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                                                                    Exhibit 10.1













                            ATMOS ENERGY CORPORATION

                             PERFORMANCE-BASED SEBP

                                 TRUST AGREEMENT



                        EFFECTIVE AS OF DECEMBER 1, 2000




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                                TABLE OF CONTENTS

                                                                            PAGE


ARTICLE I      DEFINITIONS                                                   2

ARTICLE II     ESTABLISHMENT OF TRUST                                        4

ARTICLE III    PAYMENTS TO PLAN PARTICIPANTS AND THEIR
               BENEFICIARIES                                                 5

ARTICLE IV     TRUSTEE RESPONSIBILITY REGARDING PAYMENTS TO
               TRUST BENEFICIARY WHEN COMPANY IS INSOLVENT                   6

ARTICLE V      PAYMENTS TO COMPANY                                           8

ARTICLE VI     THE RIGHTS OF THE PARTICIPANTS AND CREDITORS
               TO THE TRUST ESTATE                                           8

ARTICLE VII    INVESTMENT AUTHORITY                                          9

ARTICLE VIII   DUTIES, POWERS AND RESPONSIBILITIES OF TRUSTEE
               AND ASSET MANAGERS                                           10

ARTICLE IX     INDEMNIFICATION; LIABILITIES OF THE TRUSTEE                  15

ARTICLE X      TRUSTEE'S COMPENSATION AND EXPENSES                          16

ARTICLE XI     TAXES                                                        16

ARTICLE XII    RESIGNATION AND REMOVAL OF TRUSTEE;
               APPOINTMENT OF SUCCESSOR                                     16

ARTICLE XIII   AMENDMENT OR TERMINATION                                     17

ARTICLE XIV    MISCELLANEOUS                                                18

ARTICLE XV     EFFECTIVE DATE                                               19



                                        i
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                            ATMOS ENERGY CORPORATION

                             PERFORMANCE-BASED SEBP

                                 TRUST AGREEMENT


     THIS ATMOS ENERGY CORPORATION PERFORMANCE-BASED SEBP TRUST AGREEMENT (the
"Trust Agreement") is made this 1st day of December, 2000, between Atmos Energy
Corporation (the "Company"), as Settlor, and Bankers Trust Company, as Trustee,
for the benefit of such employees of the Company as are participants in the Plan
(as defined in Section 1.6 herein) from time to time to provide funds to satisfy
the obligations of the Company to participants under the Plan.

     WHEREAS, Company has adopted the Atmos Energy Corporation Performance-Based
Supplemental Executive Benefits Plan.

     WHEREAS, Company has incurred or expects to incur liability under the terms
of such Plan with respect to the individuals participating in such Plan for
monthly supplemental retirement income and disability benefits and/or death
benefits (the "Supplemental Benefits" or "Benefits");

     WHEREAS, Company wishes to establish a trust (hereinafter called "Trust")
and to contribute to the Trust assets that shall be held therein, subject to the
claims of Company's creditors in the event of Company's Insolvency (as herein
defined) until paid to Plan participants and their beneficiaries in such manner
and at such times as specified in the Plan;

     WHEREAS, it is the intention of the parties that this Trust shall
constitute an unfunded arrangement and shall not affect the status of the Plan
as an unfunded plan maintained for the purpose of providing deferred
compensation for a select group of management or highly compensated employees
for purposes of Title I of the Employee Retirement Income Security Act of 1974;

     WHEREAS, it is the intention of Company to make contributions to the Trust
to provide itself with a source of funds to assist it in the meeting of its
liabilities under the Plan;

     WHEREAS, Bankers Trust Company is willing to act as Trustee of the Trust
upon all of the terms and conditions hereinafter set forth;

     NOW, THEREFORE, the parties do hereby establish the Trust and agree that
the Trust shall be comprised, held and disposed of as follows:



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                                    ARTICLE I

                                   DEFINITIONS

     1.1 "Asset Manager" shall mean, individually or collectively as the context
shall require, the Trustee, with respect to those assets of the Trust allocated
to the Discretionary Fund, or an Investment Manager or the Company with respect
to those assets of the Trust allocated to a Directed Fund to the extent each is
authorized to exercise, discretionary investment authority or control over such
assets under Section 7.1.

     1.2 (a) "Change in Control" of the Company shall be deemed to have occurred
if:

              (i) any "Person" (as defined in 1.2(b)(i) below), other than (1)
         the Company or any of its subsidiaries, (2) a trustee or other
         fiduciary holding securities under an employee benefit plan of the
         Company or any of its Affiliates, (3) an underwriter temporarily
         holding securities pursuant to an offering of such securities, or (4) a
         corporation owned, directly or indirectly, by the shareholders of the
         Company in substantially the same proportions as their ownership of
         stock of the Company, is or becomes the "beneficial owner" (as defined
         in Section 1.2(b)(ii) below), directly or indirectly, of securities of
         the Company (not including in the securities beneficially owned by such
         person any securities acquired directly from the Company or its
         Affiliates) representing 33-1/3% or more of the combined voting power
         of the Company's then outstanding securities, or 33-1/3% or more of the
         then outstanding common stock of the Company, excluding any Person who
         becomes such a beneficial owner in connection with a transaction
         described in subparagraph (iii)(A) below.

              (ii) During any period of two consecutive years (the "Period"),
         individuals who at the beginning of the Period constitute the Board of
         Directors of the Company and any "new director" (as defined in Section
         1.2(b)(iii) below) cease for any reason to constitute a majority of the
         Board of Directors.

              (iii) There is consummated a merger or consolidation of the
         Company or any direct or indirect subsidiary of the Company with any
         other corporation, except if:

                   (A) the merger or consolidation would result in the voting
              securities of the Company outstanding immediately prior thereto
              continuing to represent (either by remaining outstanding or by
              being converted into voting securities of the surviving entity or
              any parent thereof) at least 60% of the combined voting power of
              the voting securities of the Company or such surviving entity or
              any parent thereof outstanding immediately after such merger or
              consolidation; or

                   (B) the merger or consolidation is effected to implement a
              capitalization of the Company (or similar transaction) in which no
              Person is or becomes the beneficial owner, directly or indirectly,
              of




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              securities of the Company (not including in the securities
              beneficially owned by such Person any securities acquired directly
              from the Company or its Affiliates other than in connection with
              the acquisition by the Company or its Affiliates of a business)
              representing 60% or more of the combined voting power of the
              Company's then outstanding securities.

              (iv) The shareholders of the Company approve a plan of complete
         liquidation or dissolution of the Company or an agreement for the sale
         or disposition by the Company of all or substantially all the Company's
         assets, other than a sale or disposition by the Company of all or
         substantially all of the Company's assets to an entity, at least 60% of
         the combined voting power of the voting securities of which are owned
         by the stockholders of the Company in substantially the same
         proportions as their ownership of the Company immediately prior to such
         sale.

         (b) Definitions. For purposes of Section 1.2(a) above,

              (i) "Person" shall have the meaning given in Section 3(a)(9) of
         the Securities Exchange Act of 1934 as modified (the "1934 Act") and
         used in Sections 13(d) and 14(d) of the 1934 Act.

              (ii) "Beneficial Owner" shall have the meaning provided in Rule
         13d-3 under the 1934 Act.

              (iii) "New Director" shall mean an individual whose election by
         the Company's Board of Directors or nomination for election by the
         Company's shareholders was approved by a vote of at least two-thirds of
         the directors then still in office who either were directors at the
         beginning of the Period or whose election or nomination for election
         was previously so approved or recommended. However, "new director"
         shall not include a director whose initial assumption of office is in
         connection with an actual or threatened election contest, including but
         not limited to a consent solicitation relating to the election of
         directors of the Company.

              (iv) "Affiliate" shall have the meaning set forth in Rule 12b-2
         promulgated under Section 12 of the 1934 Act.

     1.3 "Directed Fund" shall mean each portion of the Trust subject to the
discretionary management and control of an Asset Manager other than the Trustee.
If more than one Directed Fund is established under this Trust Agreement,
"Directed Fund" shall also mean the Directed Fund subject to the management and
control of a particular Asset Manager, as the context may require.

     1.4 "Discretionary Fund" shall mean any portion of the Trust subject to the
discretionary management and control of the Trustee.

     1.5 "Investment Manager" shall mean (i) an investment adviser registered
under the Investment Advisers Act of 1940, (ii) a bank as defined in that Act,
or (iii) an insurance company qualified to manage, acquire or dispose of any
assets of the trusts under the laws of one or more state.



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         1.6 "Plan" shall mean the Atmos Energy Corporation Performance-Based
Supplemental Executive Benefits Plan, as amended from time to time.

         1.7 "Trust" shall mean the Atmos Energy Corporation Performance-Based
SEBP Trust established and continued under this Trust Agreement.

         1.8 "Trustee" shall mean Bankers Trust Company and its successors and
assigns, and any successor trustee of the Trust acting at the time in question.

                                   ARTICLE II

                             ESTABLISHMENT OF TRUST

     2.1 The Company hereby deposits with Trustee in trust One Hundred Dollars
($100.00), which shall become the principal of the Trust, to be held,
administered and disposed of by Trustee as provided in this Trust Agreement.

     2.2 The Trust shall be revocable. Notwithstanding the foregoing, the Trust
shall become irrevocable thirty (30) days following the issuance of a favorable
private letter ruling regarding the Trust from the Internal Revenue Service.

     2.3 The Trust is intended to be a grantor trust, of which Company is a
grantor, within the meaning of subpart E, part I, subchapter J, chapter 1,
subtitle A of the Internal Revenue Code of 1986, as amended (the "Code"), and
shall be construed accordingly. The Company acknowledges that determination of
the status of the Trust as a grantor trust has been made by the Company, and
Trustee assumes no responsibility in this regard.

     2.4 The principal of the Trust, and any earnings thereon shall be held
separate and apart from other funds of the Company and shall be used exclusively
for the uses and purposes of Plan participants and general creditors as herein
set forth. Plan participants and their beneficiaries shall have no preferred
claim on, or any beneficial ownership interest in, any assets of the Trust. Any
rights created under the Plan and this Trust Agreement shall be mere unsecured
contractual rights of Plan participants and their beneficiaries against the
Company. Any assets held by the Trust will be subject to the claims of the
Company's general creditors under federal and state law in the event of
Insolvency, as defined in Section 4.1 herein.

     2.5 The Company shall make such deposits as provided for in the Plan and
may, in its sole discretion, at any time, or from time to time, make additional
deposits of cash or other property acceptable to the Trustee in trust with
Trustee to augment the principal to be held, administered and disposed of by
Trustee as provided in this Trust Agreement. Notwithstanding the foregoing, upon
and after a Change in Control, Trustee shall be responsible for assuring that
deposits are made in accordance with the Plan, and it may rely on written
certifications of the actuary employed with respect to the Plan as to the funded
status of the Trust and the Company's contribution obligations under the Plan.
Prior to a Change in Control, the Trustee shall have no responsibility therefor.



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                                   ARTICLE III

              PAYMENTS TO PLAN PARTICIPANTS AND THEIR BENEFICIARIES

     3.1 The Company shall be solely responsible for keeping accurate books and
records with respect to the Plan participants and beneficiaries, their
compensation and rights and interests in the Trust pursuant to the Plan. As soon
as practicable after the establishment of this Trust or the amendment of the
Plan, the Company shall provide the Trustee with copies of the Plan and any
amendments. The Trustee shall not be required to maintain any separate records
or accounts with respect to any Plan participant or beneficiary, and any records
or accounts required to be maintained pursuant to the terms of the Plan shall be
the responsibility of the Company.

     3.2 Trustee shall make payments of Supplemental Benefits to Plan
participants from the assets of the Trust, if and to the extent such assets are
available for distribution, in accordance with the Plan, at all times the
Company is not Insolvent. Trustee shall not be required to make payments unless
notified by the Company or the Plan participant that Benefits are then due and
owing to the Plan participant, and it has received a written certification of
the time for payment of Benefits and the amount of Benefits due and owing to the
Plan participant at such time, all in accordance with the Plan, prepared by the
actuary employed by the Company to calculate the Supplemental Benefits, and has
received sufficient information that indicates the amount of federal, state
and/or local taxes to be withheld from such payment and the form in which such
amount is to be paid (as provided for or available under the Plan). In addition,
the Trustee shall make provision for the payment and reporting of any federal,
state or local taxes that may be required to be withheld with respect to the
payment of Benefits. The actuary shall also provide written certification to the
Trustee of any changes in the amount of Benefits payable to a Beneficiary from
time to time. Following a Change in Control, if no actuary is employed by the
Company, the Trustee shall employ an actuary. The Trustee shall be fully
protected in relying on the written certification of the actuary for all
purposes of this Agreement.

     3.3 The entitlement of a Plan participant or his or her beneficiaries to
Benefits under the Plan shall be determined by the Company or such party (other
than the Trustee) as the Company shall designate under the Plan, and any claim
for such Benefits shall be considered and reviewed under the procedures set out
in the Plan. Except as set forth in this Trust Agreement, the Trustee shall have
no responsibility with regard to administration of the Plan. Without limiting
the generality of the foregoing, the Trustee shall have no responsibility should
the Trust have insufficient assets from which to make any distribution called
for under the Plan, the Trustee shall have no responsibility to interpret the
provisions of the Plan, and the Trustee shall have no responsibility for
determining whether any Plan participant or their beneficiary has become
entitled to any distribution under the Plan, or the amount thereof, and the
Trustee shall be entitled to rely solely upon the accuracy, timeliness and
completeness of the Benefit information delivered to it by the actuary.

     3.4 The Company may make payment of Supplemental Benefits directly to Plan
participants or their beneficiaries as they become due under the terms of the
Plan. In such event, the Company shall also provide for the reporting,
withholding and payment of any federal, state or local taxes that may be
required to be withheld with respect to such Benefit payments. The Company shall
notify Trustee of its decision to make payment of Benefits directly prior to the
time amounts are payable to participants or their


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beneficiaries. In addition, if the principal of the Trust, and any earnings
thereon, are not sufficient to make payments of Benefits in accordance with the
terms of the Plan, the Company shall make the balance of each such payment as it
falls due. Trustee shall notify the Company where principal and earnings are not
sufficient to pay Benefits as they became due. The Company shall provide the
Trustee with a schedule of all Benefits that have been paid by the Company
directly to Participants and a schedule of all tax withholding payments made by
it to the taxing authorities within fifteen (15) days after the end of the month
in which such payments have been made.

     3.5 The Trustee shall notify the Company periodically of any returned or
undeliverable payments to Plan participants or their beneficiaries. Any payments
remaining unclaimed for six (6) months after such notice has been given to the
Company shall be returned to the Trust.

     3.6 The Trustee shall have sole responsibility with respect to all payments
made from the Trust for the payment of all withholding taxes to, and the filing
of all required tax returns with, the appropriate taxing authority and shall
furnish each Participant with the appropriate tax information form evidencing
such payment and the amount thereof.

     3.7 It is expressly acknowledged that Employee (or if Employee is dead, his
beneficiaries under the Plan) is a third-party beneficiary under this Trust
Agreement and, as such, shall have the right to enforce the terms of this
Agreement as if he were a party hereto.

                                   ARTICLE IV

       TRUSTEE RESPONSIBILITY REGARDING PAYMENTS TO TRUST BENEFICIARY WHEN
                              COMPANY IS INSOLVENT

     4.1 Trustee shall cease payment of Benefits to Plan participants and their
beneficiaries if the Company is Insolvent. The Company shall be considered
"Insolvent" for purposes of this Trust Agreement if (i) the Company is unable to
pay its debts as they become due, or (ii) the Company is subject to a pending
proceeding as a debtor under the United States Bankruptcy Code.

     4.2 At all times during the continuance of this Trust, as provided in
Sections 2.4 and 6.1 hereof, the principal and income of the Trust shall be
subject to claims of general creditors of the Company under federal and state
law as set forth below.

         (a) The Board of Directors and the Chief Executive Officer of the
     Company shall have the duty to inform Trustee in writing of the Company's
     Insolvency. The Company shall also have the duty to respond to any inquiry
     from the Trustee regarding the Company's possible Insolvency, if the
     Trustee has an obligation to determine whether the Company is Insolvent. If
     a person claiming to be a creditor of the Company alleges in writing to the
     Trustee that the Company has become Insolvent, Trustee shall determine
     whether the Company is Insolvent and, pending such determination, Trustee
     shall discontinue payment of Supplemental Benefits to Plan participants or
     their beneficiaries. In determining whether or not the Company is
     Insolvent, Trustee may rely on a written statement signed by the Company,
     together with the evidence supporting such statement that is satisfactory
     to the Trustee, that the Company is not Insolvent, or may await receipt of
     an order




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<PAGE>   9

     from a regulatory agency or court of competent jurisdiction directing
     disposition of the Trust assets.

         (b) Unless Trustee has actual knowledge of the Company's Insolvency, or
     has received notice from the Company or a person claiming to be a creditor
     of the Company alleging that the Company is Insolvent, Trustee shall have
     no duty to inquire whether the Company is Insolvent. Trustee may in all
     events rely on such evidence concerning the Company's solvency as may be
     furnished to Trustee and that provides Trustee with a reasonable basis for
     making a determination concerning the Company's solvency. Specifically, the
     Trustee may rely conclusively upon, and shall be protected in relying upon,
     court records submitted to it showing whether the Company is Insolvent, a
     current report or statement from a nationally recognized credit reporting
     agency submitted to it showing whether such Company is Insolvent, or the
     written notice with supporting evidence where appropriate, submitted to it
     from the Company as provided in this Section 4.2 stating that the Company
     is or is not Insolvent. For purposes of this Trust, knowledge and
     information regarding the Company which is not in the possession of
     employees of the Trustee's Trust Department shall not be imputed to the
     Trustee.

         (c) If at any time the Trustee has determined that the Company is
     Insolvent, Trustee shall discontinue payments to the Company's Plan
     participants or their beneficiaries and shall hold the assets of the Trust
     for the benefit of the Company's general creditors. Nothing in this Trust
     Agreement shall in any way diminish any rights of Plan participants or
     their beneficiaries to pursue their rights as general creditors of the
     Company with respect to Benefits due under the Plan or otherwise.

         (d) Trustee shall resume the payment of Benefits to Plan participants
     or their beneficiaries in accordance with Article III of this Trust
     Agreement only after the Trustee has determined that the Company is not
     Insolvent (or is no longer Insolvent), or if a regulatory agency or court
     of competent jurisdiction otherwise so orders.

     4.3 Provided that there are sufficient assets, if Trustee discontinues the
payment of Benefits from the Trust pursuant to Section 4.2 hereof and
subsequently resumes such payments, the first payment following such
discontinuance shall include the aggregate amount of all payments due to Plan
participants or their beneficiaries under the terms of the Plan for the period
of such discontinuance, less the aggregate amount of any payments made to Plan
participants or their beneficiaries by the Company in lieu of the payments
provided for hereunder during any such period of discontinuance.

     4.4 In the case of the Trustee's actual knowledge of or determination that
the Company is Insolvent, Trustee shall deliver the assets of the Trust to
satisfy claims of the Company's general creditors as directed by a regulatory
agency or a court of competent jurisdiction.

     4.5 The establishment and funding of this Trust by the Company is solely
for the purpose of facilitating payment of Supplemental Benefits to participants
and their beneficiaries under the Plan, but in no way shall the establishment or
existence of this Trust relieve the Company of its obligations under the Plan,
impose any additional



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obligation on the Company separate and apart from those assumed by the Company
under the Plan, or increase the rights and benefits of the Plan participants and
their beneficiaries.

                                    ARTICLE V

                               PAYMENTS TO COMPANY

     5.1 Except as provided in Article IV hereof and this Section 5.1, after the
Trust has become irrevocable, the Company shall have no right or power to direct
Trustee to return to the Company or to divert to others any of the Trust assets
before all payment of Benefits have been made to Plan participants and their
beneficiaries pursuant to the terms of the Plan. Notwithstanding any provision
of this Trust Agreement to the contrary and prior to a Change in Control, if it
is determined by the Plan's actuary and so certified, that certain Trust assets
will never be required to pay Supplemental Benefits to Plan participants or
beneficiaries (because, for example, of any difference between actual
requirements and expected actuarial requirements), such excess assets shall be
returned to Company, but only to the extent that such return does not cause the
value of the total Trust assets to be less than one hundred thirty percent
(130%) of the present value of projected Supplemental Benefits, with such
present value to be determined on the basis of actuarial assumptions applied by
mutual agreement of the Company and the actuary. Upon and after a Change in
Control, such assets may be returned to Company only after all Supplemental
Benefits have been fully distributed to or on behalf of all Plan participants
and beneficiaries.


                                   ARTICLE VI

                  THE RIGHTS OF THE PARTICIPANTS AND CREDITORS
                               TO THE TRUST ESTATE

     6.1 As provided in Section 2.4 hereof, neither the Plan participants nor
anyone claiming under such participants shall have any present ownership or
present beneficial interest (including a security interest) or preferred claim
of any kind in the assets of the Trust prior to the time provided in the Plan
for the payment of Supplemental Benefits. Prior to that time, the rights of the
participants under the Plan and the rights of anyone claiming under the
participants shall be limited to general unsecured, contractual rights against
the Company. As a precondition to the execution of this Trust Agreement by the
Company, each person meeting the qualification requirements of Section 2.1 of
the Plan shall have waived in writing any priority such person may have under
any state or federal law with respect to any claims such person may have against
the Company under the Plan or the Trust Fund beyond the rights such person would
have as a general creditor of the Company. After the execution of this Trust
Agreement by the Company, any person who thereafter qualifies for coverage under
the Plan shall, as provided for in Section 2.1 of the Plan, execute the written
waiver described herein prior to becoming a participant in the Plan. The Trustee
shall not be responsible for determining whether any waiver referred to in this
Section 6.1 has been obtained.

     6.2 As provided in Section 14.2 hereof, the assets of the Trust shall not
be subject to legal process or the claims of any creditor of the participants or
of anyone claiming under the participants, whether such claim arises out of any
debts, contracts,




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liabilities (including claim for child support or alimony), torts or any other
source whatsoever.

                                   ARTICLE VII

                              INVESTMENT AUTHORITY

     7.1 Discretionary authority for the management and control of the assets of
the Trust may be retained, allocated or delegated, as the case may be, for one
or more purposes, to and among the Asset Managers by the Company in its absolute
discretion; provided, however, that for a period of three (3) years following a
Change in Control the Company may not remove or appoint an Asset Manager without
the written consent of a majority of the Plan participants. Any investment
policy, and any related guidelines, established by the Company from time to
time, shall be communicated to the affected Asset Manager and monitored by the
Company. The assets of the Trust shall be invested and reinvested, without
distinction between principal and income, at such time or times in such
investments pursuant to such investment strategies or courses of action and in
such shares and proportions, as each Asset Manager, in its sole discretion,
shall deem advisable, subject to such policies and guidelines, if any.

     7.2 The Company shall promptly notify the Trustee in writing of the
appointment or removal of an Asset Manager and shall specify the portion of the
Trust to be managed by such Asset Manager. Each Asset Manager shall have sole
and complete investment responsibility for the assets of the Trust that are
subject to its discretionary authority or control and the Trustee shall receive,
hold and transfer assets purchased or sold by the Asset Manager in accordance
with the directions of such Asset Manager. The Trustee shall be under no duty or
obligation to review or to question any direction of any Asset Manager, or to
review the securities or any other property held in any Directed Fund with
respect to prudence, proper diversification or compliance with any limitation on
an Asset Manager's authority under this Trust Agreement or the terms of the
Plan, any investment policies and guidelines, or any agreement entered into
between the Company and the Asset Manager or imposed by applicable law, or to
make any suggestions or recommendations to any Asset Manager or the Company with
respect to the retention or investment of any asset in a Directed Fund. The
Trustee shall have no authority to take any action or to refrain from taking any
action with respect to any asset of a Directed Fund unless and until it is
directed to do so by the Asset Manager of such Directed Fund or the Company.

     7.3 The Trustee will have no responsibility for any asset allocated to a
Directed Fund upon the resignation or removal of an Asset Manager unless and
until the Trustee has been notified in writing by the Company that the Asset
Manager's authority will be terminated or relinquished, and the Trustee has
agreed in writing to become an Asset Manager or that such assets are to be
integrated with a Discretionary Fund, as the case may be. In no event shall the
Trustee be liable for any losses to the Trust resulting from the disposition of
any investment made for a Directed Fund or for the retention of any illiquid or
unmarketable investment or for the holding of any other asset acquired therefor
if the Trustee is unable to dispose of such investment because of any securities
laws restrictions or if an orderly liquidation of such investment is difficult
under prevailing conditions, or for failure to comply with any investment or
diversification limitations imposed by the Company, or for any other violation
of the terms of this Trust Agreement, any Plan or applicable law or laws, as a
result of the addition of such assets to the Discretionary Fund.



                                      -9-
<PAGE>   12

                                  ARTICLE VIII

                 DUTIES, POWERS AND RESPONSIBILITIES OF TRUSTEE
                               AND ASSET MANAGERS

     8.1 Trustee shall perform all of its fiduciary duties 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; provided,
however, that nothing herein shall be construed to impose any responsibility on
the Trustee with respect to transactions effected or assets managed within a
Directed Fund or any other duty with respect to which the Trustee has no
responsibility under this Agreement.

     8.2 Without in any way limiting the powers and discretions conferred upon
the Asset Managers by the other provisions of this Trust Agreement or by law,
each Asset Manager shall have the power to invest and reinvest the assets of the
Trust, in its sole discretion, in Securities or Other Property. "Securities or
Other Property" means investments in any properties, real or personal or mixed,
wherever situated, including, but not limited to, preferred and common stocks or
any other interest in any corporation; securities; life insurance contracts;
governmental or corporate notes, bonds, or obligations; trust and participation
certificates; leaseholds, beneficial interests, fee titles, mortgages, deeds of
trust, leases on real property, contracts to sell real property, and other
interests in realty, shares or interests in real estate investment trusts,
common trust funds and mutual funds; insurance and annuity policies; and any
other evidence of indebtedness or ownership, and any other property of any kind
or nature whatsoever (unless prohibited by law under a provision which may not
be waived); provided, however, that securities issued by the Company or any
affiliate of the Company are not "Securities or Other Property." In no event may
an Asset Manager invest in securities (including stock or rights to acquire
stock) or obligations issued by the Company, other than a de minimis amount held
in common investment vehicles in which such Asset Manager invests. All rights
associated with assets of the Trust shall be exercised by the Asset Manager or
the person designated by the Asset Manager, and shall in no event be exercisable
by or rest with Plan participants.

     When acting hereunder, except as provided otherwise by this Section 8.2
hereof, Asset Manager shall have the following powers with respect to any and
all monies and Securities or Other Property at any time held by Trustee and
constituting part of the assets of the Trust hereunder:

         (a) To purchase or subscribe for Securities or Other Property and to
     retain them in trust; to sell any Securities or Other Property at any time
     held in the Trust at either public or private sale for cash or other
     consideration or on credit at such time or times and on such terms and
     conditions as may be deemed appropriate; to exchange such Securities or
     Other Property and to grant options for the purchase or exchange thereof,
     and to convey, partition, or otherwise dispose of, with or without
     covenants, including covenants of warranty of title, any Securities or
     Other Property free of all trusts.

         (b) To oppose, or consent to and participate in, any plan of
     reorganization, consolidation, merger, combination, or other similar plan;
     to



                                      -10-
<PAGE>   13
     oppose or to consent to any contract, lease, mortgage, purchase, sale, or
     other action by any corporation pursuant to such plan, and to accept and
     retain any Securities or Other Property issued under any such plan; to
     deposit any Securities or Other Property with any protective,
     reorganization or other similar committee; to delegate discretionary power
     thereto and to pay and agree to pay any part of Trustee's expenses and
     compensation and any assessments levied with respect to any such Securities
     or Other Property so deposited.

         (c) To exercise all conversion and subscription rights pertaining to
     any Securities or Other Property.

         (d) To collect and receive any and all monies and Securities or Other
     Property of whatsoever kind or nature due or owing or belonging to the
     Trust, and to give full discharge and acquittance therefor.

         (e) To exercise all voting rights with respect to any investment held
     in the Trust, and, in addition thereto, to grant proxies, discretionary or
     otherwise, to appoint one or more individuals or corporations or voting
     trustees under voting trust agreements and to delegate to such voting
     trustees discretion to vote.

         (f) To acquire any real estate by purchase or lease, or as the result
     of any foreclosure, liquidation, or other salvage or any investment
     previously made, or otherwise; and to manage, operate, sell, improve, or
     demolish any buildings in whole or in part, and to erect buildings,
     partition, mortgage, or lease for any term or terms of years, even though
     such period extends beyond the term of the Trust, grant options to renew or
     purchase, any such real estate, upon such terms and conditions as may be
     deemed proper.

         (g) To borrow money from others for such purposes, including payment of
     Benefits hereunder, as may be deemed proper, and for the sum or sums so
     borrowed or advanced, Asset Manager may issue the Trust's promissory note
     as investment manager and secure the repayment thereof by creating a lien
     upon any assets of the Trust.

         (h) To acquire property returning no income or slight income for such
     period as an Asset Manager shall deem advisable; to retain any assets which
     shall be delivered from the trustee of a prior trust; to retain in cash or
     other property unproductive of income any amount of the Trust as deemed
     advisable.

         (i) To invest in interest-bearing deposits in Asset Manager's or an
     affiliate of Asset Manager's, commercial banking department, including, but
     not limited to, investments in time deposits, savings deposits,
     certificates of deposit, or time accounts which bear a reasonable rate of
     interest.

         (j) To surrender any life insurance contract held in Trust and, except
     as provided in Section 8.10, to exercise any incident of ownership with
     respect to any such life insurance contract.



                                      -11-
<PAGE>   14

     8.3 In addition, the Trustee is hereby authorized

         (a) To cause any Securities or Other Property to be registered in, or
     transferred into, Trustee's name as Trustee or held in the name of one or
     more of Trustee's nominees or to retain them unregistered or in form
     permitting transferability by delivery, but the books and records of
     Trustee shall at all times show such Securities or Other Property are part
     of the Trust; to deposit or arrange for the deposit of securities in a
     qualified central depository even though, when so deposited, such
     securities may be held in the name of the nominee of such depository with
     other securities deposited therein by other persons, or to deposit or to
     arrange for the deposit of any securities issued by the United States
     Government, or any agency or instrumentality thereof, with a federal
     reserve bank (provided that the books and records of Trustee shall at all
     times show that all such securities are part of the Trust).

         (b) To employ on behalf of the Trust suitable agents, accountants, and
     counsel, who may be counsel to the Company or the Trustee, to assist it in
     determining or performing its duties or obligations hereunder, and to pay
     their reasonable expenses and compensation from the Trust to the extent not
     paid by the Company.

         (c) 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 whenever, in Trustee's judgment, any interest of the
     Trust so requires, and to represent the Trust in all suits or legal
     proceedings in any court of law or equity or before any other body or
     tribunal.

         (d) Pending investment of cash, to hold such cash in Trustee's, or an
     affiliate of Trustee's, non-interest bearing accounts; and to hold such
     non-interest bearing cash balances as Trustee shall deem reasonable or
     necessary to meet anticipated distributions from or administrative costs of
     the Trust.

         (e) Generally to do all such acts, to make, execute, acknowledge, and
     deliver any and all deeds, leases, assignments, documents of transfer, and
     conveyances, receipts, releases, agreements, and without limitation by the
     foregoing, to execute any and all other instruments, take all such
     proceedings and exercise all such rights and powers with relation to any
     Securities or Other Property constituting a part of the Trust to the same
     extent as an individual might do with respect to his own property.

     8.4 When the Trustee delivers property against payment, delivery of the
property and receipt of payment may not be simultaneous. In such case, the risk
of non-receipt of payment shall be the Trust's, and the Trustee shall have no
liability therefor. All credits to the Trust of the anticipated proceeds of
sales and redemption of property and of anticipated income from property shall
be conditional upon receipt by the Trustee of final payment and may be reversed
to the extent final payment is not received. At the discretion of the Trustee,
the Trust may make use of such conditional credits. To the extent such credits
do not become unconditional by receipt of final payment, the Trust shall
reimburse the Trustee upon demand for the amount of such conditional credits.


                                      -12-
<PAGE>   15
When the Trustee is to receive property, it is authorized to accept documents in
lieu of such property as long as such documents contain the agreement of the
issuer thereof to deliver such property to the Trustee. The Trustee may, in its
discretion, advance funds to the Trust to facilitate the settlement of any
trade. In the event of such an advance, the Trustee shall immediately reimburse
the Trust for the amount thereof.

     8.5 During the term of this Trust, all income received by the Trust, net of
expenses and taxes, shall be accumulated and reinvested.

     8.6 Trustee shall keep accurate and detailed records of all investments,
receipts, disbursements, and all other transactions hereunder. All records
relating thereto shall be open to inspection and audit at all reasonable times
by the Company or by any person designated by the Company. At such intervals as
the Company and the Trustee mutually agree, and as of the date of the removal or
resignation of Trustee, Trustee shall deliver to the Company a written account
of its administration of the Trust, setting forth all investments, receipts,
disbursements and other transactions effected by Trustee during the period from
the date of Trustee's last such account, including a description of all
securities and investments purchased and sold with the cost or net proceeds of
such purchases or sales (accrued interest paid or receivable being shown
separately), and showing all cash, securities and other property held in the
trust at the close of such period. Any such account shall be deemed an account
stated and accepted and approved by the Company, and the Trustee shall be
relieved and discharged to all persons with respect to all matters and things
contained in such statement as though such account had been settled and allowed
by a judgment or decree of a court of competent jurisdiction in an action or
proceeding to which the Company and all persons having any beneficial interest
in the Trust were parties, unless the Company shall have filed with the Trustee
specific written exceptions or objections to any such statement within ninety
(90) days of receipt thereof by the Company.

     8.7 The Trustee will determine the value of the Trust as of each reporting
date under Section 8.6. Except in the case of an investment in which amortized
cost is the valuation method designated, assets will be valued at their market
values at the close of business on such date, or, in the absence of readily
ascertainable market values, at such values as the Trustee determines in
accordance with methods consistently followed and uniformly applied or obtained
as provided below. The Company acknowledges and agrees that in the normal course
of valuing assets, the Trustee may rely on pricing information provided by
recognized pricing services which the Trustee deems to be reliable or provided
by the Asset Manager or dealers or sponsors of pooled investment vehicles
("dealers"), and that the Trustee does not verify, warrant or represent the
accuracy or completeness of such information, and shall not be liable for any
diminution or inflation in the value of any assets as a result of any inaccurate
or incomplete information furnished or transmitted by such pricing services or
the Asset Managers or dealers. The Trustee may rely for all purposes of this
Trust Agreement on the latest valuation information submitted to it even if such
information predates the purported valuation date. The Company will provide or
cause the Asset Managers to provide the Trustee with all information needed by
the Trustee to value such assets and to report and account under this Trust
Agreement.

     8.8 The Trustee shall have the right, at the expense of the Trust, to apply
at any time to a court of competent jurisdiction for judicial settlement of any
account of the Trustee not previously settled as herein provided or for the
determination of any question of construction or for instructions. In any such
action or proceeding it shall be necessary to join as parties only the Trustee
and the Company (although the Trustee may also join



                                      -13-
<PAGE>   16

such other persons as it may deem appropriate), and any judgment or decree
entered therein shall be conclusive.

     8.9 A third party dealing with Trustee shall not make, or be required by
any person to make, any inquiry concerning the authority of Trustee to take or
omit any action or whether Trustee has been authorized or directed by the
Company, but each such person shall be fully protected in relying upon the
certificates of Trustee that Trustee has authority to take such proposed action.
No third party shall be required to follow the application by Trustee of any
monies or Securities or Other Property paid or delivered to Trustee.

     8.10 To the extent not inconsistent with the express provisions hereof,
enumeration of any power herein shall not be by way of limitation but shall be
cumulative and construed as full and complete power in favor of Trustee. In
addition to the authority specifically herein granted, except as provided in
Article VII, Trustee shall have such power to do all acts as may be deemed
necessary for full and complete management of the Trust and appropriate to carry
out the purposes of this Trust. Trustee shall have, without exclusion, all
powers conferred on trustees by applicable law, unless expressly provided
otherwise herein, provided, however, that if an insurance policy is held as an
asset of the Trust, Trustee shall have no power to name a beneficiary of the
policy other than the Trust, to assign the policy (as distinct from conversion
of the policy to a different form) other than to a successor Trustee, or to loan
to any person the proceeds of any borrowing against such policy. None of the
powers granted to an Asset Manager under this Article, however, shall be
construed to allow an Asset Manager to purchase, exchange, or otherwise deal
with or dispose of the corpus or the income from the corpus for less than
adequate consideration.

     8.11 The Trustee shall be fully protected in relying upon a certification
by the Board of Directors of the Company signed by a majority of all the members
thereof, or by any member, or the secretary thereof, if designated by all such
members to act for the Board of Directors of the Company with respect to any
written instruction, written direction or written approval by said Board, except
that such secretary or individual member shall not be authorized to direct any
distribution to himself. The Trustee shall be protected in relying upon a
specimen signature of each member and the secretary, and in continuing to rely
upon such certification until a subsequent certification is filed with the
Trustee, or in relying upon the certification by the Company or the Company's
designee in lieu of said Board of Directors, in all respects for the
administration of the Plan of which this Trust is a part. The Company shall
cause each Investment Manager to file with the Trustee a certified list of the
names and specimen signatures of those individuals authorized to direct the
Trustee on its behalf.

     8.12 Any action by the Company shall be evidenced by a written instrument
executed in accordance with Section 8.11 hereof. The Trustee shall be fully
protected in acting upon any certifications, instructions, notices, directions,
requests or approvals and other communications ("Instructions"), howsoever
transmitted, received by the Trustee and purporting to be from the Company or an
Investment Manager which the Trustee reasonably believed to be from such person,
each such Instruction constituting a certification by the person so giving that
such Instruction is in conformity with the terms of the Plan, the Trust and/or
other related documents, and the Trustee shall be fully protected in omitting to
act in the absence of Instructions. The Trustee shall have the right to assume,
in the absence of notice in writing to the contrary, that no event



                                      -14-
<PAGE>   17

constituting a change in, or terminating, the authority of any person, including
any Investment Manager, has occurred.

     8.13 Notwithstanding any powers granted to Trustee pursuant to this Trust
Agreement or to applicable law, Trustee shall not have any power that could give
this Trust the objective of carrying on a business and dividing the gains
therefrom, within the meaning of Section 301.7701-2 of the Procedure and
Administrative Regulations promulgated pursuant to the Internal Revenue Code.

                                   ARTICLE IX

                   INDEMNIFICATION; LIABILITIES OF THE TRUSTEE

     9.1 The Trustee shall be held harmless by the Company from and against any
claim, liability, loss, damage or expenses (including, but not limited to,
reasonable attorneys' fees and expenses incurred in preparing, investigating or
defending any claim) that may be asserted against the Trustee arising out of any
action taken or omitted by the Trustee pursuant to this Trust Agreement, except
due to the Trustee's own negligence or willful misconduct. If the Company does
not pay any claim, liability, loss, damage or expense under this Section or
Article X, the Trustee may obtain payment from the Atmos Energy Corporation
Legal Defense Fund Trust of which Trustee is the trustee for all amounts other
than the payment of any Supplemental Benefits due under the Plan, but until so
paid such amounts shall constitute a charge against, and may be paid from this
Trust. Notwithstanding the foregoing provisions of this Section 9.1, the Company
shall be and remain liable for any Benefits due and owing under the Plan.

     9.2 If the Trustee undertakes or defends any claim, litigation, action,
proceeding or appeal arising in connection with this Trust unless any such
defense shall be due to the Trustee's own neglect or willful misconduct, the
Company agrees to indemnify the Trustee against the Trustee's costs, expenses,
losses, damages, and liabilities (including, without limitation, reasonable
attorneys' fees and expenses incurred in preparing, investigating or defending
any claim) relating thereto and to be primarily liable for such payments, and to
make periodic payments in respect of such fees and expenses during the course of
any such proceedings. In any action taken by the Trustee pursuant to this
Section 9.2, Section 8.3(c) or otherwise, the Trustee shall be indemnified by
the Company or, if not, the Trustee may obtain payment from the Atmos Energy
Corporation Legal Defense Fund Trust, but until so paid shall constitute a
charge against, and may be paid from this Trust.

                                    ARTICLE X

                       TRUSTEE'S COMPENSATION AND EXPENSES

     10.1 The Trustee shall be paid such reasonable compensation as shall from
time to time be agreed upon in writing by the Company and the Trustee. In
addition, the Trustee shall be reimbursed for any reasonable expenses, including
reasonable accounting and legal fees incurred by it as Trustee. Company shall
pay all such administrative and Trustee's fees and expenses. If not so paid,
such fees and expenses shall be paid from the Atmos Energy Corporation Legal
Defense Fund Trust, but until so paid shall constitute a charge against, and may
be paid from this Trust.



                                      -15-
<PAGE>   18

                                   ARTICLE XI

                                      TAXES

     11.1 All income, deductions and credits attributable to the Trust belong to
the Company and will be included on the Company's income tax returns. The
Company shall pay any Federal, state, local or other taxes imposed or levied
with respect to the assets and/or income of the Trust or any part thereof under
existing or future laws. Upon furnishing the Trustee with evidence reasonably
required by the Trustee of any such tax payments made directly by the Company,
the Company shall be entitled to receive reimbursement from the assets of the
Trust for the full amount of such taxes paid by it. The Trustee shall promptly
notify the Company of any notice it receives relating to any taxes imposed or
levied with respect to the assets and/or income of the Trust. If the Trustee
receives notice that any such taxes are not timely paid by the Company, the
Trustee shall pay such taxes from the assets of the Trust to the extent
sufficient therefor, prior to any payments to Participants, after notifying the
Company as herein provided. As provided in Article III, the Trustee shall deduct
any taxes required to be withheld with respect to any payments made to
Participants pursuant to the Trust, with any such taxes being paid out of the
Trust.

                                   ARTICLE XII

                       RESIGNATION AND REMOVAL OF TRUSTEE;
                            APPOINTMENT OF SUCCESSOR

     12.1 Trustee shall serve until a successor shall be appointed. Trustee may
resign at any time by written notice to the Company, which shall be effective
thirty (30) days after receipt of such notice unless the Company and Trustee
agree otherwise. The Company may remove Trustee at any time upon giving thirty
(30) days' written notice to Trustee; however, for a period of three years
following a Change in Control any such removal shall require the written consent
of a majority of the Plan participants at the time of such removal. In either
case, such notice may be wholly or partially waived by the party to whom it is
due.

     12.2 Upon resignation or removal of Trustee and appointment of a successor
Trustee, all assets shall subsequently be transferred to the successor Trustee.
The Trustee shall use its best efforts to complete the transfer within thirty
(30) days after receipt of notice of resignation, removal or transfer, unless
the Company extends the time limit.

     12.3 If Trustee resigns or is removed, a successor shall be appointed, in
accordance with Section 12.4 hereof, by the effective date of resignation or
removal under Section 12.1 hereof. If no such appointment has been made, Trustee
may apply to a court of competent jurisdiction for appointment of a successor or
for instructions. All expenses of Trustee in connection with the proceeding
shall be allowed as administrative expenses of the Trust.

     12.4 If Trustee resigns or is removed in accordance with Section 12.1
hereof, the Company may appoint any third party, such as a bank trust department
or other party that may be granted corporate trustee powers under state law, as
a successor Trustee; however, for a period of three years following a Change in
Control any such appointment



                                      -16-
<PAGE>   19

shall require the written consent of a majority of the Plan participants at the
time of such appointment. The appointment shall be effective when accepted in
writing by the new Trustee. The appointment of a new Trustee shall be by a
written instrument, duly acknowledged, delivered to the Trustee so removed, to
the successor Trustee, and to the Company. Upon resignation or removal of
Trustee, Trustee shall refund any unearned portion of any fee or compensation
previously collected by Trustee hereunder. The resigning or removed Trustee,
upon receipt of acceptance in writing of the Trust by the successor Trustee,
must execute all documents and do all acts reasonably necessary to vest the
title of record in any successor Trustee. The successor Trustee shall have the
same powers and duties as those conferred upon Trustee hereunder.

                                  ARTICLE XIII

                            AMENDMENT OR TERMINATION

     13.1 This Trust Agreement may be amended by a written instrument executed
by Trustee and the Company; however, for a period of three years following a
Change in Control any such amendment shall require the written consent of a
majority of the Plan participants at the time of such amendment. If any such
amendment is made at the request or direction of a person who has entered into
an agreement with the Company, the consummation of which would constitute a
Change in Control, or was otherwise in connection with or in anticipation of a
Change in Control (whether or not the Change in Control ever occurs), then for
all purposes hereof, such amendment shall be deemed to have been made following
a Change in Control. Notwithstanding the foregoing, the Company shall ensure
that no such amendment shall conflict with the terms of the Plan or shall make
the Trust revocable after it has become irrevocable in accordance with Section
2.2 hereof.

     13.2 The Trust shall not terminate until the date on which all Plan
participants and their beneficiaries are no longer entitled to Supplemental
Benefits pursuant to the terms of the Plan, unless sooner revoked in accordance
with Section 2.2 hereof; provided, however, the Trust shall terminate prior to
such date if and when all of the assets of the Trust are consumed in
satisfaction of the claims of the general creditors of the Company pursuant to
Article IV. Upon satisfaction of all liabilities under the Plan with respect to
all participants and beneficiaries, the Company, pursuant to a resolution of its
Board of Directors, may terminate the Trust by delivery to the Trustee of (i) a
certified copy of such resolution, (ii) a certification of the Plan's enrolled
actuary confirming that all liabilities under the Plan have been satisfied, and
(iii) a written instrument of termination duly executed and acknowledged in the
same form as this Trust Agreement. Upon termination of the Trust in accordance
with this Section 13.2, any assets remaining in the Trust shall be returned to
the Company.



                                      -17-
<PAGE>   20

                                   ARTICLE XIV

                                  MISCELLANEOUS

     14.1 Each provision of this Trust is intended to be independent of each
other provision. Any provision of this Trust Agreement prohibited by law shall
be ineffective to the extent of any such prohibition, without invalidating the
remaining provisions hereof. If any provision of this Trust is determined in
writing by the Company to be, or is held by any court, tribunal, board or other
authority of competent jurisdiction to be, void or invalid as to any participant
or group of participants, such provision shall be disregarded as to such
participant or group of participants and shall be deemed null and void and no
part of this Trust.

     14.2 Except as otherwise required by law, Benefits payable to Plan
participants and their beneficiaries under this Trust Agreement may not be
anticipated, assigned (either at law or in equity), alienated, pledged,
encumbered or subjected to attachment, garnishment, levy, execution or other
legal or equitable process.

     14.3 This Trust Agreement shall be governed by and construed in accordance
with the laws of the State of New York. Nothing in this Trust Agreement shall be
construed to subject the Trustee created hereunder to ERISA or to cause it to be
treated as other than a grantor trust.

     14.4 All reasonable expenses incurred in maintaining and administering the
Trust pursuant to the provisions of this Trust Agreement shall be paid from the
assets of the Trust unless paid by the Company.

     14.5 The headings and subheadings of this Trust have been inserted for
convenience of reference and are to be ignored in any construction of the
provisions hereof.

     14.6 Wherever any words are used herein in the masculine, feminine or
neuter gender, they shall be construed as though they were also used in another
gender in all cases where they would so apply, and whenever any words are used
herein in the singular or plural form, they shall be construed as though they
were also used in the other form in all cases where they would so apply.

     14.7 All provisions of this Trust Agreement shall be interpreted and
applied in a uniform, nondiscriminatory manner.

     14.8 The Trustee's obligations are limited to those set out in this Trust
Agreement. No additional duties or obligations shall be imposed on the Trustee
or implied from the terms of this Trust Agreement. In case of any conflict or
inconsistency between the terms of this Trust Agreement and the Plan, in
determining the obligations and responsibilities of the Trustee, the terms of
this Trust Agreement shall control.

     14.9 This Trust Agreement shall be binding upon and inure to the benefit of
any successor(s) or assign(s) of the Company or the Trustee, or any of its
businesses, in whole or in part, as the result of merger, consolidation,
reorganization, transfer of assets or otherwise, and any subsequent successor
thereto. In the event of any such merger, consolidation, reorganization,
transfer of assets or other similar transaction, the successor to the Company or
the Trustee or its business or relevant part thereof or any subsequent



                                      -18-
<PAGE>   21

successor thereto shall promptly notify the other party hereto in writing of its
successorship.

     14.10 The undertakings and obligations of the Company, and the entitlements
of the Trustee, under Articles IX and X of this Trust Agreement shall survive
the termination, amendment or restatement of this Trust Agreement, or the
resignation or removal of the Trustee.

     14.11 Until notice be given in writing to the contrary, all instructions,
notices and other communications shall be delivered or sent:



         If to the Trustee to:          Bankers Trust Company of the Southwest
                                        500 North Akard, Suite 3900
                                        Dallas, TX  75201
                                        Attn:  Elizabeth B. Smith


         If to the Company to:          Atmos Energy Corporation
                                        5430 LBJ Freeway, Suite 1800
                                        Dallas, TX  75240
                                        Attn:  Vice President - Human Resources


                                   ARTICLE XV

                                 EFFECTIVE DATE

     15.1 The effective date of this Trust Agreement shall be the day and year
first written above.




                                      -19-
<PAGE>   22





         IN WITNESS WHEREOF, the Company and Trustee by their duly authorized
officers have signed this Trust Agreement on the day and year first written
above.

                                                   ATMOS ENERGY CORPORATION

Attest:


By:   /s/ Shirley A. Hines               By:    /s/ Wynn McGregor
   -------------------------------          ------------------------------------
Name: Shirley A. Hines                   Name:  Wynn McGregor
     -----------------------------            ----------------------------------
Title: Corporate Secretary               Title: Vice President, Human Resources
      ----------------------------             ---------------------------------


                                                     BANKERS TRUST COMPANY

Attest:

By:  /s/ James F. Shanley                By:    /s/ Frank Eipper
   -------------------------------          ------------------------------------
Name: James F. Shanley                   Name:  Frank Eipper
     -----------------------------            ----------------------------------
Title: Vice President                    Title: Vice President
      ----------------------------             ---------------------------------



                                      -20-
<PAGE>   23



STATE OF TEXAS               )
                             )ss
COUNTY OF _______________    )


     BEFORE ME, the undersigned, a Notary Public in and for the said County and
State, on this day personally appeared, of ATMOS ENERGY CORPORATION, known to
me to be the person and officer whose name is subscribed to the foregoing
instrument, and acknowledged to me that he executed the same for the purposes
and consideration therein expressed, in the capacity therein stated, and as the
act and deed of said corporation.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE this _______ day of ____________
___________________________, 2000.


                                     -------------------------------------------
                                     Notary Public in and for the State of Texas



My Commission Expires:

--------------------------



STATE OF __________________  )
                             )ss
COUNTY OF _________________  )


         On the ______ day of __________________, 2000, before me personally
came ____________________________ to me known, who being by me duly sworn, did
depose and say: that he/she resides in _____________________________; that
he/she is the __________________ of BANKERS TRUST COMPANY, the corporation
described in and which executed the above instrument; that he/she knows the seal
of said corporation; that the seal affixed to said instrument is such corporate
seal; that it was so affixed by order of the Board of Directors of said
corporation, and that he/she signed his/her name thereto by like order.


                                     -------------------------------------------
                                     Notary Public




                                      -21-