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                                                                   EXHIBIT 10(a)




March 15, 1999


Mr. J. Kelley Williams
Chief Executive Officer/Chairman of the Board
ChemFirst Inc.
700 North Street
Jackson, MS  39202          PRIVILEGED AND CONFIDENTIAL

RE: Termination Agreement


Dear Kelley:

          ChemFirst Inc. (the "Company") considers it essential to the best
interests of its stockholders to foster the continuous employment of key
management personnel. In this connection, the Board of Directors of the Company
(the "Board") recognizes that, as is the case with many publicly held
corporations and their subsidiaries, the possibility of a Change in Control may
exist and that such possibility, and the uncertainty and questions which it may
raise, may result in the departure or distraction of management personnel to the
detriment of the Company and its stockholders.

          The Board has determined that appropriate steps should be taken to
reinforce and encourage the continued attention and dedication of the Company's
management to their assigned duties, without distraction in the face of
potentially disturbing circumstances arising from the possibility of a Change in
Control of the Company, although no such change is now contemplated.

          In order to induce you to remain in the employ of the Company and in
consideration of your agreement set forth in Subsection 2(iii) hereto, the
Company agrees that you shall receive the severance benefits set forth in this
letter agreement ("Agreement") in the event your employment with the Company is
terminated subsequent to a "Change in Control" of the Company (as defined in
Section 2 hereof) under the circumstances described below. This letter, however,
does not otherwise change your employment arrangements and except for the
conditions contained therein pertaining to a Change in Control, your continued
employment continues to be subject to the will of the Board of the Company.


          1. Term of Agreement. This Agreement shall be deemed effective on June
1, 1996 and shall continue in effect through May 31, 1999 (the "Original Term");
provided, however, that commencing on June 1, 1999, the term of this Agreement
shall automatically be extended for one additional term of three (3) years
beyond May 31, 1999, unless not later than June 30 of that year, the



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Company shall have given notice that it does not wish to extend this Agreement.
Notwithstanding the above, if a Change in Control (as defined in Section 2
below) of the Company shall have occurred during the original or extended term
of this Agreement, this Agreement shall continue in effect for a period of three
(3) years beyond the month in which such Change in Control occurred; provided
that, if you qualify as a Bona Fide Executive ("Bona Fide Executive") as that
term is defined under the Fair Labor Standards Act (29 C.F.R. Section 1625.12),
as may be amended, in no event shall this Agreement extend beyond the end of the
month in which you reach the age of 70 years.


          2. Change in Control.

               (i) No benefits shall be payable hereunder unless there shall
          have been a Change in Control of the Company, as set forth below. For
          purposes of the Agreement, a "Change in Control" of the Company shall
          be deemed to have occurred if:

                    (A) any "person" (as defined in Section 3(a) (9) of the
               Securities Exchange Act of 1934, as amended (the "Exchange Act"),
               as modified and used in Sections 13 (d) and 14 (d) thereof),
               other than (i) the Company or any of its subsidiaries, (ii) a
               trustee or any fiduciary holding securities under an employee
               benefit plan of the Company or any of its subsidiaries, (iii) an
               underwriter temporarily holding securities pursuant to an
               offering of such securities, or (iv) a corporation owned,
               directly or indirectly, by the stockholders of the Company in
               substantially the same proportions as their ownership of stock of
               the Company (a "Person"), is or becomes the "beneficial owner"
               (as defined in Rule 13d-3 under the Exchange Act), directly or
               indirectly, of securities of the Company representing twenty
               percent (20%) or more of the combined voting power of the
               Company's then outstanding securities; or

                    (B) during any period of two consecutive years (not
               including any period prior to the execution of this Agreement),
               individuals who at the beginning of such period constitute the
               Board and any new director (other than a director designated by a
               Person who has entered into an agreement with the Company to
               effect a transaction described in clause (A), (C) or (D) of this
               Subsection) whose election by the Board or nomination for
               election by the Company's stockholders was approved by a vote of
               at least two-thirds (2/3) of the directors then still in office
               who either were directors at the beginning of the period or whose
               election or nomination for election was previously so approved,
               cease for any reason to constitute a majority thereof; or

                    (C) the shareholders of the Company approve a merger or
               consolidation of the Company with any other corporation, other
               than (i) a merger or consolidation which would result in the
               voting securities of the Company outstanding immediately prior
               thereto continuing to represent (either by remaining outstanding
               or be being converted into voting securities of the surviving
               entity or any parent thereof), in combination with the ownership
               of any trustee or other fiduciary holding securities under an
               employee benefits plan of the Company, at least 80% of the
               combined voting power of the voting securities of the Company or
               such surviving entity or any parent thereof


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               outstanding immediately after such merger or consolidation, or
               (ii) a merger or consolidation effected to implement a
               recapitalization of the Company (or similar translation) in which
               no Person is or becomes the beneficial owner (determined pursuant
               to Subsection A above) of twenty percent (20%) or more of the
               combined voting power of the Company's then outstanding
               securities; or

                    (D) the shareholders of the Company approve a plan of
               complete liquidation of the Company or an agreement for the sale
               or disposition by the Company of all or substantially all the
               Company's assets.

               (ii) For purposes of this Agreement, a "Potential Change in
          Control" of the Company shall be deemed to have occurred if:

                    (A) the Company enters into an agreement, the consummation
               of which would result in the occurrence of a Change in Control of
               the Company;

                    (B) any person (including the Company) publicly announces an
               intention take or to consider taking actions which if consummated
               would constitute a Change in Control of the Company;

                    (C) any person, other than a trustee or other fiduciary
               holding securities under an employee benefit plan of the Company
               or a corporation owned, directly or indirectly, by the
               stockholders of the Company in substantially the same proportions
               as their ownership of stock of the Company, who is or becomes the
               beneficial owner, directly or indirectly, of securities of the
               Company representing nine and a half (9.5%) percent or more of
               the combined voting power of the Company's then outstanding
               securities, increases his beneficial ownership of such securities
               by five (5%) or more over the amount theretofore owned by such
               person; or

                    (D) the Board adopts a resolution to the effect that, for
               purposes of this Agreement, a Potential Change in Control of the
               Company has occurred.

               (iii) You agree that, subject to the terms and conditions of this
          Agreement, in the event of a Potential Change in Control of the
          Company, you will remain in the employ of the Company until the
          earliest of (A) a date which is six (6) months from the occurrence of
          such Potential Change in Control of the Company, (B) the termination
          by you of your employment by reason of Disability, as defined in
          Subsection 3(i), or (C) the occurrence of a Change in Control of the
          Company.

               (iv) Notwithstanding the foregoing, neither a "Change in Control"
          nor a "Potential Change in Control" shall be deemed to have occurred
          by virtue of the Company entering into any agreement with respect to,
          the public announcement of, the approval by the Company's shareholders
          or directors of, or the consummation of, any transaction or series of
          integrated transactions (including any merger or other business
          combination transaction) entered into in connection with, or expressly
          conditioned upon the occurrence of, a Spin-Off Transaction (as 


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          defined below) immediately following which the recordholders of the
          common stock of the Company immediately prior to such transaction or
          series of transactions continue to have substantially the same
          proportionate ownership in an entity (the "Spun-Off Entity") which
          owns all or substantially all of the assets of either of the Company's
          Principal Businesses (as defined below) immediately following such
          transaction or series of transactions (such transaction or series of
          transactions, a "Spin-Off Transaction"); provided that such Spin-Off
          Transaction (including any related merger or other business
          combination transaction) has been approved by a vote of a majority of
          the Company's Continuing Directors (as defined below) then in office.
          For purposes of this Agreement (1) "Principal Businesses" shall mean
          either of the Company's Chemical or Fertilizer businesses as described
          in the Company's Annual Report on Form 10-K for the fiscal year ended
          June 30, 1995 and (2) "Continuing Director" shall mean any member of
          the Board of Directors of the Company who is a member of the Board of
          Directors as of the date of this Agreement and any person who
          subsequently becomes a member of the Board of Directors, if such
          person's nomination for election or election to the Board of Directors
          is recommended or approved by a majority of the Continuing Directors.

          3. Termination Following Change in Control. If any of the events
described in Subsection 2(i) hereof constituting a Change in Control of the
Company shall have occurred, you shall be entitled to the benefits provided in
Subsection 4(iii) and (iv) hereof upon the subsequent termination of your
employment during the term of this Agreement unless such termination is (A)
because of your death or Disability as defined in Section 3(i), or (B) by the
Company for Cause, or upon your resignation within thirty-six (36) months of the
occurrence of such events as specified in Section 2.

               (i) Disability. If, as a result of your incapacity due to
          physical or mental illness, you shall have been absent from the
          full-time performance of your duties with the Company for six (6)
          consecutive months, and within thirty (30) days after written notice
          of termination is given you shall not have returned to the full-time
          performance of your duties, your employment may be terminated for
          "Disability".

               (ii) Cause. Termination by the Company of your employment for
          "Cause" shall mean termination upon (A) the willful and continued
          failure by you to substantially perform your duties with the Company
          (other than any such failure resulting from your incapacity due to
          physical or mental illness) or any such actual or anticipated failure
          after the issuance of a Notice of Termination after a written demand
          for substantial performance is delivered to you by the Board, which
          demand specifically identifies the manner in which the Board believes
          that you have not substantially performed your duties, or (B) the
          willful engaging by you in conduct which is demonstrably and
          materially injurious to the Company, monetarily or otherwise. For
          purposes of this Subsection, an act, or failure to act, shall be
          deemed "willful" if done, or omitted to be done, by you other than in
          good faith and without reasonable belief that your action or omission
          was in the best interest of the Company. Notwithstanding the
          foregoing, you shall not be deemed to have been terminated for Cause
          unless and until there shall have been delivered to you a copy of a
          resolution duly adopted by the affirmative vote of a minimum of
          three-quarters (3/4) of the entire membership of the 


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          Board at a meeting of the Board called and held for such purpose
          (after reasonable notice to you and opportunity for you, together with
          your counsel, to be heard before the Board), finding that in good
          faith opinion of the Board you were guilty of conduct set forth above
          in clauses (A) or (B) of the first sentence of this Subsection and
          specifying the particulars thereof in detail.

                  (iii) Notice of Termination. Any purported termination of your
          employment by the Company or by you shall be communicated by written
          Notice of Termination to the other party hereto in accordance with
          Section 6 hereof. For purposes of this Agreement, a "Notice of
          Termination" shall mean a notice which shall indicate the specific
          termination provision in this Agreement relied upon and shall set
          forth in reasonable detail the facts and circumstances claimed to
          provide a basis for termination of your employment under the
          provision so indicated.
          
               (iv) Date of Termination, Etc. "Date of Termination" shall mean
          the following: (A) if your employment is terminated for Disability,
          thirty (30) days after Notice of Termination is given (provided that
          you shall not have returned to the full-time performance of your
          duties during such thirty (30) day period), and (B) if your employment
          is terminated pursuant to Subsection (ii) above or for any other
          reason (other than Disability), the date specified in the Notice of
          Termination (which, in the case of a termination pursuant to
          Subsection (ii) above shall not be less than thirty (30) days from the
          date such Notice of Termination is given); provided that if within
          fifteen (15 days after any Notice of Termination is given, or if
          later, prior to the Date of Termination (as determined without regard
          to this provision), the party receiving such Notice of Termination
          notifies the other party that a dispute exists concerning the
          termination, the Date of Termination shall be the date on which the
          dispute is finally determined, either by mutual written agreement of
          the parties, by a binding arbitration award, or by a final judgment,
          order or decree of a court of competent jurisdiction (which is not
          appealable or with respect to which the time for appeal therefrom has
          expired and no appeal has been perfected); provided further that the
          Date of Termination shall be extended by a notice of dispute only if
          such notice is given in good faith and the party giving such notice
          pursues the resolution of such dispute with reasonable diligence.
          Notwithstanding the pendency of any such dispute, the Company will
          continue to pay you your full compensation in effect when the notice
          giving rise to the dispute was given (including, but not limited to
          base salary) and continue your participation in all compensation,
          benefit and insurance plans in which you were participating when the
          notice giving rise to the dispute was given, until the dispute is
          finally resolved in accordance with this Subsection. Amounts paid
          under this Subsection are in addition to all other amounts due under
          this Agreement and shall not be offset against or reduce any other
          amounts due under this Agreement.

          4. Compensation Upon Termination or During Disability. Following a
          Change in Control of the Company, as defined by Subsection 2(i), upon
          termination of your employment or during a period of disability, you
          shall be entitled to the following benefits.


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               (i) During any period that you fail to perform your full-time
          duties with the Company as a result of incapacity due to physical or
          mental illness, you shall continue to receive your base salary at the
          rate in effect at the commencement of any such period, together with
          all compensation payable to you under the Company's annual bonus plan,
          the First Mississippi Corporation 1980 Long-Term Incentive Plan, the
          First Mississippi Corporation 1988 Long-Term Incentive Plan, the First
          Mississippi Corporation 1995 Long-Term Incentive Plan, or other plan
          during such period, until this Agreement is terminated pursuant to
          Section 3(i) hereof. Thereafter your benefits shall be determined
          under the Company's retirement, insurance and other compensation
          programs then in effect in accordance with the terms of such programs.

               (ii) If your employment shall be terminated by the Company for
          Cause or by you other than for Disability, or death, the Company shall
          pay you your full base salary through the Date of Termination at the
          rate in effect at the time Notice of Termination is given, plus all
          other amounts to which you are entitled under any compensation plan of
          the Company at the time such payments are due, and the Company shall
          have no further obligations to you under this Agreement.

               (iii) If your employment by the Company shall be terminated (a)
          by the Company other than for Cause or Disability, then you shall be
          entitled to the benefits provided below:

                    (A) The Company shall pay you your full base salary through
                    the Date of Termination at the rate in effect at the time
                    Notice of Termination is given, plus all other amounts to
                    which you are entitled under any compensation plan of the
                    Company, at the time such payments are due, except as
                    otherwise provided below.

                    (B) (1) In lieu of any further salary payments to you for
                    periods subsequent to the Date of Termination, the Company
                    shall pay to you, subject to subsection 2 below, a lump sum
                    severance payment (together with the payments provided in
                    Paragraphs C, E and F below and any payment you may receive
                    pursuant to Paragraph D below, the "Severance Payments")
                    equal to 3 times the sum of (i) your average annual base
                    salary for the five (5) full years preceding the year in
                    which the Date of Termination occurs averaged over said five
                    (5) full years, and (ii) either the average annual bonus
                    earned by you with respect to such five (5) year period, or
                    the average annual bonus earned by you with respect to such
                    five (5) year period immediately preceding the date of the
                    Change in Control, whichever is higher (taking the value of
                    such bonuses into account whether paid in cash or defined or
                    converted into another form of compensation under any
                    Company plan).

                         (2) Notwithstanding subsection (B)(1) above, if you
                    will reach the age of 70 years within 36 months after the
                    Date of Termination, then the lump sum severance payment
                    calculated in subsection (B)(1) above shall be reduced by
                    multiplying such payment by a fraction, the numerator of
                    which shall equal 


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                    one plus the number of full calendar months between the Date
                    of Termination and the date on which you attain the age of
                    70, if you qualify as a Bona Fide Executive, and the
                    denominator of which shall equal 36.

                    (C) The Company shall continue to provide you with medical
               insurance, life insurance and disability insurance in the amounts
               and upon the terms and conditions present immediately prior to
               Notice of Termination for a period of three years following the
               Date of Termination. However, if during such three year period
               you (i) become re-employed with another employer and you are
               eligible to receive medical or other welfare benefits under
               another employer provided plan, or (ii) you reach the age of 70
               years and do not qualify as a Bona Fide Executive, then the
               medical and other welfare benefits described above shall no
               longer be provided by the Company. In the event that the Company
               cannot, despite its best efforts, provide such coverage under its
               benefit plans, it shall arrange for equivalent coverage outside
               such plans.

                    (D) Notwithstanding any provision of the Company's Long-Term
               Incentive Plans as amended from time to time, or any other
               compensation arrangements then in effect, the Company shall pay
               to you a lump sum amount equal to the sum of any incentive
               compensation which has been allocated or awarded to you for a
               year or other measuring period preceding the Date of Termination,
               but has not yet been paid.

                    (E) Except for Incentive Stock Options ("ISOs") which are
               hereby specifically excluded, in lieu of shares of common stock
               of the Company ("Company Shares") issuable upon exercise of
               outstanding options ("Options"), granted to you under the
               Company's Long-Term Incentive Plans as amended from time to time,
               or any other plan then in effect (which Options shall be canceled
               upon the making of the payment referred to below), unless you
               notify the Company by giving notice in accordance with Section 6
               hereof within fifteen (15) days after receipt of Notice of
               Termination that you do not wish such payment, the Company shall
               pay to you not later then the fifth day following the Date of
               Termination, an amount in cash equal to the product of (i) the
               difference (to the extent that such difference is a positive
               number) obtained by subtracting the per share exercise price of
               each Option held by you whether or not then fully exercisable
               from the higher of (A) the closing price of Company Shares as
               reported on the New York Stock Exchange on the Date of
               Termination, or (B) the highest per share price of Company Shares
               actually paid in connection with any Change in Control of the
               Company, and (ii) the number of Company Shares covered by each
               such Option. In lieu of convertible debentures of the Company
               ("the Debentures") issuable upon exercise of outstanding options
               ("Debenture Options") granted to you under the Company's
               Long-Term Incentive Plans, as amended from time to time, or any
               other plan then in effect (which Debenture Options shall be
               canceled upon the making of the payment referred to below),
               unless you notify the Company by giving notice in accordance with
               Section 6 hereof within fifteen (15) days after receipt of Notice
               of Termination that you do not wish to receive such payment, the
               Company will pay to you, not later than the fifth 


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               (5th) day following the Date of Termination, an amount in cash
               equal to the product of (i) the difference (to the extent that
               such difference is a positive number) obtained by subtracting the
               per share price at which the Debentures would be convertible into
               Company Shares whether or not then fully exercisable from the
               higher of (A) the closing price of Company Shares as reported on
               the New York Stock Exchange on the Date of Termination, or (B)
               the highest per share price for Company Shares actually paid in
               connection with any Change in Control of the Company, and (ii)
               the number of Company Shares issuable upon conversion of the
               Debentures covered by the Debenture Options. In lieu of any
               conversion rights under any outstanding Debentures issued upon
               the exercise of Debenture Options (which Debentures shall be
               canceled upon the making of the payment referred to below),
               unless you notify the Company by giving notice in accordance with
               Section 6 hereof within fifteen (15) days after receipt of Notice
               of Termination that you do not wish such payment, the Company
               will pay to you an amount in cash equal to the product of (i) the
               higher of (A) the closing price of Company Shares as reported on
               the New York Stock Exchange on the Date of Termination or (B) the
               highest per share price for Company Shares actually paid in
               connection with any Change in Control of the Company, and (ii)
               the number of Company Shares into which such Debentures are then
               convertible. In lieu of any rights under any outstanding
               Performance Shares or Performance Units (as each term is defined
               in the First Mississippi Corporation 1995 Long-Term Incentive
               Plan) granted to you by the Company, the Company shall, pursuant
               to the terms and conditions of the First Mississippi Corporation
               1995 Long-Term Incentive Plan, pay to you in cash an amount equal
               to the value of such Performance Shares or Performance Units.

                    (F) If on the Date of Termination, you are not 100% vested
               under the Retirement Plan For Employees of First Mississippi
               Corporation and the corresponding provisions of the First
               Mississippi Corporation Benefits Restoration Plan (together the
               "Retirement Plan"), the Company shall pay you a lump sum equal to
               the present value of a straight life annuity benefit commencing
               at the earliest date you could have elected to receive benefits
               under the Retirement Plan (using the interest rate and the
               mortality table then in use under the Retirement Plan) to provide
               the excess of:

                         (i) an aggregate benefit equal to the benefit that
                    would have been paid under the Retirement Plan if you were
                    100% vested under such Retirement Plan, over

                         (ii) the aggregate benefit actually payable under the
                    Retirement Plan.

               In addition, if on the Date of Termination you are not 100%
               vested under either the First Mississippi Corporation 401(k)
               Savings Plan and the corresponding provisions of the First
               Mississippi Corporation Benefits Restoration Plan (effective
               March 1, 1989),


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               the Company shall pay you a lump sum equal to the current amount
               forfeited under each such plan.

                    (G) The Company shall also pay to you all legal fees and
               expenses incurred by you as a result of such termination
               (including all such fees and expenses, if any, incurred in
               contesting or disputing any such termination or in seeking to
               obtain or enforce any right or benefit provided by this Agreement
               or in connection with any tax audit or proceeding to the extent
               attributable to the application of Section 4999 of the Internal
               Revenue Code of 1986, as amended (the "Code") to any payment or
               benefit provided hereunder).

                    (H) The payments provided for in paragraphs (A), (B), (D),
               (E) and (F) above and in Paragraph (iv) below, shall be made not
               later than the fifth (5th) day following the Date of Termination,
               provided, however, that if the amounts of such payments cannot be
               finally determined on or before such day, the Company shall pay
               to you on such day an estimate, as determined in good faith by
               the Company, of the minimum amount of such payments and shall pay
               the remainder of such payments (together with interest at the
               rate provided in Section 1274(b)(2)(B) of the Code) as soon as
               the amount thereof can be determined, but in no event later than
               the thirtieth (30th) day after the Date of Termination. In the
               event that the amount of the estimated payments exceeds the
               amount subsequently determined to have been due, such excess
               shall constitute a loan by the Company to you payable on the
               fifth (5th) day after demand by the Company (together with
               interest at the rate provided in Section 1274(b)(2)(B) of the
               Code).

               (iv) In the event that you become entitled to the Severance
          Payments or to any other payments or benefits received or to be
          received by you in connection with a Change in Control of the Company
          or your termination of employment (whether pursuant to the terms of
          this Agreement or any other plan, arrangement or agreement with the
          Company, (collectively with the Severance Payments, the "Total
          Payments"), and if any of the Total Payments will be subject to the
          tax (the "Excise Tax") imposed by Section 4999 of the Code, the
          Company shall pay to you at the time specified in paragraph (H),
          above, an additional amount (the "Gross-Up Payment") such that the net
          amount retained by you, after deduction of any Excise Tax on the Total
          Payments and any income tax, employment tax and Excise Tax upon the
          payment provided for by this paragraph, shall be equal to the Total
          Payments. For purposes of determining whether any of the Total
          Payments will be subject to the Excise Tax and the amount of such
          Excise Tax, (i) the Total Payments shall be treated as "parachute
          payments" within the meaning of Section 280G(b)(2) of the Code, and
          all "excess parachute payments" within the meaning of Section
          280G(b)(2) shall be treated as subject to the Excise Tax, unless in
          the opinion of tax counsel selected by the Company's independent
          auditors and acceptable to you such other payments or benefits (in
          whole or in part) do not constitute parachute payments, or such excess
          parachute payments (in whole or in part) represent reasonable
          compensation for services actually rendered within the meaning of
          Section 280G(b)(4) of the Code in excess of the base amount within the
          meaning of Section 280G(b)(3) of the Code, or are otherwise not
          subject to the Excise Tax, (ii) the amount of the Total Payments which
          shall

<PAGE>   10

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          be treated as subject to the Excise Tax shall be equal to the lesser
          of (A) the total amount of the Total Payments or (B) the amount of
          excess parachute payments within the meaning of Section 280(b)(1)
          (after applying clause (i), above), and (iii) the value of any
          non-cash benefits or any deferred payment or benefit shall be
          determined by the Company's independent auditors in accordance with
          the principles of Sections 280(G)(d)(3) and (4) of the Code. For
          purposes of determining the amount of the Gross-Up Payment, you shall
          be deemed to pay income taxes at the highest marginal rate of income
          taxation in the calendar year in which the Gross-Up Payment is to be
          made. In the event that the Excise Tax is subsequently determined to
          be less than the amount taken into account hereunder at the time of
          termination of your employment, you shall repay to the Company at the
          time that the amount of such reduction in Excise Tax is finally
          determined the portion of the Gross-Up Payment attributable to such
          reduction (plus the portion of the Gross-Up Payment attributable to
          the Excise Tax and income tax imposed on the Gross-Up Payment being
          repaid by you if such repayment results in a reduction in Excise Tax
          and/or an income tax deduction) plus interest on the amount of such
          repayment at the rate provided in Section 127(b)(2)(B) of the Code. In
          the event that the Excise Tax is determined to exceed the amount taken
          into account hereunder at the time of the termination of your
          employment (including by reason of any payment the existence or amount
          of which cannot be determined at the time of the Gross-Up Payment),
          the Company shall make an additional Gross-Up Payment in respect of
          such excess (plus any interest payable with respect to such excess) at
          the time that the amount of such excess is finally determined.

               (v) Notwithstanding anything to the contrary in this Agreement,
          amounts received under paragraph (iii) above shall be in lieu of any
          other amount of severance relating to salary or bonus continuation to
          be received by you upon termination of employment under any severance
          plan, policy or arrangement of the Company.

               (vi) You shall not be required to mitigate the amount of any
          payment provided for in this Paragraph 4 by seeking other employment
          or otherwise, nor shall the amount of any payment or benefit provided
          for in this Paragraph 4 be reduced by any compensation or benefits
          earned by you as the result of employment by another employer (except
          as provided in paragraph (iii)(C) above), by retirement benefits, by
          offset against any amount claimed to be owed by you to the Company, or
          otherwise.

               (vii) In addition to all other amounts payable to you under this
          Paragraph 4, you shall be entitled to receive all benefits payable to
          you under the 401(k) Savings Plan, and any other plan or agreement
          relating to retirement benefits.

          5. Successors; Binding Agreement.

               (i) The Company will require any successor (whether direct or
          indirect, by purchase, merger, consolidation or otherwise) to all or
          substantially all of the business and /or assets of the Company to
          expressly assume and agree to perform this Agreement in the same
          manner and to the same extent that the Company would be required to
          perform it if no such succession had taken place. Failure of the
          Company to obtain such assumption and agreement

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          prior to the effectiveness of any such succession shall be a breach of
          this Agreement and shall entitle you to compensation from the Company
          in the same amount and on the same terms as you would be entitled to
          hereunder if you terminated your employment for any reason following a
          Change in Control of the Company, except that for purposes of
          implementing the foregoing, the date on which any such succession
          becomes effective shall be deemed the Date of Termination. As used in
          this Agreement, "Company" shall mean the Company as hereinbefore
          defined and any successor to its business and/or assets as aforesaid
          which assumes and agrees to perform this Agreement by operation of
          law, or otherwise.

               (ii) This Agreement shall inure to the benefit of and be
          enforceable by your personal or legal representatives, executors,
          administrators, successors, heirs, distributees, devisees and
          legatees. If you should die while any amount would still be payable to
          you hereunder if you had continued to live, all such amounts, unless
          otherwise provided herein, shall be paid in accordance with the terms
          of this Agreement to your devisee, legatee or other designee or, if
          there is no such designee, to your estate. Notwithstanding the
          foregoing, you and the Company hereby agree that, upon the
          distribution (the "Distribution") of shares of common stock of the
          Spun-Off Entity to stockholders of the Company in a Spin-Off
          Transaction, the Spun-Off Entity shall assume all of the obligations
          and succeed to all of the rights of the Company under this Agreement,
          the Company shall be released of all of its obligations under this
          Agreement and thereafter, as used in this Agreement, the term
          "Company" shall mean the Spun-Off Entity and any successor to its
          business and/or assets which assumes and agrees to perform this
          Agreement by operation of law or otherwise. This Agreement shall
          terminate and be of no further force and effect and you hereby agree
          to release the Company and the Spun-Off Entity from any obligations
          hereunder upon the Distribution if, as of the Distribution, you are
          not employed by the Spun-Off Entity or one of its direct or indirect
          subsidiaries.

          6. Notices. For the purpose of this Agreement, notices and all other
communications provided for in the Agreement shall be in writing and shall be
deemed to have been duly given when delivered or mailed by United States
registered mail, return receipt requested, postage prepaid, addressed to the
respective addresses set forth on the first page of this Agreement, provided
that all notices to the Company shall be directed to the attention of the Board
with a copy to the Secretary of the Company, or to such other address as either
party may have furnished to the other in writing in accordance herewith, except
that notice of change of address shall be effective only upon receipt.

          7. Miscellaneous. No provision of this Agreement may be modified,
waived or discharged unless such waiver, modification or discharge is agreed to
in writing and signed by you and such officer as may be specifically designated
by the Board. No waiver by either party hereto at any time of any breach by the
other party hereto of, or compliance with, any condition or provision of this
Agreement to be performed by such other party shall be deemed a waiver of
similar or dissimilar provisions or conditions at the same or at any prior or
subsequent time. No agreements or representations, oral or otherwise, express or
implied, with respect to the subject matter hereof have been made by either
party which are not expressly set forth in this Agreement. The validity,
interpretation, construction and performance of this Agreement shall be governed
by the laws of the State of Mississippi. All references to Sections of the
Exchange Act or the Code shall be deemed also

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to refer to any successor provisions to such Sections. Any payments provided for
hereunder shall be paid net of any applicable withholding required under
federal, state or local law. The obligations of the Company under Paragraph 4
shall survive the expiration of the term of this Agreement.

          8 Validity. The invalidity or unenforceability of any provision of
this Agreement shall not affect the validity or enforceability of any other
provision of this Agreement, which shall remain in full force and effect.

          9. Counterparts. This Agreement may be executed in several
counterparts, each of which shall be deemed to be an original, but all of which
together will constitute one and the same instrument.

          10. Amendment. This Agreement amends and restates in its entirety that
certain Termination Agreement dated May 29, 1996 between J. Kelley Williams and
First Mississippi Corporation, which was assigned to and assumed by ChemFirst
Inc.

If this letter sets forth our agreement on the subject matter hereof, please
sign and return the enclosed copy of this letter to Teresa Holland in the CEM
human resources department which will then constitute our agreement on this
subject.



Sincerely yours,

CHEMFIRST INC.


/s/ Richard P. Anderson        
-------------------------
Richard P. Anderson
Chairman, Compensation and Human Resources Committee



ACCEPTED AND AGREED TO on this, the 22nd day of March, 1999.


/s/ J. Kelley Williams            
-------------------------
J. Kelley Williams