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                                                                  Exhibit 10.246

                   FIRST AMENDMENT TO OFFICE LEASE AGREEMENT

     This First Amendment to Office Lease Agreement (this "First Amendment") is
made and entered into by and between KBS PHOENIX IV, L.L.C., a Delaware limited
liability company (the "Landlord") and READY MIX, INC., a Nevada corporation
("Tenant"), effective as of August 31, 2003 (the "Effective Date").


                              W I T N E S S E T H:

     WHEREAS, Landlord and Tenant heretofore executed and entered into that
certain Office Lease Agreement dated May 26, 2000 (the "Original Lease"),
pursuant to which Tenant leased certain premises containing 2,260 Rentable
Square Feet (the "Original Premises") in the building commonly known as 26th
Place, located 2601 East Thomas Road, Phoenix, Arizona 85016 (the "Building");
and

     WHEREAS, Landlord and Tenant desire to amend the terms of the Lease to
relocate Tenant, extend the Lease Term, and to modify certain terms and
provisions of the Lease, all as more particularly set forth below;

     NOW, THEREFORE, for and in consideration of the premises contained herein,
and other good and valuable consideration paid by each of Landlord and Tenant to
the other, the receipt and sufficiency of which are hereby acknowledged,
Landlord and Tenant agree that the Lease is hereby ratified and amended as
follows:

1.   Defined Terms. All capitalized terms used herein shall have the same
     meaning as defined in the Lease, unless otherwise defined in this First
     Amendment.

2.   Extension of Lease Term. Landlord and Tenant acknowledge and agree that the
     Lease Term is hereby scheduled to expire on August 31, 2003. Landlord and
     Tenant hereby acknowledge and agree the Lease Term shall be extended for
     the period commencing September 1, 2003 and continuing through and expiring
     on the day preceding the thirty-sixth (36th) month anniversary of the
     Relocation Date (as defined below) (the "Extension Term"), upon and subject
     to all of the existing terms of the Lease except as otherwise hereafter set
     forth.

3.   Relocation Space. Effective as of the date upon which there is Substantial
     Completion of the Relocation Space Tenant Improvements in the Relocation
     Space (the "Relocation Date"), and subject to the conditions of Paragraph 5
     below, the Premises shall be relocated from the Original Premises to that
     certain space containing approximately 3,189 Rentable Square Feet located
     in Suite 120 of the Building (the "Relocation Space"), as more particularly
     described on Exhibit A attached hereto, and, from and after the Relocation
     Date, all references to the Premises shall mean the Relocation Space.
     Landlord and Tenant acknowledge and agree that Landlord and Tenant will
     execute an amendment that serves as confirmation of Relocation Date when
     the Relocation Date (and the expiration date of the Extension Term) is
     determined.


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4.  Released Space.  Effective as of the Relocation Date, with respect to the
    Released Space only, Tenant covenants and agrees with Landlord that as a
    condition precedent to Tenant's occupancy of the Relocation Space, Tenant
    hereby surrenders the approximate 2,260 Rentable Square Feet located in
    Suite 235 of the Building (collectively, the "Released Space"), which is
    more particularly described on Exhibit B attached hereto, subject to the
    following:

       (a)  With respect to the Released Space only, as of the Relocation Date,
            Tenant agrees to surrender the Released Space in substantially the
            same condition as existed upon commencement of the Lease, reasonable
            wear and tear excepted, and with all personal property of Tenant
            removed therefrom. Tenant hereby releases, as of the Relocation
            Date, all of its right, title and interest in, and in respect of,
            the Released Space. Tenant covenants, agrees and represents that
            Tenant shall have no further right to use, occupy or have possession
            of the Released Space or any portion thereof after the Relocation
            Date.

       (b)  With respect to the Released Space only, Tenant covenants and agrees
            that it has full right, power and authority to terminate and
            surrender the Released Space in the manner aforesaid.

       (c)  Subject to Paragraph 5(a) above and Paragraph 5(e) below with
            respect to the Released Space only, Landlord agrees (i) to forever
            release and discharge Tenant from all obligations, covenants and
            agreements of Tenant arising under or in connection with the
            Released Space after the Relocation Date and (ii) not to sue Tenant
            for obligations covenants and agreements of Tenant arising under or
            in connection with the Released Space after the Relocation Date.

       (d)  With respect to the Released Space only, Tenant agrees (i) to
            forever release and discharge Landlord from all obligations,
            covenants and agreements of Landlord arising under or in connection
            with the Released Space and (ii) not to sue Landlord for
            obligations, covenants and agreements of Landlord arising under or
            in connection with the Released Space.

       (e)  Notwithstanding anything to the contrary herein contained, with
            respect to the Released Space only, the parties acknowledge and
            agree that each shall continue to be fully liable to the other to
            the extent set forth in the Lease for any claim for personal injury
            or property damage arising prior to the Relocation Date. Tenant
            shall also be responsible for any Operating Costs reimbursable that
            may be due, when the actual Operating Costs for the calendar year
            2004 for the Building are determined in 2005.

       (f)  With respect to the Released Space only, Tenant covenants and agrees
            with Landlord that Tenant shall make or cause to be made any further
            assurances of the termination and the surrender of the Released
            Space as Landlord may reasonably require from time to time.

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5.   Confirmation of Premises. Effective on and as of the Relocation Date, the
     "Premises" shall consist of the Relocation Space, which is Suite 120,
     containing 3,189 Rentable Square Feet.

6.   Minimum Monthly Rent. From and after September 1, 2003, the Minimum Monthly
     Rent for the Relocation Space shall be as follows:

     (a)  For the period commencing September 1, 2003 and continuing through the
          day immediately preceding the Relocation Date, the Monthly Minimum
          Rent shall be equal to $3,393.77 per month, plus applicable rental
          sales tax;

     (b)  For the period commencing on the Relocation Date and continuing
          through the day immediately preceding the twelfth (12th) month
          anniversary of the Relocation Date, the Minimum Monthly Rent shall be
          $3,986.25 per month (being equal to $15.00 per Rentable Square Foot
          per annum), plus applicable rental sales tax;

     (c)  For the period commencing on the twelfth (12th) month anniversary of
          the Relocation Date and continuing through the day immediately
          preceding the twenty-fourth (24th) month anniversary of the Relocation
          Date, the Minimum Monthly Rent shall be $4,119.13 per month (being
          equal to $15.50 per Rentable Square Foot per annum), plus applicable
          rental sales tax; and

     (d)  For the period commencing on the twenty-fourth (24th) month
          anniversary of the Relocation Date and continuing through the last day
          of the Extension Term, the Minimum Monthly Rent shall be $4,252.00 per
          month (being equal to $16.00 per Rentable Square Foot per annum), plus
          applicable rental sales tax.

7.   Relocation Space Tenant Improvements. The Relocation Space is hereby leased
     to Tenant in its "AS-IS", "WHERE-IS" and "WITH ALL FAULTS" condition and
     Landlord shall have no obligation to refurbish or otherwise improve the
     Relocation Space for the Extension Term; provided that, subject to the
     terms of the Work Letter attached hereto as Exhibit C. Landlord shall
     perform the certain improvements to the Relocation Space in accordance
     with, and subject to the terms of, said Exhibit C attached hereto and made
     a part hereof for all purposes.

8.   Tenant's Pro Rata Share. As of the Relocation Date, Landlord and Tenant
     acknowledge and agree that Tenant's Pro Rata Share, as specified in Article
     1.1(h) of the Lease, shall be amended to be 10.107% (3,189 rsf/31,553 rsf).

9.   Security Deposit. Concurrently with the execution of the First Amendment,
     Landlord and Tenant hereby agree that Tenant shall pay an additional
     Security Deposit of $858.23 (the "Extension Term Security Deposit"). Upon
     payment of the Extension Term Security Deposit, the total Security Deposit
     (including the Extension


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    Term Security Deposit and the Security Deposit paid upon execution of the
    Lease) held by Landlord, from and after the Relocation Date, is equal to
    $4,252.00.

10. Parking. Effective on and as of the Relocation Date, Landlord and Tenant
    acknowledge and agree that Article 6.1 of the Lease shall be amended so
    that Tenant shall have a license to use (12) parking spaces of which there
    will be (i) three (3) covered, reserved in Automobile Parking Areas
    designated by Landlord from time to time at the additional cost to Tenant
    of $25.00 per parking space per month, plus applicable rental sales tax
    during the Extension Term (from and after the Relocation Date) and (ii)
    nine (9) uncovered, unreserved parking spaces at no additional cost to
    Tenant during the Extension Term (from and after the Relocation Date).

11. Brokers. Tenant warrants that it has had no dealings with any broker or
    agent other than CB Richard Ellis, Inc. (the "Broker") in connection with
    the negotiation or execution of this First Amendment, and Tenant agrees to
    indemnify Landlord and hold Landlord harmless from and against any and all
    costs, expenses, or liability for commissions or other compensations or
    charges claimed by any broker or agent, other than the Broker, with respect
    to this First Amendment.

12. Miscellaneous. With the exception of those terms and conditions
    specifically modified and amended herein, the herein referenced Lease shall
    remain in full force and effect in accordance with all its terms and
    conditions. In the event of any conflict between the terms and provisions
    of this First Amendment and the terms and provisions of the Lease, the
    terms and provisions of this First Amendment shall supersede and control.

13. Counterparts/Facsimiles. This First Amendment may be executed in any number
    of counterparts, each of which shall be deemed an original, and all of such
    counterparts shall constitute one agreement. To facilitate execution of
    this First Amendment, the parties may execute and exchange facsimile
    counterparts of the signature pages and facsimile counterparts shall serve
    as originals.




                           [SIGNATURE PAGE TO FOLLOW]








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          SIGNATURE PAGE TO FIRST AMENDMENT TO OFFICE LEASE AGREEMENT
                                 BY AND BETWEEN
                    KBS PHOENIX IV, L.L.C., AS LANDLORD, AND
                           READY MIX, INC., AS TENANT

     IN WITNESS WHEREOF, Landlord and Tenant, acting herein by duly authorized
individuals, have caused these presents to be executed on the respective dates
set forth below, to be effective for all purposes, however, as of the Effective
Date set forth herein.

                                     LANDLORD:

                                     KBS PHOENIX IV, L.L.C.,
                                     A DELAWARE LIMITED LIABILITY COMPANY

                                     BY:  KOLL BREN SCHREIBER REALTY ADVISORS,
                                          INC., A DELAWARE CORPORATION, AS AGENT




                                          BY: /s/ David L. Kray
                                             -------------------------------
                                              DAVID L. KRAY,
                                              SENIOR VICE PRESIDENT

                                          DATE: 9/17     , 2003
                                                ---------

                                     TENANT:

                                     READY MIX, INC.,
                                     A NEVADA CORPORATION



                                     BY: /s/ Robert A. DeRuiter
                                        -------------------------
                                     NAME: Robert A. DeRuiter
                                          -----------------------
                                     TITLE: General Manager
                                          -----------------------

                                     DATE: 9-9    , 2003
                                          --------



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