EXHIBIT 10.18



                                                               December 16, 2003

                        5-YEAR REVOLVING CREDIT AGREEMENT




                                   dated as of




                                December 16, 2003


                                      among



                       PIONEER NATURAL RESOURCES COMPANY,


                                 as the Borrower



                              JPMORGAN CHASE BANK,
                             as Administrative Agent

                 JPMORGAN CHASE BANK and BANK OF AMERICA, N.A.,
                                as Issuing Banks


                                       and
                            The Lenders Party Hereto


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


                      WACHOVIA BANK, NATIONAL ASSOCIATION,
                              as Syndication Agent


        BANK OF AMERICA, N.A., BANK ONE, N.A., FLEET NATIONAL BANK, WELLS
                        FARGO BANK, NATIONAL ASSOCIATION,
                           as Co-Documentation Agents



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


         J.P. MORGAN SECURITIES INC. and WACHOVIA CAPITAL MARKETS, LLC,
                      as Co-Arrangers and Joint Bookrunners






                                                               December 16, 2003

                                TABLE OF CONTENTS


                                                                           Page:


ARTICLE I Definitions....................................................    1

      Section 1.01      Defined Terms....................................    1
      Section 1.02      Classification of Loans and Borrowings...........   17
      Section 1.03      Terms Generally..................................   17
      Section 1.04      Accounting Terms; GAAP...........................   18

ARTICLE II The Credits...................................................   18

      Section 2.01      Commitments......................................   18
      Section 2.02      Commitment Increase..............................   18
      Section 2.03      Revolving Loans and Borrowings...................   20
      Section 2.04      Requests for Revolving Borrowings................   20
      Section 2.05      Swingline Loans..................................   21
      Section 2.06      Letters of Credit................................   23
      Section 2.07      Funding of Borrowings............................   26
      Section 2.08      Interest Elections...............................   27
      Section 2.09      Termination and Reduction of Commitments.........   28
      Section 2.10      Repayment of Loans; Evidence of Debt.............   29
      Section 2.11      Prepayment of Loans..............................   30
      Section 2.12      Fees.............................................   30
      Section 2.13      Interest.........................................   31
      Section 2.14      Alternate Rate of Interest.......................   32
      Section 2.15      Increased Costs..................................   32
      Section 2.16      Break Funding Payments...........................   33
      Section 2.17      Taxes............................................   34
      Section 2.18      Payments Generally; Pro Rata Treatment;
                         Sharing of Set-offs.............................   35
      Section 2.19      Mitigation Obligations; Replacement of Lenders...   37

ARTICLE III Representations and Warranties...............................   38

      Section 3.01      Organization; Powers.............................   38
      Section 3.02      Authorization; Enforceability....................   38
      Section 3.03      Governmental Approvals; No Conflicts.............   38
      Section 3.04      Financial Condition; No Material Adverse Change..   38
      Section 3.05      Properties.......................................   39
      Section 3.06      Litigation and Environmental Matters.............   39
      Section 3.07      Compliance with Laws.............................   39
      Section 3.08      Investment and Holding Company Status............   39
      Section 3.09      Taxes............................................   39
      Section 3.10      ERISA............................................   39
      Section 3.11      Disclosure.......................................   40

ARTICLE IV Conditions....................................................   40

      Section 4.01      Effective Date...................................   40
      Section 4.02      Each Credit Event................................   41

                                       i




                                                               December 16, 2003


ARTICLE V Affirmative Covenants..........................................   41

      Section 5.01      Financial Statements and Other Information.......   41
      Section 5.02      Notices of Material Events.......................   43
      Section 5.03      Existence; Conduct of Business...................   43
      Section 5.04      Payment of Obligations...........................   43
      Section 5.05      Maintenance of Properties; Insurance.............   44
      Section 5.06      Books and Records; Inspection Rights.............   44
      Section 5.07      Compliance with Laws.............................   44
      Section 5.08      Use of Proceeds and Letters of Credit............   44
      Section 5.09      Operations.......................................   44

ARTICLE VI Negative Covenants............................................   44

      Section 6.01      Indebtedness.....................................   44
      Section 6.02      Liens............................................   45
      Section 6.03      Fundamental Changes..............................   45
      Section 6.04      Financial Covenants..............................   46
      Section 6.05      Investments, Loans, Advances, Guarantees and
                          Acquisitions...................................   46
      Section 6.06      Swap Agreements..................................   46
      Section 6.07      Transactions with Affiliates.....................   47
      Section 6.08      Restrictive Agreements...........................   47

ARTICLE VII Events of Default............................................   47


ARTICLE VIII The Administrative Agent....................................   50

      Section 8.01      Administrative Agent.............................   50
      Section 8.02      The Co-Arrangers, Joint Bookrunners, Syndication
                          Agent and Co-Documentation Agents..............   51

ARTICLE IX Miscellaneous.................................................   52

      Section 9.01      Notices..........................................   52
      Section 9.02      Waivers; Amendments..............................   53
      Section 9.03      Expenses; Indemnity; Damage Waiver...............   53
      Section 9.04      Successors and Assigns...........................   55
      Section 9.05      Survival.........................................   58
      Section 9.06      Counterparts; Integration; Effectiveness.........   58
      Section 9.07      Severability.....................................   58
      Section 9.08      Governing Law; Jurisdiction; Consent to
                          Service of Process.............................   59
      Section 9.09      WAIVER OF JURY TRIAL.............................   59
      Section 9.10      Headings.........................................   60
      Section 9.11      Confidentiality..................................   60
      Section 9.12      Interest Rate Limitation.........................   61
      Section 9.13      USA Patriot Act Notice...........................   61

Schedules:

Schedule 2.01     Commitments
Schedule 2.13     Swingline Loan Rate Calculation
Schedule 3.06     Disclosed Matters
Schedule 6.02     Liens
Schedule 6.08     Existing Restrictive Agreements


                                       ii



                                                               December 16, 2003


Exhibits:

Exhibit A         Form of Assignment and Assumption
Exhibit B         Notice of Commitment Increase
Exhibit C         Form of Opinion of Borrower's Counsel
Exhibit D         Form of Subsidiary Guaranty
Exhibit E         Form of Promissory Note



                                      iii





                                                               December 16, 2003


     5-Year  Revolving  Credit  Agreement  dated as of December 16, 2003,  among
Pioneer Natural  Resources  Company,  a Delaware  corporation,  as the Borrower,
JPMorgan Chase Bank, as  Administrative  Agent,  JPMorgan Chase Bank and Bank of
America,  N.A.,  as Issuing  Banks,  the Lenders party  hereto,  Wachovia  Bank,
National  Association,  as Syndication  Agent, Bank of America,  N.A., Bank One,
N.A.,  Fleet  National  Bank,  Wells  Fargo  Bank,  National   Association,   as
Co-Documentation  Agents,  and J.P. Morgan  Securities Inc. and Wachovia Capital
Markets, LLC, as Co-Arrangers and Joint Bookrunners.

     The parties hereto agree as follows:

                                   ARTICLE I
                                  DEFINITIONS

     Section 1.01 Defined Terms. As used in this Agreement,  the following terms
have the meanings specified below:

     "ABR",  when used in reference to any Loan or Borrowing,  refers to whether
such Loan, or the Loans  comprising  such Borrowing,  are bearing  interest at a
rate determined by reference to the Alternate Base Rate.

     "Adjusted LIBO Rate" means,  with respect to any  Eurodollar  Borrowing for
any Interest Period, an interest rate per annum (rounded upwards,  if necessary,
to the next  1/16 of 1%)  equal to (a) the LIBO  Rate for such  Interest  Period
multiplied by (b) the Statutory Reserve Rate.

     "Administrative  Agent"  means  JPMorgan  Chase  Bank,  in its  capacity as
administrative agent for the Lenders hereunder.

     "Administrative  Questionnaire" means an Administrative  Questionnaire in a
form supplied by the Administrative Agent.

     "Affiliate" means, with respect to a specified Person,  another Person that
directly,  or  indirectly  through  one or more  intermediaries,  Controls or is
Controlled by or is under common Control with the Person specified.

     "Agreement" means this 5-Year Revolving Credit  Agreement,  as the same may
be amended, modified, restated, or replaced from time to time.

     "Alternate  Base Rate"  means,  for any day, a rate per annum  equal to the
greater  of (a) the Prime Rate in effect on such day and (b) the  Federal  Funds
Effective Rate in effect on such day plus 1/2 of 1%. Any change in the Alternate
Base Rate due to a change in the Prime Rate or the Federal Funds  Effective Rate
shall be effective  from and including the effective  date of such change in the
Prime Rate or the Federal Funds Effective Rate, respectively.

     "Applicable  Percentage"  means, with respect to any Lender, the percentage
of the Commitments  represented by such Lender's Commitment.  If the Commitments
have terminated or expired, the Applicable Percentages shall be determined based
upon the Commitments most recently in effect, giving effect to any assignments.

                                       1




                                                               December 16, 2003


     "Applicable  Margin"  means,  for any day,  with respect to any  Eurodollar
Loan, or with respect to the commitment fees payable hereunder,  as the case may
be,  the  Applicable  Margin  per  annum  set  forth  below  under  the  caption
"Eurodollar Spread" or "Commitment Fee Rate", as the case may be, based upon the
ratings by Moody's and S&P,  respectively,  applicable on such date to the Index
Debt:

       ======================   =======================   =====================
         Index Debt Ratings       Commitment Fee Rate       Eurodollar Spread
       ----------------------   -----------------------   ---------------------
                                                 
             Category 1                 0.15 %                   0.625 %
             = Baa1/BBB+
       ----------------------   -----------------------   ---------------------
             Category 2                 0.20 %                   0.750 %
              Baa2/BBB
       ----------------------   -----------------------   ---------------------
             Category 3                 0.25 %                   1.000 %
              Baa3/BBB-
       ----------------------   -----------------------   ---------------------
             Category 4                 0.30 %                   1.250 %
               Ba1/BB+
       ----------------------   -----------------------   ---------------------
             Category 5                 0.40 %                   1.750 %
              = Ba2/BB
       ======================   =======================   =====================


     Applicable Margin for ABR Loans is zero percent (0%).

     For  purposes of the  foregoing,  if both Moody's and S&P shall not have in
effect a rating for the Index Debt  (other  than by reason of the  circumstances
referred to in the last sentence of this  definition),  then such agencies shall
be deemed to have established a rating in Category 5. If the ratings established
or deemed to have been  established  by Moody's and S&P for the Index Debt shall
fall within different  Categories,  the Applicable  Margin shall be based on the
higher  of the  two  ratings,  unless  one of the  two  ratings  is two or  more
Categories  lower than the other,  in which case the Applicable  Margin shall be
determined  by reference to the Category next above that of the lower of the two
ratings;  provided,  however,  that if only one of  Moody's  or S&P  shall  have
established  a  rating,  then  the  Applicable  Margin  shall be  determined  by
reference to such available rating. If the ratings established or deemed to have
been  established  by Moody's and S&P for the Index Debt shall be changed (other
than as a result  of a change in the  rating  system of  Moody's  or S&P),  such
change shall be  effective as of the date on which it is first  announced by the
applicable rating agency,  irrespective of when notice of such change shall have
been furnished by the Borrower to the Agent and the Lenders  pursuant to Section
5.01 or otherwise.  Each change in the Applicable  Margin shall apply during the
period  commencing on the  effective  date of such change and ending on the date
immediately  preceding the effective date of the next such change. If the rating
system of Moody's or S&P shall  change,  or if either such rating  agency  shall
cease to be in the business of rating corporate debt  obligations,  the Borrower
and the  Lenders  shall  negotiate  in good  faith to amend this  definition  to
reflect such changed  rating system or the  unavailability  of ratings from such
rating  agency  and,  pending  the  effectiveness  of any  such  amendment,  the
Applicable  Margin shall be determined by reference to the rating of such agency
most recently in effect prior to such change or cessation.

     "Approved Fund" has the meaning assigned to such term in Section 9.04.

                                       2




                                                               December 16, 2003


     "Assignment and Assumption" means an assignment and assumption entered into
by a Lender and an  assignee  (with the  consent of any party  whose  consent is
required by Section 9.04), and accepted by the Administrative Agent, in the form
of Exhibit A or any other form approved by the Administrative Agent.

     "Availability  Period"  means the period from and  including  the Effective
Date  to but  excluding  the  earlier  of the  Maturity  Date  and  the  date of
termination of the Commitments.

     "Board" means the Board of Governors of the Federal  Reserve  System of the
United States of America.

     "Borrower"  means  the  Pioneer  Natural  Resources   Company,  a  Delaware
corporation.

     "Borrowing"  means  Revolving  Loans of the same Type,  made,  converted or
continued on the same date and, in the case of Eurodollar  Loans,  as to which a
single  Interest  Period is in effect or Swingline  Loans,  as to which a single
Interest Period is in effect.

     "Borrowing  Request"  means  a  request  by the  Borrower  for a  Revolving
Borrowing in accordance with Section 2.04.

     "Business Day" means any day that is not a Saturday, Sunday or other day on
which  commercial  banks in New York City or Texas are authorized or required by
law to remain closed;  provided that,  when used in connection with a Eurodollar
Loan,  the term "Business Day" shall also exclude any day on which banks are not
open for dealings in dollar deposits in the London interbank market.

     "Capital  Lease  Obligations"  of any Person means the  obligations of such
Person to pay rent or other  amounts  under  any lease of (or other  arrangement
conveying the right to use) real or personal property, or a combination thereof,
which  obligations  are required to be  classified  and accounted for as capital
leases on a balance  sheet of such  Person  under  GAAP,  and the amount of such
obligations  shall be the  capitalized  amount thereof  determined in accordance
with GAAP.

     "Certifying Officer" has the meaning set forth in Section 5.01(c).

     "Change in Control"  means (a) the  acquisition  of ownership,  directly or
indirectly,  beneficially  or of  record,  by any  Person or group  (within  the
meaning of the  Securities  Exchange Act of 1934 and the rules of the Securities
and Exchange  Commission  thereunder as in effect on the date hereof), of Equity
Interests  representing  more than 35% of the  aggregate  ordinary  voting power
represented by the issued and outstanding  Equity Interests of the Borrower;  or
(b) occupation of a majority of the seats (other than vacant seats) on the board
of directors  of the  Borrower by Persons who were neither (i)  nominated by the
board of directors of the Borrower nor (ii) appointed by directors so nominated.

     "Change in Law" means (a) the adoption of any law, rule or regulation after
the date of this Agreement,  (b) any change in any law, rule or regulation or in
the  interpretation or application  thereof by any Governmental  Authority after
the date of this  Agreement or (c) compliance by any Lender or the Issuing Banks
(or, for purposes of Section 2.15(b), by any lending office of such Lender or by
such Lender's or the Issuing Banks' holding companies, if any) with any request,
guideline  or  directive  (whether  or not  having  the  force  of  law)  of any
Governmental Authority made or issued after the date of this Agreement.

                                       3



                                                               December 16, 2003


     "CI Lender" has the meaning set forth in Section 2.02(a).

     "Class", when used in reference to any Loan or Borrowing, refers to whether
such Loan,  or the Loans  comprising  such  Borrowing,  are  Revolving  Loans or
Swingline Loans.

     "Co-Arrangers"  means both J.P. Morgan Securities Inc. and Wachovia Capital
Markets, LLC.

     "Code"  means the Internal  Revenue  Code of 1986,  as amended from time to
time.

     "Commitment"  means,  with respect to each Lender,  the  commitment of such
Lender to make  Revolving  Loans and to  acquire  participations  in  Letters of
Credit and Swingline Loans  hereunder,  expressed as an amount  representing the
maximum  aggregate  amount of such Lender's Credit Exposure  hereunder,  as such
commitment  may be (a) increased from time to time pursuant to Section 2.02, (b)
reduced from time to time  pursuant to Section 2.09, or (c) reduced or increased
from time to time  pursuant  to  assignments  by or to such  Lender  pursuant to
Section 9.04.  The initial  amount of each  Lender's  Commitment is set forth on
Schedule 2.01, or in the Assignment and Assumption pursuant to which such Lender
shall have assumed its Commitment,  as applicable.  The initial aggregate amount
of the Lenders' Commitments is $700,000,000.

     "Commitment Increase" has the meaning set forth in Section 2.02(a).

     "Commitment  Increase  Effective Date" has the meaning set forth in Section
2.02(b).

     "Consolidated  EBITDAX"  means,  with  respect  to  the  Borrower  and  its
Restricted  Subsidiaries,  for any  period,  Consolidated  Net  Income  for that
period,  plus (a) to the extent included in determining  Consolidated Net Income
for that period,  (i) the aggregate amount of Consolidated  Interest Expense for
that period, (ii) the aggregate amount of letter of credit fees paid during that
period,  (iii) the aggregate amount of income tax expense for that period,  (iv)
non-cash  extraordinary  losses,  (v) losses on the disposition of assets,  (vi)
losses or charges under Statement of Financial Accounting Standards 133 (and any
statements  replacing,  modifying or superceding such statement)  resulting from
the net change in the Borrower's (or any Restricted Subsidiary's) mark-to-market
portfolio of commodity  price risk  management  activities and (vii) all amounts
attributable  to  depreciation,  depletion,  amortization,  and  other  non-cash
charges and  expenses  for that period and (viii)  exploration  and  abandonment
expenses,  minus (b) to the extent  included  in  determining  Consolidated  Net
Income for that  period,  (i)  non-cash  extraordinary  income (ii) gains on the
disposition  of assets and (iii)  non-cash  gains under  Statement  of Financial
Accounting Standard 133 (and any statements replacing,  modifying or superceding
such  statement)  resulting from the net change in Borrower's (or any Restricted
Subsidiary's)  mark-to-market  portfolio  of  commodity  price  risk  management
activities during that period,  in each case determined on a consolidated  basis
in accordance with GAAP and without duplication of amounts.

                                       4




                                                               December 16, 2003


     "Consolidated Interest Expense" means, with respect to the Borrower and its
Restricted  Subsidiaries on a consolidated  basis for any period, the sum of (i)
gross interest expense  (including all cash and accrued interest expense) of the
Borrower and its Restricted Subsidiaries for such period on a consolidated basis
in accordance with GAAP, including to the extent included in interest expense in
accordance with GAAP (x) the  amortization of debt discounts and (y) the portion
of any payments or accruals with respect to Capital Leases allocable to interest
expense  and  (ii)  capitalized  interest  of the  Borrower  and its  Restricted
Subsidiaries on a consolidated basis in accordance with GAAP.

     "Consolidated Net Income" means, for any period, net income of the Borrower
and its Restricted Subsidiaries determined on a consolidated basis in accordance
with GAAP.

     "Consolidated  Tangible Net Worth" means, at any date, (i) the Consolidated
shareholders' equity of Borrower and its Restricted Subsidiaries  (determined in
accordance with GAAP); less (ii) the amount of Consolidated intangible assets of
Borrower and its Restricted  Subsidiaries,  provided, that to the extent oil and
gas mineral leases are classified as intangible  assets under GAAP, for purposes
of this definition,  those assets will be treated as tangible assets; less (iii)
the other  comprehensive  income  component of  consolidated  shareholders'  net
equity of Borrower  and its  Restricted  Subsidiaries  attributable  to deferred
hedge gains;  plus (iv) the aggregate  amount of any non-cash  write downs under
Statements of Financial  Accounting  Standards  Nos. 19, 109, 142, and 144, (and
any  statements  replacing,  modifying  or  superceding  such  statement),  on a
Consolidated  basis, by Borrower and its Restricted  Subsidiaries after December
31, 2002,  net of  associated  taxes;  plus (v) the other  comprehensive  income
component  of  consolidated   shareholders'  net  equity  of  Borrower  and  its
Restricted Subsidiaries attributable to deferred hedge losses.

     "Control"  means the  possession,  directly or indirectly,  of the power to
direct or cause the direction of the management or policies of a Person, whether
through  the  ability to  exercise  voting  power,  by  contract  or  otherwise.
"Controlling" and "Controlled" have meanings correlative thereto.

     "Credit Exposure" means, with respect to any Lender at any time, the sum of
the outstanding  principal amount of such Lender's Loans and its LC Exposure and
Swingline Exposure at such time.

     "Default"  means  any  event or  condition  which  constitutes  an Event of
Default or which  upon  notice,  lapse of time or both  would,  unless  cured or
waived, become an Event of Default.

     "Disclosed  Matters"  means  the  actions,  suits and  proceedings  and the
environmental matters disclosed in Schedule 3.06.

     "dollars" or "$" refers to lawful money of the United States of America.

     "Effective  Date"  means  the date on which  the  conditions  specified  in
Section 4.01 are satisfied (or waived in accordance with Section 9.02).

     "Environmental Laws" means all laws, rules, regulations, codes, ordinances,
orders, decrees, judgments,  injunctions,  notices or binding agreements issued,
promulgated or entered into by any Governmental  Authority,  relating in any way
to the  environment,  preservation  or  reclamation  of natural  resources,  the
management, release or threatened release of any Hazardous Material.

                                       5




                                                               December 16, 2003


     "Environmental  Liability"  means any  liability,  contingent  or otherwise
(including any liability for damages, costs of environmental remediation, fines,
penalties  or  indemnities),  of the  Borrower  or any  Subsidiary  directly  or
indirectly  resulting from or based upon (a) violation of any Environmental Law,
(b)  the  generation,  use,  handling,  transportation,  storage,  treatment  or
disposal of any Hazardous  Materials,  (c) exposure to any Hazardous  Materials,
(d) the  release or  threatened  release  of any  Hazardous  Materials  into the
environment  or (e) any  contract,  agreement  or other  consensual  arrangement
pursuant to which  liability  is assumed or imposed  with  respect to any of the
foregoing.

     "Equity  Interests" means shares of capital stock,  partnership  interests,
membership  interests in a limited liability company,  beneficial interests in a
trust or other equity ownership interests in a Person, and any warrants, options
or other  rights  entitling  the holder  thereof to purchase or acquire any such
equity interest.

     "ERISA"  means the Employee  Retirement  Income  Security  Act of 1974,  as
amended from time to time.

     "ERISA Affiliate" means any trade or business (whether or not incorporated)
that, together with the Borrower,  is treated as a single employer under Section
414(b) or (c) of the Code or,  solely for  purposes  of Section 302 of ERISA and
Section 412 of the Code,  is treated as a single  employer  under Section 414 of
the Code.

     "ERISA Event" means (a) any "reportable  event", as defined in Section 4043
of ERISA or the regulations issued thereunder with respect to a Plan (other than
an event for which the 30-day notice period is waived);  (b) the existence  with
respect  to any Plan of an  "accumulated  funding  deficiency"  (as  defined  in
Section 412 of the Code or Section 302 of ERISA), whether or not waived; (c) the
filing  pursuant to Section  412(d) of the Code or Section 303(d) of ERISA of an
application  for a waiver of the minimum  funding  standard  with respect to any
Plan; (d) the  incurrence by the Borrower or any of its ERISA  Affiliates of any
liability  under Title IV of ERISA with respect to the  termination of any Plan;
(e) the receipt by the Borrower or any ERISA  Affiliate  from the PBGC or a plan
administrator  of any notice  relating to an intention to terminate  any Plan or
Plans or to appoint a trustee to administer  any Plan; (f) the incurrence by the
Borrower or any of its ERISA  Affiliates  of any  liability  with respect to the
withdrawal or partial withdrawal from any Plan or Multiemployer Plan; or (g) the
receipt by the Borrower or any ERISA Affiliate of any notice,  or the receipt by
any  Multiemployer  Plan from the Borrower or any ERISA Affiliate of any notice,
concerning  the  imposition of Withdrawal  Liability or a  determination  that a
Multiemployer  Plan is, or is expected to be,  insolvent  or in  reorganization,
within the meaning of Title IV of ERISA.

     "Eurodollar",  when used in reference to any Loan or  Borrowing,  refers to
whether such Loan, or the Loans comprising such Borrowing,  are bearing interest
at a rate determined by reference to the Adjusted LIBO Rate.

                                       6





                                                               December 16, 2003

     "Event of Default" has the meaning set forth in Article VII.

     "Excluded  Taxes"  means,  with respect to the  Administrative  Agent,  any
Lender, the Issuing Banks or any other recipient of any payment to be made by or
on account of any obligation of the Borrower hereunder,  (a) income or franchise
taxes by the United States of America,  or by the jurisdiction under the laws of
which such  recipient is organized or in which its  principal  office is located
or,  in the case of any  Lender,  in which  its  applicable  lending  office  is
located, (b) any branch profits taxes imposed by the United States of America or
any  similar  tax  imposed by any other  jurisdiction  in which the  Borrower is
located and (c) in the case of a Foreign Lender (other than an assignee pursuant
to a request by the Borrower under Section 2.19(b),  any withholding tax that is
imposed  on  amounts  payable to such  Foreign  Lender at the time such  Foreign
Lender  becomes  a party  to  this  Agreement  whether  upon  execution  or upon
assignment  (or  designates  a new lending  office) or is  attributable  to such
Foreign Lender's  failure to comply with Section  2.17(e),  except to the extent
that such Foreign Lender (or its assignor,  if any) was entitled, at the time of
designation  of a new  lending  office (or  assignment),  to receive  additional
amounts  from the  Borrower  with  respect to such  withholding  tax pursuant to
Section 2.17(a).

     "Executive Officer" means any Financial Officer,  executive vice president,
officer  ranking above an executive  vice  president and any officer that is the
functional equivalent of the foregoing.

     "Existing Credit Agreement" means that certain Credit  Agreement,  dated as
of May 31, 2000, among the Borrower,  Bank of America,  N.A., as  Administrative
Agent, Credit Suisse First Boston, as Documentation Agent, Chase Manhattan Bank,
as Syndication Agent, and the lenders parties thereto.

     "Existing  Letters of Credit"  means the  Letters  of Credit  described  on
Schedule  1.01 that were  issued by Bank of  America,  N.A.  under the  Existing
Credit  Agreement and that shall be  transferred to and deemed issued under this
Agreement,  as such  Letters of Credit  may be  renewed or amended  from time to
time.

     "Federal Funds  Effective  Rate" means,  for any day, the weighted  average
(rounded  upwards,  if  necessary,  to the  next  1/100  of 1%) of the  rates on
overnight Federal funds  transactions with members of the Federal Reserve System
arranged by Federal funds brokers,  as published on the next succeeding Business
Day by the  Federal  Reserve  Bank  of New  York,  or,  if  such  rate is not so
published for any day that is a Business Day, the average (rounded  upwards,  if
necessary,  to the  next  1/100 of 1%) of the  quotations  for such day for such
transactions  received  by the  Administrative  Agent from three  Federal  funds
brokers of recognized standing selected by it.

     "Financial  Officer" means, with respect to any Person, the chief financial
officer,  principal accounting officer,  treasurer or controller of such Person.
The  term  "Financial  Officer"  without  reference  to a  Person  shall  mean a
Financial Officer of the Borrower.

     "Foreign  Lender"  means any Lender that is  organized  under the laws of a
jurisdiction  other than that in which the Borrower is located.  For purposes of
this  definition,  the United  States of  America,  each State  thereof  and the
District of Columbia shall be deemed to constitute a single jurisdiction.

                                       7




                                                               December 16, 2003


     "GAAP" means generally accepted accounting  principles in the United States
of America.

     "Governmental  Authority"  means the  government  of the  United  States of
America, any other nation or any political subdivision thereof, whether state or
local,  and any agency,  authority,  instrumentality,  regulatory  body,  court,
central  bank or  other  entity  exercising  executive,  legislative,  judicial,
taxing,  regulatory  or  administrative  powers or functions of or pertaining to
government.

     "Guarantee"  of or by any Person (the  "guarantor")  means any  obligation,
contingent or otherwise,  of the guarantor  guaranteeing  or having the economic
effect of guaranteeing  any Indebtedness or other obligation of any other Person
(the  "primary  obligor") in any manner,  whether  directly or  indirectly,  and
including any obligation of the guarantor,  direct or indirect,  (a) to purchase
or pay (or  advance  or  supply  funds  for the  purchase  or  payment  of) such
Indebtedness  or other  obligation or to purchase (or to advance or supply funds
for the purchase of) any  security for the payment  thereof,  (b) to purchase or
lease property,  securities or services for the purpose of assuring the owner of
such Indebtedness or other obligation of the payment thereof, or (c) to maintain
working capital,  equity capital or any other financial  statement  condition or
liquidity of the primary obligor so as to enable the primary obligor to pay such
Indebtedness or other  obligation,  provided,  that the term Guarantee shall not
include  endorsements  for  collection  or  deposit  in the  ordinary  course of
business.

     "Hazardous  Materials"  means all  explosive or  radioactive  substances or
wastes  and all  hazardous  or toxic  substances,  wastes  or other  pollutants,
including  petroleum or petroleum  distillates,  asbestos or asbestos containing
materials,  polychlorinated  biphenyls,  radon gas, infectious or medical wastes
and all other  substances  or wastes of any  nature  regulated  pursuant  to any
Environmental Law.

     "Highest  Lawful  Rate" means,  with  respect to each  Lender,  the maximum
nonusurious  interest rate, if any, that at any time or from time to time may be
contracted for, taken,  reserved charged or received on the  Indebtedness  under
laws  applicable  to such Lender which are presently in effect or, to the extent
allowed by law, under such  applicable laws which may hereafter be in effect and
which allow a higher  maximum  nonusurious  interest rate than  applicable  laws
allow as of the date hereof.

     "Hydrocarbon Interests" means all rights, titles, interests and estates now
owned or hereafter  acquired in and to oil and gas leases,  oil, gas and mineral
leases,  or other  liquid or gaseous  hydrocarbon  leases,  mineral fee or lease
interests,  farm-outs,  overriding  royalty  and royalty  interests,  net profit
interests,  oil  payments,  production  payment  interests  and similar  mineral
interests, including any reserved or residual interest of whatever nature.

     "Hydrocarbons"  means oil, gas,  casinghead  gas,  condensate,  distillate,
liquid  hydrocarbons,  gaseous  hydrocarbons,  all products refined,  separated,
settled and dehydrated therefrom and all products refined therefrom,  including,
without limitation, kerosene, liquefied petroleum gas, refined lubricating oils,
diesel fuel,  drip  gasoline,  natural  gasoline,  helium,  sulfur and all other
minerals.

                                       8


<PAGE<

                                                               December 16, 2003


     "Indebtedness"  of  any  Person  means,   without   duplication,   (a)  all
obligations  of such Person for  borrowed  money,  (b) all  obligations  of such
Person evidenced by bonds,  debentures,  notes or similar  instruments,  (c) all
obligations of such Person in respect of the deferred purchase price of property
or services (other than customary  payment terms taken in the ordinary course of
business), (d) all Indebtedness of others secured by (or for which the holder of
such Indebtedness has an existing right,  contingent or otherwise, to be secured
by) any Lien on property  owned or acquired by such  Person,  whether or not the
Indebtedness secured thereby has been assumed limited,  however to the lesser of
(1) the amount of its liability or (2) the book value of such property,  (e) all
Guarantees  by such Person of  Indebtedness  of others,  (f) all  Capital  Lease
Obligations of such Person,  (g) all  obligations,  contingent or otherwise,  of
such  Person as an account  party in  respect  of  letters  of  credit,  (h) all
obligations,  contingent  or  otherwise,  of such  Person in respect of bankers'
acceptances,  (i) the amount of deferred revenue  attributed to any forward sale
of production  for which such Person has received  payment in advance other than
on  ordinary  trade  terms,  (j) all  obligations  of such  Person in respect of
synthetic  leases and (k) the  undischarged  balance of any  production  payment
created by such  Person or for the  creation  of which such  Person  directly or
indirectly  received  payment.  The Indebtedness of any Person shall include the
Indebtedness of any other entity (including any partnership in which such Person
is a general  partner) to the extent such Person is liable  therefor as a result
of such Person's  ownership  interest in or other relationship with such entity,
except to the extent the terms of such Indebtedness  provide that such Person is
not liable therefor.

     "Indemnified Taxes" means Taxes other than Excluded Taxes.

     "Index Debt" means senior,  unsecured,  long-term indebtedness for borrowed
money of the Borrower  that is not  guaranteed  by any other Person except for a
Subsidiary Guarantor or subject to any other credit enhancement;  provided, that
if the  Borrower  does not have any such  indebtedness,  Index Debt shall be the
indebtedness under this Agreement.

     "Interest  Election  Request" means a request by the Borrower to convert or
continue a Borrowing in accordance with Section 2.08.

     "Interest  Payment  Date" means (a) with respect to any ABR Loan,  the last
day of each  March,  June,  September  and  December,  (b) with  respect  to any
Eurodollar Loan, the last day of the Interest Period applicable to the Borrowing
of which such Loan is a part and, in the case of a Eurodollar  Borrowing with an
Interest Period of more than three months' duration,  each day prior to the last
day of such Interest  Period that occurs at intervals of three months'  duration
after  the  first  day of such  Interest  Period  and (c)  with  respect  to any
Swingline Loan, the first day of each calendar month,  unless such day shall not
be a Business Day, in which case the next succeeding Business Day.

     "Interest  Period"  means  (a) with  respect  to any  Eurodollar  Revolving
Borrowing, the period commencing on the date of such Borrowing and ending on the
numerically  corresponding  day in the calendar month that is one, two, three or
six months or,  with the  consent of the  Administrative  Agent,  nine or twelve
months  thereafter,  as the  Borrower  may  elect,  and (b) with  respect to any

                                       9



                                                               December 16, 2003


Swingline  Loan, the period  commencing on the date of such Borrowing and ending
on the date  specified in Section  2.10(a);  provided,  that (i) if any Interest
Period would end on a day other than a Business Day, such Interest  Period shall
be  extended  to the  next  succeeding  Business  Day  unless,  in the case of a
Eurodollar  Revolving  Borrowing only,  such next succeeding  Business Day would
fall in the next calendar month, in which case such Interest Period shall end on
the next  preceding  Business Day and (ii) any Interest  Period  pertaining to a
Eurodollar  Revolving  Borrowing  that  commences on the last  Business Day of a
calendar month (or on a day for which there is no numerically  corresponding day
in the  last  calendar  month of such  Interest  Period)  shall  end on the last
Business Day of the last calendar  month of such Interest  Period.  For purposes
hereof,  the date of a  Borrowing  initially  shall  be the  date on which  such
Borrowing is made and, in the case of a Revolving Borrowing, thereafter shall be
the  effective  date of the  most  recent  conversion  or  continuation  of such
Borrowing.

     "Investment  Grade Date" means the first date on which the Borrower's Index
Debt rating is BBB- or better by S&P's or Baa3 or better by Moody's,  unless one
of the two  ratings  is two or more  categories  lower  than the  other  and the
category that is one above the lower rating is not BBB- or Baa3 or better.

     "Issuing  Bank" means JPMorgan Chase Bank, in its capacity as the issuer of
Letters of Credit hereunder,  and its successors in such capacity as provided in
Section  2.06(i).  The Issuing Bank may, in its  discretion,  arrange for one or
more Letters of Credit to be issued by  Affiliates of the Issuing Bank, in which
case the term  "Issuing  Bank" shall  include  such  Affiliate  with  respect to
Letters of Credit issued by such Affiliate.  Bank of America, N.A. shall also be
an Issuing Bank as to Existing Letters of Credit.

     "LC  Disbursement"  means a payment made by an Issuing  Bank  pursuant to a
Letter of Credit.

     "LC Exposure"  means,  at any time,  the sum of (a) the  aggregate  undrawn
amount of all outstanding  Letters of Credit at such time plus (b) the aggregate
amount of all LC Disbursements that have not yet been reimbursed by or on behalf
of the Borrower at such time. The LC Exposure of any Lender at any time shall be
its Applicable Percentage of the total LC Exposure at such time.

     "Lenders"  means the Persons  listed on Schedule  2.01 and any other Person
that shall have become a party hereto pursuant to Section 2.02 or pursuant to an
Assignment and Assumption,  other than any such Person that ceases to be a party
hereto  pursuant to an Assignment and Assumption.  Unless the context  otherwise
requires, the term "Lenders" includes the Swingline Lenders.

     "Letter  of  Credit"  means any letter of credit  issued  pursuant  to this
Agreement.

     "LIBO Rate" means, with respect to any Eurodollar  Revolving  Borrowing for
any  Interest  Period,  the rate  appearing on Page 3750 of the Dow Jones Market
Service  (or on any  successor  or  substitute  page  of  such  Service,  or any
successor  to  or  substitute  for  such  Service,   providing  rate  quotations
comparable  to  those  currently  provided  on such  page of  such  Service,  as
determined  by the  Administrative  Agent  from  time to time  for  purposes  of
providing  quotations of interest  rates  applicable  to dollar  deposits in the
London interbank market) at approximately  11:00 a.m., London time, two Business
Days prior to the commencement of such Interest  Period,  as the rate for dollar

                                       10




                                                               December 16, 2003



deposits with a maturity  comparable to such Interest Period.  In the event that
such rate is not  available  at such time for any  reason,  then the "LIBO Rate"
with respect to such Eurodollar  Borrowing for such Interest Period shall be the
rate at which dollar  deposits of  $5,000,000  and for a maturity  comparable to
such  Interest  Period  are  offered  by  the  principal  London  office  of the
Administrative  Agent in  immediately  available  funds in the London  interbank
market at approximately  11:00 a.m., London time, two Business Days prior to the
commencement of such Interest Period.

     "Lien" means,  with respect to any asset, (a) any mortgage,  deed of trust,
lien,  pledge,  hypothecation,  or security interest in, on or of such asset, or
any other  charge or  encumbrance  on any such asset to secure  Indebtedness  or
liabilities,  but excluding any right to netting or setoff (b) the interest of a
vendor or a lessor under any conditional sale agreement,  capital lease or title
retention  agreement  (or any  financing  lease  having  substantially  the same
economic  effect as any of the foregoing)  relating to such asset and (c) in the
case of securities,  any purchase option, call or similar right of a third party
with respect to such securities.

     "Loan Documents" means this Agreement and the Subsidiary Guaranties.

     "Loans"  means the loans made by the  Lenders to the  Borrower  pursuant to
this Agreement.

     "Material  Adverse  Effect"  means a  material  adverse  effect  on (a) the
business,  assets,  operations,  or financial  condition of the Borrower and the
Restricted Subsidiaries taken as a whole, (b) the ability of the Borrower or any
Subsidiary  Guarantor to perform any of its obligations under this Agreement and
any other  Loan  Document  or (c) the  rights of or  benefits  available  to the
Lenders under this Agreement and any other Loan Document.

     "Material  Indebtedness"  means  Indebtedness  (other  than the  Loans  and
Letters of Credit), or obligations in respect of one or more Swap Agreements, of
any one or more of the Borrower and its  Subsidiaries in an aggregate  principal
amount exceeding $75,000,000. For purposes of determining Material Indebtedness,
the "principal  amount" of the  obligations of the Borrower or any Subsidiary in
respect of any Swap Agreement at any time shall be the maximum  aggregate amount
(giving effect to any netting  agreements)  that the Borrower or such Subsidiary
would be required to pay if such Swap Agreement were terminated at such time.

     "Maturity Date" means December 16, 2008.

     "Mid-Investment  Grade Date"  means the first date on which the  Borrower's
Index Debt rating is BBB or better by S&P's or Baa2 or better by Moody's, unless
one of the two  ratings is two or more  categories  lower than the other and the
category that is one above the lower rating is not BBB or Baa2 or better.

     "Moody's" means Moody's Investors Service, Inc.

     "Multiemployer  Plan"  means a  multiemployer  plan as  defined  in Section
4001(a)(3) of ERISA.

                                       11




                                                               December 16, 2003


     "New Funds Amount" has the meaning set forth in Section 2.02(d).

     "Notice  of  Commitment  Increase"  has the  meaning  set forth in  Section
2.02(b).

     "Obligors"  means  the  Borrower  and the  Subsidiary  Guarantors,  each an
"Obligor".

     "Oil and Gas Properties" means Hydrocarbon Interests; the properties now or
hereafter pooled or unitized with Hydrocarbon Interests;  all presently existing
or future  unitization,  pooling agreements and declarations of pooled units and
the units created thereby  (including without limitation all units created under
orders, regulations and rules of any Governmental Authority having jurisdiction)
which may affect all or any portion of the Hydrocarbon Interests; all pipelines,
gathering  lines,  compression  facilities,  tanks and  processing  plants;  all
interests  held in  royalty  trusts  whether  presently  existing  or  hereafter
created;  all  Hydrocarbons  in and  under and  which  may be  produced,  saved,
processed  or  attributable  to the  Hydrocarbon  Interests,  the lands  covered
thereby and all Hydrocarbons in pipelines, gathering lines, tanks and processing
plants and all rents, issues, profits,  proceeds,  products,  revenues and other
incomes  from or  attributable  to the  Hydrocarbon  Interests;  all  tenements,
hereditaments,  appurtenances and properties in any way appertaining, belonging,
affixed or  incidental to the  Hydrocarbon  Interests,  and all rights,  titles,
interests and estates described or referred to above, including any and all real
property,  now owned or hereafter  acquired,  used or held for use in connection
with the operating,  working or development of any of such Hydrocarbon Interests
or property and including any and all surface leases,  rights-of-way,  easements
and  servitudes  together  with  all  additions,  substitutions,   replacements,
accessions and  attachments  to any and all of the  foregoing;  all oil, gas and
mineral leasehold and fee interests,  all overriding royalty interests,  mineral
interests,  royalty interests, net profits interests, net revenue interests, oil
payments, production payments, carried interests and any and all other interests
in Hydrocarbons;  in each case whether now owned or hereafter  acquired directly
or indirectly.

     "Other  Taxes"  means any and all  present or future  stamp or  documentary
taxes or any other excise or property  taxes,  charges or similar levies arising
from any payment made hereunder or from the  execution,  delivery or enforcement
of, or otherwise with respect to, this Agreement.

     "Participant" has the meaning set forth in Section 9.04.

     "PBGC"  means the  Pension  Benefit  Guaranty  Corporation  referred to and
defined in ERISA and any successor entity performing similar functions.

     "Permitted Encumbrances" means:

          (a) Liens imposed by law for taxes, assessments, or other governmental
     charges or  levies that are  not yet  delinquent or  are being contested in
     compliance with Section 5.04;

          (b) carriers', warehousemen's, mechanics', materialmen's, repairmen's,
     landlords, vendors, workmen, operators, and other like Liens arising in the
     ordinary course of  business or incident to  the exploration,  development,
     operation,  and  maintenance of  Hydrocarbons and  related  facilities  and
     assets and securing obligations that are  not overdue by more than  30 days
     or are being contested in compliance with Section 5.04;

                                       12




                                                               December 16, 2003


          (c) pledges and deposits  made in the  ordinary course of  business in
     compliance with  workers' compensation,  unemployment insurance,  and other
     social security laws or regulations;

          (d) deposits  to  secure  the  performance  of  bids,  tenders,  trade
     contracts,   leases,   statutory  obligations,  surety  and  appeal  bonds,
     performance bonds,  and other obligations of a like nature, in each case in
     the ordinary course of business;

          (e) judgment liens in respect  of judgments  that do not constitute an
     Event of Default under clause (k) of Article VII;

          (f) easements,   zoning   restrictions,   rights-of-way,   servitudes,
     permits, conditions, exceptions,  reservations, and similar encumbrances on
     real property imposed by law or arising  in the ordinary course of business
     that do not secure  any Indebtedness and  do not  materially interfere with
     the  ordinary  conduct  of  business  of the  Borrower  or  any  Restricted
     Subsidiary;

          (g) legal  or  equitable  encumbrances  deemed to  exist  by reason of
     negative pledges such as in Section 6.02 of this Agreement or the existence
     of any  litigation or other  legal proceeding  and any related  lis pendens
     filing  (excluding any  attachment  prior to  judgment,  judgment  lien  or
     attachment lien in aid of execution on a judgment);

          (h) rights of a  common owner  of any  interest in  property  held  by
     Borrower or any Restricted Subsidiary as a common owner;

          (i) farmout,  carried working  interest, joint operating, unitization,
     royalty, overriding royalty, sales, and similar  agreements relating to the
     exploration or development of,  or production from,  oil and gas properties
     incurred in the ordinary course of business,

          (j) Liens  arising  pursuant  to  Section  9.343 of the  Texas Uniform
     Commercial Code or  other similar statutory provisions of other states with
     respect to production purchased from others;

          (k) any  defects,   irregularities,   or  deficiencies   in  title  to
     easements, rights-of-way, or other properties which do not in the aggregate
     have a Material Adverse Effect;

          (l) Liens  on  the  stock  or  other  ownership  interest of or in any
     Unrestricted Subsidiary, provided that there is no recourse to the Borrower
     or any  Restricted  Subsidiary  other than recourse to  such stock or other
     ownership interest and proceeds thereof;

                                       13




                                                               December 16, 2003


          (m) Liens  in  renewal or  extension of any of the foregoing permitted
     Liens,  so long as  limited to the  property or  assets encumbered  and the
     amounts  of  indebtedness  secured  immediately  prior to  such  renewal or
     extension is not increased; and

          (n) Liens approved in writing by or on behalf of the Required Lenders.

     "Person" means any natural person, corporation,  limited liability company,
trust, joint venture, association, company, partnership,  Governmental Authority
or other entity.

     "Plan" means any employee  pension benefit plan (other than a Multiemployer
Plan) subject to the  provisions of Title IV of ERISA or Section 412 of the Code
or  Section  302 of ERISA,  and in respect  of which the  Borrower  or any ERISA
Affiliate  is (or, if such plan were  terminated,  would under  Section  4069 of
ERISA be deemed to be) an "employer" as defined in Section 3(5) of ERISA.

     "Prime Rate" means the rate of interest per annum  publicly  announced from
time to time by JPMorgan Chase Bank as its prime rate in effect at its principal
office in New York City;  each change in the Prime Rate shall be effective  from
and including the date such change is publicly announced as being effective.

     "Proved Reserves" means the estimated  quantities of crude oil, condensate,
natural gas and natural gas liquids that  adequate  geological  and  engineering
data  demonstrate  with  reasonable  certainty to be recoverable in future years
from proved reservoirs under existing  economic and operating  conditions (i.e.,
prices and costs as of the date the estimate is made).

     "PV" means as of any December 31, the  calculation of the net present value
of projected  future cash flows from Proved  Reserves  (using an 8.75%  discount
rate and the Administrative  Agent's customary price deck as of such date) based
upon the most recently delivered Reserve Report. For purposes of calculating the
PV, a maximum of 35% of the PV value will be included from Proved  Reserves that
are not  proved  developed  producing  reserves.  PV as of any date  other  than
December 31 shall mean the PV as of the most recent December 31.

     "Reducing Percentage Lender" has the meaning set forth in Section 2.02(d).

     "Reduction Amount" has the meaning set forth in Section 2.02(d).

     "Register" has the meaning set forth in Section 9.04.

     "Related  Parties"  means,  with  respect  to any  specified  Person,  such
Person's Affiliates and the respective directors,  officers,  employees,  agents
and advisors of such Person and such Person's Affiliates.

     "Required  Lenders" means, at any time, Lenders having Credit Exposures and
unused Commitments  representing greater than 50% of the sum of the total Credit
Exposures and unused Commitments at such time.

                                       14




                                                               December 16, 2003


     "Reserve  Report" means a report prepared as of December 31 of each year by
the Borrower with respect to the Oil and Gas  Properties of the Borrower and the
Restricted  Subsidiaries and audited at least as to 60% of the net present value
of all such Proved Reserves by Gaffney, Cline & Associates, Ryder Scott Company,
Netherland,  Sewell & Associates,  Inc. or another independent  engineering firm
selected by the Borrower and reasonably  acceptable to the Administrative Agent,
provided that as to such Proved Reserves included in the Hugoton,  Spraberry and
West Panhandle fields, such audit need only be provided every other year. In any
year that the  Proved  Reserves  included  in the  Hugoton,  Spraberry  and West
Panhandle fields are not audited,  the audit  commissioned by the Borrower shall
be as to 60% of the net  present  value of all Proved  Reserves  other than such
excluded fields.

     "Restricted  Subsidiaries"  means all Subsidiary  Guarantors  and,  without
duplication,  all  Subsidiaries  of  the  Borrower  that  are  not  Unrestricted
Subsidiaries.

     "Revolving Loan" means a Loan made pursuant to Section 2.03.

     "S&P" means Standard & Poor's.

     "Statutory  Reserve Rate" means a fraction  (expressed  as a decimal),  the
numerator of which is the number one and the  denominator of which is the number
one minus the  aggregate  of the  maximum  reserve  percentages  (including  any
marginal,  special,  emergency or supplemental  reserves) expressed as a decimal
established  by the  Board to which the  Administrative  Agent is  subject  with
respect to the Adjusted LIBO Rate, for eurocurrency  funding (currently referred
to as  "Eurocurrency  Liabilities"  in Regulation D of the Board).  Such reserve
percentages   shall  include  those  imposed  pursuant  to  such  Regulation  D.
Eurodollar  Loans shall be deemed to constitute  eurocurrency  funding and to be
subject to such reserve requirements without benefit of or credit for proration,
exemptions  or  offsets  that may be  available  from time to time to any Lender
under such Regulation D or any comparable regulation. The Statutory Reserve Rate
shall be adjusted automatically on and as of the effective date of any change in
any reserve percentage.

     "subsidiary"  means, with respect to any Person (the "parent") at any date,
any corporation,  limited liability company,  partnership,  association or other
entity the accounts of which would be  consolidated  with those of the parent in
the parent's consolidated financial statements if such financial statements were
prepared  in  accordance  with  GAAP as of  such  date,  as  well  as any  other
corporation, limited liability company, partnership, association or other entity
of which securities or other ownership  interests  representing more than 50% of
the ordinary voting power or, in the case of a partnership, more than 50% of the
general partnership interests are, as of such date, owned, controlled or held by
the parent and one or more subsidiaries of the parent.

     "Subsidiary" means any subsidiary of the Borrower.

     "Subsidiary  Guarantor"  means Pioneer Natural  Resources USA, Inc. and any
other Subsidiary that is required to execute and deliver a Subsidiary Guaranty.

     "Subsidiary Guaranty" means a Subsidiary Guaranty substantially in the form
of Exhibit D executed by a Subsidiary.

                                       15




                                                               December 16, 2003


     "Swap  Agreement"  means any agreement  with respect to any swap,  forward,
future or derivative  transaction or option or similar agreement  involving,  or
settled by reference to, one or more rates, currencies,  commodities,  equity or
debt  instruments or securities,  or economic,  financial or pricing  indices or
measures  of  economic,  financial  or  pricing  risk or  value  or any  similar
transaction or any combination of these  transactions;  provided that no phantom
stock or similar  plan  providing  for  payments  only on  account  of  services
provided by current or former directors,  officers,  employees or consultants of
the Borrower or the Subsidiaries shall be a Swap Agreement.

     "Swingline  Commitment"  means, with respect to each Swingline Lender,  the
commitment of such Swingline  Lender to make Swingline Loans. The amount of each
Swingline  Commitment  for each Swingline  Lender is  $40,000,000  and the total
Swingline Commitment is $80,000,000.

     "Swingline  Exposure" means at any time, the aggregate  principal amount of
all Swingline  Loans  outstanding  at such time.  The Swingline  Exposure of any
Lender at any time shall be its  Applicable  Percentage  of the total  Swingline
Exposure at such time.

     "Swingline  Lenders" means JPMorgan Chase Bank and Wachovia Bank,  National
Association.

     "Swingline Loan" means a Loan made pursuant to Section 2.05.

     "Taxes" means any and all present or future taxes, levies, imposts, duties,
deductions, charges or withholdings imposed by any Governmental Authority.

     "Total Cap" means, as of any date of  determination,  the sum of Total Debt
plus  Consolidated  Tangible  Net  Worth  of the  Borrower  and  the  Restricted
Subsidiaries.

     "Total  Debt"  means  as of any  date of  determination,  all  Indebtedness
(without  duplication)  of the Borrower  and the  Restricted  Subsidiaries  on a
consolidated  basis (including any Indebtedness  proposed to be incurred on such
date of determination  and excluding all Indebtedness to be paid on such date of
determination with the proceeds thereof and excluding any Indebtedness described
in clause (g) of the definition of Indebtedness herein).

     "Transactions"  means  the  execution,  delivery  and  performance  by  the
Borrower of this  Agreement,  the  borrowing  of Loans,  the use of the proceeds
thereof,  and the issuance of Letters of Credit  hereunder  and the guarantee by
the  Subsidiary  Guarantors  of the  obligations  of  the  Borrower  under  this
Agreement.

     "Type", when used in reference to any Loan or Borrowing,  refers to whether
the rate of interest on such Loan, or on the Loans comprising such Borrowing, is
determined by reference to the Adjusted LIBO Rate or the Alternate Base Rate.

     "Unrestricted Subsidiary" means:

                                       16




                                                               December 16, 2003


          (1) any Subsidiary of the  Borrower that at the time of  determination
shall be designated  an  Unrestricted  Subsidiary by a Financial  Officer of the
Borrower in the manner provided below; and

          (2) any Subsidiary of an Unrestricted Subsidiary.  A Financial Officer
may designate any  Subsidiary of the Borrower  (including  any newly acquired or
newly  formed  Subsidiary  of  the  Borrower  and a  Restricted  Subsidiary  but
excluding any Subsidiary Guarantor) to be an Unrestricted Subsidiary unless such
Subsidiary or any of its Subsidiaries  owns any Equity Interests or Indebtedness
of, or owns or holds any Lien on any  property  of,  the  Borrower  or any other
Subsidiary of the Borrower  that is not a Subsidiary of the  Subsidiary to be so
designated.  A Financial Officer may designate any Unrestricted Subsidiary to be
a  Restricted  Subsidiary;  provided,  however,  that (i) giving  effect to such
designation  shall not result in the occurrence and continuance of a Default and
(ii) any  Indebtedness of such  Subsidiary  shall not be secured by Liens at the
time of such  designation  except for Liens  permitted by Section 6.02. Any such
designation  by a Financial  Officer  shall be evidenced  to the  Administrative
Agent by promptly filing with the Administrative  Agent a copy of the resolution
of a  Financial  Officer  giving  effect to such  designation  and an  Officers'
Certificate  certifying  that  such  designation  complied  with  the  foregoing
provisions.

     "Withdrawal  Liability" means liability to a Multiemployer Plan as a result
of a complete or partial withdrawal from such Multiemployer  Plan, as such terms
are defined in Part I of Subtitle E of Title IV of ERISA.

     Section 1.02  Classification of Loans and Borrowings.  For purposes of this
Agreement,  Loans may be classified and referred to by Class (e.g., a "Revolving
Loan") or by Type (e.g.,  a  "Eurodollar  Loan") or by Class and Type  (e.g.,  a
"Eurodollar Revolving Loan").  Borrowings also may be classified and referred to
by Class  (e.g.,  a  "Revolving  Borrowing")  or by Type  (e.g.,  a  "Eurodollar
Borrowing") or by Class and Type (e.g., a "Eurodollar Revolving Borrowing").

     Section 1.03 Terms  Generally.  The definitions of terms herein shall apply
equally to the  singular  and plural  forms of the terms  defined.  Whenever the
context may require,  any pronoun  shall  include the  corresponding  masculine,
feminine and neuter forms. The words "include", "includes" and "including" shall
be deemed to be followed  by the phrase  "without  limitation".  The word "will"
shall be  construed  to have the same  meaning  and effect as the word  "shall".
Unless the context requires  otherwise (a) any definition of or reference to any
agreement,  instrument or other document  herein shall be construed as referring
to such  agreement,  instrument or other  document as from time to time amended,
supplemented  or  otherwise  modified  (subject  to  any  restrictions  on  such
amendments,  supplements or modifications  set forth herein),  (b) any reference
herein to any Person shall be construed to include such Person's  successors and
assigns, (c) the words "herein", "hereof" and "hereunder",  and words of similar
import, shall be construed to refer to this Agreement in its entirety and not to
any  particular  provision  hereof,  (d)  all  references  herein  to  Articles,
Sections,  Exhibits  and  Schedules  shall be construed to refer to Articles and
Sections of, and Exhibits and  Schedules  to, this  Agreement  and (e) the words
"asset" and  "property"  shall be  construed to have the same meaning and effect
and to refer to any and all  tangible  and  intangible  assets  and  properties,
including cash, securities, accounts and contract rights.

                                       17



                                                               December 16, 2003


     Section 1.04 Accounting Terms; GAAP. Except as otherwise expressly provided
herein,  all terms of an  accounting  or financial  nature shall be construed in
accordance  with GAAP,  as in effect from time to time;  provided  that,  if the
Borrower  notifies  the  Administrative  Agent  that the  Borrower  requests  an
amendment  to any  provision  hereof  to  eliminate  the  effect  of any  change
occurring  after  the date  hereof in GAAP  (including  but not  limited  to any
Statement of Financial  Accounting  Standards) or in the application  thereof on
the operation of such  provision (or if the  Administrative  Agent  notifies the
Borrower that the Required  Lenders request an amendment to any provision hereof
for such  purpose),  regardless  of whether any such  notice is given  before or
after such change in GAAP or in the  application  thereof,  then such  provision
shall be interpreted  on the basis of GAAP as in effect and applied  immediately
before such change shall have become effective until such notice shall have been
withdrawn or such provision amended in accordance herewith.

                                   ARTICLE II
                                   THE CREDITS

     Section 2.01  Commitments.  Subject to the terms and  conditions  set forth
herein,  each Lender agrees to make  Revolving  Loans in dollars to the Borrower
from time to time  during  the  Availability  Period in an  aggregate  principal
amount that will not result in (i) such Lender's Credit Exposure  exceeding such
Lender's  Commitment or (ii) the sum of the total Credit Exposures exceeding the
total  Commitments.  Within the  foregoing  limits and  subject to the terms and
conditions  set forth  herein,  the  Borrower  may borrow,  prepay and  reborrow
Revolving Loans.

     Section 2.02     Commitment Increase.

          (a) Subject to the terms and conditions set forth herein, the Borrower
shall have the right,  without  the  consent of the  Lenders  but with the prior
approval of the Administrative  Agent, to cause from time to time an increase in
the  Commitments  of the  Lenders (a  "Commitment  Increase")  by adding to this
Agreement one or more additional  financial  institutions  that is not already a
Lender hereunder and that is reasonably satisfactory to the Administrative Agent
(each a "CI  Lender") or by allowing  one or more  existing  Lenders to increase
their  respective  Commitments;  provided,  however that (i) no Event of Default
shall have occurred which is continuing, no such Commitment Increase shall cause
the Commitments under this Agreement to exceed $1,000,000,000, (iii) no Lender's
Commitment  shall be increased  without such Lender's prior written  consent and
(iv) if, on the  effective  date of such  increase,  any Loans have been funded,
then  the  Borrower  shall be  obligated  to pay any  breakage  fees or costs in
connection with the reallocation of such outstanding Loans.

          (b) Any Commitment Increase shall be requested by  written notice from
the Borrower to the Administrative Agent (a "Notice of Commitment  Increase") in
the  form  of  Exhibit  B  attached   hereto  and  shall  be   approved  by  the
Administrative  Agent, such consent to not be unreasonably  withheld.  Each such
Notice of Commitment  Increase shall specify (i) the proposed  effective date of
such Commitment Increase,  which date shall be no earlier than five (5) Business

                                       18



                                                               December 16, 2003


Days after  receipt by the  Administrative  Agent of such  Notice of  Commitment
Increase,  (ii) the amount of the requested  Commitment  Increase (provided that
after giving effect to such requested Commitment Increase,  the aggregate amount
of the  Commitments  does not exceed the amount set forth in subsection  (a)(ii)
above),  (iii) the  identity  of each CI Lender  or  Lender  that has  agreed in
writing  to  increase  its  Commitment  hereunder,  and (iv) the  amount  of the
respective  Commitments of the then existing Lenders and the CI Lenders from and
after  the  Commitment   Increase   Effective  Date  (as  defined  below).   The
Administrative  Agent shall review each Notice of Commitment  Increase and shall
notify the  Borrower  whether or not the  Administrative  Agent  consents to the
proposed  Commitment  Increase.  If the  Administrative  Agent  consents to such
Commitment  Increase  (such  consent  not  to  be  unreasonably  withheld),  the
Administrative  Agent shall  execute a  counterpart  of the Notice of Commitment
Increase  and such  Commitment  Increase  shall  be  effective  on the  proposed
effective  date  set  forth  in  the  Notice  of  Commitment  Increase  (if  the
Administrative  Agent  consented  to  such  Commitment  Increase  prior  to such
proposed date) or on another date agreed to by the Administrative  Agent and the
Borrower (such date referred to as the "Commitment Increase Effective Date").

          (c) On each  Commitment  Increase  Effective Date,  to the extent that
there are Loans  outstanding as of such date, (i) each CI Lender shall,  by wire
transfer of immediately  available funds,  deliver to the  Administrative  Agent
such CI Lender's New Funds Amount,  which amount, for each such CI Lender, shall
constitute  Loans  made by such  CI  Lender  to the  Borrower  pursuant  to this
Agreement on such Commitment  Increase  Effective Date, (ii) the  Administrative
Agent shall, by wire transfer of immediately  available  funds, pay to each then
Reducing  Percentage  Lender its Reduction Amount,  which amount,  for each such
Reducing  Percentage  Lender,  shall  constitute  a  prepayment  by the Borrower
pursuant to Section 2.11,  ratably in accordance  with the respective  principal
amounts thereof,  of the principal amounts of all then outstanding Loans of such
Reducing  Percentage  Lender, and (iii) the Borrower shall be responsible to pay
to each Lender any breakage fees or costs in connection with the reallocation of
any outstanding Loans.

          (d) For  purposes of this  Section 2.02 and  Exhibit B,  the following
defined  terms shall have the following  meanings:  (i) "New Funds Amount" means
the  amount  equal to the  product of a Lender's  increased  Commitment  or a CI
Lender's Commitment (as applicable) represented as a percentage of the aggregate
Commitments after giving effect to the Commitment Increase,  times the aggregate
principal amount of the outstanding  Loans immediately prior to giving effect to
the  Commitment  Increase,  if any, as of a Commitment  Increase  Effective Date
(without regard to any increase in the aggregate  principal amount of Loans as a
result of borrowings made after giving effect to the Commitment Increase on such
Commitment  Increase  Effective Date); (ii) "Reducing  Percentage  Lender" means
each then existing Lender  immediately  prior to giving effect to the Commitment
Increase  that does not increase its  respective  Commitment  as a result of the
Commitment  Increase and whose relative  percentage of the Commitments  shall be
reduced after giving effect to such Commitment  Increase;  and (iii)  "Reduction
Amount"  means the amount by which a Reducing  Percentage  Lender's  outstanding
Loans decrease as of a Commitment Increase Effective Date (without regard to the
effect of any borrowings made on such Commitment  Increase  Effective Date after
giving effect to the Commitment Increase).

                                       19




                                                               December 16, 2003


          (e) Each Commitment Increase  shall become effective on its Commitment
Increase Effective Date and upon such effectiveness (i) the Administrative Agent
shall record in the register  each then CI Lender's  information  as provided in
the  Notice  of   Commitment   Increase  and   pursuant  to  an   Administrative
Questionnaire  satisfactory to the  Administrative  Agent that shall be executed
and  delivered  by each CI Lender to the  Administrative  Agent on or before the
Commitment  Increase  Effective Date, (ii) Schedule 2.01 hereof shall be amended
and restated to set forth all Lenders  (including  any CI Lenders)  that will be
Lenders  hereunder after giving effect to such Commitment  Increase (which shall
be set forth in Annex I to the applicable Notice of Commitment Increase) and the
Administrative  Agent shall distribute to each Lender (including each CI Lender)
a copy of such  amended and  restated  Schedule  2.01,  and (iii) each CI Lender
identified on the Notice of  Commitment  Increase for such  Commitment  Increase
shall be a "Lender" for all purposes under this Agreement.

     Section 2.03     Revolving Loans and Borrowings.

     (a) Each Revolving Loan shall be made as part of a Borrowing  consisting of
Revolving Loans made by the Lenders ratably in accordance with their  respective
Commitments.  The failure of any Lender to make any Loan  required to be made by
it shall not relieve any other  Lender of its  obligations  hereunder;  provided
that  the  Commitments  of the  Lenders  are  several  and no  Lender  shall  be
responsible for any other Lender's failure to make Loans as required.

     (b) Subject to Section 2.14,  each Revolving  Borrowing  shall be comprised
entirely  of ABR  Loans or  Eurodollar  Loans as the  Borrower  may  request  in
accordance herewith. Each Lender at its option (but subject to Section 2.19) may
make any Eurodollar  Loan by causing any domestic or foreign branch or Affiliate
of such  Lender to make such Loan;  provided  that any  exercise  of such option
shall not affect the obligation of the Borrower to repay such Loan in accordance
with the terms of this Agreement.

     (c)  At the  commencement  of  each  Interest  Period  for  any  Eurodollar
Revolving  Borrowing,  such Borrowing shall be in an aggregate amount that is an
integral  multiple of $1,000,000 and not less than $5,000,000.  At the time that
each ABR Revolving  Borrowing is made,  such Borrowing  shall be in an aggregate
amount that is an integral  multiple of $1,000,000 and not less than $5,000,000;
provided that an ABR Revolving  Borrowing may be in an aggregate  amount that is
equal to the entire unused balance of the total  Commitments or that is required
to finance the  reimbursement  of an LC  Disbursement as contemplated by Section
2.06(e).  Borrowings of more than one Type and Class may be  outstanding  at the
same time;  provided that there shall not at any time be more than a total of 10
Eurodollar Revolving Borrowings outstanding.

     (d)  Notwithstanding  any other provision of this  Agreement,  the Borrower
shall not be  entitled  to  request,  or to elect to  convert or  continue,  any
Revolving  Borrowing if the Interest Period requested with respect thereto would
end after the Maturity Date.

     Section 2.04  Requests  for  Revolving  Borrowings.  To request a Revolving
Borrowing, the Borrower shall notify the Administrative Agent of such request by
telephone (a) in the case of a Eurodollar Borrowing,  not later than 12:00 noon,
New York  City  time,  three  Business  Days  before  the  date of the  proposed
Borrowing  and (b) in the case of an ABR  Borrowing,  not later than 12:00 noon,
New York City time, on the same Business Day of the proposed Borrowing; provided
that any such notice of an ABR Borrowing to finance the  reimbursement  of an LC
Disbursement  as  contemplated  by Section  2.06(e)  may be given not later than
12:00 noon, New York City time, on the date of the proposed Borrowing. Each such
telephonic  Borrowing  Request  shall be  irrevocable  and  shall  be  confirmed
promptly by hand delivery or telecopy to the  Administrative  Agent of a written
Borrowing Request in a form approved by the  Administrative  Agent and signed by
the Borrower.  Each such telephonic and written  Borrowing Request shall specify
the following information in compliance with Section 2.02:

                                       20



                                                               December 16, 2003


          (i) the aggregate amount of the requested Borrowing;

          (ii) the date of such Borrowing, which shall be a Business Day;

          (iii) whether such Borrowing is to be an ABR Borrowing or a Eurodollar
Borrowing;

          (iv) in the  case of a  Eurodollar  Borrowing,  the  initial  Interest
Period to be applicable  thereto,  which shall be a period  contemplated  by the
definition of the term "Interest Period"; and

          (v) the  location and number  of the Borrower's account to which funds
are to be disbursed, which shall comply with the requirements of Section 2.07.

If no election as to the Type of  Revolving  Borrowing  is  specified,  then the
requested  Borrowing  shall  be an  ABR  Borrowing.  If no  Interest  Period  is
specified with respect to any requested Eurodollar Revolving Borrowing, then the
Borrower  shall be deemed to have  selected  an  Interest  Period of one month's
duration.  Promptly  following receipt of a Borrowing Request in accordance with
this Section,  the Administrative  Agent shall advise each Lender of the details
thereof  and of the  amount  of  such  Lender's  Loan  to be made as part of the
requested Borrowing.

     Section 2.05     Swingline Loans.

     (a) Subject to the terms and  conditions  set forth  herein,  the Swingline
Lenders  agree to make  Swingline  Loans in dollars to the Borrower from time to
time during the  Availability  Period ratably in accordance  with its respective
Swingline  Commitment,  in an aggregate principal amount at any time outstanding
that  will not  result in (i) the  aggregate  principal  amount  of  outstanding
Swingline  Loans  exceeding for the  Swingline  Lender  $40,000,000  or for both
Swingline Lenders  $80,000,000 or (ii) the total Credit Exposures  exceeding the
total Commitments;  provided that the Swingline Lenders shall not be required to
make a Swingline Loan to refinance an  outstanding  Swingline  Loan.  Within the
foregoing  limits and subject to the terms and conditions set forth herein,  the
Borrower may borrow,  prepay and reborrow  Swingline  Loans.  The failure of any
Swingline  Lender to make any Swingline Loan required to be made by it shall not
relieve any other Swingline Lender of its obligations  hereunder;  provided that
the Swingline  Commitments of the Swingline Lenders are several and no Swingline
Lender shall be responsible  for any other  Swingline  Lender's  failure to make
Loans as required. Each Swingline Loan shall be in an amount that is an integral
multiple of $1,000,000 and not less than $5,000,000;  provided, that a Swingline
Loan may be in an aggregate amount that is equal to the entire available balance
of  the  total  Swingline  Commitments  or  that  is  required  to  finance  the
reimbursement of an LC Disbursement as contemplated by Section 2.06(c).

                                       21



                                                               December 16, 2003


     (b)  To  request  a  Swingline   Loan,   the  Borrower   shall  notify  the
Administrative Agent of such request by telephone  (confirmed by telecopy),  not
later than 1:00 p.m.,  New York City  time,  on the day of a proposed  Swingline
Loan. Each such notice shall be irrevocable and shall specify the requested date
(which shall be a Business Day) and amount of the requested  Swingline Loan. The
Administrative  Agent will  promptly  advise each  Swingline  Lender of any such
notice received from the Borrower. Each Swingline Lender shall make its pro rata
share of each Swingline Loan available to the  Administrative  Agent who will in
turn make such amount received available to the Borrower by means of a credit to
the general deposit account of the Borrower with the  Administrative  Agent (or,
in the case of a  Swingline  Loan made to  finance  the  reimbursement  of an LC
Disbursement as provided in Section 2.06(e),  by remittance to the Issuing Bank)
by 3:00 p.m., New York City time, on the requested date of such Swingline Loan.

     (c) The Swingline Lenders may by written notice given to the Administrative
Agent not later than 10:00 a.m., New York City time, on any Business Day require
the Lenders to acquire  participations  on such Business Day in all or a portion
of the  Swingline  Loans  outstanding.  Such notice shall  specify the aggregate
amount of Swingline  Loans in which  Lenders  will  participate.  Promptly  upon
receipt of such notice,  the  Administrative  Agent will give notice  thereof to
each Lender,  specifying in such notice such Lender's  Applicable  Percentage of
such Swingline Loan or Loans. Each Lender hereby absolutely and  unconditionally
agrees,  upon receipt of notice as provided above, to pay to the  Administrative
Agent,  for the  account of each  Swingline  Lender,  such  Lender's  Applicable
Percentage of such Swingline Loan or Loans. Each Lender  acknowledges and agrees
that its  obligation to acquire  participations  in Swingline  Loans pursuant to
this Section 2.05(c) is absolute and  unconditional and shall not be affected by
any  circumstance  whatsoever,  including the  occurrence  and  continuance of a
Default or  reduction  or  termination  of the  Commitments,  and that each such
payment shall be made without any offset,  abatement,  withholding  or reduction
whatsoever.  Each Lender  shall  comply with its  obligation  under this Section
2.05(c) by wire transfer of immediately  available  funds, in the same manner as
provided in Section  2.07 with respect to Loans made by such Lender (and Section
2.07 shall apply, mutatis mutandis,  to the payment obligations of the Lenders),
and the  Administrative  Agent shall  promptly pay to the Swingline  Lenders the
amounts so  received  by it from the  Lenders.  The  Administrative  Agent shall
notify  the  Borrower  of any  participations  in any  Swingline  Loan  acquired
pursuant to this Section  2.05(c),  and  thereafter  payments in respect of such
Swingline  Loan  shall  be  made  to the  Administrative  Agent  and  not to the
Swingline Lenders.  Any amounts received by a Swingline Lender from the Borrower
(or other party on behalf of the Borrower) in respect of a Swingline  Loan after
receipt by such  Swingline  Lender of the  proceeds of a sale of  participations
therein shall be promptly remitted to the Administrative Agent; any such amounts
received  by  the  Administrative  Agent  shall  be  promptly  remitted  by  the
Administrative Agent to the Lenders that shall have made their payments pursuant
to this Section  2.05(c) and to such Swingline  Lender,  as their  interests may
appear;  provided  that any such  payment  so  remitted  shall be repaid to such
Swingline Lender or to the  Administrative  Agent, as applicable,  if and to the
extent such  payment is required to be refunded to the  Borrower for any reason.
The  purchase of  participations  in a Swingline  Loan  pursuant to this Section
2.05(c) shall not relieve the Borrower of any default in the payment thereof.

                                       22




                                                               December 16, 2003


     Section 2.06     Letters of Credit.

     (a) General. The Borrower, the Administrative Agent, Bank of America, N.A.,
as the Issuing  Bank,  and Lenders  hereby  agree that all  Existing  Letters of
Credit  shall be deemed to be issued under this  Agreement  as of the  Effective
Date and shall  constitute  Letters of Credit hereunder for all purposes (except
that the  Issuing  Bank's  standard  issuance  fee shall not be  payable on such
deemed issuance).  Except as provided in Section 2.06(i),  Bank of America, N.A.
shall only  serve as  Issuing  Bank for the  Existing  Letters  of  Credit,  and
JPMorgan  Chase  shall  serve as Issuing  Bank for all other  Letters of Credit.
Subject to the terms and conditions  set forth herein,  the Borrower may request
the issuance of standby  Letters of Credit,  in dollars and in a form reasonably
acceptable to the  Administrative  Agent and the applicable Issuing Bank, at any
time and from time to time during the Availability  Period.  In the event of any
inconsistency  between the terms and  conditions of this Agreement and the terms
and conditions of any form of letter of credit  application  or other  agreement
submitted  by the  Borrower  to,  or  entered  into by the  Borrower  with,  the
applicable  Issuing  Bank  relating  to any  Letter  of  Credit,  the  terms and
conditions of this Agreement shall control.

     (b) Notice of Issuance,  Amendment,  Renewal, Extension; Certain Condition.
To request  the  issuance  of a Letter of Credit (or the  amendment,  renewal or
extension of an outstanding  Letter of Credit),  the Borrower shall hand deliver
or telecopy (or transmit by electronic communication,  if arrangements for doing
so have been approved by the applicable  Issuing Bank) to the applicable Issuing
Bank and the  Administrative  Agent (reasonably in advance of the requested date
of issuance,  amendment,  renewal or extension) a notice requesting the issuance
of a Letter of  Credit,  or  identifying  the  Letter  of Credit to be  amended,
renewed or extended, and specifying the date of issuance,  amendment, renewal or
extension  (which  shall be a Business  Day),  the date on which such  Letter of
Credit is to expire (which shall comply with paragraph (c) below), the amount of
such Letter of Credit, the name and address of the beneficiary  thereof and such
other information as shall be necessary to prepare,  amend, renew or extend such
Letter of Credit.  If requested  by an Issuing  Bank,  the  Borrower  also shall
submit a letter of credit  application on such Issuing  Bank's  standard form in
connection  with any request for a Letter of Credit;  provided that no provision
in such  application  shall be deemed  effective  to the extent  such  provision
contains,  provides for, or requires,  representations,  warranties,  covenants,
security  interests,  Liens,  indemnities,  reimbursements of costs or expenses,
events  of  defaults,  remedies,  or  standards  of care or to the  extent  such
provision  conflicts or is inconsistent with this Agreement.  A Letter of Credit
shall be  issued,  amended,  renewed  or  extended  only if (and upon  issuance,
amendment,  renewal or extension of each Letter of Credit the Borrower  shall be
deemed to represent and warrant  that),  after giving  effect to such  issuance,
amendment,   renewal  or  extension  (i)  the  LC  Exposure   shall  not  exceed
$100,000,000  and (ii) the total  Credit  Exposures  shall not  exceed the total
Commitments.

     (c) Expiration  Date. Each Letter of Credit shall expire at or prior to the
close of  business on the earlier of (i) the date one year after the date of the
issuance of such  Letter of Credit (or, in the case of any renewal or  extension
thereof,  one year after such  renewal or  extension)  and (ii) the date that is
five Business Days prior to the Maturity Date.

                                       23




                                                               December 16, 2003


     (d)  Participation.  By the issuance of a Letter of Credit (or an amendment
to a Letter of Credit  increasing  the amount  thereof)  and without any further
action on the part of the Issuing Banks or the Lenders, the Issuing Banks hereby
grant to each Lender,  and each Lender hereby acquires from the Issuing Banks, a
participation  in such  Letter  of  Credit  equal  to such  Lender's  Applicable
Percentage  of the aggregate  amount  available to be drawn under such Letter of
Credit. In consideration and in furtherance of the foregoing, each Lender hereby
absolutely and  unconditionally  agrees to pay to the Administrative  Agent, for
the account of the Issuing Banks, such Lender's Applicable Percentage of each LC
Disbursement made by the Issuing Banks and not reimbursed by the Borrower on the
date due as provided  in  paragraph  (e) below  below,  or of any  reimbursement
payment  required  to be refunded to the  Borrower  for any reason.  Each Lender
acknowledges and agrees that its obligation to acquire  participations  pursuant
to this paragraph in respect of Letters of Credit is absolute and  unconditional
and  shall  not  be  affected  by any  circumstance  whatsoever,  including  any
amendment,  renewal or extension of any Letter of Credit or the  occurrence  and
continuance  of a Default or reduction or termination  of the  Commitments,  and
that each such payment shall be made without any offset, abatement,  withholding
or reduction whatsoever.

     (e)  Reimbursement.  If an Issuing Bank shall make any LC  Disbursement  in
respect of a Letter of Credit, the Borrower shall reimburse such LC Disbursement
by paying to the  Administrative  Agent an amount equal to such LC  Disbursement
not  later  than  1:00  p.m.,  New York  City  time,  on the date  that  such LC
Disbursement  is made,  if the Borrower  shall have  received  notice of such LC
Disbursement  prior to 10:00 a.m., New York City time, on such date, or, if such
notice has not been  received by the  Borrower  prior to such time on such date,
then not later than 12:00 noon, New York City time, on (i) the Business Day that
the Borrower  receives  such notice,  if such notice is received  prior to 10:00
a.m.,  New York City  time,  on the day of  receipt,  or (ii) the  Business  Day
immediately  following the day that the Borrower  receives such notice,  if such
notice is not received prior to such time on the day of receipt;  provided that,
if such LC Disbursement is not less than  $5,000,000,  the Borrower may, subject
to the  conditions  to borrowing set forth  herein,  request in accordance  with
Section 2.04 that such payment be financed  with an ABR  Revolving  Borrowing or
Swingline  Loan in an  equivalent  amount  and, to the extent so  financed,  the
Borrower's  obligation to make such payment shall be discharged  and replaced by
the resulting ABR Revolving  Borrowing or Swingline  Loan. If the Borrower fails
to make such payment when due, the Administrative Agent shall notify each Lender
of the  applicable  LC  Disbursement,  the payment then due from the Borrower in
respect  thereof  and such  Lender's  Applicable  Percentage  thereof.  Promptly
following  receipt of such notice,  each Lender shall pay to the  Administrative
Agent its  Applicable  Percentage of the payment then due from the Borrower,  in
the same manner as provided in Section  2.07 with  respect to Loans made by such
Lender  (and  Section  2.07  shall  apply,  mutatis  mutandis,  to  the  payment
obligations of the Lenders),  and the Administrative Agent shall promptly pay to
the  Issuing  Bank the  amounts so  received  by it from the  Lenders.  Promptly
following receipt by the  Administrative  Agent of any payment from the Borrower
pursuant to this  paragraph,  the  Administrative  Agent shall  distribute  such
payment to the Issuing Bank or, to the extent that  Lenders  have made  payments
pursuant to this  paragraph to reimburse the Issuing Bank,  then to such Lenders
and the Issuing Bank as its interests  may appear.  Any payment made by a Lender
pursuant to this paragraph to reimburse the Issuing Bank for any LC Disbursement
(other than the funding of ABR Revolving Loans or Swingline Loan as contemplated
above)  shall not  constitute  a Loan and shall not relieve the  Borrower of its
obligation to reimburse such LC Disbursement.

                                       24




                                                               December 16, 2003


     (f)  Obligations  Absolute.  The  Borrower's  obligation  to  reimburse  LC
Disbursements   as  provided  in   paragraph   (e)  above  shall  be   absolute,
unconditional  and  irrevocable,  and shall be performed  strictly in accordance
with the terms of this Agreement under any and all circumstances  whatsoever and
irrespective  of (i) any lack of  validity  or  enforceability  of any Letter of
Credit or this Agreement,  or any term or provision  therein,  (ii) any draft or
other  document  presented  under a  Letter  of  Credit  proving  to be  forged,
fraudulent  or invalid in any respect or any  statement  therein being untrue or
inaccurate in any respect,  or (iii) any other event or circumstance  whatsoever
(other than failure to comply with the terms of such Letter of Credit),  whether
or not similar to any of the  foregoing,  that might,  but for the provisions of
this Section,  constitute a legal or equitable  discharge of, or provide a right
of  setoff  against,   the  Borrower's   obligations   hereunder.   Neither  the
Administrative  Agent,  the  Lenders  nor the  Issuing  Banks,  nor any of their
Related Parties,  shall have any liability or  responsibility by reason of or in
connection  with the issuance or transfer of any Letter of Credit or any payment
or  failure  to  make  any  payment  thereunder  (irrespective  of  any  of  the
circumstances  referred to in the preceding sentence),  or any error,  omission,
interruption,  loss or delay in transmission or delivery of any draft, notice or
other  communication  under or relating to any Letter of Credit  (including  any
document required to make a drawing thereunder),  any error in interpretation of
technical terms or any consequence arising from causes beyond the control of the
Issuing Banks;  provided that the foregoing shall not be construed to excuse the
Issuing Banks from liability to the Borrower to the extent of any direct damages
(as  opposed  to  consequential  damages,  claims in respect of which are hereby
waived by the Borrower to the extent  permitted by  applicable  law) suffered by
the Borrower that are caused by the Issuing Banks' failure to exercise care when
determining  whether  drafts  and other  documents  presented  under a Letter of
Credit comply with the terms thereof.  The parties hereto  expressly agree that,
in the  absence of gross  negligence  or willful  misconduct  on the part of the
Issuing Banks (as finally determined by a court of competent jurisdiction),  the
Issuing Banks shall be deemed to have exercised care in each such determination.
In furtherance of the foregoing and without limiting the generality thereof, the
parties agree that,  with respect to documents  presented  which appear on their
face to be in substantial  compliance with the terms of a Letter of Credit,  the
Issuing Banks may, in their sole discretion, either accept and make payment upon
such documents without responsibility for further  investigation,  regardless of
any notice or information to the contrary,  or refuse to accept and make payment
upon such  documents if such  documents  are not in strict  compliance  with the
terms of such Letter of Credit.

     (g) Disbursement  Procedures.  The Issuing Banks shall,  promptly following
receipt  thereof,  examine all  documents  purporting  to represent a demand for
payment under a Letter of Credit.  The Issuing Banks shall  promptly  notify the
Administrative  Agent and the Borrower by telephone  (confirmed  by telecopy) of
such demand for payment and whether the Issuing  Banks have made or will make an
LC Disbursement thereunder; provided that any failure to give or delay in giving
such notice shall not relieve the Borrower of its  obligation  to reimburse  the
Issuing Banks and the Lenders with respect to any such LC Disbursement.

     (h) Interim  Interest.  If an Issuing Bank shall make any LC  Disbursement,
then,  unless the Borrower shall  reimburse such LC  Disbursement in full on the
date  such LC  Disbursement  is made,  the  unpaid  amount  thereof  shall  bear
interest,  for each day from and including the date such LC Disbursement is made
to but excluding the date that the Borrower reimburses such LC Disbursement,  at
the rate per annum then applicable to ABR Revolving Loans; provided that, if the

                                       25




                                                               December 16, 2003


Borrower fails to reimburse such LC Disbursement  when due pursuant to paragraph
(e) above,  then Section 2.13(d) shall apply.  Interest accrued pursuant to this
paragraph  shall be for the account of the Issuing  Bank,  except that  interest
accrued on and after the date of payment by any Lender pursuant to paragraph (e)
of this Section to  reimburse  the Issuing Bank shall be for the account of such
Lender to the extent of such payment.

     (i)  Replacement of the Issuing  Banks.  An Issuing Bank may be replaced at
any time by written agreement among the Borrower,  the Administrative Agent, the
replaced Issuing Bank and the successor Issuing Bank. The  Administrative  Agent
shall notify the Lenders of any such replacement of an Issuing Bank. At the time
any such replacement shall become  effective,  the Borrower shall pay all unpaid
fees  accrued for the account of the replaced  Issuing Bank  pursuant to Section
2.12(b).  From and after the  effective  date of any such  replacement,  (i) the
successor  Issuing Bank shall have all the rights and obligations of the Issuing
Bank  under  this  Agreement  with  respect  to  Letters  of Credit to be issued
thereafter and (ii) references herein to the term "Issuing Bank" shall be deemed
to refer to such successor or to any previous Issuing Bank, or to such successor
and all  previous  Issuing  Banks,  as the  context  shall  require.  After  the
replacement of an Issuing Bank hereunder, the replaced Issuing Bank shall remain
a party hereto and shall  continue to have all the rights and  obligations of an
Issuing Bank under this Agreement with respect to Letters of Credit issued by it
prior to such replacement, but shall not be required to issue additional Letters
of Credit.

     (j) Cash  Collateralization.  If the Loans have become  immediately due and
payable  pursuant to Article VII, on the Business Day following the Business Day
that  the  Borrower  receives  notice  from  the  Administrative  Agent  (at the
direction of Required  Lenders) or the Required Lenders demanding the deposit of
cash  collateral  pursuant to this  paragraph,  the Borrower shall deposit in an
account with the Administrative  Agent, in the name of the Administrative  Agent
and for the benefit of the  Lenders,  an amount in cash equal to the LC Exposure
as of such  date  plus any  accrued  and  unpaid  interest  on LC  Disbursements
comprising  such LC Exposure.  Such deposit shall be held by the  Administrative
Agent as collateral for the payment and  performance  of the  obligations of the
Borrower under this  Agreement.  The  Administrative  Agent shall have exclusive
dominion and control,  including the exclusive  right of  withdrawal,  over such
account (which shall be invested in obligations of,  obligations  guaranteed by,
or  obligations  backed by the full faith and  credit  of, the United  States of
America,  certificates of deposit of  Administrative  Agent or commercial  paper
having the highest  rating from S&P or  Moody's,  in each case  maturing in less
than 180  days).  Other  than any  interest  earned  on the  investment  of such
deposits,  which  investments shall be made at the option and sole discretion of
the Administrative  Agent and at the Borrower's risk and expense,  such deposits
shall not bear interest.  Interest or profits, if any, on such investments shall
accumulate  in such  account.  Moneys in such  account  shall be  applied by the
Administrative Agent to reimburse an Issuing Bank for LC Disbursements for which
it has not been reimbursed and, to the extent not so applied,  shall be held for
the  satisfaction  of the  reimbursement  obligations of the Borrower for the LC
Exposure at such time or, if the maturity of the Loans has been accelerated (but
subject to the consent of Lenders with LC Exposure representing greater than 50%
of the total LC  Exposure),  be  applied  to satisfy  other  obligations  of the
Borrower under this Agreement.

                                       26




                                                               December 16, 2003


     Section 2.07     Funding of Borrowings.

     (a) Each  Lender  shall  make each Loan to be made by it  hereunder  on the
proposed date thereof by wire transfer of  immediately  available  funds by 1:00
pm, New York City time, to the account of the Administrative Agent most recently
designated  by it for such  purpose  by notice  to the  Lenders;  provided  that
Swingline  Loans shall be made as provided in Section 2.05.  The  Administrative
Agent will make such Loans  available to the Borrower by promptly  crediting the
amounts so received,  in like funds,  to an account of the  Borrower  maintained
with the Administrative Agent in New York City and designated by the Borrower in
the  applicable  Borrowing  Request;  provided that ABR Revolving  Loans made to
finance the  reimbursement  of an LC Disbursement as provided in Section 2.06(e)
shall be remitted by the Administrative Agent to the applicable Issuing Bank.

     (b) Unless the  Administrative  Agent  shall have  received  notice  from a
Lender prior to the  proposed  date of any  Borrowing  that such Lender will not
make  available  to  the  Administrative  Agent  such  Lender's  share  of  such
Borrowing,  the  Administrative  Agent may assume that such Lender has made such
share  available on such date in accordance  with  paragraph (a) of this Section
and may, in reliance  upon such  assumption,  make  available  to the Borrower a
corresponding  amount. In such event, if a Lender has not in fact made its share
of the applicable  Borrowing  available to the  Administrative  Agent,  then the
applicable Lender and the Borrower  severally agree to pay to the Administrative
Agent forthwith on demand such corresponding  amount with interest thereon,  for
each day from and  including  the date  such  amount  is made  available  to the
Borrower to but excluding the date of payment to the  Administrative  Agent,  at
(i) in the case of such Lender,  the greater of the Federal Funds Effective Rate
and a rate  determined by the  Administrative  Agent in accordance  with banking
industry  rules on interbank  compensation  or (ii) in the case of the Borrower,
the interest rate  applicable to the applicable  Borrowing.  If such Lender pays
such amount to the Administrative  Agent, then such amount shall constitute such
Lender's Loan included in such Borrowing.

     Section 2.08     Interest Elections.

     (a) Each Revolving  Borrowing  initially  shall be of the Type specified in
the  applicable  Borrowing  Request and, in the case of a  Eurodollar  Revolving
Borrowing,  shall have an initial Interest Period as specified in such Borrowing
Request.  Thereafter,  the  Borrower  may elect to convert  such  Borrowing to a
different  Type or to continue such  Borrowing  and, in the case of a Eurodollar
Revolving  Borrowing,  may elect Interest Periods  therefor,  all as provided in
this Section. The Borrower may elect different options with respect to different
portions of the affected  Borrowing,  in which case each such  portion  shall be
allocated ratably among the Lenders holding the Loans comprising such Borrowing,
and the Loans  comprising  each such  portion  shall be  considered  a  separate
Borrowing.

     (b) To make an election pursuant to this Section, the Borrower shall notify
the  Administrative  Agent of such  election  by  telephone  by the time  that a
Borrowing  Request  would be required  under  Section 2.04 if the Borrower  were
requesting a Revolving  Borrowing of the Type resulting from such election to be
made on the  effective  date of such  election.  Each such  telephonic  Interest
Election  Request shall be irrevocable  and shall be confirmed  promptly by hand
delivery or telecopy to the Administrative  Agent of a written Interest Election
Request  in a form  approved  by the  Administrative  Agent  and  signed  by the
Borrower.

                                       27




                                                               December 16, 2003


     (c) Each telephonic and written Interest Election Request shall specify the
following information in compliance with Section 2.02:

          (i) the Borrowing to which such Interest Election Request applies and,
if  different  options are being  elected  with  respect to  different  portions
thereof,  the portions  thereof to be allocated to each resulting  Borrowing (in
which case the  information  to be specified  pursuant to clauses (iii) and (iv)
below shall be specified for each resulting Borrowing);

          (ii) the effective date of the election made pursuant to such Interest
Election Request, which shall be a Business Day;

          (iii) whether the resulting  Borrowing is to be an  ABR Borrowing or a
Eurodollar Borrowing; and

          (iv) if  the  resulting  Borrowing  is  a  Eurodollar  Borrowing,  the
Interest  Period to be applicable  thereto after giving effect to such election,
which shall be a period  contemplated  by the  definition of the term  "Interest
Period".

If any such Interest  Election Request requests a Eurodollar  Borrowing but does
not  specify  an  Interest  Period,  then the  Borrower  shall be deemed to have
selected an Interest Period of one month's duration.

     (d)  Promptly  following  receipt  of an  Interest  Election  Request,  the
Administrative Agent shall advise each Lender of the details thereof and of such
Lender's portion of each resulting Borrowing.

     (e) If the Borrower  fails to deliver a timely  Interest  Election  Request
with respect to a Eurodollar  Borrowing  prior to the end of the Interest Period
applicable thereto, then, unless such Borrowing is repaid as provided herein, at
the end of such  Interest  Period such  Borrowing  shall be  converted to an ABR
Borrowing. Notwithstanding any contrary provision hereof, if an Event of Default
has occurred and is continuing and the  Administrative  Agent, at the request of
the Required  Lenders,  so notifies the  Borrower,  then, so long as an Event of
Default is continuing (i) no outstanding Revolving Borrowing may be converted to
or continued as a Eurodollar  Borrowing and (ii) unless repaid,  each Eurodollar
Revolving  Borrowing  shall be converted  to an ABR  Borrowing at the end of the
Interest Period applicable thereto.

     Section 2.09     Termination and Reduction of Commitments.

     (a) Unless  previously  terminated,  the Commitments shall terminate on the
Maturity Date.

     (b) The Borrower may at any time  terminate,  or from time to time,  reduce
the Commitments; provided that (i) each reduction of the Commitments shall be in
an  amount  that  is an  integral  multiple  of  $1,000,000  and not  less  than
$5,000,000 and (ii) the Borrower  shall not terminate or reduce the  Commitments
if, after giving effect to any concurrent  prepayment of the Loans in accordance
with Section 2.11, the Credit Exposure would exceed the Commitments.

                                       28




                                                               December 16, 2003


     (c) The Borrower shall notify the  Administrative  Agent of any election to
terminate or reduce the Commitments under paragraph (b) of this Section at least
three  Business  Days  prior  to the  effective  date  of  such  termination  or
reduction,  specifying  such election and the effective  date thereof.  Promptly
following  receipt of any notice,  the  Administrative  Agent  shall  advise the
Lenders of the contents thereof.  Each notice delivered by the Borrower pursuant
to this Section shall be  irrevocable;  provided that a notice of termination of
the  Commitments  delivered  by the  Borrower  may  state  that  such  notice is
conditioned  upon the  effectiveness of other credit  facilities,  in which case
such  notice  may be revoked by the  Borrower  (by notice to the  Administrative
Agent on or prior to the  specified  effective  date) if such  condition  is not
satisfied.  Any termination or reduction of the Commitments  shall be permanent.
Each  reduction of the  Commitments  shall be made ratably  among the Lenders in
accordance with their respective Applicable Percentage.

Section 2.10     Repayment of Loans; Evidence of Debt.

     (a)  The  Borrower  hereby  unconditionally  promises  to  pay,  (i) to the
Administrative  Agent for the account of each  Lender the then unpaid  principal
amount of each  Revolving  Loan on the  Maturity  Date and (ii) with  respect to
Swingline Loans made to it, to the Administrative  Agent for the account of each
Swingline  Lender the then unpaid principal amount of each Swingline Loan on the
earlier of the Maturity Date and the Swingline  Due Date.  "Swingline  Due Date"
means for each Swingline Loan, the next Business Day from the date the Swingline
Loan has been  disbursed.  On each date that a Revolving  Borrowing is made, the
Borrower shall repay the amount of any outstanding  Swingline Loans that exceeds
$20,000,000.

     (b) Each Lender shall  maintain in  accordance  with its usual  practice an
account or accounts  evidencing the  indebtedness of the Borrower to such Lender
resulting from each Loan made by such Lender, including the amounts of principal
and interest payable and paid to such Lender from time to time hereunder.

     (c) The  Administrative  Agent  shall  maintain  accounts in which it shall
record (i) the amount of each Loan made  hereunder,  the Class and Type  thereof
and the Interest Period applicable thereto,  (ii) the amount of any principal or
interest  due and payable or to become due and payable from the Borrower to each
Lender hereunder and (iii) the amount of any sum received by the  Administrative
Agent hereunder for the account of the Lenders and each Lender's share thereof.

     (d) The entries made in the accounts  maintained  pursuant to paragraph (b)
or (c) of this  Section  shall be prima  facie  evidence  of the  existence  and
amounts of the obligations  recorded  therein;  provided that the failure of any
Lender  or the  Administrative  Agent to  maintain  such  accounts  or any error
therein shall not in any manner  affect the  obligation of the Borrower to repay
the Loans in accordance with the terms of this Agreement.

     (e)  Any  Lender  may  request  that  Loans  made by it be  evidenced  by a
promissory note. In such event, the Borrower shall prepare,  execute and deliver
to such  Lender a  promissory  note  payable to the order of such Lender (or, if
requested  by such  Lender,  to such  Lender  and its  registered  assigns)  and
substantially  in the form attached hereto as Exhibit E.  Thereafter,  the Loans
evidenced  by such  promissory  note and  interest  thereon  shall at all  times
(including after  assignment  pursuant to Section 9.04) be represented by one or
more  promissory  notes in such form  payable  to the  order of the payee  named
therein (or, if such promissory note is a registered note, to such payee and its
registered assigns).

                                       29




                                                               December 16, 2003


     Section 2.11     Prepayment of Loans.

     (a) Subject to any breakage funding costs payable pursuant to Section 2.16,
the  Borrower  shall  have the right at any time and from time to time to prepay
any Borrowing in whole or in part without premium or penalty, provided that each
prepayment is in an amount that is an integral  multiple of  $1,000,000  and not
less than $5,000,000, or if such amount is lesser, the outstanding amount of the
Borrowing,  and made subject to prior notice in accordance with paragraph (b) of
this Section.

     (b) The  Borrower  shall  notify  the  Administrative  Agent  by  telephone
(confirmed  by  telecopy)  of  any  prepayment  hereunder  (i) in  the  case  of
prepayment of a Eurodollar Revolving  Borrowing,  not later than 12:00 noon, New
York City time,  three Business Days before the date of prepayment,  (ii) in the
case of prepayment of an ABR Revolving Borrowing, not later than 12:00 noon, New
York City time, on the date of prepayment, or (iii) in the case of prepayment of
a Swingline  Loan,  not later than 12:00 noon New York City time, on the date of
prepayment.  Each  such  notice  shall be  irrevocable  and  shall  specify  the
prepayment date and the principal amount of each Borrowing or portion thereof to
be prepaid; provided that, if a notice of prepayment is given in connection with
a conditional  notice of  termination  of the  Commitments  as  contemplated  by
Section 2.09,  then such notice of  prepayment  may be revoked if such notice of
termination  is revoked in  accordance  with Section  2.09.  Promptly  following
receipt of any such notice relating to a Revolving Borrowing, the Administrative
Agent shall advise the Lenders of the contents thereof.  Each partial prepayment
of any Revolving  Borrowing shall be in an amount that would be permitted in the
case of an advance of a  Revolving  Borrowing  of the same Type as  provided  in
Section 2.02. Each prepayment of a Revolving  Borrowing shall be applied ratably
to the Loans included in the prepaid Borrowing. Prepayments shall be accompanied
by accrued interest to the extent required by Section 2.13.

     Section 2.12     Fees.

     (a) The Borrower agrees to pay to the Administrative  Agent for the account
of each Lender a commitment fee, which shall accrue at the Applicable Margin for
commitment  fees on the daily  amount of the unused  Commitment  of such  Lender
without  giving effect to such Lender's  Swingline  Exposures  during the period
from and  including  the date  hereof to but  excluding  the date on which  such
Commitment  terminates.  Accrued  Commitment fees shall be payable in arrears on
the last day of March, June, September and December of each year and on the date
on which the Commitments  terminate,  commencing on the first such date to occur
after the date hereof.  All Commitment  fees shall be computed on the basis of a
year of 365 days (or 366  days in a leap  year)  and  shall be  payable  for the
actual  number of days elapsed  (including  the first day but excluding the last
day).

     (b) The  Borrower  agrees  to pay (i) to the  Administrative  Agent for the
account of each Lender a participation fee with respect to its participations in
Letters of Credit,  which  shall  accrue at the same  Applicable  Margin used to
determine the interest rate  applicable  to  Eurodollar  Revolving  Loans on the
average daily amount of such Lender's LC Exposure (excluding any portion thereof
attributable  to  unreimbursed  LC  Disbursements)  during the  period  from and

                                       30




                                                               December 16, 2003


including  the  Effective  Date to but  excluding the later of the date on which
such Lender's Commitment  terminates and the date on which such Lender ceases to
have any LC Exposure, and to the Issuing Bank a fronting fee, which shall accrue
at the rate of 0.125% per annum on the average  daily  amount of the LC Exposure
(excluding any portion thereof  attributable  to unreimbursed LC  Disbursements)
during the period from and  including  the  Effective  Date to but excluding the
later of the date of termination of the  Commitments and the date on which there
ceases to be any LC Exposure,  as well as the Issuing Bank's  standard fees with
respect to the issuance, amendment, renewal or extension of any Letter of Credit
or processing of drawings thereunder. Participation fees and fronting fees shall
be payable in arrears on the last day of March, June,  September and December of
each year and on the date on which the Commitments terminate.  All participation
fees and fronting  fees shall be computed on the basis of a year of 365 days (or
366 days in a leap  year) and shall be  payable  for the  actual  number of days
elapsed (including the first day but excluding the last day).

     (c) The Borrower  agrees to pay to the  Administrative  Agent,  for its own
account,  fees payable in the amounts and at the times separately agreed upon in
writing between the Borrower and the Administrative Agent.

     (d)  All  fees  payable  hereunder  shall  be  paid on the  dates  due,  in
immediately  available  funds,  to the  Administrative  Agent (or to the Issuing
Bank,  in the  case of fees  payable  to it) for  distribution,  in the  case of
commitment fees and participation  fees, to the Lenders.  Fees paid shall not be
refundable under any circumstances.

     Section 2.13     Interest.

     (a) The Loans  comprising  each ABR  Borrowing  shall bear  interest at the
Alternate  Base Rate plus the Applicable  Margin,  but not to exceed the Highest
Lawful Rate.

     (b) The Loans  comprising  each Eurodollar  Revolving  Borrowing shall bear
interest at the Adjusted  LIBO Rate for the  Interest  Period in effect for such
Borrowing plus the Applicable Margin, but not to exceed the Highest Lawful Rate.

     (c) When the  Borrower  requests  a  Swingline  Loan,  such Loan shall bear
interest from the date it is disbursed at a rate to be  established  as provided
on Schedule 2.13.

     (d) Notwithstanding  the foregoing,  if any principal of or interest on any
Loan or any fee or other amount  payable by the  Borrower  hereunder is not paid
when due,  whether at stated  maturity,  upon  acceleration  or otherwise,  such
overdue amount shall bear interest,  after as well as before judgment, at a rate
per annum equal to (i) in the case of overdue principal of any Loan, 2% plus the
rate otherwise  applicable to such Loan as provided in the preceding  paragraphs
of this  Section  or (ii) in the  case of any  other  amount,  2% plus  the rate
applicable to ABR Loans as provided in paragraph (a) of this Section, but not to
exceed the Highest Lawful Rate.

                                       31




                                                               December 16, 2003


     (e)  Accrued  interest  on each Loan  shall be  payable  in arrears on each
Interest  Payment Date for such Loan and, in the case of Revolving  Loans,  upon
termination of the  Commitments;  provided that (i) interest accrued pursuant to
paragraph (d) of this Section  shall be payable on demand,  (ii) in the event of
any  repayment  or  prepayment  of any Loan (other than a  prepayment  of an ABR
Revolving Loan prior to the end of the Availability Period), accrued interest on
the  principal  amount  repaid or  prepaid  shall be payable on the date of such
repayment  or  prepayment  and  (iii)  in the  event  of any  conversion  of any
Eurodollar  Revolving  Loan  prior  to the end of the  current  Interest  Period
therefor,  accrued  interest on such Loan shall be payable on the effective date
of such conversion.

     (f) All interest  hereunder shall be computed on the basis of a year of 360
days,  except that interest  computed by reference to the Alternate Base Rate at
times when the Alternate  Base Rate is based on the Prime Rate shall be computed
on the  basis of a year of 365 days  (or 366 days in a leap  year),  and in each
case shall be payable for the actual number of days elapsed (including the first
day but excluding the last day).  The applicable  Alternate Base Rate,  Adjusted
LIBO Rate or LIBO Rate shall be determined by the Administrative  Agent and such
determination shall be conclusive absent manifest error.

     Section 2.14 Alternate Rate of Interest.  If prior to the  commencement  of
any Interest Period for a Eurodollar Borrowing (including any Swingline Loan):

     (a) the  Administrative  Agent  determines  (which  determination  shall be
conclusive  absent  manifest  error) that adequate and  reasonable  means do not
exist for  ascertaining  the Adjusted LIBO Rate or the LIBO Rate, as applicable,
for such Interest Period; or

     (b) the Administrative  Agent is advised by the Required Lenders (or in the
case of a Swingline Loan, the Swingline  Lenders) that the Adjusted LIBO Rate or
the LIBO Rate, as applicable,  for such Interest  Period will not adequately and
fairly  reflect  the cost to such  Lenders  (or  Swingline  Lender) of making or
maintaining  their Loans (or its Swingline  Loan) included in such Borrowing for
such Interest Period;

then the Administrative  Agent shall give notice thereof to the Borrower and the
Lenders by  telephone  or telecopy as promptly as  practicable  thereafter  and,
until the  Administrative  Agent  notifies the Borrower and the Lenders that the
circumstances  giving  rise to such  notice no longer  exist,  (i) any  Interest
Election Request that requests the conversion of any Revolving  Borrowing to, or
continuation  of any  Revolving  Borrowing as, a Eurodollar  Borrowing  shall be
ineffective and (ii) if any Borrowing  Request  requests a Eurodollar  Revolving
Borrowing,  such  Borrowing  shall be made as an ABR  Borrowing  and  (iii)  any
request by the Borrower for a Swingline Loan shall be ineffective; provided that
if the  circumstances  giving  rise to  such  notice  affect  only  one  Type of
Borrowing, then the other Type of Borrowing shall be permitted.

     Section 2.15     Increased Costs.

     (a) If any Change in Law shall:

          (i) impose, modify or deem applicable any reserve,  special deposit or
similar  requirement  against assets of, deposits with or for the account of, or
credit extended by, any Lender (except any such reserve requirement reflected in
the Adjusted LIBO Rate) or the Issuing Banks ; or

                                       32




                                                               December 16, 2003


          (ii) impose on any Lender or the Issuing Banks or the London interbank
market any other condition  affecting this Agreement or Eurodollar Loans made by
such Lender or any Letter of Credit or  participation  therein;  (excluding,  in
each case,  Taxes,  as to which Section 2.17 shall govern) and the result of any
of the  foregoing  shall be to  increase  the cost to such  Lender  of making or
maintaining  any Eurodollar  Loan (or of maintaining  its obligation to make any
such  Loan) or to  increase  the cost to such  Lender  or the  Issuing  Banks of
participating  in, issuing or maintaining  any Letter of Credit or to reduce the
amount of any sum  received or  receivable  by such Lender or the Issuing  Banks
hereunder (whether of principal,  interest or otherwise), then the Borrower will
pay to such  Lender or the Issuing  Banks , as the case may be, such  additional
amount or amounts as will  compensate  such Lender or the Issuing Banks , as the
case may be, for such additional costs incurred or reduction suffered.

     (b) If any  Lender or an  Issuing  Bank  determines  that any Change in Law
regarding capital requirements has or would have the effect of reducing the rate
of return on such  Lender's or the Issuing  Bank's  capital or on the capital of
such Lender's or the Issuing Bank's holding company, if any, as a consequence of
this Agreement or the Loans made by, or participations in Letters of Credit held
by, such Lender, or the Letters of Credit issued by the Issuing Bank, to a level
below that which such Lender or the Issuing Bank or such Lender's or the Issuing
Bank's  holding  company  could have achieved but for such Change in Law (taking
into consideration such Lender's or the Issuing Bank's policies and the policies
of such Lender's or the Issuing Bank's  holding  company with respect to capital
adequacy),  then from time to time the  Borrower  will pay to such Lender or the
Issuing  Bank,  as the case may be,  such  additional  amount or amounts as will
compensate  such  Lender or the  Issuing  Bank or such  Lender's  or the Issuing
Bank's holding company for any such reduction suffered.

     (c) A  certificate  of a  Lender  or the  Issuing  Bank  setting  forth  in
reasonable  detail the amount or amounts  necessary to compensate such Lender or
the Issuing  Bank or its holding  company,  as the case may be, as  specified in
paragraph  (a) or (b) of this Section  shall be delivered to the  Borrower.  The
Borrower shall pay to the Administrative Agent for the account of such Lender or
the  Issuing  Bank,  as the case  may be,  the  amount  shown as due on any such
certificate within 10 days after receipt thereof.

     (d)  Failure  or delay on the part of any  Lender  or the  Issuing  Bank to
demand  compensation  pursuant to this Section shall not  constitute a waiver of
such Lender's or the Issuing Bank's right to demand such compensation;  provided
that the  Borrower  shall not be required to  compensate a Lender or the Issuing
Bank  pursuant to this Section for any increased  costs or  reductions  incurred
more than 270 days prior to the date that such  Lender or the Issuing  Bank,  as
the case may be,  notifies the Borrower of the Change in Law giving rise to such
increased  costs  or  reductions  and of such  Lender's  or the  Issuing  Bank's
intention to claim compensation  therefor;  provided further that, if the Change
in Law giving rise to such increased  costs or reductions is  retroactive,  then
the 270-day period  referred to above shall be extended to include the period of
retroactive effect thereof.

     Section 2.16 Break Funding Payments. In the event of (a) the payment of any
principal  of any  Eurodollar  Loan  other  than on the last day of an  Interest
Period applicable  thereto  (including as a result of an Event of Default),  (b)
the conversion of any Eurodollar Loan other than on the last day of the Interest
Period  applicable  thereto,  (c) the  failure to borrow,  convert,  continue or

                                       33




                                                               December 16, 2003

prepay  any  Eurodollar  Loan on the  date  specified  in any  notice  delivered
pursuant hereto  (regardless of whether such notice may be revoked under Section
2.11(b) and is revoked in accordance  therewith),  or (d) the  assignment of any
Eurodollar  Loan other than on the last day of the  Interest  Period  applicable
thereto as a result of a request by the Borrower pursuant to Section 2.19, then,
in any such event,  the Borrower shall compensate each Lender for the loss, cost
and expense  attributable to such event. In the case of a Eurodollar  Loan, such
loss,  cost or  expense  to any  Lender  shall be  deemed to  include  an amount
determined  by such  Lender  to be the  excess,  if any,  of (i) the  amount  of
interest which would have accrued on the principal  amount of such Loan had such
event not occurred, at the Adjusted LIBO Rate that would have been applicable to
such  Loan,  for the  period  from the date of such event to the last day of the
then current  Interest  Period therefor (or, in the case of a failure to borrow,
convert or continue, for the period that would have been the Interest Period for
such  Loan),  over  (ii) the  amount  of  interest  which  would  accrue on such
principal  amount for such period at the  interest  rate which such Lender would
bid were it to bid, at the commencement of such period, for dollar deposits of a
comparable  amount  and period  from other  banks in the  eurodollar  market.  A
certificate  of any Lender  setting forth any amount or amounts that such Lender
is entitled to receive  pursuant to this Section in  reasonable  detail shall be
delivered to the Borrower.  The Borrower shall pay to the  Administrative  Agent
for the account of such Lender the amount  shown as due on any such  certificate
within 10 days after receipt thereto.

     Section 2.17     Taxes.

     (a) Any and all payments by or on account of any obligation of the Borrower
hereunder  shall  be made  free  and  clear  of and  without  deduction  for any
Indemnified  Taxes  or  Other  Taxes;  provided  that if the  Borrower  shall be
required to deduct any Indemnified Taxes or Other Taxes from such payments, then
(i) the sum payable  shall be  increased  as  necessary so that after making all
required deductions  (including deductions applicable to additional sums payable
under this Section) the Administrative  Agent,  Lender, or Issuing Banks (as the
case may be) receives an amount  equal to the sum it would have  received had no
such  deductions  been made,  (ii) the Borrower  shall make such  deductions and
(iii)  the  Borrower  shall  pay  the  full  amount  deducted  to  the  relevant
Governmental Authority in accordance with applicable law.

     (b) In  addition,  the  Borrower  shall pay any Other Taxes to the relevant
Governmental Authority in accordance with applicable law.

     (c) The Borrower shall indemnify the Administrative Agent, each Lender, and
the Issuing Banks within 10 days after  written  demand  therefor,  for the full
amount of any Indemnified Taxes or Other Taxes paid by the Administrative Agent,
such  Lender,  or the Issuing  Banks , as the case may be, on or with respect to
any  payment  by or on  account  of any  obligation  of the  Borrower  hereunder
(including   Indemnified  Taxes  or  Other  Taxes  imposed  or  asserted  on  or
attributable to amounts payable under this Section) and any penalties,  interest
and reasonable  expenses arising  therefrom or with respect thereto,  whether or
not such  Indemnified  Taxes or Other Taxes were correctly or legally imposed or
asserted by the relevant Governmental  Authority. A certificate as to the amount
of such  payment or  liability  in  reasonable  detail shall be delivered to the
Borrower by a Lender or the Issuing  Banks , or by the  Administrative  Agent on
its own behalf or on behalf of a Lender or the Issuing Banks.

                                       34




                                                               December 16, 2003


     (d) As soon as practicable  after any payment of Indemnified Taxes or Other
Taxes by the Borrower to a Governmental Authority, the Borrower shall deliver to
the Administrative Agent the original or a certified copy of a receipt issued by
such  Governmental  Authority  evidencing  such  payment,  a copy of the  return
reporting such payment or other evidence of such payment reasonably satisfactory
to the Administrative Agent.

     (e) Any Foreign  Lender that is entitled to an exemption  from or reduction
of withholding  tax under the law of the  jurisdiction  in which the Borrower is
located,  or any treaty to which such  jurisdiction is a party,  with respect to
payments under this Agreement  shall deliver to the Borrower (with a copy to the
Administrative  Agent),  at the time or times prescribed by applicable law, such
properly  completed and executed  documentation  prescribed by applicable law or
reasonably  requested  by the  Borrower as will permit such  payments to be made
without withholding or at a reduced rate.

     (f) Upon the Borrower's written request,  the Administrative Agent and each
Lender shall use reasonable  efforts to make any filings necessary to obtain any
refund, deduction or credit of any Taxes or Other Taxes as to which the Borrower
has  indemnified  it or with respect to which the  Borrower has paid  additional
amounts pursuant to this Section 2.17. If the  Administrative  Agent or a Lender
receives any material refund of any Taxes or Other Taxes as to which it has been
indemnified  by the  Borrower  or with  respect to which the  Borrower  has paid
additional  amounts pursuant to this Section 2.17, it shall pay over such refund
to the  Borrower  (but  only  to the  extent  of  indemnity  payments  made,  or
additional amounts paid, by the Borrower under this Section 2.17 with respect to
the Taxes or Other Taxes  giving  rise to such  refund),  net of all  reasonable
out-of-pocket  expenses of the  Administrative  Agent or such Lender and without
interest  (other than any interest paid by the relevant  Governmental  Authority
with respect to such refund);  provided,  that the Borrower, upon the request of
the Administrative Agent or such Lender, agrees to repay the amount paid over to
the  Borrower  (plus any  penalties,  interest or other  charges  imposed by the
relevant  Governmental  Authority) to the Administrative Agent or such Lender in
the event the  Administrative  Agent or such  Lender is  required  to repay such
refund to such  Governmental  Authority.  This Section shall not be construed to
require the Administrative Agent or any Lender to make available its tax returns
(or any other information  relating to its taxes which it deems confidential) to
the  Borrower or any other Person or to attempt to take any position to obtain a
refund,  deduction,  or credit,  which  attempt would be  inconsistent  with any
reporting position otherwise taken by the Administrative Agent or such Lender on
its applicable tax returns.

     Section 2.18     Payments Generally; Pro Rata Treatment; Sharing of
                      Set-offs.

     (a)  The  Borrower  shall  make  each  payment  required  to be  made by it
hereunder  (whether  of  principal,   interest,  fees  or  reimbursement  of  LC
Disbursements,  or of amounts  payable  under  Section  2.15,  2.16 or 2.17,  or
otherwise)  prior to 12:00  noon,  New York City time,  on the date when due, in
immediately  available  funds,  without  set-off or  counterclaim.  Any  amounts
received   after  such  time  on  any  date  may,  in  the   discretion  of  the
Administrative  Agent,  be deemed to have been  received on the next  succeeding
Business Day for purposes of  calculating  interest  thereon.  All such payments

                                       35




                                                               December 16, 2003


shall be made to the Administrative Agent at its offices at 270 Park Avenue, New
York,  New York,  except  payments to be made  directly to the Issuing  Banks or
Swingline Lender as expressly  provided herein and except that payments pursuant
to Section  9.03 shall be made  directly to the Persons  entitled  thereto.  The
Administrative  Agent shall distribute any such payments  received by it for the
account of any other  Person to the  appropriate  recipient  promptly  following
receipt  thereof.  If any payment  hereunder shall be due on a day that is not a
Business  Day,  the date for payment  shall be  extended to the next  succeeding
Business  Day,  and,  in the case of any  payment  accruing  interest,  interest
thereon  shall  be  payable  for the  period  of such  extension.  All  payments
hereunder shall be made in dollars.

     (b) If at any time insufficient  funds are received by and available to the
Administrative  Agent to pay fully all  amounts of  principal,  unreimbursed  LC
Disbursements, interest and fees then due hereunder, such funds shall be applied
(i) first,  towards  payment of interest  and fees then due  hereunder,  ratably
among the parties  entitled  thereto in accordance  with the amounts of interest
and fees then due to such parties, and (ii) second, towards payment of principal
and unreimbursed LC Disbursements then due hereunder,  ratably among the parties
entitled thereto in accordance with the amounts of principal and unreimbursed LC
Disbursements then due to such parties.

     (c) If any Lender shall, by exercising any right of set-off or counterclaim
or otherwise,  obtain  payment in respect of any principal of or interest on any
of its Revolving Loans or  participations in LC Disbursements or Swingline Loans
resulting  in such  Lender  receiving  payment  of a greater  proportion  of the
aggregate amount of its Revolving Loans and  participations  in LC Disbursements
and Swingline Loans and accrued interest thereon than the proportion received by
any other  Lender,  then the Lender  receiving  such  greater  proportion  shall
purchase  (for cash at face value)  participations  in the  Revolving  Loans and
participations  in LC Disbursements  and Swingline Loans of other Lenders to the
extent necessary so that the benefit of all such payments shall be shared by the
Lenders  ratably in  accordance  with the  aggregate  amount of principal of and
accrued interest on their respective  Revolving Loans and  participations  in LC
Disbursements and Swingline Loans;  provided that (i) if any such participations
are  purchased  and all or any  portion of the payment  giving  rise  thereto is
recovered,  such  participations  shall  be  rescinded  and the  purchase  price
restored  to the  extent  of such  recovery,  without  interest,  and  (ii)  the
provisions of this paragraph shall not be construed to apply to any payment made
by the Borrower  pursuant to and in  accordance  with the express  terms of this
Agreement  or  any  payment  obtained  by a  Lender  as  consideration  for  the
assignment of or sale of a participation  in any of its Loans or  participations
in LC Disbursements  to any assignee or participant,  other than to the Borrower
or any  Subsidiary  or  Affiliate  thereof (as to which the  provisions  of this
paragraph shall apply).  The Borrower  consents to the foregoing and agrees,  to
the  extent it may  effectively  do so under  applicable  law,  that any  Lender
acquiring a participation  pursuant to the foregoing  arrangements  may exercise
against the  Borrower  rights of set-off and  counterclaim  with respect to such
participation  as fully as if such Lender were a direct creditor of the Borrower
in the amount of such participation.

     (d) Unless the  Administrative  Agent shall have  received  notice from the
Borrower  prior to the date on which any  payment  is due to the  Administrative
Agent for the  account of the Lenders or the Issuing  Banks  hereunder  that the
Borrower will not make such payment,  the  Administrative  Agent may assume that
the Borrower has made such payment on such date in accordance  herewith and may,
in  reliance  upon such  assumption,  distribute  to the  Lenders or the Issuing
Banks,  as the case may be, the amount due. In such event,  if the  Borrower has

                                       36




                                                               December 16, 2003


not in fact made such  payment,  then each of the Lenders or the Issuing Banks ,
as the case may be,  severally  agrees  to  repay  to the  Administrative  Agent
forthwith on demand the amount so  distributed  to such Lender or Issuing  Banks
with interest  thereon,  for each day from and including the date such amount is
distributed  to it to but  excluding  the date of payment to the  Administrative
Agent,  at the greater of the Federal Funds Effective Rate and a rate determined
by the  Administrative  Agent  in  accordance  with  banking  industry  rules on
interbank compensation.

     (e) If any Lender shall fail to make any payment  required to be made by it
pursuant to Section 2.06(d) or (e), 2.07(b) or 2.18(d),  then the Administrative
Agent may, in its discretion  (notwithstanding  any contrary  provision hereof),
apply  any  amounts  thereafter  received  by the  Administrative  Agent for the
account of such Lender to satisfy such Lender's  obligations under such Sections
until all such unsatisfied obligations are fully paid.

     Section 2.19     Mitigation Obligations; Replacement of Lenders..

     (a) If any Lender  requests  compensation  under  Section  2.15,  or if the
Borrower  is  required  to  pay  any  additional  amount  to any  Lender  or any
Governmental  Authority for the account of any Lender  pursuant to Section 2.17,
then such Lender shall use reasonable  efforts to designate a different  lending
office for  funding or booking its Loans  hereunder  or to assign its rights and
obligations hereunder to another of its offices, branches or affiliates,  if, in
the judgment of such Lender,  such designation or assignment (i) would eliminate
or reduce amounts payable  pursuant to Section 2.15 or 2.17, as the case may be,
in the future and (ii) would not subject such Lender to any unreimbursed cost or
expense and would not otherwise be  disadvantageous to such Lender. The Borrower
hereby agrees to pay all reasonable costs and expenses incurred by any Lender in
connection with any such designation or assignment.

     (b) If any Lender  requests  compensation  under  Section  2.15,  or if the
Borrower  is  required  to  pay  any  additional  amount  to any  Lender  or any
Governmental  Authority for the account of any Lender  pursuant to Section 2.17,
or if any Lender  defaults in its obligation to fund Loans  hereunder,  then the
Borrower may, at its sole expense and effort, upon notice to such Lender and the
Administrative  Agent,  require  such  Lender to assign  and  delegate,  without
recourse  (in  accordance  with and  subject to the  restrictions  contained  in
Section 9.04), all its interests, rights and obligations under this Agreement to
an assignee that shall assume such  obligations  (which  assignee may be another
Lender,  if a Lender  accepts such  assignment);  provided that (i) the Borrower
shall have received the prior written consent of the Administrative  Agent (and,
if a Commitment  is being  assigned,  the Issuing  Bank) which consent shall not
unreasonably  be withheld,  (ii) such Lender shall have  received  payment of an
amount equal to the outstanding  principal of its Loans and participations in LC
Disbursements and Swingline Loans,  accrued interest  thereon,  accrued fees and
all other amounts  payable to it hereunder,  from the assignee (to the extent of
such  outstanding  principal and accrued  interest and fees) or the Borrower (in
the case of all  other  amounts)  and  (iii) in the case of any such  assignment
resulting from a claim for compensation  under Section 2.15 or payments required
to be made pursuant to Section 2.17,  such assignment will result in a reduction
in such  compensation  or  payments.  A Lender shall not be required to make any
such  assignment and  delegation  if, prior thereto,  as a result of a waiver by
such Lender or otherwise,  the  circumstances  entitling the Borrower to require
such assignment and delegation cease to apply.

                                       37




                                                               December 16, 2003


                                  ARTICLE III
                         REPRESENTATIONS AND WARRANTIES

     The Borrower represents and warrants to the Lenders that:

     Section 3.01 Organization;  Powers. Each of the Borrower and its Restricted
Subsidiaries is duly organized,  validly existing and in good standing under the
laws of the  jurisdiction  of its  organization,  has all  requisite  power  and
authority  to carry on its  business  as now  conducted  and,  except  where the
failure to do so,  individually  or in the  aggregate,  could not  reasonably be
expected to result in a Material Adverse Effect, is qualified to do business in,
and is in good  standing  in, every  jurisdiction  where such  qualification  is
required.

     Section 3.02  Authorization;  Enforceability.  The  Transactions are within
each Obligor's  corporate  powers and have been duly authorized by all necessary
corporate  and,  if  required,   stockholder  action.  This  Agreement  and  all
Subsidiary  Guaranties  have been duly  executed  and  delivered by the Obligor,
which is a party thereto,  and constitute a legal,  valid and binding obligation
of such  Obligor,  enforceable  in  accordance  with  their  terms,  subject  to
applicable  bankruptcy,  insolvency,  reorganization,  moratorium  or other laws
affecting  creditors'  rights  generally  and subject to general  principles  of
equity, regardless of whether considered in a proceeding in equity or at law.

     Section 3.03 Governmental Approvals; No Conflicts.  The Transactions (a) do
not  violate  the  charter,  by-laws or other  organizational  documents  of the
Borrower or any of its Restricted  Subsidiaries or (b) except as to matters that
could not reasonably be expected to result in a Material Adverse Effect,  (i) do
not require any consent or approval  of,  registration  or filing  with,  or any
other action by, any Governmental  Authority,  except such as have been obtained
or made and are in full force and effect,  (ii) will not violate any  applicable
law or regulation  or any order of any  Governmental  Authority,  (iii) will not
violate  or  result  in a  default  under  any  indenture,  agreement  or  other
instrument  binding upon the Borrower or any of its Restricted  Subsidiaries  or
its assets, or give rise to a right thereunder to require any payment to be made
by the Borrower or any of its Restricted Subsidiaries,  and (iv) will not result
in the creation or imposition of any Lien on any asset of the Borrower or any of
its Restricted Subsidiaries.

     Section 3.04     Financial Condition; No Material Adverse Change.

     (a) The Borrower has heretofore  furnished to the Lenders its  consolidated
balance sheet and statements of income,  stockholders' equity and cash flows (i)
as of and for the fiscal year ended  December 31,  2002,  reported on by Ernst &
Young LLP, independent public accountants,  and as of and for the fiscal quarter
and the portion of the fiscal year ended  September  30, 2003,  certified by its
Financial  Officer.  Such financial  statements  present fairly, in all material
respects, the financial position and results of operations and cash flows of the
Borrower and its consolidated Subsidiaries as of such dates and for such periods
in accordance with GAAP,  subject to year-end audit  adjustments and the absence
of footnotes in the case of the statements referred to in clause (ii) above.

     (b) Since  December 31, 2002,  through and including  the  Effective  Date,
there has been no change which could  reasonably  be expected to have a Material
Adverse Effect.

                                       38




                                                               December 16, 2003


     Section  3.05   Properties.   Each  of  the  Borrower  and  its  Restricted
Subsidiaries  has good title to, or valid  leasehold  interests in, all its real
and personal property material to its business,  except for any failure,  defect
or other matter that could not, in the aggregate, reasonably be expected to have
a Material Adverse Effect.

     Section 3.06     Litigation and Environmental Matters.

     (a) There are no actions,  suits or proceedings by or before any arbitrator
or Governmental  Authority pending against or, to the knowledge of the Borrower,
threatened  against or affecting  the Borrower or any of its  Subsidiaries  that
could reasonably be expected,  individually or in the aggregate,  to result in a
Material  Adverse  Effect  (other  than the  Disclosed  Matters)  or,  as of the
Effective Date, that involve this Agreement or the Transactions.

     (b) Except for the  Disclosed  Matters and except with respect to any other
matters that, individually or in the aggregate, could not reasonably be expected
to result in a Material  Adverse  Effect,  neither the  Borrower  nor any of its
Subsidiaries (i) has failed to comply with any  Environmental  Law or to obtain,
maintain or comply with any permit, license or other approval required under any
Environmental Law, (ii) has become subject to any Environmental Liability, (iii)
has received notice of any claim with respect to any Environmental  Liability or
(iv) knows of any basis for any Environmental Liability.

     Section 3.07 Compliance with Laws . Each of the Borrower and its Restricted
Subsidiaries  is in  compliance  with all laws,  regulations  and  orders of any
Governmental Authority applicable to it or its property except where the failure
to do so, individually or in the aggregate,  could not reasonably be expected to
result in a Material Adverse Effect. No Default has occurred and is continuing.

     Section 3.08 Investment and Holding  Company  Status.  Neither the Borrower
nor any of its  Subsidiaries  is (a) an  "investment  company" as defined in, or
subject  to  regulation  under,  the  Investment  Company  Act of  1940 or (b) a
"holding  company" as defined  in, or subject to  regulation  under,  the Public
Utility Holding Company Act of 1935.

     Section 3.09 Taxes.  Each of the Borrower and its  Restricted  Subsidiaries
has timely  filed or caused to be filed all Tax returns and reports  required to
have been  filed and has paid or  caused to be paid all Taxes  required  to have
been paid by it,  except  (a) Taxes for which the  Borrower  or such  Restricted
Subsidiary,  as  applicable,  has  set  aside  on its  books  adequate  reserves
including,  Taxes  that  are  being  contested  in  good  faith  by  appropriate
proceedings  or (b) to the extent that the failure to do so could not reasonably
be expected to result in a Material Adverse Effect.

     Section 3.10 ERISA.  No ERISA Event has occurred or is reasonably  expected
to occur that,  when taken  together  with all other such ERISA Events for which
liability  is  reasonably  expected to occur,  could  reasonably  be expected to
result in a Material  Adverse Effect.  The Borrower and each ERISA Affiliate has
fulfilled its obligations  under the minimum funding  standards of ERISA and the
Code with respect to each Plan and is in  compliance  in all  material  respects

                                       39




                                                               December 16, 2003


with the presently  applicable  provisions of ERISA and the Code with respect to
each Plan.  Neither the Borrower nor any ERISA Affiliate has (a) sought a waiver
of the minimum funding  standard under Section 412 of the Code in respect of any
Plan,  (b)  failed  to  make  any   contribution  or  payment  to  any  Plan  or
Multiemployer Plan, or made any amendment to any Plan that has resulted or could
result in the  imposition  of a Lien or the posting of a bond or other  security
under ERISA or the Code, or (c) incurred any  liability  under Title IV of ERISA
other than a liability to the PBGC for premiums under Section 4007 of ERISA that
are not past due.

     Section 3.11 Disclosure.  The information  furnished by or on behalf of the
Borrower  to the  Administrative  Agent or any  Lender  in  connection  with the
negotiation   of  this   Agreement  or  delivered   hereunder  (as  modified  or
supplemented by other information so furnished),  taken as a whole,  contains no
material  misstatement of fact nor omits to state any material fact necessary to
make the statements  therein, in the light of the circumstances under which they
were made, not materially  misleading;  provided that, with respect to projected
financial  information,  the Borrower  represents only that such information was
prepared in good faith based upon  assumptions  believed to be reasonable at the
time.

                                   ARTICLE IV
                                   CONDITIONS

     Section 4.01 Effective  Date. The  obligations of the Lenders to make Loans
and of the Issuing Banks to issue Letters of Credit  hereunder  shall not become
effective until the date on which each of the following  conditions is satisfied
(or waived in accordance with Section 9.02):

     (a) The Administrative Agent (or its counsel) shall have received from each
party hereto either (i) a counterpart of this Agreement signed on behalf of such
party or (ii) written evidence  satisfactory to the Administrative  Agent (which
may include telecopy  transmission of a signed signature page of this Agreement)
that  such  party  has  signed  a  counterpart  of  this   Agreement.   (b)  The
Administrative  Agent  shall have  received  from each  Subsidiary  Guarantor  a
Subsidiary  Guaranty  in  substantially  the form  attached  hereto as Exhibit D
signed on behalf of such Subsidiary Guarantor.

     (c) The Administrative Agent shall have received favorable written opinions
(addressed to the  Administrative  Agent and the Lenders and dated the Effective
Date) of Mark  Withrow,  general  counsel  of the  Borrower,  and of  Thompson &
Knight, LLP, outside counsel for the Borrower and Subsidiary Guarantor, covering
those matters described on Exhibit C. The Borrower hereby requests such counsels
to deliver such opinions.

     (d) The  Administrative  Agent  shall  have  received  such  documents  and
certificates as the  Administrative  Agent or its counsel may reasonably request
relating to the organization,  existence and good standing of each Obligor,  the
authorization  of the  Transactions and any other legal matters relating to each
Obligor,  this  Agreement  or  the  Transactions,  all  in  form  and  substance
satisfactory to the Administrative Agent and its counsel.

     (e) The Administrative  Agent shall have received a certificate,  dated the
Effective  Date and signed by the  President,  a Vice  President  or a Financial
Officer of the Borrower,  confirming compliance with the conditions set forth in
paragraphs (a), (b) and (c) of Section 4.02.

                                       40




                                                               December 16, 2003


     (f) The Administrative  Agent, Lenders and Co-Arrangers shall have received
all fees and other  amounts due and payable on or prior to the  Effective  Date,
including, to the extent invoiced, reimbursement or payment of all out-of-pocket
expenses required to be reimbursed or paid by the Borrower hereunder.

     (g) All  commitments  under the Existing  Credit  Agreement shall have been
terminated  in full  and all  amounts  outstanding  under  the  Existing  Credit
Agreement shall have been paid in full.

     The  Administrative  Agent shall notify the Borrower and the Lenders of the
Effective Date, and such notice shall be conclusive and binding. Notwithstanding
the foregoing,  the  obligations of the Lenders to make Loans and of the Issuing
Banks to issue Letters of Credit  hereunder  shall not become  effective  unless
each of the foregoing  conditions  is satisfied  (or waived  pursuant to Section
9.02) at or prior to 3:00 p.m.,  New York City time,  on December 31, 2003 (and,
in the event such  conditions  are not so satisfied or waived,  the  Commitments
shall terminate at such time).

     Section 4.02 Each Credit  Event.  The  obligation  of each Lender to make a
Loan on the occasion of any Borrowing, and of the Issuing Banks to issue, amend,
renew or extend  any Letter of Credit,  is  subject to the  satisfaction  of the
following conditions:

     (a) The  representations  and  warranties of the Borrower set forth in this
Agreement  and  of  the  Subsidiary  Guarantors  set  forth  in  the  Subsidiary
Guaranties  shall be true and correct on and as of the date of such Borrowing or
the date of the  issuance,  amendment,  renewal or  extension  of such Letter of
Credit, as applicable.

     (b) At the time of and immediately after giving effect to such Borrowing or
the  issuance,  amendment,  renewal or  extension  of such Letter of Credit,  as
applicable, no Default shall have occurred and be continuing.

     (c) Prior to the Mid-Investment  Grade Date, there has been no change since
December  31,  2002 that has  resulted  in a Material  Adverse  Effect  which is
continuing.

     Each  Borrowing  and each  issuance,  amendment,  renewal or extension of a
Letter of Credit shall be deemed to constitute a representation  and warranty by
the Borrower on the date thereof as to the matters  specified in paragraphs (a),
(b) and, prior to the Mid-Investment Grade Date, (c) of this Section.

                                   ARTICLE V
                              AFFIRMATIVE COVENANTS

     Until the Commitments  have expired or been terminated and the principal of
and interest on each Loan and all fees payable hereunder shall have been paid in
full and all  Letters of Credit  shall have  expired  or  terminated  and all LC
Disbursements shall have been reimbursed, the Borrower covenants and agrees with
the Lenders that:

     Section 5.01 Financial Statements and Other Information.  The Borrower will
furnish to the Administrative Agent and each Lender:

     (a) within 90 days after the end of each fiscal year of the  Borrower,  its
audited  consolidated  balance  sheet  and  related  statements  of  operations,
stockholders'  equity and cash flows as of the end of and for such year, setting

                                       41




                                                               December 16, 2003


forth in each case in comparative form the figures for the previous fiscal year,
all  reported  on by  independent  public  accountants  of  recognized  national
standing  (without a "going concern" or like  qualification or exception) to the
effect  that  such  consolidated  financial  statements  present  fairly  in all
material  respects the  financial  condition  and results of  operations  of the
Borrower and its consolidated Subsidiaries on a consolidated basis in accordance
with GAAP consistently applied;

     (b) within 45 days after the end of each of the first three fiscal quarters
of each fiscal year of the Borrower,  its consolidated balance sheet and related
statements of operations,  stockholders'  equity and cash flows as of the end of
and for such fiscal  quarter and the then  elapsed  portion of the fiscal  year,
setting forth in each case in comparative form the figures for the corresponding
period or periods of (or,  in the case of the balance  sheet,  as of the end of)
the previous  fiscal year prepared on a basis  consistent with that used on Form
10Q as required by the Securities and Exchange Commission,  all certified by one
of its  Financial  Officers as  presenting  fairly in all material  respects the
financial   condition  and  results  of  operations  of  the  Borrower  and  its
consolidated  Subsidiaries  on a  consolidated  basis in  accordance  with  GAAP
consistently  applied,  subject to normal  year-end  audit  adjustments  and the
absence of footnotes;

     (c) simultaneously  with the delivery of the financial  statements referred
to in subsections  (a) or (b) of this Section 5.01, a copy of the  certification
signed by the principal executive officer and the principal financial officer of
the Borrower (each, a "Certifying Officer") as required by Rule 13A-14 under the
Securities  Exchange Act of 1934 and a copy of the internal controls  disclosure
statement  by such  Certifying  Officers as  required  by Rule 13A-15  under the
Securities  Exchange  Act of 1934 and Final  Rules  Release  No.  33-8238 of the
United  States  Securities  and  Exchange  Commission,  each as  included in the
Borrower's  Annual Report on Form 10-K or Quarterly Report on Form 10-Q, for the
applicable fiscal period;

     (d)   concurrently   with  any  delivery  of  financial   statements  under
subsections  (a) or (b) of this  Section  5.01,  a  certificate  of a  Financial
Officer of the Borrower (i) certifying as to whether a Default has occurred and,
if a Default has occurred,  specifying the details  thereof and any action taken
or proposed to be taken with respect thereto,  and (ii) setting forth reasonably
detailed  calculations  demonstrating  compliance with Section 6.04(a),  (b) and
(c);

     (e)  promptly  after  the same  become  publicly  available,  copies of all
periodic and other reports,  proxy  statements and other  materials filed by the
Borrower or any Subsidiary with the Securities and Exchange  Commission,  or any
Governmental  Authority  succeeding  to any or all  of  the  functions  of  said
Commission,  or with any national  securities  exchange,  or  distributed by the
Borrower to its shareholders generally, as the case may be;

     (f)  promptly  after  Moody's or S&P shall have  announced  a change in the
rating  established  or  deemed  to have been  established  for the Index  Debt,
written notice of such rating change; and

                                       42




                                                               December 16, 2003


     (g) prior to the  Investment  Grade Date and prior to April 30 of each year
(commencing  April 30, 2004),  the Borrower shall furnish to the  Administrative
Agent and to each Lender a Reserve  Report,  which Reserve Report shall be dated
as of the  immediately  preceding  December  31 and shall  set forth the  Proved
Reserves  attributable to all or substantially all of the Oil and Gas Properties
then  owned  by  the  Borrower  and  its  Restricted  Subsidiaries  and  the  PV
attributable thereto as contemplated in the definition of Reserve Report;

     (h)  promptly  following  any  request  therefor,  such  other  information
regarding  the  operations,  business  affairs and  financial  condition  of the
Borrower or any Subsidiary,  or compliance with the terms of this Agreement,  as
the Administrative Agent or any Lender may reasonably request.

     Section 5.02 Notices of Material  Events.  The Borrower will furnish to the
Administrative Agent and each Lender prompt written notice of the following:

     (a) the occurrence of any Default;

     (b) the filing or  commencement  of any action,  suit or  proceeding  by or
before  any  arbitrator  or  Governmental  Authority  against or  affecting  the
Borrower or any Affiliate thereof that could reasonably be expected to result in
a Material Adverse Effect if adversely determined;

     (c) the  occurrence  of any ERISA  Event that,  alone or together  with any
other ERISA Events that have occurred, could reasonably be expected to result in
liability of the Borrower and its  Subsidiaries in an aggregate amount exceeding
$25,000,000; and

     (d) any other  development that results in, or could reasonably be expected
to result in, a Material Adverse Effect.

     Each  notice  delivered  under  this  Section  shall  be  accompanied  by a
statement of a Financial  Officer of the Borrower  setting  forth the details of
the event or development  requiring such notice and any action taken or proposed
to be taken with respect thereto.

     Section 5.03  Existence;  Conduct of Business.  The Borrower will, and will
cause each of its Restricted  Subsidiaries to, do or cause to be done all things
necessary  to  preserve,  renew  and keep in full  force  and  effect  its legal
existence and the rights, licenses,  permits, privileges and franchises material
to the conduct of its business  except for any failure to maintain,  preserve or
qualify that could not reasonably be expected to have a Material Adverse Effect;
provided  that the foregoing  shall not prohibit (i) any merger,  consolidation,
liquidation or dissolution permitted under Section 6.03 or (ii) a termination of
such  existence,  good  standing,  rights  licenses,   permits,  privileges  and
franchises of any  Restricted  Subsidiary  if Borrower  determines in good faith
that  such  termination  is in the best  interest  of  Borrower  and  could  not
reasonably be expected to have a Material Adverse Effect.

     Section 5.04 Payment of Obligations. The Borrower will, and will cause each
of its Subsidiaries to, pay its obligations, including Tax liabilities, that, if
not paid,  could  reasonably be expected to result in a Material  Adverse Effect
before the same shall  become  delinquent  or in default,  except  where (a) the
validity  or amount  thereof is being  contested  in good  faith by  appropriate
proceedings,  and (b) the Borrower or such Subsidiary has set aside on its books
adequate reserves with respect thereto in accordance with GAAP.

                                       43




                                                               December 16, 2003


     Section 5.05 Maintenance of Properties;  Insurance.  The Borrower will, and
will cause each of its  Restricted  Subsidiaries  to, (a) keep and  maintain all
property  material to the  conduct of its  business  in good  working  order and
condition,  ordinary wear and tear  excepted,  except for any failure that could
reasonably be expected to result in a Material  Adverse Effect and (b) maintain,
with  financially  sound and reputable  insurance  companies,  insurance in such
amounts  and  against  such risks as are  customarily  maintained  by  companies
engaged  in the same or  similar  businesses  operating  in the same or  similar
locations.

     Section 5.06 Books and Records;  Inspection  Rights. The Borrower will, and
will cause each of its  Subsidiaries to, keep proper books of record and account
in  which  full,  true  and  correct  entries  are  made  of  all  dealings  and
transactions in relation to its business and activities.  The Borrower will, and
will cause each of its Restricted  Subsidiaries  to, permit any  representatives
designated by the  Administrative  Agent or any Lender,  upon  reasonable  prior
notice,  to visit and inspect its properties,  to examine and make extracts from
its books and records,  and to discuss its affairs,  finances and condition with
its officers and independent  accountants,  all at such reasonable  times and as
often as reasonably requested.

     Section 5.07  Compliance  with Laws. The Borrower will, and will cause each
of its Subsidiaries to, comply with all laws,  rules,  regulations and orders of
any Governmental  Authority  applicable to it or its property,  except where the
failure to do so,  individually  or in the  aggregate,  could not  reasonably be
expected to result in a Material Adverse Effect.

     Section  5.08 Use of Proceeds  and Letters of Credit.  The  proceeds of the
Loans  will be used to repay  outstanding  bank debt and for  general  corporate
purposes.  No part of the proceeds of any Loan will be used, whether directly or
indirectly,  for any purpose that entails a violation of any of the  Regulations
of the Board, including Regulations T, U and X.

     Section 5.09  Operations.  Borrower  will,  and will cause each  Restricted
Subsidiary to, maintain as its primary business the exploration,  production and
development of oil,  natural gas and other liquid and gaseous  Hydrocarbons  and
the  gathering,  processing,  transmission  and  marketing of  Hydrocarbons  and
activities related or ancillary thereto.

                                   ARTICLE VI
                               NEGATIVE COVENANTS

     Until the  Commitments  have expired or terminated and the principal of and
interest on each Loan and all fees payable  hereunder have been paid in full and
all Letters of Credit have expired or terminated and all LC Disbursements  shall
have been reimbursed, the Borrower covenants and agrees with the Lenders that:

     Section 6.01  Indebtedness.  The Borrower will not, and will not permit any
Restricted Subsidiary to, create, incur, assume or permit to exist (collectively
"incur") any Indebtedness if the Borrower would be in breach of any covenant set
forth in Section 6.04 as a result of such incurrence.

                                       44




                                                               December 16, 2003


     Section  6.02  Liens.  The  Borrower  will  not,  and will not  permit  any
Restricted  Subsidiary to, create,  incur, assume or permit to exist any Lien on
any property or asset now owned or  hereafter  acquired by it, or assign or sell
any income or revenues (including  accounts  receivable) or rights in respect of
any thereof, except:

     (a) Permitted Encumbrances;

     (b) any Lien on any  property or asset of the  Borrower  or any  Restricted
Subsidiary  existing on the date hereof and set forth in Schedule 6.02; provided
that  (i) such  Lien  shall  not  apply to any  other  property  or asset of the
Borrower or any Restricted Subsidiary and (ii) such Lien shall secure only those
obligations  which it secures on the date hereof and  extensions,  renewals  and
replacements  thereof  that do not  increase the  outstanding  principal  amount
thereof;

     (c) any Lien on any  property or asset  existing  prior to the  acquisition
thereof by the  Borrower or any  Subsidiary  or on any  property or asset of any
Person that becomes a  Subsidiary  after the date hereof  existing  prior to the
time such Person becomes a Restricted Subsidiary; provided that (i) such Lien is
not created in  contemplation  of or in connection with such acquisition or such
Person becoming a Subsidiary, as the case may be, (ii) such Lien shall not apply
to any other  property or assets of the Borrower or any  Restricted  Subsidiary,
and (iv) such Lien shall secure only those  obligations  which it secures on the
date of such  acquisition or the date such Person  becomes a Subsidiary,  as the
case  may be and  extensions,  renewals  and  replacements  thereof  that do not
increase the outstanding principal amount thereof;

     (d)  Liens  created  in  connection  with  the  acquisition,   development,
construction  or  improvement  by the Borrower or any  Restricted  Subsidiary of
fixed or  capital  assets;  provided  that (i) such  Liens  secure  Indebtedness
permitted by Section  6.01 and all  Indebtedness  secured by Liens  permitted by
this clause does not exceed  $100,000,000  in the aggregate  outstanding  at any
time, (ii) such Liens and the Indebtedness secured thereby are incurred prior to
or within 180 days after such acquisition or the completion of such development,
construction or  improvement,  (iii) the  Indebtedness  secured thereby does not
exceed 100% of the cost of acquiring, developing, constructing or improving such
fixed or capital  assets and (iv) such Liens shall not apply to any  property or
assets of the  Borrower or any  Restricted  Subsidiary  other than such fixed or
capital assets so acquired,  developed,  constructed or improved and other fixed
or capital assets that are developed or improved thereby or otherwise reasonably
related  thereto (in the good faith  determination  of the Borrower) and working
capital assets related  thereto  (including but not limited to revenue from, and
insurance,  condemnation,  sale and other proceeds of, any such fixed or capital
assets); and extensions,  renewals and replacements thereof that do not increase
the outstanding principal amount thereof.

     (e) Liens securing obligations owing under this Agreement; and

     (f) Liens on deposits  pursuant to any Swap  Agreement  entered into by the
Borrower or any  Restricted  Subsidiary in the ordinary  course of its business,
not to exceed $100,000,000 in the aggregate amount outstanding at any time.

                                       45




                                                               December 16, 2003


     Section 6.03     Fundamental Changes.

     (a) The Borrower  will not, and will not permit any  Subsidiary  Guarantors
to, merge into or consolidate with any other Person,  or permit any other Person
to merge into or consolidate  with it or liquidate or dissolve,  except that, if
at the time thereof and immediately after giving effect thereto no Default shall
have occurred and be continuing,  (i) any  Subsidiary  Guarantors may merge into
the  Borrower  in  a  transaction   in  which  the  Borrower  is  the  surviving
corporation,  (ii) any  Person  may merge into any  Subsidiary  Guarantors  in a
transaction  in  which  the  surviving  entity  is  a  wholly-owned   Subsidiary
Guarantor,  (iii) any Person may merge into the  Borrower  in a  transaction  in
which the surviving  entity is the Borrower and (iv) any  Subsidiary  Guarantors
may  liquidate  or dissolve if the Borrower  determines  in good faith that such
liquidation  or  dissolution is in the best interests of the Borrower and is not
materially disadvantageous to the Lenders.

     (b) The Borrower will not sell, transfer, lease or otherwise dispose of (in
one transaction or in a series of transactions)  all or substantially all of its
assets,  or all or substantially  all of the stock of the Subsidiary  Guarantors
(in each case,  whether now owned or hereafter  acquired)  other than to another
Subsidiary Guarantor.

     Section 6.04     Financial Covenants.

     (a) Prior to the Investment  Grade Date,  the Borrower will not permit,  at
any time, the ratio of the PV to Total Debt to be less than 1.25 to 1.0.

     (b) The Borrower shall not permit,  at any time, the ratio of Total Debt to
Total Cap to be greater than 0.60 to 1.0.

     (c) The Borrower will not permit, as of the end of any fiscal quarter,  the
ratio  of the  Borrower's  Consolidated  EBITDAX  to its  Consolidated  Interest
Expense for the four fiscal  quarters ending on such date to be less than 3.5 to
1.0.

     Section 6.05 Investments,  Loans, Advances, Guarantees and Acquisitions.(a)
The Borrower will not, and will not permit any of its Restricted Subsidiaries to
make any  loans or  advances  to,  Guarantee  any  obligations  of,  or make any
investment or any other interest in, any Unrestricted  Subsidiaries  except that
the Borrower or any  Restricted  Subsidiaries  may make loans or advances to, or
investments or other  interests in  Unrestricted  Subsidiaries if at the time of
the making of such loan,  advance,  investment  or other  interest the aggregate
book value of assets  (plus the  aggregate  amount of any  non-cash  write downs
therein under Statements of Financial  Accounting Standard Nos. 19, 109, 142 and
144 (and any statements replacing, modifying, or superceding any such Statement)
after  December  31,  2002,  net of  associate  taxes) of the  Borrower  and its
Restricted  Subsidiaries  on a  consolidated  basis  (excluding  investments  in
Unrestricted Subsidiaries) exceeds $2,750,000,000.

     (b)  No  Subsidiary  shall  Guarantee  any  Indebtedness  included  in  the
definition  of Total  Debt  unless  it shall  have  previously  or  concurrently
therewith  executed and  delivered a Subsidiary  Guaranty to the  Administrative
Agent together with the items in Sections  4.01(c) and (d) as to such Subsidiary
Guarantor and the Subsidiary Guaranty.

                                       46




                                                               December 16, 2003


     Section 6.06 Swap  Agreements.  The Borrower  will not, and will not permit
any of its Restricted Subsidiaries to, enter into any Swap Agreement, except (a)
Swap Agreements entered into to hedge or mitigate risks to which the Borrower or
any Restricted  Subsidiary has actual or projected exposure (other than those in
respect of Equity  Interests  of the Borrower or any of its  Subsidiaries),  (b)
Swap  Agreements  entered into in order to effectively  cap,  collar or exchange
interest rates (from fixed to floating rates,  from one floating rate to another
floating rate or otherwise)  with respect to any  interest-bearing  liability or
investment  of the  Borrower  or any  Restricted  Subsidiary  and (c) other Swap
Agreements  permitted  under  the  risk  management  policies  approved  by  the
Borrower's  Board of Directors from time to time and not subjecting the Borrower
and its Restricted Subsidiaries to material speculative risks.

     Section 6.07 Transactions with Affiliates.  The Borrower will not, and will
not permit any of its  Restricted  Subsidiaries  to,  sell,  lease or  otherwise
transfer any property or assets to, or purchase,  lease or otherwise acquire any
property or assets from, or otherwise engage in any other transactions with, any
of its Affiliates,  except (a) transfers on fair and reasonable  terms,  and (b)
transactions  between  or among the  Borrower  and its  wholly-owned  Restricted
Subsidiaries not involving any other Affiliate.

     Section 6.08  Restrictive  Agreements.  The Borrower will not, and will not
permit any of its Restricted  Subsidiaries  to,  directly or  indirectly,  enter
into,  incur or  permit  to  exist  any  agreement  or  other  arrangement  that
prohibits, restricts or imposes any condition upon the ability of any Restricted
Subsidiary to pay dividends or other distributions with respect to any shares of
its capital  stock or to make or repay loans or advances to the  Borrower or any
other Restricted Subsidiary or to Guarantee  Indebtedness of the Borrower or any
other Restricted Subsidiary;  provided that (i) the foregoing shall not apply to
restrictions  and  conditions  imposed  by law or by this  Agreement,  (ii)  the
foregoing  shall not apply to restrictions  and conditions  existing on the date
hereof  identified on Schedule 6.08 (but shall apply to any extension or renewal
of,  or  any  amendment  or  modification  expanding  the  scope  of,  any  such
restriction or condition)  and (iii) the foregoing  shall not apply to customary
restrictions  and conditions  contained in agreements  relating to the sale of a
Subsidiary  pending such sale,  provided such  restrictions and conditions apply
only to the Subsidiary that is to be sold and such sale is permitted hereunder.

                                  ARTICLE VII
                                EVENTS OF DEFAULT

     If any of the following events ("Events of Default") shall occur:

     (a)  the  Borrower  shall  fail  to pay any  principal  of any  Loan or any
reimbursement  obligation in respect of any LC Disbursement when and as the same
shall become due and payable, whether at the due date thereof or at a date fixed
for prepayment thereof or otherwise;

     (b) the  Borrower  shall fail to pay any interest on any Loan or any fee or
any other  amount  (other  than an  amount  referred  to in  clause  (a) of this
Article) payable under this Agreement, when and as the same shall become due and
payable, and such failure shall continue unremedied for a period of five days;

     (c) any  representation  or warranty made or deemed made by or on behalf of
the  Borrower  or  any  Subsidiary  Guarantor  in or  in  connection  with  this
Agreement,  any Subsidiary  Guaranty or any amendment or modification  hereof or
waiver  hereunder  or  thereunder,  or in  any  report,  certificate,  financial
statement or other  document  furnished  pursuant to or in connection  with this

                                       47




                                                               December 16, 2003


Agreement,  any Subsidiary  Guaranty or any amendment or modification  hereof or
thereof or any waiver hereof or thereof,  shall prove to have been  incorrect in
any  material  respect  when made or deemed  made and  either  (1) an  Executive
Officer of Borrower had actual  knowledge that such  representation  or warranty
was false or  incorrect  in a material  respect when made or (2) if no Executive
Officer had such knowledge, such representation or warranty shall continue to be
false or incorrect in any material  respect  thirty (30) Business Days after the
earlier of an Executive  Officer of Borrower  obtaining actual knowledge thereof
or written  notice  thereof  shall have been sent to Borrower by  Administrative
Agent or by any Lender;

     (d) the Borrower  shall fail to observe or perform any covenant,  condition
or  agreement  contained  in  Section  5.02,  Section  5.03(with  respect to the
Borrower's existence), or Section 5.08 or in ARTICLE VI;

     (e) the  Borrower  or any  Subsidiary  Guarantor  shall  fail to observe or
perform any covenant,  condition or agreement contained in this Agreement or any
Subsidiary  Guaranty  (other than those  specified  in clause (a), (b) or (d) of
this Article), and such failure shall continue unremedied for a period of thirty
days after notice thereof from the  Administrative  Agent to the Borrower (which
notice will be given at the request of any Lender);

     (f) the  Borrower  or any  Restricted  Subsidiary  shall  fail to make  any
payment of principal or interest in respect of any Material  Indebtedness (other
than in respect of any Swap  Agreement),  when and as the same shall  become due
and  payable or any event or  condition  occurs  that  results  in any  Material
Indebtedness  (including in respect of any Swap Agreement) becoming due prior to
its  scheduled  maturity or that enables or permits the holder or holders of any
Material  Indebtedness  (other  than in  respect of any Swap  Agreement)  or any
trustee or agent on its or their behalf to cause such Material  Indebtedness  to
become due, or to require the prepayment,  repurchase,  redemption or defeasance
thereof,  prior to its scheduled maturity, and such event or condition continues
beyond any  applicable  period of grace  provided  therefor,  provided that this
clause (f) shall not apply to secured  Indebtedness that becomes due as a result
of the  voluntary  sale or transfer  of the  property  or assets  securing  such
Indebtedness to the extent such Indebtedness is paid when due;

     (g) any event or condition  occurs of the type  customarily  included as an
event of default under  International Swap Dealers Association master agreements
(with  respect  to  which  the  Borrower  or any  Restricted  Subsidiary  is the
defaulting  party) that enables or permits the holder or holders of any Material
Indebtedness  under a Swap  Agreement  to declare an early  termination  date or
otherwise cause such Material  Indebtedness to become due prior to its scheduled
maturity and such event or condition  continues beyond any applicable  period of
grace provided therefor, except where such event or condition is being contested
in good faith;

     (h) an involuntary proceeding shall be commenced or an involuntary petition
shall be filed  seeking  (i)  liquidation,  reorganization  or other  relief  in
respect of the  Borrower  or any  Restricted  Subsidiary  or its debts,  or of a
substantial part of its assets, under any Federal,  state or foreign bankruptcy,
insolvency,  receivership  or similar law now or hereafter in effect or (ii) the
appointment  of a receiver,  trustee,  custodian,  sequestrator,  conservator or
similar  official  for  the  Borrower  or  any  Restricted  Subsidiary  or for a
substantial  part of its  assets,  and,  in any such case,  such  proceeding  or
petition shall continue  undismissed for 60 days or an order or decree approving
or ordering any of the foregoing shall be entered;

                                       48




                                                               December 16, 2003


     (i)  the  Borrower  or any  Restricted  Subsidiary  shall  (i)  voluntarily
commence any proceeding or file any petition seeking liquidation, reorganization
or other  relief  under any Federal,  state or foreign  bankruptcy,  insolvency,
receivership  or similar law now or  hereafter  in effect,  (ii)  consent to the
institution  of, or fail to  contest  in a timely and  appropriate  manner,  any
proceeding or petition described in clause (h) of this Article,  (iii) apply for
or consent to the appointment of a receiver, trustee,  custodian,  sequestrator,
conservator or similar official for the Borrower or any Restricted Subsidiary or
for a substantial part of its assets, (iv) file an answer admitting the material
allegations  of a petition filed against it in any such  proceeding,  (v) make a
general  assignment for the benefit of creditors or (vi) take any action for the
purpose of effecting any of the foregoing;

     (j) the Borrower or any Restricted Subsidiary shall become unable, admit in
writing its inability or fail generally to pay its debts as they become due;

     (k) one or more  judgments for the payment of money in an aggregate  amount
in excess of $75,000,000 shall be rendered against the Borrower,  any Restricted
Subsidiary or any combination thereof and the same shall remain undischarged for
a period of 30 consecutive  days during which execution shall not be effectively
stayed, or any action shall be legally taken by a judgment creditor to attach or
levy  upon any  material  domestic  assets  of the  Borrower  or any  Restricted
Subsidiary to enforce any such judgment;

     (l) an ERISA Event shall have occurred that, in the opinion of the Required
Lenders,  when taken  together  with all other ERISA Events that have  occurred,
could reasonably be expected to result in a Material Adverse Effect; or

     (m) a Change in Control shall occur;

then,  and in every such event  (other than an event with  respect to an Obligor
described  in clause  (h) or (i) of this  Article),  and at any time  thereafter
during the continuance of such event, the  Administrative  Agent may, and at the
request of the Required Lenders shall, by notice to the Borrower, take either or
both of the following actions, at the same or different times: (i) terminate the
Commitments, and thereupon the Commitments shall terminate immediately, and (ii)
declare the Loans then  outstanding  to be due and payable in whole (or in part,
in which case any principal not so declared to be due and payable may thereafter
be declared to be due and payable),  and thereupon the principal of the Loans so
declared to be due and payable,  together with accrued  interest thereon and all
fees and other obligations of the Borrower accrued  hereunder,  shall become due
and payable immediately, without presentment, demand, protest or other notice of
any kind,  all of which are hereby  waived by the  Borrower;  and in case of any
event with respect to an Obligor described in clause (h) or (i) of this Article,
the  Commitments  shall  automatically  terminate and the principal of the Loans
then outstanding,  together with accrued interest thereon and all fees and other
obligations of the Borrower accrued hereunder,  shall  automatically  become due
and payable,  without presentment,  demand, protest or other notice of any kind,
all of which are hereby waived by the Borrower.

                                       49




                                                               December 16, 2003


                                  ARTICLE VIII
                            THE ADMINISTRATIVE AGENT

     Section  8.01  Administrative  Agent.  Each of the  Lenders and the Issuing
Banks  hereby  irrevocably  appoints the  Administrative  Agent as its agent and
authorizes  the  Administrative  Agent to take such actions on its behalf and to
exercise such powers as are delegated to the  Administrative  Agent by the terms
hereof,  together  with such  actions  and powers as are  reasonably  incidental
thereto.

     The bank serving as the Administrative  Agent hereunder shall have the same
rights  and  powers in its  capacity  as a Lender as any  other  Lender  and may
exercise the same as though it were not the Administrative  Agent, and such bank
and its Affiliates may accept deposits from, lend money to and generally  engage
in any kind of business with the Borrower or any  Subsidiary or other  Affiliate
thereof as if it were not the Administrative Agent hereunder.

     The  Administrative  Agent shall not have any duties or obligations  except
those  expressly  set forth  herein.  Without  limiting  the  generality  of the
foregoing, (a) the Administrative Agent shall not be subject to any fiduciary or
other  implied  duties,  regardless  of whether a Default  has  occurred  and is
continuing,  (b) the  Administrative  Agent  shall not have any duty to take any
discretionary action or exercise any discretionary  powers, except discretionary
rights and powers expressly contemplated hereby that the Administrative Agent is
required to exercise  in writing as  directed by the  Required  Lenders (or such
other  number or  percentage  of the  Lenders  as shall be  necessary  under the
circumstances  as provided in Section  9.02),  and (c) except as  expressly  set
forth herein, the Administrative Agent shall not have any duty to disclose,  and
shall not be liable for the failure to disclose, any information relating to the
Borrower or any of its  Subsidiaries  that is communicated to or obtained by the
bank serving as  Administrative  Agent or any of its Affiliates in any capacity.
The  Administrative  Agent shall not be liable for any action taken or not taken
by it with the consent or at the request of the Required  Lenders (or such other
number  or  percentage   of  the  Lenders  as  shall  be  necessary   under  the
circumstances  as provided  in Section  9.02) or in the absence of its own gross
negligence or willful misconduct.  The Administrative  Agent shall be deemed not
to have  knowledge of any Default  unless and until  written  notice  thereof is
given  to the  Administrative  Agent  by  the  Borrower  or a  Lender,  and  the
Administrative  Agent shall not be responsible for or have any duty to ascertain
or inquire  into (i) any  statement,  warranty or  representation  made in or in
connection with this Agreement, (ii) the contents of any certificate,  report or
other  document  delivered  hereunder  or  in  connection  herewith,  (iii)  the
performance or observance of any of the covenants,  agreements or other terms or
conditions set forth herein, (iv) the validity, enforceability, effectiveness or
genuineness of this Agreement or any other agreement, instrument or document, or
(v) the  satisfaction  of any  condition  set forth in Article  IV or  elsewhere
herein,  other  than to  confirm  receipt  of  items  expressly  required  to be
delivered to the Administrative Agent.

     The  Administrative  Agent shall be  entitled  to rely upon,  and shall not
incur any liability for relying upon, any notice, request, certificate, consent,
statement,  instrument,  document or other writing  believed by it to be genuine
and to have been signed or sent by the proper Person. The  Administrative  Agent
also may rely upon any statement  made to it orally or by telephone and believed

                                       50




                                                               December 16, 2003


by it to be made by the proper  Person,  and shall not incur any  liability  for
relying thereon.  The  Administrative  Agent may consult with legal counsel (who
may be counsel for the  Borrower),  independent  accountants  and other  experts
selected by it, and shall not be liable for any action  taken or not taken by it
in accordance with the advice of any such counsel, accountants or experts.

     The  Administrative  Agent may perform any and all its duties and  exercise
its rights and powers by or through any one or more sub-agents  appointed by the
Administrative  Agent.  The  Administrative  Agent  and any such  sub-agent  may
perform any and all its duties and exercise its rights and powers  through their
respective  Related  Parties.  The  exculpatory   provisions  of  the  preceding
paragraphs  shall apply to any such sub-agent and to the Related  Parties of the
Administrative Agent and any such sub-agent, and shall apply to their respective
activities in connection with the syndication of the credit facilities  provided
for herein as well as activities as Administrative Agent.

     Subject to the  appointment  and  acceptance of a successor  Administrative
Agent as provided in this paragraph,  the Administrative Agent may resign at any
time by notifying the Lenders, the Issuing Banks and the Borrower. Upon any such
resignation, the Required Lenders shall have the right, in consultation with the
Borrower,  to appoint a successor.  If no successor shall have been so appointed
by the Required Lenders and shall have accepted such appointment  within 30 days
after the retiring  Administrative  Agent gives notice of its resignation,  then
the retiring  Administrative Agent may, on behalf of the Lenders and the Issuing
Banks , appoint a successor  Administrative  Agent.  Upon the  acceptance of its
appointment as  Administrative  Agent  hereunder by a successor,  such successor
shall succeed to and become vested with all the rights,  powers,  privileges and
duties of the retiring  Administrative  Agent,  and the retiring  Administrative
Agent shall be discharged  from its duties and obligations  hereunder.  The fees
payable by the Borrower to a successor Administrative Agent shall be the same as
those payable to its predecessor  unless  otherwise  agreed between the Borrower
and such successor.  After the Administrative Agent's resignation hereunder, the
provisions  of this  Article and Section  9.03 shall  continue in effect for the
benefit  of  such  retiring  Administrative  Agent,  its  sub-agents  and  their
respective  Related  Parties in respect  of any  actions  taken or omitted to be
taken by any of them while it was acting as Administrative Agent.

     Each Lender  acknowledges  that it has,  independently and without reliance
upon the  Administrative  Agent or any other Lender and based on such  documents
and information as it has deemed  appropriate,  made its own credit analysis and
decision to enter into this  Agreement.  Each Lender also  acknowledges  that it
will,  independently and without reliance upon the  Administrative  Agent or any
other Lender and based on such  documents and  information as it shall from time
to time deem  appropriate,  continue to make its own  decisions in taking or not
taking action under or based upon this Agreement,  any related  agreement or any
document furnished hereunder or thereunder.

     Section 8.02 The  Co-Arrangers,  Joint  Bookrunners,  Syndication Agent and
Co-Documentation Agents The Co-Arrangers,  Joint Bookrunners,  Syndication Agent
and   Co-Documentation   Agents  shall  have  no  duties,   responsibilities  or
liabilities  under this Agreement and the other Loan Documents  other than their
duties,  responsibilities  and  liabilities  in their  capacity  as Lenders  (or
Issuing Bank, if applicable) hereunder.

                                       51




                                                               December 16, 2003


                                   ARTICLE IX
                                 MISCELLANEOUS

     Section   9.01   Notices.   Except  in  the  case  of  notices   and  other
communications  expressly  permitted  to be given by  telephone  (and subject to
paragraph (b) below), all notices and other  communications  provided for herein
shall be in writing and shall be delivered by hand or overnight courier service,
mailed by certified or registered mail or sent by telecopy, as follows:

     (a) if to the  Borrower,  to 5205  North  O'Connor  Boulevard,  Suite  900,
Irving,  Texas,  75039,  Attention  of  Timothy  L. Dove  (Facsimile  No.  (972)
969-3572);

     (b) if to the Administrative Agent, to JPMorgan Chase Bank, Loan and Agency
Services Group, 1111 Fannin Street, 10th Floor, Houston, Texas, 77002, Attention
of Ms. Janene English  (Facsimile No. (713)  427-6307),  with a copy to JPMorgan
Chase Bank, 600 Travis Street, 20th Floor,  Houston,  Texas 77002,  Attention of
Mr. Peter Licalzi (Facsimile No. (713) 216-4117);

     (c) if to the  Issuing  Banks,  to  JPMorgan  Chase Bank at the address set
forth in  paragraph  (b) above,  to Bank of America at its address (or  telecopy
number) set forth below

                           Bank of America, N.A.
                           Trade Finance Service Center
                           333 S. Beaudry Avenue
                           Mail Code:  CA9-703-19-23
                           Los Angeles, California 90017-1466
                           Attn:  Thelma Chan
                           Telephone:  (213) 345-0084
                           Fax:  (213) 345-6684

     (d) if to the Swingline Lenders,  to JPMorgan Chase Bank at the address set
forth in paragraph (b) above,  to Wachovia  Bank,  National  Association  at its
address (or telecopy number) set forth in its Administrative Questionnaire.

     (e) if to any other Lender,  to it at its address (or telecopy  number) set
forth in its Administrative Questionnaire.

     (f) Notices and communications to the Lenders hereunder may be delivered or
furnished by electronic  communications  pursuant to procedures  approved by the
Administrative  Agent;  provided that the  foregoing  shall not apply to notices
pursuant to Article II unless otherwise agreed by the  Administrative  Agent and
the  applicable  Lender.  The  Administrative  Agent or the Borrower may, in its
discretion,  agree to accept notices and other communications to it hereunder by
electronic  communications  pursuant to procedures approved by it; provided that
approval  of  such   procedures   may  be  limited  to  particular   notices  or
communications.

                                       52




                                                               December 16, 2003


     Any party hereto may change its address or telecopy  number for notices and
other communications hereunder by notice to the other parties hereto, or, in the
case of any Lender, to the  Administrative  Agent and the Borrower.  All notices
and other  communications  given to any  party  hereto  in  accordance  with the
provisions of this  Agreement  shall be deemed to have been given on the date of
receipt.

     Section 9.02     Waivers; Amendments.

     (a) No failure or delay by the  Administrative  Agent, the Issuing Banks or
any Lender in exercising any right or power  hereunder shall operate as a waiver
thereof, nor shall any single or partial exercise of any such right or power, or
any  abandonment  or  discontinuance  of steps to enforce such a right or power,
preclude  any other or further  exercise  thereof or the  exercise  of any other
right or power. The rights and remedies of the Administrative Agent, the Issuing
Banks and the Lenders  hereunder  are  cumulative  and are not  exclusive of any
rights or remedies that they would otherwise have. No waiver of any provision of
this  Agreement or consent to any departure by the Borrower  therefrom  shall in
any event be effective  unless the same shall be  permitted by paragraph  (b) of
this  Section,  and then such waiver or consent  shall be effective  only in the
specific  instance  and for the purpose for which  given.  Without  limiting the
generality  of the  foregoing,  the making of a Loan or  issuance of a Letter of
Credit shall not be construed as a waiver of any Default,  regardless of whether
the Administrative Agent, any Lender or the Issuing Banks may have had notice or
knowledge of such Default at the time.

     (b) Neither this Agreement, any provision hereof, nor any provisions of the
Subsidiary  Guaranties may be waived,  amended or modified except pursuant to an
agreement or agreements in writing entered into by the Borrower and the Required
Lenders or by the Borrower and the Administrative  Agent with the consent of the
Required  Lenders;  provided that no such agreement shall (i) increase or extend
the  Commitment of any Lender without the written  consent of such Lender,  (ii)
reduce the principal amount of any Loan or LC Disbursement or reduce the rate of
interest  thereon,  or reduce any fees  payable  hereunder,  without the written
consent of each Lender  affected  thereby,  (iii) postpone the scheduled date of
payment of the principal amount of any Loan or LC Disbursement,  or any interest
thereon, or any fees payable hereunder, or reduce the amount of, waive or excuse
any  such  payment,  or  postpone  the  scheduled  date  of  expiration  of  any
Commitment,  without the written consent of each Lender affected  thereby,  (iv)
change  Section 2.09 or Section  2.18(b) or (c) in a manner that would alter the
pro rata treatment of Lenders or pro rata sharing of payments  required thereby,
without the written consent of each Lender,  or (v) change any of the provisions
of this Section or the definition of "Required  Lenders" or any other  provision
hereof  specifying the number or percentage of Lenders required to waive,  amend
or modify any rights  hereunder or make any  determination  or grant any consent
hereunder,  without the written consent of each Lender; provided further that no
such agreement shall amend,  modify or otherwise  affect the rights or duties of
the  Administrative  Agent, the Issuing Banks or the Swingline Lenders hereunder
without the prior written consent of the Administrative Agent, the Issuing Banks
or the Swingline Lenders, as the case may be.

                                       53




                                                               December 16, 2003


     Section 9.03     Expenses; Indemnity; Damage Waiver.

     (a)  The  Borrower  shall  pay (i) all  reasonable  out-of-pocket  expenses
incurred by the  Administrative  Agent and the Co-Arranger and their Affiliates,
including the  reasonable  fees,  charges and  disbursements  of counsel for the
Administrative   Agent,  in  connection  with  the  syndication  of  the  credit
facilities  provided for herein,  the  preparation  and  administration  of this
Agreement and the  Subsidiary  Guaranties or any  amendments,  modifications  or
waivers of the provisions  hereof (whether or not the transactions  contemplated
hereby or  thereby  shall be  consummated),  (ii) all  reasonable  out-of-pocket
expenses  incurred  by the  Issuing  Banks  in  connection  with  the  issuance,
amendment,  renewal  or  extension  of any  Letter of Credit or any  demand  for
payment thereunder and (iii) all reasonable  out-of-pocket  expenses incurred by
the  Administrative  Agent,  the  Issuing  Banks or any  Lender,  including  the
reasonable fees, charges and disbursements of any counsel for the Administrative
Agent,  the Issuing Banks or any Lender,  in connection  with the enforcement or
protection of its rights in connection  with this  Agreement and the  Subsidiary
Guaranties,  including its rights under this Section,  or in connection with the
Loans made or Letters of Credit issued hereunder,  including all such reasonable
out-of-pocket   expenses   incurred   during  any  workout,   restructuring   or
negotiations  in respect of such  Loans or  Letters of Credit.  Attorneys'  fees
reimbursed by Borrower in  connection  with the matters under clause (iii) above
shall  be for a  single  law  firm  per  country  (unless  conflicts  (including
conflicts  between the  Administrative  Agent,  the  Co-Arrangers  and the other
Lenders as determined  in the  reasonable  discretion  of the Required  Lenders)
otherwise  prohibit  the  engagement  of a single law firm) plus a single  local
counsel in each jurisdiction where local counsel is reasonably required.

     (b) The Borrower  shall  indemnify the  Administrative  Agent,  the Issuing
Banks , each Lender and each Related Party of any of the foregoing Persons (each
such Person  being called an  "Indemnitee")  against,  and hold each  Indemnitee
harmless  from, any and all losses,  claims,  damages,  liabilities  and related
expenses,  including  the  reasonable  fees,  charges and  disbursements  of any
counsel  for any  Indemnitee,  incurred by or  asserted  against any  Indemnitee
arising  out of, in  connection  with,  or as a result of (i) the  execution  or
delivery of this Agreement or any agreement or instrument  contemplated  hereby,
the performance by the parties hereto of their respective  obligations hereunder
or the consummation of the Transactions or any other  transactions  contemplated
hereby,  (ii) any Loan or Letter of Credit or the use of the proceeds  therefrom
(including any refusal by the Issuing Banks to honor or demand for payment under
a Letter of Credit if the documents  presented in connection with such demand do
not strictly  comply with the terms of such Letter of Credit),  (iii) any actual
or alleged  presence or release of  Hazardous  Materials on or from any property
owned  or  operated  by  the  Borrower  or  any  of  its  Subsidiaries,  or  any
Environmental  Liability  related  in  any  way to  the  Borrower  or any of its
Subsidiaries, or (iv) any actual or prospective claim, litigation, investigation
or proceeding relating to any of the foregoing,  whether based on contract, tort
or any other theory and regardless of whether any Indemnitee is a party thereto;
provided that such indemnity  shall not, as to any  Indemnitee,  be available to
the extent that such losses,  claims,  damages,  liabilities or related expenses
are determined by a court of competent  jurisdiction by final and  nonappealable
judgment to have  resulted  from the gross  negligence,  willful  misconduct  or
breach of contractual undertaking of such Indemnitee.

     (c) To the extent that the Borrower fails to pay any amount  required to be
paid by it to the  Administrative  Agent,  the  Issuing  Banks or the  Swingline
Lenders under paragraph (a) or (b) of this Section, each Lender severally agrees
to pay to the Administrative  Agent, the Issuing Banks or the Swingline Lenders,

                                       54




                                                               December 16, 2003


as the case may be, such Lender's  Applicable  Percentage  (determined as of the
time that the applicable unreimbursed expense or indemnity payment is sought) of
such unpaid amount;  provided that the unreimbursed expense or indemnified loss,
claim, damage, liability or related expense, as the case may be, was incurred by
or asserted against the Administrative Agent, the Issuing Banks or the Swingline
Lenders in its capacity as such.

     (d) To the extent  permitted by  applicable  law,  the  Borrower  shall not
assert,  and hereby waives,  any claim against any Indemnitee,  on any theory of
liability, for special, indirect,  consequential or punitive damages (as opposed
to direct or actual damages)  arising out of, in connection with, or as a result
of, this  Agreement or any  agreement or  instrument  contemplated  hereby,  the
Transactions, any Loan or Letter of Credit or the use of the proceeds thereof.

     (e) All amounts due under this  Section  shall be payable not later than 30
days after written demand therefor.

     Section 9.04     Successors and Assigns.

     (a) The provisions of this Agreement shall be binding upon and inure to the
benefit  of the  parties  hereto and their  respective  successors  and  assigns
permitted  hereby  (including any Affiliates of the Issuing Banks that issue any
Letters of Credit),  except that (i) the  Borrower  may not assign or  otherwise
transfer any of its rights or  obligations  hereunder  without the prior written
consent of each Lender (and any attempted assignment or transfer by the Borrower
without  such  consent  shall be null and void) and (ii) no Lender may assign or
otherwise transfer its rights or obligations hereunder except in accordance with
this  Section.  Nothing  in this  Agreement,  expressed  or  implied,  shall  be
construed  to confer  upon any Person  (other  than the  parties  hereto,  their
respective  successors and assigns permitted hereby (including any Affiliates of
the Issuing Banks that issue any Letters of Credit), Participants (to the extent
provided  in  paragraph  (c) of  this  Section)  and,  to the  extent  expressly
contemplated  hereby, the Related Parties of each of the  Administrative  Agent,
the Issuing Banks and the Lenders) any legal or equitable right, remedy or claim
under or by reason of this Agreement.

     (b) (i) Subject to the conditions set forth in paragraph (b)(ii) below, any
Lender  may assign to one or more  assignees  all or a portion of its rights and
obligations  under this Agreement  (including all or a portion of its Commitment
and the Loans at the time  owing to it) with the  prior  written  consent  (such
consent not to be unreasonably withheld or delayed) of:

             (A) the Borrower, provided that no consent of the Borrower shall be
required for an  assignment to a Lender,  an Affiliate of a Lender,  an Approved
Fund or,  if an Event of  Default  has  occurred  and is  continuing,  any other
assignee; and

             (B) the  Administrative  Agent,  provided  that  no consent  of the
Administrative  Agent  shall be  required  for an  assignment  of any  Revolving
Commitment  to  an  assignee  that  is a  Lender  with  a  Revolving  Commitment
immediately prior to giving effect to such assignment.

                                       55




                                                               December 16, 2003


         (ii) Assignments  shall  be   subject  to   the  following   additional
conditions:

             (A) except in the case of an assignment to a Lender or an Affiliate
of a Lender or an  assignment  of the entire  remaining  amount of the assigning
Lender's Commitment or Loans of any Class, the amount of the Commitment or Loans
of the assigning  Lender subject to each such  assignment  (determined as of the
date the Assignment and Assumption  with respect to such assignment is delivered
to the  Administrative  Agent) shall not be less than $10,000,000 unless each of
the Borrower and the Administrative  Agent otherwise  consent,  provided that no
such  consent of the  Borrower  shall be  required  if an Event of  Default  has
occurred and is continuing;

             (B) each  partial assignment  shall be  made as  an assignment of a
proportionate  part of all the assigning  Lender's rights and obligations  under
this Agreement, provided that this clause shall not be construed to prohibit the
assignment  of a  proportionate  part of all the assigning  Lender's  rights and
obligations in respect of one Class of Commitments or Loans;

             (C) the parties to each assignment shall execute and deliver to the
Administrative  Agent an Assignment and  Assumption,  together with a processing
and recordation fee of $3,500; and

             (D) the assignee, if it shall not be a Lender, shall deliver to the
Administrative  Agent  an  Administrative  Questionnaire  and  comply  with  the
requirements of Section 2.17(e).


     For the purposes of this Section 9.04(b),  the term "Approved Fund" has the
following meaning:

     "Approved  Fund"  means any Person  (other than a natural  person)  that is
engaged in making,  purchasing,  holding or  investing in bank loans and similar
extensions  of  credit  in the  ordinary  course  of its  business  and  that is
administered or managed by (a) a Lender,  (b) an Affiliate of a Lender or (c) an
entity or an Affiliate of an entity that administers or manages a Lender.

         (iii) Subject to acceptance and recording thereof pursuant to paragraph
(b)(iv) of this  Section,  from and after the effective  date  specified in each
Assignment and Assumption the assignee  thereunder  shall be a party hereto and,
to the extent of the interest  assigned by such Assignment and Assumption,  have
the rights and obligations of a Lender under this  Agreement,  and the assigning
Lender  thereunder  shall,  to the  extent  of the  interest  assigned  by  such
Assignment and Assumption, be released from its obligations under this Agreement
(and, in the case of an Assignment and Assumption  covering all of the assigning
Lender's rights and obligations under this Agreement, such Lender shall cease to
be a party hereto but shall  continue to be entitled to the benefits of Sections
2.15,  2.16, 2.17 and 9.03). Any assignment or transfer by a Lender of rights or
obligations  under this  Agreement  that does not comply with this  Section 9.04
shall be treated for  purposes of this  Agreement  as a sale by such Lender of a
participation in such rights and obligations in accordance with paragraph (c) of
this Section.

                                       56




                                                               December 16, 2003


         (iv) The Administrative Agent,  acting for  this purpose as an agent of
the Borrower, shall maintain at one of its offices a copy of each Assignment and
Assumption  delivered to it and a register for the  recordation of the names and
addresses of the Lenders,  and the  Commitment  of, and principal  amount of the
Loans and LC  Disbursements  owing to, each Lender  pursuant to the terms hereof
from  time to time  (the  "Register").  The  entries  in the  Register  shall be
conclusive,  and the Borrower,  the Administrative Agent, Bank of America, N.A.,
as Issuing Bank, and the Lenders may treat each Person whose name is recorded in
the Register pursuant to the terms hereof as a Lender hereunder for all purposes
of this Agreement, notwithstanding notice to the contrary. The Register shall be
available for  inspection by the Borrower,  the Issuing Bank and any Lender,  at
any reasonable time and from time to time upon reasonable prior notice.

         (v) Upon  its receipt  of a  duly completed  Assignment and  Assumption
executed  by an  assigning  Lender and an  assignee,  the  assignee's  completed
Administrative  Questionnaire  (unless the  assignee  shall  already be a Lender
hereunder),  the processing and  recordation fee referred to in paragraph (b) of
this Section and any written  consent to such  assignment  required by paragraph
(b) of this Section,  the Administrative  Agent shall accept such Assignment and
Assumption  and record the  information  contained  therein in the Register.  No
assignment  shall be effective for purposes of this Agreement unless it has been
recorded in the Register as provided in this paragraph.

     (c) (i) Any  Lender  may,   without  the  consent  of  the  Borrower,   the
Administrative   Agent,  the  Issuing  Bank  or  the  Swingline  Lenders,   sell
participations  to one or more banks or other entities (a  "Participant") in all
or a portion of such  Lender's  rights  and  obligations  under  this  Agreement
(including  all or a  portion  of its  Commitment  and the  Loans  owing to it);
provided that (A) such Lender's  obligations  under this Agreement  shall remain
unchanged,  (B) such Lender shall remain solely responsible to the other parties
hereto  for the  performance  of such  obligations  and  (C) the  Borrower,  the
Administrative  Agent, the Issuing Banks and the other Lenders shall continue to
deal solely and  directly  with such  Lender in  connection  with such  Lender's
rights and  obligations  under  this  Agreement.  Any  agreement  or  instrument
pursuant to which a Lender sells such a  participation  shall  provide that such
Lender shall retain the sole right to enforce this  Agreement and to approve any
amendment,  modification or waiver of any provision of this Agreement;  provided
that such agreement or instrument may provide that such Lender will not, without
the consent of the Participant,  agree to any amendment,  modification or waiver
described in the first proviso to Section 9.02(b) that affects such Participant.
Subject to paragraph  (c)(ii) of this  Section,  the  Borrower  agrees that each
Participant shall be entitled to the benefits of Sections 2.15, 2.16 and 2.17 to
the  same  extent  as if it were a  Lender  and had  acquired  its  interest  by
assignment pursuant to paragraph (b) of this Section.

         (ii) A Participant shall not be entitled to receive any greater payment
under  Section 2.15 or Section 2.17 than the  applicable  Lender would have been
entitled to receive with respect to the participation  sold to such Participant,
unless  the  sale of the  participation  to such  Participant  is made  with the

                                       57




                                                               December 16, 2003


Borrower's prior written  consent.  A Participant that would be a Foreign Lender
if it were a Lender shall not be entitled to the benefits of Section 2.17 unless
the Borrower is notified of the participation  sold to such Participant and such
Participant  agrees,  for the benefit of the  Borrower,  to comply with  Section
2.17(e) as though it were a Lender.

     (d) Any Lender may at any time pledge or assign a security  interest in all
or any portion of its rights under this Agreement to secure  obligations of such
Lender,  including  without  limitation  any  pledge  or  assignment  to  secure
obligations  to a Federal  Reserve Bank, and this Section shall not apply to any
such pledge or assignment of a security  interest;  provided that no such pledge
or  assignment  of a security  interest  shall  release a Lender from any of its
obligations hereunder or substitute any such pledgee or assignee for such Lender
as a party hereto.

     Section 9.05  Survival.  All  covenants,  agreements,  representations  and
warranties  made  by  the  Borrower  herein  and in the  certificates  or  other
instruments  delivered in connection with or pursuant to this Agreement shall be
considered  to have been  relied  upon by the  other  parties  hereto  and shall
survive the execution and delivery of this Agreement and the making of any Loans
and issuance of any Letters of Credit,  regardless of any investigation  made by
any  such  other   party  or  on  its  behalf  and   notwithstanding   that  the
Administrative  Agent,  the  Issuing  Banks or any Lender may have had notice or
knowledge of any Default or incorrect representation or warranty at the time any
credit is  extended  hereunder,  and shall  continue in full force and effect as
long as the  principal of or any accrued  interest on any Loan or any fee or any
other  amount  payable  under this  Agreement is  outstanding  and unpaid or any
Letter of Credit is outstanding and so long as the Commitments  have not expired
or terminated.  The provisions of Sections 2.15, 2.16, 2.17 and 9.03 and Article
VIII  shall  survive  and  remain in full  force and  effect  regardless  of the
consummation  of the  transactions  contemplated  hereby,  the  repayment of the
Loans,  the  expiration  or  termination  of  the  Letters  of  Credit  and  the
Commitments or the termination of this Agreement or any provision hereof.

     Section 9.06 Counterparts;  Integration;  Effectiveness. This Agreement may
be  executed in  counterparts  (and by  different  parties  hereto on  different
counterparts), each of which shall constitute an original, but all of which when
taken  together  shall  constitute a single  contract.  This  Agreement  and any
separate letter  agreements  with respect to fees payable to the  Administrative
Agent  constitute the entire contract among the parties  relating to the subject
matter hereof and supersede any and all previous  agreements and understandings,
oral or written,  relating to the subject matter  hereof.  Except as provided in
Section 4.01,  this  Agreement  shall become  effective  when it shall have been
executed by the  Administrative  Agent and when the  Administrative  Agent shall
have  received  counterparts  hereof  which,  when  taken  together,   bear  the
signatures of each of the other parties hereto,  and thereafter shall be binding
upon and  inure to the  benefit  of the  parties  hereto  and  their  respective
successors and assigns.  Delivery of an executed counterpart of a signature page
of this  Agreement  by  telecopy  shall be  effective  as delivery of a manually
executed counterpart of this Agreement.

     Section  9.07  Severability.  Any  provision of this  Agreement  held to be
invalid,  illegal  or  unenforceable  in  any  jurisdiction  shall,  as to  such
jurisdiction,  be  ineffective to the extent of such  invalidity,  illegality or

                                       58




                                                               December 16, 2003


unenforceability without affecting the validity,  legality and enforceability of
the remaining provisions hereof; and the invalidity of a particular provision in
a  particular  jurisdiction  shall not  invalidate  such  provision in any other
jurisdiction.

     Section 9.08    Governing Law; Jurisdiction; Consent to Service of Process.

     (a) THIS  AGREEMENT  AND THE NOTES SHALL BE GOVERNED  BY, AND  CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF TEXAS EXCEPT TO THE EXTENT THAT UNITED
STATES FEDERAL LAW PERMITS ANY LENDER TO CONTRACT FOR, CHARGE, RECEIVE,  RESERVE
OR TAKE  INTEREST AT THE RATE ALLOWED BY THE LAWS OF THE STATE WHERE SUCH LENDER
IS LOCATED.  CHAPTER 346 OF THE TEXAS  FINANCE  CODE  (WHICH  REGULATES  CERTAIN
REVOLVING CREDIT LOAN ACCOUNTS AND REVOLVING TRI-PARTY ACCOUNTS) SHALL NOT APPLY
TO THIS AGREEMENT.

     (b) ANY LEGAL ACTION OR PROCEEDING WITH RESPECT TO THE LOAN DOCUMENTS SHALL
BE  BROUGHT  IN THE  COURTS  OF THE  STATE OF TEXAS OR OF THE  UNITED  STATES OF
AMERICA FOR THE SOUTHERN  DISTRICT OF TEXAS,  AND, BY EXECUTION  AND DELIVERY OF
THIS  AGREEMENT,  EACH  PARTY  HEREBY  ACCEPTS  FOR  ITSELF  AND (TO THE  EXTENT
PERMITTED BY LAW) IN RESPECT OF ITS PROPERTY, GENERALLY AND UNCONDITIONALLY, THE
JURISDICTION OF THE AFORESAID COURTS.  EACH PARTY HEREBY  IRREVOCABLY WAIVES ANY
OBJECTION,  INCLUDING,  WITHOUT LIMITATION, ANY OBJECTION TO THE LAYING OF VENUE
OR BASED ON THE GROUNDS OF FORUM NON  CONVENIENS,  WHICH IT MAY NOW OR HEREAFTER
HAVE TO THE  BRINGING  OF ANY  SUCH  ACTION  OR  PROCEEDING  IN SUCH  RESPECTIVE
JURISDICTIONS.  THIS SUBMISSION TO JURISDICTION  IS  NON-EXCLUSIVE  AND DOES NOT
PRECLUDE A PARTY FROM  OBTAINING  JURISDICTION  OVER ANOTHER  PARTY IN ANY COURT
OTHERWISE HAVING JURISDICTION.

     (c) EACH PARTY IRREVOCABLY CONSENTS TO THE SERVICE OF PROCESS OF ANY OF THE
AFOREMENTIONED  COURTS IN ANY SUCH ACTION OR PROCEEDING BY THE MAILING OF COPIES
THEREOF BY REGISTERED OR CERTIFIED MAIL,  POSTAGE PREPAID,  TO IT AT THE ADDRESS
SPECIFIED  IN Section  9.01 OR SUCH OTHER  ADDRESS AS IS  SPECIFIED  PURSUANT TO
Section  9.01  (OR ITS  ASSIGNMENT  AND  ASSUMPTION),  SUCH  SERVICE  TO  BECOME
EFFECTIVE  THIRTY (30) DAYS AFTER SUCH MAILING.  NOTHING HEREIN SHALL AFFECT THE
RIGHT OF A PARTY OR ANY HOLDER OF A NOTE TO SERVE  PROCESS  IN ANY OTHER  MANNER
PERMITTED BY LAW OR TO COMMENCE LEGAL  PROCEEDINGS OR OTHERWISE  PROCEED AGAINST
ANOTHER PARTY IN ANY OTHER JURISDICTION.

     Section 9.09 WAIVER OF JURY TRIAL.  EACH PARTY HEREBY (i)  IRREVOCABLY  AND
UNCONDITIONALLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY LAW, TRIAL BY JURY IN
ANY LEGAL ACTION OR PROCEEDING  RELATING TO THIS AGREEMENT OR ANY OTHER DOCUMENT
RELATED TO THIS AGREEMENT AND FOR ANY  COUNTERCLAIM  THEREIN;  (ii)  IRREVOCABLY
WAIVES,  TO THE MAXIMUM  EXTENT NOT  PROHIBITED BY LAW, ANY RIGHT IT MAY HAVE TO

                                       59




                                                               December 16, 2003


CLAIM OR RECOVER IN ANY SUCH  LITIGATION  ANY  SPECIAL,  EXEMPLARY,  PUNITIVE OR
CONSEQUENTIAL DAMAGES, OR DAMAGES OTHER THAN, OR IN ADDITION TO, ACTUAL DAMAGES;
(iii) CERTIFIES THAT NO PARTY HERETO NOR ANY  REPRESENTATIVE OR AGENT OR COUNSEL
FOR ANY PARTY HERETO HAS  REPRESENTED,  EXPRESSLY OR OTHERWISE,  OR IMPLIED THAT
SUCH PARTY WOULD NOT, IN THE EVENT OF LITIGATION,  SEEK TO ENFORCE THE FOREGOING
WAIVERS,  AND (iv)  ACKNOWLEDGES  THAT IT HAS BEEN  INDUCED  TO ENTER  INTO THIS
AGREEMENT,  THE LOAN  DOCUMENTS  AND THE  TRANSACTIONS  CONTEMPLATED  HEREBY AND
THEREBY BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS  CONTAINED
IN THIS Section 9.09.

     Section  9.10  Headings.  Article  and  Section  headings  and the Table of
Contents used herein are for convenience of reference only, are not part of this
Agreement  and  shall  not  affect  the   construction  of,  or  be  taken  into
consideration in interpreting, this Agreement.

     Section 9.11 Confidentiality. Each of the Administrative Agent, the Issuing
Banks and the Lenders agrees to maintain the  confidentiality of the Information
(as defined below),  except that Information may be disclosed (a) to its and its
Affiliates' directors, officers, employees and agents, including accountants and
legal counsel (it being  understood  that the Persons to whom such disclosure is
made  will be  informed  of the  confidential  nature  of such  Information  and
instructed to keep such Information  confidential),  (b) to the extent requested
by any  regulatory  authority  or any  self-regulatory  body  claiming  to  have
authority,  (c) to the extent  required by applicable  laws or regulations or by
any subpoena or similar legal  process or  authority,  (d) to any other party to
this Agreement, (e) in connection with the exercise of any remedies hereunder or
any suit, action or proceeding  relating to this Agreement or the enforcement of
rights   hereunder,   (f)  subject  to  an   agreement   containing   provisions
substantially  the same as  those of this  Section,  to (i) any  assignee  of or
Participant  in, or any  prospective  assignee of or Participant  in, any of its
rights or  obligations  under this  Agreement,  (ii) any  actual or  prospective
counterparty (or its advisors) to any swap or derivative transaction relating to
the  Borrower  and its  obligations,  or (iii) to its  advisors  (other than its
accountants and legal  counsel),  (g) with the consent of the Borrower or (h) to
the extent such Information becomes publicly available other than as a result of
a breach of this Section. For the purposes of this Section,  "Information" means
all  information  received  from the  Borrower  relating to the  Borrower or its
business,   other  than  any  such   information   that  is   available  to  the
Administrative Agent, the Issuing Banks or any Lender on a nonconfidential basis
prior to  disclosure  by the Borrower.  Notwithstanding  anything  herein to the
contrary,  any party to this Agreement (and any employees,  representatives  and
other  agents  of such  party)  may  disclose  to any and all  persons,  without
limitation of any kind (a) any information  with respect to the U.S. federal and
state income tax treatment of the transactions contemplated herein and any facts
that may be relevant to understanding such tax treatment,  which facts shall not
include  for this  purpose the names of the  parties or any other  person  named
herein,  or information that would permit  identification of the parties or such
other  persons,  or any pricing terms or other  nonpublic  business or financial
information  that is  unrelated  to such tax  treatment  or  facts,  and (b) all
materials of any kind  (including  opinions or other tax  analyses)  relating to
such tax treatment or facts that are provided to any of the persons  referred to
above.

                                       60




                                                               December 16, 2003


     Section 9.12 Interest Rate  Limitation.  It is the intention of the parties
hereto that each Lender shall conform  strictly to usury laws  applicable to it.
Accordingly, if the transactions contemplated hereby would be usurious as to any
Lender under laws  applicable to it (including  the laws of the United States of
America  and the  State of Texas or any  other  jurisdiction  whose  laws may be
mandatorily  applicable to such Lender  notwithstanding  the other provisions of
this Agreement),  then, in that event,  notwithstanding anything to the contrary
in the Agreement or the Subsidiary Guaranties,  it is agreed as follows: (i) the
aggregate of all consideration  which constitutes  interest under law applicable
to any Lender that is contracted  for, taken,  reserved,  charged or received by
such Lender under the  Agreement  or the  Subsidiary  Guaranties  shall under no
circumstances  exceed the maximum amount allowed by such applicable law, and any
excess shall be canceled automatically and if theretofore paid shall be credited
by such Lender on the principal  amount of the  Indebtedness  (or, to the extent
that the principal amount of the  Indebtedness  shall have been or would thereby
be paid in full, refunded by such Lender to the Borrower); and (ii) in the event
of  any  required  or  permitted   prepayment,   then  such  consideration  that
constitutes  interest  under law applicable to any Lender may never include more
than the maximum amount allowed by such applicable law, and excess interest,  if
any, provided for in this Agreement or otherwise shall be canceled automatically
by such  Lender  as of the  date of such  acceleration  or  prepayment  and,  if
theretofore  paid,  shall be credited by such Lender on the principal  amount of
the  Indebtedness   (or,  to  the  extent  that  the  principal  amount  of  the
Indebtedness shall have been or would thereby be paid in full,  refunded by such
Lender to the  Borrower).  All sums paid or agreed to be paid to any  Lender for
the use,  forbearance  or detention of sums due hereunder  shall,  to the extent
permitted by law applicable to such Lender,  be amortized,  prorated,  allocated
and spread throughout the stated term of the Loans until payment in full so that
the rate or amount of interest on account of any Loans hereunder does not exceed
the maximum amount allowed by such  applicable law. If at any time and from time
to time (i) the  amount of  interest  payable to any Lender on any date shall be
computed at the Highest Lawful Rate  applicable to such Lender  pursuant to this
Section 9.12 and (ii) in respect of any subsequent  interest  computation period
the amount of interest  otherwise  payable to such Lender would be less than the
amount of interest  payable to such Lender  computed at the Highest  Lawful Rate
applicable to such Lender, then the amount of interest payable to such Lender in
respect of such  subsequent  interest  computation  period shall  continue to be
computed at the Highest  Lawful Rate  applicable  to such Lender until the total
amount of  interest  payable  to such  Lender  shall  equal the total  amount of
interest  which would have been  payable to such  Lender if the total  amount of
interest had been  computed  without  giving effect to this Section 9.12. To the
extent that Chapter 303 of the Texas Finance Code is relevant for the purpose of
determining the Highest Lawful Rate  applicable to a Lender,  such Lender elects
to  determine  the  applicable  rate  ceiling  under such  Chapter by the weekly
ceiling from time to time in effect.  Chapter 346 of the Texas Finance Code does
not apply to the Borrower's obligations hereunder.

     Section  9.13 USA Patriot  Act Notice.  Each  Lender  hereby  notifies  the
Borrower that pursuant to the  requirements of the USA Patriot Act (Title III of
Pub. L. 107-56  (signed into law October 26, 2001)) (the "Act"),  it is required
to obtain,  verify and record  information  that identifies the Borrower,  which
information  includes the name and address of the Borrower and other information
that will allow such Lender to identify the Borrower in accordance with the Act.

                                       61




                                                               December 16, 2003



                        [SIGNATURE PAGES BEGIN NEXT PAGE]




                                       62





                                                               December 16, 2003


     IN WITNESS  WHEREOF,  the parties  hereto have caused this  Agreement to be
duly  executed by their  respective  authorized  officers as of the day and year
first above written.

Borrower:                              PIONEER NATURAL RESOURCES
                                       COMPANY



                                       By:
                                           -----------------------------
                                           Timothy L. Dove
                                           Executive Vice President and
                                           Chief Financial Officer





                                Signature Page 1




                                                               December 16, 2003

      Administrative Agent & Lender:              JPMORGAN CHASE BANK



                                                  By:
                                                      -------------------------
                                                  Name:  Robert C. Mertensotto
                                                  Title: Managing Director



                                Signature Page 2




                                                               December 16, 2003


Co-Arranger:                                     J.P. MORGAN SECURITIES INC.




                                                 By:
                                                      -------------------------
                                                 Name:
                                                       ------------------------
                                                 Title:
                                                       ------------------------


                                Signature Page 3




                                                               December 16, 2003




Co-Arranger:                                  WACHOVIA CAPITAL MARKETS, LLC




                                               By:
                                                   ----------------------------
                                               Name:  David Humphreys
                                               Title: Vice President




                                Signature Page 4






                                                               December 16, 2003


Syndication Agent & Lender:                     WACHOVIA BANK, NATIONAL
                                                ASSOCIATION



                                                By:
                                                    ---------------------------
                                                Name:  David Humphreys
                                                Title: Vice President



                                Signature Page 5





                                                               December 16, 2003


Documentation Agent & Lender:                   BANK OF AMERICA, N.A.



                                                By:
                                                    --------------------------
                                                    Name:  Ronald E. McKaig
                                                    Title: Managing Director



                                Signature Page 6





                                                               December 16, 2003


Documentation Agent & Lender:              BANK ONE, N.A. (MAIN OFFICE CHICAGO)




                                           By:
                                               -------------------------------
                                               Name:  J. Scott Fowler
                                               Title: Director, Capital Markets



                                Signature Page 7





                                                               December 16, 2003



Documentation Agent & Lender:               FLEET NATIONAL BANK



                                            By:
                                                -------------------------------
                                                Name:  Jeffrey H. Rathkamp
                                                Title: Director




                                Signature Page 8






                                                               December 16, 2003


Documentation Agent & Lender:                      WELLS FARGO BANK, NATIONAL
                                                   ASSOCIATION



                                                   By:
                                                      -------------------------
                                                      Name:  David C. Brooks
                                                      Title: Vice President



                                Signature Page 9





                                                               December 16, 2003


Lenders:                                           ABN AMRO



                                                   By:
                                                       ------------------------
                                                       Name:  Frank Russo
                                                       Title: Vice President



                                                   By:
                                                       ------------------------
                                                       Name:  John Reed
                                                       Title: Vice President



                               Signature Page 10





                                                               December 16, 2003



                                                   CITIBANK, N.A.




                                                   By:
                                                       ------------------------
                                                       Name:  Joronne Jeter
                                                       Title: Attorney-In-Fact



                               Signature Page 11






                                                               December 16, 2003


                                   CREDIT AGRICOLE INDOSUEZ



                                   By:
                                       -------------------------
                                       Name:  Thomas P. Gillis
                                       Title: Senior Vice President
                                              Head of Banking Division
                                              General, Manager, Chicago Branch


                                   By:
                                       -------------------------
                                       Name: Gerard M. Russell
                                       Title: Vice President, Manager


                               Signature Page 12






                                                               December 16, 2003


                                        CREDIT SUISSE FIRST BOSTON
                                        acting through its Cayman Islands Branch




                                        By:
                                            -----------------------------------
                                            Name:  James P. Moran
                                            Title: Director


                                        By:
                                            -----------------------------------
                                            Name:  Denise L. Alvarez
                                            Title: Associate




                               Signature Page 13







                                                               December 16, 2003



                                            DEUTSCHE BANK AG NEW YORK BRANCH



                                            By:
                                                -------------------------------
                                                Name:  Joel Makowsky
                                                Title: Director



                                            By:
                                                -------------------------------
                                                Name:  Oliver Riedinger
                                                Title: Vice President



                               Signature Page 14





                                                               December 16, 2003



                                                THE BANK OF NOVA SCOTIA



                                                By:
                                                    ---------------------------
                                                    Name:  William E. Zarrett
                                                    Title: Managing Director



                                                SCOTIABANC INC.



                                                By:
                                                    ---------------------------
                                                    Name:  William E. Zarrett
                                                    Title: Managing Director



                               Signature Page 15





                                                               December 16, 2003


                                                 SUNTRUST BANK



                                                 By:
                                                     --------------------------
                                                     Name:  James M. Warren
                                                     Title: Director




                               Signature Page 16







                                                               December 16, 2003



                                                 UNION BANK OF CALIFORNIA, N.A.




                                                 By:
                                                      -------------------------
                                                 Name:
                                                       ------------------------
                                                 Title:
                                                       ------------------------



                               Signature Page 17







                                                               December 16, 2003


                                                 BARCLAYS BANK PLC



                                                 By:
                                                     --------------------------
                                                     Name:  Nicholas A. Bell
                                                     Title: Director



                               Signature Page 18






                                                               December 16, 2003



                                                BNP PARIBAS



                                                By:
                                                    ---------------------------
                                                    Name:  David Dodd
                                                    Title: Director



                                                By:
                                                    ---------------------------
                                                    Name:  Betsy Jocher
                                                    Title: Vice President



                               Signature Page 19






                                                               December 16, 2003



                                               THE BANK OF NEW YORK



                                               By:
                                                   ----------------------------
                                                   Name:  Craig J. Anderson
                                                   Title: Vice President




                               Signature Page 20







                                                               December 16, 2003



                                                Den norske Bank ASA



                                                By:
                                                    ---------------------------
                                                    Name:  Peter M. Dodge
                                                    Title: First Vice President


                                                By:
                                                    ---------------------------
                                                    Name:  Nils Fykse
                                                    Title: Senior Vice President



                               Signature Page 21






                                                               December 16, 2003


                                                MIZUHO CORPORATE BANK, LTD



                                                By:
                                                    ---------------------------
                                                    Name:  Akihiko Mabuchi
                                                    Title: Senior Vice President



                               Signature Page 22






                                                               December 16, 2003


                                                U.S. BANK NATIONAL ASSOCIATION



                                                By:
                                                    ---------------------------
                                                    Name:  Mark E. Thompson
                                                    Title: Vice President



                               Signature Page 23






                                                               December 16, 2003


                                                WASHINGTON MUTUAL BANK, F.A.



                                                By:
                                                    ---------------------------
                                                    Name:  Mark Isensee
                                                    Title: Vice President



                               Signature Page 24






                                                               December 16, 2003


                                                AUSTRALIA AND NEW ZEALAND
                                                BANKING GROUP LIMITED


                                                By:
                                                    ---------------------------
                                                    Name:  R. Scott McInnis
                                                    Title: Country Head - USA



                               Signature Page 25






                                                               December 16, 2003


                                               BMO NESBITT BURNS FINANCING, INC.



                                               By:
                                                   ----------------------------
                                                   Name:  James V. Ducote
                                                   Title: Vice President



                               Signature Page 26






                                                               December 16, 2003


                                               KBC BANK N.V.



                                               By:
                                                   ----------------------------
                                                   Name:  Robert Snauffer
                                                   Title: First Vice President



                                               By:
                                                   ----------------------------
                                                   Name:  William Cavanaugh
                                                   Title: Vice President



                               Signature Page 27






                                                               December 16, 2003


                                               TORONTO DOMINION (TEXAS), INC.



                                               By:
                                                   ----------------------------
                                                   Name:  Mark A. Baird
                                                   Title: Vice President



                               Signature Page 28






                                                               December 16, 2003


                                              UFJ BANK LIMITED



                                              By:
                                                  -----------------------------
                                                  Name:  Clyde L. Redford
                                                  Title: Senior Vice President



                               Signature Page 29






                                                               December 16, 2003


                                  SCHEDULE 1.01

                           EXISTING LETTERS OF CREDIT


1.       Issuing Bank:           Bank of America
         Beneficiary:            Acstar Insurance Company
         Amount:                      $150,000
         Date of Issue:          9/15/94
         Expiration:             9/15/04

2.       Issuing Bank:           Bank of America
         Beneficiary:            Chevron USA Inc
         Amount:                      $7,000,000
         Date of Issue:          6/17/98
         Expiration:             6/1/04

3.       Issuing Bank:           Bank of America
         Beneficiary:            Chevron USA Inc
         Amount:                      $7,000,000
         Date of Issue:          6/17/98
         Expiration:             6/1/04

4.       Issuing Bank:           Bank of America
         Beneficiary:            Bank of Nova Scotia Trust Company of  New York
         Amount:                      $13,852,000
         Date of Issue:          5/30/00
         Expiration:             5/30/04

5.       Issuing Bank:           Bank of America
         Beneficiary:            Citibank, N.A. Gabon BP
         Amount:                      $150,000
         Date of Issue:          5/02/2002
         Expiration:             12/31/2004

6.       Issuing Bank:           Bank of America
         Beneficiary:            Alliance Canadian Marketing LP
         Amount:                      $655,000
         Date of Issue:          1/13/2003
         Expiration:             12/31/2003




                                 Schedule 1.01




                                                               December 16, 2003



                                  SCHEDULE 2.01
                                   COMMITMENTS





                    Lender                          Amount of Commitment     Percentage of Total
                                                                                 Commitments
- -----------------------------------------------     --------------------     -------------------

                                                                              
JPMorgan Chase Bank                                     $42,500,000                 6.075%
Wachovia Bank, National Association                     $42,500,000                 6.075%
Wells Fargo Bank, National Association                  $40,000,000                 5.715%
Bank of America, N.A.                                   $40,000,000                 5.715%
Bank One, N.A. (Main Office Chicago)                    $40,000,000                 5.715%
Fleet National Bank                                     $40,000,000                 5.715%
ABN Amro                                                $30,000,000                 4.285%
Citibank, N.A.                                          $30,000,000                 4.285%
Credit Agricole Indosuez                                $30,000,000                 4.285%
Credit Suisse First Boston, acting through              $30,000,000                 4.285%
  its Cayman Islands Branch
Deutsche Bank AG New York Branch                        $30,000,000                 4.285%
The Bank of Nova Scotia                                 $15,000,000                 2.145%
Scotiabank Inc.                                         $15,000,000                 2.145%
Suntrust Bank                                           $30,000,000                 4.285%
Union Bank of California, N.A.                          $30,000,000                 4.285%
Barclays Bank PLC                                       $20,000,000                 2.855%
BNP Paribas                                             $20,000,000                 2.855%
The Bank of New York                                    $20,000,000                 2.855%
Den norske Bank ASA                                     $20,000,000                 2.855%
Mizuho Corporate Bank, Ltd.                             $20,000,000                 2.855%
U.S. Bank National Association                          $20,000,000                 2.855%
Washington Mutual Bank, F.A.                            $20,000,000                 2.855%
Australia and New Zealand Banking Group Limited         $15,000,000                 2.145%
BMO Nesbitt Burns Financing, Inc.                       $15,000,000                 2.145%
KBC Bank N.V.                                           $15,000,000                 2.145%
Toronto Dominion (Texas), Inc.                          $15,000,000                 2.145%
UFJ Bank Limited                                        $15,000,000                 2.145%

                                            Total:     $700,000,000                100.00%




                                 Schedule 2.01





                                                               December 16, 2003



                                  SCHEDULE 2.13

                         SWINGLINE LOAN RATE CALCULATION

The rate of  interest  for a  Swingline  Loan  shall be (a) the  "ASK"  rate for
Federal  Funds  appearing on Page 5 of the Dow Jones  Market  Service (or on any
successor or substitute page of such Service,  or any successor to or substitute
for such  Service,  providing  rate  quotations  comparable  to those  currently
provided on such page of such Service, as determined by the Administrative Agent
from time to time for  purposes  of  providing  quotations  of the  offer  rates
applicable to Federal Funds for a term of one Business Day) at the time reviewed
by the  Administrative  Agent plus (b) the Applicable  Margin for the Eurodollar
Spread.  In the event that part (a) of such rate is not  available  at such time
for any  reason,  then part (a) of such rate will be the rate  agreed to between
the Administrative  Agent and the Borrower.  The Borrower understands and agrees
that the rate quoted from Page 5 of the Dow Jones Market  Service is a real-time
rate that changes from time to time. The rate quoted by the Administrative Agent
and used for the purpose of setting the interest rate for a Swingline  Loan will
be the rate on the screen of the Administrative Agent at the time of setting the
rate and will not be an average or composite of rates for that day.




                                 Schedule 2.13





                                                               December 16, 2003


                                  SCHEDULE 3.06
                                DISCLOSED MATTERS




John Stephen Alford and Robert Larrabee, individually and on behalf of Plaintiff
Class v. Mesa Inc., Hugoton Capital Limited Partnership,  Mesa Operating Limited
Partnership,  No. 93 CV 37;  26th  District  Court of Stevens  County,  KS Civil
Department.

United States of America,  Federal Energy Regulatory  Commission,  Southern Star
Central Gas Pipeline, Inc. Docket Nos. RP98-52-051, et al. and Panhandle Eastern
Pipe Line Company, et al. Docket No. RP98-40 et al.




                                 Schedule 3.06








                                                               December 16, 2003



                                  SCHEDULE 6.02
                                      LIENS


                                      NONE





                                 Schedule 6.02







                                                               December 16, 2003



                                  SCHEDULE 6.08
                         EXISTING RESTRICTIVE AGREEMENTS



                                      NONE




                                 Schedule 6.08









                                    EXHIBIT A

                                     FORM OF

                            ASSIGNMENT AND ASSUMPTION


     This Assignment and Assumption (the  "Assignment and  Assumption") is dated
as of the  Effective  Date set forth  below and is entered  into by and  between
[Insert name of Assignor]  (the  "Assignor")  and [Insert name of Assignee] (the
"Assignee").  Capitalized  terms  used but not  defined  herein  shall  have the
meanings given to them in the Credit Agreement identified below (as amended, the
"Credit  Agreement"),  receipt of a copy of which is hereby  acknowledged by the
Assignee. The Standard Terms and Conditions set forth in Annex 1 attached hereto
are hereby  agreed to and  incorporated  herein by reference  and made a part of
this Assignment and Assumption as if set forth herein in full.

     For an agreed  consideration,  the Assignor  hereby  irrevocably  sells and
assigns to the  Assignee,  and the Assignee  hereby  irrevocably  purchases  and
assumes from the Assignor,  subject to and in accordance with the Standard Terms
and  Conditions and the Credit  Agreement,  as of the Effective Date inserted by
the Administrative  Agent as contemplated below (i) all of the Assignor's rights
and  obligations in its capacity as a Lender under the Credit  Agreement and any
other documents or instruments  delivered pursuant thereto to the extent related
to  the  amount  and  percentage  interest  identified  below  of  all  of  such
outstanding  rights  and  obligations  of  the  Assignor  under  the  respective
facilities  identified below (including any letters of credit,  guarantees,  and
swingline loans included in such facilities) and (ii) to the extent permitted to
be assigned under  applicable law, all claims,  suits,  causes of action and any
other right of the Assignor  (in its  capacity as a Lender)  against any Person,
whether  known or  unknown,  arising  under  or in  connection  with the  Credit
Agreement,  any other documents or instruments delivered pursuant thereto or the
loan  transactions  governed thereby or in any way based on or related to any of
the foregoing,  including  contract  claims,  tort claims,  malpractice  claims,
statutory  claims and all other claims at law or in equity related to the rights
and obligations  sold and assigned  pursuant to clause (i) above (the rights and
obligations  sold and  assigned  pursuant  to clauses  (i) and (ii) above  being
referred  to herein  collectively  as the  "Assigned  Interest").  Such sale and
assignment is without recourse to the Assignor and, except as expressly provided
in this Assignment and  Assumption,  without  representation  or warranty by the
Assignor.

1.   Assignor:               ______________________________

2.   Assignee:               ______________________________
                             [and is an Affiliate/Approved Fund of [identify
                             Lender]1]

3.   Borrower(s):            ______________________________

4.   Administrative Agent:   ______________________, as the administrative agent
                             under the Credit Agreement

__________________

1  Select as applicable.



                                  EXHIBIT A-1






5.   Credit Agreement:       [The  $700,000,000  Credit  Agreement  dated  as of
                             _______________  among [name  of Borrower(s)],  the
                             Lenders parties thereto,  JPMorgan Chase  Bank,  as
                             Administrative Agent,  and the other agents parties
                             thereto]





                                  EXHIBIT A-2







6. Assigned Interest:



- ---------------------  ---------------------  -----------------  ----------------------
Facility Assigned 2      Aggregate Amount of      Amount of      Percentage Assigned of
                       Commitment/Loans for   Commitment/Loans     Commitment/Loans 3
                             all Lenders           Assigned
- ---------------------  ---------------------  -----------------  ----------------------
                                                        
                       $                      $                                   %
- ---------------------  ---------------------  -----------------  ----------------------
                       $                      $                                   %
- ---------------------  ---------------------  -----------------  ----------------------
                       $                      $                                   %
- ---------------------  ---------------------  -----------------  ----------------------


Effective Date: _____________ ___, 20___ [TO BE INSERTED BY ADMINISTRATIVE AGENT
AND WHICH SHALL BE THE EFFECTIVE DATE OF RECORDATION OF TRANSFER IN THE REGISTER
THEREFOR.]

The terms set forth in this Assignment and Assumption are hereby agreed to:

                                             ASSIGNOR

                                             [NAME OF ASSIGNOR]


                                             By:
                                                 -----------------------------
                                                        Title:


                                             ASSIGNEE

                                             [NAME OF ASSIGNEE]


                                             By:
                                                 -----------------------------
                                                        Title:

_________________
2 Fill in the  appropriate  terminology  for the types of  facilities  under the
Credit Agreement that are being assigned under this Assignment (e.g., "Revolving
Commitment," "Tranche A. Commitment," "Tranche B Commitment," etc.)
3 Set forth, to at least 9 decimals,  as a percentage of the Commitment/Loans of
all Lenders thereunder.


                                  EXHIBIT A-3






Consented to and Accepted:

JPMORGAN CHASE BANK, as
  Administrative Agent


By
   --------------------------------
  Title:


Consented to:

[NAME OF RELEVANT PARTY]


By
   --------------------------------
  Title:



                                  EXHIBIT A-4





                                                                        ANNEX 1

                             [__________________]4

                        STANDARD TERMS AND CONDITIONS FOR
                            ASSIGNMENT AND ASSUMPTION

     1. Representations and Warranties.

     1.1 Assignor.  The Assignor (a)  represents and warrants that (i) it is the
legal and beneficial owner of the Assigned Interest,  (ii) the Assigned Interest
is free and clear of any lien,  encumbrance  or other adverse claim and (iii) it
has full power and authority, and has taken all action necessary, to execute and
deliver this  Assignment  and  Assumption  and to  consummate  the  transactions
contemplated  hereby; and (b) assumes no responsibility  with respect to (i) any
statements,  warranties or  representations  made in or in  connection  with the
Credit  Agreement  or any other Loan  Document,  (ii) the  execution,  legality,
validity,  enforceability,   genuineness,  sufficiency  or  value  of  the  Loan
Documents or any  collateral  thereunder,  (iii) the financial  condition of the
Borrower, any of its Subsidiaries or Affiliates or any other Person obligated in
respect  of any Loan  Document  or (iv) the  performance  or  observance  by the
Borrower,  any of its  Subsidiaries  or Affiliates or any other Person of any of
their respective obligations under any Loan Document.

     1.2.  Assignee.  The Assignee (a)  represents  and warrants that (i) it has
full power and  authority,  and has taken all action  necessary,  to execute and
deliver this  Assignment  and  Assumption  and to  consummate  the  transactions
contemplated  hereby and to become a Lender under the Credit Agreement,  (ii) it
satisfies the requirements,  if any,  specified in the Credit Agreement that are
required to be  satisfied  by it in order to acquire the  Assigned  Interest and
become a Lender,  (iii) from and after the Effective  Date, it shall be bound by
the provisions of the Credit Agreement as a Lender thereunder and, to the extent
of the Assigned  Interest,  shall have the  obligations of a Lender  thereunder,
(iv) it has received a copy of the Credit Agreement, together with copies of the
most recent financial  statements  delivered pursuant to Section ___ thereof, as
applicable,   and  such  other  documents  and  information  as  it  has  deemed
appropriate  to make its own credit  analysis  and  decision  to enter into this
Assignment and Assumption and to purchase the Assigned  Interest on the basis of
which it has made such analysis and decision  independently and without reliance
on the  Administrative  Agent or any  other  Lender,  and (v) if it is a Foreign
Lender5, attached to the Assignment and Assumption is any documentation required
to be  delivered  by it  pursuant  to the terms of the  Credit  Agreement,  duly
completed  and  executed  by the  Assignee;  and (b)  agrees  that  (i) it will,
independently and without reliance on the Administrative  Agent, the Assignor or
any other Lender,  and based on such documents and  information as it shall deem
appropriate at the time,  continue to make its own credit decisions in taking or
not  taking  action  under  the  Loan  Documents,  and (ii) it will  perform  in
accordance  with their  terms all of the  obligations  which by the terms of the
Loan Documents are required to be performed by it as a Lender.

     2. Payments.  From and after the Effective Date, the  Administrative  Agent
shall make all payments in respect of the Assigned Interest  (including payments
of  principal,  interest,  fees and other  amounts) to the  Assignor for amounts
which have accrued to but excluding  the Effective  Date and to the Assignee for
amounts which have accrued from and after the Effective Date.

______________
4 Describe Credit Agreement at option of Administrative Agent.
5 The  concept of  "Foreign  Lender"  should be  conformed to the section in the
Credit Agreement governng withholding taxes and gross-up.



                                  EXHIBIT A-5






     3. General  Provisions.  This  Assignment and  Assumption  shall be binding
upon,  and inure to the  benefit  of, the  parties  hereto and their  respective
successors  and assigns.  This  Assignment and Assumption may be executed in any
number of counterparts, which together shall constitute one instrument. Delivery
of an executed counterpart of a signature page of this Assignment and Assumption
by telecopy shall be effective as delivery of a manually executed counterpart of
this Assignment and Assumption. This Assignment and Assumption shall be governed
by, and construed in accordance with, the law of the State of Texas.



                                  EXHIBIT A-6





                                    EXHIBIT B

                                     FORM OF

                          NOTICE OF COMMITMENT INCREASE

                                     [Date]



JPMorgan Chase Bank,
[                  ]
Attention:  __________________

Ladies and Gentlemen:

     The undersigned,  Pioneer Natural Resources Company ("PNRC"), refers to the
5-Year Revolving Credit Agreement dated as of  _____________,  2003 (as amended,
supplemented  or otherwise  modified from time to time, the "Credit  Agreement",
with terms  defined in the Credit  Agreement and not  otherwise  defined  herein
being used herein as therein  defined)  among PNRC,  as  borrower,  and JPMorgan
Chase Bank, as Administrative  Agent, and the Lenders party thereto. PNRC hereby
notifies you, pursuant to Section 2.02 of the Credit Agreement, that PNRC hereby
requests that the aggregate amount of the Commitments under the Credit Agreement
be increased  and the CI Lenders agree to provide  Commitments  under the Credit
Agreement,  and in that connection sets forth below the information  relating to
such proposed  Commitment  Increase as required by Section 2.02(b) of the Credit
Agreement:

     (a) the effective date of such increase of aggregate amount of the Lenders'
Commitments is _______________;

     (b)  the  amount  of  the  requested   increase  of  the   Commitments   is
$__________________;

     (c) the CI Lenders that have agreed with PNRC to provide  their  respective
Commitments, are _____________________________ [INSERT NAMES OF THE CI LENDERS];
and

     (d) set forth on Annex I attached  hereto is the  amount of the  respective
Commitments  of  all  Reducing  Percentage  Lenders  and  all CI  Lenders  as of
effective date of such Commitment Increase.

     Delivery of an executed  counterpart of this Notice of Commitment  Increase
by telecopier shall be effective as delivery of an original executed counterpart
of this Notice of Commitment Increase.



                                  EXHIBIT B-1





                                             Very truly yours,


                                             PIONEER NATURAL RESOURCES COMPANY



                                             By:
                                                   ----------------------------
                                             Name:
                                                   ----------------------------
                                             Title:
                                                   ----------------------------
Approved and Consented to by:

JPMORGAN CHASE BANK,
administrative agent



By:
      ------------------------------------------
Name:
      ------------------------------------------
Title:
      ------------------------------------------


                                  EXHIBIT B-2






                                     ANNEX I

                                       TO

                          NOTICE OF COMMITMENT INCREASE

                             (as of _________, 2003)





           Lender                        Amount of         Percentage of Total
                                         Commitment            Commitments
- ---------------------------------     ----------------     -------------------

                                                     
JPMorgan Chase Bank









                          Total:      [700,000,000.00]         100.0000000%





                                  EXHIBIT B-3





                                    EXHIBIT C

                                     FORM OF

                          OPINION OF BORROWER'S COUNSEL








                                   EXHIBIT C






                                    EXHIBIT D

                                     FORM OF

                               SUBSIDIARY GUARANTY

     This  SUBSIDIARY  GUARANTY is dated as of [ ], 2003 made by [ ], a [ ] (the
"Subsidiary  Guarantor"),  in favor of JPMorgan  Chase Bank,  as  administrative
agent (in such  capacity,  together with its  successors in such  capacity,  the
"Administrative  Agent"),  for the banks and other financial  institutions  (the
"Lenders") from time to time parties to the 5-Year  Revolving  Credit  Agreement
dated as of December 16, 2003 (as amended,  supplemented  or otherwise  modified
from time to time,  the "Credit  Agreement"),  among Pioneer  Natural  Resources
Company (the  "Borrower"),  the  Administrative  Agent,  the Issuing Banks,  the
Lenders party  thereto,  Wachovia  Bank,  National  Association,  as Syndication
Agent,  Bank of America,  N.A., Bank One, N.A., Fleet National Bank, Wells Fargo
Bank,  National  Association,   as  Co-Documentation  Agents,  and  J.P.  Morgan
Securities Inc. and Wachovia  Capital  Markets,  LLC, as Co-Arrangers  and Joint
Bookrunners.

                                 R E C I T A L S

     A._______The  Borrower has requested that the Lenders provide certain loans
to and extensions of credit on behalf of the Borrower.

     B._______The  Lenders  have  agreed to make such  loans and  extensions  of
credit subject to the terms and conditions of the Credit Agreement.

     C._______It  is a condition  precedent to the  obligation of the Lenders to
make their  respective  extensions  of credit to the  Borrower  under the Credit
Agreement (or an ongoing  covenant of the Borrower  under the Credit  Agreement)
that the Subsidiary  Guarantor shall have executed and delivered this Subsidiary
Guaranty to the Administrative Agent for the benefit of the Lenders.

     D. NOW,  THEREFORE,  in  consideration of the premises herein and to induce
the Administrative  Agent and the Lenders to enter into the Credit Agreement and
to induce  the  Lenders  to make their  respective  extensions  of credit to the
Borrower   thereunder,   the  Subsidiary   Guarantor   hereby  agrees  with  the
Administrative Agent, for the benefit of the Lenders, as follows:

     Section 1. Definitions.  Unless otherwise defined herein,  terms defined in
the Credit  Agreement  and used  herein have the  meanings  given to them in the
Credit Agreement. The following terms have the following meanings:

     "Liabilities" means the collective reference to the payment and performance
when due of all indebtedness,  liabilities,  obligations and undertakings of the
Borrower  (including,  without  limitation,  all  Indebtedness) of every kind or
description arising out of or outstanding under, advanced or issued pursuant to,
or evidenced by, the Loan Documents,  including,  without limitation, the unpaid
principal  of and  interest  on the  Loans  and the LC  Exposure  and all  other
obligations  and  liabilities of the Borrower  (including,  without  limitation,
interest  accruing at the then applicable rate provided in the Credit  Agreement


                                  EXHIBIT D-1






after the maturity of the Loans and LC Exposure and interest  accruing after the
filing of any petition in bankruptcy,  or the  commencement  of any  insolvency,
reorganization  or like proceeding,  relating to the Borrower,  whether or not a
claim for post-filing or  post-petition  interest is allowed in such proceeding)
to the Guaranteed Creditors, whether direct or indirect, absolute or contingent,
due or to become due,  now  existing or  hereafter  incurred,  arising out of or
outstanding  under,  advanced  or issued  pursuant,  or  evidenced  by, the Loan
Documents,  whether on account of principal,  interest,  premium,  reimbursement
obligations,   payments  in  respect  of  an  early   termination   date,  fees,
indemnities,  costs, expenses or otherwise (including,  without limitation,  all
costs,  fees and  disbursements of counsel to the Guaranteed  Creditors that are
required  to be  paid  by the  Borrower  pursuant  to  the  terms  of  any  Loan
Documents).

     "Guaranteed Creditors" means the collective reference to the Administrative
Agent, the Issuing Banks and the Lenders.

     Section 2. Rules of  Interpretation.  Section  1.03 and Section 1.04 of the
Credit Agreement are hereby  incorporated herein by reference and shall apply to
this Agreement, mutatis mutandis.

     Section 3. Guaranty of Payments.  The Subsidiary Guarantor  unconditionally
and irrevocably  guarantees to the Guaranteed  Creditors the punctual payment of
the Liabilities, when the same are due and payable, whether on demand, at stated
maturity,  by  acceleration or otherwise,  and whether for principal,  interest,
fees,  expenses,   indemnification  or  otherwise;  provided  that  the  maximum
liability of the Subsidiary  Guarantor  shall not exceed the amount which can be
guaranteed by the Subsidiary  Guarantor under applicable  federal and state laws
relating  to the  insolvency  of  debtors;  provided,  further,  however,  it is
understood that the obligations of the Borrower to the Guaranteed  Creditors may
at any  time  and from  time to time  exceed  the  liability  of the  Subsidiary
Guarantor   hereunder  without  impairing  this  Subsidiary   Guaranty  and  the
Subsidiary  Guarantor and the Guaranteed Creditors agree, as between themselves,
that regardless of the manner of application of payments made by the Borrower to
the Guaranteed Creditors,  all such payments shall be deemed to be applied first
to the portion of the  obligations of the Borrower to the  Guaranteed  Creditors
which are not guaranteed  hereunder and last to the portion of such  obligations
which are  guaranteed  hereunder.  This  Subsidiary  Guaranty  is a guaranty  of
payment  and not of  collection  only.  The  Guaranteed  Creditors  shall not be
required to exhaust any right or remedy or take any action  against the Borrower
or any other person or entity or any collateral. The Subsidiary Guarantor agrees
that, as between the  Subsidiary  Guarantor and the  Guaranteed  Creditors,  the
Liabilities  may be  declared  to be due and  payable  for the  purposes of this
Subsidiary Guaranty  notwithstanding  any stay,  injunction or other prohibition
which may prevent,  delay or vitiate any declaration as regards the Borrower and
that in the event of a declaration  or attempted  declaration,  the  Liabilities
shall  immediately  become due and payable by the  Subsidiary  Guarantor for the
purposes  of this  Subsidiary  Guaranty.  No payment  made by any Obligor or any
other  Person or received or  collected  by the  Guaranteed  Creditors  from any
Obligor or any other Person by virtue of any action or proceeding or any set-off
or appropriation or application at any time or from time to time in reduction of
or in payment of the Liabilities shall be deemed to modify,  reduce,  release or
otherwise  affect the  liability of any  Subsidiary  Guarantor  hereunder  which
shall,  notwithstanding  any such  payment  (other than any payment made by such


                                  EXHIBIT D-2






Subsidiary  Guarantor in respect of the  Liabilities or any payment  received or
collected from such Subsidiary Guarantor in respect of the Liabilities),  remain
liable  for the  Liabilities  up to the  maximum  liability  of such  Subsidiary
Guarantor hereunder until the Liabilities are paid in full in cash, no Letter of
Credit shall be outstanding and all of the Commitments are terminated.

     Section 4. Guaranty Absolute and  Unconditional.  The Subsidiary  Guarantor
guarantees  that the  Liabilities  shall be paid strictly in accordance with the
terms of the Loan  Documents.  The liability of the Subsidiary  Guarantor  under
this Subsidiary Guaranty is absolute and unconditional  irrespective of: (a) any
change in the time,  manner or place of payment of, or in any other term of, all
or any of the Loan Documents or Liabilities, or any other amendment or waiver of
or any  consent  to  departure  from any of the  terms of any Loan  Document  or
Liabilities, including any increase or decrease in the rate of interest thereon;
(b) any release or  amendment or waiver of, or consent to  departure  from,  any
other guaranty or support document,  or any exchange,  release for all or any of
the Loan Documents or Liabilities;  (c) any present or future law, regulation or
order of any jurisdiction (whether of right or in fact) or of any agency thereof
purporting to reduce,  amend,  restructure  or otherwise  affect any term of any
Loan Document or  Liabilities;  (d) without being limited by the foregoing,  any
lack of validity or enforceability of any Loan Document or Liabilities;  (e) the
insolvency,  bankruptcy arrangement,  reorganization,  adjustment,  composition,
liquidation,  disability,  dissolution  or lack of power of the  Borrower  , any
Subsidiary  Guarantor  or any other Person at any time liable for the payment of
all or part of the  Liabilities,  including  any  discharge  of,  or bar or stay
against  collecting,  any Liability (or any part of them or interest therein) in
or as a result of such proceeding; (f) any sale, lease or transfer of any or all
of the assets of the Borrower or any other Subsidiary Guarantor,  or any changes
in the shareholders of the Borrower or the Subsidiary  Guarantor;  any change in
the corporate existence (including its constitution, laws, rules, regulations or
power), structure or ownership of any Obligor; (g) the absence of any attempt to
collect  the  Obligations  or any part of them from any  Obligor;  (h) any sale,
exchange,  waiver,  surrender or release of any  guarantee or right of offset at
any time held by the  Guaranteed  Creditors for the payment of the  Liabilities;
(i) the addition,  from time to time, of any guarantors,  makers or endorsers of
the Liabilities,  or of any additional security or collateral for the payment of
the Liabilities;  and (j) any other setoff, defense or counterclaim  whatsoever,
or any other  circumstance  or act whatsoever with respect to the Loan Documents
or the transactions  contemplated thereby which might constitute or be construed
to  constitute a legal or equitable  defense  available to, or discharge of, the
Borrower or a Subsidiary Guarantor under the Credit Agreement or this Subsidiary
Guaranty,  in bankruptcy or in any other instance (in any case, except a defense
of payment or performance, whether based on contract, tort or any other theory).
When making any demand hereunder or otherwise pursuing their rights and remedies
hereunder against any Subsidiary  Guarantor,  the Guaranteed  Creditors may, but
shall be under no obligation  to, join or make a similar  demand on or otherwise
pursue  or  exhaust  such  rights  and  remedies  as they may have  against  the
Borrower,  any other  Subsidiary  Guarantor  or any other  Person or against any
guarantee for the Liabilities or any right of offset with respect  thereto,  and
any failure by the Guaranteed  Creditors to make any such demand, to pursue such
other rights or remedies or to collect any payments from the Borrower, any other
Subsidiary  Guarantor or any other Person or to realize upon any such  guarantee
or to exercise  any such right of offset,  or any release of the  Borrower,  any
other Subsidiary Guarantor or any other Person or any such guarantee or right of
offset,  shall  not  relieve  any  Subsidiary  Guarantor  of any  obligation  or
liability  hereunder,  and shall not impair or affect  the rights and  remedies,
whether  express,  implied or  available  as a matter of law, of the  Guaranteed
Creditors  against any Subsidiary  Guarantor.  For the purposes  hereof "demand"
shall include the commencement and continuance of any legal proceedings.


                                  EXHIBIT D-3







     Section 5. Guaranty  Irrevocable.  This Subsidiary Guaranty is a continuing
guaranty of all Liabilities  now or hereafter  existing under the Loan Documents
and  shall  remain  in  full  force  and  effect  until  payment  in full of all
Liabilities and other amounts  payable under this Subsidiary  Guaranty and until
the Loan Documents are no longer in effect.

     Section 6.  Reinstatement.  This  Subsidiary  Guaranty shall continue to be
effective, or be reinstated,  as the case may be, if at any time any payment, or
any part thereof,  of any of the  Liabilities  is rescinded or must otherwise be
returned by the Guaranteed Creditors on the insolvency, bankruptcy, dissolution,
liquidation or reorganization of the Borrower or any Subsidiary  Guarantor,  all
as though the payment had not been made.

     Section  7.  No  Subrogation.  Notwithstanding  any  payment  made  by  any
Subsidiary  Guarantor  hereunder or any set-off or  application  of funds of any
Subsidiary Guarantor by the Guaranteed Creditors,  no Subsidiary Guarantor shall
be entitled to be  subrogated to any of the rights of the  Guaranteed  Creditors
against  the  Borrower  or any  other  Subsidiary  Guarantor  or any  collateral
security or guarantee or right of offset held by any Guaranteed Creditor for the
payment  of the  Liabilities,  nor shall  any  Subsidiary  Guarantor  seek or be
entitled to seek any  indemnity,  exoneration,  participation,  contribution  or
reimbursement from the Borrower or any other Subsidiary  Guarantor in respect of
payments made by such Subsidiary Guarantor hereunder, until all amounts owing to
the  Guaranteed  Creditors on account of the  Liabilities  are  irrevocably  and
indefeasibly  paid in full in cash, no Letter of Credit shall be outstanding and
all of the  Commitments  are  terminated.  If any  amount  shall  be paid to any
Subsidiary  Guarantor on account of such subrogation rights at any time when all
of the Liabilities shall not have been irrevocably and indefeasibly paid in full
in cash, any Letter of Credit shall be outstanding or any of the Commitments are
in effect,  such amount shall be held by such Subsidiary  Guarantor in trust for
the Guaranteed Creditors,  and shall,  forthwith upon receipt by such Subsidiary
Guarantor, be turned over to the Administrative Agent in the exact form received
by such Subsidiary  Guarantor (duly indorsed by such Subsidiary Guarantor to the
Administrative  Agent,  if  required),  to be applied  against the  Liabilities,
whether matured or unmatured, as determined by the Administrative Agent.

     Section 8. Subordination. Without limiting the Guaranteed Creditors' rights
under  any  other  agreement,  any  liabilities  owed  by  the  Borrower  to the
Subsidiary  Guarantor in  connection  with any  extension of credit or financial
accommodation by the Subsidiary Guarantor to or for the account of the Borrower,
including but not limited to interest accruing at the agreed contract rate after
the commencement of a bankruptcy or similar proceeding,  are hereby subordinated
to the Liabilities  upon the occurrence of an Event of Default,  and, in such an
event such  liabilities  of the  Borrower to the  Subsidiary  Guarantor,  if the
Administrative Agent so requests,  shall be collected,  enforced and received by
the Subsidiary  Guarantor as trustee for the  Guaranteed  Creditors and shall be
paid  over  to the  Administrative  Agent  for  the  benefit  of the  Guaranteed
Creditors on account of the Liabilities  (but only to the extent due and payable
but without  reducing or affecting in any manner the liability of the Subsidiary
Guarantor under the other provisions of this Subsidiary Guaranty.


                                  EXHIBIT D-4






     Section 9. Payments  Generally.  All payments by the  Subsidiary  Guarantor
shall be made in the  manner,  at the place and in the  currency  (the  "Payment
Currency")  required  by the Loan  Documents;  provided,  however,  that (if the
Payment  Currency is other than U.S.  dollars) the Subsidiary  Guarantor may, at
its option (or, if for any reason whatsoever the Subsidiary  Guarantor is unable
to effect payments in the foregoing  manner,  the Subsidiary  Guarantor shall be
obligated to) pay to the  Administrative  Agent at its principal office, for the
benefit of the  Guaranteed  Creditors,  the  equivalent  amount in U.S.  dollars
computed  at the  selling  rate of the  Administrative  Agent or a selling  rate
chosen by the  Administrative  Agent, most recently in effect on or prior to the
date the Liability  becomes due, for cable transfers of the Payment  Currency to
the place where the  Liability is payable.  In any case in which the  Subsidiary
Guarantor makes or is obligated to make payment in U.S. dollars,  the Subsidiary
Guarantor  shall  hold the  Administrative  Agent and the  Guaranteed  Creditors
harmless from any loss incurred by the  Administrative  Agent or the  Guaranteed
Creditors  arising  from any change in the value of U.S.  dollars in relation to
the Payment Currency between the date the Liability becomes due and the date the
Guaranteed  Creditors are actually  able,  following the  conversion of the U.S.
dollars  paid  by  the  Subsidiary  Guarantor  into  the  Payment  Currency  and
remittance  of such  Payment  Currency  to the place  where  such  Liability  is
payable, to apply such Payment Currency to such Liability.

     Section 10. Certain Taxes. The Subsidiary Guarantor further agrees that all
payments to be made hereunder shall be made without setoff or  counterclaim  and
free and clear of, and without  deduction for, any  Indemnified  Taxes and Other
Taxes. If any Indemnified Taxes and Other Taxes are required to be withheld from
any  amounts  payable  to  the  Administrative  Agent  for  the  benefit  of the
Guaranteed  Creditors  hereunder,  the amounts so payable to the  Administrative
Agent for the benefit of the  Guaranteed  Creditors  shall be  increased  to the
extent  necessary to yield to the  Guaranteed  Creditors  (after  payment of all
Indemnified  Taxes and Other  Taxes) the amounts  payable  hereunder in the full
amounts so to be paid.  Whenever any Indemnified  Taxes and Other Taxes are paid
by the Subsidiary Guarantor, as promptly as possible thereafter,  the Subsidiary
Guarantor  shall  send the  Administrative  Agent an  official  receipt  showing
payment thereof,  together with such additional  documentary  evidence as may be
required from time to time by the Administrative Agent.

     Section  11.  Representations  and  Warranties.  The  Subsidiary  Guarantor
represents  and  warrants  that:  (a)  this  Subsidiary  Guaranty  (i) has  been
authorized by all  necessary  corporate  action;  (ii) except as to matters that
could not reasonably be expected to result in a Material  Adverse  Effect,  does
not violate any agreement,  instrument,  law,  regulation or order applicable to
the  Subsidiary  Guarantor;  (iii) does not require the consent or approval  of,
registration or filing with, or any other action by, any Governmental Authority;
and (iv) is the legal, valid and binding obligation of the Subsidiary  Guarantor
enforceable  against the  Subsidiary  Guarantor  in  accordance  with its terms,
subject to applicable bankruptcy,  insolvency,  reorganization,  moratorium,  or
other  laws  affecting  creditors'  rights  generally  and  subject  to  general
principles of equity regardless of whether  considered in a proceeding in equity
or at law; and (b) in executing and delivering  this  Subsidiary  Guaranty,  the
Subsidiary Guarantor has (i) without reliance on the Administrative Agent or the
Guaranteed  Creditors or any information  received from the Administrative Agent
or the  Guaranteed  Creditors and based upon such  documents and  information it
deems  appropriate,  made  an  independent  investigation  of  the  transactions


                                  EXHIBIT D-5





contemplated  hereby  and  the  Borrower,   the  Borrower's  business,   assets,
operations,   prospects  and   condition,   financial  or  otherwise,   and  any
circumstances  which  may bear  upon  such  transactions,  the  Borrower  or the
obligations and risks undertaken  herein with respect to the  Liabilities;  (ii)
adequate  means to obtain from the  Borrower on a continuing  basis  information
concerning  the  Borrower;  (iii)  has  full  and  complete  access  to the Loan
Documents  and  any  other  documents  executed  in  connection  with  the  Loan
Documents;  and (iv) not  relied and will not rely upon any  representations  or
warranties of the Administrative  Agent or the Guaranteed Creditors not embodied
herein or any acts heretofore or hereafter taken by the Administrative  Agent or
the  Guaranteed  Creditors  (including  but not  limited  to any  review  by the
Administrative  Agent  or  the  Guaranteed  Creditors  of  the  affairs  of  the
Borrower).

     Section 12. Remedies  Generally.  The remedies  provided in this Subsidiary
Guaranty are cumulative and not exclusive of any remedies provided by law.

     Section 13.  Formalities.  The  Subsidiary  Guarantor  waives  presentment,
notice of dishonor, protest, notice of acceptance of this Subsidiary Guaranty or
incurrence of any Liability and any other  formality  with respect to any of the
Liabilities or this Subsidiary Guaranty.

     Section 14.  Amendments and Waivers to Guaranty.  No amendment or waiver of
any provision of this Subsidiary  Guaranty,  nor consent to any departure by the
Subsidiary Guarantor  therefrom,  shall be effective unless it is in writing and
signed by each of the Guaranteed Creditors, and then the waiver or consent shall
be  effective  only in the specific  instance  and for the specific  purpose for
which given. No failure on the part of the Guaranteed Creditors to exercise, and
no delay in exercising,  any right under this Subsidiary  Guaranty shall operate
as a waiver or preclude any other or further exercise thereof or the exercise of
any other right.  Each Subsidiary  Guarantor hereby waives any and all notice of
the creation, renewal, extension or accrual of any of the Liabilities and notice
of or proof  of  reliance  by the  Guaranteed  Creditors  upon  this  Subsidiary
Guaranty or acceptance of this Subsidiary Guaranty; the Liabilities,  and any of
them, shall conclusively be deemed to have been created, contracted or incurred,
or  renewed,  extended,  amended or waived,  in  reliance  upon this  Subsidiary
Guaranty and no notice of creation of the Liabilities or any extension of credit
already or hereafter  contracted by or extended to the Borrower need be given to
any Subsidiary  Guarantor;  and all dealings between the Borrower and any of the
Subsidiary  Guarantors,  on the one hand, and the Guaranteed  Creditors,  on the
other  hand,  likewise  shall  be  conclusively  presumed  to have  been  had or
consummated in reliance upon this Subsidiary Guaranty. Each Subsidiary Guarantor
waives diligence, presentment, protest, demand for payment and notice of default
or nonpayment to or upon the Borrower or any of the Subsidiary  Guarantors  with
respect to the Liabilities.

     Section  15.  Expenses.   The  Subsidiary  Guarantor  shall  reimburse  the
Administrative  Agent for the benefit of the Guaranteed  Creditors on demand for
all reasonable  out-of-pocket  expenses (including without limitation reasonable
fees,  charges and  disbursements  of any counsel for the Guaranteed  Creditors)
incurred by the Guaranteed  Creditors in connection with the enforcement of this
Subsidiary  Guaranty.  Attorneys' fees reimbursed by the Subsidiary Guarantor in
connection  with this  Subsidiary  Guaranty  shall be for a single  law firm per
country (unless conflicts (including conflicts between the Administrative Agent,
the  Co-Arrangers  and  the  other  Lenders  as  determined  in  the  reasonable
discretion  of the Required  Lenders)  otherwise  prohibit the  engagement  of a
single law firm) plus a single local  counsel in each  jurisdiction  where local
counsel is reasonably required.


                                  EXHIBIT D-6






     Section 16. Assignment.  This Subsidiary  Guaranty shall be binding on, and
shall inure to the benefit of the Subsidiary Guarantor, the Administrative Agent
and the  Guaranteed  Creditors  and their  respective  successors  and  assigns;
provided that the Subsidiary  Guarantor may not assign or transfer its rights or
obligations under this Subsidiary  Guaranty.  Without limiting the generality of
the  foregoing:  (a) the  obligations  of the  Subsidiary  Guarantor  under this
Subsidiary Guaranty shall continue in full force and effect and shall be binding
on any  successor  partnership  and on previous  partners  and their  respective
estates if the Subsidiary  Guarantor is a partnership,  regardless of any change
in the  partnership  as a result of death  retirement or otherwise;  and (b) the
Guaranteed  Creditors may assign,  sell  participations in or otherwise transfer
their rights under the Loan  Documents to another person or entity to the extent
expressly  permitted  by  Section  9.04 of the Credit  Agreement,  and the other
person or entity  shall then become  vested  with all the rights  granted to the
Guaranteed Creditors in this Subsidiary Guaranty or otherwise.

     Section 17. Captions. The headings and captions in this Subsidiary Guaranty
are for convenience only and shall not affect the interpretation or construction
of this Subsidiary Guaranty.

     Section 18. Governing Law, Etc. THIS SUBSIDIARY  GUARANTY SHALL BE GOVERNED
BY THE LAW OF THE STATE OF  TEXAS.  THE  SUBSIDIARY  GUARANTOR  CONSENTS  TO THE
NONEXCLUSIVE  JURISDICTION  AND VENUE OF THE STATE OR FEDERAL  COURTS LOCATED IN
THE STATE OF TEXAS.  SERVICE OF PROCESS BY THE BANK IN CONNECTION  WITH ANY SUCH
DISPUTE SHALL BE BINDING ON THE  SUBSIDIARY  GUARANTOR IF SENT TO THE SUBSIDIARY
GUARANTOR  BY  REGISTERED  MAIL AT THE ADDRESS  SPECIFIED  BELOW OR AS OTHERWISE
SPECIFIED  BY THE  SUBSIDIARY  GUARANTOR  FROM  TIME  TO  TIME.  THE  SUBSIDIARY
GUARANTOR  WAIVES ANY RIGHT THE  SUBSIDIARY  GUARANTOR MAY HAVE TO JURY TRIAL IN
ANY ACTION RELATED TO THIS SUBSIDIARY GUARANTY OR THE TRANSACTIONS  CONTEMPLATED
HEREBY AND FURTHER  WAIVES ANY RIGHT TO INTERPOSE  ANY  COUNTERCLAIM  RELATED TO
THIS SUBSIDIARY  GUARANTY OR THE  TRANSACTIONS  CONTEMPLATED  HEREBY IN ANY SUCH
ACTION. TO THE EXTENT THAT THE SUBSIDIARY GUARANTOR HAS OR HEREAFTER MAY ACQUIRE
ANY IMMUNITY FROM  JURISDICTION OF ANY COURT OR FROM ANY LEGAL PROCESS  (WHETHER
FROM  SERVICE OR NOTICE,  ATTACHMENT  PRIOR TO  JUDGMENT,  ATTACHMENT  IN AID OF
EXECUTION  OF A JUDGMENT,  EXECUTION OR  OTHERWISE),  THE  SUBSIDIARY  GUARANTOR
HEREBY IRREVOCABLY WAIVES SUCH IMMUNITY IN RESPECT OF ITS OBLIGATIONS UNDER THIS
SUBSIDIARY GUARANTY.


                                  EXHIBIT D-7






     Section 19.  Integration;  Effectiveness.  This written Subsidiary Guaranty
embodies  the entire  agreement  and  understanding  between the Lenders and the
Subsidiary  Guarantor and  supersedes all other  agreements  and  understandings
between  such  parties  relating  to the subject  matter  hereof.  This  written
Subsidiary  Guaranty  represents the final agreement between the parties and may
not be  contradicted by evidence of prior,  contemporaneous,  or subsequent oral
agreements of the parties.  There are no unwritten oral  agreements  between the
parties.


                                  EXHIBIT D-8





     IN WITNESS  WHEREOF,  the Subsidiary  Guarantor has caused this  Subsidiary
Guaranty to be duly executed and delivered by its duly authorized  officer as of
the date first above written.

                                             PIONEER NATURAL RESOURCES USA INC.


                                             By:
                                                ------------------------------
                                             Name:
                                             Title:


                                             Address:



                                  EXHIBIT D-9







                                    EXHIBIT E

                                     FORM OF

                                 PROMISSORY NOTE

$[       ]                                                  [        ], 200[  ]

     FOR  VALUE  RECEIVED,   Pioneer  Natural  Resources   Company,  a  Delaware
corporation,  (the  "Borrower")  hereby promises to pay to the order of [ ] (the
"Lender"),  at the principal office of JPMorgan Chase Bank (the  "Administrative
Agent"),  at [ ], the principal sum of [ ] Dollars ($[ ]) (or such lesser amount
as shall equal the aggregate  unpaid  principal  amount of the Loans made by the
Lender to the Borrower under the Credit Agreement,  as hereinafter  defined), in
lawful money of the United States of America and in immediately available funds,
on the dates and in the principal amounts provided in the Credit Agreement,  and
to pay  interest  on the  unpaid  principal  amount of each such  Loan,  at such
office,  in like money and funds, for the period  commencing on the date of such
Loan until  such Loan  shall be paid in full,  at the rates per annum and on the
dates provided in the Credit Agreement.

     The date, amount, Type, interest rate, Interest Period and maturity of each
Loan made by the Lender to the Borrower, and each payment made on account of the
principal  thereof,  shall be recorded by the Lender on its books and,  prior to
any  transfer of this Note,  may be endorsed  by the Lender on  schedules  to be
attached hereto or any continuation thereof or on any separate record maintained
by the Lender.  Failure to make any such notation or to attach a schedule  shall
not affect any Lender's or the  Borrower's  rights or  obligations in respect of
such Loans or affect the validity of such transfer by any Lender of this Note.

     This Note is one of the Notes referred to in the Credit  Agreement dated as
of December [ ], 2003 among the  Borrower,  the  Administrative  Agent,  and the
other agents and lenders signatory thereto (including the Lender), and evidences
Loans made by the Lender  thereunder  (such Credit  Agreement as the same may be
amended,  supplemented  or restated from time to time, the "Credit  Agreement").
Capitalized  terms used in this Note have the  respective  meanings  assigned to
them in the Credit Agreement.

     This Note is issued pursuant to the Credit Agreement and is entitled to the
benefits provided for in the Credit Agreement and the other Loan Documents.  The
Credit Agreement provides for the acceleration of the maturity of this Note upon
the occurrence of certain  events,  for  prepayments of Loans upon the terms and
conditions specified therein and other provisions relevant to this Note.

     THIS NOTE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE  WITH, THE LAWS
OF THE STATE OF TEXAS.


                                  EXHIBIT E-1








     IN WITNESS  WHEREOF,  the  Borrower  has caused this  Agreement  to be duly
executed as of the day and year first above written.

                                            PIONEER NATURAL RESOURCES COMPANY


                                            By:
                                                  -----------------------------
                                            Name:
                                                  -----------------------------
                                            Title:
                                                  -----------------------------



                                  EXHIBIT E-2