<PAGE>

                                                       EXHIBIT 10.14(c)
                                                         EXECUTION COPY
                    SECOND AMENDMENT dated as of October 29, 1997 (this
               "Amendment"), to the credit Agreement dated as of July 26, 1996,
               as amended by the Amendment dated as of December 18, 1996 and as
               further amended, supplemented or otherwise modified from time to
               time (the "Credit Agreement"), among MILLENNIUM AMERICA INC.
               (formerly HANSON AMERICA INC.), a Delaware corporation referred
               to as "HAI" under the Credit Agreement ("Millennium America")'
               MILLENNIUM CHEMICALS INC., a Delaware corporation
               ("Millennium"), as Guarantor; the lenders from time to time
               party thereto, initially consisting of those listed on Schedule
               2.01 to the Credit Agreement (the "Lenders"); THE CHASE
               MANHATTAN BANK, as Documentation Agent; and BANK OF AMERICA
               NATIONAL TRUST AND SAVINGS ASSOCIATION, as administrative agent
               (in such capacity, the "Administrative Agent").

          A. The parties hereto have agreed, subject to the terms and conditions
hereof, to amend the Credit Agreement on the terms and subject to the conditions
provided herein.

          B. Capitalized terms used and not otherwise defined herein shall have
the meanings assigned to such terms in the Credit Agreement.

          SECTION 1. Proposed Joint Venture of Millennium and Lyondell
Petrochemical Company.

          Reference is made to the agreement by Millennium and Lyondell
     Petrochemical Company ("Lyondell") to combine certain of their respective
     petrochemical businesses to form a joint venture, which will be named
     Equistar Chemicals, LP ("Equistar" or the "Joint Venture"). The Lenders
     hereby waive the provisions of Section 6.06 of the Credit Agreement to the
     extent (and only to the extent) necessary to permit consummation of the
     Joint Venture on terms and in a manner not materially inconsistent with the
     Master Transaction Agreement, dated as of July 25, 1997, between Lyondell
     and Millennium, as amended by the First Amendment thereto dated as of
     October 10, 1997 and as further amended, supplemented or otherwise modified
     from time to time (the "Master Transaction Agreement"), and the
     description thereof in the Joint Proxy Statement filed by Lyondell and
     Millennium with the Securities and Exchange Commission on October 17, 1997
     (the "Joint Proxy Statement"), including transfer by Millennium
     Petrochemicals Inc., a wholly owned Subsidiary of



<PAGE>


                                                                            2

     Millennium America, to the Joint Venture of substantially all of the assets
     comprising Millennium's polyethylene and related products, performance
     polymers and ethyl alcohol businesses (other than accounts receivable
     relating to products sold before the closing of the Joint Venture) in
     exchange for a 43% interest in the Joint Venture, the assumption and
     repayment of Indebtedness of Millennium in the amount of $750,000,000 and
     the Joint Venture's assumption of certain other liabilities.

          SECTION 2. Notice of Reduction of Total Commitment.

          (a) Pursuant to Section 2.10(b) of the Credit Agreement, effective as
     of the closing of the Joint Venture and Pursuant to Section 8 of this
     Amendment, the Total Commitment under the Credit Agreement will
     automatically be reduced by an aggregate principal amount of $750,000,000.
     Millennium shall pay to the Administrative Agent for the account of the
     Lenders, on the date of such reduction, the Facility Fee on the amount of
     the Standby Commitments so reduced that has accrued through the date of
     such reduction. For purposes of the reduction described in this clause (a),
     each Lender hereby waives the notice requirement specified in Section
     2.10(b) of the Credit Agreement and agrees that this Amendment shall serve
     as prior irrevocable written notice of such reduction.

          (b) Not more than 90 days after the closing of the Joint Venture and
     pursuant to Section 8 of this Amendment, Millennium will further
     automatically reduce the Total Commitment under Section 2.10(b) of the
     Credit Agreement by and additional $250,000,000. Millennium shall pay to
     the Administrative Agent for the account of the Lenders, on the date of
     such reduction, the Facility Fee on the amount of the Standby Commitments
     so reduced that  has accrued through the date of such reduction.
     For purposes of the reduction described in this clause (b), each
     Lender hereby waives the notice requirement specified in Section
     2.10(b) of the Credit Agreement and agrees that this Amendment shall
     serve as prior irrevocable written notice of such reduction.

          SECTION 3. Amendment to Section 1.01. Section 1.01 of the Credit
Agreement is hereby amended by adding the following defined terms in the
appropriate alphabetical order:


<PAGE>



                                                                               3


          (a) "Equistar" shall mean Equistar Chemicals, LP, a Delaware limited
     partnership.

          (b) "Joint Proxy Statement" shall mean the Joint Proxy Statement
     filed by Lyondell and Millennium with the Securities and Exchange
     Commission on October 17, 1997.

          (c) "Joint Venture" shall mean the combination of certain of
     Lyondell's and Millennium's respective petrochemicals businesses to form a
     joint venture, which will be organized as a Delaware limited partnership,
     named Equistar Chemicals, LP and headquartered in Houston, Texas, all on
     terms and in a manner not materially inconsistent with the Master
     Transaction Agreement and the description thereof in the Joint Proxy
     Statement.

          (d) "Limited Partnership Agreement" shall mean the Limited
     Partnership Agreement dated as of October 10, 1997, as amended,
     supplemented or otherwise modified from time to time, by and among
     Equistar, Lyondell GP, Millennium GP, Lyondell LP and Millennium LP.

          (e) "Lyondell" shall mean Lyondell Petrochemical Company, a Delaware
     corporation and a partner in the Joint Venture.

          (f) "Lyondell GP" shall mean Lyondell Petrochemical G.P., Inc. the
     wholly owned subsidiary of Lyondell that serves as one of the general
     partners of the Joint Venture.

          (g) "Lyondell LP" shall mean Lyondell Petrochemical L.P. Inc., the
     wholly owned subsidiary of Lyondell that serves as one of the limited
     partners of the Joint Venture.

          (h) "Master Transaction Agreement" shall mean the Master Transaction
     Agreement dated as of July 25, 1997, as amended by the First Amendment
     thereto dated as of October 10, 1997 and as further amended, supplemented
     or otherwise modified from time to time, between Lyondell and Millennium
     pursuant to which Lyondell and Millennium have agreed to form the Joint
     Venture.

          (i) "Millennium GP" shall mean Millennium Petrochemicals GP LLC, the
     indirect, wholly owned Subsidiary of Millennium America that serves as one
     of the general partners of the Joint Venture.



<PAGE>



                                                                               4


          (j) "Millennium LP" shall mean Millennium Petrochemicals LP LLC, the
     indirect, wholly owned Subsidiary of Millennium America that serves as one
     of the limited partners of the Joint Venture.

          SECTION 4. Amendment to Section 6.01. Section 6.01 of the Credit
Agreement is hereby amended by:

          (a) deleting the word "and" at the end of paragraph (o);

          (b) deleting the period at the end of paragraph (p) and substituting
     in lieu thereof "; and"; and

          (c) adding thereto a new clause (q) that reads in its entirety as
     follows:

          "(q) Liens, if any, that are deemed to exist pursuant to any first
     offer obligation of Millennium or right of first refusal of Lyondell as
     provided for in the Limited Partnership Agreement;"

          SECTION 5. Amendment to Section 6.03. Section 6.03 of the Credit
Agreement is hereby amended by:

          (a) deleting the word "and" at the end of paragraph (e) and
     substituting in lieu thereof ";"; and

          (b) adding thereto a new clause (g) that reads in its entirety as
     follows:

               "and (g) Indebtedness that is deemed to constitute Indebtedness
          of Millennium GP so long as Millennium GP engages in no business and
          owns no asset other than (i) those that constitute the business,
          partnership interests and assets of the Joint Venture and (ii)
          intercompany notes in an amount not to exceed $50,000,000 issued by
          Millennium or one of its Affiliates to Millennium GP for the purpose
          of capitalizing Millennium GP."


<PAGE>



                                                                               5


          SECTION 6. Amendment to Section 6.07. Section 6.07 of the Credit
Agreement is hereby amended by adding to the end of Section 6.07 a new sentence
that reads in its entirety:

          "Notwithstanding any of the foregoing, (i) nothing in this Section
     shall limit the completion of the Joint Venture in accordance with
     applicable law and on terms and in a manner not materially inconsistent
     with the Master Transaction Agreement and the description thereof in the
     Joint Proxy Statement and (ii) for purposes of this Section 6.07 only,
     Equistar shall not be considered an Affiliate of Millennium.

          SECTION 7. Representation and Warranties. Millennium America and
Millennium hereby represent and warrant to the Lenders and the Administrative
Agent that on and as of the date hereof, and after giving effect to this
Amendment:

          (a) This Amendment has been duly executed and delivered by Millennium
     America and Millennium and constitutes a legal, valid and binding
     obligation of Millennium America and Millennium enforceable against
     Millennium America and Millennium in accordance with its terms.

          (b) The representation and warranties of Millennium America or
     Millennium, as the case may be, contained in the Credit Agreement and any
     other Loan Documents are true and correct in all material respects.

          (c) No default or Event of Default has occurred and is continuing.

          SECTION 8. Conditions to Effectiveness. This Amendment shall become
effective when the following conditions have been satisfied:

          (a) The Administrative Agents shall have received duly executed
     counterparts of this Amendment which, when taken together, bear the
     authorized signatures of each of the parties hereto.

          (b) The closing of the Joint Venture, and the transfer of assets by
     Millennium and Lyondell, shall have occurred or shall simultaneously occur
     in accordance with applicable law and on terms and in a manner not
     materially inconsistent with the Master


<PAGE>


                                                                               6


     Transaction Agreement and the description thereof in the Joint Proxy
     Statement:

         (c) All conditions precedent to the effectiveness of the $1,250,000,000
     Credit Agreement, by and among Equistar, the lenders party thereto and Bank
     of America National Trust and Savings Association and The Chase Manhattan
     Bank, as Administrative Agents (other than the effectiveness of this
     Amendment) shall have been satisfied or waived by the lenders party thereto
     and the initial funding under such credit facility shall have occurred or
     shall simultaneously occur.

          SECTION 9. Effect of Amendment. Except as expressly set forth herein,
this Amendment shall not by implication or otherwise limit, impair, constitute a
waiver of, or otherwise affect the rights and remedies of the Lenders under the
Credit Agreement or any other Loan Document, and shall not alter, modify, amend
or in any way affect any of the terms, conditions, obligations, covenants or
agreements contained in the Credit Agreement or any other Loan Document, all of
which are ratified and affirmed in all respects and shall continue in full force
and effect. Nothing herein shall be deemed to entitle Millennium America or
Millennium to a consent to, or a waiver, amendment, modification or other change
of, any of the terms, conditions, obligations, covenants or agreements contained
in the Credit Agreement or any other Loan Document in similar or different
circumstances. This Amendment shall apply and be effective only with respect to
the provisions of the Credit Agreement specifically referred to herein.

          SECTION 10. Counterparts. This Amendment may be signed in any number
of counterparts, each of which shall constitute an original but all of which
when taken together shall constitute but one contract. Delivery of an executed
counterpart of a signature page by facsimile transmission shall be effective as
delivery of a manually executed counterpart of this Amendment.

          SECTION 11. APPLICABLE LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

          SECTION 12. Credit Agreement. Except as expressly amended hereby, the
Credit Agreement shall continue in full force and effect in accordance with the
provisions thereof. As used in the Credit Agreement, the terms "Agreement",
"herein", "hereinafter", "hereunder", "hereto", and words of similar import
shall mean, from and



<PAGE>



                                                                               7

after the date hereof, the Credit Agreement as amended by this Amendment.

          SECTION 13. Expenses. Millennium America (and Millennium, as
Guarantor) shall pay all reasonable out-of-pocket expenses incurred by the
Administrative Agent or any of it Affiliates in connection with the preparation,
negotiation, execution, delivery and enforcement of this Amendment, including,
but not limited to, the reasonable fees and disbursements of Cravath, Swaine &
Moore.


<PAGE>




                                                                               8


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

                                            MILLENNIUM AMERICA INC.,

                                              by  CHRISTINE WUBBOLDING
                                                --------------------------------
                                                Name: CHRISTINE WUBBOLDING
                                                Title: VP & TREASURER

                                            MILLENNIUM CHEMICALS INC.,

                                              by  CHRISTINE WUBBOLDING
                                                --------------------------------
                                                Name: CHRISTINE WUBBOLDING
                                                Title: VP & TREASURER

                                            BANK OF AMERICA NATIONAL TRUST AND
                                            SAVINGS ASSOCIATION, individually
                                            and as Administrative Agent,

                                              by
                                                --------------------------------
                                                Name:
                                                Title:

                                            THE CHASE MANHATTAN BANK,
                                            individually and as Documentation
                                            Agent,

                                              by
                                                --------------------------------
                                                Name:
                                                Title:





<PAGE>


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


                                            MILLENNIUM AMERICA INC.,

                                              by
                                                --------------------------------
                                                Name:
                                                Title:

                                            MILLENNIUM CHEMICALS INC.,

                                              by
                                                --------------------------------
                                                Name:
                                                Title:

                                            BANK OF AMERICA NATIONAL TRUST AND
                                            SAVINGS ASSOCIATION, individually
                                            and as Administrative Agent,

                                              by /s/ Steve A. Aronowitz
                                                --------------------------------
                                                Name: STEVE A. ARONOWITZ
                                                Title: MANAGING DIRECTOR

                                            THE CHASE MANHATTAN BANK,
                                            individually and as Documentation
                                            Agent,

                                              by /s/ Mary Elisabeth Swerz
                                                --------------------------------
                                                Name: Mary Elisabeth Swerz
                                                Title: Vice President



<PAGE>



                                                                               9


                                       ABN AMRO BANK N.V. NEW YORK BRANCH,

                                         by  George M. Dugan
                                           ---------------------------------
                                           Name: GEORGE M. DUGAN
                                           Title: VICE PRESIDENT

                                         by  DAVID A. MANDELL
                                           ---------------------------------
                                           Name: DAVID A. MANDELL
                                           Title: GROUP VICE PRESIDENT

                                       BANK BRUSSELS LAMBERT, NEW YORK BRANCH,

                                         by
                                         -------------------------------------
                                           Name:
                                           Title:

                                         by
                                         -------------------------------------
                                           Name:
                                           Title:

                                       THE BANK OF NEW YORK,

                                         by
                                         -------------------------------------
                                           Name:
                                           Title:

                                       BANK OF TOKYO-MITSUBISHI TRUST COMPANY,

                                         by
                                         -------------------------------------
                                           Name:
                                           Title:




<PAGE>




                                                                              10


                                        BANQUE NATIONALE DE PARIS,

                                          by
                                          -------------------------------------
                                            Name:
                                            Title:

                                          by
                                          -------------------------------------
                                            Name:
                                            Title:

                                        BANQUE PARIBAS,

                                          by
                                          -------------------------------------
                                            Name:
                                            Title:

                                        BARCLAYS BANK PLC,

                                          by
                                          -------------------------------------
                                            Name:
                                            Title:

                                        CIBC INC.,

                                          by
                                          -------------------------------------
                                            Name:
                                            Title:

                                        CITIBANK, N.A.,

                                          by
                                          -------------------------------------
                                            Name:
                                            Title:




<PAGE>



                                                                              11


                                        COMMERZBANK AG, NEW YORK AND/OR
                                        GRAND CAYMAN BRANCHES,

                                          by ROBERT DONOHUE
                                            ----------------------------------
                                            Name: ROBERT DONOHUE
                                            Title: VICE PRESIDENT

                                          by PETER DOYLE
                                            ----------------------------------
                                          Name: PETER DOYLE
                                          Title: ASSISTANT TREASURER

                                        CREDIT LYONNAIS NEW YORK BRANCH,

                                          by
                                            ----------------------------------
                                          Name:
                                          Title:

                                        CREDIT LYONNAIS UNITED KINGDOM,
                                        MAIN OFFICE

                                          by
                                            ----------------------------------
                                          Name:
                                          Title:

                                        CREDIT SUISSE,

                                          by
                                            ----------------------------------
                                          Name:
                                          Title:

                                          by
                                            ----------------------------------
                                          Name:
                                          Title:

                                        THE FIRST NATIONAL BANK OF CHICAGO,

                                          by
                                            ----------------------------------
                                          Name:
                                          Title:



<PAGE>



                                                                              12


                                      FLEET BANK,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                      THE FUJI BANK, LIMITED,
                                      NEW YORK BRANCH,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                      THE INDUSTRIAL BANK OF OF JAPAN TRUST
                                      COMPANY,

                                        by JOHN V. VELTON
                                          --------------------------------------
                                          Name:  John V. Velton
                                          Title: Senior Vice President

                                      LLOYDS BANK PLC,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                      MELLON BANK, N.A.,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:




<PAGE>



                                                                              13


                                      MIDLAND BANK PLC, NEW YORK BRANCH,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                      MORGAN GUARANTY TRUST COMPANY OF
                                      NEW YORK,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                      NATIONAL WESTMINSTER BANK PLC,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                      NATIONAL WESTMINSTER BANK PLC,
                                      NASSAU BRANCH,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                      NATIONBANK, N.A.

                                        by  MARCUS BOYER
                                          --------------------------------------
                                          Name: MARCUS BOYER
                                          Title: SENIOR VICE PRESIDENT

                                      PNC BANK, N.A.,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:




<PAGE>


                                                                              14



                                     ROYAL BANK OF CANADA,

                                        by D. S. BRYSON
                                          --------------------------------------
                                          Name D. S. Bryson
                                          Title: Senior Manager

                                     THE SAKURA BANK, LIMITED

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                     THE SANWA BANK, LIMITED, NEW YORK
                                     BRANCH,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                     SOCIETE GENERALE,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                     THE SUMITOMO BANK, LIMITED,
                                     NEW YORK BRANCH,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title:

                                     TORONTO DOMINION (NEW YORK), INC.,

                                        by
                                          --------------------------------------
                                          Name:
                                          Title: