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                                                                   EXHIBIT 10.76







                    TIPPERARY OIL & GAS (AUSTRALIA) PTY. LTD.
                                (ACN 077 536 871)



                                       And



                             ENERGEX RETAIL PTY LTD
                                (ACN 078 849 055)








                              GAS SUPPLY AGREEMENT












                                                                        MAY 2000


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<TABLE>
<CAPTION>




   TABLE OF CONTENTS
   <S>   <C>                                                                                                    <C>
   1.    INTERPRETATION........................................................................................5
      1.1   Definitions........................................................................................5
      1.2   General............................................................................................7
      1.3   Headings...........................................................................................9
      1.4   Business Day.......................................................................................9
   2     RELATIONSHIP OF THE PARTIES...........................................................................9
      2.1   Separate Agreement with the Sellers................................................................9
      2.2   Several Liability..................................................................................9
      2.3   Parties Not Released...............................................................................9
      2.4   Common Stream......................................................................................9
   3.    TITLE TO CONTRACT GAS.................................................................................9
   4.    DELIVERY.............................................................................................10
   5.    SPECIFICATIONS.......................................................................................10
   6.    QUANTITY AND PROCEDURES FOR THE SUPPLY OF CONTRACT GAS...............................................10
      6.1   Contract Quantities...............................................................................10
      6.2   Reduction of MDQ by Buyer.........................................................................11
      6.3   Reduction of MDQ by Sellers.......................................................................12
      6.4   Nominations.......................................................................................13
      6.5   Make up Gas.......................................................................................14
      6.6   Field Failure Event...............................................................................14
   7.    DEDICATION OF RESERVES AND COMMITMENT TO DRILL.......................................................15
   8.    MEASUREMENT OF VOLUMES AND REGULATION OF PRESSURES...................................................15
   9.    CONTRACT PRICE.......................................................................................16
   10.   BILLING AND METHOD OF PAYMENT........................................................................17
      10.1  Monthly Statement.................................................................................17
      10.2  Reconciliation Period Statement...................................................................17
      10.3  Payment...........................................................................................17
      10.4  Rebate by Sellers to Buyer........................................................................18
      10.5  Interest..........................................................................................18
      10.6  Disputed Statement................................................................................18
   11.   FORCE MAJEURE........................................................................................18
      11.1  Definition........................................................................................18
      11.2  Consequences of Force Majeure.....................................................................19
      11.3  Notification and Diligence........................................................................20
      11.4  Liability Not Relieved............................................................................20
      11.5  Prolonged Force Majeure...........................................................................21
   12.   TERM OF AGREEMENT....................................................................................21
   13.   DEFAULT..............................................................................................21
   14.   ASSIGNMENT...........................................................................................21
      14.1  Assignment by Buyer...............................................................................21
      14.2  Assignment by the Sellers.........................................................................22
   15.   WARRANTIES...........................................................................................22
   16.   CONDITIONS PRECEDENT.................................................................................22
   17.   DAMAGES..............................................................................................23
   18.   AUDITING.............................................................................................23
   19.   CONFIDENTIALITY......................................................................................23
   20.   ENTIRE AGREEMENT.....................................................................................24
   21.   CESSATION OF INDIVIDUAL CLAUSES......................................................................24
   22.   LAW AND DISPUTE RESOLUTION...........................................................................24
      22.1  Jurisdiction......................................................................................24
   23.   AMENDMENTS...........................................................................................25
   24.   NOTIFICATION.........................................................................................25
      24.1  Giving of Notices.................................................................................25
      24.2  Timing of Receipt.................................................................................25
      24.3  Addresses.........................................................................................26
   25    TERMINATION..........................................................................................27
   26.   COUNTERPARTS.........................................................................................28

SCHEDULE  1...................................................................................................29
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<TABLE>

<S>                                                                                                            <C>
   CONTRACT PRICE.............................................................................................29


SCHEDULE  2...................................................................................................30


   SPECIFICATIONS.............................................................................................30


SCHEDULE  3...................................................................................................32


   METERING METHOD SCHEDULE...................................................................................32


SCHEDULE  4...................................................................................................33


   CONTRACT AREAS.............................................................................................33


SCHEDULE 5....................................................................................................34


   OWNERSHIP PERCENTAGE.......................................................................................34


SCHEDULE 6....................................................................................................35


   MAXIMUM DAILY QUANTITY.....................................................................................35
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                               GAS SALES AGREEMENT


THIS AGREEMENT is made the                   day of                        2000

BETWEEN:


         Those parties whose names are set out in Schedule 5 (herein called the
         "Sellers")

AND

         ENERGEX Retail Pty Ltd (ACN 078 849 055) having offices at 150
         Charlotte St, Brisbane, Queensland, 4000 ( herein called the "Buyer").



RECITALS


A.       The Sellers have represented to Buyer that, to the knowledge of the
         Sellers, they intend to develop sufficient Contract Gas resources based
         on coal seam methane, possess the necessary expertise and have entered
         into all necessary binding transportation and delivery agreements with
         transporters of Contract Gas to safely supply Buyer's Contract Gas
         requirements to the Delivery Point.

B.       Buyer trades gas in the Queensland gas market.

C.       Buyer wishes to purchase certain quantities of Contract Gas from the
         Sellers, each of whom is willing to sell its Ownership Percentage of
         those quantities of Contract Gas to the Buyer.

D.       In reliance on the representations in Recital A. Buyer is entering into
         this Agreement with the Sellers to set out the terms and conditions
         under which the purchase and sale of Contract Gas may take place.

E.       Buyer acknowledges that, in performing its obligations under this
         Agreement, it is acting as the agent of Allgas Energy Ltd (ACN 009 656
         446).

F.       The Sellers warrant that they have documented approval from the TCW
         Asset Management Company for funding sufficient to implement the
         minimum twenty well field development program on ATP526P.




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THE PARTIES AGREE AND DECLARE AS FOLLOWS:

1.      INTERPRETATION

1.1      DEFINITIONS


         In this agreement, unless the context otherwise requires:

         "AGREEMENT" means this agreement as may be amended from time to time
         together with its schedules, annexures and attachments;

         "BUSINESS DAY" means any day of the week except Saturdays, Sundays and
         days which have been declared as public holidays by the government of
         Queensland;

         "COAL SEAM METHANE" means hydrocarbons in a gaseous state occurring in
         association with coal;

         "COMMENCEMENT DATE" means 1 June 2000;

         "CONTRACT AREA" means the areas described in Schedule 4

         "CONTRACT GAS" means:

         (a)      Coal Seam Methane which meets the Specification; or

         (b)      Off Specification Gas which is delivered and accepted by Buyer
                  in accordance with the provisions of clause 4;

         "CONTRACT PRICE" has the meaning ascribed to it in clause 9;

         "CONTRACT YEAR" means a period commencing at 8.00am on the Commencement
         Date and ending at 8.00am, on the first anniversary of the Commencement
         Date and thereafter each successive period of 12 consecutive months;

         "CUBIC METRE" or "M3" means the amount of Contract Gas which occupies
         one cubic metre when that Contract Gas is at Standard Conditions;

         "DAILY NOMINATION" means, for a particular Day, the quantity of
         Contract Gas, not exceeding MDQ, which Buyer has nominated, pursuant to
         clause 6, for delivery on that Day;

         "DAY" means a period of twenty four (24) consecutive hours, which
         begins and ends at 8.00 am in the morning;

         "DELIVERY POINT" means the inlet flange into the Duke Queensland Gas
         Pipeline or any other point agreed between the Buyer and the Sellers,
         provided that no additional costs shall be incurred by either Party and
         provided that agreement shall not be unreasonably withheld;




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         "DISPOSE" means assign, transfer or otherwise dispose of any legal or
         equitable interest, either in whole or part, whether by sale, lease,
         declaration or creation of a trust or otherwise but does not include
         grant of a security interest;

         "DUKE QUEENSLAND GAS PIPELINE" means the natural gas pipeline referred
         to in Pipeline Licence No 30;

         "FIELD OPERATOR" means the company or organisation who has
         responsibility for the day to day operations of the Contract Area
         defined in Schedule 4.;

         "FIRST AGREEMENT" means the Gas Supply Agreement between Allgas Energy
         Ltd and Tipperary Oil and Gas (Australia) Pty Ltd dated 8 September
         1998;

         "FORCE MAJEURE" has the meaning given in clause 11;

         "GAS ACT" means the Gas Act (Queensland) 1965;

         "GJ" means one gigajoule (1,000,000,000 joules);

         "GROSS HEATING VALUE" and "GHV" mean the energy produced by the
         complete combustion of one Cubic Metre of Contract Gas with air, at an
         absolute pressure of 101.325 kPa and temperature of fifteen (15)
         degrees Celsius, with the Contract Gas and air free of all water
         vapour, the product of combustion cooled to a temperature of fifteen
         (15) degrees Celsius and the water vapour formed by combustion
         condensed to the liquid state, expressed in MJ per Cubic Metre (MJ/m3);

         "INTEREST RATE" refers to a rate of interest that is one percent above
         the ANZ Banking Group Reference Rate;

         "MAKE UP GAS" means that portion of the quantity of Contract Gas which
         Buyer has paid for but not taken in the relevant Month , and where the
         context so requires, means the aggregate of such quantities of Contract
         Gas credited to Buyer in respect of prior Months less any quantities of
         Contract Gas taken by Buyer pursuant to clause 6.5.1;

         "MAXIMUM DAILY QUANTITY" or "MDQ" means the maximum quantity of
         Contract Gas which Buyer can require the Sellers to deliver to the
         Delivery Point on any given Day, subject to clauses 6.2 & 6.3, as set
         out in Schedule 6.

         "MINIMUM MONTHLY QUANTITY" means that quantity of Contract Gas
         calculated by aggregating for each Month, the quantity of Contract Gas
         equivalent to fifty (50) per cent of the MDQ applicable for each Day of
         that Month;

         "MJ" means one megajoule (1,000,000 joules);

         "MONTH" means a period beginning at 8.00 am on the morning of the first
         day of the calendar month and ending at 8.00 am on the morning of the
         first Day of the succeeding calendar Month;

         "OFF-SPECIFICATION GAS" means Coal Seam Methane which does not conform
         to the Specifications;



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         "OWNERSHIP PERCENTAGE" means the Ownership Percentage of the Sellers as
         set out in Schedule 5, as may be varied from time to time in accordance
         with the provisions of this Agreement;

         "PARTY" means either Seller or Buyer as the context may require and
         "PARTIES" shall mean both the Sellers and Buyer;

         "PJ" means one petajoule (1,000,000 GJ);

         "RECONCILIATION PERIOD" means a period commencing at 8.00 am on the
         Commencement Date and ending at 8.00 am on the Day six (6) Months later
         and thereafter each successive period of six (6) consecutive Months;

         "RELATED CORPORATION" A body corporate that is a related body corporate
         of another within the meaning of section 50 of the Corporations Law
         (Queensland).


         "SPECIFICATIONS" means the specifications for Natural Gas prescribed
         from time to time under the Regulations of the Gas Act. The
         specifications applying as at the date of this Agreement are those set
         out in Schedule 2;

         "STANDARD CONDITIONS" means a temperature of fifteen (15) degrees
         Celsius and an absolute pressure of 101.325 kPa;

         "TAKE OR PAY QUANTITY" means the Minimum Monthly Quantity adjusted by
         deducting all amounts of Contract Gas equal to any amount, up to the
         MDQ for each Day, that the Sellers have failed to make available to
         Buyer for nomination (whether due to Force Majeure events or not) or
         has failed to deliver to the Buyer in accordance with the Daily
         Nomination, that the Buyer is obliged to pay for in a Month whether or
         not it has nominated such quantity for delivery;

         "TERM" means the period of time during which this Agreement is in force
         pursuant to clause 12;

         "TJ" means one terajoule (1,000 GJ); and

         "TERMINATION DATE" means either the date five (5) years after the
         Commencement Date, or the date to which the term is extended pursuant
         to clause 12.3 or the date on which this Agreement is terminated
         pursuant to clause 6.2.4, 11, 13, 16.3 or 25, whichever is appropriate.

1.2      GENERAL


         In this Agreement, unless the context otherwise requires:

         1.2.1    a reference to any law, legislation or legislative provision
                  includes any statutory modification or re-enactment of, or
                  legislative provision substituted for, and any statutory
                  instruments issued under that legislation or legislative
                  provision;

         1.2.2    the singular includes the plural and vice versa;



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         1.2.3    a reference to an individual or person includes a corporation,
                  partnership, joint venture, association, authority, trust,
                  state or government and vice versa;

         1.2.4    a reference to any gender includes all genders;

         1.2.5    a reference to a recital, clause, schedule, appendix, annexure
                  or exhibit is to a recital, clause, schedule, appendix,
                  annexure or exhibit of or to this Agreement;

         1.2.6    a recital, schedule, appendix, exhibit, annexure or a
                  description of the parties referred to in this Agreement forms
                  part of this Agreement;

         1.2.7    a reference to any agreement or document is to that agreement
                  or document (and, where applicable, any of its provisions) as
                  amended, novated, supplemented or replaced from time to time;

         1.2.8    a reference to any party to this Agreement or any other
                  document or arrangement includes that party's executors,
                  administrators, substitutes, successors and permitted assigns;

         1.2.9    where an expression is defined, another part of speech or
                  grammatical form of that expression has a corresponding
                  meaning;

         1.2.10   a reference to "DOLLARS" or "$" is to Australian currency;

         1.2.11   a reference to bankruptcy or winding up includes bankruptcy,
                  winding up, liquidation, dissolution, becoming an insolvent
                  under administration (as defined in section 9 of the
                  Corporations Law), the appointment of an administrator and the
                  occurrence of anything analogous or having a substantially
                  similar effect to any of those conditions or matters under the
                  law of any applicable jurisdiction, and to the procedures,
                  circumstances and events which constitute any of those
                  conditions or matters;

         1.2.12   a reference to a matter being "TO THE KNOWLEDGE" of a person
                  means that the matter is to the best of the knowledge and
                  belief of that person after making reasonable enquiries in the
                  circumstances;

         1.2.13   a reference to a matter being written includes that matter
                  being in any mode of representing or reproducing words,
                  figures or symbols in written form; and

         1.2.14   all references to units of measurement, in this Agreement, are
                  references to the units of measurement defined in or for the
                  purposes of the National Measurement Act, 1960 (Commonwealth);

         1.2.15   gas measured for the purposes of this Agreement is to be
                  measured by reference to its Gross Heating Value and volume;
                  and

         1.2.16   a reference in this Agreement to a time or date is a reference
                  to the time or date in Brisbane, Australia.



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1.3      HEADINGS

         In this Agreement, headings are for convenience of reference only and
         do not affect interpretation.

1.4      BUSINESS DAY


         If the day on which any act, matter or thing is to be done under this
         Agreement is not a Business Day, that act, matter or thing:


         1.4.1    if it involves a payment other than a payment which is due on
                  demand, must be done on the preceding Business Day; and

         1.4.2    in all other cases, may be done on the next Business Day.


2        RELATIONSHIP OF THE PARTIES

2.1      SEPARATE AGREEMENT WITH THE SELLERS

         This Agreement shall be construed as a separate agreement between the
         Buyer and each Seller for the sale of that Seller's Ownership
         Percentage of the Contract Gas to be delivered to the Buyer.

2.2      SEVERAL LIABILITY

         The obligations and liability of each Seller under this Agreement are
         several and not joint nor joint and several.

2.3      PARTIES NOT RELEASED

         No Seller shall be responsible for the obligations of any other Seller
         under this Agreement. Default by a Seller under its separate agreement
         with the Buyer shall not release:

         (a)      any other Seller from any of its obligations to the Buyer, or

         (b)      the Buyer from any of its obligations to any other Seller.

2.4      COMMON STREAM

         Contract Gas delivered by the Sellers under this Agreement, may be
         tested, measured and delivered in a common stream, and each Seller
         shall be deemed to have delivered its Ownership Percentage of all
         Contract Gas delivered to the Buyer in accordance with this Agreement.


3.       TITLE TO CONTRACT GAS

         The Sellers shall have title to and be in control and possession of and
         shall assume all risk for the Contract Gas until it is delivered to
         Buyer at the Delivery Point when Buyer




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         shall take title to and be in control and possession of and shall
         assume all risk for the Contract Gas so delivered.


4.       DELIVERY

4.1      All Contract Gas to be delivered by the Sellers to the Buyer shall be
         delivered at the Delivery Point, where, the ownership of the Contract
         Gas will be transferred from the Sellers to Buyer.

4.2      The Sellers shall deliver Contract Gas to the Delivery Point at a
         pressure which meets the entry specifications of the Duke Queensland
         Gas Pipeline at the Delivery Point.

4.3      The Sellers shall use all reasonable endeavours to ensure that Contract
         Gas is delivered at uniform hourly rates during each Day.


5.       SPECIFICATIONS

5.1      If any Contract Gas delivered or likely to be tendered for delivery is
         Off-Specification Gas:

         5.1.1    the Sellers, as soon as practicable after becoming aware of
                  such non-conformity, shall notify Buyer of the non-conformity
                  and of its cause and probable duration, and shall take such
                  steps as are practicable to bring all Contract Gas tendered
                  thereafter for delivery into conformity with the
                  Specifications; and

         5.1.2    If Off-Specification Gas has been tendered for delivery but
                  not delivered, Buyer, being aware that the Contract Gas so
                  tendered is Off-Specification Gas, may:

                  5.1.2.1  refuse to accept all or part of such
                           Off-Specification Gas until the non-conformity has
                           been remedied;

                  5.1.2.2  take delivery of all or part of the Off-Specification
                           Gas in which case it shall be deemed to be Contract
                           Gas and shall be paid for at the Contract Price.


6.       QUANTITY AND PROCEDURES FOR THE SUPPLY OF CONTRACT GAS

6.1      CONTRACT QUANTITIES


         Subject to clause 5, the Sellers shall sell and deliver to Buyer and
         Buyer shall purchase and take delivery from Seller of Contract Gas
         including deliveries of Make up Gas previously paid for and to be
         debited to Buyer's Make up Gas account, on the following conditions:

         6.1.1    subject to clauses 6.2 and 6.3, the Maximum Daily Quantity
                  shall be as set out in Schedule 6;



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         6.1.2    the Sellers must use their reasonable endeavours, on each and
                  every Day, to make available for delivery to the Buyer , the
                  amount of Contract Gas nominated by the Buyer, provided that
                  no Seller shall be obliged to make available for delivery any
                  quantity of Gas in excess of its Ownership Percentage of the
                  amount of Contract Gas nominated by Buyer;

         6.1.3    on any Day Buyer has the right to nominate, at its sole
                  discretion, an amount of Contract Gas up to the Maximum Daily
                  Quantity;

         6.1.4    notwithstanding clause 6.1.3, in any Month, Buyer's minimum
                  obligation to take or pay for Contract Gas, in that Month,
                  shall be the Take or Pay Quantity and Buyer shall pay for such
                  amount whether taken or not.

6.2      REDUCTION OF MDQ BY BUYER

         6.2.1    Despite any other provisions of this Agreement and in addition
                  to any other right or remedy that Buyer may have under this
                  Agreement or otherwise, if during any Reconciliation Period
                  Sellers fail to deliver an amount of Contract Gas equal to or
                  greater than the aggregate of fifty (50) percent of the
                  Maximum Daily Quantity for each Day multiplied by the number
                  of Days in that Reconciliation Period, Buyer may, at its sole
                  discretion, reduce the Maximum Daily Quantity by giving one
                  (1) Month written notification of the reduction. Such notice
                  must be given within one (1) Month of the end of the
                  Reconciliation Period.

         6.2.2    The reduced Maximum Daily Quantity shall be not less than the
                  quantity calculated as follows;

                  Reduced Maximum Daily Quantity  =  M D Q * Reduction Factor

                  where

                  Reduction Factor = A / (0.5 * MDQ * B)

                  and

                  A = the aggregate quantity of Contract Gas made available for
                  delivery at the Delivery Point during the Reconciliation
                  Period.

                  B = the number of Days in the Reconciliation Period.

                  * = multiplied by.

                  / = divided by.

         6.2.3    Despite any other provisions of this Agreement and in addition
                  to any other right or remedy that Buyer may have under this
                  Agreement or otherwise, if, during any Reconciliation Period,
                  Sellers fail to deliver, an amount of Contract Gas equal to or
                  greater than forty (40) percent of the Maximum Daily Quantity,
                  adjusted for any quantities of Contract Gas not delivered
                  because of an event of




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                  Force Majeure, for more than eighteen (18) Days of that
                  Reconciliation Period, Buyer may, at its sole discretion,
                  reduce the Maximum Daily Quantity by giving one (1) Month
                  written notification of the reduction. Such notice must be
                  given within one (1) Month of the last of the eighteen (18)
                  Days.

                  The reduced Maximum Daily Quantity shall be not less than
                  eighty (80) percent of the Maximum Daily Quantity applying
                  during that Reconciliation Period.

         6.2.4    Despite any other provision of this Agreement and in addition
                  to any other right or remedy that the Buyer may have under
                  this Agreement or otherwise, if, during any period of one
                  calendar month, the Sellers fail to deliver an amount of
                  Contract Gas equal to or greater than forty (40) percent of
                  the Maximum Daily Quantity, adjusted for any quantity of
                  Contract Gas not delivered because of an event of Force
                  Majeure, for more than fourteen (14) Days, the Buyer may, at
                  its sole discretion, terminate this Agreement by giving seven
                  (7) Days notice in writing to the Sellers

         6.2.5    Pursuant to clauses 6.2.1, 6.2.2 and 6.2.3 the reduced amount,
                  being the Maximum Daily Quantity for the balance of the Term,
                  will take effect immediately upon receipt of such notification
                  by the Sellers and is subject to further reduction at the end
                  of each Reconciliation Period pursuant to this Agreement.

6.3      REDUCTION OF MDQ BY SELLERS

         6.3.1    Despite any other provisions of this Agreement and in addition
                  to any other right or remedy that Sellers may have under this
                  Agreement or otherwise, if during any Reconciliation Period
                  Buyer fails to take or pay for an amount of Contract Gas equal
                  to or greater than the aggregate of seventy (70) percent of
                  the Maximum Daily Quantity for each Day multiplied by the
                  number of Days in that Reconciliation Period, adjusted by
                  deducting all amounts of Contract Gas equal to any amount up
                  to the Maximum Daily Quantity that the Sellers have failed to
                  deliver to the Buyer in accordance with the Daily Nomination,
                  Sellers may, at their sole discretion, reduce the Maximum
                  Daily Quantity by giving one (1) Month written notification of
                  the reduction. Such notice must be given within one (1) Month
                  of the end of the Reconciliation Period.

         6.3.2    The reduced Maximum Daily Quantity shall be not less than the
                  quantity calculated as follows;

                  Reduced Maximum Daily Quantity  =  M D Q * Reduction Factor

                  where

                  Reduction Factor = A / (0.7 * MDQ * B)

                  and

                  A = the aggregate quantity of Contract Gas actually taken or
                  paid for without being taken during the Reconciliation Period



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                  B = the number of Days in the Reconciliation Period.

                  *     =  multiplied by.

                  /     =  divided by.

         6.3.3    Despite any other provisions of this Agreement and in addition
                  to any other right or remedy that Sellers may have under this
                  Agreement or otherwise, if during any Reconciliation Period,
                  Buyer fails to take or pay for without taking, an amount of
                  Contract Gas equal to or greater than forty (40) percent of
                  the Maximum Daily Quantity, adjusted by deducting all amounts
                  of Contract Gas equal to any amount up to forty (40) percent
                  of the Maximum Daily Quantity, that the Sellers have failed to
                  deliver, for more than eighteen (18) Days of that
                  Reconciliation Period, Sellers may, at their sole discretion,
                  reduce the Maximum Daily Quantity by giving one (1) Month
                  written notification of the reduction. Such notice must be
                  given within one (1) Month of the last of the eighteen (18)
                  Days.

                  The reduced Maximum Daily Quantity shall be not less than
                  eighty (80) percent of the Maximum Daily Quantity applying
                  during that Reconciliation Period.

         6.3.4    Pursuant to clauses 6.3.1, 6.3.2 and 6.3.3 the reduced amount,
                  being the Maximum Daily Quantity for the balance of the Term,
                  will take effect immediately upon receipt of such notification
                  by the Buyer and is subject to further reduction at the end of
                  each Reconciliation Period pursuant to this Agreement.

6.4      NOMINATIONS

         Subject to clause 6.1, the Daily and Monthly scheduling procedures for
         the delivery and receipt of Contract Gas shall be as follows:

         6.4.1    not later than five (5) Business Days before the end of the
                  Month prior to each Month of delivery, Buyer shall notify the
                  Sellers in writing of Buyer's estimates of the quantities of
                  Contract Gas which Buyer wishes to take on each Day of the
                  Month of delivery for that Month;

         6.4.2    not later than forty eight (48) hours after receipt of such
                  nomination, Sellers shall notify Buyer in writing of the
                  actual amount of Contract Gas to be delivered on each Day of
                  that Month;

         6.4.3    subject to clause 6.4.4, the quantity so nominated for each
                  Day pursuant to clause 6.4.1 shall form the Daily Nomination
                  for that Day of the Month of delivery in question;

         6.4.4    if Buyer wishes to change its Daily Nomination given pursuant
                  to clause 6.4.1, for any Day in the applicable Month, then it
                  may do so, and if it so chooses it must do so by notice given
                  to the Sellers before midday on the Day, one (1) Day before
                  the Day in question and the quantity then so nominated shall
                  be the Daily Nomination for that Day.



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6.5      MAKE UP GAS

         6.5.1    In any Month, after Buyer has purchased and taken delivery of
                  a quantity of Contract Gas equal to the Take or Pay Quantity ,
                  any further deliveries of Contract Gas during that Month shall
                  be deemed to be delivery of Make up Gas accumulated in respect
                  of prior Months to the extent that any such Make up Gas has
                  been accumulated, and if the aggregate of the quantities of
                  the further deliveries of Contract Gas are in excess of the
                  quantity of Make up Gas available, then Buyer shall pay for
                  any excess in accordance with Schedule 1.

         6.5.2    Buyer shall be entitled to take delivery of Make up Gas for a
                  period of twelve (12) months following the Termination Date.

                  All the terms and conditions of this Agreement, except clauses
                  9 and 10 shall apply in respect of such deliveries. Buyer
                  shall cease to have any rights to Make Up Gas not delivered by
                  the end of the period referred to in this clause 6.5.2.

         6.5.3    Deliveries of Make up Gas shall be at no additional charge to
                  Buyer.


6.6      FIELD FAILURE EVENT


         6.6.1    The Sellers acknowledge that, as the volumes of Gas (as shown
                  in Schedule 6) supplied under this Agreement increase, any
                  interruption to supply, except as permitted under Clause 11,
                  increases the difficulty for the Buyer to satisfy the Buyer's
                  obligations under its on-supply agreements.

         6.6.2    The Sellers will work together with the Buyer in good faith to
                  agree on measures to be implemented prior to the Delivery
                  Point to reduce the impact of variations of field gas output
                  and of failure of components of the field production,
                  collection and compression system.

         6.6.3    Without limiting clause 6.6.2, the Parties agree that the
                  following measures shall be undertaken by the Sellers to
                  achieve the above objectives:

                  6.6.3.1  Separation of, and if necessary, duplication of parts
                           of the gas gathering and collection system so that
                           failure of a single pipe system does not lead to loss
                           of entire Gas available for delivery;

                  6.6.3.2  Arrangement of the compressor station and the entry
                           of the gas collection system into the compressor
                           station to ensure that a single compressor failure
                           does not result in loss of ability to compress at
                           least 50% of the Gas supplied under this Agreement;

                  6.6.3.3  Maintenance, on site, of essential spare parts and
                           appropriately skilled personnel to address
                           contingency failures and repairs.

         6.6.4    The Buyer acknowledges that these measures will require the
                  Sellers to work with the Field Operator (where the Field
                  Operator is not one of the Sellers). The Sellers agree to use
                  best endeavours to ensure that any measures agreed between the
                  Parties are implemented by the Field Operator.



                                       14
<PAGE>   15

7.       DEDICATION OF RESERVES AND COMMITMENT TO DRILL

7.1      Subject to the terms and conditions of this Agreement, Sellers hereby
         agree to sell and deliver to Buyer at the Delivery Point all Contract
         Gas, up to the Maximum Daily Quantity, produced or saved from wells now
         or hereafter drilled within the Contract Area as described in Schedule
         4.

7.2      The Parties agree that Gas which is available from the Contract Area
         shall first be used to satisfy the Contract Gas requirements under the
         First Agreement. Any Seller under this Agreement which is not a party
         to the First Agreement, shall commit to satisfy the delivery
         requirements of this Agreement with priority over any other gas sales
         from the property attributable to that Seller's interest.

7.3      The Sellers will not offer to supply quantities of Gas which may become
         available from the Contract Area to persons other than the Buyer and
         purchasers who have in place gas sale and purchase agreements in
         existence at the date of this Agreement, without first satisfying the
         Contract Gas requirements under the First Agreement and this Agreement.

7.4      Sellers agree that they shall use their reasonable endeavours to ensure
         that a minimum of twenty (20) wells shall be drilled within the
         Contract Area during the first two (2) years of this Agreement.

7.5      Provided the Sellers shall have complied with their obligations under
         this Agreement, the rights or entitlements of the Buyer in the event of
         any failure by the Sellers to make available for delivery the amount of
         Contract Gas nominated by the Buyer shall be limited to those set out
         in this Agreement.


8.       MEASUREMENT OF VOLUMES AND REGULATION OF PRESSURES

8.1      The Sellers shall be responsible for installing, operating and
         maintaining the devices for measuring the Contract Gas or for arranging
         for the same to be done. The quantities of Contract Gas delivered by
         the Sellers will be measured and recorded by such measuring and
         recording devices, located immediately prior to the Delivery Point.

8.2      Any Party may, at its own risk and expense, install check measuring and
         recording devices, providing they do not interfere or influence the
         operation of the devices installed pursuant to clause 8.1 and providing
         that Party negotiates its own terms with the owner of the Duke
         Queensland Gas Pipeline.

8.3      Each Party or its agent shall, subject to it obtaining agreement from
         the owner of the Duke Queensland Gas Pipeline, have the right to be
         present to observe installation, reading, cleaning, changing,
         repairing, inspecting, calibrating or adjusting of the measuring and
         recording devices referred to in clause 8.1.

8.4      The Parties agree that the provisions of Schedule 3 will govern the
         measurement of Contract Gas for the purposes of this Agreement. If a
         Party is required to take action




                                       15

<PAGE>   16


         under an agreement which it has with another party to ensure that the
         requirements of Schedule 3 are met, that Party shall take all such
         action and do all such things as may be required to achieve that
         result.


9.       CONTRACT PRICE

9.1      The Contract Price at the Delivery Point, expressed in dollars per GJ,
         shall be calculated as in Schedule 1.

9.2      The Sellers shall be liable for all current and future taxes, imposts,
         royalties and liability incurred or levied, by or to the Federal
         Government or the Government of the State of Queensland, at or prior to
         the Delivery Point and Buyer shall be responsible for all current and
         future taxes, imposts and liability incurred or levied, by or to the
         Federal Government or the Government of the State of Queensland, after
         the Delivery Point. The Contract Price is inclusive of all such
         royalties, taxes and other sums as at the effective date of this
         Agreement.

9.3      GST

9.3.1    In this clause 9.3.1, the following definitions apply:

         9.3.1.1  GST means the goods and services tax as imposed by the GST Law
                  together with any related interest, penalties, fines or other
                  charge only to the extent they arise from the Buyer's failure
                  to pay when due.

         9.3.1.2  GST AMOUNT means any Payment (or the relevant part of that
                  Payment) multiplied by the appropriate rate of GST (currently
                  10%).

         9.3.1.3  GST LAW has the meaning given to that term in A New Tax System
                  (Goods and Services Tax) Act 1999, or, if that Act does not
                  exist for any reason, means any Act imposing or relating to
                  the imposition or administration of a goods and services tax
                  in Australia and any regulation made under that Act.

         9.3.1.4  INPUT TAX CREDIT has the meaning given to that term by the GST
                  Law.

         9.3.1.5  PAYMENT means any amount payable under or in connection with
                  this agreement including any amount payable by way of
                  indemnity, reimbursement or otherwise and includes the
                  provision of any non-monetary consideration.

         9.3.1.6  TAX INVOICE has the meaning given to that term by the GST Law.

         9.3.1.7  TAXABLE SUPPLY has the meaning given to that term by the GST
                  Law.


9.3.2    The parties agree that:

         9.3.2.1  all Payments have been calculated without regard to GST;




                                       16
<PAGE>   17

         9.3.2.2  each party will comply with its obligations under the Trade
                  Practices Act 1974 when calculating the amount of any Payment
                  and the amount of any relevant Payments will be adjusted
                  accordingly;

         9.3.2.3  if the whole or any part of any Payment is the consideration
                  for a Taxable Supply, the Buyer must pay to the Seller an
                  additional amount equal to the GST Amount, either concurrently
                  with that Payment or as otherwise agreed in writing;

         9.3.2.4  any reference to a cost or expense in this Agreement excludes
                  any amount in respect of GST forming part of the relevant cost
                  or expense when incurred by the relevant party for which that
                  party can claim an Input Tax Credit; and

         9.3.2.5  The payee will provide to the payer a Tax Invoice at the same
                  time as any GST Amount is payable

10.      BILLING AND METHOD OF PAYMENT

10.1     MONTHLY STATEMENT

         On or before the 10th day of each Month, the Sellers shall furnish to
         the Buyer a reconciliation and measurement statement in respect of the
         previous Month, or such part of that Month during which Contract Gas
         was made available by the Sellers, showing:

         (a)  the quantity of Contract Gas delivered;

         (b)  the quantity of Make up Gas delivered (if any);

         (c)  the price and total amount payable to each of the Sellers in
              respect of the Contract Gas delivered, together with any
              calculations necessary to establish the price and total amount to
              be paid; and

         (d)  the amount of any payment due each of the Sellers in respect of
              the Take or Pay Quantity not taken.

10.2     RECONCILIATION PERIOD STATEMENT

         On or before the tenth (10) Day of the Month following the expiry of
         each Reconciliation Period, the Sellers and the Buyer shall each
         furnish to the other Party a Reconciliation Period Statement showing
         for the previous Reconciliation Period all information necessary for
         either Party to exercise their rights under clauses 6.2, 6.3 and 10.4.

10.3     PAYMENT

         On or before the last Business Day of each Month, or within fourteen
         (14) Business Days after receipt of the monthly statement, whichever is
         the later, the Buyer shall pay to the Sellers the amount specified in
         the monthly statement. Any amounts due under this Agreement owed by
         Sellers to Buyer may be offset against any amounts invoiced by Sellers
         to Buyer.



                                       17

<PAGE>   18

         If any amount remains owing by the Sellers to the Buyer after such
         offset, Buyer shall issue an invoice to the Sellers by the tenth (10th)
         Day of the Month following the relevant Month and Sellers shall pay the
         invoice within fourteen (14) Business Days of receipt of invoice or by
         the last Day of the Month, whichever is the later.

         Unless otherwise agreed, all payments to be made pursuant to this
         Agreement shall be made by bank deposit to a bank account in Australia
         nominated in writing by the Sellers and the Buyer by no later than the
         due date for payment.

10.4     REBATE BY SELLERS TO BUYER

         Despite any other provision of this Agreement and in addition to any
         other remedy that Buyer may have under this Agreement or otherwise, if
         during any Reconciliation Period, Sellers fail to make available for
         delivery to the Buyer, an amount of Contract Gas equal to or greater
         than the aggregate quantity of fifty (50) percent of the Maximum Daily
         Quantity for each Day multiplied by the number of Days in that
         Reconciliation Period, Sellers shall rebate to the Buyer an amount
         equal to the quantity of Contract Gas taken or paid for but not taken
         during that Reconciliation Period multiplied by five (5) percent of the
         Contract Price.


10.5     INTEREST

         Payments made after the fourteenth Business Day following receipt of
         monthly statement will incur interest at the Interest Rate, with
         interest calculated from the twenty first Business Day following
         receipt of monthly statement or the twenty first Day of the Month
         following the relevant Month, whichever is the later.

10.6     DISPUTED STATEMENT

         In the event of a bona fide dispute in respect of any payment of any
         statement furnished by either Party under this clause, the Party that
         has an objection in regard to any portion of the amount of the invoice
         shall:

        (a) notify the other Party of the nature of the dispute and the amount
            in dispute;

        (b) make payment of any amount not in dispute in accordance with clause
            10.3.

        The Parties shall, upon request, each furnish to the other copies of all
        records relevant to the dispute. Any disputed amount which is
        subsequently found to be payable by or repayable shall be due and
        payable no later than 14 Days after resolution of the dispute together
        with interest on that amount calculated at the Interest Rate from the
        due date for payment.


11.     FORCE MAJEURE

11.1    DEFINITION

        11.1.1       For purposes of this Agreement, Force Majeure means any
                     event or circumstance not within the control of a Party and
                     which by the exercise of due diligence, that Party is not
                     reasonably able to prevent or overcome,




                                       18

<PAGE>   19


                    including without limiting the generality of the nature of
                    those events or circumstances:

                    (a)  acts of God, including without limitation, earthquakes,
                         floods, wash outs, landslides, lightning, storms and
                         the elements;

                    (b)  strikes, lockouts, bans, slowdowns or other industrial
                         disturbances except those that are directed exclusively
                         at the party seeking to rely on Force Majeure;

                    (c)  acts of enemy, wars, blockades or insurrections, riots
                         and civil disturbances, arrest and restraint of rulers
                         and peoples;

                    (d)  fire or explosion;

                    (e)  native title claims;

                    (f)  epidemic or quarantine;

                    (g)  order of any court or tribunal or the order, act, or
                         omission or failure to act of any government or
                         governmental authority having jurisdiction;

                    (h)  equipment breakdown, accident, breakages or accident to
                         machinery or pipelines, the necessity for making
                         repairs and/or alterations in machinery or pipelines
                         including machinery or pipelines of a third party
                         supplier to the Party seeking to rely on Force Majeure;
                         or

                    (i)  any other event which is not within the reasonable
                         control of the Party.

          11.1.2  It is acknowledged that the following matters will not
                  constitute Force Majeure under this Agreement:

                  11.1.2.1    lack of finances;

                  11.1.2.2    lack of funds;

                  11.1.2.3    inability to borrow funds;

                  11.1.2.4    Buyer's inability to economically use Contract Gas
                              purchased under this Agreement;  or

                  11.1.2.5    Sellers' inability to acquire Contract Gas
                              supplies on an economically viable basis.

11.2      CONSEQUENCES OF FORCE MAJEURE

          Subject to clause 11.3, non-performance as a result of Force Majeure
          by either Party of any obligation or condition required by this
          Agreement to be performed, other than the payment for Contract Gas
          already delivered and the payment of any debt or liability already
          incurred:




                                       19
<PAGE>   20

          11.2.1   shall be excused during the time and to the extent that such
                   performance by that Party is prevented, wholly or in part, by
                   Force Majeure; and

          11.2.2   shall not to that extent give rise to any liability to the
                   other Party for any direct, indirect, consequential or
                   special losses or damages of any kind arising out of, or in
                   any way connected with that non-performance.

11.3       NOTIFICATION AND DILIGENCE

           A Party which is, by reason of Force Majeure, unable to perform any
           obligation or condition required by this Agreement to be performed
           shall:

           11.3.1   notify the other Party as soon as possible giving:

                    11.3.1.1   reasonably full particulars of the event or
                               circumstance of Force Majeure;

                    11.3.1.2   the date of commencement of the event or
                               circumstance and an estimate of the period of
                               time required to enable it to resume full
                               performance of its obligations; and

                    11.3.1.3   where possible, the means proposed to be adopted
                               to remedy or abate the Force Majeure.

           11.3.2   use all reasonable diligence and employ all reasonable means
                    to remedy or abate the Force Majeure as expeditiously as
                    possible, but nothing in this clause 11 shall require a
                    Party to settle a strike, lockout, ban, slowdown or other
                    industrial disturbance, civil disobedience or native title
                    claim against its judgment, and it is acknowledged that
                    settlement of any such disturbance shall be entirely within
                    the discretion of the Party affected;

           11.3.3   resume performance as expeditiously as possible after
                    termination of the Force Majeure or after the Force Majeure
                    has abated to an extent which permits resumption of
                    performance;

           11.3.4   notify the other Party when the Force Majeure has terminated
                    or abated to an extent which permits resumption of
                    performance to occur; and

           11.3.5   provide the other Party with as much notice as is
                    practicable of the time and date when resumption of
                    performance will occur.

11.4       LIABILITY NOT RELIEVED

           Events of Force Majeure or circumstances affecting the performance
           under this Agreement by either the Sellers or Buyer, however, shall
           not relieve that Party of liability in the event, and to the extent
           that, its negligence caused or contributed to its failure to perform
           under this Agreement or in the event of its failure to use all
           reasonable endeavours to remedy the situation and to remove the event
           or circumstances giving rise to the Force Majeure in an adequate
           manner with all reasonable dispatch.



                                       20
<PAGE>   21

11.5     PROLONGED FORCE MAJEURE

         If a Party has invoked the provisions of this clause 11 and the same
         event of Force Majeure prevents or inhibits the performance of any
         obligation or condition required to be performed under this Agreement
         for a period of four (4) Months, then the Sellers and the Buyer shall
         consult in good faith to decide what action should be taken to carry
         out the intentions of this Agreement. If after a further one (1) Month
         the Parties are unable to agree that the Force Majeure can reasonably
         be resolved, then the Party not claiming to be prevented from
         performance by Force Majeure may terminate this Agreement upon the
         expiry of thirty (30) Days written notice to the other Party.


12.      TERM OF AGREEMENT

12.1     The effective date of this Agreement shall be the date of this
         Agreement.

12.2     This Agreement will remain in effect until the Termination Date.

12.3     Not more than four (4) years after the Commencement Date, Buyer will
         enter into discussions with the Sellers for an extension of supply
         period for up to five (5) years regarding pricing and supply terms.


13.      DEFAULT

13.1     If a Party defaults in performing its obligations under this Agreement,
         the non-defaulting Party may give the defaulting Party notice in
         writing specifying the default. Upon receipt of the notice, the
         defaulting Party shall have fifteen (15) Business Days or, in the event
         of a default to pay moneys due, seven (7) Business Days from the date
         of receipt of the default notice to rectify the default. If the default
         has not been rectified in such period the non-defaulting Party may
         suspend its obligations under this Agreement until the default is
         rectified or terminate this Agreement.


14.        ASSIGNMENT

14.1       ASSIGNMENT BY BUYER

           14.1.1   Buyer may only assign its rights and obligations under
                    this Agreement to any third party where:

                    (a)  in the reasonable opinion of the Sellers the assignee
                         is financially and technically capable of complying
                         with the obligations of the Buyer hereunder; and

                    (b)  the assignee first covenants in writing with the
                         Sellers to assume and be bound by the obligations of
                         the Buyer hereunder.

           14.1.2   Notwithstanding clause 14.1.1 Buyer may Dispose of the
                    whole or any part of its rights and obligations under
                    this Agreement to any Related Corporation. Such right of
                    assignment may only be exercised subject to prior
                    written notice to the Sellers.




                                       21
<PAGE>   22


14.2     ASSIGNMENT BY THE SELLERS

         Any Seller may assign to any third party its rights and obligations
         under this agreement or any part thereof provided that:

         (a)  in the reasonable opinion of the Buyer the assignee is
              financially and technically capable of complying with the
              obligations of the assignor hereunder; and

         (b)  the assignee first covenants in writing with the Buyer to assume
              and be bound by the obligations of the assignor hereunder.

15.      WARRANTIES

15.1.    The Sellers represent, warrant and guarantee to Buyer that:

         15.1.1. they have full corporate power and authority to enter into
                 this Agreement;

         15.1.2. their Ownership Percentage of the Contract Gas to be delivered
                 under this Agreement will, when delivered at the Delivery
                 Point, be free from liens, charges, encumbrances and adverse
                 claims which might prevent, impede or prejudice their rights to
                 sell and dispose of the Contract Gas, other than their existing
                 First Agreement with Allgas Energy Ltd.;

         15.1.3. to the knowledge of the Sellers, they have the capacity, during
                 each Contract Year, to deliver to Buyer, not less than the
                 Maximum Daily Quantity of Contract Gas in accordance with the
                 provisions of this Agreement; and

         15.1.4. they have adequate agreements to ensure their ability to
                 transport and deliver sufficient Contract Gas to the Delivery
                 Point for the Term.


15.2.    Buyer represents, warrants and guarantees to the Sellers that:

         15.2.1. it has adequate agreements to ensure its ability to transport
                 the Contract Gas from the Delivery Point for the Term; and

         15.2.2. it has full corporate power and authority to enter
                 into this Agreement.


16.      CONDITIONS PRECEDENT

16.1.    This Agreement shall not come into force until the satisfaction of the
         following conditions or their waiver at any time by the Buyer:

         16.1.1. the execution and coming into force of such gas transportation
                 agreements for a term at least equal to the Term of this
                 Agreement to effect transportation of the Contract Gas;

         16.1.2. the approval of the Board of the Buyer;



                                       22

<PAGE>   23


        16.1.3. the provision of information by the Sellers to the Buyer
                establishing to the Buyer's satisfaction that the Sellers (or
                their agent) have obtained a funding commitment and all
                regulatory approvals necessary to undertake a 20 well
                exploration programme on ATP526P to establish sufficient
                production as contemplated by this Agreement..

16.2.  As soon as practicable after the execution of this Agreement, Buyer will
       use reasonable endeavours to achieve the satisfaction of the conditions
       referred to in clause 16.1 and will advise the Sellers immediately upon
       satisfaction of any of the conditions.

16.3.  In the event that Buyer has not notified the Sellers that the conditions
       referred to in clause 16.1 are not either satisfied or waived within
       thirty Days of the signing of this Agreement, then either Party may
       terminate this Agreement by notice in writing.


17.    DAMAGES

       Notwithstanding what is contained in this Agreement, expressly or by
       implication, except in the event of a breach of the representation,
       warranties and guarantee in clause 15, neither the Sellers nor Buyer
       shall have any liability to the other whatsoever for loss of business or
       loss of profits, howsoever caused, arising out of or in connection with
       this Agreement.


18.    AUDITING

       Each Party has the right upon reasonable notice, at its sole expense and
       during normal working hours, to examine such of the records of the other
       Party as necessary to verify the accuracy of any invoice, statement,
       charge, notice or computation made pursuant to the stipulations of this
       Agreement. If any such examination reveals an inaccuracy in the invoice,
       the necessary adjustments in such invoice and the corresponding payments
       will be promptly made, provided that no adjustment will be made for any
       invoice or payment made after the lapse of one (1) year from the
       rendition thereof, and provided that this stipulation of the Contract
       survives any expiry or termination of this Contract for a period of one
       (1) year from the date of such expiry or termination for such invoice and
       payment adjustments.


19.    CONFIDENTIALITY

       The terms of this Agreement and all data and information relating to the
       sale and purchase of Gas pursuant to this Agreement shall be kept
       confidential and shall not be disclosed by a Party to any person without
       the prior written approval of the other Party except where disclosure is
       made by a Party:


       (a)    to its employees, independent contractors, advisers, lawyers and
              auditors for the purposes of this Agreement, and that Party has
              taken all precautions which are reasonably necessary to ensure
              that those persons to whom disclosure may be made under this
              clause shall keep the data and information confidential;

       (b)    as required by a Securities Commission having jurisdiction over
              that Party or over a Related Corporation of that Party, or by the
              rules of any Stock Exchange



                                       23

<PAGE>   24

              on which the shares of a Party, or a Related Corporation of that
              Party may then be listed;

       (c)    to the extent required by law or by the order of a court
              exercising competent jurisdiction to be disclosed by a Party, or
              by the Related Corporation of that Party referred to in
              paragraph (b);

       (d)    to a Related Corporation of the disclosing Party providing the
              disclosing Party assumes responsibility for maintaining the
              confidentiality of the data and information disclosed;

       (e)    to the extent that the data and information is already lawfully
              within the public domain;

       (f)    for the purpose of any litigation or arbitration proceedings which
              may arise from this Agreement;

       (g)    to a bank or other lending agency necessary in connection with the
              funding by a Party;

       (h)    to any employee or Minister of the State of Queensland provided
              that the fact that the information is confidential is communicated
              to that person and that person has agreed to keep that information
              confidential.

       If at any time the disclosing Party requests, the receiving Party must
       return, and procure that any of its Related Corporations return within
       seven days of such request, the confidential information to the
       disclosing Party as the disclosing Party directs. The obligations of the
       Parties under this clause shall be continuing obligations and shall
       continue to bind the Parties for a period of one year after the expiry of
       the term of this Contract.


20.    ENTIRE AGREEMENT

       This Agreement constitutes the entire agreement between the Parties as to
       the terms upon which the sales and purchase of Contract Gas takes place
       and supersedes all prior or contemporaneous understanding, agreement or
       prior warranties, oral or written with the exception of the existing
       First Agreement.


21.    CESSATION OF INDIVIDUAL CLAUSES

       If any clause or part of a clause of this Agreement ceases to be
       enforceable or is terminated by the Parties, such cessation or
       modification to this Agreement shall be binding on each Party unless
       agreed to in writing by both Parties.


22.    LAW AND DISPUTE RESOLUTION

22.1   JURISDICTION

       This Agreement shall be governed by the laws for the time being in force
       in the State of Queensland and, subject to the entirety of this clause
       22, the courts of that State and the courts hearing appeals therefrom
       shall have the exclusive jurisdiction in respect of any disputes arising
       out of or in connection with this Agreement.



                                       24
<PAGE>   25

22.2   DISPUTE RESOLUTION

       The Parties will attempt in good faith to resolve promptly any
       controversy or claim arising out of or relating to this Agreement by
       entering into negotiations in accordance with the following procedure
       before taking any legal proceedings in relation to that controversy or
       claim:

       (a)    the Chief Executive Officer (or a senior manager designated by the
              Chief Executive Officer) of each Party shall meet and attempt to
              resolve the controversy or claim;

       (b)    either Party may given Notice requesting a meeting under
              paragraph (a), which must be convened within seven (7) Days of the
              date of receipt of the Notice;

       (c)    the Parties may retain the non-binding services of an agreed
              mediator in an attempt to resolve the controversy or claim;

       (d)    if the controversy or claim has not been resolved within
              twenty-one (21) Days of the meeting held under paragraph (b),
              either Party may submit the controversy or claim to litigation.

22.3   CONTINUING OBLIGATION

       Neither the commencement nor conduct of mediation or litigation shall
       cause any interruption to the Parties' obligations under this Agreement
       or to the performance by the Parties of their respective obligations
       under this Agreement.


23.    AMENDMENTS

       No person, promise, agreement, warranty or guarantee other than those
       contained in this Agreement and no alteration, amendment or modification
       to this Agreement shall be binding on either Party unless agreed to in
       writing by both Parties.


24.    NOTIFICATION

24.1   GIVING OF NOTICES

       A notice, consent, approval, invoice or other communication under this
       Agreement shall be signed by or on behalf of the Party giving it,
       addressed to the Party to whom it is to be given and:

       24.1.1 delivered to that Party's address;

       24.1.2 sent by pre-paid mail to that Party's address; or

       24.1.3 transmitted by facsimile to that Party's address.

24.2   TIMING OF RECEIPT

       A Notice given to a Party in accordance with this clause 24 shall be
       treated as having been given and received:



                                       25
<PAGE>   26

       24.2.1 if delivered to a Party's address, on the day of delivery if a
              Business Day, otherwise on the next Business Day;

       24.2.2 if sent by pre-paid mail, on the third Business Day after posting,
              or if posting point is not in Australia, on the tenth Business Day
              after posting; and

       24.2.3 if transmitted by facsimile to a Party's address and a correct and
       complete transmission report is received, on the day of transmission if
       transmitted before 5.00 pm on a Business Day, otherwise on the next
       Business Day.

       Any notice required to be given to or by the Sellers shall be treated as
       having been given, if given as representative on behalf of the Sellers,
       to or by Tipperary Oil & Gas (Australia) Pty Ltd, or any other of the
       Sellers which the Sellers may from time to time give notice to Buyer.

24.3      ADDRESSES

       For the purpose of this clause 23 the address of a Party is the address
       set out below or another address of which that Party may from time to
       time give Notice to each other Party:

       (a)      For Buyer:

       Attention:        General Manager - Energy Trading

       Address:          Anzac Square Building
                         200 Adelaide St
                         Brisbane  QLD  4000

       Telephone:        +61-07- 3407 4000
       Facsimile:        +61-7- 3407 5665

       (b)      For Sellers:

       Attention:        President

       Address:          Suite 1550
                         633 Seventeenth Street
                         Denver, Colorado 80202

       Telephone:        +1- 303- 293 9379
       Facsimile:        +1- 303- 292 3428

       Any change of the above which either Party makes must be made known to
       the other Party in writing and as soon as reasonably practicable.



                                       26
<PAGE>   27


25  TERMINATION

25.1.  Either Party may terminate this Agreement by giving notice to the other,
       in the event of:

       25.1.1. the other committing an act of bankruptcy, ceasing to trade or
               going into receivership or liquidation (other than for the
               purposes of amalgamation or reconstruction); or

       25.1.2. the other being materially in breach of any of its obligations
               under this Agreement (other than a failure by the Sellers to
               deliver the nominated amount of Contract Gas) provided that
               notice has been given pursuant to clause 13.

25.2.  The termination of this Agreement, however occurring, shall not affect
       any rights or obligations that may have accrued to either Party prior to
       termination and shall not affect the terms of the Agreement that
       expressly or impliedly continue in force after termination.



                                       27
<PAGE>   28




26.      COUNTERPARTS

         This Agreement may be executed in any number of counterparts and all of
         those counterparts taken together constitute one and the same
         instrument.







Executed as an Agreement:


SIGNED for and on behalf of                               )
                                                          )
TIPPERARY OIL & GAS (AUSTRALIA) PTY. LTD ACN 077 536 871  )
                                                          )
by David L Bradshaw                                       )
                                                          )
the President and Chief Executive Officer                 )
                                                          )
thereof in the presence                                   )

of:  Kenneth L. Ancell



SIGNED for and on behalf of                               )
                                                          )
ENERGEX RETAIL PTY LTD ACN 078 849 055                    )
                                                          )
by J. T. Young                                            )
                                                          )
                                                          )
                                                          )
thereof in the presence                                   )
                                                          )
                                                          )
of:  Anthony Speed                                        )
                                                          )







                                       28
<PAGE>   29




                                   SCHEDULE 1

                                 CONTRACT PRICE

The base Contract Price for Contract Gas shall be [***] as at 1 January 2000
("Base Contract Price").

The "Base Date" shall be 1 January 2000.

The Contract Price for the period from the Commencement Date until 8.00 am on 1
January 2001 will be the base Contract Price and thereafter the Contract Price
will be adjusted at 8.00 am on 1 January in each Contract Year in accordance
with the following formula:

         Contract Price    =  BCP  *  [1 + 0.50 (CPI(n) - CPI(b)/CPI(b)]

where:

           BCP     =   Base Contract Price;

           CPI(n)  =   the CPI for the quarter ended the day before that
                       first day of January in respect of which the Contract
                       Price is being calculated

           CPI(b)  =   the base CPI being the CPI for the quarter ended
                       31 December, 1999.
and
           CPI     =   the Consumer Price Index as published by the
                       Australian Bureau of Statistics for the All Groups
                       Weighted Average of Eight Capital Cities or its
                       successor index in the event that this is modified.

Contract Price units are to be calculated to two (2) decimal places of a cent.
Where the third decimal place is a value of five (5) or greater the second
decimal unit is to be rounded up and where it is less than five (5) it is to be
rounded down.

Should the Consumer Price Index be abolished or abandoned, no longer published,
or its basis for calculation changed in a material respect then the Parties
agree to meet in good faith to agree upon a similar index as a substitute and,
failing agreement, the matter shall be referred to dispute resolution in
accordance with clause 22.3.

*** Text has been omitted and filed separately with the Securities and Exchange
    Commission. Confidential treatment has been requested under 17 C.F.R.
    section 240.24b-2.



                                       29
<PAGE>   30




                                   SCHEDULE 2

                                 SPECIFICATIONS

PART A

THE SPECIFICATIONS PRESCRIBED FROM TIME TO TIME UNDER THE REGULATIONS OF THE GAS
ACT, SUBJECT TO ANY EXEMPTIONS FROM COMPLIANCE GRANTED BY THE CHIEF GAS
EXAMINER. AS AT THE DATE OF THIS AGREEMENT THOSE SPECIFICATIONS ARE AS SET OUT
BELOW:

<TABLE>
<CAPTION>


ITEM
----
<S>                                      <C>
Odours, toxins, hazardous substances,     must be reasonably free from dust, gums, gum forming constituents, other
or solid matter etc                       liquid or solid matter which might cause injury to, or interference with,
                                          proper operation of pipeline regulators, meters, or other appliances
                                          through which it flows or which may interfere with the commercial
                                          utilisation of the Contract Gas by the Buyer

Water content                             must contain not more than 65 milligrams of water vapour per cubic metre

Hydrocarbon dewpoint                      must not exceed a hydrocarbon dew point of 10 degrees Celsius between
                                          the pressures of 1000 kPag and 10000 kPag

Oxygen                                    must not contain more than 0.2 per cent by volume of oxygen

Carbon dioxide                            must not contain more than 3.0 per cent by volume of carbon dioxide

Inerts                                    must not contain more than a combined total of 6.0 per cent by volume
                                          of inert gases

Hydrogen Sulphide                         must not contain more than 7 milligrams per cubic metre of hydrogen
                                          sulphide

Mercaptans                                must not contain more than 15 milligrams per cubic metre of mercaptans

Total Sulphur                             must not contain more than 50 milligrams per cubic metre of total
                                          sulphur

WOBBE Index                               shall have a WOBBE Index not less than 47 and not more than 52

Gross Heating Value                       if the Contract Gas contains more than 4.0 percent by volume of inerts,
                                          then the Contract Gas shall have a Gross Heating Value of not less than
                                          37.9 megajoules per cubic metre of Contract Gas and not more than 42.3
                                          megajoules per cubic metre of Contract Gas on a dry basis and if the
                                          Contract Gas contains less than or equal to 4.0 percent by volume of
                                          inerts, then the Contract Gas shall have a Gross Heating Value of not
                                          less than 35 megajoules per cubic metre of Contract Gas and not more
                                          than 43 megajoules per cubic metre of Contract Gas
</TABLE>



                                       30

<PAGE>   31




PART B
<TABLE>
<S>                                       <C>
Temperature                               Contract Gas must be at a temperature which is not less than zero
                                          (0) degrees Celsius and not higher than the greater of: (i) fifty
                                          (50) degrees Celsius, or (ii) the ambient temperature plus twelve
                                          (12) degrees Celsius but in any event not to exceed sixty (60)
                                          degrees Celsius
</TABLE>



                                       31
<PAGE>   32



                                   SCHEDULE 3

                            METERING METHOD SCHEDULE



The measuring equipment at the Delivery Point shall comply in all respects with
the technical requirements for such equipment as published from time to time by
owner of the Duke Queensland Gas Pipeline, which requirements shall nevertheless
be in accordance with good pipeline industry practice for this type of equipment
and conform to appropriate Australian and internationally recognised standards
and codes.

The latest editions of the following standards in the measurement of gas will be
applied:-

For gas flow measurement using orifice meters:

AGA - 3   "Orifice Metering of Natural Gas"

For gas flow measurement using turbine meters:

AGA - 7  "Measurement of Fuel Gas by Turbine Meters"

For the calculation of gas compressibility:

AGA - 8 "Natural Gas Density and Compressibility" or " AGA Manual for the
Determination of Super-compressibility (NX-19)", as appropriate.

Such standards shall be modified where necessary so as to ensure compliance with
"Australian Standard AS 1000 - 1979 (The International System of Units (SI) and
its Application)"




                                       32
<PAGE>   33



                                   SCHEDULE 4

                                 CONTRACT AREAS


Authority to Prospect 526P, granted 1 November 1992 comprising graticular blocks
shown on Block Identification Map CHAR as 347-348, 419-494, 563-566, 635-638,
707-710, 779-782, 851-854, 923-926, 995-998, 1067-1070, 1139-1142, 1283-1286,
1354-1358, 1426-1430, 1498-1502, 1570-1574 together with all petroleum leases
the subject of current or future application in relation thereto.



                                       33
<PAGE>   34




                                   SCHEDULE 5

                              OWNERSHIP PERCENTAGE

TIPPERARY OIL AND GAS (AUSTRALIA) PTY. LIMITED. having offices at Level 5,359
Queen Street, Brisbane, Queensland 4000.

Ownership of the contract areas:            58.203125%

Ownership of gas to be delivered:           100% *

*   Subject to the rights of the other parties to the Joint Operating Agreement
    dated May 15, 1992, by and between Tri-Star Petroleum Company, as Operator
    and Tipperary Corporation and others, as Non-Operators, including the right
    to participate in sales hereunder upon the terms and conditions of this Gas
    Supply Agreement and upon agreement to comply with the obligation of an
    assignee under clause 14.2 (b) of this Gas Supply Agreement and subject to
    the terms of the First Agreement.





                                       34
<PAGE>   35




                                   SCHEDULE 6

                             MAXIMUM DAILY QUANTITY

<TABLE>
<CAPTION>




                                                               Min MDQ during
                                                               "Field Failure          Total
Date                          Increase in MDQ                      Event"             Max  MDQ
----                          ---------------                  ---------------       ----------

<S>                          <C>                                  <C>                  <C>
Col 1                         Col 2                                Col 3                Col 4



Prior to 31 Dec 2000          Up to [1.5]TJ/d                     [0.75] TJ/d           1.5 TJ/d



Between 1 Jan 2001  &         Up to additional [2] TJ/d           [1.75] TJ/d           3.5 TJ/d
30 Jun 2001



Between 1 Jul 2001 &          Up to additional [2] TJ/d           [2.75] TJ/d           5.5 TJ/d
31 Dec 2001



Between 1 Jan 2002 &          Up to additional [3] TJ/d           [4.25] TJ/d           8.5 TJ/d
30 Jun 2002



From 1 Jul 2002 until         Up to additional                   [5-7.5] TJ/d         10-15 TJ/d
31 May 2005*                  [1.5-6.5] TJ/d
</TABLE>


*The Buyer shall advise the Sellers in writing no later than 1 July 2001 of the
MDQ which is to apply for the period from 1 July 2002 until 31 May 2005. The
Buyer shall be entitled to specify an MDQ of between 10 TJ/d and 15 TJ/d
inclusive for this period. Where the Buyer fails to advise the Sellers of the
MDQ for this period, then an MDQ of 10 TJ/d shall be deemed to apply.



                                       35