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                                                                Exhibit 3.i(w)

                      RESTATED CERTIFICATE OF INCORPORATION

                                      OF

                            AMERICAN SALT COMPANY


                      Under Section 245 of the General
                 Corporation Law of the State of Delaware


     AMERICAN SALT COMPANY, a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware (the
"Corporation"), DOES HEREBY CERTIFY:

     FIRST:  That the original Certificate of Incorporation of the
Corporation was filed with the Secretary of State, Dover, Delaware, on the
21st day of January, 1988, a Restated Certificate of Incorporation was filed
on the 19th day of February 1988 and an Amendment to the Restated Certificate
of Incorporation was filed on the 24th day of February 1988.

     SECOND:  That the Restated Certificate of Incorporation of the
Corporation has been duly adopted in accordance with the provisions of
Section 141(f), 228(a), 242 and 245 of the General Corporation Law of the
State of Delaware.

     THIRD:  That the text of the Certificate of Incorporation of the
Corporation is hereby restated by this Certificate, to read in full, as
follows:

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                                                                      EXHIBIT A

                                   RESTATED

                          CERTIFICATE OF INCORPORATION

                                     -of-

                              AMERICAN SALT COMPANY

                                    -oo0oo-

     FIRST:  The name of the Corporation is American Salt Company
(hereinafter sometimes called the "Corporation").

     SECOND:  The address of the Corporation's registered office in the State
of Delaware is Corporation Trust Center, 1209 Orange Street, City of
Wilmington, County of New Castle, State of Delaware 19801. The name of its
registered agent at such address is The Corporation Trust Company.

     THIRD:  The nature of the business or purposes to be conducted or
promoted are to engage in any lawful act or activity for which corporations
may be organized under the General Corporation Law of the State of Delaware.

     FOURTH:  The total number of shares of stock which the Corporation has
authority to issue is 3,000 shares of Common Stock and the par value of each
such share is $.01.

     FIFTH:  The following additional provisions are inserted for the
management of the business and for the conduct of the affairs of the
Corporation, and for the creation, definition, limitation and regulation of
the powers of the Corporation, the directors and the stockholders:

     1.  Election of directors need not be by written ballot. The Board of
Directors shall have power to make, alter, amend and repeal the By-Laws of
the Corporation and to fix the compensation of directors for services in any
capacity.

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                                      -2-

     2.  Any corporate action, with respect to which the vote of the
stockholders at a meeting thereof is required or permitted by any provision
of the General Corporation Law of the State of Delaware or of the Certificate
of Incorporation or the By-Laws of the Corporation, is authorized to be taken
and may be taken without that vote and meeting, and that vote and meeting may
be dispensed with, with the written consent of the holders of a majority (or,
if with respect to a particular corporate action where the General
Corporation Law of the State of Delaware or the Certificate of Incorporation
or the By-Laws of the Corporation specifies a greater percentage, by the
holders of that greater percentage) of the stock that would have been
entitled to vote upon that action if a meeting was held. Prompt notice shall
be given to all stockholders of the taking of any corporate action pursuant
to the provisions of this paragraph 2 unless that action has been consented
to in writing by the holders of all of the stock that would have been
entitled to vote upon that action if a meeting were held.

     3.  A director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or
a knowing violation of law, (iii) under Section 174 of the Delaware General
Corporation Law, or (iv) for any transaction from which the director derived
an improper personal benefit.

     SIXTH:  The Corporation shall indemnify any person who was or is a
party, or is threatened to be made a party, to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative
or investigative, including an action by or in the right of the Corporation,
by reason of the fact that he, or the person whose legal representative he
is, (1) is or was a stockholder, director, officer, employee or agent of the
Corporation (including the incorporator thereof), or (2) is or was serving at
the request of the Corporation as a director, officer, employee or agent of
another corporation, partnership, joint venture, rust or other enterprise, or
(3) is or was a director, officer or employee of the Corporation serving at
the request of the Corporation as a fiduciary of an employee benefit plan or
trust maintained for the benefit of employees of the Corporation or employees
of any such other enterprise,

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                                       -3-


partnership, joint venture, trust, or other enterprise, against judgments,
fines, penalties, amounts paid in settlement, and expenses, including
attorneys' fees, actually and reasonably incurred by him and the person whose
legal representative he is, in connection with such action, suit or
proceeding, or any appeal therein, to the fullest extent permitted by law.

         Expenses which may be indemnifiable under this Section incurred in
defending an action, suit or proceedings may be paid by the Corporation in
advance of the final disposition of such action, suit or proceeding as
authorized by the Board of Directors upon agreement by or on behalf of the
stockholder, director, officer, employee or agent, or his legal
representative, to repay such amount if he is later found not entitled to be
indemnified by the Corporation as authorized in this section.

         The Corporation shall not indemnify any stockholder, director,
officer, employee or agent against judgments, fines, amounts paid in
settlement and expenses, including attorneys' fees, to an extent greater than
that authorized by this Article Sixth, but the Corporation may procure
insurance providing greater indemnification and may share the premium cost
with any stockholder, director, officer, employee or agent on such basis as
may be agreed upon.

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STATE OF NEW YORK   )
                    : ss.:
COUNTY OF NEW YORK  )

        BE IT REMEMBERED that on this 29th day of March, 1990, personally
came before me Barbara J. Ellis, a Notary Public in and for the County and
State aforesaid, Anthony J. Petrocelli and Richard J. Donahue, known to me
personally to be such, and acknowledged that it is their respective act and
deed and that the facts stated therein are true.

        GIVEN under my hand and seal of office the day and year aforesaid.

                                /s/ Barbara J. Ellis
                             -----------------------------
                                   Notary Public

                                     BARBARA J. ELLIS
                           Notary Public, State of New York
                                    No. 31-4949879
                             Qualified in New York County
                           Commission Expires April 17, 1991

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                            CERTIFICATE OF AMENDMENT

                                       TO

                     RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                            AMERICAN SALT COMPANY

        AMERICAN SALT COMPANY, a corporation organized and existing under and
by virtue of the General Corporation Law of the State of Delaware (the
"Corporation"), DOES HEREBY CERTIFY:

                FIRST:  That the Board of Directors of the Corporation
        duly adopted a resolution setting forth a proposed amendment
        to the Restated Certificate of Incorporation of the
        Corporation, declaring said amendment to be advisable and
        calling a meeting of the stockholders of the Corporation for
        consideration thereof. The resolution setting forth the
        proposed amendment is as follows:

                RESOLVED, that Article First of the Restated Certificate
        of Incorporation of the Corporation be amended, and as amended
        said Article shall be and read in its entirety as follows:

                "FIRST:  The name of the Corporation is North American
        Salt Company (hereinafter sometimes called the "Corporation")."

                SECOND:  That in lieu of a meeting and a vote of stockholders,
        the holder of all of the outstanding stock of the Corporation has
        given its unanimous written consent to said amendment in accordance
        with the provisions of Section 228(a) of the General Corporation Law
        of the State of Delaware.

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                                       -2-

                THIRD:  That said amendment was duly adopted in accordance
        with the provisions of Section 242 of the General Corporation Law
        of the State of Delaware.

        IN WITNESS WHEREOF, the Corporation has caused this certificate of
amendment to be signed by Anthony J. Petrocelli, its Vice Chairman, Treasurer
and Assistant Secretary, and attested by Richard J. Donahue, its Senior Vice
President, Secretary and Assistant Treasurer, as of the 20th day of August,
1990.

                                    AMERICAN SALT COMPANY

                                    By: /s/ Anthony J. Petrocelli
                                        -----------------------------
                                        Anthony J. Petrocelli
                                        Vice Chairman, Treasurer
                                        and Assistant Secretary

ATTEST:  /s/ Richard J. Donahue
         -----------------------
         Richard J. Donahue
         Senior Vice President,
          Secretary and Assistant
          Treasurer


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                       CERTIFICATE OF AMENDMENT
                                  TO
                   RESTATED CERTIFICATE OF INCORPORATION
                                  OF
                      NORTH AMERICAN SALT COMPANY

        The undersigned officers, Robert E. Fowler, Jr. and Rose Marie
Williams, President and CEO, and Secretary, respectively of North American
Salt Company, a corporation organized and existing under the General
Corporation Law of the State of Delaware (the "Corporation"), do hereby
certify that:

1.  Paragraph FIRST of the Restated Certificate of Incorporation of the
    Corporation is hereby amended in its entirety as follows:

                        "FIRST:  The name of the corporation is IMC Salt Inc."

2.  This Certificate of Amendment was duly adopted by the sole director and
    sole voting stockholder of the Corporation according to the provisions
    of Sections 141(f), 229 and 242 of the General Corporation Law of the
    State of Delaware.

        IN WITNESS WHEREOF, the undersigned have hereunto subscribed their
names this 1st day of May, 1998.

                                NORTH AMERICAN SALT COMPANY
[SEAL]
                                By: /s/ Robert E. Fowler, Jr.
                                    -----------------------------
                                    Robert E. Fowler, Jr.

Attest:

/s/ Rose Marie Williams
- ---------------------------
Rose Marie Williams
Secretary