Centennial's Amended and Restated Master Shelf Agreement


    

      LETTER
        AMENDMENT NO. 1

      TO

      AMENDED
        AND RESTATED MASTER SHELF AGREEMENT

       

            
        May 17, 2006

      


      


      
        	
                Prudential
                  Investment Management, Inc.

              	
                General
                  Electric Capital Assurance Company

              
	
                The
                  Prudential Insurance Company of America

              	
                General
                  Electric Life and Annuity Assurance Company

              
	
                Pruco
                  Life Insurance Company

              	
                First
                  Colony Life Insurance Company

              
	
                Pruco
                  Life Insurance Company of New Jersey

              	 
	
                Hartford
                  Life Insurance Company

              	 
	
                Security
                  Life of Denver Insurance Company

              	 
	
                ING
                  USA Annuity and Life Insurance Company

              	 
	
                Reliastar
                  Life Insurance Company

              	 
	
                ING
                  Life Insurance and Annuity Company

              	 
	
                United
                  of Omaha Life Insurance Company

              	 
	
                Mutual
                  of Omaha Insurance Company

              	 
	
                The
                  Prudential Life Insurance Company, Ltd.

              	 
	
                Prudential
                  Retirement Insurance and Annuity Company

              	 
	
                Security
                  Benefit Life Insurance Company, Inc.

              	 
	
                Farmers
                  New World Life Insurance Company

              	 
	
                Zurich
                  American Insurance Company

              	 
	
                Physicians
                  Mutual Insurance Company

              	 
	
                American
                  Skandia Life Assurance Corporation

              	 
	
                RGA
                  Reinsurance Company

              	 
	
                Union
                  Security Insurance Company

              	 
	
                American
                  Bankers Insurance Company of Florida, Inc.

              	 
	
                c/o
                  Prudential Capital Group

              	 
	
                2200
                  Ross Avenue, Suite 4200E

              	 
	
                Dallas,
                  Texas 75201

              	 


      

      


      Ladies
        and Gentlemen:

      


      We
        refer
        to the Amended and Restated Master Shelf Agreement dated as of December 27,
        1999
        (effective as of April 29, 2005) (the "Agreement")
        among
        the undersigned, Centennial Energy Holdings, Inc. (the "Company"),
        Prudential Investment Management, Inc. ("Prudential"),
        The
        Prudential Insurance Company of America ("PICA"),
        Pruco
        Life Insurance Company ("Pruco"),
        Pruco
        Life Insurance Company of New Jersey ("Pruco
        NJ"),
        Hartford Life Insurance Company ("Hartford"),
        Security Life of Denver Insurance Company ("Security
        Life"),
        ING
        USA Annuity and Life Insurance Company ("ING
        USA"),
        Reliastar Life Insurance Company ("Reliastar"),
        ING
        Life Insurance and Annuity Company ("ING
        Life"),
        United of Omaha Life Insurance Company ("United"),
        Mutual of Omaha Insurance Company ("Mutual"),
        The
        Prudential Life Insurance Company, Ltd. ("Prudential
        Life"),
        Prudential Retirement Insurance and Annuity Company ("PRIAC"),
        Security Benefit Life Insurance Company, Inc. ("Security
        Benefit"),
        Farmers New World Life Insurance Company ("Farmers"),
        Zurich American Insurance Company ("Zurich"),
        Physicians Mutual Insurance Company ("Physicians"),
        American Skandia Life Assurance Corporation ("American"),
        RGA
        Reinsurance Company ("RGA"),
        Union
        Security Insurance Company ("Union"),
        American Bankers Insurance Company of Florida, Inc. ("ABIC"),
        General Electric Capital Assurance Company ("GECAC"),
        General Electric Life and Annuity Assurance Company ("GELAAC"),
        First
        Colony Life Insurance Company ("First
        Colony";
        and
        together with PICA, Pruco, Pruco NJ, Hartford, Security Life, ING USA,
        Reliastar, ING Life, United, Mutual, Prudential Life, PRIAC, Security Benefit,
        Farmers, Zurich, Physicians, American, RGA, Union, ABIC, GECAC and GELAAC,
        the
        "Holders").
        Unless otherwise defined herein, the terms defined in the Agreement shall
        be
        used herein as therein defined.

      


      The
        Company desires to increase the amount of the Notes available to be issued
        under
        the Agreement to an aggregate principal amount of $550,000,000 (creating
        an
        Available Facility Amount of $115,500,000 as of the date hereof), to extend
        the
        Issuance Period and to make certain other amendments to the
        Agreement.

      


      Therefore,
        Prudential, the Holders and the Company, in consideration of the mutual promises
        and agreements set forth herein and in the Agreement, agree as
        follows:

      


      (a) Section 1.2.
        Section
        1.2 of the Agreement is amended in full to read as follows:

      


      "1.2. Authorization
        of Issue of Notes. 

      


      (a) The
        Company will authorize the issue of its senior promissory notes (the
        'Notes')
        in the
        aggregate principal amount of $550,000,000 to be dated the date of issue
        thereof; to mature, in the case of each Note so issued, no more than 12 years
        after the date of original issuance thereof; to have an average life, in
        the
        case of each note so issued, of no more than 10 years after the date of original
        issuance thereof; to bear interest on the unpaid balance thereof from the
        date
        thereof at the rate per annum, and to have such other particular terms, as
        shall
        be set forth, in the case of each Note so issued, in the Confirmation of
        Acceptance with respect to such Note delivered pursuant to Section 2.6; and
        to
        be substantially in the form of Exhibit 1
        attached
        hereto. The term 'Notes'
        as used
        herein shall include each Note delivered pursuant to any provision of this
        Agreement and each Note delivered in substitution or exchange for any such
        Note
        pursuant to any such provision. Notes which have (i) the same final
        maturity, (ii) the same installment payment dates, (iii) the same
        installment payment amounts (as a percentage of the original principal amount
        of
        each Note), (iv) the same interest rate, (v) the same interest payment periods,
        and (vi) the same original date of issuance are herein called a 'Series'
        of
        Notes. Certain
        capitalized terms used in this Agreement are defined in Schedule B; references
        to a 'Schedule' or an 'Exhibit' are, unless otherwise specified, to a Schedule
        or an Exhibit attached to this Agreement.

      


      (b) The
        Company will authorize the issue and sale of $100,000,000 aggregate principal
        amount of its 5.92% Senior Notes, Series N, due 2013 (the 'Series
        N Notes',
        such
        term to include any such notes issued in substitution therefor pursuant to
        Section 13). The Series N Notes shall be substantially in the form set out
        in
        Exhibit 1-A. The Series N Notes will be considered Accepted Notes for purposes
        of this Agreement, including the provisions of Section 4. Subject to the terms
        and conditions of this Agreement, the Company will issue and sell to each
        Purchaser and each Purchaser will purchase from the Company, at the Closing
        for
        the Series N Notes on May 17, 2006, Notes in the principal amount specified
        opposite such Purchaser's name in the Purchaser Schedule for the Series N
        Notes
        at the purchase price of 100% of the principal amount thereof. The Purchasers'
        obligations hereunder are several and not joint obligations and no Purchaser
        shall have any liability to any Person for the performance or non-performance
        of
        any obligation by any other Purchaser hereunder. At the Closing for the Series
        N
        Notes, the Company will deliver to each Purchaser the Notes to be purchased
        by
        such Purchaser in the form of a single Note (or such greater number of Notes
        in
        denominations of at least $100,000 as such Purchaser may request) dated May
        17,
        2006 and registered in such Purchaser's name (or in the name of its nominee),
        against delivery by such Purchaser to the Company or its order of immediately
        available funds in the amount of the purchase price therefor by wire transfer
        of
        immediately available funds for the account of the Company to account number
        163095535494 at U.S. Bank North Dakota, Fargo, Bismarck, ND, ABA number
        091300023 for wire transfers, and any other relevant wire transfer information.
        If at the Closing for the Series N Notes the Company shall fail to tender
        such
        Notes to any Purchaser as provided herein, or any of the conditions specified
        in
        Section 4 shall not have been fulfilled to such Purchaser's satisfaction,
        such Purchaser shall, at its election, be relieved of all further obligations
        under this Agreement, without thereby waiving any rights such Purchaser may
        have
        by reason of such failure or such nonfulfillment."

      


      (b) Section 2.1.
        Section
        2.1 of the Agreement is amended in full to read as follows:

      


      "2.1. Facility;
        Limitation on Facility.

      


      (a) Facility.
        Prudential is willing to consider, in its sole discretion and within limits
        which may be authorized for purchase by Prudential Affiliates from time to
        time,
        the purchase of $550,000,000 of the total amount of authorized Notes pursuant
        to
        this Agreement. The willingness of Prudential to consider such purchase of
        Notes
        is herein called the 'Facility.'
        At any
        time, subject to the additional limitations in Section 2.1(b), the aggregate
        principal amount of Notes stated in Section 1.2, minus
        the
        aggregate principal amount of Notes purchased and sold pursuant to this
        Agreement prior to such time, minus
        the
        aggregate principal amount of Accepted Notes which have not yet been purchased
        and sold hereunder prior to such time, plus
        the
        aggregate principal amount of Notes purchased and sold pursuant to this
        Agreement and thereafter retired prior to such time (to the extent that the
        Company shall have agreed with Prudential to reinstate the Facility with
        respect
        to such amount) is herein called the 'Available
        Facility Amount'
        at such
        time. NOTWITHSTANDING
        THE WILLINGNESS OF PRUDENTIAL TO CONSIDER PURCHASES OF NOTES, THIS AGREEMENT
        IS
        ENTERED INTO ON THE EXPRESS UNDERSTANDING THAT NEITHER PRUDENTIAL NOR ANY
        PRUDENTIAL AFFILIATE SHALL BE OBLIGATED TO MAKE OR ACCEPT OFFERS TO PURCHASE
        NOTES, OR TO QUOTE RATES, SPREADS OR OTHER TERMS WITH RESPECT TO SPECIFIC
        PURCHASES OF NOTES, AND THE FACILITY SHALL IN NO WAY BE CONSTRUED AS A
        COMMITMENT BY PRUDENTIAL OR ANY PRUDENTIAL AFFILIATE.

      


      (b) Limitation
        on Facility.
        Notwithstanding anything in Section 2.1(a), the Company may not request the
        issuance of Notes, and neither Prudential nor any Prudential Affiliate shall
        be
        required to purchase Notes, pursuant to the Facility if, after the issuance
        of
        such Notes, the aggregate amount of Centennial Exposure would exceed
        $350,000,000."

      


      (c) Section 2.2.
        Section
        2.2 of the Agreement is amended in full to read as follows:

      


      "2.2. Issuance
        Period.

      


      Notes
        may
        be issued and sold pursuant to this Agreement until the earlier of (i) May
        8, 2009 (or if such date is not a Business Day, the Business Day next preceding
        such date) and (ii) the thirtieth day after Prudential shall have given to
        the
        Company, or the Company shall have given to Prudential, a notice stating
        that it
        elects to terminate the issuance and sale of Notes pursuant to this Agreement
        (or if such thirtieth day is not a Business Day, the Business Day next preceding
        such thirtieth day). The period during which Notes may be issued and sold
        pursuant to this Agreement is herein called the 'Issuance
        Period'."

       

      
        (d) Section 5.16.
          Section
          5.16 of the Agreement is amended in full to read as follows:

        


        "5.16. Status
          under Certain Statutes.

        


        Neither
          the Company nor any Subsidiary or Affiliate is subject to regulation under
          the
          Investment Company Act of 1940, as amended. The Company is not subject
          to
          regulation under the Interstate Commerce Act, as amended, the Federal Power
          Act,
          as amended, any state public utilities code or statute, or any other Federal
          or
          state statute or regulation limiting its ability to incur
          indebtedness."

        


        (e) Schedule
          B. Defined Terms. The
          definitions of "Other Company Notes" contained in Schedule B of the Agreement
          is
          amended in full to read as follows:

        


        "'Other
          Company Notes' means
          (i)
          the 7.10% Senior Notes due October 30, 2009 of the Company, the 7.09% Senior
          Notes due March 29, 2011 of the Company, the 3.80% Senior Notes due June
          27,
          2008 of the Company, (ii) any other promissory notes of the Company issued
          pursuant to agreements, indentures or other instruments (other than this
          Agreement) and (iii) any other promissory notes of any Subsidiary of the
          Company
          (other than Williston Basin). As of May 8, 2006, $13,500,000 of Other Company
          Notes were part of the Centennial Exposure."

        


        (f) Cover
          Page. The
          Cover
          Page attached to the Agreement is replaced in its entirety by Exhibit
          A
          attached
          to this Letter Amendment No. 1 to Amended and Restated Master Shelf Agreement
          (this "Letter
          Amendment").

        


        (g) Schedule
          5.4.
          Schedule
          5.4 attached to the Agreement is replaced in its entirety by the Schedule
          5.4
          attached hereto as Exhibit
          B.
          The
          Company, the holders of the Notes and the Purchasers agree that Schedule
          5.4 is
          as of April 30, 2006.

        


        (h) Schedule
          5.8.
          Schedule
          5.8 attached to the Agreement is replaced in its entirety by the Schedule
          5.8
          attached hereto as Exhibit
          C.

        


        (i) Schedule
          5.17.
          Schedule
          5.17 attached to the Agreement is replaced in its entirety by the Schedule
          5.17
          attached hereto as Exhibit
          D.

        


        (j) Exhibit
          1-A.
          The
          Agreement is amended by adding behind Exhibit 1 to the Agreement the Exhibit
          1-A
          attached hereto as Exhibit
          E.

        


        (k) Purchaser
          Schedule.
          The
          Purchaser Schedule for the Series N Notes is attached hereto as Exhibit
          F.

        


        On
          and
          after the effective date of this Letter Amendment, each reference in the
          Agreement to "this Agreement", "hereunder", "hereof", or words of like
          import
          referring to the Agreement, and each reference in the Notes to "the Agreement",
          "thereunder", "thereof", or words of like import referring to the Agreement,
          shall mean the Agreement as amended by this Letter Amendment. The Agreement,
          as
          amended by this Letter Amendment, is and shall continue to be in full force
          and
          effect and is hereby in all respects ratified and confirmed. The execution,
          delivery and effectiveness of this Letter Amendment shall not, except as
          expressly provided herein, operate as a waiver of any right, power or remedy
          under the Agreement nor constitute a waiver of any provision of the Agreement.
          

        


        This
          Letter Amendment may be executed in any number of counterparts and by any
          combination of the parties hereto in separate counterparts, each of which
          counterparts shall be an original and all of which taken together shall
          constitute one and the same letter amendment. 


        If
          you
          agree to the terms and provisions hereof, please evidence your agreement
          by
          executing and returning at least a counterpart of this Letter Amendment
          to
          Centennial Energy Holdings, Inc., 1200 W. Century Ave., Bismarck, ND 58503,
          Attention of Chief Financial Officer. This Letter Amendment shall become
          effective as of the date first above written when and if counterparts of
          this
          Letter Amendment shall have been executed by us and you.

      

      


      Very
        truly yours,

      


      CENTENNIAL
        ENERGY

      HOLDINGS,
        INC.

      


      


      By:
        /s/
        VERNON A. RAILE

      Vernon
        A.
        Raile, Executive Vice President, Treasurer and Chief Financial
        Officer

      


      


      Agreed
        as
        of the date first above written:

      


      PRUDENTIAL
        INVESTMENT

      MANAGEMENT,
        INC.

       

      By:
        /s/
        BRIAN N. THOMAS

      Vice
        President

      


      


      THE
        PRUDENTIAL INSURANCE

      COMPANY
        OF AMERICA

       

      By:
        /s/
        BRIAN N. THOMAS

      Vice
        President

      


      


      PRUCO
        LIFE INSURANCE COMPANY

       

      By:
        /s/
        BRIAN N. THOMAS

      Vice
        President

      



      PRUCO
        LIFE INSURANCE COMPANY

      OF
        NEW JERSEY

       

      By:
        /s/
        KELLY A. BRENDEL

      Vice
        President

      


      


      HARTFORD
        LIFE INSURANCE COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

       

      By:
        /s/
        KELLY A. BRENDEL

      Vice
        President

      


      


      SECURITY
        LIFE OF DENVER INSURANCE

      COMPANY,
        as
        successor by merger to Southland

      Life
        Insurance Company

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        By:
          /s/
          KELLY A. BRENDEL

        Vice
          President

      

      



      ING
        USA ANNUITY AND LIFE INSURANCE

      COMPANY,
        f/k/a
        Golden American Life Insurance

      Company

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        By:
          /s/
          KELLY A. BRENDEL

        Vice
          President

      

       

      
 

      RELIASTAR
        LIFE INSURANCE COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        By:
          /s/
          KELLY A. BRENDEL

        Vice
          President

      

      


      


      ING
        LIFE INSURANCE AND ANNUITY

      COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      



      UNITED
        OF OMAHA LIFE INSURANCE

      COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      


      


      MUTUAL
        OF OMAHA INSURANCE COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      


      


      THE
        PRUDENTIAL LIFE INSURANCE

      COMPANY,
        LTD.

      


      By: Prudential
        Investment Management (Japan),

      Inc.,
        as
        Investment Manager

      


      By: Prudential
        Investment Management, Inc.,

      as
        Sub-Adviser

      


      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      


      



      PRUDENTIAL
        RETIREMENT INSURANCE

      AND
        ANNUITY COMPANY

      


      By: Prudential
        Investment Management, Inc.,

      as
        investment manager

      


       

      
        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      


      


      SECURITY
        BENEFIT LIFE INSURANCE

      COMPANY,
        INC.

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


       

      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      


      


      FARMERS
        NEW WORLD LIFE INSURANCE

      COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


       By:
        /s/
        KELLY A. BRENDEL
        
          Vice
            President

        

      

      


      



      ZURICH
        AMERICAN INSURANCE COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      


      


      PHYSICIANS
        MUTUAL INSURANCE

      COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


       By:
        /s/
        KELLY A. BRENDEL
        
          Vice
            President

        

      

       

      


      


      AMERICAN
        SKANDIA LIFE ASSURANCE

      CORPORATION

      


      By: Prudential
        Investment Management, Inc.,

      as
        investment manager

      


       By:
        /s/
        KELLY A. BRENDEL
        
          Vice
            President

        

      

      



      RGA
        REINSURANCE COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

       

      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      


      


      UNION
        SECURITY INSURANCE COMPANY

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


       

      
        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        



      


      AMERICAN
        BANKERS INSURANCE COMPANY

      OF
        FLORIDA, INC.

      


      By: Prudential
        Private Placement Investors,

      L.P.
        (as
        Investment Advisor)

      


      By: Prudential
        Private Placement Investors, Inc.

      (as
        its
        General Partner)

      


      
        


        
          By:
            /s/
            KELLY A. BRENDEL

          Vice
            President

        

      

      



      GENERAL
        ELECTRIC CAPITAL

      ASSURANCE
        COMPANY

      


      


      By:
        ________________________________

      Name:

      Title:

      


      


      GENERAL
        ELECTRIC LIFE AND ANNUITY

      ASSURANCE
        COMPANY

      


      


      By:
        ________________________________

      Name:

      Title:

      


      


      FIRST
        COLONY LIFE INSURANCE COMPANY

      


      


      By:
        ________________________________

      Name:

      Title: