EXHIBIT 3.16

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                       LIMITED LIABILITY COMPANY AGREEMENT

                                       OF

                           ONES Equatorial Guinea LLC

                      a Delaware limited liability company

                           Dated as of August 5, 2002

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                       LIMITED LIABILITY COMPANY AGREEMENT
                                       OF
                           ONES EQUATORIAL GUINEA LLC

     This Limited Liability Company Agreement, dated as of August 5, 2002 (this
"Agreement"), is made and entered into by and among Ondeo Nalco Energy Services,
L.P., a Delaware limited partnership ("ONES LP"), and such other Persons as
maybe admitted from time to time as Members of the Company in accordance with
the terms of this Agreement and the Act.

     SECTION 1. Formation of Limited Liability Company. ONES Equatorial Guinea
LLC (the "Company") was previously formed as a limited liability company
pursuant to Section 18-201 of the Act by the filing by Michael P. Murphy, an
"authorized person" within the meaning of the Act, of the Certificate of
Formation of the Company (as amended from time to time, the "Certificate of
Formation") with the Secretary of State on August 5, 2002. The Members hereby
adopt, confirm and ratify said Certificate of Formation and all acts taken by
Michael P. Murphy in connection therewith. This Agreement, in accordance with
Section 18-201(d) of the Act, shall be effective as of August 5, 2002 (the
"Effective Date"). The rights and duties of the Members shall be as provided in
the Act, except as modified by the Company's Certificate of Formation and this
Agreement. For and in consideration of the foregoing and the mutual covenants
herein contained and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the undersigned hereby agree to
the terms and conditions of this Agreement. In the event of any conflict between
the Company's Certificate of Formation and this Agreement, then to the extent
permitted by law, this Agreement shall control. To the extent any provision of
this Agreement is prohibited or ineffective under the Act, this Agreement shall
be considered amended to the smallest degree possible in order to make this
Agreement effective under the Act. In the event the Act is subsequently amended
or interpreted in such a way to make any provision of this Agreement that was
formerly invalid valid, such provision shall be considered to be valid from the
effective date of such interpretation or amendment.

     SECTION 2. Name. The name of the Company shall be "ONES Equatorial Guinea
LLC". The business of the Company may be conducted, upon compliance with all
applicable laws, under any name designated by the Managers.

     SECTION 3. Definitions.

     For purposes of this Agreement, unless the context clearly indicates
otherwise, the following terms shall have the following meanings:



     "Act" means the Delaware Limited Liability Company Act, Delaware Code Title
6, Sections 18-101 et seq., as amended from time to time.

     "Agreement" means this Limited Liability Company Agreement, as amended,
modified or supplemented from time to time.

     "Capital Account" means the account established on the books and records of
the Company for each Member. Each Member's Capital Account shall initially equal
the value of the Capital Contribution to the Company made by the Member. During
the term of the Company, each Member's Capital Account shall be (i) increased by
the amount of (w) income and gain allocated to the Member and (x) any cash or
property subsequently contributed by the Member to the Company, and (ii)
decreased by the amount of (y) loss and deduction allocated to the Member and
(z) all cash and property distributed to the Member, and shall otherwise be kept
in accordance with applicable United States Treasury Regulations promulgated
under Section 704(b) of the Code. During such time that the Company is owned by
only one Member, the definition of "Capital Account" shall be inapplicable.

     "Capital Contribution" means the total amount of cash or other property
contributed to the Company by a Member. Contributed property shall be valued at
the amount, net of any liabilities assumed to which the contributed property is
subject, set forth in Schedule I attached hereto, as amended, modified or
supplemented from time to time.

     "Code" means the United States Internal Revenue Code of 1986, as amended,
modified or rescinded from time to time, or any similar provision of succeeding
law.

     "Company" has the meaning set forth in Section 2.

     "Effective Date" has the meaning set forth in Section 1.

     "IRS" means the United States Internal Revenue Service or any successor
entity.

     "Majority Interest" means one or more Members who in the aggregate hold
more than 50% of all Membership Units.

     "Manager" or "Managers" means one or more individuals who are elected from
time to time by the Members as a manager of the Company in accordance with the
terms of this Agreement.

     "Member" means any Person who holds Membership Units and whose name is set
forth on Schedule I attached hereto, as amended, modified or supplemented from
time to time.

     "Membership Units" means the limited liability company interests in the
Company held by the Members, expressed as a number of units held by each Member
and set forth opposite such Member's name on Schedule I attached hereto, as
amended, modified or supplemented from time to time.

     "ONES LP" has the meaning set forth in the preamble.



     "Net Cash Flow" means for any period the amount, computed on a cash basis,
equal to:

          (i) the sum of (A) gross receipts from business operations, all
     investment income and investment gain of the Company and all other cash
     received by the Company, all without double counting, and (B) any amounts
     released from Reserves;

     decreased by

          (ii) the sum of (A) disbursements of the Company for operating
     expenses, expenditures for capital investments and reinvestments, principal
     payments on indebtedness, interest and other expenses, including any
     repayment of indebtedness required or elected to be made in connection with
     any refinancing, sale or other event, and (B) any increase in Reserves.

     "Person" means any individual, corporation, partnership, association,
limited liability company, trust, estate or other enterprise or entity.

     "Reserves" means the reasonable reserves established and maintained from
time to time in amounts reasonably determined by the Managers to be adequate and
sufficient for costs, expenses and other amounts payable in the Company's
business or otherwise for the long-term goals of the Company or any other
purpose, including reserves for unforeseen or contingent liabilities, debts or
obligations.

     "Secretary of State" means the Secretary of State of the State of Delaware.

     "Tax Matters Member" has the meaning set forth in Section 23(c).

     "Treasury Regulations" means the income tax regulations, including any
temporary regulations, from time to time promulgated under the Code.

     SECTION 4. Business of the Company. The purpose of the Company is to carry
on any lawful business purpose or activity for which limited liability companies
may be formed in accordance with Section 18-106 of the Act.

     SECTION 5. Term. The term of the Company as a limited liability company
began on the Effective Date and shall continue until the Company is dissolved in
accordance with this Agreement, the Act or other applicable law.

     SECTION 6. Principal Place of Business. The principal place of business of
the Company shall be located at Ondeo Nalco Center, Naperville, Illinois 60563.
The Managers may, from time to time, change the principal place of business of
the Company and/or establish additional places of business of the Company.



     SECTION 7. Registered Agent; Registered Office. The registered agent for
service of process on the Company in the State of Delaware shall be The
Corporation Trust Company. The registered office of the Company in the State of
Delaware shall be c/o The Corporation Trust Company, 1209 Orange Street,
Wilmington, Delaware 19805, in the County of New Castle. The Managers may, from
time to time, change the registered agent or office through appropriate filings
with the Secretary of State.

     SECTION 8. Capital Contributions; Membership Units.

     (a) Membership Units. Each Member shall receive the number of Membership
Units set forth opposite such Member's name on Schedule I attached hereto.

     (b) Additional Contributions; Interest. No Member shall be obligated to
make any additional Capital Contribution. No Member shall be permitted to make
any additional Capital Contribution without the consent of the Managers and the
Majority Interest. Upon any additional Capital Contribution made by any Member,
the number of Membership Units held by such Member shall be adjusted in the
manner determined by the Managers and the Majority Interest and shall be set
forth on an amendment to Schedule I attached hereto. No Member has any
obligation to restore a deficit balance in such Member's Capital Account, if
any, or in the Company's balance sheet, or to make any contributions to the
Company in order to restore such deficit balance. No Member shall be paid
interest on any Capital Contribution.

     (c) Liability for Promised Contributions. A Member is obligated for
promises to make Capital Contributions, even if the Member is unable to perform
because of death, disability, or any other reason. If a Member does not make the
Member's required contribution of property, the Member is obligated, at the
option of the Company, to contribute cash equal to the value of the required
contribution.

     (d) Certificates for Membership Units. The Company shall, on request,
deliver to each Member a certificate indicating that such Member owns the number
of Membership Units set out thereon. Every certificate must be signed by a
Manager of the Company. If any certificate is lost, mutilated, stolen or
destroyed, the Company shall issue a replacement certificate to the Member upon
receipt of evidence satisfactory to the Managers of such loss, mutilation, theft
or destruction, and upon receiving such indemnification as the Managers deem
appropriate in the circumstances. In the event of a transfer pursuant to Section
18, the transferring Member shall return to the Company any certificate(s)
representing the Membership Units being transferred, and the Company shall, on
request, issue a new certificate to the transferee Member for any transferred
Membership Units. In the case of a transfer of less than all of the Membership
Units represented by a certificate, the Company shall, on request, issue to the
transferring Member a new certificate for the balance of the Membership Units
retained by the transferring Member.

     (e) Withdrawal and Resignation; Return of Capital Contribution. No Member
shall be entitled, except as provided in Section 18, to withdraw or resign as a
Member or, except as



provided in Section 20, to receive any part of such Member's Capital
Contribution or any distribution from the Company in connection therewith.

     (f) Membership Units are Securities. The Members agree (in accordance with
Section 8-103(c) of the Uniform Commercial Code as in effect in the States of
Delaware and Illinois) that the Membership Units shall constitute "securities"
as defined in and governed by Article 8 of the Uniform Commercial Code as in
effect in the States of Delaware and Illinois.

     SECTION 9. Distributions. Net Cash Flow shall be distributed among the
Members pro rata in accordance with their respective Membership Units from time
to time as determined by the Managers. In the event the Company is subject to
any tax or other obligation which is attributable to the interest of one or more
Members in the Company, but fewer than all the Members, such tax or other
obligation shall be specially allocated to, and charged against the Capital
Account of, such Member or Members, and the amounts otherwise distributable to
such Member or Members pursuant to this Agreement shall be reduced by such
amount.

     SECTION 10. Allocation of Income and Losses.

     (a) Allocations. For purposes of maintaining the books of the Company, all
items of income, gain, loss and deduction of the Company shall be allocated to
the Members in accordance with their respective Membership Units. For United
States federal and (where permitted) state income tax purposes, (i) during such
time that the Company is owned by only one Member, ONES LP (and any subsequent
sole Member) shall take into account all income, gains, losses, deductions and
credits of the Company directly on its tax return as if the Company were a
division of the sole Member and (ii) during such time that the Company is owned
by more than one Member, (A) except as provided in clause (C) hereof, all items
of income, gain, loss and deduction of the Company shall be allocated in the
same manner as each such item's correlative book item is allocated; (B) all tax
credits shall be allocated in the same manner as the receipt, income,
expenditure or deduction giving rise thereto is allocated; and (C)
notwithstanding clause (A) hereof, the allocations, if any, required by Section
704(c) of the Code and Sections 1.704-1(b)(2)(iv)(d)(3) and 1.704-1(b)(2)(iv)(f)
of the Treasury Regulations shall be effected.

     (b) Change in Membership Units. If there is a change in the number of
Membership Units held by any Member during any year, allocations among the
Members shall be made pro rata in accordance with the number of Membership Units
held by each Member from time to time during such year in accordance with
Section 706 of the Code using the closing-of-the-books method, except that
depreciation, amortization and similar items shall be deemed to accrue ratably
on a daily basis over the entire year if the corresponding asset is owned by the
Company for the entire year, and over the portion of a year after such asset is
acquired by the Company if such asset is acquired during the year.

     SECTION 11. Withholding. The Company is authorized to withhold from
distributions to be made to a Member, or with respect to allocations to a
Member, and to pay over to a federal, state or local government, any amounts
required to be withheld pursuant to the Code or any provisions of any other
federal, state or local law. Any amounts so withheld shall



be treated as distributed to such Member for all purposes of this Agreement and
shall be offset against the net amounts otherwise distributable to such Member.
The Company may also withhold from distributions that would otherwise be made to
a Member, and apply to the obligations of such Member, any amounts that such
Member owes to the Company. In addition, any tax imposed upon the Company
resulting from any Member's ownership of Membership Units shall be treated as a
distribution to such Member and shall reduce future distributions to such
Member.

     SECTION 12. Books, Records and Accounting.

     (a) Books and Records. The Company shall maintain complete and accurate
books and records of the Company's business and affairs in accordance with
generally accepted accounting principles, consistently applied. The books and
records shall be maintained at the principal place of business of the Company
and shall be accessible to the Members in accordance with the Act.

     (b) Fiscal Year; Accounting. The Company's fiscal year shall be the
calendar year, provided that the Managers may fix by resolution another period
to be the Company's fiscal year. The accounting methods and principles to be
followed by the Company shall be selected from time to time by the Managers.

     (c) Reports. During such time that the Company is owned by more than one
Member, upon any such Member's request the Company shall provide to the Members
reports concerning the financial condition and results of operation of the
Company and the changes in Members' Capital Accounts, if any, within ninety (90)
days after the end of each fiscal year.

     SECTION 13. Company Funds. The funds of the Company shall be deposited in
such bank or other financial institution account or accounts, or invested in
such interest-bearing or non-interest-bearing investments, as shall be
designated by the Managers. All withdrawals from any such accounts shall be made
only by the Managers or by individuals duly appointed by the Managers.

     SECTION 14. Managers.

     (a) Managers. The business and affairs of the Company shall be managed and
controlled by or under the direction of one or more Managers, which may exercise
all such powers of the Company and do all such lawful acts and things as are not
by law or by this Agreement directed or required to be exercised or done by the
Members. Unless otherwise set forth herein, each individual Manager, in his or
her capacity as such, shall have the authority to act on behalf of or bind the
Company.

     (b) Number, Qualification and Tenure. There shall be not less than one (1)
Manager and not more than ten (10) Managers. Within the limit above specified,
the number of Managers shall be determined from time to time by resolution of
the Members. The number of Managers shall be initially fixed at one. The initial
Manager shall be David J. Blair. The Managers shall



be elected by the Members, except as provided in paragraph (c) of this Section
14, and each Manager elected shall hold office until his or her successor is
elected and qualified or until his or her earlier death, resignation or removal.
Managers need not be Members.

     (c) Vacancies. Vacancies and newly created Manager positions resulting from
any increase in the number of Managers may be filled by a majority of the
Managers then in office, although less than a quorum, or by a sole remaining
Manager or by the Majority Interest; and each Manager so chosen shall hold
office until his or her successor is elected and qualified or until his or her
earlier death, resignation or removal. If there are no Managers in office, then
an election of Managers by the Members may be held.

     (d) Resignation. A Manager may resign at any time by giving written notice
to the Members and the other Managers. No formal action shall be required by the
Managers or the Members to make any such resignation effective.

     (e) Removal. A Manager may be removed with or without cause at any time by
a resolution adopted by the Majority Interest.

     (f) Compensation. The Majority Interest shall have the authority to fix the
compensation of Managers, which compensation may include reimbursement of the
expenses, if any, of attendance at meetings of the Managers or of a committee.

     SECTION 15. Meetings of Members.

     (a) Time and Place of Meetings. All meetings of the Members for the
election of Managers or for any other purpose shall be held at such time and
place, within or without the State of Delaware, as shall be designated by the
Managers. In the absence of any such designation by the Managers, each such
meeting shall be held at the principal office of the Company.

     (b) Annual Meetings. An annual meeting of the Members may be held for the
purpose of electing Managers and transacting such other business as may be
properly brought before the meeting. The date of the annual meeting shall be
determined by the Managers.

     (c) Special Meetings. Special meetings of the Members, for any purpose or
purposes, unless otherwise prescribed by law, may be called by the Managers, or
at the request in writing of the Majority Interest.

     (d) Notice of Meetings. Written notice of each meeting of the Members
stating the place, date and time of the meeting shall be given, not less than
ten nor more than sixty days before the date of the meeting, to each Member.

     (e) Quorum. The Majority Interest, present in person or represented by
proxy, shall constitute a quorum for the transaction of business at all meetings
of the Members, except as



otherwise required by law. If a quorum is not present or represented, the
Members present in person or represented by proxy at the meeting shall have
power, by the affirmative vote of the holders of a majority of the Membership
Units held by such Members, to adjourn the meeting to another time and/or place,
without notice other than announcement at the meeting, until a quorum shall be
present or represented. At such adjourned meeting, at which a quorum shall be
present or represented, any business may be transacted which might have been
transacted at the original meeting. If the adjournment is for more than thirty
days, or if after the adjournment a new record date is fixed for the adjourned
meeting, a notice of the adjourned meeting shall be given to each Member.

     (f) Voting. At all meetings of the Members, each Member shall be entitled
to cast one vote, in person or by proxy, for each Membership Unit held by such
Member on the record date for the meeting. When a quorum is present or
represented at any meeting, the vote of the holders of a majority of the
Membership Units present in person or represented by proxy shall decide any
question brought before such meeting, unless the question is one upon which, by
express provision of law or this Agreement, a different vote is required, in
which case such express provision shall govern and control the decision of such
question.

     (g) Informal Action by Members. Any action required to be taken at a
meeting of the Members, or any other action which may be taken at a meeting of
the Members, may be taken without a meeting, without prior notice and without a
vote, if a consent in writing, setting forth the action so taken, shall be
signed by the holders of Membership Units having not less than the minimum
number of votes that would be necessary to authorize or take such action at a
meeting at which all Membership Units entitled to vote thereon were present and
voted.

     (h) Actions Requiring Member Approval. Notwithstanding any other provision
of this Agreement, the affirmative vote or written consent of the Majority
Interest shall be required to approve the following matters:

          (i) The dissolution or winding up of the Company;

          (ii) The merger or consolidation of the Company;

          (iii) The sale, exchange, transfer, contribution, mortgage, pledge,
     encumbrance, lease or other disposition or transfer of all or substantially
     all of the assets of the Company;

          (iv) The election of Managers; and

          (v) Amendments to this Agreement; provided, however, that the Managers
     are expressly authorized to make such amendments to Schedule I attached
     hereto as they deem necessary to reflect any admission of a new Member or
     any assignment or issuance of Membership Units which has been approved in
     accordance with Section 18 or any additional capital contribution by a
     Member which has been approved in accordance with Section 8(b).



     SECTION 16. Officers; Agents. Managers shall have the power to appoint any
person or persons as agents (who maybe referred to as officers) and to hire
employees or other agents to act for the Company with such titles, if any, as
the Managers deem appropriate and to delegate to such officers, employees or
agents such of the powers as are granted to the Managers hereunder. The
officers, employees or agents so appointed may have such titles as the Managers
shall deem appropriate, which may include (but need not be limited to) Chairman,
President, Chief Executive Officer, Executive Vice President, Vice President,
Chief Operating Officer, Chief Financial Officer, Treasurer, Assistant
Treasurer, Controller, Secretary or Assistant Secretary. Unless the authority of
the agent designated as the officer in question is limited by the Manager
appointing him, any officer so appointed shall have the same authority to act
for the Company as a corresponding officer of a Delaware corporation would have
to act for a Delaware corporation in the absence of a specific delegation of
authority. Managers, in their sole discretion, may ratify any act previously
taken by an officer, employee or agent acting on behalf of the Company, such
ratification to be effected by vote, resolution or otherwise, provided that such
vote, resolution or other action would have been sufficient hereunder to
authorize the taking of such act by such officer or agent. The Managers may from
time to time determine the compensation of any employees, agents and officers of
the Company or may delegate some or all compensation decisions to officers or
employees of the Company.

     SECTION 17. Limitation of Liability, Indemnification and Exculpation.

     (a) Limitation of Liability. The debts, obligations and liabilities of the
Company, whether arising in contract, tort or otherwise, shall be solely the
debts, obligations and liabilities of the Company, and no Member, Manager or
officer of the Company shall be obligated personally for any such debt,
obligation or liability of the Company solely by reason of being a Member,
Manager or officer of the Company, as applicable.

     (b) Exculpation. To the fullest extent now or hereafter permitted by law,
Managers and officers of the Company shall have no personal liability to the
Company or its Members for monetary damages for breach of fiduciary duty as
Manager or officer of the Company, as applicable.

     (c) Indemnification. The Company shall indemnify, in accordance with and to
the full extent now or hereafter permitted by law, any Person who was or is a
party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative (including, without limitation, an action by or in the right of
the Company) by reason of the fact that such Person is or was acting as a
Manager or officer of the Company and may so indemnify a Person who was or is a
party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative (including, without limitation, by or in the right of the
Company), reason of the fact that such Person is or was an employee or agent of
the Company, or is or was serving at the request of the Company in any other
capacity for or on behalf of the Company, against expenses (including attorneys'
fees), judgements, fines and amounts paid in settlement actually and reasonably
incurred by such Person in connection therewith. The termination of any action,
suit or proceeding by judgment, order, settlement, conviction, or upon a plea of
nolo contendere or its equivalent, shall not, of itself, create a



presumption (a) that the Person did not act in good faith and in a manner which
he or she reasonably believed to be in or not opposed to the best interests of
the Company, or (b) with respect to any criminal action or proceeding, that the
Person had reasonable cause to believe that his or her conduct was unlawful. The
right to indemnification conferred by this Section 3(c) shall be deemed to be a
contract between the Company and each person referred to herein.

     (d) Advancement of Expenses. Expenses (including, without limitation,
attorneys' fees and expenses) incurred by a Member, Manager or officer of the
Company in defending a civil, criminal, administrative or investigative action,
suit or proceeding shall be paid by the Company in advance of the final
disposition of such action, suit or proceeding upon receipt of an undertaking by
or on behalf of the Member, Manager or officer to repay such amount if it shall
ultimately be determined that such Member, Manager or officer is not entitled to
be indemnified by the Company under this Section 17 or under any other contract
or agreement between such Member, Manager or officer and the Company. Such
expenses (including attorneys' fees) incurred by employees or agents of the
Company or by Persons serving at the request of the Company as a director,
trustee, employee, member, manager or agent of another limited liability
company, corporation, partnership, joint venture, trust or other enterprise may
be so paid upon the receipt of the aforesaid undertaking and such other terms
and conditions, if any, as the Managers deem appropriate.

     (e) Rights Not Exclusive. The indemnification and advancement of expenses
provided by this Section 17 shall not be deemed exclusive of any other rights to
which those seeking indemnification or advancement of expenses may be entitled
under any agreement, vote of Members or otherwise, both as to action in such
Person's official capacity and as to action in another capacity while holding
such office.

     (f) Insurance. The Company may purchase and maintain insurance on behalf of
any Person who is or was a Member, Manager, officer, employee or agent of the
Company, or is or was serving at the request of the Company as a director,
trustee, member, manager, officer, employee or agent of another limited
liability company, corporation, partnership, joint venture, trust or other
enterprise against any liability asserted against such Person and incurred by
such Person in any such capacity, or arising out of such Person's status as
such, whether or not such Person would be entitled to indemnity against such
liability under the provisions of this Section 17.

     (g) Successors. The indemnification and advancement of expenses provided
by, or granted pursuant to, this Section 17 shall continue as to a Person who
has ceased to be a director, trustee, member, manager, officer, employee or
agent and shall inure to the benefit of the successors, heirs, executors and
administrators of such a Person.

     (h) Certain References. For purposes of this Section 17, references to "the
Company" shall include, in addition to the resulting business entity, any
constituent business entity (including any constituent of a constituent)
absorbed in a consolidation or merger which, if its separate existence had
continued, would have had power and authority to indemnify its directors,
trustees, members, managers, officers, employees or agents, so that any person
who is or was a



director, trustee, member, manager, officer, employee or agent of such
constituent business entity, or is or was serving at the request of such
constituent business entity as a director, trustee, member, manager, officer,
employee or agent of another limited liability company, corporation,
partnership, joint venture, trust or other enterprise, shall stand in the same
position under the provisions of this Section 17 with respect to the resulting
or surviving business entity as he would have with respect to such constituent
business entity if its separate existence had continued. In addition, for
purposes of this Section 17, references to "other enterprises" shall include
employee benefit plans; references to "fines" shall include any excise taxes
assessed on a Person with respect to an employee benefit plan; and references to
serving at the request of any business entity shall include any service as a
director, trustee, member, manager, officer, employee or agent of such business
entity which imposes duties on, or involves services by, such director, trustee,
member, manager, officer, employee or agent with respect to an employee benefit
plan, its participants, or beneficiaries.

     SECTION 18. New Members; Assignment and Issuance of Membership Units.

     (a) New Members. A Person, including, without limitation, an assignee of
any Membership Units, shall be admitted as a Member only upon (i) the approval
of the Managers, (ii) the approval of the Majority Interest and (iii) the
execution by such Person of this Agreement.

     (b) Assignment of Membership Units. Membership Units may be assigned, in
whole or in part, only upon (i) the approval of the Managers, (ii) the approval
of the Majority Interest and (iii) if the assignee is not already a Member, the
execution by such Person of this Agreement. Any attempted assignment in
contravention of this Section 18(b) shall entitle the assignee to receive such
distributions, to share in such profits and to receive such allocations of
income, gain, loss, deduction, credit, tax preference and similar items to which
the assignor was entitled to the extent assigned, but shall not entitle the
assignee to become a Member or to exercise any rights or powers of a Member with
respect to such Membership Units. Until the conditions in the first sentence of
this Section 18(b) are fulfilled, the assignor, subject to the preceding
sentence, shall continue to be a Member and be entitled to exercise the rights
and powers of a Member with respect to such Membership Units.

     (c) Issuance of Additional Membership Units. The Company may issue
additional Membership Units to a Person upon (i) the making of a Capital
Contribution by such Person, (ii) the approval of the Managers, (iii) the
approval of the Majority Interest and (iv) if the assignee is not already a
Member, the execution by such Person of this Agreement.

     (d) Amendment of Schedule. Upon any admission of a new Member or any
assignment or issuance of Membership Units in accordance with the provisions of
this Section 18, the Managers shall amend, modify or supplement Schedule I
attached hereto as appropriate to reflect such admission, assignment or
issuance.

     SECTION 19. Dissolution.

     (a) Events of Dissolution. The Company shall be dissolved and terminated
upon the happening of the first to occur of any of the following events:



          (i) The adoption by a majority of the Managers then in office of a
     resolution declaring the advisability of the dissolution and termination of
     the Company, followed by the approval of such resolution by the Majority
     Interest;

          (ii) The authorization of the dissolution and termination of the
     Company by written consent of all of the Members; and

          (iii) Judicial dissolution pursuant to the Act.

     (b) Automatic Continuation. The Company shall automatically continue
without any action on the part of the Members upon the death, retirement,
withdrawal, resignation, expulsion, bankruptcy (as defined in Section 18-304 of
the Act) or dissolution of a Member or other event which terminates the
continued membership of a Member until the Company is otherwise dissolved and
terminated pursuant to the terms of this Agreement.

     SECTION 20. Winding Up and Distribution of Assets.

     (a) Winding Up. If the Company is dissolved, the Managers shall wind up the
affairs of the Company.

     (b) Distribution of Assets. Upon the winding up of the Company, the
Managers shall pay or make reasonable provision to pay all claims and
obligations of the Company, including, without limitation, (i) all claims of and
obligations to Members in their capacities as creditors, (ii) all costs and
expenses of the liquidation and (iii) all contingent, conditional, or unmatured
claims and obligations that are known to the Managers, whether the identity of
the claimant is known or unknown. If there are sufficient assets, such claims
and obligations shall be paid in full and any such provision shall be made in
full. If there are insufficient assets, such claims and obligations shall be
paid or provided for according to their priority and, among claims and
obligations of equal priority, ratably to the extent of assets available
therefor. Any remaining assets shall be distributed to Members pro rata in
accordance with their respective Membership Units.

     SECTION 21. Conflict of Interest. No Member shall be required to act
hereunder as its sole and exclusive business activity and any Member may have
other business interests and engage in other activities in addition to those
relating to the Company. Neither the Company nor any other Member shall have any
right by virtue of this Agreement in or to any such other interests or
activities or to the income or proceeds derived therefrom. A Member may transact
business with the Company and, subject to applicable laws, has the same rights
and obligations with respect thereto as any other Person. No transaction between
a Member and the Company shall be voidable solely because a Member has a direct
or indirect interest in the transaction if the transaction is fair and
reasonable to the Company or if the Majority Interest authorizes, approves or
ratifies the transaction.



     SECTION 22. No Partnership; No Separate Entity. The Members intend that the
Company not be treated as or construed to be a partnership (including, without
limitation, a limited partnership) or joint venture for purposes of the laws of
any state, including, without limitation, with respect to any party enjoying
express third party beneficiary rights hereunder, and that no Member will be
treated as a partner or joint venturer of any other Member, for any purposes,
other than for purposes of applicable United States tax laws, and this Agreement
may not be construed to suggest otherwise. For United States federal and (where
permitted) state income tax purposes, during such time as the Company is owned
by only one Member, the Company and the Members desire and intend that the
Company be disregarded as an entity separate from its then sole Member under
Treasury Regulation 301.7701-3(b)(1)(ii).

     SECTION 23. Taxation.

     (a) Tax Elections. The Managers shall not, without the unanimous consent of
the Members, cause the Company to make an election to be classified as a
corporation for federal or state income tax purposes. The Managers shall, upon
the written request of any Member benefitted thereby, cause the Company to file
an election under Section 754 of the Code and the Treasury Regulations
thereunder to adjust the basis of the Company assets under Section 734(b) or
743(b) of the Code and a corresponding election under the applicable sections of
state and local law. Each of the Managers shall have the authority to make all
other Company elections permitted under the Code, including elections of methods
of depreciation.

     (b) Company Tax Returns. The Managers shall cause the necessary tax returns
and information returns for the Company to be prepared. Each Member shall
provide such information, if any, as may be needed by the Company for purposes
of preparing such tax returns and information returns. The Managers shall
deliver to each Member such information required by such Member to enable such
Member to prepare and file its United States federal and state income tax
returns reflecting the operations of the Company.



     (c) Tax Audits.

          (i) During such time that the Company is owned by only one Member,
     this Subsection 23(c) shall be inapplicable. ONES LP shall be the "tax
     matters partner" of the Company pursuant to Section 6231(a)(7) of the Code
     (the "Tax Matters Member"). Any cost or expense incurred by the Tax Matters
     Member in connection with its duties, including the preparation for or
     pursuance of administrative or judicial proceedings, shall be paid by the
     Company.

          (ii) If at any time the Tax Matters Member cannot or elects not to
     serve as the Tax Matters Member, is removed by the Members as the Tax
     Matters Member or ceases to be a Member, the Majority Interest shall select
     another Member to be the Tax Matters Member. The Tax Matters Member, as an
     authorized representative of the Company, shall direct the defense of any
     claims made by the IRS to the extent that such claims relate to the
     adjustment of Company items at the Company level. The Tax Matters Member
     shall promptly deliver to each other Member a copy of any notice of
     beginning of administrative proceedings or any report explaining the
     reasons for a proposed adjustment received from the IRS relating to or
     potentially resulting in an adjustment of Company items. The Tax Matters
     Member shall, unless the Majority Interest consents to the contrary,
     diligently and in good faith contest any proposed adjustment of a Company
     item that principally affects the Members at the administrative and
     judicial levels, including, if appropriate or if requested by the Majority
     Interest, appealing any adverse judicial decision, and shall consider in
     good faith any suggestions made by any other Member or its counsel
     regarding the conduct of such administrative or judicial proceedings. The
     Tax Matters Member shall keep each other Member advised of all material
     developments with respect to any proposed adjustment that come to its
     attention, including, without limitation, the scheduling of all conferences
     and substantive telephone calls with the IRS. Each Member shall be
     entitled, at its own expense, to attend all meetings with the IRS and to
     review in advance any material written information (including, without
     limitation, any pleadings, memoranda or similar items) to be submitted to
     the IRS. Without first obtaining the consent of the Majority Interest, the
     Tax Matters Member shall not, with respect to any proposed adjustment of a
     Company item that materially and adversely affects any Member, (A) enter
     into a settlement agreement that purports to bind Members other than the
     Tax Matters Member (including, without limitation, any stipulation
     consenting to an entry of decision by any tax court), or (B) enter into an
     agreement or stipulation extending the statute of limitations.

          (iii) The Company shall promptly deliver to each Member a copy of all
     notices, communications, reports or writings of any kind with respect to
     income or similar taxes received from any state or local taxing authority
     relating to the Company that might materially and adversely affect each
     Member, and shall keep such Members



     advised of all material developments with respect to any proposed
     adjustment of Company items that come to its attention.

          (iv) Each Member shall continue to have the rights described in this
     Section 23(c) with respect to tax matters relating to any period during
     which it was a Member, whether or not it is a Member at the time of the tax
     audit or contest.

     SECTION 24. Miscellaneous.

     (a) Governing Law. This Agreement and any controversies or claims hereunder
shall be governed by and construed in accordance with the laws of the State of
Delaware, without regard to its conflict of law rules.

     (b) Binding Effect. Except as otherwise specifically provided herein, this
Agreement shall be binding upon and inure to the benefit of the parties and
their legal representatives, heirs, administrators, executors, successors and
assigns.

     (c) Pronouns and Number. Wherever from the context it appears appropriate,
each term stated in either the singular or the plural shall include the singular
and the plural, and pronouns stated in either the masculine, the feminine or the
neuter gender shall include the masculine, feminine and neuter. Without limiting
the generality of the foregoing, references in this Agreement to "Members" and
"Managers" shall, at any time that the Company has a single Member or Manager,
respectively, be deemed to refer solely to such Member or Manager, respectively.

     (d) Captions. Captions or section headings contained in this Agreement are
inserted only as a matter of convenience and in no way define, limit or extend
the scope or intent of this Agreement or any provision hereof.

     (e) Enforceability. If any provision of this Agreement, or the application
of the provision to any Person or circumstance, shall be held invalid or
unenforceable, the remainder of this Agreement, or the application of that
provision to Persons or circumstances other than those with respect to which it
is held invalid or unenforceable, shall not be affected thereby.

     (f) Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original but all of which shall
constitute one and the same instrument.

     (g) Notices. Any notices permitted or required under this Agreement shall
be deemed to have been given when delivered in Person or by courier or three (3)
days after being deposited in the United States mail, postage prepaid, and
addressed to the Company at its principal place of business and to any Member at
the address reflected on the books and records of the Company. Whenever any
notice is required to be given under law or the provisions of this Agreement, a
waiver thereof in writing, signed by the Person or Persons entitled to said
notice, whether before or after the time stated therein, shall be deemed
equivalent to notice.



     (h) Entire Agreement; Amendment. This Agreement constitutes the entire
agreement between the parties hereto with respect to the matters set forth
herein and supersedes all prior understandings or agreements between the parties
with respect to such matters. This Agreement may be amended at any time and from
time to time by resolution of the Majority Interest.

     (i) Further Assurances. The Members shall execute and deliver such further
instruments and do such further acts and things as may be required to carry out
the intent and purposes of this Agreement. Each Member shall execute all such
certificates and other documents and shall do all such filing, recording,
publishing, and other acts as the Managers deem appropriate to comply with the
requirements of law for the conversion and operation of the Company and to
comply with any laws, rules, and regulations relating to the acquisition,
operation, or holding of the property of the Company.

     (j) Third Parties. Except as provided in Section 17, nothing in this
Agreement, whether express or implied, shall be construed to give any Person
other than a Member or the Company any legal or beneficial or other equitable
right, remedy or claim under or in respect of this Agreement, any covenant,
condition, provision or agreement contained herein or the property of Company.

     (k) Facsimile Signatures. The facsimile signature of any Manager or Member
may be used at all times and for all purposes in place of an original signature.

     (l) Reliance upon Books, Reports and Records. Unless he or she has
knowledge concerning the matter in question which makes his or her reliance
unwarranted, each Manager shall, in the performance of his or her duties
hereunder, be entitled to rely on information, opinions, reports or statements,
including, without limitation, financial statements and other financial data, if
prepared or presented by one or more employees of the Company or by legal
counsel, accountants or other Persons as to matters such Manager reasonably
believes to be within such Person's professional or expert competence.

     (m) Waiver. No failure by the Company, any Manager or Member to insist upon
the strict performance of any covenant, duty, agreement or condition of this
Agreement or to exercise any right or remedy consequent upon a breach thereof
shall constitute waiver of any such breach or any other covenant, duty,
agreement or condition.



     IN WITNESS WHEREOF, the undersigned Members have executed this Agreement as
of the date first set forth above.

ONDEO NALCO ENERGY SERVICES, L.P.

By: Ondeo Nalco Energy Services, Inc.,
    its General Partner


By:
    ----------------------------------------
Name: Mark Bosanko
Title: Chief Executive Officer and President



                                   SCHEDULE I

                                     MEMBERS

Name and Address                    Capital Contribution   Membership Units
----------------                    --------------------   ----------------
Ondeo Nalco Energy Services, L.P.           $100                  100
Ondeo Nalco Center
Naperville, IL 60563