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                                                                    Exhibit 10.3

                          TEXAS GENCO RETIREMENT TRUST

                  (As Established Effective September 1, 2004)

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                          TEXAS GENCO RETIREMENT TRUST

                  (As Established Effective September 1, 2004)

                                   I N D E X

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ARTICLE I     DEFINITIONS AND CONSTRUCTION...........................................................     2
   1.1        Definitions............................................................................     2
   1.2        Construction...........................................................................     3

ARTICLE II    TRUST; GENERAL DUTIES OF THE PARTIES...................................................     4
   2.1        Establishment of Trust.................................................................     4
   2.2        General Duties of the Company:.........................................................     4
   2.3        Investment Guidelines; Contributions; Employee Records.................................     4
   2.4        General Duties of Trustee..............................................................     4

ARTICLE III   ACCOUNTS; AUTHORITY OF COMPANY AND COMMITTEE...........................................     6
   3.1        Accounts; Valuation....................................................................     6
   3.2        Exclusive Benefit of Employees the Plan................................................     7
   3.3        Authority of Company and Committee.....................................................     7

ARTICLE IV    INVESTMENT, ADMINISTRATION AND DISBURSEMENT OF TRUST FUND..............................     8
   4.1        Investment of Trust Fund...............................................................     8
   4.2        Direction of Investment................................................................    10
   4.3        Insurance or Annuity Contracts.........................................................    13
   4.4        Voting of Securities...................................................................    15
   4.5        Powers of Trustee......................................................................    15
   4.6        Payments and Distributions from Trust Fund.............................................    17
   4.7        Trustee's Dealings with Third Parties..................................................    18
   4.8        Ancillary Trustee......................................................................    18

ARTICLE V     FOR THE PROTECTION OF THE TRUSTEE......................................................    19
   5.1        Composition of Committee...............................................................    19
   5.2        Evidence of Action by Company or Committee.............................................    19
   5.3        Communications.........................................................................    20
   5.4        Advice of Counsel......................................................................    20
   5.5        Miscellaneous..........................................................................    20
   5.6        Fiduciary Responsibilities:............................................................    20

ARTICLE VI    TAXES, EXPENSES AND COMPENSATION OF TRUSTEE............................................    22
   6.1        Taxes and Expenses.....................................................................    22
   6.2        Compensation of the Trustee............................................................    22
</TABLE>

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<S>                                                                                                      <C>
ARTICLE VII   SETTLEMENT OF ACCOUNTS; DETERMINATION OF INTERESTS UNDER TRUST.........................    23
   7.1        Settlement of Accounts of Trustee......................................................    23
   7.2        Determination of Rights and Benefits of Persons Claiming an Interest in the
              Trust Fund; Enforcement of Trust Fund .................................................    24

ARTICLE VIII  RESIGNATION, REMOVAL AND SUBSTITUTION OF THE TRUSTEE...................................    25
   8.1        Resignation of Trustee.................................................................    25
   8.2        Removal of Trustee.....................................................................    25
   8.3        Appointment of Successor Trustee.......................................................    25
   8.4        Transfer of Trust Fund to Successor....................................................    25

ARTICLE IX    DURATION AND TERMINATION OF TRUST; AMENDMENT...........................................    26
   9.1        Duration and Termination...............................................................    26
   9.2        Distribution Upon Termination..........................................................    26
   9.3        Certain Withdrawals....................................................................    26
   9.4        Amendment..............................................................................    27

ARTICLE X     MISCELLANEOUS..........................................................................    28
   10.1       Governing Law; No Bond Required of Trustee.............................................    28
   10.2       Interest in Trust Fund; Assignment.....................................................    28
   10.3       Invalid Provisions.....................................................................    28
   10.4       Remedies...............................................................................    28
   10.5       Prohibition of Diversion...............................................................    28
   10.6       Headings for Convenience Only..........................................................    28
   10.7       Successors and Assigns.................................................................    28
</TABLE>

                                       ii
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                          TEXAS GENCO RETIREMENT TRUST

                  (As Established Effective September 1, 2004)

            THIS TRUST AGREEMENT made and entered into as of the 1st day of
September, 2004, by and between TEXAS GENCO, LP, a Texas limited partnership
(the "Company"), and THE NORTHERN TRUST COMPANY, an Illinois corporation, as
trustee (the "Trustee");

                              W I T N E S S E T H:

            WHEREAS, the Company, in connection with its establishment of the
Texas Genco Retirement Plan, effective as of September 1, 2004 (the "Plan"), for
the benefit of eligible employees of the Company and its affiliates, desires to
establish a trust to fund the benefits accrued under the Plan and to provide for
the investment of the assets of the trust fund; and further

            WHEREAS, the assets transferred to the trust established hereunder
and those to be transferred from time to time, shall constitute a trust fund to
be held hereunder; and further

            WHEREAS, the Trustee is willing to hold and administer such trust
assets pursuant to the terms of this Trust Agreement.

            NOW, THEREFORE, the Trustee accepts the trust created hereby and
covenants that it will hold all property which it may receive hereunder, IN
TRUST, upon the terms and conditions hereinafter stated; and the parties hereto
agree as follows:

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                                   ARTICLE I

                          DEFINITIONS AND CONSTRUCTION

      1.1   Definitions: As used in the Trust, the following words and phrases
shall have the following meanings unless the context clearly requires a
different meaning:

            AFFILIATE: The Company and (i) any other corporation or trade or
      business which, together with the Company, is in the same "controlled
      group" or "under common control" within the meaning of Section 414(b) or
      (c) of the Code and (ii) any organization (whether or not incorporated)
      which is a member of an "affiliated service group" within the meaning of
      Section 414(m) of the Code, which includes the Company.

            CODE: The Internal Revenue Code of 1986, as from time to time
      amended.

            COMMITTEE: The General Partner or a committee appointed by the
      General Partner, which shall serve as a "named fiduciary" hereunder and
      assist in the administration of the Trust Fund and whose duties also
      include the administration of the Plan.

            COMPANY: Prior to the consummation date of "Genco LP Division," as
      described in Section 2.1 of that certain Transaction Agreement among
      CenterPoint Energy, Inc., Utility Holding, LLC, NN Houston Sub, Inc.,
      Texas Genco Holdings, Inc., HPC Merger Sub, Inc. and GC Power Acquisition
      LLC, dated as of July 21, 2004, Texas Genco, LP, a Texas limited
      partnership, and, on and after the consummation date the Genco LP
      Division, Texas Genco II, LP, a Texas limited partnership.

            ERISA: The Employee Retirement Income Security Act of 1974, as from
      time to time amended.

            GENERAL PARTNER: The general partner of the Company.

            GROUP TRUST: Any common, collective, group or commingled trust
      selected by the Committee which is qualified under Code Section 401(a) and
      exempt from tax under Code Section 501(a).

            INSURANCE CONTRACTS: The insurance and annuity contracts as provided
      in Section 4.2 hereof.

            INVESTMENT MANAGER: The fiduciary or fiduciaries, if any, appointed
      hereunder by the Committee and meeting the definition set forth in Section
      3(38) of ERISA.

            PARTICIPANT: Each employee, former employee, spouse or beneficiary
      of an employee who is or was participating in the Plan in accordance with
      the terms thereof.

            PLAN: The Texas Genco Retirement Plan, as established effective
      September 1, 2004, and as thereafter amended.

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            TRUST: The Texas Genco Retirement Trust, as established effective
      September 1, 2004, and as thereafter amended.

            TRUST FUND: The fund or funds to be established under the Trust and
      from which benefits under the Plan are to be paid. Such fund shall consist
      of all assets, money and property, all investments made therewith and
      proceeds thereof and all earnings and profits thereon, less the payments
      or other distributions which, at the time of reference, shall have been
      made by the Trustee, as authorized herein.

            TRUSTEE: The Northern Trust Company, an Illinois corporation, and
      its successors, which shall carry out its duties hereunder as a
      "fiduciary" as provided in Section 3(21) of ERISA and shall have
      discretion and authority as set fort herein.

            VALUATION DATE: The close of business on the last business day of
      each calendar month and any such other date or dates as the Committee may
      deem appropriate; provided, however, that any such interim valuation shall
      be exercised on a uniform and non-discriminatory basis.

      1.2   Construction: The masculine gender, where appearing in the Trust,
shall be deemed to include the feminine gender, and the singular may include the
plural, unless the context clearly indicates to the contrary. The words
"hereof," "herein," "hereunder" and other similar compounds of the words "here"
shall mean and refer to the entire Trust, not to any particular provision or
section. Article and Section headings are included for convenience of reference
and are not intended to add to or subtract from the terms of the Trust.

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                                   ARTICLE II

                      TRUST; GENERAL DUTIES OF THE PARTIES

      2.1   Establishment of Trust: The Company hereby establishes with the
Trustee a Trust for the exclusive purpose of providing benefits to employees of
the Company and Affiliates that participate in the Plan, and to the
beneficiaries of such employees, under the Plan and defraying reasonable
expenses of administering the Plan. The Trust shall consist of (a) such cash and
other property held in trust under the CenterPoint Energy, Inc. Retirement Trust
Agreement on behalf of employees of the Company and which was transferred to the
Trust at the close of business on September 1, 2004, and (b) such sums of money
and such property acceptable to the Trustee as shall from time to time be paid
or delivered to the Trustee as a contribution in respect of the Plan, together
with the income and gains therefrom. The Trust shall be maintained at all times
as a domestic trust in the United States.

      2.2   General Duties of the Company: The Company shall provide the Trustee
with evidence acceptable to the Trustee that the Plan has been duly adopted by
the Company and is intended to be qualified under Code Section 401(a).

            The General Partner shall appoint a Benefits Committee, consisting
of at least three individuals, which shall be authorized under the Plan to serve
as a "named fiduciary" (within the meaning of Section 402(a)(2) of ERISA) of the
Plan to assist in the administration of the Trust as hereinafter provided. Each
member of the Committee shall serve at the pleasure of the General Partner and
the General Partner shall certify to the Trustee the names and specimen
signatures of the members of the Committee serving from time to time hereunder.
The Company shall indemnify and hold harmless each member of the Committee from
any and all claims, losses, damages, expenses (including counsel fees approved
by the Committee), and liabilities (including any amounts paid in settlement
with the Committee's approval but excluding any excise tax assessed against any
member or members of the Committee pursuant to the provisions of Code Section
4975) arising from any act or omission of such member in connection with his
duties and responsibilities under this Trust Agreement, except when the same is
judicially determined to be due to the gross negligence and willful misconduct
of such member.

      2.3   Investment Guidelines; Contributions; Employee Records: From time to
time the Committee shall communicate in writing to any Investment Manager who
may be acting pursuant to Section 4.2 (and to the Trustee, if it is managing the
investment of any of the assets of the Trust pursuant to such Section) the
investment guidelines governing the portion of the assets of the Trust managed
by such Investment Manager or the Trustee. The Company shall make, and shall
cause the Affiliates to make, contributions to the Plan as the same may be
allowed in accordance with the Plan and applicable law and shall specify in
writing to the Trustee the amount of such contributions. The Company shall keep
and shall cause the Affiliates to keep accurate books and records with respect
to their respective employees, including, without limitation, records as to the
periods of employment, compensation and ages of such employees.

      2.4   General Duties of Trustee: The Trustee shall hold all property
received by it hereunder, which, together with the income and gains therefrom
and additions thereto, and less payments and other distributions therefrom,
shall constitute the Trust Fund. Except as otherwise

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hereinafter provided, the Trustee shall manage, invest and reinvest the Trust
Fund, collect the income thereof, and make payments therefrom, all in accordance
with the terms of this Trust Agreement. The Trustee shall be responsible only
for the property actually received by it hereunder. It shall have no duty or
authority to compute any amount to be paid to it by the Company or by any
Affiliate, or to bring any action or proceeding to enforce the collection from
any such person of any contribution to the Trust in respect of the Plan.

                                       5
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                                   ARTICLE III

                                    ACCOUNTS;
                       AUTHORITY OF COMPANY AND COMMITTEE

      3.1   Accounts; Valuation: The Trustee shall determine the value of the
assets of the Trust Fund as of each Valuation Date. Each such valuation shall be
made as promptly as practicable after the Valuation Date as of which it is made.
Each contribution to and payment and distribution from the Fund shall be made as
of the Valuation Date next preceding the date on which, as applicable, the
Trustee receives such contribution or receives notice from the Company or the
Committee that such payment or distribution is to be made, on the basis of the
valuation of the Trust Fund as of such Valuation Date (taking into account the
liabilities of the Trust Fund as of such Date).

            At the close of business on the Valuation Date, the Trustee shall
render to the Committee a statement of account for the Trust Fund using its
pricing services for each respective type of security. In the absence of a
readily ascertainable value, the Trustee shall rely conclusively on the
determination of any Investment Manager (or the Committee if it has
responsibility for a portion of the Trust Fund) with respect to the fair market
value of those assets allocated to such Investment Manager (or the Committee),
and the Trustee shall have no responsibility with respect to the determination
of the fair market value of such assets. Notwithstanding any other provision of
this Section, the Committee or its agent, may rely upon the determination of the
issuer of any insurance contract held as part of the Trust Fund with respect to
the value of such contract and may rely upon the determination of any Investment
Manager with respect to the value of any interest of the Trust in any common,
collective, commingled or group trust fund maintained by such Investment Manager
in which assets of the Trust are permitted to be invested by Section 4.5(j) of
this Trust Agreement.

            Any Investment Manager or the Committee who may be acting pursuant
to Section 4.2 (and the Trustee, if it is managing the investment of any assets
of the Trust pursuant to such Section) may in its discretion transfer or direct
the transfer to a liquidating account of any investment of the portion of the
Trust under its management which it determines should be liquidated for the
benefit of the Plan. Any investment that has been transferred to a liquidating
account shall be segregated and administered or realized upon solely for the
benefit of the Plan and shall be excluded in determining the value of the Plan
in the Trust Fund thereafter.

            Notwithstanding the foregoing requirements of this Section 3.1, the
Committee may direct the Trustee to establish and maintain a "Welfare Benefits
Account" or a "Post-Retirement Medical Benefit Account" within the Trust Fund
for the Plan (hereinafter referred to as a "Post-Retirement Medical Benefit
Account"). Such Post-Retirement Medical Benefit Account shall be maintained for
the sole purpose of paying certain medical claims incurred by retired employees
who are entitled to pension benefits under the Plan and their eligible
dependents in accordance with Section 401(h) of the Code. The assets of such
Post-Retirement Medical Benefit Account shall be separately accounted for on the
Trustee's books and records as a part of the Plan but may be commingled and
invested with other assets of the Trust Fund at the Committee's discretion.
Additions to a Post-Retirement Medical Benefit Account may be contributions from
the Company or an Affiliate or by the transfer(s) of assets from the portion of

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the Plan which is not accounted for on the Trustee's books and records as a
Post-Retirement Medical Benefit Account, as directed by the Committee, which
direction shall be in accordance with Section 420 of the Code. The Committee
shall designate the contributions which are allocable to a Post-Retirement
Medical Benefit Account and shall designate the portion of the assets
attributable to the Plan which are not accounted for on the Trustee's books and
records as a Post-Retirement Medical Benefit Account that is to be transferred
to the Post-Retirement Medical Benefit Account maintained within the Plan. The
Trustee shall make the payments from a Post-Retirement Medical Benefit Account
at the written direction of the Committee, which direction shall be pursuant to
the Plan document and in accordance with Section 420 of the Code and other
applicable law. Such direction may provide for the direct reimbursement of the
Company or an Affiliate Corporation from the Post-Retirement Medical Benefit
Account for certain expenses the Company or an Affiliate Corporation has
previously paid to provide post-retirement medical plan coverage to retired
employees who are entitled to pension benefits under the Plan and their eligible
dependents. Upon the Committee's determination that all liabilities for benefit
payments under a Post-Retirement Medical Benefit Account have been satisfied,
the Committee shall direct the Trustee in writing to remit any remaining amounts
credited to such Account to the Company or one or more Affiliates, except to the
extent that such remaining amounts are attributable to a transfer of assets from
the portion of the Plan which does not constitute a Post-Retirement Medical
Benefit Account, in which event such remaining amounts shall be transferred back
to such other portion of the Plan.

      3.2   Exclusive Benefit of Employees the Plan: At no time prior to the
satisfaction of all liabilities with respect to employees and their
beneficiaries under the Plan shall any part of the Trust Fund be used for, or
diverted to, any purposes other than for the exclusive benefit of such employees
and their beneficiaries or the payment of Plan or Trust administrative expenses.

      3.3   Authority of Company and Committee: Any Affiliates which
participates in the Plan shall be bound by the decisions, instructions, actions
and directions of the Company, the Committee (or its representative), and each
Investment Manager under this Trust Agreement and the Trustee shall be
indemnified by the Company and such Affiliate for expenses and liabilities
incurred by relying upon such decisions, instructions, actions and directions,
or in the event such expenses or liabilities were incurred by the Trustee due to
the failure of such parties to carry out their responsibilities under the Plan.
The Trustee shall not be required to give notice to or obtain the consent of any
such Affiliate with respect to any action which is taken by the Trustee pursuant
to this Trust Agreement.

                                       7
<PAGE>

                                   ARTICLE IV

                         INVESTMENT, ADMINISTRATION AND
                           DISBURSEMENT OF TRUST FUND

      4.1   Investment of Trust Fund: Except as provided elsewhere in this Trust
Agreement, the Trust Fund may be invested, in accordance with the procedures
prescribed by Section 4.2, in any property, real, personal or mixed, wherever
situated, and whether or not productive of income or consisting of wasting
assets, including, without limitation, (i) common and preferred stocks, bonds,
notes and debentures (including convertible stocks and securities but not
including any stocks or securities of the Trustee or its affiliates), (ii)
leaseholds, mortgages (including, without limitation, any collective or part
interest in any bond and mortgage or note and mortgage), (iii) certificates of
deposit, demand or time deposits (including any such deposit with any bank
serving as trustee hereunder), (iv) shares of investment companies and mutual
funds, (v) interests in partnerships, trusts and limited liability companies,
insurance policies and contracts (including individual or group annuity
contracts), (vi) oil, mineral or gas properties, royalties, interests or rights
(including equipment pertaining thereto), without being limited to the classes
of property in which trustees are authorized to invest trust funds by any law,
or any rule of court, of any state and without regard to the proportion any such
property may bear to the entire amount of the Trust Fund, and (vii) any Group
Trust and the Trustee may cause the assets of the Trust Fund to be invested as
part of the funds created pursuant to the agreements of trust establishing any
Group Trust, subject to all of the provisions of said agreements of trust, such
agreements of trust being herein incorporated by this reference as fully as if
set forth herein; provided, however, that (i) investments shall be so
diversified as to minimize the risk of large losses unless under the
circumstances it is clearly prudent not to do so, in the sole judgment of the
person who is directing the investment of the Trust Fund under the provisions of
Section 4.2, or in the sole judgment of the Trustee if it is managing the Trust
Fund under such provisions and (ii) investments shall at all times be subject to
the limitations set forth in the next following paragraph.

            The Committee shall not direct the Trustee to invest any assets of
the Trust Fund in any Company security which is not a "qualifying Company
security" nor in any Company real property which is not "qualifying Company real
property." Moreover, the Committee shall not direct the Trustee to acquire any
"qualifying Company securities" and/or "qualifying Company real property" as an
investment if such acquisition will result in the Trust Fund holding more than
10% of the then fair market value of the assets of the Trust Fund in "qualifying
Company securities" and/or "qualifying Company real property." For purposes of
this paragraph, the term "qualifying Company securities" means stock or
marketable obligations of the Company or an Affiliate, as defined in Section 407
of ERISA. The term "qualifying Company real property" means parcels of real
property leased to the Company or an Affiliate if a substantial number of the
parcels are disbursed geographically and if each parcel is suitable for or
adaptable to more than one use, as defined in Section 407 of ERISA.

            The Committee shall have the sole investment responsibility with
respect to retention, sale, purchase or voting of any Company Stock which has
not been allocated to an Investment Manager. The Trustee shall have custody of
such Company Stock and shall act with respect thereto only as directed by the
Committee. The Trustee shall not make any investment

                                       8
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review of, consider the propriety of holding or selling, or vote any such
Company Stock. With respect to such Company Stock, the Committee shall have the
investment power granted to the Trustee by Section 4.5 as limited by 3.2 and 4.1
of this Trust Agreement, as if all references therein to the Trustee referred to
the Committee.

            To the extent that any portion of the Trust Fund is invested in
mutual fund shares or bank commingled funds, the Committee shall initially
select funds to be invested in and shall be responsible for retaining the
availability of or terminating the availability of such funds. To the extent the
Trustee is required to enter into a custody agreement with the sponsor of a bank
commingled fund or such other type of fund, the Committee shall direct the
Trustee to enter into such agreement.

            With the prior approval of the Committee, the Trustee or the person
directing the investment of a portion or all of the Trust Fund may utilize
investment practices and techniques which include but are not limited to (i)
securities lending, (ii) investments in futures contracts, forwards contracts
and options, (iii) swap agreements and (iv) indexed securities in which value is
linked to currencies, interest rates, commodities indices or other financial
indicators.

            With regard to the lending of securities, the Committee may direct
the Trustee as fiduciary to lend securities of the Trust Fund held by the
Trustee by entering into a written agreement with the Trustee. The terms of the
agreement between the Committee and the Trustee shall be consistent with
Department of Labor Prohibited Transaction Exemption 81-6 or any successor
exemption. The written agreement between the Committee and the Trustee shall
direct the Trustee to enter into a loan agreement with a borrower or borrowers.

            The Trustee shall transfer securities to the borrower and invest or
hold on behalf of the Trust Fund the collateral received in exchange for the
securities. Notwithstanding anything in this Trust Agreement to the contrary,
the borrower shall have the authority and responsibility to vote securities it
has borrowed. The Trustee shall maintain a record of the market value of the
loaned securities and shall be paid reasonable compensation as agreed to by the
Trustee and the Committee.

            With regard to investments in futures, the Committee may direct the
Trustee to: (i) enter into such agreements as are necessary to implement
investment in futures contracts and options on futures contracts; (ii) transfer
initial margin to a futures commission merchant or third party safekeeping bank
pursuant to directions from an Investment Manager and (iii) pay or demand margin
in accordance with industry practice to or from such futures commission merchant
based on daily mark to market calculations. The Trustee shall have no investment
or custodial responsibility with respect to assets transferred to a futures
commission merchant or third party safekeeping bank.

            Any property at any time received by the Trustee may be retained in
the Trust Fund. To the extent that the Trustee is managing the Trust Fund under
the provisions of Section 4.2, the Trustee may invest and reinvest all or any
portion of the Trust Fund collectively with funds of other pension and
profit-sharing trusts exempt from tax under Section 501(a) of the Code by reason
of qualifying under Section 401(a) of said Code either in obligations selected
by the Trustee or by investment collectively through the medium of any common,
collective or

                                       9
<PAGE>

commingled trust fund which has been or hereafter may be established by the
Trustee or by any other bank in the United States, the instrument or instruments
establishing such trust fund or funds, as amended from time to time, being made
a part of this Trust Agreement so long as any portion of the Trust Fund shall be
invested through the medium thereof.

            With respect to any portion of the Trust Fund which is under the
management of an Investment Manager or the Committee and except as otherwise
provided in this section with regard to the lending of securities, the Trustee
shall not make any investment review of, consider the propriety of holding or
selling, or vote other than as directed by an Investment Manager or the
Committee, any assets of the Trust Fund allocated to an Investment Manager or
the Committee in accordance with Section 4.2, except that if the Trustee shall
not have received contrary instructions from the Investment Manager or the
Committee, the Trustee shall invest for short term purposes any cash consisting
of U.S. dollars, for which an Investment Manager or the Committee has investment
responsibility, in its custody in the short-term collective investment fund
maintained by the Trustee. For currencies other than U.S. dollars, the Trustee
shall invest cash for which an Investment Manager or the Committee has
investment responsibility as directed by the Investment Manager or the Committee
with respect to those assets of the Trust Fund for which the Investment Manager
or the Committee has investment responsibility and such investments may include
an interest bearing account of a foreign custodian.

      4.2   Direction of Investment: The Committee shall from time to time
specify by written notice to the Trustee whether the investment of the Trust
Fund (other than the portion thereof consisting of Insurance Contracts), in the
manner provided in Section 4.1, shall be managed solely by the Trustee, or shall
be directed by one or more Investment Managers, or whether both the Trustee and
one or more Investment Managers are to participate in investment management and
if so how the investment responsibility is to be divided with respect to assets.
In the event that the Committee shall fail to specify pursuant to this Section
4.2 the person or persons who are to manage the investment of the Trust Fund or
any portion or portions thereof (other than the portion or portions consisting
of Insurance Contracts) the Trustee shall manage the Trust Fund or such portion
or portions pursuant to the investment guidelines established by the Committee
given in the exercise of that Committee's responsibility.

            Any Investment Manager appointed to manage the investment of a part
(or all) of the Trust Fund (other than the portion or portions thereof
consisting of Insurance Contracts) shall either (i) be registered as an
investment adviser under the Investment Advisers Act of 1940 or under the laws
of any state, (ii) be a bank, as defined in that Act or under the laws of any
state, or (iii) be an insurance company qualified to perform investment
management services under the laws of more than one state. If investment of the
Trust Fund (other than the portion or portions thereof consisting of Insurance
Contracts) is to be directed in whole or in part by an Investment Manager, the
Trustee shall be given copies of the instruments appointing the Investment
Manager and evidencing his acceptance of such appointment and acknowledgment
that he is a fiduciary of the Plan, and a certificate evidencing the Investment
Manager's registration under said Act or status as a bank or insurance company
described in the next preceding sentence. The Trustee may continue to rely upon
such instruments and certificate until otherwise notified in writing by the
Committee.

                                       10
<PAGE>

            The Trustee shall follow the directions of the Investment Manager
regarding the investment and reinvestment of the portion or portions of the
Trust Fund as shall be under management by the Investment Manager, and shall be
under no duty or obligation to review any investment to be acquired, held or
disposed of pursuant to such directions nor to make any recommendations with
respect to the disposition or continued retention of any such investment. The
Trustee shall have no liability or responsibility for acting without question on
the direction of, or failing to act in the absence of any direction from, the
Investment Manager, unless the Trustee participated knowingly in or knowingly
undertook to conceal an act or omission of an Investment Manager knowing such
act or omission to be a breach of fiduciary responsibility. The processing of
investment orders by the Trustee pursuant to the direction of an Investment
Manager shall not constitute participating knowingly.

            The Investment Manager at any time and from time to time may issue
orders for the purchase or sale of securities directly to a broker, and in order
to facilitate such transaction the Trustee upon request shall execute and
deliver appropriate trading authorizations. Written notification of the issuance
of each such order shall be given promptly to the Trustee by the Investment
Manager, and the execution of each such order shall be confirmed to the Trustee
by the broker. Such notification shall be authority for the Trustee to pay for
securities purchased against receipt thereof and to deliver securities sold
against payment therefor, as the case may be. All notifications concerning
investments made by the Investment Manager shall be signed by such person or
persons, acting on behalf of the Investment Manager as may be duly authorized in
writing; provided, however, that the transmission to the Trustee of such
notifications by photostatic teletransmission with duplicate or facsimile
signature or signatures shall be considered a delivery in writing of the
aforesaid notifications until the Trustee is notified in writing by the
Investment Manager that the use of such devices with duplicate or facsimile
signatures is no longer authorized. The Trustee shall be entitled to rely upon
such directions which it receives by such means if so authorized by the
Investment Manager and shall in no way be responsible for the consequences of
any unauthorized use of such device which was not, in fact, known by the Trustee
at the time to be unauthorized. The Trustee shall, as promptly as possible,
comply with any written directions given by the Investment Manager hereunder,
and, where such directions are given by photostatic teletransmission with
facsimile signature or signatures, the Trustee shall be entitled to presume any
directions so given are fully authorized.

            In the event that an Investment Manager should resign or be removed
by the Committee, the Trustee shall, upon receiving written notice of such
resignation or removal, manage, pursuant to Section 4.1, the investment of the
portion of the Trust Fund under management by such Investment Manager at the
time of its resignation or removal, unless and until it shall be notified of the
appointment of another Investment Manager as provided in this Section 4.2, for
such portion of the Trust Fund.

            At any time and from time to time, the Committee may direct the
Trustee to transfer a specified portion or all of the Trust Fund as it shall
deem advisable to the trustees of a Group Trust, if and only if a Group Trust is
qualified under Code Section 401(a) and exempt from tax under Code Section
501(a), and is maintained as a medium for the commingled, collective and common
investment of assets of eligible participating trusts; and the Committee may
direct the Trustee to withdraw all or any part of the Trust Fund so transferred.
The terms and provisions of the agreements of trust establishing the Group
Trusts and the provisions of any

                                       11
<PAGE>

amendments thereto, are hereby incorporated herein by reference and shall be
deemed a part of this Trust Agreement so long as any portion of the Trust Fund
shall be invested through the medium thereof. The Trustee shall make any such
transfer or withdrawal of all or any part of the Trust Fund only upon the
express direction of the Committee. The Trustee shall be under no duty or
obligation to review any investment acquired, held or disposed of by the
trustees of a Group Trust pursuant to the provisions thereof, nor shall the
Trustee be under a duty or obligation to review any investment acquired, held or
disposed of by the duly appointed trustees of any Group Trust pursuant to the
provisions establishing said Group Trust, and said trustees shall have all
fiduciary powers, responsibilities and liabilities arising under this Trust
Agreement with respect to the portion of the Trust Fund transferred to them
pursuant to the Committee's directions to be held under the terms and provisions
of the Group Trust. The Company shall indemnify and hold harmless the Trustee
from any and all claims, losses, damages, expenses (including counsel fees
approved by the Trustee) and liabilities (including any amounts paid in
settlement with the Trustee's approval but excluding any excise tax assessed
against the Trustee under Code Section 4975) arising from any act or omission of
the trustees of a Group Trust in connection with their duties and
responsibilities under this Trust Agreement with respect to the portion of Trust
Fund transferred to them, except to any extent prohibited under ERISA.

            The Trustee shall have custody of and custodial responsibility for
all assets of the Trust Fund except as otherwise provided in this Trust
Agreement or as follows:

            (a)   The subtrustee of a subtrust shall have custody of and
      custodial responsibility for any portion of the Trust Fund for which
      investment responsibility has been allocated to it by the Committee;

            (b)   The trustee of a collective or group trust fund (including
      without limitation an Investment Manager or its bank affiliate) shall have
      custody of and custodial responsibility for any portion of the Trust Fund
      for which investment responsibility has been allocated to it by the
      Committee and has been invested in such collective or group trust fund;
      and

            (c)   The Committee may direct in writing that the custody of
      additional assets of the Trust Fund (other than those referred to in
      paragraphs (a) and (b) immediately preceding this paragraph (c)) be
      maintained with one or more persons or entities designated by the
      Committee to maintain custody of assets of a portion of the Trust Fund (a
      "Custodial Agent"). In such event, the Committee shall approve, and direct
      the Trustee to enter into, a custody agreement with the Custodial Agent
      (which custody agreement may authorize the Custodial Agent to maintain
      custody of such assets with one or more subagents, including a broker or
      dealer registered under the Securities Exchange Act of 1934 or a nominee
      of such broker or dealer). The Custodial Agent shall have custodial
      responsibility for any assets maintained with the Custodial Agent or its
      subagents pursuant to the custody agreement. Notwithstanding any other
      provision of this Trust Agreement, the Company (which has the authority to
      do so under the laws of the state of Texas) agrees to indemnify the
      Trustee from any liability, loss and expense, including legal fees and
      expenses, which the Trustee may sustain by reason of acting in accordance
      with any directions of the Committee pursuant to this paragraph (c). This
      paragraph shall survive the termination of this Trust Agreement.

                                       12
<PAGE>

      4.3   Insurance or Annuity Contracts: With respect to the investment of
the Trust Fund in Insurance Contracts, the Committee shall direct the Trustee in
the exercise of the powers set forth in Section 4.2 and the Trustee shall
exercise such powers in the manner directed in writing by the Committee. It
shall be the duty of the Trustee to act strictly in accordance with each
direction of the Committee relating to the investment of the Trust Fund in
Insurance Contracts and the Trustee shall not have any duty to question any such
direction. The Trustee shall not have any duty to review any such Insurance
Contracts held in the Trust Fund pursuant to such direction, or to make
suggestions to the Committee with respect to the exercise or non-exercise of any
of the said powers. The Trustee shall be under no liability for any loss of any
kind which may result by reason of any action taken by it in accordance with any
direction of the Committee or by reason of its failure to exercise any of the
said powers in respect of such Insurance Contracts because of the failure of the
Committee to give such direction, unless the Trustee knows that by following
such direction it will be participating in a breach of fiduciary duty by the
Committee. The processing of investment orders or other ministerial tasks taken
by the Trustee pursuant to the direction of the Committee shall not constitute
knowledge.

            (a)   The Trustee, upon written direction of the Committee, shall
      pay from the Trust Fund such sums to such insurance company or companies
      or other financial institutions (collectively referred to as an "insurance
      company") as the Committee may direct for the purpose of procuring
      individual or group annuity contracts and/or policies or contracts of life
      insurance (hereinafter in this Section 4.3 referred to as "Contracts").
      The Committee shall prepare, or cause to be prepared in such form as it
      shall prescribe, the application for any Contract to be applied for under
      the Plan and this Trust and the Trustee shall execute such application.
      The Trustee shall receive and hold in the Trust Fund, subject to the
      provisions hereinafter set forth in this Section, all Contracts obtained
      pursuant to the Plan.

            (b)   The Trustee shall be the complete and absolute owner of
      Contracts held in the Trust Fund and, upon written direction of the
      Committee, shall have power, without the consent of any other person, to
      collect and receive all dividends or other payments of any kind payable
      with respect to any Contract held in the Trust Fund or to leave the same
      with the issuing insurance company; to convert from one form to another
      any Contract held in the Trust Fund; to change the person or persons
      designated in any Contract to receive the proceeds; to designate any mode
      of settlement of the proceeds of any Contract held in the Trust Fund; to
      sell or assign any Contract held in the Trust Fund; to surrender for cash
      any Contract held in the Trust Fund; to borrow sums of money from the
      issuing insurance company upon any Contract or Contracts issued by it and
      held in the Trust Fund, provided that the Trustee shall borrow such sums
      only in respect of all Contracts for the time being held in the Trust Fund
      and upon a uniform basis; to agree with the insurance company issuing any
      Contract to any release, reduction, modification or amendment thereof;
      and, without limitation of any of the foregoing, to exercise any and all
      of the rights, options or privileges that belong to the absolute owner of
      any Contract held in the Trust Fund or that are granted by the terms of
      any such Contract or by the terms of this Trust Agreement. The Trustee
      shall have no discretion with respect to the exercise of any of the
      foregoing powers or to take any other action permitted by any Contract
      held in the Trust Fund, but shall exercise such powers or take such action
      only upon the written direction of the Committee; the Trustee shall have
      no duty to exercise

                                       13
<PAGE>

      any of such powers or to take any such action unless and until it shall
      have received such direction. The Trustee, upon the written direction of
      the Committee, shall deliver any Contract held in the Trust Fund to such
      person or persons as may be specified in the direction.

            (c)   The Trustee shall hold in the Trust Fund the proceeds of any
      sale, assignment or surrender of any Contract held in the Trust Fund and
      any and all dividends and other payments of any kind received in respect
      to any Contract held in the Trust Fund, and shall distribute and/or
      allocate such proceeds in accordance with the directions of the Committee.

            (d)   If the Trustee shall have borrowed any sums of money upon any
      Contract held in the Trust Fund, it shall have no duty to repay any part
      of the money so borrowed, notwithstanding the fact that thereafter it may
      have sufficient funds to make such repayment, unless and until it shall
      have received written direction from the Committee to make the repayment.

            (e)   Upon the written direction of the Committee, the Trustee shall
      pay from the Trust Fund premiums, assessments, dues, charges and interest,
      if any, upon any Contract held in the Trust Fund. The Trustee shall have
      no duty to make any such payment unless and until it shall have received
      such direction. The written direction of the Committee to pay the premiums
      becoming due on any Contract specified in the direction shall be
      sufficient authority for the Trustee to pay any and all bills presented to
      it for premiums or the amount specified in any premium notice received
      from the insurance company issuing the Contract, and for such purposes the
      Trustee may use any money held by it as part of the Trust Fund at the time
      the payment is due, unless the Committee shall have directed that such
      money shall not be used for such purpose.

            (f)   Upon the direction of the Committee, the Trustee shall have
      power to execute all necessary receipts and releases to any insurance
      company issuing any Contract or Contracts held in the Trust Fund, and,
      upon written advice from the Committee that the proceeds of any Contract
      held in the Trust Fund have become payable, shall make reasonable efforts
      to collect such sums as may appear to be due; but the Trustee shall have
      no duty to begin or maintain any action, suit or legal proceeding to
      collect the proceeds of any Contract unless it is in possession of funds
      sufficient for the purpose or unless it has been indemnified to its
      satisfaction for its counsel fees, costs, disbursements and all other
      expenses and liabilities to which it in its judgment may be subjected by
      beginning or maintaining the action, suit or other legal proceeding. The
      Trustee may use the proceeds of any Contract held in the Trust Fund to
      defray the expenses incurred in connection with enforcing payment of that
      Contract. The Trustee shall have power, with the written approval of the
      Committee, to compromise and adjust claims arising out of any Contract
      held in the Trust Fund upon such terms and conditions as it may deem just,
      and the discretion of the Trustee shall be binding and conclusive upon all
      persons interested in the Trust Fund.

            (g)   Any insurance company may deal with the Trustee as sole owner
      of any Contract issued by it and held in the Trust Fund, without inquiry
      as to the authority of the

                                       14
<PAGE>

      Trustee to act, and may accept and rely upon any written notice,
      instruction, direction, certificate or other communication from the
      Trustee believed by it to be genuine and to be signed by an officer of the
      Trustee. No insurance company shall be required to look into the terms of
      this Trust Agreement, or to question any action of the Trustee or to see
      that any action of the Trustee is authorized by the terms of this Trust
      Agreement.

            (h)   The Trustee shall follow directions of the Committee
      concerning the exercise or non-exercise of any powers or options
      concerning any Contract held in the Trust Fund. Notwithstanding any other
      provision of this Trust Agreement to the contrary, the Company hereby
      agrees to indemnify the Trustee and hold it harmless from and against any
      claim or liability which may be asserted against the Trustee by reason of
      its acting on any direction from the Committee or failing to act in the
      absence of any such direction with respect to any Contract or the
      acquisition of any Contract or exercise of any right or option thereunder.

      4.4   Voting of Securities: The Committee or its agent authorized to act
for the Committee pursuant to Section 5.2 herein shall have the power in its
discretion to exercise all voting rights with respect to any investment held in
the Trust Fund and to grant proxies, discretionary or otherwise, with respect
thereto, except that (a) at any time when an Investment Manager shall be acting
as provided in Section 4.2, the Investment Manager shall exercise its discretion
with respect to voting any securities under its management and shall exercise
all voting rights with respect thereto, (b) the Committee, as provided in
Section 4.1, shall have the sole responsibility with respect to the voting of
any Company Stock which has not been allocated to an Investment Manager and (c)
at any time when the securities are loaned as provided in Section 4.1, the
borrower shall have the authority and responsibility to vote securities it has
borrowed.

      4.5   Powers of Trustee: Except as provided elsewhere in this Trust
Agreement, the Trustee shall have the power to:

            (a)   Manage, sell, contract to sell, grant options to purchase,
      convey, exchange, transfer, abandon, improve, repair, insure, lease for
      any term even though commencing in the future or extending beyond the term
      of the Trust, and otherwise deal with all property, real or personal, in
      such manner, for such considerations and on such terms and conditions as
      the Trustee decides;

            (b)   Participate in any plan of reorganization, consolidation,
      merger, combination, liquidation or other similar plan relating to any
      property held in the Trust Fund, and to consent to or oppose any such plan
      or any action thereunder, or any contract, lease, mortgage, purchase, sale
      or other action by any person or corporation;

            (c)   Deposit any property with any protective, reorganization or
      similar committee; and to pay and agree to pay part of the expenses and
      compensation of any such committee and any assessments levied with respect
      to any property so deposited;

            (d)   Exercise conversion and subscription rights pertaining to any
      property held in the Trust Fund;

                                       15
<PAGE>

            (e)   Extend the time of payment of any obligation held in the Trust
      Fund;

            (f)   Enter into stand-by agreements for future investment, either
      with or without a stand-by fee;

            (g)   Temporarily, hold any part of the assets in cash, without
      liability for interest, pending investment thereof or the payment of
      expenses or making of distributions therewith, notwithstanding the
      Trustee's receipt of "float" from such uninvested cash;

            (h)   Invest in any type of deposit of the Trustee (or of a bank
      related to the Trustee within the meaning of Code Section 414(b)) at a
      reasonable rate of interest or in a common trust fund, as described in
      Code Section 584, or in a collective investment fund, the provisions of
      which govern the investment of such assets and which the Plan incorporates
      by this reference, which the Trustee (or its affiliate as defined in Code
      Section 1504) maintains exclusively for the collective investment of money
      contributed by the bank (or the affiliate) in its capacity as trustee and
      which conforms to the rules of the Comptroller of the Currency;

            (i)   For the purposes of the Trust and with the prior approval of
      the Committee, to borrow money from others, to issue its promissory note
      or notes therefor, and to secure the repayment thereof by pledging any
      property in its possession; provided, however, that the amount or amounts
      of such loans shall not exceed in the aggregate 10% of the market value of
      the Trust Fund as of the date of the borrowing, and further provided that
      no such loan or advance shall be made by the Trustee hereunder other than
      temporary advances to the Trust Fund, on a cash or overdraft basis, on
      which no interest is payable; and

            (j)   If an Investment Manager directing investment under Section
      4.2 is a bank, as defined in the Investment Advisers Act of 1940, to
      transfer to such Investment Manager all or any specified assets in that
      part of the Trust Fund which is subject to such Investment Manager's
      direction, for investment by such Investment Manager through the medium of
      any common, collective, commingled or group trust fund maintained by it
      which consists solely of assets of trusts qualified under Code Section
      401(a) and which is exempt from tax under Code Section 501(a), whereupon
      the instrument establishing such common, collective, commingled or group
      trust fund, as amended from time to time, shall constitute a part of the
      Plan the assets of which are included in such part of the trust fund as
      long as any portion of such assets shall be invested through the medium of
      such common, collective, commingled or group trust fund.

            (k)   Notwithstanding any provision of this Article IV to the
      contrary, the Committee may authorize the Trustee to exercise in its sole
      discretion the powers relating to the lending of securities (and such
      other powers as may be incidental thereto) with respect to securities or
      other property held in the Trust Fund and designated to be subject to the
      discretion of the Trustee or an Investment Manager as otherwise provided
      hereunder ("Subject Account"). If the Subject Account is otherwise subject
      to the discretion of an Investment Manager, such Investment Manager shall
      retain investment

                                       16
<PAGE>

      authority over such account other than the exercise or direction of the
      powers relating to the lending of securities vested in the Trustee, and,
      subject to the requirements of ERISA, shall not be responsible for any act
      or omission of the Trustee.

            (l)   The Trustee shall have the power in its discretion:

                  (i)   To cause any investment to be registered and held in its
            own name, in the name of a nominee, in the name of a nominee of any
            system for the centralized handling of securities, or in book-entry
            or bearer form (provided, however, that the Trustee's books and
            records shall at all times show that all such investments are a part
            of the Trust Fund);

                  (ii)  To collect and receive any and all money and other
            property due to the Trust Fund and to give full discharge therefor;

                  (iii) To settle, compromise or submit to arbitration any
            claims, debts or damages due or owing to or from the Trust; to
            commence or defend suits or legal proceedings to protect any
            interest of the Trust; and to represent the Trust in all suits or
            legal proceedings in any court or before any other body or tribunal;

                  (iv)  To organize under the laws of any state a corporation
            for the purpose of acquiring and holding title to any property which
            it is authorized to acquire under this Trust Agreement and to
            exercise with respect thereto any or all of the powers set forth in
            this Trust Agreement;

                  (v)   To manage, operate, repair, improve, develop, preserve,
            mortgage or lease for any period any real property or any oil,
            mineral or gas properties, royalties, interests or rights held by it
            directly or through any corporation, either alone or by joining with
            others, using other Trust assets for any of such purposes; to
            modify, extend, renew, waive or otherwise adjust any or all of the
            provisions of any such mortgage or lease; and to make provision for
            amortization of the investment in or depreciation of the value of
            such property; and

                  (vi)  Generally to do all acts, whether or not expressly
            authorized, which the Trustee may deem necessary or desirable for
            the protection of the Trust Fund.

      4.6   Payments and Distributions from Trust Fund: The Trustee shall make
such payments and distributions from the Trust Fund at such time or times and to
such person or persons, including a paying agent or agents designated by the
Committee as paying agent as the Committee shall direct in writing; provided,
however, (i) that disbursements for ordinary transaction costs associated with
effecting the investment of transactions of the Trust Fund need not be
authorized by the Committee and (ii) that no payment or distribution in respect
of the Plan shall exceed the value of the Plan in the Trust Fund on the date
such payment or distribution is made. Any cash or property so paid or delivered
to any such paying agent shall be held in trust by such payee until disbursed in
accordance with the Plan. Any written direction of the Committee shall
constitute a certification that the distribution or payment so directed is one
which the Committee is authorized to direct. The Trustee shall have no
responsibility to

                                       17
<PAGE>

ascertain whether any direction received by the Trustee from the Committee or
its designee in accordance with this paragraph is proper and in compliance with
the terms of the Plan.

            The Trustee may make any distribution or payment required to be made
by it hereunder by mailing its check for the specified amount, or delivering the
specified property, to the person to whom such distribution or payment is to be
made, at such address as may have been last furnished to the Trustee, or, if no
such address shall have been so furnished, to such person in care of the Company
or the Committee or if so directed by the Committee by crediting the account of
such person or by transferring funds to such person's account by bank wire or
transfer. If a payment or distribution from the Trust is not claimed, the
Trustee shall promptly notify the Committee thereof and thereafter handle such
payment in accordance with the subsequent direction of the Committee.

            In the event that the Trustee is negligent in making any
distribution or payment hereunder and such negligence results in the making of
such distribution or payment in excess of the amount instructed by the
Committee, it shall be the duty and the responsibility of the Trustee to pursue
any action or proceeding necessary, including the payment of all attorney fees
and related fees and expenses, to recover any such excess amounts. If the
Trustee fails to recover such amounts, the Trustee shall be solely responsible
for the reimbursement of the Trust Fund for such amounts to include reasonable
interest thereon.

      4.7   Trustee's Dealings with Third Parties: Any corporation, transfer
agent or other third party dealing with the Trustee shall not make, nor be
required by any person to make, any inquiry whether the Trustee has authority to
take or omit any action under this Trust Agreement or whether the Committee has
instructed the Trustee to take or omit any such action, but shall be fully
protected in relying upon the certificate of the Trustee that it has authority
to take or omit such proposed action. The seal of the Trustee affixed to any
instrument executed by it shall constitute the Trustee's certificate that it is
authorized as Trustee hereunder to execute such instrument and proceed as may be
provided for therein. No third party shall be required to follow the application
by the Trustee of any money or property which may be paid or transferred to it.

      4.8   Ancillary Trustee: If at any time the Trust Fund shall consist in
whole or in part of assets located in a jurisdiction in which the Trustee is not
authorized to act, the Trustee may appoint an individual or corporation in such
jurisdiction as ancillary trustee and may confer upon such ancillary trustee,
power to act solely with reference to such assets, and such ancillary trustee
shall remit all net income or proceeds from the sale of such assets to the
Trustee. The Trustee may pay such ancillary trustee reasonable compensation and
may absolve it from any requirement that it furnish bond or other security
unless otherwise required by law.

                                       18
<PAGE>

                                   ARTICLE V

                        FOR THE PROTECTION OF THE TRUSTEE

      5.1   Composition of Committee : The Plan shall be administered by the
Committee appointed by the General Partner pursuant to the provisions of the
Plan, and the Trustee shall not be responsible in any respect for such
administration. The Company shall indemnify and hold harmless each member of the
Committee from any and all claims, losses, damages, expenses (including counsel
fees approved by the Committee), and liabilities (including any amounts paid in
settlement with the Committee's approval but excluding any excise tax assessed
against any member or members of the Committee pursuant to the provisions of
Code Section 4975) arising from any act or omission of such member in connection
with his duties and responsibilities under this Trust Agreement, except when the
same is judicially determined to be due to the gross negligence and willful
misconduct of such member. The foregoing right of indemnification shall be in
addition to any rights to which any member of the Committee may otherwise be
entitled as a matter of law. When any member of the Committee shall cease to
act, the General Partner shall promptly give written notice to that effect to
the Trustee, but until such notice is received by the Trustee it shall be fully
protected in continuing to rely upon the authority of such persons. If the full
number of members of the Committee, as provided under the Plan, shall not at any
time have been designated, the remaining member or members acting at such time
shall be deemed to have all of the powers and duties of the Committee; or, if at
any time there is no member of the Committee, the General Partner shall be
deemed to be the Committee.

      5.2   Evidence of Action by Company or Committee: The Committee shall
certify to the Trustee the name or names of any person or persons authorized to
act for the Committee. Until the Committee notifies the Trustee that any such
person is no longer authorized to act for the Committee, the Trustee may
continue to rely on the authority of such person. The Trustee may rely upon any
certificate, notice or direction purporting to have been signed on behalf of the
Committee which the Trustee believes to have been signed by the Committee or the
person or persons authorized to act for the Committee.

            Any action required by any provision of this Trust to be taken by
the General Partner shall be by resolution of the General Partner or by the
written direction of one or more of its president, chief executive officer, any
executive vice president, any vice president, chief financial officer, treasurer
or assistant treasurer, or by such other person or persons as shall be
authorized by such officers or by resolution of the General Partner, which
resolution shall be filed with the Trustee. The Trustee may take or omit to take
any action in accordance with written direction purporting to be signed by such
an officer of the General Partner or other authorized person, or in reliance
upon a certified copy of a resolution of the General Partner which the Trustee
believes to be genuine. The Trustee shall be fully protected in acting in
accordance with such resolution or written direction. Unless other evidence with
respect thereto has been expressly prescribed in this Trust Agreement, any other
action of the Company or of an Affiliate under any provision of this Trust
Agreement, including any approval of, or exceptions to the Trustee's accounts,
shall be evidenced by a certificate signed by an officer of the General Partner
or of an Affiliate, as the case may be, and the Trustee shall be fully protected
in relying upon such certificate.

                                       19
<PAGE>

Any action by the Trustee pursuant to any of the provisions of this Trust
Agreement shall be sufficiently evidenced by a certification of one of its Vice
Presidents, Assistant Vice Presidents or other appropriate Trust Officers, and
the General Partner, each Affiliate which participates in the Trust, the
Committee and all other persons in interest may rely upon, and shall be fully
protected in acting in accordance with, such certification.

      5.3   Communications: Communications to the Trustee shall be addressed to
it at 50 LaSalle Street, Chicago, Illinois, 60675. Communications to the
Committee, the Company or any Affiliate shall be addressed to it at 1111
Louisiana, Houston, Texas 77002, with a copy to the Committee, Attention:
Secretary, P.O. Box 61867, Houston, Texas 77208, unless the Trustee, the
Committee, the Company or any Affiliate, respectively, shall request that
communications be sent to another address. No communication shall be binding
upon the Trust Fund or the Trustee, or upon the Committee, the Company or any
Affiliate until it is received by the Trustee, the Committee, the Company or the
appropriate Affiliate, as the case may be.

      5.4   Advice of Counsel : The Trustee may consult with any legal counsel,
including counsel to the Company or the Committee, with respect to the
construction of this Trust Agreement, its duties hereunder, or any act which it
proposes to take or omit.

      5.5   Miscellaneous: The Trustee shall discharge its duties hereunder with
the care, skill, prudence and diligence under the circumstances then prevailing
that a prudent man acting in a like capacity and familiar with such matters
would use in the conduct of an enterprise of a like character and with like
aims. The Trustee, to the extent that it has investment discretion, shall not be
liable for any loss sustained by the Trust Fund by reason of the purchase,
retention, sale or exchange of any investment in good faith and in accordance
with the provisions of this Trust Agreement and of any applicable Federal law.

            The Trustee's duties and obligations shall be limited to those
expressly imposed upon it by this Trust, notwithstanding any reference to the
Plan.

            The Company, any Affiliate, the Committee or all of them, at any
time may employ as agent (to perform any act, keep any records or accounts, or
make any computations required of the Company, an Affiliate, or the Committee by
this Trust Agreement or the Plan) the corporation serving as Trustee hereunder.
Nothing done by said corporation as such agent shall affect its responsibility
or liability as Trustee hereunder.

      5.6   Fiduciary Responsibilities: The Trustee, the Investment Managers, if
any, and the members of the Committee shall discharge their duties with respect
to the Trust solely in the interest of the participants in the Plan and their
beneficiaries and with the care, skill, prudence, and diligence under the
circumstances then prevailing that a prudent man acting in a like capacity and
familiar with such matters would use in the conduct of an enterprise of a like
character and with like aims.

            No "fiduciary" (as such term is defined in Section 3(21) of ERISA,
or any successor statutory provision) under this Trust Agreement shall be liable
for an act or omission of another person in carrying out any fiduciary
responsibility where such fiduciary responsibility

                                       20
<PAGE>

is allocated to such other person by this Trust Agreement or pursuant to a
procedure established in this Trust Agreement except to the extent that:

                  (i)   such fiduciary participated knowingly in, or knowingly
            undertook to conceal, an act or omission of such other person,
            knowing such act or omission to be a breach of fiduciary
            responsibility;

                  (ii)  such fiduciary, by his failure to comply with Section
            404(a)(1) of ERISA (or any successor statutory provision) in the
            administration of his specific responsibilities which give rise to
            his status as a fiduciary, has enabled such other person to commit a
            breach of fiduciary responsibility;

                  (iii) such fiduciary has knowledge of a breach of fiduciary
            responsibility by such other person, unless he makes reasonable
            efforts under the circumstances to remedy the breach; or

                  (iv)  such fiduciary is a "named fiduciary" (as such term is
            defined in Section 402(a)(2) of ERISA, or any successor statutory
            provision) and has violated his duties under Section 404(a)(1) of
            ERISA (or any successor statutory provision):

                        (a)   with respect to the allocation of fiduciary
                  responsibilities among named fiduciaries or the designation of
                  persons other than named fiduciaries to carry out fiduciary
                  responsibilities under this Trust Agreement;

                        (b)   with respect to the establishment or
                  implementation of procedures for allocating fiduciary
                  responsibilities among named fiduciaries or for designating
                  persons other than named fiduciaries to carry out fiduciary
                  responsibilities under this Trust Agreement; or

                        (c)   in continuing the allocation of fiduciary
                  responsibilities among named fiduciaries or the designation of
                  persons other than named fiduciaries to carry out fiduciary
                  responsibilities under this Trust Agreement.

            In the event that the Company incurs any liability, loss, claim,
suit or expense (including reasonable attorneys' fees) in connection with or
arising out of the negligent, intentionally tortious, fraudulent or criminal act
of the Trustee in carrying out its responsibilities under this Trust Agreement,
the Trustee shall indemnify and hold the Company harmless from and against any
such direct liability, loss, claim, suit or expense. Notwithstanding the above,
nothing contained in this paragraph shall limit the Trustee's right to
indemnification under Section 4.2(c) of this Trust Agreement or require the
Trustee to indemnify the Company for any action or inaction pursuant to Section
4.2(c) of this Trust Agreement.

                                       21
<PAGE>

                                   ARTICLE VI

                   TAXES, EXPENSES AND COMPENSATION OF TRUSTEE

      6.1   Taxes and Expenses: Brokerage fees, commissions, stock transfer
taxes and other charges and expenses incurred in connection with the purchase
and sale of securities for the Trust Fund or distribution thereof shall be paid
by the Trustee from the Trust Fund. All taxes imposed or levied with respect to
the Trust Fund or any part thereof, under existing or future laws, shall be paid
from the Trust Fund. The Trustee shall pay from the Trust Fund, to the extent
not paid by the Company and/or the Affiliates which participate in the Plan, its
reasonable expenses of management and administration of the Trust, including
reasonable compensation of counsel and any agents engaged by the Trustee to
assist it in such management and administration, the fees of any Investment
Manager and any specified expenses of administration of the Plan including, but
not limited to, audit fees, investment consulting fees, and actuarial and
recordkeeping expenses.

      6.2   Compensation of the Trustee: The Trustee shall receive for its
services as Trustee hereunder such reasonable compensation which may be agreed
upon from time to time by the Company and the Trustee. All amounts due the
Trustee as compensation for its services shall be paid by the Company, or
prorated among the Company and the Affiliates which participate in this Trust in
such a manner as they deem equitable, or disbursed by the Trustee out of the
Trust Fund, and, until paid, shall constitute a charge upon the Trust Fund.

                                       22
<PAGE>

                                  ARTICLE VII

                             SETTLEMENT OF ACCOUNTS;
                     DETERMINATION OF INTERESTS UNDER TRUST

      7.1   Settlement of Accounts of Trustee: The Trustee shall keep accurate
and detailed accounts of all of its receipts, investments and disbursements
under this Trust Agreement on a modified cash basis. The financial statements,
books and records of the Trustee with respect to the Trust shall be open to
inspection during business hours of the Trustee by the Company or the Committee
or their representatives, including, without limitation, independent certified
public accountants engaged by the Company or the Committee, on behalf of all
participants in the Plan, to permit compliance with the reporting and disclosure
requirements of ERISA. However, such financial statements, books and records may
not be audited more frequently than twice in each fiscal year. If an examination
of the financial statements of the Plan requires a review of the underlying
transactions affecting such financial statements, such independent certified
public accountants shall rely on the report of the independent certified public
accountants engaged by the Trustee to review its procedures and controls, to the
extent such reliance is permitted by generally accepted auditing standards.

            Within 90 days after the close of each calendar year, or any
termination of the duties of the Trustee, the Trustee shall prepare, sign and
mail in duplicate to the Company and the Committee an account of its acts and
transactions as Trustee hereunder. Such account shall include a statement of the
value of the Trust Fund as of the last day of such year or other period and a
statement of the portion of the Trust Fund under management by any Investment
Manager as of the same date. If the Company finds the account to be correct, the
Company shall sign the instrument of settlement and return such statement to the
Trustee, whereupon the account shall become an account stated. If within 90 days
after receipt of the account or any amended account the Company has not signed
and returned an instrument of settlement to the Trustee, nor filed with the
Trustee notice of any objection to any act or transaction of the Trustee, the
account or amended account shall become an account stated. If any objection has
been filed, and if the Company is satisfied that it should be withdrawn or if
the account is adjusted to its satisfaction, the Company shall in writing filed
with the Trustee signify its approval of the account and it shall become an
account stated. In each case in which an account becomes an account stated, the
account shall be an account stated between the Trustee and the Company and any
Affiliate which has adopted the Plan.

            When an account becomes an account stated, such account shall be
finally settled, and the Trustee shall be completely discharged and released, as
if such account had been settled and allowed by a judgment or decree of a court
of competent jurisdiction in an action or proceeding in which the Trustee, the
Company and any Affiliate which has adopted the Plan were parties.

            The account of the Trustee's acts and transactions delivered to the
Committee shall be settled, and shall become an account stated, in the same
manner as the account delivered to the Company hereunder. When an account
becomes an account stated as between the Trustee and the Committee, the account
shall be finally settled and the Trustee shall be completely discharged and
released, as if such account had been settled and allowed by a judgment or
decree

                                       23
<PAGE>

of a court of competent jurisdiction in an action or proceeding in which the
Trustee and the Committee were parties.

            The Trustee, the Committee or the Company shall have the right to
apply at any time to a court of competent jurisdiction for judicial settlement
of any account of the Trustee not previously settled as hereinabove provided. In
any such action or proceeding it shall be necessary to join as parties only the
Trustee, the Committee and the Company (although the Trustee may also join such
other parties as it may deem appropriate), and any judgment or decree entered
therein shall be conclusive.

      7.2   Determination of Rights and Benefits of Persons Claiming an Interest
in the Trust Fund; Enforcement of Trust Fund: The Committee shall have authority
to determine the existence, non-existence, nature and amount of the rights and
interests of all persons under the Plan and in or to the Trust Fund, and the
Trustee shall have no power, authority, or duty in respect of such matters, or
to question or examine any determination made by the Committee, or any direction
given by the Committee to the Trustee. The Company, other employers and the
Committee shall have authority, either jointly or severally, to enforce this
Trust Agreement on behalf of any and all persons having or claiming any interest
in the Trust Fund or under this Trust Agreement or the Plan.

                                       24
<PAGE>

                                  ARTICLE VIII

              RESIGNATION, REMOVAL AND SUBSTITUTION OF THE TRUSTEE

      8.1   Resignation of Trustee: The Trustee may resign its duties hereunder
by filing with the Committee its written resignation. No such resignation shall
take effect until 60 days from the date thereof unless shorter notice is
acceptable to the Committee.

      8.2   Removal of Trustee: The Trustee may be removed by the General
Partner at any time upon not less than 60 days notice to the Trustee, but such
notice may be waived by the Trustee. Such removal shall be effected by
delivering to the Trustee a written notice of its removal executed by the
Company, and by giving notice to the Trustee of the appointment of a successor
Trustee in the manner hereinafter set forth.

      8.3   Appointment of Successor Trustee: The appointment of a successor
Trustee hereunder shall be accomplished by and shall take effect upon the
delivery to the resigning or removed Trustee, as the case may be, of (a) an
instrument in writing appointing such successor Trustee, executed by the
Company, together with a certified copy of the resolution of the General Partner
to such effect and (b) an acceptance in writing of the office of successor
Trustee hereunder executed by the successor so appointed, both of which
documents shall be acknowledged in like manner as this Trust Agreement. The
Company shall send notice of such appointment to each Affiliate participating in
the Plan, and to each member of the Committee then in office. Any successor
Trustee hereunder may be either a corporation authorized and empowered to
exercise trust powers or one or more individuals. All of the provisions set
forth herein with respect to the Trustee shall relate to each successor Trustee
so appointed with the same force and effect as if such successor Trustee had
been originally named herein as the Trustee hereunder. If within 60 days after
notice of resignation shall have been given under the provisions of this Article
VIII a successor Trustee shall not have been appointed, the resigning Trustee or
any member of the Committee may apply to any court of competent jurisdiction for
the appointment of a successor Trustee.

      8.4   Transfer of Trust Fund to Successor: Upon the appointment of a
successor Trustee, the resigning or removed Trustee shall transfer and deliver
the Trust Fund and the records relating thereto to such successor Trustee, after
reserving such reasonable amount as it shall deem necessary to provide for its
expenses in the settlement of its accounts, the amount of any compensation due
it and any sums chargeable against the Trust Fund for which it may be liable,
but if the sums so reserved are not sufficient for such purposes, the resigning
or removed Trustee shall be entitled to reimbursement for any deficiency from
the successor Trustee and from the Company and each Affiliate participating in
the Plan, who shall be jointly and severally liable therefor.

                                       25
<PAGE>

                                   ARTICLE IX

                  DURATION AND TERMINATION OF TRUST; AMENDMENT

      9.1   Duration and Termination: This Trust Agreement shall continue for
such time as may be necessary to accomplish the purpose for which it was created
but may be terminated at any time by the General Partner. Notice of such
termination shall be given to the Trustee by an instrument in writing executed
by the Company and acknowledged in the same form as this Trust Agreement,
together with a certified copy of the resolution of the General Partner
authorizing such termination. The Company shall notify the Committee and each
Affiliate of such termination.

      9.2   Distribution Upon Termination: If this Trust Agreement is
terminated, the Trustee upon the written direction of the Committee shall
liquidate the Trust Fund to the extent required for distribution and, after its
final account has been settled as provided in Article VII, shall distribute the
net balance thereof to such person or persons, at such time or times and in such
proportions and manner as may be directed by the Committee, or in the absence of
such direction, as may be directed by a judgment or decree of a court of
competent jurisdiction. Upon making such distributions, the Trustee shall be
relieved from all further responsibility. The powers of the Trustee hereunder
shall continue so long as any assets of the Trust Fund remain in its hands.
Notwithstanding the foregoing provisions of this Section 9.2, the Company may
promptly advise the appropriate District Director of Internal Revenue of the
termination of the Trust and the Trustee may delay the final distribution to
Participants in the terminated Plan until said District Director shall advise in
writing that such termination does not adversely affect the previously qualified
status of the terminated Plan or the exemption from tax of the Trust under Code
Section 401(a) or 501(a).

      9.3   Certain Withdrawals: Each Affiliate which participates in the Trust
shall have the right to withdraw from this Trust upon six months' written notice
to the Trustee and the Committee, which written notice may be waived by the
Trustee and the Committee. In the event that any Affiliate which participates in
the Trust shall cease to be an Affiliate of the Company, such corporation shall
withdraw from this Trust as soon as arrangements may be reasonably made
therefor, but in any event such withdrawal shall be made not more than six
months after the date such corporation ceases to be an Affiliate. Upon such
withdrawal, the Committee shall certify to the Trustee the interest in the Trust
Fund of the participants of such withdrawing corporation and the Trustee shall
thereupon separate such interest from the Trust Fund as provided below in this
Section. The Committee may at any time direct the Trustee to segregate and
withdraw any portion as may be certified to the Trustee by the Committee as
allocable to any specified group or groups of employees or beneficiaries.
Whenever segregation is required, the Trustee shall withdraw from the Trust Fund
such assets as it shall in its absolute discretion deem to be equal in value to
the equitable share to be segregated. Such withdrawal from the Trust Fund shall
be in cash or in any property held in such Fund, or in a combination of both, in
the direction of the Committee. The Trustee shall thereafter hold the assets so
withdrawn as a separate trust fund in accordance with the provisions either of
this Trust Agreement (which shall be construed in respect of such assets as if
the employer participating in the Plan (determined without regard to whether any
subsidiaries or affiliates of such employer have joined in the

                                       26
<PAGE>

Plan)) had been named as the Company hereunder or of a separate trust agreement.
Such segregation shall not preclude later readmission to the Trust.

      9.4   Amendment: By an instrument in writing delivered to the Trustee
executed pursuant to the order of the General Partner and acknowledged in the
same form as this Trust Agreement, the Company shall have the right at any time
and from time to time to amend this Trust Agreement in whole or in part except
that the duties and responsibilities of the Trustee shall not be increased
without the Trustee's written consent; provided, however, that no such amendment
shall authorize or permit, at any time prior to the satisfaction of all
liabilities with respect to employees and their beneficiaries under the Plan,
any part of the Trust Fund to be used for, or diverted to, any purposes other
than for the exclusive benefit of such employees and their beneficiaries.
Notwithstanding the foregoing, the Committee may authorize any amendment or
modification to Article IV of this Trust Agreement regarding the selection of
investment advisors or investment options in which the Trust Fund may be
invested including, without limitation, the Group Trusts.

            Any such amendment shall become effective upon (a) delivery to the
Trustee of the written instrument of amendment executed by the appropriate
officers of the Company, together with a certified copy of the resolution of the
General Partner authorizing such amendment and (b) endorsement by the Trustee on
such instrument of its receipt thereof, together with its consent thereto if
such consent is required.

                                       27
<PAGE>

                                   ARTICLE X

                                  MISCELLANEOUS

      10.1  Governing Law; No Bond Required of Trustee: Subject to the
provisions of ERISA, as they may be amended from time to time, which may be
applicable and provide to the contrary, this Trust Agreement and the Trust
hereby created shall be governed, construed, administered and regulated in all
respects under the laws of the State of Texas. No bond or other security for the
faithful performance of its duties hereunder shall be required of the Trustee
unless otherwise required by law.

      10.2  Interest in Trust Fund; Assignment: No document shall be issued
evidencing any interest in the Trust or in the Trust Fund, and no Affiliate
shall have the power to assign all or any part of its equitable share of the
Trust Fund or of its interest therein.

      10.3  Invalid Provisions: If any provision or provisions of this Trust
Agreement shall be held illegal or invalid for any reason, said illegality or
invalidity shall not affect the remaining provisions of this Trust Agreement,
but shall be fully severable and the Trust Agreement shall be construed and
enforced as if said illegal or invalid provisions had never been inserted
herein.

      10.4  Remedies: If a dispute arises between the Company and the Trustee,
such dispute shall be settled by agreement between the parties. In the absence
of an acceptable agreement resolving the dispute, such dispute shall be
submitted to a court of competent jurisdiction for judicial settlement thereof.

      10.5  Prohibition of Diversion: Except as provided in Article VI hereof,
it shall be impossible under this Trust Agreement for any part of the corpus or
income of the Trust Fund to be used for, or diverted to, purposes other than for
the exclusive benefit of employees of the Company and Affiliates Participating
in the Plan and the beneficiaries of such employees. It shall also be impossible
under this Trust Agreement for any part of the Trust Fund to revert directly or
indirectly to the Company or any Affiliate participating in the Plan, except to
the extent such reversions are specifically authorized under Section 403(c)(2)
of ERISA.

      10.6  Headings for Convenience Only: The headings and subheadings in this
Trust Agreement are inserted for convenience of reference only and are not to be
used in construing this instrument or any provision thereof.

      10.7  Successors and Assigns: This Trust Agreement shall bind and inure to
the benefit of the successors and assigns of the Company and the Trustee,
respectively.

                                       28
<PAGE>

            IN WITNESS WHEREOF, the General Partner and Trustee have caused
these presents to be executed by their duly authorized officers, in a number of
copies all of which shall constitute one and the same instrument which may be
sufficiently evidenced by any executed copy hereof, this 26th day of August,
2004, but effective as of September 1, 2004.

                                             TEXAS GENCO GP, LLC,

                                             GENERAL PARTNER OF TEXAS GENCO, LP

                                             By  /s/ DAVID G. TEES
                                               ---------------------------------
                                             Name:   David G. Tees
                                             Title:  President and CEO
ATTEST:

/s/ RICHARD DAUPHIN
--------------------------
Assistant Secretary

                                             THE NORTHERN TRUST COMPANY, TRUSTEE

                                             By /s/ JOHN J. MALUSA
                                               ---------------------------------
                                             Name:  John J. Malusa
                                             Title: Vice President


ATTEST:

/s/ PHIL MICHELE
--------------------------

                                       29