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Exhibit 10.23(d)
Amendments dated December 10, 1998 and January 23, 1998 to the Millennium
Chemicals Inc. Long Term Stock Incentive Plan

                             AMENDMENT NUMBER THREE
                                     TO THE
                            MILLENNIUM CHEMICALS INC.
                         LONG TERM STOCK INCENTIVE PLAN

               WHEREAS, Millennium Chemicals Inc. (the "Company") maintains the
Millennium Chemicals Inc. Long Term Stock Incentive Plan (the "Plan"); and

               WHEREAS, pursuant to Article XIV of the Plan, the Board of
Directors of the Company (the "Board") has the right to amend the Plan; and

               WHEREAS, the Board desires to amend the Plan;

               NOW, THEREFORE, effective as of December 10, 1998, the Plan is
amended as follows:

               1.     Subsection 13.2(a) of the Plan is amended by deleting the
                      word "owner" in the one place it appears in such
                      subsection and substituting " `beneficial owner'" in lieu
                      thereof.

               2.     Subsection 13.2(d) is amended and restated to read as
                      follows:


                 the stockholders of the Company approve a plan of complete
liquidation of the Company or the closing of the sale or disposition by the
Company of all or substantially all of the Company's assets other than the sale
or disposition of all or substantially all of the assets of the Company to one
or more Subsidiaries (as defined below) of the Company or to a person or persons
who beneficially own, directly or indirectly, at least fifty percent (50%) or
more of the combined voting power of the outstanding voting securities of the
Company at the time of the sale or disposition. "Subsidiary" shall have the
meaning set forth in Section 424 of the Code and the term shall also include any
partnership, limited liability company or other business entity if the Company
owns, directly or indirectly, securities or other ownership interests
representing at least fifty percent (50%) of the ordinary voting power or equity
or capital interests of such entity. Notwithstanding any of the foregoing, the
formation of Equistar Chemicals, LP ("Equistar") and the contribution of assets
by Millennium Petrochemicals Inc. to Equistar on December 1, 1997 shall not
constitute a Change in Control, and the sale or disposition of all or any part
of the Company's interests in Equistar shall not constitute a Change in Control.

               3.     In all other respects, the Plan is hereby ratified and
                      confirmed.

               IN WITNESS WHEREOF, this amendment has been executed as of the
10th day of December, 1998.

                                                   MILLENNIUM CHEMICALS INC.


                                                   By:  ______________________



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                                    AMENDMENT
                                     TO THE
                            MILLENNIUM CHEMICALS INC.
                         LONG TERM STOCK INCENTIVE PLAN


               WHEREAS, Millennium Chemicals Inc. (the "Company") maintains the
Millennium Chemicals Inc. Long Term Stock Incentive Plan (the "Plan"); and

               WHEREAS, pursuant to Article XIV of the Plan, the Board of
Directors of the Company (the "Board") has the right to amend the Plan; and

               WHEREAS, the Board desires to amend the Plan;

               NOW, THEREFORE, effective as of January 23, 1998, the Plan is
amended as follows:

               1. Subsection 11.1(a)(ii) and Subsection 11.1(a)(iii) of the Plan
are amended by (a) deleting the number "$15,000" in each place it appears and
(b) substituting the following in lieu thereof: "one-third of the annual
directors' retainer fee (as in effect on such date.)"

               2. In all other respects, the Plan is hereby ratified and
confirmed.

               IN WITNESS WHEREOF, this amendment has been executed the 23rd day
of January, 1998.


                                                   MILLENNIUM CHEMICALS INC.


                                                   By:________________________




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