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                                                                  EXHIBIT 10.122

                            Master Security Agreement

   This Master Security Agreement provides a set of terms and conditions that
   the parties hereto intend to be applicable to various loan transactions
   secured by personal property. Each such loan and security agreement shall be
   evidenced by a schedule of indebtedness and collateral ("Schedule") executed
   by Secured Party and Debtor that explicitly incorporates the provisions of
   this Master Security Agreement and that sets forth specific terms of that
   particular loan and security contract. Where the provisions of a Schedule
   conflict with the terms hereof, the provisions of the Schedule shall prevail.
   Each Schedule shall constitute a complete and separate loan and security
   agreement, independent of all other Schedules, and without any requirement of
   being accompanied by an originally executed copy of this Master Security
   Agreement. The term "Security Agreement" when used herein shall refer to an
   individual Schedule.

   One originally executed copy of the Schedule shall be denominated "Originally
   Executed Copy No. 1 of 1 originally executed copies" and such copy shall be
   retained by Secured Party. If more than one copy of the Schedule is executed
   by Secured Party and Debtor, all such other copies shall be numbered
   consecutively with numbers greater than 1. Only transfer of possession by
   Secured Party of Originally Executed Copy No. 1 shall be effective for
   purposes of perfecting an interest in such Schedule by possession.

   1.  Grant of Security Interest; Description of Collateral.

   Debtor grants to Secured Party a security interest in the property described
   in the Schedules now or hereafter executed by or pursuant to the authority of
   the Debtor and accepted by Secured Party in writing, along with all present
   and future attachments and accessories thereto and replacements and proceeds
   thereof, including amounts payable under any insurance policy, all
   hereinafter referred to collectively as "Collateral." Each Schedule shall be
   serially numbered. Unless and only to the extent otherwise expressly provided
   in a Schedule, no Schedule shall replace any previous Schedule but shall be
   supplementary to all previous Schedules.

   2.  What Obligations the Collateral Secures.

   Each item of Collateral shall secure not only the specific amount which
   Debtor promises to pay in each Schedule, but also all other present and
   future indebtedness or obligations of Debtor to Secured Party of every kind
   and nature whatsoever.

   3.  Promise to Pay; Terms and Place of Payment.

   Debtor promises to pay Secured Party the amounts set forth on each Schedule
   at the rate and upon such terms as provided therein.

   4.  Use and Location of Collateral.

   Debtor warrants and agrees that the Collateral is to be used primarily for:
   [x] business or commercial purposes (other than agricultural),
   [_] agricultural purposes (see definition on the final page), or
   [_] both agricultural and business or commercial purposes.

   Location: 4411 South 40th Street     Phoenix     Maricopa    AZ     85040
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             Address                    City        County      State  Zip Code

   Debtor and Secured Party agree that regardless of the manner of affixation,
   the Collateral shall remain personal property and not become part of the real
   estate. Debtor agrees to keep the Collateral at the location set forth above,
   and will notify Secured Party promptly in writing of any change in the
   location of the Collateral within such State, but will not remove the
   collateral from such State without the prior written consent of Secured Party
   (except that in the State of Pennsylvania, the Collateral will not be moved
   from the above location without such prior written consent.

   5.  Late Charges and Other Fees.

   Any payment not made when due shall, at the option of Secured Party, bear
   late charges thereon calculated at the rate of 1 1/2% per month, but in no
   event greater than the highest rate permitted by relevant law. Debtor shall
   be responsible for and pay to Secured Party a returned check fee, not to
   exceed the maximum permitted by law, which fee will be equal to the sum of
   (i) the actual bank charges incurred by Secured Party plus (ii) all other
   actual costs and expenses incurred by Secured Party. The returned check fee
   is payable upon demand as indebtedness secured by the Collateral under this
   Security Agreement.

   6.  Debtor's Warranties and Representations.
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Debtor warrants and represents:

(a) that Debtor is justly indebted to Secured Party for the full amount of the
    indebtedness set forth on each Schedule;

(b) that except for the security interest granted hereby, the Collateral is free
    from and will be kept free from all liens, claims, security interests and
    encumbrances;

(c) that no financing statement covering the Collateral or any proceeds thereof
    is on file in favor of anyone other than Secured Party, but if such other
    financing statement is on file, it will be terminated or subordinated;

(d) that all information supplied and statements made by Debtor in any
    financial, credit or accounting statement or application for credit prior
    to, contemporaneously with or subsequent to the execution of this Security
    Agreement with respect to this transaction are and shall be true, correct,
    valid and genuine; and

(e) that Debtor has full authority to enter into this agreement and in so doing
    it is not violating its charter or by -laws, any law or regulation or
    agreement with third parties, and it has taken all such action as may be
    necessary or appropriate to make this Security Agreement binding upon it.

7.  Debtor's Agreements.

Debtor agrees:

(a) to defend at Debtor's own cost any action, proceeding, or claim affecting
    the Collateral;

(b) to pay reasonable attorneys' fees (at least 15% of the unpaid balance if not
    prohibited by law) and other expenses incurred by Secured Party in enforcing
    its rights against Debtor under this Security Agreement;

(c) to pay promptly all taxes, assessments, license fees and other public or
    private charges when levied or assessed against the Collateral or this
    Security Agreement, and this obligation shall survive the termination of
    this Security Agreement;

(d) that if a certificate of title be required or permitted by law, Debtor shall
    obtain such certificate with respect to the Collateral, showing the security
    interest of Secured Party thereon and in any event do everything necessary
    or expedient to preserve or perfect the security interest of Secured Party;

(e) that Debtor will not misuse, fail to keep in good repair, secrete or without
    the prior written consent of Secured Party, sell, rent, lend, encumber or
    transfer any of the Collateral notwithstanding Secured Party's right to
    proceeds;

(f) that Secured Party may enter upon Debtor's premises or wherever the
    Collateral may be located at any reasonable time to inspect the Collateral
    and Debtor's books and records pertaining to the Collateral, and Debtor
    shall assist Secured Party in making such inspection; and

(g) that the security interest granted by Debtor to Secured Party shall continue
    effective irrespective of any retaking or redelivery of any Collateral and
    irrespective of the payment of the amount described in any Schedule so long
    as there are any obligations of any kind, including obligations under
    guaranties or assignments, owed by Debtor to Secured Party, provided,
    however, upon any assignment of this Security Agreement the Assignee shall
    thereafter be deemed for the purpose of this Paragraph the Secured Party
    under this Security Agreement.

8.  Insurance and Risk of Loss.

All risk of loss, damage to or destruction of the Collateral shall at all times
be on Debtor. Debtor will procure forthwith and maintain at Debtor's expense
insurance against all risks of loss or physical damage to the Collateral for the
full insurable value thereof for the life of this Security Agreement plus breach
of warranty insurance and such other insurance thereon in amounts and against
such risks as Secured Party may specify, and shall promptly deliver each policy
to Secured Party with a standard long-form mortgagee endorsement attached
thereto showing loss payable to Secured Party; and providing Secured Party with
not less than 30 days written notice of cancellation; each such policy shall be
in form, terms and amount and with insurance carriers satisfactory to Secured
Party; Secured Party's acceptance of policies in lesser amounts or risks shall
not be a waiver of Debtor's foregoing obligations. As to Secured Party's
interest in such policy, no act or omission of Debtor or any of its officers,
agents, employees or representatives shall affect the obligations of the insurer
to pay the full amount of any loss.

Debtor hereby assigns to Secured Party any monies which may become payable under
any such policy of insurance and irrevocably constitutes and appoints Secured
Party as Debtor's attorney in fact (a) to hold each original insurance policy,
(b) to make, settle and adjust claims under each policy of insurance, (c) to
make claims for any monies which may become payable under such and other
insurance on the Collateral including returned or unearned premiums, and (d) to
endorse Debtor's name on any check, draft or other instrument received in
payment of claims or returned or unearned premiums under each policy and to
apply the funds to the payment of the indebtedness owing to Secured Party;
provided, however, Secured Party is under no obligation to do any of the
foregoing.
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Should Debtor fail to furnish such insurance policy to Secured Party, or to
maintain such policy in full force, or to pay any premium in whole or in part
relating thereto, then Secured Party, without waiving or releasing any default
or obligation by Debtor, may (but shall be under no obligation to) obtain and
maintain insurance and pay the premium therefor on behalf of Debtor and charge
the premium to Debtor's indebtedness under this Security Agreement. The full
amount of any such premium paid by Secured Party shall be payable by Debtor upon
demand, and failure to pay same shall constitute an event of default under this
Security Agreement.

9.  Events of Default; Acceleration.

A very important element of this Security Agreement is that Debtor make all its
payments promptly as agreed upon. It is essential that the Collateral remain in
good condition and adequate security for the indebtedness. The following are
events of default under this Security Agreement which will allow Secured Party
to take such action under this Paragraph and under Paragraph 10 as it deems
necessary:

(a) any of Debtor's obligations to Secured Party under any agreement with
    Secured Party is not paid promptly when due;

(b) Debtor breaches any warranty or provision hereof, or of any note or of any
    other instrument or agreement delivered by Debtor to Secured Party in
    connection with this or any other transaction;

(c) Debtor dies, becomes insolvent or ceases to do business as a going concern;

(d) it is determined that Debtor has given Secured Party materially misleading
    information regarding its financial condition;

(e) any of the Collateral is lost or destroyed;

(f) a complaint in bankruptcy or for arrangement or reorganization or for relief
    under any insolvency law is filed by or against Debtor or Debtor admits its
    inability to pay its debts as they mature;

(g) property of Debtor is attached or a receiver is appointed for Debtor;

(h) whenever Secured Party in good faith believes the prospect of payment or
    performance is impaired or in good faith believes the Collateral is
    insecure;

(i) any guarantor, surety or endorser for Debtor dies or defaults in any
    obligation or liability to Secured Party or any guaranty obtained in
    connection with this transaction is terminated or breached.

If Debtor shall be in default hereunder, the indebtedness described in each
Schedule and all other indebtedness then owing by Debtor to Secured Party under
this or any other present or future agreement (collectively, the "Indebtedness")
shall, if Secured Party shall so elect, become immediately due and payable.
After acceleration:

(a) the unpaid principal balance of the indebtedness described in any Schedule
    in which interest has been precomputed shall bear interest at the rate of
    18% per annum (or, if less, the maximum rate permitted by law) until paid in
    full; and

(b) the unpaid principal balance of the indebtedness described in any Schedule
    in which interest has not been precomputed shall bear interest at the same
    rate as before acceleration until paid in full.

In no event shall the Debtor upon demand by Secured Party for payment of the
Indebtedness, by acceleration of the maturity thereof or otherwise, be obligated
to pay any interest in excess of the amount permitted by law. Any acceleration
of the indebtedness, if elected by Secured Party, shall be subject to all
applicable laws, including laws relating to rebates and refunds of unearned
charges.

10. Secured Party's Remedies After Default; Consent to Enter Premises.

Upon Debtor's default and at any time thereafter, Secured Party shall have all
the rights and remedies of a secured party under the Uniform Commercial Code and
any other applicable laws, including the right to any deficiency remaining after
disposition of the Collateral for which Debtor hereby agrees to remain fully
liable. Debtor agrees that Secured Party, by itself or its agent, may without
notice to any person and without judicial process of any kind, enter into any
premises or upon any land owned, leased or otherwise under the real or apparent
control of Debtor or any agent of Debtor where the Collateral may be or where
Secured Party believes the Collateral may be, and disassemble, render unusable
and/or repossess all or any item of the Collateral, disconnecting and separating
all Collateral from any other property and using all force necessary. Debtor
expressly waives all further rights to possession of the Collateral after
default and all claims for injuries suffered through or loss caused by such
entering and/or repossession. Secured Party may require Debtor to assemble the
Collateral and return it to Secured Party at a place to be designated by Secured
Party which is reasonably convenient to both parties.
<PAGE>

Secured Party may sell or lease the Collateral at a time and location of its
choosing provided that the Secured Party acts in good faith and in a
commercially reasonable manner. Secured Party will give Debtor reasonable notice
of the time and place or any public sale of the Collateral or of the time after
which any private sale or any other intended disposition of the Collateral is to
be made. Unless otherwise provided by law, the requirement of reasonable notice
shall be met if such notice is mailed, postage prepaid, to the address of Debtor
shown herein at least ten days before the time of the sale or disposition.
Expenses of retaking, holding, preparing for sale, selling and the like shall
include reasonable attorneys' fees (at least 15% of the outstanding principal
balance if not prohibited by law) and other legal expenses. Debtor understands
that Secured Party's rights are cumulative and not alternative.

11. Waiver of Defaults; Agreement Inclusive.

Secured Party may in its sole discretion waive a default, or cure, at Debtor's
expense, a default. Any such waiver in a particular instance or of a particular
default shall not be a waiver of other defaults or the same kind of default at
another time. No modification or change in this Security Agreement or any
related note, instrument or agreement shall bind Secured Party unless in writing
signed by Secured Party. No oral agreement shall be binding.

12. Financing Statements; Certain Expenses.

If permitted by law Debtor authorizes Secured Party to file a financing
statement with respect to the Collateral signed only by Secured Party, and to
file a carbon, photograph or other reproduction of this Security Agreement or of
a financing statement. At the request of Secured Party, Debtor will execute any
financing statements, agreements or documents, in form satisfactory to Secured
Party which Secured Party may deem necessary or advisable to establish and
maintain a perfected security interest in the Collateral and will pay the cost
of filing or recording the same in all public offices deemed necessary or
advisable by Secured Party. Debtor also agrees to pay all costs and expenses
incurred by Secured Party in conducting UCC, tax or other lien searches against
the Debtor or the Collateral and such other fees as may be agreed.

13. Waiver of Defenses Acknowledgment.

If Secured Party assigns this Security Agreement to a third party ("Assignee"),
then after such assignment:

(a) Debtor will make all payments directly to such Assignee at such place as
    Assignee may from time to time designate in writing;

(b) Debtor agrees that it will settle all claims, defenses, setoffs and
    counterclaims it may have against Secured Party directly with Secured Party
    and will not set up any such claim, defense, setoff or counterclaim against
    Assignee, Secured Party hereby agreeing to remain responsible therefor;

(c) Secured Party shall not be Assignee's agent for any purpose and shall have
    no authority to change or modify this Security Agreement or any related
    document or instrument; and

(d) Assignee shall have all of the rights and remedies of Secured Party
    hereunder but none of Secured Party's obligations.

14. Miscellaneous.

Debtor waives all exemptions. Secured Party may correct patent errors herein and
fill in such blanks as serial numbers, date of first payment and the like. Any
provisions hereof contrary to, prohibited by or invalid under applicable laws or
regulations shall be inapplicable and deemed omitted herefrom, but shall not
invalidate the remaining provisions hereof.

Debtor and Secured Party each hereby waive any right to a trial by jury in any
action or proceeding with respect to, in connection with, or arising out of this
Security Agreement, or any note or document delivered pursuant to this Security
Agreement. Except as otherwise provided herein or by applicable law, the Debtor
shall have no right to prepay the indebtedness described in any Schedule. Debtor
acknowledges receipt of a true copy and waives acceptance hereof.

If Debtor is a corporation, this Security Agreement is executed pursuant to
authority of its Board of Directors. Except where the context otherwise
requires, "Debtor" and "Secured Party" include the heirs, executors or
administrators, successors or assigns of those parties; nothing herein shall
authorize Debtor to assign this Security Agreement or its rights in and to the
Collateral. If more than one Debtor executes this Security Agreement, their
obligations under this Security Agreement shall be joint and several.

If at any time this transaction would be usurious under applicable law, then
regardless of any provision contained in this Security Agreement or in any other
agreement made in connection with this transaction, it is agreed that:

(a)  the total of all consideration which constitutes interest under applicable
     law that is contracted for, charged or received upon this Security
     Agreement or any such other agreement shall under no circumstances exceed
     the maximum rate of interest authorized by applicable law and any excess
     shall be credited to the Debtor; and

(b)  If Secured Party elects to accelerate the maturity of, or if Secured Party
     permits Debtor to prepay the indebtedness described in Paragraph 3, any
     amounts which because of such action would constitute interest may never
     include more than the maximum rate of interest authorized by applicable law
     and any excess interest, if any, provided for in this Security Agreement or
     otherwise, shall be credited to Debtor automatically as of the date of
     acceleration or prepayment.
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15. Special Provisions.

See Special Provisions Instructions.







Dated: 4-5-2000
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Debtor.

Meadow Valley Contractors, Inc.
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Name of individual, corporation or partnership

By /s/ Kenneth D. Nelson                      Title Vice President
   -------------------------------------------      ---------------
If corporation, have signed by President, Vice President or Treasurer, and give
official title. If owner or partner, state which.





4411 South 40th Street
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Address

Phoenix                                    AZ         85040
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CitY                                     State       Zip Code


Secured Party:


The CIT Group/Eguipment Financing, Inc.
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Name of individual, corporation or partnership


By /s/ Kathy Taylor                           Title Agent
   -------------------------------------------      ---------------
   If corporation, give official title. If owner or partner, state which.

P.O. Box 27248
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Address

Tempe                                   AZ        85285-7248
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City                                  State       Zip Code