, insolvency, reorganization,
                  moratorium or other laws related to or affecting creditors'
                  rights generally and by general equity principles.

                          (ii)    The execution, delivery and performance by
                  the Partnership of the Related Agreements to which it will be
                  a party and the consummation by it of the transactions
                  contemplated thereby will be, as of the Closing, duly
                  authorized and approved by all necessary action on its part.
                  At the Closing, each of the Related Agreements to which the
                  Partnership will be a party will be duly and validly executed
                  and delivered by the Partnership and will be upon execution
                  and delivery a legal, valid and binding obligation,
                  enforceable against it in accordance with its terms, except
                  as the same may be limited by applicable bankruptcy,
                  insolvency, reorganization, moratorium or other laws related
                  to or affecting creditors' rights generally and by general
                  equity principles.

                  (c)     Lack of Conflicts.   Except with respect to the HSR
      Act as set forth in Section 4.1(d), each of the execution, delivery and
      performance by the Partnership of this Agreement and the Related
      Agreements to which it is or will be a party and the consummation by it
      of the transactions contemplated hereby and thereby does not and, as of
      the Closing, will not (i) violate (with or without the giving of notice
      or the lapse of time or both) any Legal Requirement applicable to it or
      its Subsidiaries, other than those that would not be reasonably likely to
      have a Material Adverse Effect with respect to its Subject Business, (ii)
      conflict with, or result in the breach of, any provision of the charter
      or by-laws or similar governing or organizational documents of it or its
      Subsidiaries, (iii) result in the creation of any Encumbrance upon any of
      their assets, other than those contemplated by this Agreement or any of
      the Related Agreements, or those that would not be reasonably likely to
      have a Material Adverse Effect with respect to its Subject Business, or
      (iv) violate, conflict with or result in the breach or termination of or
      otherwise give any other Person the right to terminate, or constitute a
      default, event of default or an event which with notice, lapse of time or
      both, would constitute a default or event of default under the terms of,
      any contract, indenture, lease, mortgage, Government License or other
      agreement or instrument to which it or any of its Subsidiaries is a party
      or by which the properties or businesses of it or any of





                                      -4-
   9
      its Subsidiaries are bound, except for violations, conflicts, breaches,
      terminations and defaults that would not be reasonably likely to have a
      Material Adverse Effect with respect to its Subject Business.

                  (d)     Certain Fees.  Neither the Partnership nor any of its
      Affiliates nor any of its officers, directors or employees, on behalf of
      it or such Affiliates, has employed any broker or finder or incurred any
      other liability for any financial advisory fees, brokerage fees,
      commissions or finders' fees in connection with the transactions
      contemplated hereby.

                  (e)     Financial Statements.  The Partnership's audited
      financial statements as of and for the year ended December 31, 1997 and
      any unaudited quarterly financial statements prepared pursuant to Section
      5.4 of the Partnership Agreement since December 31, 1997 (in each case
      including any notes thereto), were prepared in accordance with United
      States generally accepted accounting principles applied on a consistent
      basis ("GAAP") throughout the periods indicated (except as may be
      indicated in the notes thereto and except that unaudited or quarterly
      financial statements do not contain all GAAP notes to such financial
      statements) and each fairly presents the consolidated (or combined, as
      applicable) financial position, results of operations and changes in
      partners' equity and cash flows of the Partnership and its subsidiaries
      as at the respective dates thereof and for the respective periods
      indicated therein (subject, in the case of unaudited statements, to
      normal and recurring year-end adjustments).

                  (f)     Absence of Certain Changes.  Since December 31, 1997,
      (i) the Partnership and its Affiliates have not incurred any material
      liabilities or obligations, fixed, contingent, accrued or otherwise, (A)
      that relate to or are allocable to its Subject Business and that have had
      or are reasonably likely to have a Material Adverse Effect with respect
      to its Subject Business, or (B) that would cause the long-term debt of
      the Partnership immediately prior to the Closing to exceed the aggregate
      of $1.745 billion and any amounts borrowed under the Partnership's bank
      credit facility for working capital, (ii) the Partnership and its
      Affiliates have conducted its Subject Business in all material respects
      in the ordinary course, and (iii) no event, occurrence or other matter
      has occurred that is reasonably likely to have a Material Adverse Effect
      with respect to its Subject Business, provided that this determination
      shall be made without regard to any change in general economic or
      political conditions or any change in raw materials prices, product
      prices, industry capacity or other matter of industry-wide application
      that affects its Subject Business and Occidental's Subject Business in a
      substantially similar way.

                  (g)     Partnership Documents.  The Partnership has provided
      to Occidental a true and correct copy of the Partnership Agreement, as
      amended to date.  The Partnership has provided to Occidental true and
      correct copies of (i) all minutes of meetings of the Partnership
      Governance Committee held to date and such minutes accurately reflect all
      actions, approvals and authorizations (including with respect to the
      Strategic Plan) by or of the Partnership Governance Committee, (ii) the
      Strategic Plan and (iii) the current annual budget of the Partnership.





                                      -5-
   10
                  (h)     Partnership Interests.  Without giving effect to this
      Agreement or the transactions contemplated hereby, Lyondell LP, Lyondell
      GP, Millennium LP and Millennium GP are the only Partners in the
      Partnership and the only holders of Units, in the denominations set forth
      in the Partnership Agreement.  Without giving effect to this Agreement or
      the transactions contemplated hereby, there are no outstanding
      subscriptions, options, convertible securities, warrants or calls of any
      kind issued or granted by, or binding upon, the Partnership to purchase
      or otherwise acquire or to sell or otherwise dispose of any security of
      or equity interest in the Partnership.

                  (i)     Conduct of the Partnership Subject Business since
      December 1, 1997.  Except as required or contemplated by approvals or
      authorizations (including the Strategic Plan) by or of the Partnership
      Governance Committee, since the contribution of their Subject Assets to
      the Partnership by Lyondell and Millennium on December 1, 1997, the
      Partnership has:

                  (i)     maintained its books, accounts and records relating
                          to its Subject Business in the usual, regular and
                          ordinary manner, complied in all material respects
                          with all Legal Requirements and contractual
                          obligations applicable to its Subject Business or to
                          the conduct of its Subject Business and performed all
                          of its material obligations relating to its Subject
                          Business;

                  (ii)    not (A) modified or changed in any material respect
                          any of its assets or disposed of any material asset
                          except for (1) inventory, equipment, supplies and
                          other assets sold or otherwise disposed of in the
                          ordinary course of business and (2) any assets that
                          in the ordinary course of business were replaced with
                          substantially similar assets, (B) except in the
                          ordinary course of business, (x) entered into any
                          contract, commitment or agreement material to the
                          operation of its Subject Business or use of its
                          assets or, except as expressly contemplated by or
                          required pursuant to their respective terms, modified
                          or changed in any material respect any obligation
                          under any such contract, commitment or agreement, (y)
                          modified or changed in any material respect any
                          obligation under its Government Licenses, (z)
                          modified or changed in any material respect the
                          manner in which the products produced by its Subject
                          Business are marketed and sold, or (C) entered into
                          interest rate protection or other hedging agreements
                          (except for hydrocarbon hedging agreements entered
                          into in the ordinary course and expiring prior to
                          December 31, 1998) relating to its Subject Business;
                          provided, that, for purposes of (A) and (B),
                          "material" shall mean a change or modification that
                          was subject to the unanimous voting requirement of
                          Section 6.7 of the Partnership Agreement; and

                  (iii)   not waived any material claims or rights relating to
                          its Subject Business.

                  (j)     Employee Benefits.





                                      -6-
   11
                  (i)     Each of the Partnership's Defined Benefit and Defined
                          Contribution Pension Plans covering employees
                          ("Employee Plan") is in substantial compliance with
                          applicable requirements prescribed by any and all
                          Legal Requirements, including, but not limited to the
                          Code, except for violations the occurrence of which
                          would not in the aggregate reasonably be expected to
                          have a Material Adverse Effect with respect to its
                          Subject Business;

                  (ii)    The Partnership has in all material respects
                          performed all obligations required to be performed by
                          it under ERISA, the Code and any other applicable
                          Legal Requirements and under the terms of each
                          Employee Plan, except such failures to perform which
                          would not in the aggregate reasonably be expected to
                          have a Material Adverse Effect with respect to its
                          Subject Business.  The Partnership has received no
                          written notice of the existence of any material
                          default or violation by any other party of any of
                          such Legal Requirements, terms or requirements
                          applicable to any of the Employee Plans;

                  (iii)   Other than routine claims for benefits, the
                          Partnership has not received any written notice of
                          any pending material claims or lawsuits which have
                          been asserted or instituted against any of the
                          Employee Plans, the assets of the trust or funds
                          under the Employee Plans, the sponsor or
                          administrator of any of the Employee Plans, or
                          against any fiduciary of any of the Employee Plans
                          with respect to the operation of such Plan;

                  (iv)    The Partnership has not received any written notice
                          of any pending investigation or pending enforcement
                          action by the Pension Benefit Guaranty Corporation,
                          the Department of Labor, the Internal Revenue Service
                          or any other Authority with respect to any of the
                          Employee Plans;

                  (v)     All contributions required to be made under the terms
                          of the Partnership's Employee Plans have been timely
                          made.  No Employee Plan has an "accumulated funding
                          deficiency" (within the meaning of Section 412 of the
                          Code or Section 302 of ERISA);

                  (vi)    All of the Partnership's "group health plans" (within
                          the meaning of Code Section 5000(b)(1)) have been
                          operated in substantial compliance with the group
                          health plan continuation coverage requirements of
                          Section 4980B of the Code and Sections 601 through
                          608 of ERISA, Title XXII of the Public Health Service
                          Act and the provisions of the Social Security Act;

                  (vii)   There has been no act or omission by the Partnership
                          that has given rise to or may give rise to material
                          fines, penalties, taxes, or related charges under
                          Section 502(c), (i) or (l) or Section 4071 of ERISA
                          or Chapter 43 of the Code or the imposition of a lien
                          pursuant to Sections 401(a)(29) or 412(n) of the Code
                          or pursuant to ERISA;





                                      -7-
   12
                  (viii)  Except with respect to the transactions contemplated
                          by this Agreement, no "reportable event" within the
                          meaning of Section 4043 of ERISA, or prohibited
                          transaction within the meaning of Section 406 of
                          ERISA, has occurred with respect to any Employee Plan
                          which would reasonably be expected to have a Material
                          Adverse Effect; and

                  (ix)    No Employee Plan is a "multiemployer plan" as such
                          term is defined in section 3(37) of ERISA.  No
                          Employee Plan is a plan maintained by more than one
                          employer (a so-called "multiple employer plan") for
                          purposes of section 413(c) of the Code or otherwise.

                  (k)     Conduct of Business in Compliance with Regulatory and
      Contractual Requirements.  The Partnership and each Affiliate thereof is
      operating and conducting its Subject Business in compliance with all
      applicable Legal Requirements, rights of concession, licenses, know-how
      or other proprietary rights of others, the failure to comply with which
      would reasonably be expected to have a Material Adverse Effect with
      respect to its Subject Business.

                  (l)     Legal Proceedings.  There is no litigation,
      proceeding, claim, grievance, arbitration, investigation or other action
      to which the Partnership or any Affiliate thereof is a party (including
      proceedings or claims by or before the National Labor Relations Board,
      the Equal Employment Opportunity Commission, the Department of Labor or
      any other Authority) (i) that is pending or, to the Knowledge of the
      Partnership, threatened, (ii) that relates in any way to the operation or
      conduct of its Subject Business, or to the transactions contemplated by
      this Agreement, and (iii) that upon resolution adverse to Partnership or
      any Affiliate, could reasonably be expected to have a Material Adverse
      Effect with respect to its Subject Business.

                  (m)     Initial Asset Contributions.  To the Partnership's
      Knowledge, there is no basis for a claim by the Partnership against
      Lyondell or Millennium Petrochemicals for breach of representation or
      warranty of any of their respective representations and warranties set
      forth in the Lyondell Asset Contribution Agreement or the Millennium
      Asset Contribution Agreement.

      2.2         Representations and Warranties of Occidental.   Except as set
forth on Schedule 2.2, Occidental represents and warrants to each other Party
as follows:

                  (a)     Organization, Good Standing and Power.  Occidental
      and each member of its Group (i) is a corporation, duly organized,
      validly existing and in good standing under the laws of the jurisdiction
      of its incorporation and has the corporate power and authority to own,
      lease and operate its assets and, if applicable, to conduct the Subject
      Business now being conducted by it and to be conducted by it as of the
      Closing, (ii) is duly authorized, qualified or licensed to do business as
      a foreign corporation in, and is in good standing in, each of the
      jurisdictions in which its right, title or interest in or to any of the
      assets held by it or the Subject Business conducted by it, if applicable,
      requires such authorization, qualification or





                                      -8-
   13
      licensing, except where the failure to be so authorized, qualified,
      licensed or in good standing would not be reasonably likely to have a
      Material Adverse Effect with respect to its Subject Business, and (iii)
      has, and in the case of the Related Agreements to be executed by it at or
      prior to the Closing, will have, all requisite corporate power and
      authority to enter into this Agreement and, as applicable, the Related
      Agreements to which it is or will be a party and to perform its
      obligations hereunder and thereunder.

                  (b)     Authorization and Validity of Agreements.  Assuming
      the approval of Occidental's board of directors referred to in Section
      4.3(d):

                          (i)     The execution, delivery and performance by
                  Occidental of this Agreement and the consummation by it of
                  the transactions contemplated hereby have been duly
                  authorized and approved by all necessary corporate or similar
                  action on its part.  This Agreement has been duly and validly
                  executed and delivered by Occidental and is its legal, valid
                  and binding obligation, enforceable against it in accordance
                  with its terms, except as the same may be limited by
                  applicable bankruptcy, insolvency, reorganization, moratorium
                  or other laws related to or affecting creditors' rights
                  generally and by general equity principles.

                          (ii)    The execution, delivery and performance by
                  Occidental and each member of its Group of the Related
                  Agreements to which it or any member of its Group will be a
                  party and the consummation by it and its Group of the
                  transactions contemplated thereby will be, as of the Closing,
                  duly authorized and approved by all necessary corporate or
                  similar action on its or their part.  At the Closing, each of
                  the Related Agreements to which Occidental or any member of
                  its Group will be a party will be duly and validly executed
                  and delivered by Occidental or member and will be upon
                  execution and delivery a legal, valid and binding obligation,
                  enforceable against it or such member in accordance with its
                  terms, except as the same may be limited by applicable
                  bankruptcy, insolvency, reorganization, moratorium or other
                  laws related to or affecting creditors' rights generally and
                  by general equity principles.

                  (c)     Lack of Conflicts.  Assuming satisfaction of the
      condition in Section 4.1(c) and receipt of the Consents contemplated by
      Schedule 4.3(f), and except with respect to the HSR Act as set forth in
      Section 4.1(d), each of the execution, delivery and performance by
      Occidental and each member of its Group of this Agreement and the Related
      Agreements to which any of them is or will be a party and the
      consummation by them of the transactions contemplated hereby and thereby
      does not and, as of the Closing, will not (i) violate (with or without
      the giving of notice or the lapse of time or both) any Legal Requirement
      applicable to any of them or any of their Subsidiaries, other than those
      that would not be reasonably likely to have a Material Adverse Effect
      with respect to its Subject Business, (ii) conflict with, or result in
      the breach of, any provision of the charter or by-laws or similar
      governing or organizational documents of any of them or any of their
      Subsidiaries, (iii) result in the creation of any Encumbrance upon any of
      their assets, other than those contemplated by this Agreement or any of
      the Related Agreements, or those that would not be reasonably likely to
      have a Material Adverse Effect with respect to its Subject Business, or
      (iv) violate, conflict





                                      -9-
   14
      with or result in the breach or termination of or otherwise give any
      other Person the right to terminate, or constitute a default, event of
      default or an event which with notice, lapse of time or both, would
      constitute a default or event of default under the terms of, any
      contract, indenture, lease, mortgage, Government License or other
      agreement or instrument to which any of them or any of their Subsidiaries
      is a party or by which the properties or businesses of any of them or any
      of their Subsidiaries are bound, except for violations, conflicts,
      breaches, terminations and defaults that would not be reasonably likely
      to have a Material Adverse Effect with respect to its Subject Business.

                  (d)     Certain Fees.  Neither Occidental nor any of its
      Affiliates nor any of its officers, directors or employees, on behalf of
      it or such Affiliates, has employed any broker or finder or incurred any
      other liability for any financial advisory fees, brokerage fees,
      commissions or finders' fees in connection with the transactions
      contemplated hereby.

                  (e)     SEC Reports; Financial Statements.

                          (i)     Occidental has filed all material forms,
                  reports and documents required to be filed by it with the SEC
                  since December 31, 1996 (its "SEC Reports").  Occidental's
                  SEC Reports were prepared in all material respects in
                  accordance with the requirements of the Securities Act, or
                  the Exchange Act, as the case may be, and the rules and
                  regulations thereunder, and none of Occidental's SEC Reports,
                  as of the date they were filed with the SEC, contained any
                  untrue statement of a material fact or omitted to state a
                  material fact required to be stated therein or necessary to
                  make the statements therein, in the light of the
                  circumstances under which they were made, not misleading.

                          (ii)    The financial statements (including any notes
                  thereto) contained in Occidental's SEC Reports were prepared
                  in accordance with GAAP throughout the periods indicated
                  (except as may be indicated in the notes thereto and except
                  that financial statements included with quarterly reports on
                  Form 10-Q do not contain all GAAP notes to such financial
                  statements) and each fairly presents the consolidated (or
                  combined, as applicable) financial position, results of
                  operations and changes in stockholders' equity and cash flows
                  of Occidental and its subsidiaries as at the respective dates
                  thereof and for the respective periods indicated therein
                  (subject, in the case of unaudited statements, to normal and
                  recurring year-end adjustments).

                  (f)     Absence of Certain Changes.  Since December 31, 1996,
      (i) Occidental and its Affiliates have not incurred any material
      liabilities or obligations, fixed, contingent, accrued or otherwise, that
      relate to or are allocable to its Subject Business and that have had or
      are reasonably likely to have a Material Adverse Effect with respect to
      its Subject Business, (ii) Occidental and its Affiliates have conducted
      its Subject Business in all material respects in the ordinary course,
      consistent with past practice, and (iii) no event, occurrence or other
      matter has occurred that is reasonably likely to have a Material Adverse
      Effect with respect to the Subject Business of Occidental, provided that
      this determination shall be made without regard to any change in general
      economic or political conditions or any change in raw





                                      -10-
   15
      materials prices, product prices, industry capacity or other matter of
      industry-wide application that affects the Partnership's Subject Business
      and Occidental's Subject Business in a substantially similar way.

      2.3         Representations and Warranties of Lyondell.  Except as set
forth on Schedule 2.3, Lyondell represents and warrants to each other Party as
follows:

                  (a)     Organization, Good Standing and Power.  Lyondell and
      each member of its Group (i) is a corporation duly organized, validly
      existing and in good standing under the laws of the State of Delaware and
      has the corporate power and authority to own, lease and operate its
      assets, (ii) is duly authorized, qualified or licensed to do business as
      a foreign corporation or other organization in, and is in good standing
      in, each of the jurisdictions in which its right, title or interest in or
      to any of the assets held by it requires such authorization,
      qualification or licensing, except where the failure to be so authorized,
      qualified, licensed or in good standing would not be reasonably likely to
      have a Material Adverse Effect with respect to the Partnership's Subject
      Business, and (iii) has, and in the case of the Related Agreements to be
      executed by it at or prior to the Closing, will have, all requisite
      corporate power and authority, or power and authority under its
      constituent documents, to enter into this Agreement and, as applicable,
      the Related Agreements to which it is or will be a party and to perform
      its obligations hereunder and thereunder.

                  (b)     Authorization and Validity of Agreements.

                          (i)     The execution, delivery and performance by
                  Lyondell of this Agreement and the consummation by it of the
                  transactions contemplated hereby have been duly authorized
                  and approved by all necessary corporate or similar action on
                  its part.  This Agreement has been duly and validly executed
                  and delivered by Lyondell and is its legal, valid and binding
                  obligation, enforceable against it in accordance with its
                  terms, except as the same may be limited by applicable
                  bankruptcy, insolvency, reorganization, moratorium or other
                  laws related to or affecting creditors' rights generally and
                  by general equity principles.

                          (ii)    The execution, delivery and performance by
                  Lyondell and each member of its Group of the Related
                  Agreements to which it or any member of its Group will be a
                  party and the consummation by it and its Group of the
                  transactions contemplated thereby will be, as of the Closing,
                  duly authorized and approved by all necessary corporate or
                  similar action on its or their part.  At the Closing, each of
                  the Related Agreements to which Lyondell or any member of its
                  Group will be a party will be duly and validly executed and
                  delivered by Lyondell or member and will be upon execution
                  and delivery a legal, valid and binding obligation,
                  enforceable against it or such member in accordance with its
                  terms, except as the same may be limited by applicable
                  bankruptcy, insolvency, reorganization, moratorium or other
                  laws related to or affecting creditors' rights generally and
                  by general equity principles.





                                      -11-
   16
                  (c)     Lack of Conflicts.   Except with respect to the HSR
      Act as set forth in Section 4.1(d), each of the execution, delivery and
      performance by Lyondell and each member of its Group of this Agreement
      and the Related Agreements to which any of them is or will be a party and
      the consummation by them of the transactions contemplated hereby and
      thereby does not and, as of the Closing, will not (i) violate (with or
      without the giving of notice or the lapse of time or both) any Legal
      Requirement applicable to any of them or any of their Subsidiaries, other
      than those that would not be reasonably likely to have a Material Adverse
      Effect with respect to Lyondell, (ii) conflict with, or result in the
      breach of, any provision of the charter or by-laws or similar governing
      or organizational documents of any of them or any of their Subsidiaries,
      (iii) result in the creation of any Encumbrance upon any of their assets,
      other than those contemplated by this Agreement or any of the Related
      Agreements, or those that would not be reasonably likely to have a
      Material Adverse Effect with respect to Lyondell, or (iv) violate,
      conflict with or result in the breach or termination of or otherwise give
      any other Person the right to terminate, or constitute a default, event
      of default or an event which with notice, lapse of time or both, would
      constitute a default or event of default under the terms of, any
      contract, indenture, lease, mortgage, Government License or other
      agreement or instrument to which any of them or any of their Subsidiaries
      is a party or by which the properties or businesses of any of them or any
      of their Subsidiaries are bound, except for violations, conflicts,
      breaches, terminations and defaults that would not be reasonably likely
      to have a Material Adverse Effect with respect to Lyondell.

                  (d)     Certain Fees.  Neither Lyondell nor any of its
      Affiliates nor any of its officers, directors or employees, on behalf of
      it or such Affiliates, has employed any broker or finder or incurred any
      other liability for any financial advisory fees, brokerage fees,
      commissions or finders' fees in connection with the transactions
      contemplated hereby.

                  (e)     Joint Proxy Statement.  The Joint Proxy Statement was
      prepared in all material respects in accordance with the requirements of
      the Securities Act, or the Exchange Act, as the case may be, and the
      rules and regulations thereunder, and, as of the date of the
      Stockholders' Meetings and insofar as it relates to the Subject Business
      of Lyondell, did not contain any untrue statement of a material fact or
      omit to state a material fact required to be stated therein or necessary
      to make the statements therein, in the light of the circumstances under
      which they were made, not misleading.

                  (f)     Title to Lyondell Units.  Without giving effect to
      this Agreement or the transactions contemplated hereby, Lyondell LP and
      Lyondell GP each owns the number of Units set forth in Section 2.1 of the
      Partnership Agreement opposite its name.  Except as contemplated by this
      Agreement, there are no outstanding subscriptions, options, convertible
      securities, warrants or calls of any kind issued or granted by, or
      binding upon, the Partnership or any member of the Lyondell Group to
      purchase or otherwise acquire or to sell or otherwise dispose of any
      security of or equity interest in the Partnership.





                                      -12-
   17
      2.4         Representations and Warranties of Millennium.  Except as set
forth on Schedule 2.4, Millennium represents and warrants to each other Party
as follows:

                  (a)     Organization, Good Standing and Power.  Millennium
      and each member of its Group (i) is a corporation or a limited liability
      company duly organized, validly existing and in good standing under the
      laws of the jurisdiction of its incorporation or organization and has the
      corporate power and authority or power under its constituent documents to
      own, lease and operate its assets, (ii) is duly authorized, qualified or
      licensed to do business as a foreign corporation or other organization
      in, and is in good standing in, each of the jurisdictions in which its
      right, title or interest in or to any of the assets held by it requires
      such authorization, qualification or licensing, except where the failure
      to be so authorized, qualified, licensed or in good standing would not be
      reasonably likely to have a Material Adverse Effect with respect to the
      Partnership's Subject Business, and (iii) has, and in the case of the
      Related Agreements to be executed by it at or prior to the Closing, will
      have, all requisite corporate power and authority, or power and authority
      under its constituent documents, to enter into this Agreement and, as
      applicable, the Related Agreements to which it is or will be a party and
      to perform its obligations hereunder and thereunder.

                  (b)     Authorization and Validity of Agreements.

                          (i)     The execution, delivery and performance by
                  Millennium of this Agreement and the consummation by it of
                  the transactions contemplated hereby have been duly
                  authorized and approved by all necessary corporate or similar
                  action on its part.  This Agreement has been duly and validly
                  executed and delivered by Millennium and is its legal, valid
                  and binding obligation, enforceable against it in accordance
                  with its terms, except as the same may be limited by
                  applicable bankruptcy, insolvency, reorganization, moratorium
                  or other laws related to or affecting creditors' rights
                  generally and by general equity principles.

                          (ii)    The execution, delivery and performance by
                  Millennium and each member of its Group of the Related
                  Agreements to which it or any member of its Group will be a
                  party and the consummation by it and its Group of the
                  transactions contemplated thereby will be, as of the Closing,
                  duly authorized and approved by all necessary corporate or
                  similar action on its or their part.  At the Closing, each of
                  the Related Agreements to which Millennium or any member of
                  its Group will be a party will be duly and validly executed
                  and delivered by Millennium or member and will be upon
                  execution and delivery a legal, valid and binding obligation,
                  enforceable against it or such member in accordance with its
                  terms, except as the same may be limited by applicable
                  bankruptcy, insolvency, reorganization, moratorium or other
                  laws related to or affecting creditors' rights generally and
                  by general equity principles.

                  (c)     Lack of Conflicts.  Except with respect to the HSR
      Act as set forth in Section 4.1(d), each of the execution, delivery and
      performance by Millennium and each member of its Group of this Agreement
      and the Related Agreements to which any of them is or will be a party and
      the consummation by them of the transactions contemplated hereby 





                                      -13-
   18
      and thereby does not and, as of the Closing, will not (i) violate (with or
      without the giving of notice or the lapse of time or both) any Legal
      Requirement applicable to any of them or any of their Subsidiaries, other
      than those that would not be reasonably likely to have a Material Adverse
      Effect with respect to Millennium, (ii) conflict with, or result in the
      breach of, any provision of the charter or by- laws of any of them or any
      of their Subsidiaries, (iii) result in the creation of any Encumbrance
      upon any of their assets, other than those contemplated by this Agreement
      or any of the Related Agreements, or those that would not be reasonably
      likely to have a Material Adverse Effect with respect to Millennium, or
      (iv) violate, conflict with or result in the breach or termination of or
      otherwise give any other Person the right to terminate, or constitute a
      default, event of default or an event which with notice, lapse of time or
      both, would constitute a default or event of default under the terms of,
      any contract, indenture, lease, mortgage, Government License or other
      agreement or instrument to which any of them or any of their Subsidiaries
      is a party or by which the properties or businesses of any of them or any
      of their Subsidiaries are bound, except for violations, conflicts,
      breaches, terminations and defaults that would not be reasonably likely
      to have a Material Adverse Effect with respect to Millennium.

                  (d)     Certain Fees. Neither Millennium nor any of its
      Affiliates nor any of its officers, directors or employees, on behalf of
      it or such Affiliates, has employed any broker or finder or incurred any
      other liability for any financial advisory fees, brokerage fees,
      commissions or finders' fees in connection with the transactions
      contemplated hereby.

                  (e)     Joint Proxy Statement.  The Joint Proxy Statement was
      prepared in all material respects in accordance with the requirements of
      the Securities Act, or the Exchange Act, as the case may be, and the
      rules and regulations thereunder, and, as of the date of the
      Stockholders' Meetings and insofar as it relates to the Subject Business
      of Millennium, did not contain any untrue statement of a material fact or
      omit to state a material fact required to be stated therein or necessary
      to make the statements therein, in the light of the circumstances under
      which they were made, not misleading.

                  (f)     Title to Millennium Units. Without giving effect to
      this Agreement or the transactions contemplated hereby, Millennium LP and
      Millennium GP each owns the number of Units set forth in Section 2.1 of
      the Partnership Agreement opposite its name.  Except as contemplated by
      this Agreement, there are no outstanding subscriptions, options,
      convertible securities, warrants or calls of any kind issued or granted
      by, or binding upon, the Partnership or any member of the Millennium
      Group to purchase or otherwise acquire or to sell or otherwise dispose of
      any security of or equity interest in the Partnership.


                                   SECTION 3
                             ADDITIONAL AGREEMENTS

      3.1         Access to Information.  Each of Occidental and the
Partnership agrees that, during the period commencing on the date hereof and
ending at the Closing, (i) it will give or cause to be given to any other Party
and its representatives reasonable access during normal business hours to





                                      -14-
   19
the offices, plants, properties, books and records relating to its Subject
Business as such other Party may reasonably request, (ii) it will furnish or
cause to be furnished to any other Party, such financial and operating data and
any other information with respect to the business and properties of its
Subject Business as such other Party may reasonably request (provided such data
and information need only be furnished to the extent it was prepared in the
ordinary course) and (iii) any other Party and its representatives shall be
entitled to reasonable access during normal business hours to the
representatives, officers, employees and contractors of such Party who are
involved in its Subject Business as such other Party may reasonably request;
provided, that Lyondell and Millennium also agree to the foregoing provisions
to the extent that any of the foregoing remain in their possession and have not
been transferred to the Partnership; provided, further that, after
consultation, to the extent permissible, with such other Party, such Party may
restrict access and provision of information to the extent it reasonably
believes necessary to (w) comply with existing confidentiality agreements with
third parties (provided that, upon such other Party's reasonable request, it
shall use its commercially reasonable efforts to secure waivers of any such
confidentiality agreements), (x) ensure compliance with antitrust laws, (y)
preserve the secrecy of confidential information to the extent not related to
its Subject Business and (z) preserve legal privilege; and provided, further
that any access or information obtained by any Party and its representatives in
accordance with this Section 3.1 and otherwise in connection with the
consummation of the transactions contemplated by this Agreement and the Related
Agreements shall be subject to the terms and conditions of the Confidentiality
Agreement.

      3.2         Conduct of the Occidental Subject Business Pending the
Closing Date.  Occidental agrees that, except as required or contemplated by
this Agreement or otherwise consented to or approved in writing by the
Partnership, during the period commencing on the date hereof and ending on the
Closing Date, it will and will cause its Affiliates to:

                  (a)     use its commercially reasonable efforts to operate
      and maintain its Subject Business in all material respects only in the
      usual, regular and ordinary manner consistent with past practice
      (including undertaking scheduled or necessary "turnarounds" or other
      maintenance work and including offsite storage, treatment and disposal of
      chemical substances generated prior to the Closing) and, to the extent
      consistent with such operation and maintenance, use commercially
      reasonable efforts to preserve the present business organization of its
      Subject Business intact, keep available the services of, and good
      relations with, the present employees and preserve present relationships
      with all persons having business dealings with its Subject Business,
      except in each case for such matters that, individually and in the
      aggregate, do not and are not reasonably likely to have a Material
      Adverse Effect on its Subject Business;

                  (b)     maintain its books, accounts and records relating to
      its Subject Business in the usual, regular and ordinary manner, on a
      basis consistent with past practice, comply in all material respects with
      all Legal Requirements and contractual obligations applicable to its
      Subject Business or to the conduct of its Subject Business and perform
      all of its material obligations relating to its Subject Business;





                                      -15-
   20
                  (c)     not (i) modify or change in any material respect any
      of its Contributed Assets or dispose of any material Contributed Asset
      except for (A) inventory, equipment, supplies and other Contributed
      Assets sold or otherwise disposed of in the ordinary course of business
      and (B) any Contributed Assets that in the ordinary course of business
      are replaced with substantially similar Contributed Assets, (ii) except
      in the ordinary course of business after consultation with the
      Partnership, (x) enter into any contract, commitment or agreement that
      would be material to the operation of its Subject Business or use of the
      Contributed Assets or, except as expressly contemplated by this Agreement
      or expressly contemplated by or required pursuant to their respective
      terms, modify or change in any material respect any obligation under any
      such contract, commitment or agreement, (y) modify or change in any
      material respect any obligation under its Government Licenses, (z) modify
      or change in any material respect the manner in which the products
      produced by its Subject Business are marketed and sold, or (iii) enter
      into interest rate protection or other hedging agreements (except for
      hydrocarbon hedging agreements entered into in the ordinary course and
      expiring prior to December 31, 1998) relating to its Subject Business;

                  (d)     not waive any material claims or rights relating to
      its Subject Business;

                  (e)     after obtaining Knowledge thereof, give notice to the
      Partnership of any claim or litigation (threatened or instituted) or any
      other event or occurrence which could reasonably be expected to have a
      Material Adverse Effect on its Contributed Assets or Subject Business,
      other than the types of events, occurrences or other matters referred to
      in the proviso set forth in Section 2.2(f)(iii);

                  (f)     not take any action that is reasonably likely to
      result in its representations and warranties in Section 2 hereof, or in
      the form of Occidental Contribution Agreement, not being true in all
      material respects as of the Closing Date; and

                  (g)     not agree, whether in writing or otherwise, to take
      any action it has agreed pursuant to this Section 3.2 not to take;

provided, however, that notwithstanding anything to the contrary contained in
this Section 3.2, prior to the Closing Date the Occidental Group and the
Partnership will act independently of each other in making decisions as to the
research and development, raw materials, manufacturing, pricing, marketing and
distribution of their products.  It is acknowledged by the Parties that the
Originator Receivables Sale Agreement dated as of October 27, 1998, by and
among Occidental Receivables Inc., OCC and other parties, has been terminated
with respect to Oxy Petrochemicals.

      3.3         Conduct of the Partnership Subject Business Pending the
Closing Date.  The Partnership agrees that, except as required or contemplated
by approvals or authorizations (including the Strategic Plan) by or of the
Partnership Governance Committee prior to the date hereof or by this Agreement
(including, without limitation, Schedule 3.3 hereto) or otherwise consented to
or approved in writing by Occidental, during the period commencing on the date
hereof and ending on the Closing Date, it will and will cause its Affiliates
to:





                                      -16-
   21
                  (a)     use its commercially reasonable efforts to operate
      and maintain its Subject Business in all material respects only in a
      usual, regular and ordinary manner consistent with the Strategic Plan
      (including undertaking scheduled or necessary "turnarounds" or other
      maintenance work and including offsite storage, treatment and disposal of
      chemical substances generated prior to the Closing) and, to the extent
      consistent with such operation and maintenance, use commercially
      reasonable efforts to preserve the present business organization of its
      Subject Business intact, keep available the services of, and good
      relations with, the present employees and preserve present relationships
      with all persons having business dealings with its Subject Business,
      except in each case for such matters that, individually and in the
      aggregate, do not and are not reasonably likely to have a Material
      Adverse Effect on its Subject Business;

                  (b)     maintain its books, accounts and records relating to
      its Subject Business in the usual, regular and ordinary manner, comply in
      all material respects with all Legal Requirements and contractual
      obligations applicable to its Subject Business or to the conduct of its
      Subject Business and perform all of its material obligations relating to
      its Subject Business;

                  (c)     not (i) modify or change in any material respect any
      of its assets or dispose of any material asset except for (A) inventory,
      equipment, supplies and other assets sold or otherwise disposed of in the
      ordinary course of business and (B) any assets that in the ordinary
      course of business are replaced with substantially similar assets, (ii)
      except in the ordinary course of business after consultation with
      Occidental, (x) enter into any contract, commitment or agreement that
      would be material to the operation of its Subject Business or use of its
      assets or, except as expressly contemplated by this Agreement or
      expressly contemplated by or required pursuant to their respective terms,
      modify or change in any material respect any obligation under any such
      contract, commitment or agreement, (y) modify or change in any material
      respect any obligation under its Government Licenses, (z) modify or
      change in any material respect the manner in which the products produced
      by its Subject Business are marketed and sold, or (iii) enter into
      interest rate protection or other hedging agreements (except for
      hydrocarbon hedging agreements entered into in the ordinary course and
      expiring prior to December 31, 1998) relating to its Subject Business;
      provided, that, for purposes of (i) and (ii), "material" shall mean a
      change or modification that is subject to the unanimous voting
      requirement of Section 6.7 of the Partnership Agreement;

                  (d)     not waive any material claims or rights relating to
      its Subject Business;

                  (e)     after obtaining Knowledge thereof, give notice to
      Occidental of any claim or litigation (threatened or instituted) or any
      other event or occurrence which could reasonably be expected to have a
      Material Adverse Effect on its assets or Subject Business, other than the
      types of events, occurrences or other matters referred to in the proviso
      set forth in Section 2.1(f)(iii);

                  (f)     not take any action that is reasonably likely to
      result in its representations and warranties in Section 2 hereof not
      being true in all material respects as of the Closing Date;





                                      -17-
   22
                  (g)     not to make any distributions that are not in
      compliance with Section 3.1 of the Partnership Agreement; and

                  (h)     not agree, whether in writing or otherwise, to take
      any action it has agreed pursuant to this Section 3.3 not to take;

provided, however, that notwithstanding anything to the contrary contained in
this Section 3.3, prior to the Closing Date the Occidental Group and the
Partnership will act independently of each other in making decisions as to the
research and development, raw materials, manufacturing, pricing, marketing and
distribution of their products.

      3.4         Further Actions.

                  (a)     Each Party will use its commercially reasonable
      efforts to take, or cause to be taken, all other action and do, or cause
      to be done, all other things necessary, proper or appropriate to resolve
      the objections, if any, as may be asserted by any Authority with respect
      to the transactions contemplated hereby under any antitrust laws or
      regulations; provided that no Party shall be required to take any action
      that could have any material adverse effect on its or its Affiliates'
      business, operations, prospects, assets, condition (financial or
      otherwise) or results of operations or that would, or would be reasonably
      likely to, materially frustrate the financial or other business benefits
      reasonably expected to be derived by any Party from the transactions
      contemplated by this Agreement.

                  (b)     Subject to the terms and conditions hereof, each
      Party agrees to act in good faith and to use its commercially reasonable
      efforts to take, or cause to be taken, all actions and to do, or cause to
      be done, all things necessary, proper or advisable to consummate and make
      effective the transactions contemplated by this Agreement and under the
      Related Agreements to be entered into by such Party or its Affiliates at
      Closing, and to confirm that such transactions have been accomplished,
      including without limitation, using all commercially reasonable efforts:
      (i) to obtain and effect prior to the Closing Date all necessary Consents
      and Filings; and (ii) to, in the case of Occidental, obtain prior to the
      Closing Date all Government Licenses or consents to the transfer of any
      Government Licenses that are transferable by it or its Affiliates
      necessary to consummate the transactions contemplated hereby and by the
      Related Agreements and to allow for the prudent and uninterrupted
      operation of the Subject Business by the Partnership after the Closing.
      Each Party shall furnish to the other Party and its Affiliates such
      necessary information and assistance as the other may reasonably request
      in connection with its preparation of any such Filings or other materials
      required in connection with the foregoing.

                  (c)     Occidental shall use its commercially reasonable
      efforts to procure all Consents that are necessary to transfer its
      Subject Business to the Partnership.  Notwithstanding any other provision
      of this Agreement to the contrary, the Parties hereto acknowledge and
      agree that at the Closing Occidental or any Occidental Partner, as
      applicable, will not assign to the Partnership any Contract or warranties
      which by their terms require Consent from any other contracting party
      thereto unless any such Consent has been obtained prior to the Closing





                                      -18-
   23
      Date.  Before the Closing, the other Parties and the Partnership will use
      their commercially reasonable efforts and cooperate with Occidental and
      the Occidental Partners (together, the "Contracting Party") in obtaining
      any necessary Consents to the assignment of the Contracts, including,
      without limitation, by furnishing to the Contracting Party or other
      parties to any Contract summary financial information and other
      information with respect to the Partnership reasonably requested by the
      Contracting Party or such other parties and taking any such other actions
      (which, subject to any provisions to the contrary included in any Related
      Agreement, shall not include the incurrence of any expense not otherwise
      required to be incurred) as the Contracting Party or such other parties
      may reasonably request for the purpose of obtaining any releases, waivers
      or terminations as the Contracting Party may reasonably request on behalf
      of itself or any Affiliate.  No representation is made by the Contracting
      Party with respect to whether any Consent to assign a Contract will be
      obtainable, and in no event shall the initial capital contributions be
      subject to reduction as a result of any Contract not being assigned to
      the Partnership at the Closing by virtue of the necessary Consent not
      being obtained.  Following the Closing, the Partnership, Occidental and
      the Occidental Partners shall cooperate with each other and use
      commercially reasonable efforts to obtain those Consents that were not
      obtained prior to the Closing and (i) if such Consents are obtained
      following the Closing, Occidental and the Occidental Partners shall
      execute and deliver any other and further instruments of assignment,
      assumption, transfer and conveyance and take such other and further
      action as the Partnership may request in order to assign to the
      Partnership any Contract or warranties to which such Consents relate and
      (ii) pending such transfer or issuance to the Partnership, shall provide,
      to the extent it may lawfully do so, the Partnership with the benefits of
      any such Contracts, in which case, as provided for in the Occidental
      Contribution Agreement, the Partnership shall promptly assume and
      discharge (or reimburse Occidental or its Affiliate for) all obligations
      and liabilities associated with the benefits of such Contracts so made
      available to the Partnership.

                  (d)     Occidental shall keep each other Party fully informed
      from time to time as any other Party shall reasonably request as to the
      status of all Consents being sought by Occidental or a Occidental Partner
      pursuant to Section 3.4(c).

                  (e)     Each Party shall furnish to the other Party such
      information, cooperation and assistance as reasonably may be requested in
      connection with the foregoing.

                  (f)     Each Party shall negotiate and otherwise act in good
      faith to complete, execute and deliver the Related Agreements at the
      Closing and to effect the Closing at the earliest practicable date.

      3.5         Notifications.  Each Party shall notify the other Parties and
keep them advised as to (i) any litigation or administrative proceeding that is
either pending or, to its Knowledge, threatened against such Party which
challenges the transactions contemplated hereby; (ii) in the case of the
Partnership or Occidental, any material damage to or destruction of its Subject
Business and (iii) any fact of which such Party has Knowledge that indicates
that any condition to Closing is reasonably likely not to be satisfied in a
timely fashion.





                                      -19-
   24
      3.6         Employee Matters.

                  (a)     Substantially all employees of Occidental, OCC, Oxy
      Petrochemicals or one of the Occidental Partners who are associated
      primarily with Occidental's Subject Business shall be offered employment
      with the Partnership pursuant to the terms of the Occidental Contribution
      Agreement.

                  (b)     The Partnership shall provide benefits to such
      employees who become employees of the Partnership under the benefit plans
      and programs of the Partnership upon employment with the Partnership,
      subject to the more specific provisions of the Occidental Contribution
      Agreement.

                  (c)     No provision of this Agreement shall require OCC, Oxy
      Petrochemicals or any of the Occidental Partners to fail to comply with
      the terms of any current collective bargaining agreement.

      3.7         Partnership Unanimous Consent Items.  No action that requires
the consent of Representatives of both Lyondell and Millennium pursuant to
Section 6.7 of the Partnership Agreement shall be taken prior to the Closing
without the consent of Occidental (other than actions regarding this Agreement
and the transactions contemplated hereby).

                                   SECTION 4
                             CONDITIONS TO CLOSING

      4.1         Conditions Precedent to Obligations of All Parties.  The
respective obligations of the Parties to consummate the transactions
contemplated by this Agreement shall be subject to the satisfaction on or prior
to the Closing Date of each of the following conditions:

                  (a)     No Injunction, etc.  No preliminary or permanent
      injunction or other order  issued by any federal or state court of
      competent jurisdiction in the United States or by any United States
      federal or state governmental or regulatory body or any statute, rule,
      regulation or executive order promulgated or enacted by any United States
      federal or state governmental authority shall be in effect which
      materially restrains, enjoins or otherwise prohibits (i) the transactions
      contemplated hereby; (ii) the ownership by the Partnership (including
      enjoyment of any rights relating thereto) of its Subject Business or
      Occidental's Subject Business at and after the Closing; or (iii) the
      operation by the Partnership of its Subject Business or Occidental's
      Subject Business at and after the Closing; and no Proceeding seeking any
      such injunction or order shall be pending; provided, that before any
      determination is made to the effect that this condition has not been
      satisfied, each Party shall each use commercially reasonable efforts to
      have such order or injunction lifted, vacated or dismissed.

                  (b)     Tier 2 Related Agreements.  The Parties shall have
      reached agreement with respect to definitive execution forms of the Tier
      2 Related Agreements in accordance with Section 1.2.





                                      -20-
   25
                  (c)     Government Licenses and Consents.  Occidental shall
      have obtained and effected all Government Licenses and Consents required
      from any Authority for the consummation of the transactions contemplated
      hereunder and under the Related Agreements to be entered into at the
      Closing and required to allow for the prudent and uninterrupted operation
      of its Subject Business by the Partnership after the Closing in a manner
      consistent with past practices, except for those Government Licenses and
      Consents, the absence of which is not, in the aggregate, reasonably
      likely to have a Material Adverse Effect with respect to Occidental's
      Subject Business.

                  (d)     HSR Act.  The waiting period applicable to the
      Closing under the HSR Act shall have expired or been terminated, and no
      consent, approval, permit or authorization in connection therewith shall
      impose terms or conditions that would have, or would be reasonably likely
      to have, a material adverse effect on any Party (assuming the Closing has
      taken place) or that would, or would be reasonably likely to, materially
      frustrate the financial or other business benefits reasonably expected to
      be derived by any Party from the transactions contemplated by this
      Agreement.

      4.2         Conditions Precedent to Obligations of the Partnership.  The
obligations of the Partnership under this Agreement are subject to the
satisfaction (or waiver by the Partnership) on or prior to the Closing Date of
each of the following conditions:

                  (a)     Accuracy of Representations and Warranties.
      Notwithstanding any investigation, inspection or evaluation conducted or
      notice or Knowledge obtained by any member of the Equistar Group, all
      representations and warranties of members of the Occidental Group
      contained in this Agreement and the Related Agreements that contain
      qualifications and exceptions relating to materiality or Material Adverse
      Effect shall be true and correct on and as of the Closing Date, and all
      other representations and warranties of the members of such Group
      contained in such agreements shall be true and correct in all material
      respects as of the Closing Date.

                  (b)     Performance of Agreements.  Occidental and its
      Affiliates shall in all material respects have performed and complied
      with all obligations and agreements contained in this Agreement, and
      executed all agreements and documents (including the Tier 1 Related
      Agreements and the Tier 2 Related Agreements) to be performed, complied
      with or executed by it or them on or prior to the Closing Date.

                  (c)     No Material Adverse Change.  After the date of this
      Agreement, no event, occurrence or other matter shall have occurred that
      is reasonably likely to have a Material Adverse Effect with respect to
      Occidental's Subject Business, provided that this determination shall be
      made without regard to any change in general economic or political
      conditions or any change in raw materials prices, product prices,
      industry capacity or other matter of industry-wide application that
      affects the Partnership's Subject  Business and Occidental's Subject
      Business in a substantially similar way.





                                      -21-
   26
                  (d)     Officer's Certificates.  The Partnership shall have
      received a certificate, dated the Closing Date, signed by the President
      or a Vice President of Occidental to the effect that, to the Knowledge of
      Occidental, the conditions specified in the above paragraphs have been
      fulfilled.

      4.3         Conditions Precedent to Obligations of Occidental.  The
obligations of Occidental under this Agreement are subject to the satisfaction
(or waiver by Occidental) on or prior to the Closing Date of each of the
following conditions:

                  (a)     Accuracy of Representations and Warranties.
      Notwithstanding any investigation, inspection or evaluation conducted or
      notice or Knowledge obtained by any member of the Occidental Group, all
      representations and warranties of the Partnership and of members of the
      Lyondell Group and the Millennium Group contained in this Agreement and
      the Related Agreements that contain qualifications and exceptions
      relating to materiality or Material Adverse Effect shall be true and
      correct on and as of the Closing Date, and all other representations and
      warranties of such Persons contained in such agreements shall be true and
      correct in all material respects as of the Closing Date.

                  (b)     Performance of Agreements.  Each of the Partnership,
      Lyondell and its Affiliates and Millennium and its Affiliates shall in
      all material respects have performed and complied with all obligations
      and agreements contained in this Agreement, and executed all agreements
      and documents (including the Tier 1 Related Agreements and the Tier 2
      Related Agreements) to be performed, complied with or executed by it or
      them on or prior to the Closing Date.

                  (c)     No Material Adverse Change.  After the date of this
      Agreement, no event, occurrence or other matter shall have occurred that
      is reasonably likely to have a Material Adverse Effect with respect to
      the Partnership's Subject Business, provided that this determination
      shall be made without regard to any change in general economic or
      political conditions or any change in raw materials prices, product
      prices, industry capacity or other matter of industry-wide application
      that affects the Partnership's Subject Business and Occidental's Subject
      Business in a substantially similar way.

                  (d)     Board of Directors Approval.  This Agreement and the
      Tier 1 Related Agreements, and the transactions contemplated by such
      agreements, shall have been duly authorized and approved by Occidental's
      board of directors.

                  (e)     Officer's Certificates.  Occidental shall have
      received certificates, dated the Closing Date, signed by the President or
      a Vice President of each of the Partnership, Lyondell and Millennium to
      the effect that, to the Knowledge of such Party, the conditions specified
      in the above paragraphs have been fulfilled; provided, that, with respect
      to the conditions set forth in Sections 4.3(a) and 4.3(b), such
      certificates shall only concern the accuracy of representations and
      warranties and performance of agreements of the Partnership, the Lyondell
      Group and the Millennium Group, respectively.





                                      -22-
   27
                  (f)     Third Party Consents.  All Consents of any third
      party listed on Schedule 4.3(f) shall have been obtained.

                                   SECTION 5
                             TERMINATION AND WAIVER

      5.1         General.  This Agreement may be terminated and the
transactions contemplated herein and in the Related Agreements may be abandoned
at any time prior to the Closing:

                  (a)     by the written consent of the Parties;

                  (b)     by the Partnership, by notice to Occidental, if there
      has been a material misrepresentation or a breach of an agreement by
      Occidental in this Agreement that (i) if such misrepresentation or breach
      existed on the Closing Date, would constitute a failure to satisfy the
      conditions to Closing set forth in Section 4.2(b) and (ii) has not been
      cured and cannot reasonably be cured within 30 days after all other
      conditions to Closing have been satisfied;

                  (c)     by Occidental, by notice to the Partnership, if there
      has been a material misrepresentation or a breach of an agreement by any
      of the Partnership, Lyondell or Millennium in this Agreement that (i) if
      such misrepresentation or breach existed on the Closing Date, would
      constitute a failure to satisfy the conditions to Closing set forth in
      Section 4.3(b) and (ii) has not been cured and cannot reasonably be cured
      within 30 days after all other conditions to Closing have been satisfied;

                  (d)     by any Party, by notice to each other Party, if after
      the date hereof and prior to the Closing any final, non-appealable order
      or injunction shall be issued by any federal or state court of competent
      jurisdiction in the United States or by any United States Authority, or
      any Legal Requirement shall be promulgated or enacted by any United
      States Authority, that would have the effect of prohibiting or making
      unlawful the performance of this Agreement, the execution, delivery or
      performance of any Related Agreement or the consummation of the Closing;
      and

                  (e)     by any Party, by notice to each other Party, in the
      event that, for any reason, the Closing does not occur on or before
      December 31, 1998; provided, however, that if the Closing does not occur
      due to the act or omission of one of the Parties, that Party may not
      terminate this Agreement pursuant to the provisions of this Section
      5.1(e).

      5.2         Effect of Termination.  In the event of any termination of
this Agreement as provided above, this Agreement shall forthwith become wholly
void and of no further force and effect and there shall be no liability on the
part of any Party, its Subsidiaries or their respective officers or directors;
provided, however, that upon any such termination the obligations of the
Parties with respect to this Section 5, expenses under Section 6.10 and
confidentiality under Section 6.6 shall remain in full force and effect; and
provided, further, that nothing herein will relieve any party from liability
for damages for any breach of this Agreement.





                                      -23-
   28
                                   SECTION 6
                                 MISCELLANEOUS

      6.1         Successors and Assigns.  Except as may be expressly provided
herein, this Agreement shall be binding upon and inure to the benefit of the
successors of all of the Parties.  No Party may otherwise assign or delegate
any of its rights or obligations under this Agreement without the prior written
consent of all of the other Parties, which consent shall be in the sole and
absolute discretion of each such Party.  Any purported assignment or delegation
without such consent shall be void and ineffective.

      6.2         Benefits of Agreement Restricted to Parties.  This Agreement
is made solely for the benefit of the Parties, and no other Person (including
employees) shall have any right, claim or cause of action under or by virtue of
this Agreement.

      6.3         Notices.  All notices, requests and other communications that
are required or may be given under this Agreement shall, unless otherwise
provided for elsewhere in this Agreement, be in writing and shall be deemed to
have been duly given if and when (i) transmitted by telecopier facsimile with
proof of confirmation from the transmitting machine or (ii) delivered by
commercial courier or other hand delivery, as follows:


                                                
Equistar Chemicals, LP:                            Occidental Petroleum Corporation:
Gerald A. O'Brien                                  10889 Wilshire Boulevard
Vice President and Secretary                       Los Angeles, California 90024
Equistar Chemicals, LP                             Attention:  President
1221 McKinney Street                               Telecopy Number: (310) 443-6977
Houston, Texas 77010
Telecopy Number: (713) 309-4718

with a copy to:                                    with a copy to:

Baker & Botts, L.L.P.                              Occidental Petroleum Corporation
910 Louisiana Street                               10889 Wilshire Boulevard
Houston, Texas 77002                               Los Angeles, California 90024
Attention: Stephen A. Massad                       Attention:  General Counsel
Telecopy Number: (713) 229-1522                    Telecopy Number: (310) 443-6333

Lyondell Petrochemical Company:                    Millennium Chemicals Inc.:
Kerry A. Galvin                                    George H. Hempstead, III
Chief Corporate Counsel and                        Senior Vice President,
  Corporate Secretary                                Law and Administration and Secretary
Lyondell Petrochemical Company                     Millennium Chemicals Inc.
1221 McKinney Street                               99 Wood Avenue South
Houston, Texas 77010                               Iselin, New Jersey 08830
Telecopy Number:  (713) 309-4718                   Telecopy Number: 908-603-6857






                                      -24-
   29
      6.4         Severability.  In the event that any provision of this
Agreement shall finally be determined to be unlawful, such provision shall, so
long as the economic and legal substance of the transactions contemplated
hereby is not affected in any materially adverse manner as to any of the
Parties, be deemed severed from this Agreement and every other provision of
this Agreement shall remain in full force and effect.

      6.5         Press Releases.  Unless otherwise mutually agreed, no Party
shall make or authorize any public release of information regarding the matters
contemplated by, or any provisions or terms of, this Agreement or the Related
Agreements, and Occidental shall not make or authorize any public release of
information regarding the Partnership, except (i) that a press release or press
releases in mutually agreed upon form or forms shall be issued by the Parties
as promptly as is practicable following the execution of this Agreement, (ii)
that the Parties may, after consultation with each other, communicate with
employees, customers, suppliers, stockholders, lenders, lessors, and other
particular groups as may be necessary or appropriate and not inconsistent with
the prompt consummation of the transactions contemplated by this Agreement and
(iii) after consultation with each other, as required by law or stock exchange
rule or as necessary for the assertion or enforcement of contractual rights.

      6.6         Confidentiality Agreement.  Lyondell, on behalf of the
Partnership, and Occidental have heretofore entered into the Confidentiality
Agreement relating to the exchange between Lyondell and the Partnership, on the
one hand, and Occidental and the Occidental Partners, on the other hand, of
certain confidential information related or otherwise pertinent to the
transactions contemplated by this Agreement.  Nothing in this Agreement shall
be construed as impairing or otherwise limiting the obligations assumed
pursuant to the Confidentiality Agreement by the parties thereto.  The
Confidentiality Agreement shall remain in full force and effect in accordance
with its terms until the earlier of Closing or its expiration date.  The
Partnership and Millennium shall be bound by, and shall be entitled to the
benefits of, such Confidentiality Agreement to the same extent as if they were
parties thereto.

      6.7         Construction.  In construing this Agreement, the following
principles shall be followed: (i) no consideration shall be given to the
captions of the articles, sections, subsections or clauses, which are inserted
for convenience in locating the provisions of this Agreement and not as an aid
in construction; (ii) no consideration shall be given to the fact or
presumption that any of the Parties had a greater or lesser hand in drafting
this Agreement; (iii) examples shall not be construed to limit, expressly or by
implication, the matter they illustrate; (iv) the word "includes" and its
syntactic variants mean "includes, but is not limited to" and corresponding
syntactic variant expressions; (v) the plural shall be deemed to include the
singular, and vice versa; (vi) each gender shall be deemed to include the other
genders; (vii) each exhibit, appendix, attachment and schedule to this
Agreement is a part of this Agreement; and (viii) any reference herein or in
any schedule hereto to any agreements entered into prior to the date hereof
shall include any amendments or supplements made thereto.

      6.8         Counterparts.  This Agreement may be executed in one or more
counterparts, each of which shall constitute an original, and all of which when
taken together shall constitute one and the same original document.





                                      -25-
   30
      6.9         Governing Law.  The laws of the State of Delaware shall
govern the construction, interpretation and effect of this Agreement without
giving effect to any conflicts of law principles.

      6.10        Transaction Costs.

                  (a)     Subject to subsection (b) and Section 2.8 of the
      Occidental Contribution Agreement, and except as provided on Schedule
      6.10, all reasonable out-of-pocket costs, fees and expenses incurred at
      any time by any Party in connection with the negotiation, execution and
      delivery of this Agreement, the satisfaction of the conditions to Closing
      under this Agreement and the consummation of the transactions
      contemplated hereby shall be reimbursed by the Partnership (if the cost,
      fee or expense was incurred by a Party other than the Partnership) and if
      incurred or reimbursed by the Partnership shall be shared by Lyondell,
      Millennium and Occidental pro rata in accordance with the relative
      interests to be held by their Subsidiaries in the Partnership after
      Closing; provided, however, that if any one expense item or series of
      directly related expenses exceeds $5 million, all of such expense or
      expenses in excess of such $5 million shall be paid by the Party
      incurring such expense.

                  (b)     Notwithstanding the foregoing, each Party shall be
      solely responsible for and bear all of its own respective costs, fees and
      expenses if this Agreement is terminated and the Closing does not occur.

      6.11        Amendment.  All waivers, modifications, amendments or
alterations of this Agreement shall require the written approval of each of the
Parties.  Except as provided in the preceding sentence, no action taken
pursuant to this Agreement, including any investigation by or on behalf of any
Party, shall be deemed to constitute a waiver by the Party taking such action
of compliance with any representations, warranties, covenants or agreements
contained herein and in any documents delivered or to be delivered pursuant to
this Agreement and in connection with the Closing hereunder.  The waiver by any
Party hereto of a breach of any provision of this Agreement shall not operate
or be construed as a waiver of any subsequent breach.

      6.12        Jurisdiction; Consent to Service of Process; Waiver.  ANY
JUDICIAL PROCEEDING BROUGHT AGAINST ANY PARTY TO THIS AGREEMENT OR ANY DISPUTE
UNDER OR ARISING OUT OF OR IN CONNECTION WITH THIS AGREEMENT OR ANY MATTER
RELATED HERETO SHALL BE BROUGHT IN THE FEDERAL OR STATE COURTS OF THE STATE OF
DELAWARE, AND, BY EXECUTION AND DELIVERY OF THIS AGREEMENT, EACH OF THE PARTIES
TO THIS AGREEMENT ACCEPTS THE EXCLUSIVE JURISDICTION OF SUCH COURTS AND
IRREVOCABLY AGREES TO BE BOUND BY ANY JUDGMENT (AS FINALLY ADJUDICATED)
RENDERED THEREBY IN CONNECTION WITH THIS AGREEMENT.  EACH OF THE PARTIES TO
THIS AGREEMENT SHALL APPOINT THE CORPORATION TRUST COMPANY, THE PRENTICE-HALL
CORPORATION SYSTEM, INC.  OR A SIMILAR ENTITY (THE "AGENT") AS AGENT TO RECEIVE
ON ITS BEHALF SERVICE OF PROCESS IN ANY PROCEEDING IN ANY SUCH COURT IN THE
STATE OF DELAWARE, AND EACH OF THE PARTIES TO THIS AGREEMENT SHALL MAINTAIN THE
APPOINTMENT OF SUCH AGENT (OR A SUBSTITUTE AGENT) FROM THE DATE HEREOF UNTIL
THE EARLIER OF THE





                                      -26-
   31
CLOSING DATE OR THE TERMINATION OF THIS AGREEMENT AND SATISFACTION OF ALL
OBLIGATIONS HEREUNDER.  THE FOREGOING CONSENTS TO JURISDICTION AND APPOINTMENTS
OF AGENT TO RECEIVE SERVICE OF PROCESS SHALL NOT CONSTITUTE GENERAL CONSENTS TO
SERVICE OF PROCESS IN THE STATE OF DELAWARE FOR ANY PURPOSE EXCEPT AS PROVIDED
ABOVE AND SHALL NOT BE DEEMED TO CONFER RIGHTS ON ANY PERSON OTHER THAN THE
PARTIES HERETO.  EACH PARTY HEREBY WAIVES ANY OBJECTION IT MAY HAVE BASED ON
LACK OF PERSONAL JURISDICTION, IMPROPER VENUE OR FORUM NON-CONVENIENS.

      6.13        Waiver of Jury Trial.  EACH PARTY HEREBY KNOWINGLY AND
INTENTIONALLY, IRREVOCABLY AND UNCONDITIONALLY WAIVES TRIAL BY JURY IN ANY
LEGAL ACTION OR PROCEEDING RELATING TO THIS AGREEMENT AND FOR ANY COUNTERCLAIM
THEREIN.

      6.14        Action by the Partnership.  Any determination (including as
to the satisfaction of any and all conditions precedent to the obligations of
the Partnership set forth in Section 4.2 of this Agreement), consent, approval,
waiver, other action or right to be made, given, taken or exercised by the
Partnership pursuant to or as contemplated by this Agreement shall be subject
to the Partnership Governance Committee unanimous voting requirements set forth
in Section 6.7 of the Partnership Agreement; provided, however, that the
Partnership's exercise of its right of termination set forth in Section 5.1(b)
of this Agreement shall only require the approval of either two or more
Representatives of Lyondell or two or more Representatives of Millennium,
acting separately.


                            [SIGNATURE PAGES FOLLOW]





                                      -27-
   32
      IN WITNESS WHEREOF, this Master Transaction Agreement has been executed
on behalf of each of the Parties, by their respective officers thereunto duly
authorized, effective as of the date first written above.


                                       EQUISTAR CHEMICALS, LP


                                       By: /s/ Eugene R. Allspach
                                           -------------------------------------
                                           Name:   Eugene R. Allspach
                                           Title:  President and Chief  
                                                   Operating Officer


                                       OCCIDENTAL PETROLEUM CORPORATION


                                       By: /s/ S.P. Dominick, Jr.
                                           -------------------------------------
                                           Name:   S.P. Dominick, Jr.
                                           Title:  Vice President and Controller


                                       LYONDELL PETROCHEMICAL COMPANY


                                       By: /s/ Dan F. Smith
                                           -------------------------------------
                                           Name:     Dan F. Smith
                                           Title:    Chief Executive Officer


                                       MILLENNIUM CHEMICALS INC.


                                       By: /s/ George H. Hempstead, III
                                           -------------------------------------
                                           Name:   George H. Hempstead, III
                                           Title:  Senior Vice President




                [Signature Page to Master Transaction Agreement]





                                      -28-
   33
                                   APPENDIX A
                                       TO
                          MASTER TRANSACTION AGREEMENT


                                  DEFINITIONS

"Affiliate" shall mean any Person that, directly or indirectly through one or
more intermediaries, controls or is controlled by or is under common control
with the Person specified; provided, however, that for purposes of this
Agreement (i) Canadian Occidental Petroleum Ltd. and any entities controlled by
it shall not be considered an Affiliate of the Occidental Group, (ii) Suburban
Propane Partners, L.P. and any entities controlled by it shall not be
considered an Affiliate of the Millennium Group, (iii) neither the Partnership
nor any entity controlled by it shall be considered an Affiliate of the
Occidental Group, the Lyondell Group or the Millennium Group, (iv) no member of
the Occidental Group, the Lyondell Group or the Millennium Group shall be
considered an Affiliate of the Partnership and (v) the Partnership shall not be
considered an Affiliate of any member of the Occidental Group, the Lyondell
Group or the Millennium Group.  For purposes of this definition, the term
"control" shall have the meaning set forth in 17 CFR 230.405, as in effect on
the date hereof.

"Agreement" shall mean this Master Transaction Agreement entered into between
the Parties as of the date hereof.

"Amended and Restated Partnership Agreement" shall mean that certain Amended
and Restated Partnership Agreement of the Partnership to be executed and
delivered at the Closing in substantially the form attached hereto as
Exhibit A.

"Assumed Liabilities" shall have the meaning assigned to such term in the
Occidental Contribution Agreement.

"Authority" shall mean any government or governmental or regulatory body
thereof, or political subdivision thereof, whether federal, state, local or
foreign, or any agency, department or instrumentality thereof, or any court or
arbitrator (public or private).

"Business Day" shall mean any day other than a Saturday, Sunday or other day on
which banks are closed in New York City, New York.

"Code" shall mean the Internal Revenue Code of 1986, as amended.

"Closing" shall have the meaning set forth in the seventh WHEREAS clause of
this Agreement.

"Closing Date" shall have the meaning set forth in Section 1.3.

"Confidentiality Agreement" shall mean that certain Confidentiality Agreement
dated December 11, 1997 between Lyondell and Occidental.





                                      A-1
   34
"Consent" shall mean any consent, waiver, approval, authorization, exemption,
registration, license or declaration of or by any other Person or any
Authority, or any expiration or termination of any applicable waiting period
under any Legal Requirement, required with respect to any Party or any party to
the Related Agreements in connection with (i) the execution and delivery of
this Agreement or any of the Related Agreements or (ii) the consummation of any
of the transactions provided for hereby or thereby.

"Contracts" shall have the meaning assigned to such term in the Occidental
Contribution Agreement.

"Contributed Assets" shall have the meaning assigned to the term "Assets" in
the Occidental Contribution Agreement.

"Encumbrance" shall mean any lien, charge, encumbrance, security interest,
title defect, option or any other restriction or third-party right.

"ERISA" shall mean the Employee Retirement Income Security Act, as amended.

"Exchange Act" shall mean the Securities Exchange Act of 1934, as amended.

"Equistar Group" shall mean the Partnership, the Initial Partners, Lyondell,
Millennium and Millennium Petrochemicals.

"Filing" shall mean any filing with any Person or any Authority required with
respect to any Party in connection with (i) the execution and delivery of this
Agreement or any of the Related Agreements or (ii) the consummation of any of
the transactions provided for hereby or thereby.

"GAAP" shall have the meaning set forth in Section 2.1(e).

"Government License" shall have the meaning assigned to such term in the
Occidental Contribution Agreement.

"Group" shall mean the Equistar Group, the Occidental Group, the Lyondell Group
or the Millennium Group, as appropriate.

"HSR Act" shall mean the Hart-Scott-Rodino Antitrust Improvements Act of 1976,
as amended.

"Initial Master Transaction Agreement" shall mean the Master Transaction
Agreement dated July 25, 1997, between Lyondell and Millennium, as amended.

"Initial Partners" shall mean Lyondell LP, Lyondell GP, Millennium LP and
Millennium GP.

"Joint Proxy Statement" shall mean the Joint Proxy Statement of Lyondell and
Millennium dated October 17, 1997.





                                      A-2
   35
"Knowledge" shall mean with respect to any Party the actual knowledge of (i)
any current plant manager, (ii) any current officer of such Party having
responsibilities with respect to an applicable Subject Business or the
transactions contemplated in this Agreement, (iii) in the case of Occidental,
any current officer of OCC, Oxy Petrochemicals or of an Occidental Partner
having responsibilities with respect to Occidental's Subject Business or the
transactions contemplated in this Agreement, and (iv) any current employee
reporting directly to an officer described in clause (ii) or (iii).

"Legal Requirement" shall mean any law, statute, rule, ordinance, decree,
regulation, requirement, order or judgment of any Authority including the terms
of any Government License.

"Lyondell" shall have the meaning set forth in the first paragraph of this
Agreement.

"Lyondell Asset Contribution Agreement" shall mean that certain Asset
Contribution Agreement dated December 1, 1997, to which Lyondell and the
Partnership are parties.

"Lyondell GP" shall mean Lyondell Petrochemical G.P. Inc., a Delaware
corporation and a wholly owned Subsidiary of Lyondell.

"Lyondell Group" shall mean Lyondell, Lyondell LP and Lyondell GP.

"Lyondell LP" shall mean Lyondell Petrochemical L.P. Inc., a Delaware
corporation and a wholly owned Subsidiary of Lyondell.

"Lyondell Note" shall mean that certain promissory note in the aggregate
principal amount of $345 million dated December 1, 1997 payable to the
Partnership by Lyondell LP.

"Material Adverse Effect" shall mean any adverse circumstance or consequence
that, individually or in the aggregate, has an effect that is material to the
financial condition, results of operations, assets or business of the
applicable Party or Subject Business (taken as a whole), as the case may be.

"Millennium" shall have the meaning set forth in the first paragraph of this
Agreement.

"Millennium Asset Contribution Agreement" shall mean that certain Asset
Contribution Agreement dated December 1, 1997, to which Millennium
Petrochemicals and the Partnership are parties.

"Millennium GP" shall mean Millennium GP LLC, a Delaware limited liability
company and an indirect, wholly owned Subsidiary of Millennium.

"Millennium Group" shall mean Millennium, Millennium Petrochemicals, Millennium
LP and Millennium GP.

"Millennium LP" shall mean Millennium LP LLC, a Delaware limited liability
company and an indirect, wholly owned Subsidiary of Millennium.





                                      A-3
   36
"Millennium Petrochemicals" shall have the meaning set forth in the third
WHEREAS clause of this Agreement.

"Occidental" shall have the meaning set forth in the first paragraph of this
Agreement.

"Occidental Contribution Agreement" shall mean that certain Agreement and Plan
of Merger and Asset Contribution between the Occidental Partners, Oxy
Petrochemicals and the Partnership to be executed and delivered at the Closing
in substantially the form attached hereto as Exhibit B.

"Occidental Assumed Debt" shall mean the Lease Intended for Security, dated
December 18, 1991, among OCC, the institutions listed on Schedule I thereto,
Norwest Bank Minnesota, National Association, as Agent and Chemical Bank and
the Bank of Nova Scotia, as Information Agents, and having an amount
outstanding as of the date of this Agreement of $205 million.

"Occidental Group" shall mean Occidental, OCC, Oxy CH, and the Occidental
Partners and, prior to the Closing, Oxy Petrochemicals.

"Occidental Partners" shall mean PDG Chemical, OCC Sub and Oxy CH Sub.

"OCC" shall have the meaning set forth in the fourth WHEREAS clause of this
Agreement.

"OCC Sub" shall have the meaning set forth in the fourth WHEREAS clause.

"Oxy CH" shall have the meaning set forth in the fourth WHEREAS clause of this
Agreement.

"Oxy CH Sub" shall have the meaning set forth in the fourth WHEREAS clause of
this Agreement.

"Oxy Petrochemicals" shall have the meaning set forth in Section 1.5(d).

"Parties" shall have the meaning set forth in the seventh WHEREAS clause of
this Agreement.

"Partnership" shall have the meaning set forth in the first paragraph of this
Agreement.

"Partnership Agreement" shall mean the Agreement of Limited Partnership of the
Partnership dated October 10, 1997.

"Partnership Governance Committee" shall mean the "Partnership Governance
Committee" as defined in the Partnership Agreement.

"PDG Chemical" shall have the meaning set forth in the fourth WHEREAS clause of
this Agreement.

"Person" shall mean any natural person, corporation, partnership, limited
liability company, joint venture, association, trust or other entity or
organization.





                                      A-4
   37
"Proceeding" shall mean any action, suit, claim or legal, administrative or
arbitration proceeding or governmental investigation to which any Party or an
Affiliate is a party.

"Related Agreements" shall mean the Tier 1 Related Agreements and the Tier 2
Related Agreements.

"Representatives" shall mean the "Representatives," as defined in the
Partnership Agreement.

"SEC" shall mean the Securities and Exchange Commission.

"SEC Reports" shall have the meaning set forth in Section 2.2.(e).

"Securities Act" shall mean the Securities Act of 1933, as amended.

"Stockholders' Meetings" shall mean the special stockholders meetings of each
of Lyondell and Millennium held November 20, 1997.

"Strategic Plan" shall mean the Five-Year Strategic Plan adopted by the
Partnership Governance Committee, as amended and modified prior to the date
hereof pursuant to action of the Partnership Governance Committee, as set forth
in minutes of their meetings.

"Subject Business" shall mean (i) in the case of Occidental, the "Contributed
Business" as defined in the Occidental Contribution Agreement, including the
Contributed Assets and the Assumed Liabilities related thereto; (ii) in the
case of each of Lyondell and Millennium, their respective "Contributed
Businesses" as defined in their respective Asset Contribution Agreements dated
December 1, 1997; and (iii) in the case of the Partnership, the business of the
Partnership, which consists substantially of the Subject Business of Lyondell
and Millennium.

"Subsidiary" shall mean, with respect to any Party, any Person of which such
Party, either directly or indirectly, owns 50% or more of the equity or voting
interests, except, in the case of Lyondell, Lyondell-CITGO Refining Company
Ltd. and Equistar Chemicals, LP.

"Tier 1 Related Agreements" shall mean those agreements so designated on
Appendix B, forms of each of which (including forms of the exhibits and certain
of the schedules thereto current as of the dates indicated therein), are
attached hereto as Exhibits.

"Tier 2 Related Agreements" shall mean those agreements so designated on
Appendix B (including Appendix B-2), descriptions of certain terms of which are
included thereon.

"Unit" shall mean a unit representing a partnership interest in the
Partnership.





                                      A-5
   38
                                   APPENDIX B
                                       TO
                          MASTER TRANSACTION AGREEMENT


                           LIST OF RELATED AGREEMENTS


Tier 1 Related Agreements

      1.          Amended and Restated Agreement of Limited Partnership

      2.          Agreement and Plan of Merger and Asset Contribution among the
                  Occidental Partners, Oxy Petrochemicals and the Partnership

      3.          Amended and Restated Parent Agreement

      4.          Sales Agreement (Ethylene)


Tier 2 Related Agreements

      1.          Agreements the form of which is an exhibit to the Occidental
                  Agreement and Plan of Merger and Contribution.

      2.          Operating Agreement by and between the Partnership and OCC.

      3.          Tolling Processing Agreement by and between the Partnership
                  and OCC.

      4.          Amended and Restated Indemnity Agreement among OCC, PDG
                  Chemical, Oxy Petrochemicals, OCC Sub, Oxy CH Sub, Lyondell
                  GP, Lyondell LP, Millennium GP, Millennium LP and Millennium
                  America Inc., a Delaware corporation,  amending and restating
                  the Indemnity Agreement, dated December 1, 1997.

      5.          Agreement between OCC and the Partnership obligating OCC to
                  provide a guarantee for the collection of $419,700,000 of
                  Partnership debt and obligating the Partnership to extend or
                  refinance such debt for a term at least equivalent to the
                  term of such guarantee.

      6.          Agreement between OCC and the Partnership obligating the
                  Partnership to prepay or restructure the Occidental Assumed
                  Debt within an agreed period of time.

      7.          Promissory Note for $419,700,000 of the Partnership payable
                  to Oxy CH Sub.

      8.          Promissory Note for $75 million of the Partnership payable to
                  Millennium LP.





                                      B-1
   39
      9.          Agreement for Assumption of Lease Intended for Security dated
                  December 18, 1991 ($205 million).

      10.         Assignment and Assumption Agreement related to Lease Intended
                  for Security dated March 28,1994 (Pitney Bowes).

      11.         Agreement  regarding termination of Lyondell guaranty of
                  certain Partnership railcar leases.

      12.         Sublease by OCC to the Partnership related to 1990 railcar
                  lease.

      13.         Sublease by Oxy Petrochemicals to the Partnership related to
                  1995 railcar lease.

      14.         Tax Indemnity Agreement between OCC and the Partnership
                  related to the 1990 railcar sublease.

      15.         Tax Indemnity Agreement  between Oxy Petrochemicals and the
                  Partnership related to the 1995 railcar sublease.

      16.         Master Arbitration Amendment to Related Agreements.

      17.         First Amendment to Lyondell Asset Contribution Agreement.

      18.         First Amendment to Millennium Asset Contribution Agreement.

      19.         Transition Services Agreement between the Partnership and
                  OCC.

      20.         Pipeline Acquisition Agreement between OCC and the
                  Partnership related to the Cyclohexane pipeline.





                                      B-2