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                                                                   Exhibit 10.11

                              ARCH CHEMICALS, INC.
                   1999 STOCK PLAN FOR NON-EMPLOYEE DIRECTORS
               (As Amended and Restated through January 30, 2003)

         1.       PURPOSE. The purpose of the Arch Chemicals, Inc. 1999 Stock
Plan for Non-employee Directors is to promote the long-term growth and financial
success of Arch Chemicals, Inc. by attracting and retaining non-employee
directors of outstanding ability and by promoting a greater identity of interest
between its non-employee directors and its shareholders.

         2.       DEFINITIONS. The following capitalized terms utilized herein
have the following meanings:

                   "Administrator" means the Vice President, Human Resources of
         the Company or his or her delegate.

                  "Annual Director Grant" means the number of phantom shares of
         Common Stock, Options and/or Performance Shares to be granted annually
         to a Non-employee Director pursuant to Section 6(a), such number shall
         be fixed by the Board during 1999 following the Distribution Date and
         may be adjusted prospectively by such Board from time to time
         thereafter.

                  "Arch Stock Account" means the Stock Account to which phantom
         shares of Common Stock are credited from time to time.

                  "Board" means the Board of Directors of the Company.

                  "Cash Account" means an account established under the Plan for
         a Non-employee Director to which cash meeting fees and retainers have
         been or are to be credited in the form of cash.

                  "Change in Control" means any of the following:

                           (i) the Company ceases to be, directly or indirectly,
                  owned of record by at least 1,000 shareholders;

                           (ii) a person, partnership, joint venture,
                  corporation or other entity, or two or more of any of the
                  foregoing acting as a "person" within the meaning of Section
                  13(d)(3) of the 1934 Act, other

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                  than the Company, a majority-owned subsidiary of the Company
                  or an employee benefit plan of the Company or such subsidiary
                  (or such plan's related trust), become(s) the "beneficial
                  owner" (as defined in Rule 13d-3 under the 1934 Act) of 20% or
                  more of the then outstanding voting stock of the Company;

                           (iii) during any period of two consecutive years,
                  individuals who at the beginning of such period constitute the
                  Board (together with any new director whose election by the
                  Board or whose nomination for election by the Company's
                  shareholders was approved by a vote of at least two-thirds of
                  the directors then still in office who either were directors
                  at the beginning of such period or whose election or
                  nomination for election was previously so approved) cease for
                  any reason to constitute a majority of the directors then in
                  office;

                           (iv) all or substantially all of the business of the
                  Company is disposed of pursuant to a merger, consolidation or
                  other transaction in which the Company is not the surviving
                  corporation or the Company combines with another company and
                  is the surviving corporation (unless the shareholders of the
                  Company immediately following such merger, consolidation,
                  combination, or other transaction beneficially own, directly
                  or indirectly, more than 50% of the aggregate voting stock or
                  other ownership interests of (x) the entity or entities, if
                  any, that succeed to the business of the Company or (y) the
                  combined company); or

                           (v) the shareholders of the Company approve a sale of
                  all or substantially all of the assets of the Company or a
                  liquidation or dissolution of the Company.

                  "Code" means the Internal Revenue Code of 1986, as amended
         from time to time.

                  "Committee" means the Compensation Committee (or its
         successor) of the Board.

                  "Common Stock" means the Company's Common Stock, par value
         $1.00 per share.

                  "Company" means Arch Chemicals, Inc., a Virginia corporation,
         and any successor.

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                  "Compensation Account" means the account established under the
         Plan to which a Non-employee Director's compensation is credited,
         including the Cash Account, Stock Account, and such other investment
         accounts as the Committee may establish from time to time pursuant to
         Section 6(d).

                  "Corporate Human Resources" means the Corporate Human
         Resources Department of the Company.

                  "Credit Date" means the first day of each calendar quarter,
         beginning with April 1, 1999.

                  "Distribution" means the distribution of the shares of the
         Company by Olin in a spinoff to Olin's shareholders.

                  "Distribution Date" means the dividend payment date fixed by
         the Olin Board of Directors for the distribution of the shares of
         Common Stock to the public shareholders of Olin.

                  "Excess Retainer" means with respect to a Non-employee
         Director the amount of the full annual cash retainer payable to such
         Non-employee Director from time to time by the Company for service as a
         director in excess of the amount paid in shares of Common Stock, if
         any, pursuant to Section 6(b).

                  "Fair Market Value" means, with respect to a date, on a per
         share or unit basis, (i) with respect to Common Stock or phantom shares
         of Common Stock, the average of the high and the low price of a share
         of Common Stock reported on the consolidated tape of the New York Stock
         Exchange (or such other primary exchange on which the Common Stock is
         traded) ("Exchange") on such date or if the Exchange is closed on such
         date, the next succeeding date on which it is open, (ii) with respect
         to phantom shares of Olin Common Stock, the average of the high and the
         low price of a share of Olin Common Stock reported on the consolidated
         tape of the Exchange on such date or if the Exchange is closed on such
         date, the next succeeding date on which it is open and (iii) with
         respect to other investment vehicles, the closing or unit price or net
         asset value of such vehicle, as the case may be, on such date.

                  "Interest Rate" means the rate of interest equal to the
         Company's before-tax cost of borrowing as determined

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         from time to time by the Chief Financial Officer, the Treasurer or the
         Controller of the Company (or in the event there is no such borrowing,
         the Federal Reserve A1/P1 Composite rate for 90-day commercial paper
         plus 10 basis points, as determined by any such officer) or such other
         rate as determined from time to time by the Board or the Committee.

                  "1999 Non-employee Director" means a Non-employee Director who
         becomes such on or after the Distribution Date but prior to December
         31, 1999, and who was not a non-employee director of Olin.

                  "1997 Plan" means the 1997 Stock Plan for Non-employee
         Directors of Olin Corporation as in effect on the Distribution Date.

                  "l934 Act" means the Securities Exchange Act of 1934, as
         amended from time to time.

                  "Non-employee Director" means a member of the Board who is not
         an employee of the Company or any subsidiary thereof.

                  "Olin" means Olin Corporation, a Virginia corporation.

                  "Olin Common Stock" means shares of common stock of Olin, par
         value $1.00 per share.

                  "Olin Stock Account" means the Stock Account to which phantom
         shares of Olin Common Stock are credited from time to time.

                  "Option" means an option to purchase shares of Common Stock
         granted under Section 6(a)(2).

                  "Performance Shares" means an award of phantom shares or units
         of Common Stock contingent upon the achievement of specified
         performance goals granted under Section 6(a)(3).

                  "Plan" means this Arch Chemicals, Inc. 1999 Stock Plan for
         Non-employee Directors as amended from time to time.

                  "Retirement Date" means the date the Non-employee Director
         ceases to be a member of the Board for any reason.

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                  "Stock Account" means an account established under the Plan
         for a Non-employee Director to which shares of stock have been or are
         to be credited in the form of phantom common stock, including the Olin
         Stock Account and the Arch Stock Account.

         3.       TERM. The Plan shall be effective on the Distribution Date.
Once effective, the Plan shall operate and shall remain in effect until
terminated as provided in Section 9 hereof.

         4.       ADMINISTRATION. Full power and authority to construe,
interpret and administer the Plan shall be vested in the Committee. Decisions of
the Committee shall be final, conclusive and binding upon all parties.

         5.       PARTICIPATION. All Non-employee Directors shall participate in
the Plan.

         6.       GRANTS AND DEFERRALS.

                  (a) Annual Award. Each Non-employee Director who is serving as
such on January 1 shall be credited with the Annual Director Grant on January 1
of each calendar year beginning not earlier than 2000. In the event a person
becomes a Non-employee Director after January 1 of any calendar year beginning
with 2000, such Non-employee Director shall not be credited with the Annual
Director Grant for such year. By December 31 of each year commencing with 1999,
the Board shall determine if the Annual Director Grant to each Non-employee
Director for the next following calendar year shall be determined under (1), (2)
or (3) below (or any combination thereof).

                           (1) Stock Grant. Subject to the terms and conditions
of the Plan, the Annual Director Grant may consist of a grant of phantom shares
of Common Stock. Actual receipt of shares shall be deferred until the
Non-employee Director's Retirement Date unless the Board elects otherwise prior
to the actual grant, in which case the shares will be distributed as soon as
practicable following their grant unless deferred by a Non-employee Director
with the approval of the Board. If the shares are deferred each eligible
Non-employee Director shall receive a credit to his or her Arch Stock Account in
the amount of such shares as of January 1 of the calendar year for which the
award is made. Subject to the approval of the Board, a Non-employee Director may
elect in accordance with Section 6(e) to defer to his or her Arch Stock Account
receipt of all or any portion of such shares to a date or dates on or

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following such Non-employee Director's Retirement Date. Except with respect to
any shares the director has so deferred, certificates representing such shares
shall be delivered to the Non-employee Director (or in the event of death, to
his or her beneficiary designated pursuant to Section 6(h)) as soon as
practicable following the Retirement Date.

                           (2) Stock Options. Subject to the terms and
conditions of the Plan and such additional terms and conditions, consistent with
the terms of the Plan as the Committee shall determine, the Annual Director
Grant may consist of a grant of Options. The exercise price per share of Common
Stock of each Option shall be equal to the Fair Market Value of a share of
Common Stock on the date of a grant. The term of each Option shall be equal to
10 years from the date of grant (whether or not the grantee continues to be a
Non-employee Director for the full term). The Committee shall determine the time
or times at which Options may be exercised in whole or in part (but in no event
shall an Option be exercisable after the expiration of ten years from the date
of its grant) and shall determine the method or methods by which payment of the
exercise price in respect thereto may be made.

                           (3) Performance Shares. Subject to the terms and
conditions of the Plan and such additional terms and conditions, consistent with
the terms of the Plan as the Committee shall determine, the Annual Director
Grant may consist of a grant of Performance Shares. Such award shall confer on
the holder thereof the right to receive one share of Common Stock for each
Performance Share credited to his Stock Account upon the achievement of
specified performance goals during such performance periods as the Committee
shall establish prior to the date of the grant. The performance goals to be
achieved during any performance period and the length of any performance period
shall be determined by the Committee, provided that a performance period shall
be at least one year, subject to Section 6(g) hereof. The Committee may adjust
the performance goals in the event of extraordinary or unusual events.

                  Each eligible Non-employee Director shall receive a credit to
his or her Arch Stock Account in the amount of such Performance Shares as of the
January 1 of the calendar year for which the award is made. Actual receipt of
the shares of Common Stock will be deferred until completion of the performance
period and distribution will occur only if the performance goals are satisfied.
Subject to the approval of the Board, a Non-employee Director may elect in
accordance

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with Section 6(e) to further defer receipt of all or any portion of such Common
Stock. Except with respect to any Performance Shares the Director has so
deferred, certificates representing such shares shall be delivered to the
Non-employee Director (or in the event of death, to his or her beneficiary
designated pursuant to Section 6(h)) as soon as practicable following
satisfaction of the performance goals and completion of the performance period.

                  (b) Annual Retainer Stock Grant. By December 31 of each year
commencing with 1999, the Board shall determine if all or any portion of the
annual retainer for the next following calendar year shall be paid in shares of
Common Stock. Subject to the terms and conditions of the Plan, if the Board
determines for a calendar year that all or a portion of the annual retainer
shall be paid in shares of Common Stock, on January 1 of such year, each
Non-employee Director who is such on such date shall receive a specified number
of shares of Common Stock as determined by the Board. In the event a person
becomes a Non-employee Director beginning in or after 2000 on a date subsequent
to January 1 during a calendar year and has not received the annual stock
retainer for such calendar year, such person, on the first day of the calendar
month following his or her becoming such, shall receive that number of shares
(rounded up to the next whole share in the event of a fractional share) of
Common Stock equal to one-twelfth of the number of shares of the annual retainer
to be paid in Common Stock times the number of whole calendar months remaining
in such calendar year following the date he or she becomes a Non-employee
Director. In the case of a 1999 Non-employee Director, for 1999 such person
shall receive on the first day of the calendar month following his or her
becoming such that number of shares (rounded up to the next whole share) of
Common Stock having an aggregate Fair Market Value equal to $2084 times the
number of whole calendar months remaining in the calendar year after he or she
becomes a 1999 Non-Employee Director. Subject to the approval of the Board
(which approval shall not be required for a 1999 election by a 1999 Non-employee
Director), a Non-employee Director may elect to defer receipt of all or any
portion of such shares in accordance with Section 6(e). Except with respect to
any shares the director has so deferred, certificates representing such shares
shall be delivered to such Non-employee Director as soon as practicable
following the date as of which the shares are awarded.

                  (c) Election to Receive Meeting Fees and Excess Retainer in
Stock in Lieu of Cash. Subject to the terms and conditions of the Plan and the
approval of the Board, a Non-employee Director may elect to receive all or a
portion of the

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director meeting fees and all or a portion of the Excess Retainer payable in
cash by the Company for his or her services as a director for the calendar year
in the form of shares of Common Stock. Such election shall be made in accordance
with Section 6(e). If approved by the Board, the number of shares (rounded up to
the next whole share in the event of a fractional share) for a calendar year
payable to a Non-employee Director who so elects to receive all or a portion of
the Excess Retainer in the form of shares for such year shall be paid on January
1 (or in the case of proration, when the annual stock retainer is to be paid or
credited) equal to the amount of Excess Retainer which has been elected to be
paid in shares divided by the Fair Market Value per share on January 1 of such
calendar year (or in the case of a Non-employee Director who becomes such after
January 1, on the first day of the calendar month following the day such new
Non-employee Director became such). If approved by the Board, the number of
shares (rounded up to the next whole share in the event of a fractional share)
for a calendar quarter payable to a Non-employee Director who so elects to
receive meeting fees in the form of shares shall be equal to the aggregate
amount on the Credit Date following such quarter of the director meeting fees
which have been earned in such quarter and which are elected to be paid in
shares divided by the Fair Market Value per share of Common Stock on such Credit
Date. Except with respect to any shares the director has deferred, certificates
representing such shares shall be delivered to the Non-employee Director as soon
as practicable following the date as of which the Excess Retainer and/or meeting
fees would have been paid in cash absent an election hereunder. Notwithstanding
anything in the Plan to the contrary, the approval of the Board shall not be
required for any 1999 election made by a 1999 Non-employee Director.

                  (d) Deferrals of Meeting Fees and Excess Retainer. Subject to
the terms and conditions of the Plan and the approval of the Board, a
Non-employee Director may elect to defer all or a portion of the shares payable
under Section 6(c) and all or a portion of the director meeting fees and Excess
Retainer payable in cash by the Company for his or her service as a director for
the calendar year. The amount of the Excess Retainer deferred in cash shall be
credited on January 1 (or in the case of proration, on the first day of the next
calendar month following the day such new Non-employee Director becomes such).
Such election shall be made in accordance with Section 6(e). A Non-employee
Director who elects to so defer shall have any deferred shares deferred in the
form of shares of Common Stock and any deferred cash fees and retainer deferred
in the form of cash; provided prior Board approval shall be required for
deferrals in the form of

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phantom shares of Common Stock. Notwithstanding any thing in the Plan to the
contrary, the approval of the Board shall not be required for any 1999 election
made by a 1999 Non-employee Director. The Committee and the Administrator each
may establish from time to time other types of Compensation Accounts reflecting
different investment options. Each Non-employee Director's Compensation Account
shall be credited (or debited) periodically with income (or loss) based on a
hypothetical investment in any one or more of the investment options available
under the Plan, as prescribed by the Plan, the Committee or Corporate Human
Resources. Gains, losses and other elements of determining value shall be
determined substantially on the basis of a hypothetical investment in the
various investment options, as determined and applied in the manner deemed
appropriate by the Committee or Corporate Human Resources.

                  (e) Elections.

                           (1) Deferrals. All elections under Sections 6(a),
         6(b), 6(c), 6(d), 6(e)(2) and 6(e)(3) shall (A) be made in writing and
         delivered to the Secretary of the Company and (B) be irrevocable. All
         Non-employee Director elections for payments in cash or stock or for
         deferrals shall be made before January 1 of the year in which the
         shares of Common Stock or director's fees and retainer are to be earned
         (or, in the case of an individual who becomes a Non-employee Director
         during a calendar year, prior to the date of his or her election as a
         director). Deferral elections shall also (A) specify the portions (in
         25% increments) to be deferred and (B) specify the future date or dates
         on which deferred amounts are to be paid, or the future event or events
         upon the occurrence of which the deferred amounts are to be paid, and
         the method of payment (lump sum or annual installments (up to 10)).
         However, a Non-employee Director may elect to defer all of his or her
         cash dividends on the Stock Account in whole and not in part (with the
         prior approval of the Board if required by Section 16(b) of the 1934
         Act) and all of his or her interest on the Cash Account in whole but
         not in part. Installment payments from an Account shall be equal to the
         Account balance (expressed in shares in the case of the Stock Account,
         otherwise the cash value of the Account) at the time of the installment
         payment times a fraction, the numerator of which is one and the
         denominator of which is the number of installments not yet paid.
         Fractional shares to be paid in any installment shall be rounded up to
         the next whole share.

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         In the event of an election under Section 6(c) for director meeting
         fees or Excess Retainer to be paid in shares of Common Stock, the
         election shall specify the portion (in 25% increments) to be so paid.
         Any change with respect to the terms of a Non-employee Director's
         election for (A) amount or form of any future deferral or the form of
         payment of any director compensation hereunder may be made at any time
         prior to such compensation being earned (and in the case of quarterly
         fees, prior to the start of the quarter in which the fees are to be
         earned) and (B) the timing (which timing may not accelerate a
         distribution date) or amount of payments from any Account shall only be
         effective if made at least six months prior to the payout and in the
         calendar year prior to the calendar year payout is to occur.

                           (2) Stock Account. On the Credit Date (or in the case
         of a proration, on the first day of the appropriate calendar month), a
         Non-employee Director who has deferred shares under Sections 6(b) or
         6(d) shall receive a credit to his or her Stock Account. The amount of
         such credit shall be the number of shares so deferred (rounded to the
         next whole share in the event of a fractional share). A Non-employee
         Director may elect to defer the cash dividends paid on his or her Stock
         Account in accordance with Section 6(e)(1).

                           (3) Other Accounts. On the Credit Date or in the case
         of the Excess Retainer, on the day on which the Non-employee Director
         is entitled to receive such Excess Retainer, a Non-employee Director
         who has deferred cash fees and/or the Excess Retainer under Section
         6(d) in the form of cash shall receive a credit to his or her
         Compensation Account. The amount of the credit shall be the dollar
         amount of such Director's meeting fees earned during the immediately
         preceding quarterly period or the amount of the Excess Retainer to be
         paid for the calendar year, as the case may be, and in each case,
         specified for deferral. A Non-employee Director may elect to defer
         interest paid on his or her Cash Account in accordance with Section
         6(e)(1).

                           (4) Dividends and Interest. Each time a cash dividend
         is paid on Common Stock or Olin Common Stock, a Non-employee Director
         who has shares of such stock (other than shares attributable to
         Performance Shares) credited to his or her Stock Account shall be paid
         on the dividend payment date such cash dividend in an amount equal to
         the product of the number of shares credited to the Non-

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         employee Director's Arch Stock Account or Olin Stock Account, as the
         case may be, on the record date for such dividend times the dividend
         paid per share unless the director has elected to defer such dividend
         to his or her Stock Account as provided herein, in which case the
         Non-employee Director shall receive a credit for such dividends on the
         dividend payment date to his or her Arch Stock Account or Olin Stock
         Account, as the case may be. The amount of the dividend credit shall be
         the number of shares (rounded to the nearest one-thousandth of a share)
         of Common Stock determined by multiplying the dividend amount per share
         by the number of shares credited to such director's applicable Stock
         Account as of the record date for the dividend and dividing the product
         by the Fair Market Value per share on the dividend payment date. At the
         election of the Board, dividend equivalents (determined as described
         above) shall also be paid with respect to Performance Shares held in a
         Non-employee Director's Arch Stock Account; provided, however, that
         such dividend equivalents shall be automatically deferred until, when
         and if the underlying Performance Shares are distributed in the form of
         Common Stock.

                           A Non-employee Director who has a Cash Account shall
         be paid directly on each Credit Date interest on such account's balance
         at the end of the preceding quarter, payable at a rate equal to the
         Interest Rate in effect for such preceding quarter unless with the
         approval of the Board, such Non-employee Director has elected to defer
         such interest to his or her Cash Account, in which case such interest
         shall be credited to such Cash Account on the Credit Date.

                           Other Compensation Accounts shall be credited with
         income (or loss), including dividends and interest, if appropriate,
         periodically in each case as appropriate based on and consistent with
         the particular hypothetical investment option as the Committee or
         Corporate Human Resources determines from time to time. Such credits
         shall be deferred to the particular Compensation Account.

                           (5) Payouts. All Compensation Accounts (other than
         the Arch Stock Account) will be paid out in cash, and the Arch Stock
         Accounts shall be paid out in shares of Common Stock unless the
         Non-employee director elects otherwise; provided that with respect to
         any and all amounts or grants credited to the Arch Stock Accounts after
         December 31, 2001, amounts so credited (and any portions thereof
         including dividend equivalents credited) may, if the Board so
         specifies, be payable only in cash

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         upon payout at the then Fair Market Value (except as otherwise provided
         in Section 6(g)). Cash amounts and certificates representing shares
         credited to the Arch Stock Account to be distributed in Common Stock
         shall be delivered to the Non-employee Director as soon as practicable
         following the termination of the deferral and consistent therewith.

                           (6) Transfers Among Accounts. Non-employee Directors
         may transfer deferred account balances representing deferred meeting
         fees and deferrals of the Excess Retainer (including earnings thereon)
         between and among the various Compensation Accounts from time to time
         and in such amounts in accordance with procedures established from time
         to time by Corporate Human Resources; provided no amounts may be
         transferred into the Olin Stock Account and no amounts may be
         transferred to a Compensation Account which has a scheduled
         distribution date that is earlier than the Compensation Account from
         which the amount is being transferred. The Administrator may establish
         from time to time blackout periods during which no transfers may occur
         among all or certain Compensation Accounts and investment vehicles.
         Additionally, Non-employee Directors may not transfer amounts out of or
         into the Arch Stock Account without complying with Section 16(b) of the
         1934 Act.

                  (f) No Stock Rights. Except as expressly provided herein, the
deferral of shares of Common Stock into a Stock Account shall confer no rights
upon such Non-employee Director, as a shareholder of the Company or otherwise,
with respect to the shares held in such Stock Account, but shall confer only the
right to receive such shares credited as and when provided herein. A
Non-employee Director who has been granted an Option hereunder shall have no
rights as a shareholder until such time as his or her Option is exercised.

                  (g) Change in Control. Notwithstanding anything to the
contrary in this Plan or any election, in the event a Change in Control occurs,
(1) all Performance Shares shall become vested and deemed earned in full
notwithstanding that the applicable performance cycle shall not have been
completed, and (2) amounts and shares credited to all Compensation Accounts
(including interest accrued to the date of payout on the Cash Account) shall be
promptly distributed to Non-employee Directors except that the Arch Stock
Account shall be paid out in cash and not in the form of shares of Common Stock.
For this purpose, the cash value of the amount in the Arch Stock Account shall
be determined by multiplying the number of shares held in the Arch Stock Account
by the

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higher of (i) the highest Fair Market Value on any date within the period
commencing 30 days prior to such Change in Control and ending on the date of the
Change in Control, or (ii) if the Change in Control occurs as a result of a
tender or exchange offer or consummation of a corporate transaction, then the
highest price paid per share of Common Stock pursuant thereto.

                  (h) Beneficiaries. A Non-employee Director may designate at
any time and from time to time a beneficiary for his or her Compensation
Accounts in the event his or her Compensation Accounts may be paid out following
his or her death. Such designation shall be in writing and must be received by
the Company prior to the death to be effective.

                  (i) 1997 Plan Accounts. As of the Distribution Date, the cash
and stock accounts of each Non-employee Director who immediately prior to the
Distribution Date was a participant in the 1997 Plan shall be transferred from
the 1997 Plan to this Plan after giving effect to the adjustment for the
Distribution in accordance with Section 6(k) of the 1997 Plan as in effect on
the Distribution Date. Such amounts shall be transferred, in the case of an
account denominated in cash, to the Cash Account, in the case of a transferred
account denominated in Olin Common Stock, to the Olin Stock Account, and in the
case of an account denominated in Common Stock to the Common Stock Account.

                  Shares credited to the Arch Stock Account pursuant to this
paragraph 6(i) shall be treated as follows: (i) to the extent such shares
represent a dividend on shares of Olin Common Stock credited pursuant to
paragraph 6(a)(1) of the 1997 Plan (or shares arising from dividend equivalents
thereon), such shares shall be deemed credited pursuant to paragraph 6(a) of the
Plan, (ii) to the extent such shares represent a dividend on shares of Olin
Common Stock credited pursuant to paragraph 6(b) of the 1997 Plan (or shares
arising from dividend equivalents thereon), such shares shall be deemed credited
pursuant to paragraph 6(b) of this Plan, and (iii) to the extent such shares
represent a dividend on shares of Olin Common Stock credited under paragraph
6(c) of the 1997 Plan (or shares arising from dividend equivalents thereon),
such shares shall be deemed credited pursuant to paragraph 6(a)(1) of the Plan.
The most recent prior elections and beneficiary designations applicable to the
1997 Plan shall govern this Plan unless changed subsequent to the Distribution
Date or inconsistent with this Plan. Approval of the Board shall not be required
for any such elections for 1999 but shall be required in accordance with the
terms of this Plan for years after 1999.

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                  (j) Olin Stock Account. Except as provided in Section 6(e)(4)
with respect to dividends or in Section 8, no additional contributions or
additions may be made to a Non-Employee Director's Olin Stock Account after the
Distribution Date.

         7.       LIMITATIONS AND CONDITIONS.

                  (a) Total Number of Shares. The total number of shares of
Common Stock that may be issued to Non-employee Directors under the Plan is
150,000. Such total number of shares may consist, in whole or in part, of
authorized but unissued shares. The foregoing number may be increased or
decreased by the events set forth in Section 8 below. No fractional shares shall
be issued hereunder. In the event a Non-employee Director is entitled to a
fractional share, such share amount shall be rounded upward to the next whole
share amount.

                  (b) No Additional Rights. Nothing contained herein shall be
deemed to create a right in any Non-employee Director to remain a member of the
Board, to be nominated for reelection or to be reelected as such or, after
ceasing to be such a member, to receive any cash or shares of Common Stock under
the Plan which are not already credited to his or her accounts.

         8.       STOCK ADJUSTMENTS. In the event of any merger, consolidation,
stock or other non-cash dividend, extraordinary cash dividend, split-up,
spin-off, combination or exchange of shares or recapitalization or change in
capitalization, or any other similar corporate event, the Committee may make
such adjustments in (i) the aggregate number of shares of Common Stock that may
be issued under the Plan as set forth in Section 7(a) and the number of shares
and/or Options that may be issued to a Non-employee Director with respect to any
year as set forth in Section 6(a) and the number of shares of Olin Common Stock
or Arch Common Stock, as the case may be, held in a Stock Account, (ii) the
class of shares that may be issued under the Plan, (iii) the amount and type of
payment that may be made in respect of unpaid dividends on shares of Common
Stock or Olin Common Stock whose receipt has been deferred pursuant to Section
6(e), and (iv) the exercise price with respect to any award of Options or, if
the Committee deems it appropriate, make provision for cash payment to the
holder of an outstanding Option, as the Committee shall deem appropriate in the
circumstances. The determination by the Committee as to the terms of any of the
foregoing adjustments shall be

<PAGE>

                                                                              15

final, conclusive and binding for all purposes of the Plan.

         9.       AMENDMENT AND TERMINATION. This Plan may be amended, suspended
or terminated by action of the Board. No termination of the Plan shall adversely
affect the rights of any Non-employee Director with respect to any amounts
otherwise payable or credited to his or her Compensation Accounts.

         10.      NONASSIGNABILITY. No right to receive any payments under the
Plan or any amounts credited to a Non-employee Director's Compensation Account
shall be assignable or transferable by such Non-employee Director other than by
will or the laws of descent and distribution or pursuant to a domestic relations
order. The designation of a beneficiary under Section 6(h) by a Non-employee
Director does not constitute a transfer.

         11.      UNSECURED OBLIGATION. Benefits payable under this Plan shall
be an unsecured obligation of the Company. Nothing herein shall prohibit the
establishment of a grantor or rabbi trust with respect to the Plan.

         12.      SECTION 16b COMPLIANCE. It is the intention of the Company
that all transactions under the Plan be exempt from liability imposed by Section
16(b) of the 1934 Act. Therefore, if any transaction under the Plan is found not
to be in compliance with an exemption from such Section 16(b), the provision of
the Plan governing such transaction shall be deemed amended so that the
transaction does so comply and is so exempt, to the extent permitted by law and
deemed advisable by the Committee, and in all events the Plan shall be construed
in favor of its meeting the requirements of an exemption.

         13.      CREDIT AND GRANTS. Amounts to be credited or granted hereunder
shall be granted or credited on the date specified if such date is a business
day; otherwise, on the next succeeding business day.