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                            FIRST AMENDMENT TO CREDIT AGREEMENT

         THIS FIRST AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is entered
into as of May 11, 1999, by and between WATKINS CONTRACTING, INC., a Nevada
corporation ("Borrower"), and WELLS FARGO BANK, NATIONAL ASSOCIATION ("Bank").

                                    RECITALS

         WHEREAS, Borrower is currently indebted to Bank pursuant to the terms
and conditions of that certain Credit Agreement between Borrower and Bank dated
as of November 10, 1998, as amended from time to time ("Credit Agreement").

         WHEREAS, Bank and Borrower have agreed to certain changes in the terms
and conditions set forth in the Credit Agreement and have agreed to amend the
Credit Agreement to reflect said changes.

         NOW, THEREFORE, for valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties hereto agree that the Credit
Agreement shall be amended as follows:

         1. Section 1.1(a) is hereby amended by deleting "Exhibit A attached
hereto" as the Line of Credit Note exhibit reference, and by substituting
"Exhibit A to the First Amendment to this agreement" for said reference.

         2. Section 4.3 is hereby deleted in its entirety, and the following
substituted therefor:


                  "(a) not later than 20 days after and as of the end of each
         month, a borrowing base certificate, an aged listing of accounts
         receivable with a breakdown of retention on each job, and an aging of
         accounts payable with a breakout of sub-contracts payable and retention
         to subcontractors and suppliers;"

         3. Section 4.9 is hereby deleted in its entirety, and the following
substituted therefor:

                  "SECTION 4.9. FINANCIAL CONDITION. Maintain Borrower's
         financial condition as follows using generally accepted accounting
         principles consistently applied and used consistently with prior
         practices (except to the extent modified by the definitions herein),
         with compliance determined


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         commencing with Borrower's financial statements for the period ending
         April 30, 1999:

                  (a) Current Ratio not at any time less than 1.00 to 1.0, with
         "Current Ratio" defined as total current assets divided by total
         current liabilities.

                  (b) Tangible Net Worth not at any time less than
         $1,050,000.00, with "Tangible Net Worth" defined as the aggregate of
         total stockholders' equity plus subordinated debt less any intangible
         assets.

                  (c) Total Liabilities divided by Tangible Net Worth not at any
         time greater than 5.0 to 1.0 from the date of this agreement up through
         May 31, 1999; and 4.0 to 1.0 at all times thereafter, with "Total
         Liabilities" defined as the aggregate of current liabilities and
         non-current liabilities less subordinated debt, and with "Tangible Net
         Worth" as defined above.

                  (d) Net income after taxes not less than $1.00 on an monthly
         basis beginning with the month ending March 30, 1999, determined as of
         each month end."

         4. Section 5.2 is hereby deleted in its entirety, and the following
substituted therefor:

                  "SECTION 5.2. OTHER INDEBTEDNESS. Create, incur, assume or
         permit to exist any indebtedness or liabilities resulting from
         borrowings, loans or advances, whether secured or unsecured, matured or
         unmatured, liquidated or unliquidated, joint or several, except (a) the
         liabilities of Borrower to Bank, and (b) any other liabilities of
         Borrower existing as of, and disclosed to Bank prior to, the date
         hereof."

         5. Section 5.5 is hereby deleted in its entirety, and the following
substituted therefor:

                  "SECTION 5.5. LOANS, ADVANCES, INVESTMENTS. Make any loans or
         advances to or investments in any person or entity or paid out any
         management fees, except any of



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         the foregoing existing as of, and disclosed to Bank prior to, the date
         hereof."

         6. The following is hereby added to the Credit Agreement as Section
5.7:

                  "SECTION 5.7. DIVIDENDS, DISTRIBUTIONS. Declare or pay any
         dividend or distribution either in cash, stock or any other property on
         Borrower's stock now or hereafter outstanding, nor redeem, retire,
         repurchase or otherwise acquire any shares of any class of Borrower's
         stock now or hereafter outstanding."

         7. Except as specifically provided herein, all terms and conditions of
the Credit Agreement remain in full force and effect, without waiver or
modification. All terms defined in the Credit Agreement shall have the same
meaning when used in this Amendment. This Amendment and the Credit Agreement
shall be read together, as one document.

         8. Borrower hereby remakes all representations and warranties contained
in the Credit Agreement and reaffirms all covenants set forth therein. Borrower
further certifies that as of the date of this Amendment there exists no Event of
Default as defined in the Credit Agreement, nor any condition, act or event
which with the giving of notice or the passage of time or both would constitute
any such Event of Default.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the day and year first written above.

                                                      WELLS FARGO BANK,
WATKINS CONTRACTING, INC.                             NATIONAL ASSOCIATION

By: /s/ Greg S. Watkins                               By: /s/ David Bruen
    --------------------                                  ---------------
    Greg S. Watkins                                       David Bruen
     President                                            Vice President


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