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                                                                EXHIBIT 10.27(b)

          SECOND AMENDMENT TO MILLENNIUM ASSET CONTRIBUTION AGREEMENT

     This Second Amendment to Millennium Asset Contribution Agreement (this
"Second Amendment"), dated as of September 30, 2001, is entered into by and
among Millennium Petrochemicals Inc., a Virginia corporation (the
"Contributor"), Millennium Petrochemicals LP LLC, a Delaware limited liability
company (the "Contributing Partner") and Equistar Chemicals, LP, a Delaware
limited partnership (the "Partnership").

                                   RECITALS:

     A.  The Contributor, the Contributing Partner and the Partnership are
parties to that certain Asset Contribution Agreement, dated as of December 1,
1997, as amended by that certain First Amendment to Millennium Asset
Contribution Agreement, dated as of May 15, 1998 (such agreement, as amended by
the First Amendment, herein called the "Asset Contribution Agreement").

     B.  Following execution of the Asset Contribution Agreement, the
Contributor, the Contributing Partner and the Partnership (the "Parties" and
each individually, a "Party") have agreed to certain amendments clarifying the
treatment of, and procedures pertaining to the management of, certain claims
arising under the Asset Contribution Agreement.

     C.  Simultaneously, and as an integral part of the resolution of the
matters referenced herein, (i) the Partnership and certain affiliates of
Occidental Petroleum Corporation have agreed to make certain amendments pursuant
to that certain First Amendment to Occidental Asset Contribution Agreement dated
as of September 30, 2001 (the "Occidental First Amendment") and (ii) the
Partnership and certain affiliates of Lyondell Chemical Company have agreed to
settle certain claims and make certain amendments pursuant to that certain
Second Amendment to Lyondell Asset Contribution Agreement dated as of September
30, 2001 (the "Lyondell Second Amendment").

     D.  Accordingly, the Parties desire to amend the Asset Contribution
Agreement on the terms set forth herein.  Capitalized terms used and not
otherwise defined herein shall have the meanings given such terms in the Asset
Contribution Agreement.  All section references in this Second Amendment are
intended to refer to provisions contained in the Asset Contribution Agreement.

     NOW THEREFORE, in consideration of the premises and of the mutual covenants
of the Parties hereto, it is hereby agreed  that the Asset Contribution
Agreement is hereby amended as follows:

     Section 1.  Seven Year PCCL Claims.  In settlement of a dispute concerning
treatment of certain claims under the Asset Contribution Agreement, the Parties
hereby agree that the liabilities set forth on Exhibit A, in the amounts
specified therein, shall be deemed to be Seven Year PCCL Claims and such claims
shall thereby be fully and finally resolved.

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     Section 2.  Assumption of Liabilities.

     (a) Section 2.5(a)(vi) is hereby amended and restated as follows:

          (vi)   Third Party Claims (including De Minimis Claims) that are
     related to Pre-Closing Contingent Liabilities and that are first asserted
     seven years or more after the Closing Date.

     (b) The word "and" is hereby deleted from the end of Section 2.5(a)(x) and
added to the end of Section 2.5(a)(xi).

     (c) A new Section 2.5(a)(xii) is hereby added as follows:

          (xii)  Pre-Closing Contingent Liabilities that do not involve a Third
     Party Claim and De Minimis Claims first asserted against the Partnership
     (and not the Contributor) within seven years after the Closing Date.

     Section 3.  Excluded Liabilities.  Section 2.6(i) is hereby amended and
restated as follows:

          (i)    Any Pre-Closing Contingent Liability that is not an Assumed
     Liability, including any De Minimis Claim that is first asserted against
     Contributor and the Partnership, jointly, within seven years after the
     Closing Date.

     Section 4.  Lowest Cost Response.  The definition of "Lowest Cost Response"
is hereby amended to delete the phrase "Chemical Substances" in the first
sentence and replace it with the word "condition."

     Section 5.  Effectiveness of this Second Amendment.  This Second Amendment
shall be effective from and after the date hereof except as specifically
provided in Section 1 hereof; provided, however, that the execution and delivery
of the Occidental First Amendment and the Lyondell Second Amendment shall be
conditions to the effectiveness of this Second Amendment.  Except as amended by
this Second Amendment, all of the terms and provisions of the Asset Contribution
Agreement shall remain in full force and effect among the Parties from and after
the date hereof.

     Section 6.  Counterparts.  This Second Amendment may be executed in any
number of counterparts, each of which shall be deemed an original and all of
which together shall be deemed one and the same instrument.

     Section 7.  APPLICABLE LAW.  THIS SECOND AMENDMENT SHALL BE GOVERNED BY,
AND CONTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF DELAWARE EXCLUDING
CONFLICTS OF LAW PRINCIPLES OF SUCH

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JURISDICTION, EXCEPT TO THE EXTENT SUCH MATTERS ARE MANDATORILY SUBJECT TO THE
LAWS OF ANOTHER JURISDICTION PURSUANT TO THE LAWS OF SUCH OTHER JURISDICTION.

                  [Remainder of Page Intentionally Left Blank]

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     IN WITNESS WHEREOF, the Parties have executed and delivered this Second
Amendment as of the date first above written.

                              MILLENNIUM PETROCHEMICALS INC.,
                              a Virginia corporation.

                              By: /s/ C. William Carmean
                                 ------------------------------------------
                              Name:   C. William Carmean
                              Title:  Vice President-Legal

                              MILLENNIUM PETROCHEMICALS LP LLC,
                              a Delaware limited liability company

                              By: /s/ C. William Carmean
                                 ------------------------------------------
                              Name:   C. William Carmean
                              Title:  Vice President-Legal

                              EQUISTAR CHEMICALS, LP,
                              a Delaware limited partnership

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

[Signature Page to Second Amendment To Millennium Asset Contribution Agreement]

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                                   EXHIBIT A

                             SEVEN YEAR PCCL CLAIMS

The following Claims made by Equistar against Millennium shall be included as
Seven Year PCCL Claims for an aggregate amount of $1,757,131:

1.   Due diligence items from asset sale at Heath.
2.   Old waste oil sump at Heath.
3.   Due diligence items from asset sale at Crockett.
4.   Pellet and powder controls at La Porte.
5.   AB compressor controls at La Porte.
6.   Self-closing gates at La Porte.
7.   Quench tower relief project at La Porte.
8.   AB2/AB3 compliance projects at La Porte.
9.   Complex-wide emergency alarm and radio at La Porte.
10.  S-1 feed alternative heat (Petro FBO modifications) at La Porte.
11.  Plant alarm replacement at La Porte.
12.  VOM emission controls and Ohio permits at Fairport Harbor.

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                                                                EXHIBIT 10.29(a)

           FIRST AMENDMENT TO OCCIDENTAL ASSET CONTRIBUTION AGREEMENT

     This First Amendment to Occidental Asset Contribution Agreement (this
"First Amendment"), dated as of September 30, 2001, is entered into by and among
Occidental Petrochem Partner 1, Inc., a Delaware corporation, Occidental
Petrochem Partner 2, Inc., a Delaware corporation, PDG Chemical Inc., a Delaware
corporation, Occidental Petrochem Partner GP, Inc., a Delaware corporation ("New
GP"; collectively, with the other preceding entities the "Oxy Partners"), and
Equistar Chemicals, LP, a Delaware limited partnership (the "Partnership").

                                   RECITALS:

     A.  Certain of the Oxy Partners and the Partnership were among the parties
to that certain Agreement and Plan of Merger and Asset Contribution, dated as of
May 15, 1998, (the "Asset Contribution Agreement"), together with Oxy
Petrochemicals Inc., a Delaware corporation ("OPI"), also an affiliate of
Occidental Petroleum Corporation ("Occidental").  Pursuant to the terms of the
Asset Contribution Agreement, OPI merged into the Partnership on the Closing
Date and ceased to exist thereafter.

     B.  Concurrently with the execution and delivery of the Asset Contribution
Agreement, certain affiliates of Occidental, Lyondell Chemical Company
("Lyondell") and Millennium Petrochemicals Inc. ("Millennium") entered into that
certain Amended and Restated Partnership Agreement of Equistar Chemicals, LP
dated May 15, 1998 (the "Partnership Agreement").  Subsequently, the partners of
the Partnership agreed to enter into that certain First Amendment to Amended and
Restated Limited Partnership Agreement of Equistar Chemicals, LP, dated as of
June 30, 1998 (the "Amendment"), to the Partnership Agreement.  Pursuant to the
Amendment, Occidental effected a reorganization of its interests in the
Partnership, including, among other things, a transfer of the remaining GP
interest of PDG to New GP, which is a successor to PDG and any interest of PDG
in and to the Partnership.

     C.  Recently, the Oxy Partners and the Partnership (collectively, the
"Parties" and each individually, a "Party") have agreed to certain amendments
clarifying the treatment of, and procedures pertaining to the management of,
certain claims that may arise under the Asset Contribution Agreement.
Simultaneously, and as an integral part of the resolution of the matters
referenced herein, (i) the Partnership and certain affiliates of Millennium have
agreed to settle certain claims and make certain amendments pursuant to that
certain Second Amendment to Millennium Asset Contribution Agreement dated as of
September 30, 2001 (the "Millennium Second Amendment") and (ii) the Partnership
and certain affiliates of Lyondell have agreed to settle certain claims and make
certain amendments pursuant to that certain Second Amendment to Lyondell Asset
Contribution Agreement dated as of September 30, 2001 (the "Lyondell Second
Amendment").

     D.  Accordingly, the Parties desire to amend the Asset Contribution
Agreement on the terms set forth herein.  Capitalized terms used and not
otherwise defined herein shall have the

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meanings given such terms in the Asset Contribution Agreement. All section
references in this First Amendment are intended to refer to provisions contained
in the Asset Contribution Agreement.

     NOW THEREFORE, in consideration of the premises and of the mutual covenants
of the Parties hereto, it is hereby agreed  that the Asset Contribution
Agreement is hereby amended as follows:

     Section 1.  Assumption of Liabilities.

     (a) Section 2.5(a)(vi) is hereby amended and restated as follows:

          (vi)   Third Party Claims (including De Minimis Claims) that are
     related to Pre-Closing Contingent Liabilities and that are first asserted
     seven years or more after the Closing Date.

     (b) The word "and" is hereby deleted from the end of Section 2.5(a)(x) and
added to the end of Section 2.5(a)(xi).

     (c) A new Section 2.5(a)(xii) is hereby added as follows:

          (xii)  Pre-Closing Contingent Liabilities that do not involve a Third
     Party Claim and De Minimis Claims first asserted against the Partnership
     (and not the Contributor) within seven years after the Closing Date.

     Section 2.  Excluded Liabilities.  Section 2.6(i) is hereby amended and
restated as follows:

          (i)    Any Pre-Closing Contingent Liability that is not an Assumed
     Liability, including any De Minimis Claim that is first asserted against
     Contributor and the Partnership, jointly, within seven years after the
     Closing Date.

     Section 3.  Lowest Cost Response.  The definition of "Lowest Cost Response"
is hereby amended to delete the phrase "Chemical Substances" in the first
sentence and replace it with the word "condition."

     Section 4.  Effectiveness of this First Amendment.  This First Amendment
shall be effective from and after the date hereof, except as expressly provided
with respect to certain disputes described in the Millennium Second Amendment;
provided, however, that the execution and delivery of the Millennium Second
Amendment and the Lyondell Second Amendment shall be conditions to the
effectiveness of this First Amendment.  Except as expressly amended by this
First Amendment, all of the terms and provisions of the Asset Contribution
Agreement shall remain in full force and effect among the Parties from and after
the date hereof.

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     Section 5.  Counterparts.  This First Amendment may be executed in any
number of counterparts, each of which shall be deemed an original and all of
which together shall be deemed one and the same instrument.

     Section 6.  APPLICABLE LAW.  THIS FIRST AMENDMENT SHALL BE GOVERNED BY, AND
CONTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF DELAWARE EXCLUDING
CONFLICTS OF LAW PRINCIPLES OF SUCH JURISDICTION, EXCEPT TO THE EXTENT SUCH
MATTERS ARE MANDATORILY SUBJECT TO THE LAWS OF ANOTHER JURISDICTION PURSUANT TO
THE LAWS OF SUCH OTHER JURISDICTION.

                  [Remainder of Page Intentionally Left Blank]

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     IN WITNESS WHEREOF, the Parties have executed and delivered this First
Amendment as of the date first above written.

                              OCCIDENTAL PETROCHEM PARTNER 1, INC.,
                              a Delaware corporation

                              By: /s/ Linda S. Peterson
                                 ----------------------------------------
                              Name: Linda S. Peterson
                              Title: Vice President and Secretary

                              OCCIDENTAL PETROCHEM PARTNER 2, INC.,
                              a Delaware corporation

                              By: /s/ Linda S. Peterson
                                 ----------------------------------------
                              Name: Linda S. Peterson
                              Title: Vice President and Secretary

                              OCCIDENTAL PETROCHEM PARTNER GP, INC.,
                              a Delaware corporation

                              By: /s/ Linda S. Peterson
                                 ----------------------------------------
                              Name: Linda S. Peterson
                              Title: Vice President and Assistant Secretary

                              PDG CHEMICAL INC.,
                              a Delaware corporation

                              By: /s/ Linda S. Peterson
                                 ----------------------------------------
                              Name: Linda S. Peterson
                              Title: Vice President and Assistant Secretary

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                              EQUISTAR CHEMICALS, LP,
                              a Delaware limited partnership

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

 [Signature Page to First Amendment To Occidental Asset Contribution Agreement]

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