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                                                                  Exhibit 4.6(c)

                           AMENDMENT TO THE FIVE YEAR
                                CREDIT AGREEMENT
                          DATED AS OF JANUARY 27, 1999


         This Amendment to the $125,000,000 Five Year Credit Agreement dated as
of January 27, 1999 ("Amendment") is entered into as of January 22, 2003.

                                    RECITALS
                                    --------

               This Amendment is entered into in reference to the following
facts:

               (a) The Five Year Credit Agreement is dated as of January 27,
1999 (as the same may be amended, supplemented or otherwise modified from time
to time, the "Five Year Credit Agreement") among, inter alios, Arch Chemicals,
Inc., Olin Corporation, the Lenders and Agents party thereto and JPMorgan Chase
Bank, as Administrative Agent for the Lenders. Capitalized terms used in this
Amendment without definition shall have the respective meanings assigned to them
in the Five Year Credit Agreement.

               (b) The Borrower, the Agents and Required Lenders desire to amend
the Five Year Credit Agreement in order to make certain amendments to the
representations and warranties as more particularly described herein.

               NOW THEREFORE, in consideration of the mutual covenants contained
herein, the parties hereto hereby agree as follows:

                            ARTICLE ONE - AMENDMENT

               1.1 Amendment of Section 3.10. Section 3.10 shall be amended by
the deletion in its entirety of existing Section 3.10 and its substitution with
the following:

         "Section 3.10. ERISA. No ERISA Event has occurred or is reasonably
         expected to occur that, when taken together with all other such ERISA
         Events for which liability is reasonably expected to occur, could
         reasonably be expected to result in a Material Adverse Effect. The
         present value of all accumulated benefit obligations under each Plan
         (based on the assumptions used for purposes of Statement of Financial
         Accounting Standards No. 87) did not, as of the date of the most recent
         financial statements reflecting such amounts, exceed the fair market
         value of the assets of such Plan by an amount that could reasonably be
         expected to result in a Material Adverse Effect, and the present value
         of all accumulated benefit obligations of all underfunded Plans (based
         on the assumptions used for purposes of Statement of Financial
         Accounting Standards No. 87) did not, as of the date of the most recent
         financial statements reflecting such amounts, exceed the fair market
         value of the


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         assets of all such underfunded Plans by an amount that could reasonably
         be expected to result in a Material Adverse Effect."

                  ARTICLE TWO - REPRESENTATIONS AND WARRANTIES

               2.1 Borrower Representations and Warranties. In order to induce
the Agents and the Lenders to enter into this Amendment, the Borrower represents
and warrants as follows:

                    (a) The Borrower has the power and authority and has taken
all action necessary to execute, deliver and perform this Amendment and all
other agreements and instruments executed or delivered or to be executed or
delivered in connection herewith and therewith and this Amendment and such other
agreements and instruments constitute the valid, binding and enforceable
obligations of the Borrower.

                    (b) The Borrower's representations and warranties contained
in the Five Year Credit Agreement are true and correct in all respects on and as
of the date hereof as though made on and as of the date hereof and no Default or
Event of Default has occurred and is continuing as of the date hereof (for the
avoidance of doubt in each case for the purposes of this Section 2.1(b), after
giving effect to this Amendment and the amendment dated of even date herewith to
the 364-Day Facility).

               2.2 Acknowledgment of Borrower. The Borrower expressly
acknowledges and agrees that as of the date hereof, it has no offsets, claims or
defenses whatsoever against any of the Indebtedness or obligations owing under
the Five Year Credit Agreement.

                      ARTICLE THREE - CONDITIONS PRECEDENT

               3.1 Conditions to Effectiveness of this Amendment. The
effectiveness of this Amendment is subject to the satisfaction of the following
conditions on or before the date hereof:

                    (a) Receipt by the Administrative Agent of copies of this
Amendment duly executed by each of the Borrower and the Required Lenders.

                    (b) The Borrower shall have paid all fees, costs and
expenses owing to the Administrative Agent and the Administrative Agent's
counsel through the date hereof, including without limitation, in respect of the
preparation, execution and delivery of this Agreement.

                    (c) The Borrower shall have paid to each Lender executing
this Amendment an amendment fee equal to 0.050% of the total amount of the
Commitment of such Lender under the Five Year Credit Agreement.

                       ARTICLE FOUR - GENERAL PROVISIONS

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               4.1 Full Force and Effect. Except as expressly amended hereby,
the Five Year Credit Agreement and all other documents, agreements and
instruments relating thereto are and shall remain unmodified and in full force
and effect. Upon the effectiveness of this Amendment, on and after the date
hereof, each reference in the Five Year Credit Agreement to "THIS AGREEMENT,"
"HEREUNDER," "HEREOF," "HEREIN," or words of like import shall mean and be a
reference to the Five Year Credit Agreement as amended hereby, and this
Amendment and the Five Year Credit Agreement shall be read together and
construed as a single instrument.

               4.2 Counterparts. This Amendment may be executed in any number of
counterparts, each of which when so executed and delivered shall be deemed to be
an original and that all of which taken together shall constitute one and the
same instrument, respectively. Delivery of an executed counterpart of this
Amendment by facsimile shall be equally effective as delivery of a manually
executed counterpart of this Amendment. Any party delivering an executed
counterpart by facsimile shall also deliver a manually executed counterpart of
this Amendment, but failure to do so shall not effect the validity,
enforceability, of binding effect of this Amendment.

               4.3 Final Agreement. This Amendment is intended by the Borrower,
the Agents and the Lenders to be the final, complete, and exclusive expression
of the agreement between them with respect to the subject matter hereof. This
Amendment supersedes any and all prior oral or written agreements relating to
the subject matter hereof. This Amendment shall be binding upon the parties
hereto and their respective successors and assigns and shall inure to the
benefit of the parties hereto and the successors and assigns of the Lenders and
the Agents. The execution, delivery and effectiveness of this Amendment shall
not, except as expressly provided herein, operate as a waiver of any right,
power or remedy of the Lenders or the Agents under the Five Year Credit
Agreement, nor constitute a waiver of any provision of the Five Year Credit
Agreement.

               4.4 Governing Law. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS
OF THE PARTIES HEREUNDER SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND
ENFORCED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.




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               IN WITNESS WHEREOF, the parties hereto have caused this Amendment
to be duly executed as of the day and year first above written.

                               JPMORGAN CHASE BANK


                                        By: /s/ Lawrence Palumbo Jr.
                                        Name: Lawrence Palumbo Jr.
                                        Title: Vice President


                                        WACHOVIA BANK, N.A.


                                        By: /s/ Robert A. Brown
                                            -------------------------
                                        Name: Robert A. Brown
                                        Title: Director


                                        BANK OF AMERICA, N.A.,


                                        By: /s/ Donald J. Chin
                                            -------------------
                                        Name: Donald J. Chin
                                        Title: Managing Director


                                        THE BANK OF NEW YORK


                                        By: /s/ Joanna S. Bellocq
                                            ----------------------
                                        Name: Joanne S. Bellocq
                                        Title: Vice President


                                        FLEET NATIONAL BANK


                                        By: /s/ Marwan Isbaih
                                            ------------------------
                                        Name: Marwan Isbaih
                                        Title: Director


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                                        PNC BANK, NATIONAL ASSOCIATION


                                        By: /s/ Donald V. Davis
                                            --------------------
                                        Name: Donald V. Davis
                                        Title: Vice President


                                        ING (US) CAPITAL LLC


                                        By:
                                           ---------------------
                                        Name:
                                        Title:


                                        SUNTRUST BANK


                                        By: /s/ Frank A. Coe
                                        Name: Frank A. Coe
                                        Title: Vice President


                                        ABN AMRO BANK N.V.


                                        By:
                                           ---------------------
                                        Name:
                                        Title:


                                        STATE STREET BANK & TRUST COMPANY


                                        By:
                                           ---------------------
                                        Name:
                                        Title:



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Agreed and accepted:

ARCH CHEMICALS, INC.


By: /s/ W. Paul Bush
    -----------------
Name: W. Paul Bush
Title: Vice President  & Treasurer



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