INDEX

GAS PURCHASE AGREEMENT

This Gas Purchase Agreement (“Agreement”) is made and entered into as of JANUARY 1, 2005, by and between ONEOK Texas Field Services, L. P., hereinafter referred to as “BUYER,” and W. O. OPERATING COMPANY, LTD., hereinafter, referred to as “SELLER”.

W I T N E S S E T H:

WHEREAS, SELLER owns and/or controls, natural; Gas produced from Wells on Lands or Leases from properties more particularly described in Exhibit “B” attached hereto, including the right to process and sell such Gas, which shall be delivered to BUYER; and

WHEREAS, BUYER desires to purchase and SELLER desires to sell said Gas to BUYER; and

NOW THEREFORE, BUYER and SELLER, in consideration of the mutual covenants, promises, and agreements contained herein and for other good and valuable consideration, do hereby agree as follows:

I.  BASIS OF COMPENSATION

1.1            Compensation.   The basis of compensation is set forth in Exhibit “A” attached hereto and included herein by this reference.

II.  TERM

2.1            Term.  This Agreement shall be effective JANUARY 1, 2005 (“Effective Date”), and shall continue until JANUARY 31, 2005 (“Primary Term”), and Month to Month thereafter until terminated, such termination to be effective at the end of said Primary Term or at any month thereafter by either party giving at least thirty (30) days prior written notice to the other party or to be effective as otherwise provided by this Agreement.

III.  DEDICATION, EXCLUSIVITY, INITIAL WELLS, AND SUBSEQUENT WELLS

3.1            Dedication.  SELLER hereby commits and dedicates to the performance of this Agreement and for the term hereof, all of its owned or controlled interest in Gas produced from all geological formations under the Lands and Leases and/or Wells described in Exhibit “B” attached hereto (“Dedicated Wells”), except for the following reservations which SELLER specifically reserves:

3.1.1      To use Gas produced from or under the Lands or Leases and/or Wells and used by SELLER for the development and operation of same; including, but not limited to, Gas used by SELLER in Gas lifting and pressure maintenance operations;

3.1.2      To use Gas which may be required to fulfill SELLER’s obligations to the lessors of said Leases and/or Wells for domestic fuel; and,

3.1.3      To use Gas used as fuel in the operation of SELLER’s compression, dehydration or treating facilities, if any, installed for the delivery of Gas hereunder.

3.2            Exclusivity.   Subject to the terms and conditions of this Agreement, SELLER hereby contracts exclusively with BUYER for the purchase of SELLER’s Gas and the right to process and extract Plant Products attributable to SELLER’s Gas.  SELLER further agrees to dedicate to BUYER and

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to the terms and conditions of this Agreement any interest in said Leases or Wells which (i) are acquired by SELLER, or (ii) are owned by SELLER but are no longer subject to the terms of any third-party agreement, subsequent to the Effective Date hereof.  Any transfer of SELLER’s interest in the Leases or Wells dedicated hereunder shall be subject to BUYER’s rights hereunder, and SELLER shall take action necessary to ensure that any such transfer is subject to BUYER’s rights hereunder.  BUYER reserves the right to reject any such additional dedication hereunder.

3.3            Initial Well(s).   SELLER agrees to proceed with due diligence to install or cause to be installed, ^: at its expense, all facilities at and upstream of each Receipt Point which are necessary to connect all Dedicated Wells completed for production as of the date of this Agreement to the existing gathering system.  All such facilities will be owned and operated by SELLER or its designee at its expense.

3.4            Subsequent Wells.   If the location of any Well (“Subsequent Well”) is within the dedication described in Exhibit “B” then SELLER shall notify BUYER in writing upon start of the Subsequent Well’s drilling.  After completion of the Subsequent Well, SELLER shall, within seven (7) days from the date of completion of such Subsequent Well, provide BUYER any and all relevant Well data (including, but not limited to, daily drilling reports, logs, completion reports, flow test, and gas analysis) (“Well Data”). BUYER shall have the right, but not the obligation, to connect such Subsequent Well to BUYER’s system at its expense.  If BUYER elects not to construct such facilities, or does not initiate right-of-way acquisition for such facilities within thirty (30) days after BUYER receives the Well Data, SELLER may construct, at its expense, the facilities necessary to deliver the Gas from such Subsequent Well to BUYER’s existing system.  If neither party connects such Subsequent Well, SELLER shall be entitled to a wellbore release from this agreement for production from the Subsequent Well only.

IV.  RESERVATIONS OF SELLER AND BUYER

4.1            SELLER’s Reservations.

4.1.1         To operate said Leases and/or Wells free from control by BUYER in such manner as SELLER, in SELLER’s sole discretion, may deem advisable, including, without limitation, the right to drill new Wells, to repair and rework old Wells, and to abandon any Well or surrender any Lease when no longer deemed to be capable of producing Gas in commercial paying quantities under normal methods of operation by SELLER.

4.1.2         To unitize or pool any of the Leases or portions thereof with other Leases, in such event SELLER’s interest in the unit and the unit Gas attributable to SELLER’s interest shall be subject to and SELLER agrees to take all action necessary to commit such unit Gas attributable to SELLER’s interest to this Agreement.

4.1.3         To retain all liquids and Condensate separated from the Gas by the use of typical volumetric (non-refrigerated) oil and Gas separators prior to the delivery of the Gas to BUYER at the Receipt Point(s) specified herein.

4.2            BUYER’s Reservations.

4.2.1         Processing Rights.   SELLER does hereby grant, assign, and convey to BUYER exclusive processing rights for the recovery of Plant Products for Gas delivered to BUYER for processing at the Receipt Point(s). SELLER shall not process the Gas or allow the Gas to be processed prior to receipt by BUYER hereunder for processing.

4.2.2         Condensate.   Condensate recovered by BUYER downstream of the Receipt Point(s) shall belong to BUYER.  Title to the Condensate shall pass to BUYER upon its recovery by BUYER and shall be free and clear of all liens, claims, and encumbrances created by,

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through or under SELLER.

4.2.3         Uneconomic.   At any time during the term of this Agreement, in the event purchasing of SELLER’s Gas from any Receipt Point becomes uneconomic, as determined in the sole discretion and judgment of BUYER, BUYER may (i) suspend receipt of Gas at that Receipt Point, (ii) terminate this Agreement or (iii) modify Exhibit “B” attached hereto to remove that Receipt Point.  In such event, BUYER shall give SELLER thirty (30) days written notice that purchasing of Gas made available by SELLER from a Receipt Point has become economically unfeasible and what action BUYER shall take. Removal of a Receipt Point constitutes a release of Dedication of the Well(s) behind that Receipt Point.

V.  QUALITY OF DELIVERED GAS

5.1            The Gas delivered at the Receipt Point(s) shall meet the quality specifications defined in Exhibit “C” attached hereto.

5.2            BUYER shall have the right to either (i) accept Gas that does not conform to such specifications and deduct from payment due SELLER BUYER’s standard fee(s) for treatment as determined from time to time, or (ii) refuse delivery of the nonconforming Gas.  If BUYER refuses delivery of non-conforming Gas and SELLER elects not to conform such Gas to the quality specifications set forth herein, this Agreement may be terminated with respect to such non-conforming Gas upon thirty (30) days prior notice.

5.3            BUYER’s acceptance of Gas that does not conform to quality specifications set forth herein will not constitute a waiver of SELLER’s obligation to conform to such specifications in the future, nor a waiver of BUYER’s right to refuse delivery of such nonconforming Gas at any time.

VI.   DELIVERY, COMPRESSION, PRESSURES, METER FEES, REBUILD AND ALTERATIONS

6.1            Delivery.   Gas shall be delivered hereunder at the Receipt Point(s) described in Exhibit “B” attached hereto and shall be at pressures sufficient to enter, but not to exceed, the maximum allowable pressure for BUYER’s gathering system at the Receipt Point(s).  SELLER shall provide equipment required to protect BUYER’s systems from receiving Gas at pressures that exceed the maximum allowable pressures.  BUYER will provide SELLER the maximum allowable pressure for specific Receipt Point(s).

6.2            Pressures.  Pressures calculated for stages of compression shall be volume-weighted pressures at the Receipt Point(s) for the Month as determined by BUYER.

6.3            Meter Fees.   In the event that the total metered volume from any one (1) receipt Point falls below an average of ten (10) MCF per day for any month, BUYER shall charge SELLER a meter Fee for each MCF delivered by or for the account of SELLER for that month.  The meter fee for each MCF delivered shall be determined by dividing a sum of Three Hundred Dollars ($300) by the total metered volume (MCF) for that month.  In the event the total metered volume is zero (0) the fee shall be Three Hundred Dollars ($300) multiplied by SELLER’s owned or controlled interest.

6.4            Rebuild and Alterations.   BUYER reserves the right, in its sole discretion, to alter, repair, maintain, expand or rebuild, without approval of SELLER, any portion of BUYER’s facilities.  SELLER shall make no alterations, additions or repairs to or on the facilities of BUYER.  SELLER agrees not to connect or cause the connection of any third-party well to BUYER’s facilities for any purpose without the express written consent of BUYER, such consent to be in

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BUYER’s sole discretion.  If this condition is breached by SELLER, BUYER shall have the right and option, notwithstanding any other provision of this Agreement, to terminate this Agreement immediately and without further obligation to SELLER.

VII.   DELIVERIES

7.1            Deliveries.   SELLER shall deliver all available Gas in such uniform hourly flows as is commercially practicable.  In the event SELLER anticipates a material increase or decrease in the flow of Gas at any Receipt Point, SELLER shall provide BUYER with reasonable advance notice of change.

VIII.   PAYMENT, ESCALATION OF FEES, EXAMINATION, INDEMNIFICATION, SUSPENSION, AND DEDUCTIONS

8.1            Payment.   BUYER shall, on the later of (i) the last day of the month or (ii) within ten (10) day’s of BUYER’s receipt of any necessary allocation statements, pay SELLER for the Gas delivered hereunder during the preceding month.  During any period BUYER purchases Gas from SELLER and other SELLER(s) delivered to any Receipt Point(s), SELLER shall furnish, or cause to be furnished, to BUYER on or before the fifteenth (15th) day of each calendar month, any necessary allocation statements containing data (including, but not limited to, quantity and BTU content) that BUYER may require to enable BUYER to make payments.  SELLER is to cooperate with other SELLER(s) delivering Gas at the Receipt Point(s) in order to appoint in writing a representative who, as their agent, is to furnish an allocation statement.  BUYER is entitled to rely conclusively on such allocation statement, and has a complete defense to any claim by SELLER for any sums due for Gas delivered by SELLER at the Receipt Point(s) during any period by showing that BUYER has made payment to SELLER for its share, as identified in such allocation statement, of the total quantity of Gas received by BUYER at the applicable Receipt Point(s) during the period in question (other than for measurement error as specified in the Article titled MEASUREMENT OF GAS VOLUME AND TESTING) . If any allocation statement is not furnished to BUYER by the fifteenth (15 ^th ) day of any month, the time that BUYER has to make payment for delivered Gas (without interest) is to be extended until the payment cycle which next follows the tenth (10 ^th ) day after BUYER’s receipt of the allocation statement.

8.2            Final Payment.   All payments under this Agreement will be final unless questioned by either party within two (2) years of the due date of a payment, and during this two (2) year period either party may audit all records, accounts, books and charts of the other party, upon reasonable advance notice and during normal office hours, to verify the accuracy of any statement, charge, computation or demand made.

8.3            Escalation of Fixed Fees.  The fixed fee charges contained herein, unless otherwise noted, shall be escalated annually beginning on the first (1 ^st ) anniversary of the Effective Date of this Agreement based on the GDP Implicit Price Deflator contained in the Gross Domestic Product, fourth quarter (final) report, published by the U.S. Department of Commerce,  Bureau of Economic analysis, “GDP Deflator” in March of each year for the previous year.  For purposes of escalating the fixed fee charges herein, the annual rate escalation percentage (“Escalator”) will be determined by BUYER each April 1 by calculating the percent of increase from the year preceding said previous year’s GDP Deflator and the previous year’s GDP Deflator.

8.4            Examination of Records.   Each party to this Agreement shall have the right, at any and all reasonable times during normal business hours, to examine the books and records of the other

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party, to the extent necessary to verify the accuracy of any statement, charge, computation, or demand made under or pursuant to this Agreement, and both parties shall keep al