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                                                                    Exhibit 10.9

                              AMENDED AND RESTATED
                          CHANGE IN CONTROL AGREEMENT

          THIS AMENDED AND RESTATED CHANGE IN CONTROL AGREEMENT (this
"Agreement") is made as of October 26, 2000, between OSCA, Inc., a Delaware
corporation (the "Company") and, together with any of its subsidiaries or
successors in interest, including a successor in a Change in Control (as
defined below), the "Employer"), and Robert L. Hollier ("Executive"). This
Agreement amends and restates the Change in Control Agreement dated June 20,
2000, between the Company and the Executive (the "Original Agreement").

          WHEREAS, Executive provides valuable services to the Company and the
Company has determined that it would be in the Company's interest to provide
Executive certain assurances regarding Executive's treatment in the event of a
Change in Control; and

          WHEREAS, Executive desires to secure such assurances;

          NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties hereto agree as follows:

     1.   Severance Payment.

          (a)  If, subject to the conditions set forth in Section 1(b) below,
Executive's employment with the Employer is terminated under the circumstances
contemplated by Section 1(b), Employer shall pay Executive a lump sum severance
payment (the "Severance Payment") equal to three times Executive's Annual
Compensation as in effect prior to the Change in Control.

          (b)  Executive shall only be entitled to the Severance Payment if: (i)
the Company has undergone a Change in Control prior to the fifth anniversary of
the date of this Agreement; and (ii) Executive makes himself immediately
available for continued employment by the Company's successor in interest in
such Change in Control; and (iii) (A) such successor in interest elects not to
continue Executive's employment in connection with such Change in Control or (B)
prior to the first anniversary of such Change in Control, Executive's employment
with the Employer is terminated by the Employer without Cause or Executive
resigns from the Employer with Good Reason; and (iv) Executive executes a
general release of the Employer in the form attached hereto as Annex A. For the
avoidance of doubt, if Executive's employment with the Employer terminates under
any other circumstances, including by reason of death, disability, retirement,
resignation without Good Reason or termination by the Employer for Cause,
Executive shall not be entitled to any severance payment whatsoever.

          (c)  The Employer shall pay the Severance Payment to Executive in
cash or wire transfer of immediately available funds within 30 days of the
termination of his employment under the circumstances contemplated by Section
1(b). If Executive dies after such termination but before

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the Severance Payment is paid in full, Employer shall pay the Severance Payment
to Executive's legal heir or estate. The Severance Payment shall be subject to
all required tax withholding by the Employer.

               (d)  In addition to the payment provided under Section 1(a)
hereof, if Executive's employment with the Employer is terminated under the
circumstances contemplated by Section 1(b), all outstanding stock options
previously granted to Executive, and not yet expired, will become fully and
immediately vested and exercisable by Executive on the date of termination of
Executive's employment with Employer and for such period of time thereafter as
shall be permitted pursuant to the applicable stock option plan and stock award
agreements.

               2.   No Guarantee of Employment.  Executive hereby acknowledges
and agrees that nothing in this Agreement constitutes a guarantee or assurance
of continued employment with the Employer and that his only rights under this
Agreement are to payment of the Severance Payment and immediate vesting of stock
options in accordance with the terms of this Agreement.

               3.   Certain Definitions.  The following capitalized terms used
in this Agreement have the meanings set forth below:

               (a)  "Annual Compensation" means Executive's annual base salary
as in effect immediately prior to the Change in Control, plus an amount equal to
all other amounts paid to Executive as wages, bonuses, commissions, profit
sharing or other cash compensation for services rendered during the twelve month
period immediately prior to the Change in Control.

               (b)  "Cause" means (i) the commission of a felony or other crime
involving moral turpitude or the commission of any other act or omission
involving dishonesty, disloyalty or fraud with respect to the Employer or any of
its Subsidiaries or any of their customers or suppliers, (ii) reporting to work
under the influence of alcohol or illegal drugs, the use of illegal drugs
(whether or not at the workplace) or other repeated conduct causing the Employer
or any of its Subsidiaries substantial public disgrace or disrepute or economic
harm, or (iii) substantial and repeated failure to perform duties as reasonably
directed by the Employer's Board of Directors.

               (c)  a "Change in Control" shall be deemed to have occurred if
the conditions set forth in any one of the following paragraphs shall have been
satisfied:

               (i)  any "person" (as such term is used in Section 13(d) and
          14(d) of the Securities Exchange Act of 1934, as amended (the
          "Exchange Act")) other than (i) the Company, (ii) a trustee or other
          fiduciary holding securities under an employee benefit plan of the
          Company, (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 shares of the
          Company (any such person is hereinafter referred to as 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
          (not including in the securities beneficially owned by such Person any
          securities acquired directly from the Company) representing 20% or
          more of the combined voting


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power of the Company's then outstanding securities and GLC holds beneficial
ownership, directly or indirectly, of securities of the Company representing
less than 51% of the combined voting power of the Company's then outstanding
securities excluding any Person who becomes such a beneficial owner in
connection with a transaction described in clause (A) of paragraph (ii) below;

     (ii)      there is consummated a merger or consolidation of the Company or
any direct or indirect subsidiary of the Company with or into any other
corporation, other than (A) a merger or consolidation which results in the
directors of the Company immediately prior to such merger or consolidation
continuing to constitute at least a majority of the Board of Directors of the
Company, the surviving entity or any parent thereof or (B) a merger or
consolidation effected to implement a recapitalization of the Company (or
similar transaction) in which (x) GLC retains beneficial ownership, directly or
indirectly of at least 51% of the voting power of the Company's then
outstanding securities, or (y) no Person is or becomes the beneficial owner,
directly or indirectly, of securities of the Company (not including in the
securities beneficially owned by such Person any securities acquired directly
from the Company) representing 20% or more of the combined voting power of the
Company's then outstanding securities (regardless of whether GLC continues to
own beneficial ownership of any of the Company's securities);

     (iii)     the stockholders of the Company approve any plan or proposal for
the liquidation or dissolution of the Company or there is consummated an
agreement for the sale or disposition by the Company of all or substantially
all the Company's assets, other than a sale or disposition by the Company of
all or substantially all of the Company's assets to an entity, at least a
majority of whose directors were directors of the Company immediately prior to
such sale or disposition; or

     (iv)      during any period of two consecutive years (not including any
period prior to the date of this Agreement), individuals who at the beginning of
such period constitute the Board of Directors of the Company and any new
director (other than a director whose initial assumption of office is in
connection with an actual or threatened election contest, including but not
limited to a consent solicitation, relating to the election of directors of the
Company) whose appointment or election by the Board of Directors of the Company
or nomination for election by the Company's stockholders was approved or
recommended 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
appointment, election or nomination for election was previously so approved,
cease for any reason to constitute a majority thereof.

     Where a Change in Control results from a series of related transactions,
the Change in Control shall be deemed to have occurred on the date of the
consummation of the first such transaction.

     Notwithstanding any other provision hereof, a Change in Control shall not
be deemed to have occurred by virtue of the consummation of any transaction or
series of integrated transactions immediately following which the record
holders of the common stock of the Company immediately



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prior to such transaction or series of transactions continue to have
substantially the same proportionate ownership in an entity which owns all or
substantially all of the assets of the Company immediately following such
transaction or series of transactions.

          (d)       Executive shall be deemed to have terminated his employment
with the Employer with "Good Reason" if, prior to such termination:

          (i)       the Employer has reduced Executive's base salary or rate of
     compensation as in effect immediately prior to the Change in Control; or

          (ii)      the Employer has assigned Executive duties and
     responsibilities substantially different than those in effect immediately
     prior to the Change in Control; or

          (iii)     the Employer requires Executive to change the location of
     his job or office to a location more than 40 miles from the location in
     effect immediately prior to the Change in Control provided that such new
     location is not closer to Executive's primary residence; or

          (iv)      the Employer fails to provide Executive with pension plans,
     401(k) plans, life insurance plans, health, accident or disability plans,
     or other health, welfare and retirement benefits materially equal to those
     in effect immediately prior to the Change in Control.

          (e)       "GLC" means Great Lakes Chemical Corporation, a Delaware
corporation.

          (f)       "Subsidiary" means any corporation or other entity of which
the securities or other ownership interests having the voting power to elect a
majority of the board of directors or other governing body are, at the time of
determination, owned by the Employer, directly or through one of more
Subsidiaries.

          4.        Severability. Whenever possible, each provision of this
Agreement shall be interpreted in such manner as to be effective and valid
under applicable law, but if any provision of this Agreement is held to be
invalid, illegal or unenforceable in any respect under any applicable law or
rule in any jurisdiction, such invalidity, illegality or unenforceability shall
not affect any other provision or any action in any other jurisdiction, but
this Agreement shall be reformed, construed and enforced in such jurisdiction
as if such invalid, illegal or unenforceable provision had never been contained
herein.

          5.        Complete Agreement. Subject to any rights of Executive
pursuant to applicable law, applicable benefit plans and stock award
agreements, this Agreement embodies the complete agreement and understanding
among the parties and supersedes and preempts any prior understandings,
agreements or representations by or among the parties, written or oral, which
may have related to the subject matter hereof in any way (including, without
limitation, the Original Agreement and the Transition Payment Agreement between
the parties hereto, dated September 17, 1999); provided, however, that
Executive's Great Lakes Change of Control Agreement, dated March 5, 1997 (the
"Great Lakes Agreement") shall not be preempted or superseded by this Agreement.
In the event that the Executive becomes entitled to receive concurrent
Severance Payments under


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both this Agreement and the Great Lakes Agreement, then the Great Lakes
Agreement shall preempt and supersede this Agreement and Executive shall only be
entitled to receive Severance Payments under the Great Lakes Agreement.

     6.   No Strict Construction. The language used in this Agreement shall be
deemed to be the language chosen by the parties hereto to express their mutual
intent, and no rule of strict construction shall be applied against any party.

     7. Counterparts. This Agreement may be executed in separate counterparts,
each of which is deemed to be an original and all of which taken together
constitute one and the same agreement.

     8. Successors and Assigns. This Agreement is intended to bind and inure to
the benefit of and be enforceable by Executive, the Company and their respective
heirs, successors and assigns, except that Executive may not assign his rights
or delegate his duties or obligations hereunder without the prior written
consent of the Company.

     9. Choice of Law. All issues and questions concerning the construction,
validity, enforcement and interpretation of this Agreement and the annex
attached hereto shall be governed by, and construed in accordance with, the laws
of the State of Delaware, without giving effect to any choice of law or conflict
of law rules or provisions (whether of the State of Delaware or any other
jurisdiction) that would cause the application of the laws of any jurisdiction
other than the State of Delaware.

     10. Amendment and Waiver. The provisions of this Agreement may be amended
or waived only with the prior written consent of the Employer and Executive, and
no course of conduct or course of dealing or failure or delay by any party
hereto in enforcing or exercising any of the provisions of this Agreement shall
affect the validity, binding effect or enforceability of this Agreement or be
deemed to be an implied waiver of any provision of this Agreement.

     IN WITNESS WHEREOF, the parties hereto have executed this Change in Control
Agreement as of the date first written above.

                              OSCA INC.

                              /s/ MARK P. BULRISS
                              ------------------------------------------
                              By:  Mark P. Bulriss
                              Its: Chairman of the Board of Directors




                              EXECUTIVE

                              /s/ ROBERT L. HOLLIER
                              ------------------------------------------
                              By:  Robert L. Hollier


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                                                                         Annex A


                                GENERAL RELEASE

     I, ______________________, in consideration of and subject to the
performance by OSCA, Inc., a Delaware corporation or its successor in interest
(together with its subsidiaries, the "Company"), of its material obligations
under the Amended and Restated Change in Control Agreement, dated as of
____________, 2000 (the "Agreement"), do hereby release and forever discharge
as of the date hereof the Company and all present and former directors,
officers, agents, representatives, employees, successors and assigns or
predecessors of the Company and its direct or indirect owners (collectively,
the "Released Parties") to the extent provided below.

1.   I understand that any payments or benefits paid or granted to me under
     Section 1 of the Agreement represent, in part, consideration for signing
     this General Release and are not salary, wages or benefits to which I was
     already entitled. I understand and agree that I will not receive the
     payments and benefits specified in Section 1 of the Agreement unless I
     execute this General Release and do not revoke this General Release within
     the time period permitted hereafter or breach this General Release.

2.   Except as provided in paragraph 4 below, I knowingly and voluntarily
     release and forever discharge the Company and the other Released Parties
     from any and all claims, controversies, actions, causes of action,
     cross-claims, counter-claims, demands, debts, compensatory damages,
     liquidated damages, punitive or exemplary damages, other damages, claims
     for costs and attorney's fees, or liabilities of any nature whatsoever in
     law and in equity, both past and present (through the date of this General
     Release) and whether known or unknown, suspected, or claimed against the
     Company or any of the Released Parties which I, my spouse, or any of my
     heirs, executors, administrators or assigns, may have, which arise out of
     or are connected with my employment with, or my separation from, the
     Company (including, but not limited to, any allegation, claim or violation,
     arising under; Title VII of the Civil Rights Act of 1964, as amended; the
     Civil Rights Act of 1991; the Age Discrimination in Employment Act of 1967,
     as amended (including the Older Workers Benefit Protection Act); the Equal
     Pay Act of 1963, as amended; the Americans with Disabilities Act of 1990;
     the Family and Medical Leave Act of 1993; the Civil Rights Act of 1866, as
     amended; the Worker Adjustment Retraining and Notification Act; the
     Employee Retirement Income Security Act of 1974; any applicable Executive
     Order Programs; the Fair Labor Standards Act; or their state or local
     counterparts; or under any other federal, state or local, civil or human
     rights law, or under any other local, state, or federal law, regulation or
     ordinance; or under any public policy, contract or tort, or under common
     law; or arising under any policies, practices or procedures of the Company;
     or any claim for wrongful discharge, breach of contract, infliction of
     emotional distress, defamation; or any claim for costs, fees, or other
     expenses, including attorneys' fees incurred in these matters) (all of the
     foregoing collectively referred to herein as the "Claims").


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3.   I represent that I have made no assignment or transfer of any right,
     claim, demand, cause of action or other matter covered by paragraph 2
     above.

4.   I agree that this General Release does not waive or release any (i) rights
     or claims that I may have under the Age Discrimination in Employment Act of
     1967 which arise after the date I execute this General Release; or (ii) any
     claims with respect to accrued benefits under employee benefit plans
     maintained by the Company or any claims arising from the Company's
     obligation to provide any benefits (other than severance benefits) to
     which I may be entitled under applicable plan provisions (as amended from
     time to time) based on the date of termination of employment with the
     Company. In addition, the release of all claims shall not affect currently
     pending workers compensation proceedings or claims, nor the right of either
     party to enforce the terms of the Agreement and this General Release. I
     acknowledge and agree that my separation from employment with the Company
     in compliance with the terms of the Agreement shall not serve as the basis
     for any claim or action (including, without limitation, any claim under the
     Age Discrimination in Employment Act of 1967).

5.   In signing this General Release, I acknowledge and intend that it shall be
     effective as a bar to each and every one of the Claims hereinabove
     mentioned or implied. I expressly consent that this General Release shall
     be given full force and effect according to each and all of its express
     terms and provisions, including those relating to unknown and unsuspected
     Claims (notwithstanding any state statute that expressly limits the
     effectiveness of a general release of unknown, unsuspected and
     unanticipated Claims), if any, as well as those relating to any other
     Claims hereinabove mentioned or implied. I acknowledge and agree that this
     waiver is an essential and material term of this General Release and that
     without such waiver the Company would not have agreed to the terms of the
     Agreement. I further agree that in the event I should bring a Claim seeking
     damages against the Company, or in the event I should seek to recover
     against the Company in any Claim brought by a governmental agency on my
     behalf, this General Release shall serve as a complete defense to such
     Claims. I further agree that I am not aware of any pending charge or
     complaint of the type described in paragraph 2 as of the execution of this
     General Release.

6.   I agree that neither this General Release, nor the furnishing of the
     consideration for this General Release, shall be deemed or construed at any
     time to be an admission by the Company, any Released Party or myself of any
     improper or unlawful conduct.

7.   I agree that I will forfeit all amounts payable by the Company pursuant to
     the Agreement if I challenge the validity of this General Release. I also
     agree that if I violate this General Release by suing the Company or the
     other Released Parties for claims waived by this General Release, I will
     pay all costs and expenses of defending against the suit incurred by the
     Released Parties, including reasonable attorneys' fees, and return all
     payments received by me pursuant to the Agreement.

8.   I agree that this General Release is confidential and agree not to disclose
     any information regarding the terms of this General Release, except to my
     immediate family and any tax,





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     legal or other counsel I have consulted regarding the meaning or effect
     hereof or as required by law, and I will instruct each of the foregoing not
     to disclose the same to anyone.

9.   Any non-disclosure provision in this General Release does not prohibit or
     restrict me (or my attorney) from responding to any inquiry about this
     General Release or its underlying facts and circumstances by the Securities
     and Exchange Commission (SEC), the National Association of Securities
     Dealers, Inc. (NASD), any other self-regulatory organization or
     governmental entity.

10.  I agree to reasonably cooperate with the Company in any internal
     investigation or administrative, regulatory, or judicial proceeding. I
     understand and agree that my cooperation may include, but not be limited
     to, making myself available to the Company upon reasonable notice for
     interviews and factual investigations; appearing at the Company's request
     to give testimony without requiring service of a subpoena or other legal
     process; volunteering to the Company pertinent information; and turning
     over to the Company all relevant documents which are or may come into my
     possession all at times and on schedules that are reasonably consistent
     with my other permitted activities and commitments. I understand that in
     the event the Company asks for my cooperation in accordance with this
     provision, the Company will reimburse me solely for reasonable travel
     expenses, including lodging and meals, upon my submission of receipts.

11.  Notwithstanding anything in this General Release to the contrary, this
     General Release shall not relinquish, diminish, or in any way affect any
     rights or claims arising out of any breach by the Company or by any
     Released Party of the Agreement.

12.  Whenever possible, each provision of this General Release shall be
     interpreted in, such manner as to be effective and valid under applicable
     law, but if any provision of this General Release is held to be invalid,
     illegal or unenforceable in any respect under any applicable law or rule in
     any jurisdiction, such invalidity, illegality or unenforceability shall not
     affect any other provision or any other jurisdiction, but this General
     Release shall be reformed, construed and enforced in such jurisdiction as
     if such invalid, illegal or unenforceable provision had never been
     contained herein.

BY SIGNING THIS GENERAL RELEASE, I REPRESENT AND AGREE THAT:

(a)  I HAVE READ IT CAREFULLY;

(b)  I UNDERSTAND ALL OF ITS TERMS AND KNOW THAT I AM GIVING UP IMPORTANT
     RIGHTS, INCLUDING BUT NOT LIMITED TO, RIGHTS UNDER THE AGE DISCRIMINATION
     IN EMPLOYMENT ACT OF 1967, AS AMENDED, TITLE VII OF THE CIVIL RIGHTS ACT OF
     1964, AS AMENDED; THE EQUAL PAY ACT OF 1963, THE AMERICANS WITH
     DISABILITIES ACT OF 1990; AND THE EMPLOYEE RETIREMENT INCOME SECURITY ACT
     OF 1974, AS AMENDED;

(c)  I VOLUNTARILY CONSENT TO EVERYTHING IN IT;

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(d)  I HAVE BEEN ADVISED TO CONSULT WITH AN ATTORNEY BEFORE EXECUTING IT AND I
     HAVE DONE SO OR, AFTER CAREFUL READING AND CONSIDERATION I HAVE CHOSEN NOT
     TO DO SO OF MY OWN VOLITION;

(e)  I HAVE HAD AT LEAST 21 DAYS FROM THE DATE OF MY RECEIPT OF THIS RELEASE
     SUBSTANTIALLY IN ITS FINAL FORM ON            ,          TO CONSIDER IT AND
     THE CHANGES MADE SINCE THE     ,       VERSION OF THIS RELEASE ARE NOT
     MATERIAL AND WILL NOT RESTART THE REQUIRED 21-DAY PERIOD;

(f)  THE CHANGES TO THE AGREEMENT SINCE         ,         EITHER ARE NOT
     MATERIAL OR WERE MADE AT MY REQUEST.

(g)  I UNDERSTAND THAT I HAVE SEVEN DAYS AFTER THE EXECUTION OF THIS RELEASE TO
     REVOKE IT AND THAT THIS RELEASE SHALL NOT BECOME EFFECTIVE OR ENFORCEABLE
     UNTIL THE REVOCATION PERIOD HAS EXPIRED;

(h)  I HAVE SIGNED THIS GENERAL RELEASE KNOWINGLY AND VOLUNTARILY AND WITH THE
     ADVICE OF ANY COUNSEL RETAINED TO ADVISE ME WITH RESPECT TO IT; AND

(i)  I AGREE THAT THE PROVISIONS OF THIS GENERAL RELEASE MAY NOT BE AMENDED,
     WAIVED, CHANGED OR MODIFIED EXCEPT BY AN INSTRUMENT IN WRITING SIGNED BY AN
     AUTHORIZED REPRESENTATIVE OF THE COMPANY AND BY ME.



DATE:               ,

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