Document:

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                                                                  Exhibit 10.9
                            TETRA TECHNOLOGIES, INC.
                           DIRECTOR STOCK OPTION PLAN

1. Purpose

      The purpose of the TETRA Technologies, Inc. Director Stock Option Plan
("Plan") is to enable TETRA Technologies, Inc. ("Company") to attract and retain
qualified individuals to serve as directors of the Company and to align the
interests of such individuals more closely with the interest of the Company's
stockholders by facilitating their acquisition of shares of Common Stock.

2. Definitions

      Unless the context indicates otherwise, the following terms have the
meanings set forth below:

      "Annual Grant Date" means January 1 of each year commencing with 1997.

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

      "Common Stock" means the Common Stock, par value $0.01 per share, of the
Company.

      "Director" means each member of the Board on the Grant Date who is not an
employee of the Company or of a parent, subsidiary or affiliate of the Company.

      "Fair Market Value" means the closing price per share of the Common Stock
on the date immediately preceding the Grant Date.

      "Grant Date" means the Annual Grant Date or Initial Grant Date, whichever
is applicable.

      "Initial Grant Date" means May 24, 1996 or the date on which a Director is
first elected as a member of the Board, if the Director is not a member of the
Board on such date.

      "Option" means an option to purchase shares of Common Stock granted
pursuant to the Plan.

      "Plan" means the TETRA Technologies, Inc. Director Stock Option Plan as
set forth herein and as amended from time to time.

3. Common Stock Subject to the Plan

      The maximum aggregate number of shares of Common Stock with respect to
which Options shall be granted from time to time under the Plan is 100,000. The
Common Stock issued under the Plan may be either previously authorized but
unissued shares or treasury shares acquired by the Company. In the event that
all or part of any Option expires, lapses, is forfeited or otherwise terminates,
any shares of Common Stock allocable to the terminated portion of such Option
may again be made subject to an Option granted under the Plan.

4. Administration of the Plan

      The Plan shall be administered by the Board. The Board shall construe the
Plan, prescribe and rescind rules and regulations relating to the Plan and make
all other determinations deemed necessary or advisable for the administration of
the Plan, subject to the limitations of Section 11.

5. Automatic Grant of Options

      Subject to Section 7, each Director on his Initial Grant Date and on each
Annual Grant Date thereafter shall receive a grant of an Option to purchase
6,000 shares of Common Stock.

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6. Terms of Options

      Upon the grant of each Option, the Company and each Director shall enter
into an agreement specifying the purchase price and including or incorporating
by reference the substance of all of the following provisions and such other
provisions consistent with the Plan as the Board may determine.

            (a) The term of each Option shall be five years from its Grant Date,
      subject to its earlier termination in accordance with paragraph (f).

            (b) In no event shall an Option be exercisable prior to the first
      day that is six months after its Grant Date. Each Option shall be vested
      immediately on its Grant Date.

            (c) The purchase price of the shares of Common Stock subject to each
      Option shall be the Fair Market Value of the Common Stock on the Grant
      Date of the Option.

            (d) The purchase price of shares of Common Stock acquired pursuant
      to an Option shall be paid in full at the time the Option is exercised in
      cash or by delivery of shares of Common Stock or by a combination of cash
      and shares of Common Stock.

            (e) No Option shall be transferable otherwise than by will or the
      laws of descent and distribution, and an Option shall be exercisable
      during the Director's lifetime only by the Director. If a Director dies,
      the person or persons (including his estate) to whom his rights under any
      Option shall have passed by will or by laws of descent and distribution
      shall be entitled to exercise the Option for a period of one year after
      the death of the Director (but only to the extent exercisable by the
      Director at the time of his death).

            (f) If a Director's membership on the Board terminates for any
      reason other than death, an Option held at the date of termination may be
      exercised in whole or in part (but only to the extent exercisable by the
      Director at the time of such termination) at any time within 90 days after
      the date of such termination (but in no event after the term of the Option
      expires) and shall thereafter automatically terminate.

            (g) An Option may not be exercised for a fractional share. No Option
      may be exercised after the expiration of its term.

            (h) An Option shall be deemed to be exercised when (i) written
      notice of such exercise has been given to the Company in accordance with
      the terms of the agreement governing the Option by the person entitled to
      exercise the Option and (ii) full payment for the shares of Common Stock
      with respect to which the Option is exercised has been received by the
      Company. Until the issuance of the stock certificates (as evidenced by the
      appropriate entry on the books of the Company or of a duly authorized
      transfer agent of the Company), no right to vote or receive dividends or
      any other rights as a stockholder shall exist with respect to Option
      shares notwithstanding the exercise of the Option. No adjustment will be
      made for a dividend or other rights for which the record date is prior to
      the date the stock certificates are issued, except as provided in Section
      7.

7. Proration of Grant

      A Director who first becomes a member of the Board after May 24, 1996
shall receive, on the first Annual Grant Date following the date on which he
became a member of the Board, an Option to purchase the number of shares of
Common Stock equal to the product of 6,000 and a fraction, the numerator of
which is the number of days during the year preceding such Annual Grant Date
that such Director served as a member of the Board and the denominator of which
is 365.

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8. Anti-Dilution Adjustments

      In the event of a change in the capitalization of the Company due to a
stock split, stock dividend, recapitalization, merger, consolidation,
combination, or similar event, the aggregate number of shares of Common Stock
subject to the Plan, the terms of any outstanding Options and the number of
shares to be automatically granted on the Grant Dates under the terms of the
Plan shall be adjusted automatically to reflect such change.

9. Preemption by Applicable Laws and Regulations

      Anything in the Plan or any option agreement entered into pursuant to the
Plan to the contrary notwithstanding, if any law, regulation or requirement of
any governmental authority having jurisdiction over the Company shall require
either the Company or the Director (or his beneficiary) to take any action in
connection with any determination under the Plan or any issuance or other
distribution of shares or the making of payment of such shares, the issuance or
distribution of such shares or the making of such determination or payment, as
the case may be, shall be deferred until such action shall have been taken.

10. Effective Date and Duration of Plan

      The Plan was adopted by the Board of Directors of the Company on February
17, 1993 and amended effective May 24, 1996. The Plan became effective on
December 31, 1992. Subject to Section 11, the Plan shall continue indefinitely.

11. Termination and Amendment

      The Board may suspend, terminate, modify or amend the Plan; provided that
any amendment that would increase the aggregate number of shares of Common Stock
which may be issued under the Plan or materially modify the requirements as to
eligibility for participation in the Plan shall be subject to the approval of
the Company's stockholders; and provided further, that no amendment or
modification shall be made more than once every six months, other than to
comport with changes in the Internal Revenue Code of 1986 or regulations
promulgated thereunder. No suspension, termination, modification or amendment of
the Plan may terminate a Director's outstanding Options or materially adversely
affect a Director's rights under such Options.

12. Director's Agreement

      If, in the opinion of counsel for the Company, at the time of the exercise
of any Option it is necessary or desirable, in order to comply with any then
applicable laws or regulations relating to the sale of securities, for the
Director exercising the Option to agree to hold for investment any shares issued
to the Director without intention to resell or distribute the same and for the
Director to agree to dispose of such shares only in compliance with such laws
and regulations, the Director shall be required, upon the request of the
Company, to execute and deliver to the Company a further agreement to such
effect.

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                                                                   Exhibit 10.10

                            TETRA TECHNOLOGIES, INC.

                         1998 DIRECTOR STOCK OPTION PLAN

                             I. Purpose of the Plan

      The purpose of the TETRA Technologies, Inc. 1998 Director Stock Option
Plan (the "Plan") is to permit TETRA Technologies, Inc., a Delaware corporation
(the "Company"), to attract and retain qualified individuals to serve as
directors of the Company and to align the interests of such individuals more
closely with the interest of the Company's stockholders. Accordingly, the
Company may make awards ("Awards") to directors in the form of stock options
("Options") with respect to shares of the Company's common stock, par value
$0.01 per share ("Stock"). Options shall be nonqualified stock options, which
are not intended to qualify as incentive stock options under Section 422 of the
Internal Revenue Code of 1986, as amended (the "Code").

                               II. Administration

      The Plan shall be administered by the Board of Directors of the Company
(the "Board") or such committee of members of the Board as the Board may appoint
(the "Committee"). Committee members may resign at any time by delivering
written notice to the Board. Vacancies in the Committee, however caused, shall
be filled by the Board. The Committee is authorized to interpret the Plan and
may from time to time adopt such rules and regulations, not inconsistent with
the provisions of the Plan, as it may deem advisable to carry out the Plan. The
Committee shall act by a majority of its members in office and the Committee may
act either by vote at a telephonic or other meeting or by a memorandum or other
written instrument signed by all of the members of the Committee.

      The Committee shall have the sole authority to determine the terms and
provisions of the Option agreements (collectively, the "Agreements") entered
into in connection with Awards under the Plan; to prepare and distribute, in
such manner as the Committee determines to be appropriate, information about the
Plan; and to make all other determinations deemed necessary or advisable for the
administration of the Plan. The Committee may vary the terms and provisions of
the Agreements in its discretion.

      The day-to-day administration of the Plan may be carried out by such
officers and employees of the Company as shall be designated from time to time
by the Committee. Members of the Committee shall not receive compensation for
their services as members, but all expenses and liabilities they incur in
connection with the administration of the Plan shall be borne by the Company.
The Committee may employ attorneys, consultants, accountants, appraisers,
brokers or other persons, and the Committee, the Board, the Company and the
officers and employees of the Company shall be entitled to rely upon the advice,
opinions or valuations of any such persons. The interpretation and construction
by the Committee of any provisions of the Plan or of any Award under the Plan
and any determination by the Committee under any provision of the Plan or any
such Award shall be final and conclusive for all purposes. Neither the Committee
nor any member thereof shall be liable for any act, omission, interpretation,
construction or determination made in connection with the Plan in good faith,
and the members of the Committee shall be entitled to indemnification and
reimbursement by the Company in respect of any claim, loss, damage or expense
(including counsel fees) arising therefrom to the full extent permitted by law.
The members of the Committee shall be named as insureds under any directors and
officers liability insurance coverage that may be in effect from time to time.

      The Committee shall have authority to grant Options, to determine the
purchase price of the Stock covered by each Option (the "Exercise Price"), the
term of each Option, the directors to whom, and the times at which, Options
shall be granted, and the number of shares to be covered by each Option. All
decisions made by the Committee in selecting the persons to whom Awards shall be
granted, in establishing the number of shares covered by each Award and the
other terms and provisions thereof, and in construing the provisions of the Plan
and the Agreements shall be final.

      Only directors of the Company shall be eligible to receive Awards under
the Plan. In no event shall any director or his legal representatives, heirs,
legatees, distributees, or successors have any right to participate in the Plan,
except to such extent, if any, as the Committee shall determine.

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                         III. Shares Subject to the Plan

      The aggregate number of shares which may be issued under Awards granted
under the Plan shall not exceed 75,000 shares of Stock of the Company. Such
shares shall consist of previously issued shares reacquired by the Company.
Until termination of the Plan and the expiration of all Awards granted under the
Plan, the Company shall at all times make available a sufficient number of
shares to meet the requirements of the Plan and the outstanding Awards. The
aggregate number of shares which may be issued under Awards granted under the
Plan shall be subject to adjustment as provided in Article V hereof.

                              IV. Grants of Options

            A. Options. Options granted under the Plan shall be for such number
      of shares of Stock and subject to such terms and conditions. The Committee
      may grant Options at any time and from time to time through, but not after
      December 14, 2008 to any optionee eligible to receive the same.

            B. Terms of Options. Options granted pursuant to this Plan shall be
      evidenced by Agreements that shall comply with and be subject to the
      following terms and conditions and may contain such other provisions,
      consistent with this Plan, as the Committee shall deem advisable.
      References herein to an Agreement shall include, to the extent applicable,
      any amendments to such Agreement.

                  1. Payment of Option Exercise Price. Upon exercise of an
            Option, the full Exercise Price for the shares with respect to which
            the Option is being exercised shall be payable to the Company (i) in
            cash or by check payable and acceptable to the Company, (ii) subject
            to the approval of the Committee, by tendering to the Company shares
            of Stock owned by the optionee having an aggregate Market Value Per
            Share as of the date of exercise and tender that is not greater than
            the full Exercise Price for the shares with respect to which the
            Option is being exercised and by paying any remaining amount of the
            Exercise Price as provided in (i) above, or (iii) subject to such
            instructions as the Committee may specify, at the optionee's written
            request the Company may deliver certificates for the shares of Stock
            for which the Option is being exercised to a broker for sale on
            behalf of the optionee, provided that the optionee has irrevocably
            instructed such broker to remit directly to the Company on the
            optionee's behalf the full amount of the Exercise Price and any
            required tax withholdings from the proceeds of such sale. In the
            event that the optionee elects to make payment as allowed under
            clause (ii) above, the Committee may, upon confirming that the
            optionee owns the number of additional shares being tendered,
            authorize the issuance of a new certificate for the number of shares
            being acquired pursuant to the exercise of the Option less the
            number of shares being tendered upon the exercise and return to the
            optionee (or not require surrender of) the certificate for the
            shares being tendered upon the exercise. Payment instruments will be
            received subject to collection.

                  2. Number of Shares. Each Agreement shall state the total
            number of shares of Stock that are subject to the Option.

                  3. Exercise Price. The Exercise Price for each Option shall be
            fixed by the Committee at the Grant Date.

                  4. Market Value Per Share. The "Market Value Per Share" as of
            any particular date shall be determined by any fair and reasonable
            means determined by the Committee, which may include, if the Stock
            is listed for trading on a national or regional stock exchange, the
            closing price quoted on such exchange which is published in The Wall
            Street Journal reports for the day of the grant, or if no trade of
            the Stock shall have been reported for such date, the closing price
            quoted on such exchange which is published in The Wall Street
            Journal reports for the next day prior thereto on which a trade of
            the Stock was so reported, or if the shares are not so listed or
            admitted to trading, the average of the highest reported bid and
            lowest reported asked prices as furnished by the National
            Association of Securities Dealers, Inc., through NASDAQ, or through
            a similar organization if NASDAQ is no longer reporting such
            information. If shares of the Stock are not listed or admitted

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            to trading on any exchange or quoted through NASDAQ or any similar
            organization, the "Market Value Per Share" shall be determined by
            the Committee in good faith using any fair and reasonable means
            selected in its discretion.

                  5. Term. The term of each Option shall be determined by the
            Committee at the Grant Date; provided, however, that each Option
            shall, notwithstanding anything in the Plan or an Agreement to the
            contrary, expire not more than ten years from the Grant Date or, if
            earlier, the date specified in the Agreement.

                  6. Date of Exercise. In the discretion of the Committee, each
            Agreement may contain a provision not inconsistent with Article V.E.
            stating that the Option granted therein may not be exercised in
            whole or in part for a period or periods of time specified in such
            Agreement, subject to Article V.E., and except as so specified
            therein, any Option may be exercised in whole at any time or in part
            from time to time during its term. The Committee may, however, at
            any time, in its sole discretion amend any outstanding Option to
            accelerate the time that such Option shall be exercisable or to
            provide that the time for exercising such Option shall be
            accelerated upon the occurrence of a specified event.

                  7. Termination of Directorship. In the event that an
            optionee's term as a director of the Company shall terminate, the
            optionee's Options shall be exercisable by him as set forth in the
            Agreement governing such Options.

                      V. Recapitalization or Reorganization

            A. The existence of the Plan and the Awards granted hereunder shall
      not affect in any way the right or power of the Board or the stockholders
      of the Company to make or authorize any adjustment, recapitalization,
      reorganization or other change in the Company's capital structure or its
      business, any merger or consolidation of the Company, any issue of bonds,
      debentures, preferred or prior preference stocks ahead of or affecting
      Stock, the dissolution or liquidation of the Company or any sale or
      transfer of all or any part of its assets or business, or any other
      corporate act or proceeding.

            B. The shares with respect to which Awards may be granted are shares
      of Stock as presently constituted, but if, and whenever, prior to the
      termination of the Plan or the expiration of an Award theretofore granted,
      the Company shall effect a subdivision or consolidation of shares of Stock
      or the payment of a stock dividend on Stock without receipt of
      consideration by the Company, the remaining shares of Stock available
      under the Plan and the number of shares of Stock with respect to which
      such Award may thereafter be exercised (i) in the event of an increase in
      the number of outstanding shares, shall be proportionately increased and
      the Exercise Price per share shall be proportionately reduced, and (ii) in
      the event of a reduction in the number of outstanding shares, shall be
      proportionately reduced, and the Exercise Price per share shall be
      proportionately increased.

            C. Except as may otherwise be expressly provided in the Plan, the
      issuance by the Company of shares of stock of any class or securities
      convertible into shares of stock of any class, for cash, property, labor
      or services, upon direct sale, upon the exercise of rights or warrants to
      subscribe therefor, or upon conversion of shares or obligations of the
      Company convertible into such shares or other securities, and in any case
      whether or not for fair value, shall not affect, and no adjustment by
      reason thereof shall be made with respect to, the number of shares of
      Stock available under the Plan or subject to Awards theretofore granted or
      the Exercise Price per share of outstanding Awards.

            D. If the Company effects a recapitalization or otherwise materially
      changes its capital structure (both of the foregoing are herein referred
      to as a "Fundamental Change"), then thereafter upon any exercise of an
      Option theretofore granted the optionee shall be entitled to purchase
      under such Option, in lieu of the number of shares of Stock as to which
      such Option shall then be exercisable, the number and class of shares of
      stock and securities to which the optionee would have been entitled
      pursuant to the terms of the

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      Fundamental Change if, immediately prior to such Fundamental Change, the
      optionee had been the holder of record of the number of shares of Stock as
      to which such Option is then exercisable.

            E. Notwithstanding any other provision of this Plan to the contrary,
      in the event of a Corporate Change, all outstanding Awards automatically
      shall become fully vested immediately prior to such Corporate Change (or
      such earlier time as set by the Committee), all restrictions, if any, with
      respect to such Awards shall lapse, all performance criteria, if any, with
      respect to such Awards shall be deemed to have been met in full, and
      unless the Company survives as an independent publicly traded company, all
      Options outstanding at the time of the event or transaction shall
      terminate, except to the extent provision is made in writing in connection
      with such event or transaction for the continuation of the Plan and/or the
      assumption of the Options theretofore granted, or for the substitution for
      such Options of new options covering the stock of a successor entity, or
      the parent or subsidiary thereof, with appropriate adjustments as to the
      number and kinds of shares and exercise prices, in which event the Plan
      and Options theretofore granted shall continue in the manner and under the
      terms so provided. A "Corporate Change" shall have occurred if:

                  (i) the Company shall not be the surviving entity in any
            merger or consolidation (or survives only as a subsidiary of another
            entity),

                  (ii) the Company sells, exchanges, disposes or otherwise
            transfers all or substantially all of its assets to any other person
            or entity (other than a wholly-owned subsidiary),

                  (iii) any person or entity (including a "group" as
            contemplated by Section 13(d)(3) of the 1934 Act) after the date
            hereof acquires or gains ownership or control of (including, without
            limitation, power to vote) more than 50% of the outstanding shares
            of Stock,

                  (iv) the Company is to be dissolved and liquidated, or

                  (v) as a result of or in connection with a contested election
            of directors, the persons who were directors of the Company before
            such election shall cease to constitute a majority of the Board.

            For purposes of the Corporate Changes described in (iii) and (v)
      above, the "Committee" shall be either the Committee as constituted prior
      to the occurrence of such Corporate Change or, if no Committee had been
      appointed, the Board as constituted prior to the occurrence of such
      Corporate Change.

            Notwithstanding the foregoing, with the consent of the optionee, the
      Committee may in lieu of the foregoing make such provision with respect to
      any Corporate Change as it deems appropriate.

                            VI. Optionee's Agreement

      If, at the time of the exercise of any Award, in the opinion of counsel
for the Company, it is necessary or desirable, in order to comply with any then
applicable laws or regulations relating to the sale of securities, for the
optionee exercising the Award to agree to hold any shares issued to the optionee
for investment and without intention to resell or distribute the same and for
the optionee to agree to dispose of such shares only in compliance with such
laws and regulations, the optionee will, upon the request of the Company,
execute and deliver to the Company a further agreement to such effect.

                  VII. Termination of Authority to Grant Awards

      No Awards will be made pursuant to this Plan after December 14, 2008.

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                         VIII. Amendment and Termination

      The Board may from time to time and at any time alter, amend, suspend,
discontinue or terminate this Plan and any Awards hereunder; provided, that no
change in any Award theretofore granted may be made which would impair the
rights of the optionee, without the consent of such optionee.

                IX. Preemption by Applicable Laws and Regulations

      Anything in the Plan or any Agreement entered into pursuant to the Plan to
the contrary notwithstanding, if, at any time specified herein or therein for
the making of any determination, the issuance or other distribution of shares of
Stock, any law, regulation or requirement of any governmental authority having
jurisdiction in the premises shall require either Company or the employee or
consultant (or the employee's or consultant's beneficiary), as the case may be,
to take any action in connection with any such determination, the shares then to
be issued or distributed, or such payment, the issue or distribution of such
shares or the making of such determination or payment, as the case may be, shall
be deferred until such action shall have been taken.

                                X. Miscellaneous

            A. No Rights as a Stockholder. An optionee shall have no rights as a
      stockholder with respect to shares covered by such optionee's Award until
      the date of the issuance of shares to the optionee pursuant thereto. No
      adjustment will be made for dividends or other distributions or rights for
      which the record date is prior to the date of such issuance.

            B. No Right to Corporate Assets. Nothing contained in the Plan shall
      be construed as giving any optionee, such optionee's beneficiaries or any
      other person any equity or other interest of any kind in any assets of the
      Company or creating a trust of any kind or a fiduciary relationship of any
      kind between the Company and any such person.

            C. No Restriction on Corporate Action. Nothing contained in the Plan
      shall be construed to prevent the Company from taking any corporate action
      that is deemed by the Company to be appropriate or in its best interest,
      whether or not such action would have an adverse effect on the Plan or any
      Award made under the Plan. No optionee, beneficiary or other person shall
      have any claim against the Company as a result of any such action.

            D. Non-assignability. Neither an optionee nor an optionee's
      beneficiary shall have the power or right to sell, exchange, pledge,
      transfer, assign or otherwise encumber or dispose of such optionee's or
      beneficiary's interest arising under the Plan or any Award received under
      the Plan; nor shall such interest be subject to seizure for the payment of
      an optionee's or beneficiary's debts, judgments, alimony, or separate
      maintenance or be transferable by operation of law in the event of an
      optionee's or beneficiary's bankruptcy or insolvency and to the extent any
      such interest arising under the Plan or an Award received under the Plan
      is awarded to a spouse pursuant to any divorce proceeding, such interest
      shall be deemed to be terminated and forfeited notwithstanding any vesting
      provisions or other terms herein or in the agreement evidencing such
      Award.

            E. Application of Funds. The proceeds received by the Company from
      the sale of shares pursuant to the Plan will be used for general purposes.

            F. Governing Law; Construction. All rights and obligations under the
      Plan shall be governed by, and the Plan shall be construed in accordance
      with, the laws of the State of Delaware without regard to the principles
      of conflicts of laws. Titles and headings to Sections herein are for
      purposes of reference only, and shall in no way limit, define or otherwise
      affect the meaning or interpretation of any provisions of the Plan.

      Adopted effective as of December 14, 1998.

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