“ Credit Obligations ” means all present and future liabilities, obligations and Indebtedness of the Borrowers, any of their Subsidiaries or any other Obligor owing to the Agent or any Lender (or any Affiliate of a Lender and including any Issuing Bank) under or in connection with this Agreement or any other Credit Document, including obligations in respect of principal, interest, reimbursement obligations under Letters of Credit, fees, Letter of Credit fees, amounts provided for in Sections 3.2.4, 3.4, 3.5 and 12 and other fees, charges, indemnities and expenses from time to time owing hereunder or under any other Credit Document (whether accruing before or after a Bankruptcy Default).

“ Final Maturity Date ” means July 28, 2009, or such later date to which the Final Maturity Date has been extended in accordance with Section 2.6.

“ Foreign Currency ” means such currencies other than United States Dollars as may be approved by the Lenders in their sole discretion.  Each Foreign Currency must be one (a) that is freely transferable and convertible into United States Dollars, and (b) in which deposits are generally available to all Lenders in the London Interbank Market.  The Lenders approve each of the following as a Foreign Currency:  Canadian Dollars, Euros, Sterling, Australian Dollars, Hong Kong Dollars and Singapore Dollars.

“ Foreign Indebtedness ” is defined in Section 9.7.15.

“ Issuing Bank ” means any Lender, as applicable, in each case in its capacity as the issuer of a Letter of Credit.

“ LC Available Credit ” means the lesser of (a) $100,000,000 less the current Letter of Credit Exposure, or (b) the Available Credit.

“ Lender ” means each of the Persons listed as lenders on the signature page hereto, including Wells Fargo in its capacity as a Lender and the Swing Line Lender and each Lender in its capacity as an Issuing Bank, and such other Persons who may from time to time own a Percentage Interest in the Credit Obligations, but the term “Lender” will not include any Credit Participant.

“ Letter of Credit Agreement ” means an Issuing Bank’s standard letter of credit application and documentation modified to such extent, if any, as such Issuing Bank deems necessary.

“ Letter of Credit Exposure ” means, at any date, the sum of (a) the aggregate face amount of all drafts that may then or thereafter be presented by beneficiaries under all Letters of Credit then outstanding, plus (b) the aggregate face amount of all drafts that the Issuing Banks have previously accepted under Letters of Credit but that the Borrowers have not paid to such Issuing Banks.

“ Multicurrency Available Credit ”  means the lesser of (i) the U.S. Dollar Equivalent of $25,000,000 less the aggregate outstanding balance of all Multicurrency LIBOR Loans, or (ii) the Available Credit.

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“ Permitted Acquisition ” means an Acquisition that meets the following conditions:

(a)                                   Such proposed Permitted Acquisition does not cause the aggregate cash purchase price of all Acquisitions in any one calendar year to equal or exceed $100,000,000; provided that the Required Lenders will not unreasonably withhold their consent to additional Acquisitions and the Agent shall receive at least 10 days prior written notice of any proposed Permitted Acquisition for which the cash consideration exceeds $15,000,000;

(b)                                  Such proposed Permitted Acquisition shall only involve assets or businesses comprising a business, or those assets of a business, substantially of the type engaged in by the Borrowers as of the date of this Agreement;

(c)                                   Such proposed Permitted Acquisition shall be consensual and shall have been approved by the Target’s board of directors (and stockholders to the extent required by applicable law);

(d)                                  Prior to the closing of such proposed Permitted Acquisition for which cash consideration exceeds $15,000,000, the Borrowers shall deliver to the Agent, pro forma Consolidated financial statements for the Parent and its Subsidiaries, including the Target, in form satisfactory to the Agent, accompanied by a certificate of a Financial Officer certifying that, after giving effect to such proposed Permitted Acquisition, (i) the Borrowers will be in compliance with the financial covenants set forth in Section 9.4 through 9.6 on a pro forma basis, (ii) the ratio of Total Funded Debt divided by Adjusted EBITDA will not exceed 2.50 to 1.00 on a pro forma basis, (iii) any secured Indebtedness assumed in such proposed Permitted Acquisition is purchase money Indebtedness or Capitalized Leases secured only by the assets of the Target acquired with the proceeds of such purchase money Indebtedness or Capitalized Leases and (iv) no Default will exist;

(e)                                   The business and assets of the Target shall be free of Liens, except Liens permitted in connection with Indebtedness permitted to be assumed by paragraph (d) of this definition and Liens permitted under Section 9.8; and

(f)                                     All necessary or appropriate third party and government waivers and consents relating to the Permitted Acquisition have been received.

“ 2005 Lease Documents ” is defined in Section 9.28.

“ 2005 Lease Obligations ” means the Indebtedness of the Borrowers under the 2005 Lease Documents.

“ 2005 Lease Transaction ” means the lease transaction entered into after July 15, 2005 and on or before December 31, 2005, by the Borrowers and certain other parties pursuant to the 2005 Lease Documents, for the purpose of constructing, financing the construction of, and leasing to CH2M Hill, Inc. a new building for the Borrowers in Douglas County, Colorado.

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2.                                        The initial paragraph of the Credit Agreement is hereby amended and restated in its entirety to read as follows:

“This Agreement, dated as of July 28, 2003, is entered into by and among CH2M HILL Companies, Ltd., an Oregon corporation, CH2M HILL, Inc., a Florida corporation, Operations Management International, Inc., a California corporation, and CH2M Hill Industrial Design & Construction, Inc., an Oregon corporation (each a “ Borrower ,” and collectively, the “ Borrowers ”), the Lenders from time to time party hereto, each in its capacity as a Lender and in its capacity as an Issuing Bank, and Wells Fargo Bank, National Association, in its capacity as a Lender, in its capacity as an Issuing Bank, in its capacity as agent for itself and the other Lenders and in its capacity as lead arranger.  The parties agree as follows:”

3.                                        Section 2.4 of the Credit Agreement is hereby amended and restated to read in its entirety as follows:

“2.4                            Letters of Credit .

2.4.1                         Issuance of Letters of Credit .  Subject to all terms and conditions of this Agreement and so long as no Default exists, from time to time on and after the Initial Closing Date and prior to the Final Maturity Date, each Issuing Bank will issue for the account of the Borrowers standby and documentary letters of credit (the “ Letters of Credit ”).  No Issuing Bank will issue a Letter of Credit to the extent that the face amount of such requested Letter of Credit exceeds the LC Available Credit.

2.4.2                         Requests for Letters of Credit .  The Parent, on behalf of the applicable Borrower, may from time to time request a Letter of Credit to be issued (or amended, renewed or extended) by providing a notice from an Authorized Representative to the applicable Issuing Bank and the Agent which is actually received by both not less than three Banking Days prior to the requested Closing Date for such Letter of Credit specifying (a) the amount of the requested Letter of Credit, (b) the applicable Borrower, (c) the beneficiary thereof, (d) the requested Closing Date, (e) the applicable Issuing Bank, (f) the requested currency, if not in United States Dollars, (g) the principal terms of the text for such Letter of Credit and (h) any other information reasonably requested by the applicable Issuing Bank.  Following receipt of such notice, if a Foreign Currency is requested, the Agent shall calculate on the Closing Date the U.S. Dollar Equivalent of the face amount of such Letter of Credit as of the Closing Date, and shall promptly notify the Lenders of the amount thereof.  The issuance or amendment, renewal or extension of each Letter of Credit by an Issuing Bank shall, in addition to the conditions precedent set forth in Section 8.2 (the satisfaction of which no Issuing Bank shall have any duty to ascertain), be subject to the condition precedent that the applicable Issuing Bank shall have given the Agent written notice that the Parent has delivered to the Issuing Bank an executed Letter of Credit Agreement acceptable to such Issuing Bank and that such Letter of Credit is satisfactory to such Issuing Bank or that the Issuing Bank has waived such requirements.  In the event of any conflict between the terms of this Agreement and the terms of any Letter of Credit Agreement, the terms of this Agreement shall control.  Each Letter of Credit will be issued by forwarding it to the applicable Borrower or to such other Person

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as directed in writing by an Authorized Representative.  The Issuing Bank shall promptly deliver a copy of each Letter of Credit to the Agent.

2.4.3                         Form and Expiration of Letters of Credit .  Each Letter of Credit issued under this Section 2.4 and each draft accepted or paid under such a Letter of Credit will be issued, accepted or paid, as the case may be, by the applicable Issuing Bank at its principal office.  No Letter of Credit will provide for the payment of drafts drawn thereunder (and no draft will be payable) at a date which is later than the Final Maturity Date.  Each Letter of Credit and each draft accepted under a Letter of Credit will be in such form and minimum amount, and will contain such terms, as the applicable Issuing Bank and the applicable Borrower may agree upon at the time such Letter of Credit is issued, including a requirement of not less than three Banking Days after presentation of a draft before payment must be made thereunder.

2.4.4                         Lenders’ Participation in Letters of Credit .  Upon the issuance of any Letter of Credit (or an amendment of a Letter of Credit increasing the amount thereof), a participation therein, in an amount equal to each Lender’s Percentage Interest multiplied by the face amount of such Letter of Credit (which amount shall be the U.S. Dollar Equivalent of such face amount, if the Letter of Credit is issued in a Foreign Currency and which amount will change from time to time as the U.S. Dollar Equivalent of the face amount of such Letter of Credit changes), will automatically be deemed granted by the Issuing Bank to each Lender on the date of such issuance and the Lenders will automatically be obligated, as set forth in Section 2.4.6 and Section 13.4, to reimburse such Issuing Bank to the extent of their respective Percentage Interests in such Letter of Credit for all obligations incurred by such Issuing Bank to third parties in respect of such Letter of Credit not reimbursed by the Borrowers.  The Agent will send to each Lender a report regarding the participations in Letters of Credit outstanding during each month.  Each Lender acknowledges and agrees that its obligation to acquire participations pursuant to this Section 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.

2.4.5                         Presentation .  Upon receipt from the beneficiary of any Letter of Credit of any demand for payment under such Letter of Credit, the applicable Issuing Bank shall notify the Agent by telephone (confirmed by facsimile) of such demand for payment and whether such Issuing Bank has made or will make a payment thereunder.  The Agent shall promptly notify the Parent and each other Lender as to the amount paid or to be paid by the applicable Issuing Bank as a result of such demand and the proposed payment date.  If the Letter of Credit was issued in a Foreign Currency, the Agent shall include in such notice a calculation of the anticipated U.S. Dollar Equivalent of such amount on the proposed payment date.  The responsibility of each Issuing Bank to the Borrowers and each Lender shall be only to determine that the documents (including each demand for payment) delivered under each Letter of Credit in connection with such presentment shall be in conformity in all material respects with such Letter of Credit.  Except insofar as written instructions actually received are given by the applicable Borrower expressly to

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the contrary with regard to, and prior to, the Issuing Bank’s issuance of any Letter of Credit for the account of the applicable Borrower and such contrary instructions are reflected in such Letter of Credit, the Issuing Bank may honor as complying with the terms of the Letter of Credit and with this Agreement any drafts or other documents otherwise in order signed or issued by an administrator, executor, conservator, trustee in bankruptcy, debtor in possession, assignee for benefit of creditors, liquidator, receiver or other legal representative of the party authorized under such Letter of Credit to draw or issue such drafts or other documents.  Each Issuing Bank shall endeavor to exercise the same care in the issuance and administration of the Letters of Credit issued by it as it does with respect to letters of credit in which no participations are granted, it being understood that in the absence of any gross negligence or willful misconduct by the applicable Issuing Bank, each Lender shall be unconditionally and irrevocably liable without regard to the occurrence of any Default or any condition precedent whatsoever, to reimburse the applicable Issuing Bank as set forth in Section 2.4.6.  No Lender shall hereby be precluded from asserting any claim for direct (but not consequential) damages suffered by such Lender to the extent, but only to the extent, caused by (i) the willful misconduct or gross negligence of the applicable Issuing Bank in determining whether a request presented under any Letter of Credit issued by it complied with the terms of such Letter of Credit or (ii) the applicable Issuing Bank’s failure to pay under any Letter of Credit issued by it after the presentation to it of a request strictly complying with the terms and conditions of such Letter of Credit.

2.4.6                         Payment of Drafts .  At such time as the applicable Issuing Bank makes any payment on a draft presented or accepted under a Letter of Credit, the Borrowers shall, on demand, pay to the Agent the amount of such payment either, at the Borrower’s election, (a) through a Revolving Credit Loan, subject to the terms and conditions of this Agreement, including satisfaction of the conditions precedent set forth in this Agreement to the making of a Revolving Credit Loan, and so long as no Default exists, or (b) in immediately available funds.  If the Letter of Credit was issued in a Foreign Currency, the Agent shall determine the U.S. Dollar Equivalent of such amount on the proposed payment date.  If the Borrowers fail to notify the Agent of their election as set forth above on the date such demand is made, such amount shall be considered a Revolving Credit Loan under Section 2.1.1 and part of the Loans as if the Borrowers had paid in full the amount required with respect to the Letter of Credit by borrowing such amount under Section 2.1.1.  In that event, the Agent shall notify each Lender that such Lender is to make a Revolving Credit Loan to the Borrowers (which shall consist of Base Rate Loans) in an amount equal to the Lender’s Percentage Interest of the aggregate principal amount of such Revolving Credit Loan; and, regardless of whether the conditions precedent set forth in this Agreement to the making of a Revolving Credit Loan are then satisfied, each Lender (other than the applicable Issuing Bank) will disburse directly to the applicable Issuing Bank, its Percentage Interest of the aggregate principal amount of such Revolving Credit Loan, prior to 12:00 noon (Denver time), in immediately available funds on the Banking Day next succeeding the date such notice is given to such Lender.  The proceeds of such Revolving Credit Loan shall be applied to repay the amount required by the first sentence of this Section.  Promptly following receipt by the Agent of any payment from the Borrowers pursuant to this Section, the Agent shall distribute such payment to the

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applicable Issuing Bank or, to the extent the Lenders have made payments pursuant to this Section to reimburse the applicable Issuing Bank, then to such Lenders and to the applicable Issuing Bank as their interests may appear.  Any payment made by a Lender pursuant to this Section to reimburse the applicable Issuing Bank (other than the funding of a Revolving Credit Loan as contemplated above) shall not constitute a Loan and shall not relieve the Borrowers of their obligation to reimburse the applicable Issuing Bank.

2.4.7                         Subrogation .  Upon any payment by the applicable Issuing Bank under any Letter of Credit and until the reimbursement of such Issuing Bank by the Borrowers with respect to such payment, such Issuing Bank will be entitled to be subrogated to, and to acquire and retain, the rights which the Person to whom such payment is made may have against the Borrowers, all for the benefit of the Lenders.  The Borrowers will take such action as the applicable Issuing Bank may reasonably request, including requiring the beneficiary of any Letter of Credit to execute such documents as the applicable Issuing Bank may reasonably request, to assure and confirm to such Issuing Bank such subrogation and such rights, including the rights, if any, of the beneficiary to whom such payment is made in accounts receivable, inventory and other properties and assets of any Obligor.

2.4.8                         Modification, Consent, Etc.   If the Borrowers request or consent in writing to any modification or extension of any Letter of Credit, or waive any failure of any draft, certificate or other document to comply with the terms of such Letter of Credit, and if the applicable Issuing Bank consents thereto, such Issuing Bank will be entitled to rely on such request, consent or waiver.  This Agreement will be binding upon the Borrowers with respect to such Letter of Credit as so modified or extended, and with respect to any action taken or omitted by the Agent or the applicable Issuing Bank pursuant to any such request, consent or waiver.

2.4.9                         Obligations Absolute .  The Borrowers’ obligations under this Section 2.4 shall be absolute and unconditional under any and all circumstances and irrespective of any setoff, counterclaim or defense to payment which any Borrower may have or have had against any Issuing Bank, any Lender or any beneficiary of a Letter of Credit.  The Borrowers further agree with the Issuing Banks and the Lenders that the Issuing Banks and the Lenders shall not be responsible for, and the reimbursement obligations of the Borrowers under any Letter of Credit shall not be affected by, among other things, the validity or genuineness of documents or of any endorsements thereon, even if such documents should in fact prove to be in any or all respects invalid, fraudulent or forged, or any dispute between or among any Borrower, any of their Affiliates, the beneficiary of any Letter of Credit or any financing institution or other party to whom any Letter of Credit may be transferred or any claims or defenses whatsoever of any Borrower or of any of their Affiliates against the beneficiary of any Letter of Credit or any such transferee.  The Issuing Banks shall not be liable for any error, omission, interruption or delay in transmission, dispatch or delivery of any message or advice, however transmitted, in connection with any Letter of Credit.  The Borrowers agree that any action taken or omitted by any Issuing Bank or any Lender under or in connection with each Letter of Credit and the related drafts and documents, if done without gross negligence or willful misconduct, shall be binding upon each Borrower and shall not put any Issuing Bank or

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any Lender under any liability to any Borrower.  Nothing in this Section 2.4.9 is intended to limit the right of the Borrowers to make a claim against any Issuing Bank for damages as contemplated by the proviso to the first sentence of Section 2.4.10.

2.4.10                   Actions of Issuing Banks .  Each Issuing Bank shall be entitled to rely, and shall be fully protected in relying, upon any Letter of Credit, draft, writing, resolution, notice, consent, certificate, affidavit, letter, cablegram, telegram, telecopy, telex or teletype message, statement, order or other document believed by it to be genuine and correct and to have been signed, sent or made by the proper Person or Persons, and upon advice and statements of legal counsel, independent accountants and other experts selected by such Issuing Bank.  Each Issuing Bank shall be fully justified in failing or refusing to take any action under this Agreement unless it shall first have received such advice or concurrence of the Required Lenders as it reasonably deems appropriate or it shall first be indemnified to its reasonable satisfaction by the Lenders against any and all liability and expense which may be incurred by it by reason of taking or continuing to take any such action. Notwithstanding any other provision of this Section 2.4, each Issuing Bank shall in all cases be fully protected in acting, or in refraining from acting, under this Agreement in accordance with a request of the Required Lenders, and such request and any action taken or failure to act pursuant thereto shall be binding upon the Lenders and any future holders of a participation in any Letter of Credit.

2.4.11                   Indemnification .  Each Lender severally agrees to indemnify each Issuing Bank (to the extent not promptly reimbursed by the Borrowers) to the extent of such Lender’s Percentage Interest from and against any and all liabilities, obligations, losses, damages, penalties, actions, judgments, suits, costs, expenses or disbursements of any kind or nature whatsoever that may be imposed on, incurred by, or asserted against such Issuing Bank by reason of or in connection with the issuance, execution and delivery or transfer of or payment or failure to pay under any Letter of Credit or any actual or proposed use of any Letter of Credit, including, without limitation, any claims, damages, losses, liabilities, costs or expenses which any Issuing Bank may incur by reason of or in connection with (a) the failure of any other Lende