Exhibit 4.9 FOURTH AMENDMENT TO THIRD AMENDED AND RESTATED SECURED CREDIT AGREEMENT THIS FOURTH AMENDMENT TO THIRD AMENDED AND RESTATED SECURED CREDIT AGREEMENT (this "AMENDMENT") is entered into as of October 27, 2000, among QUANTA SERVICES, INC., a Delaware corporation ("BORROWER"), the Lenders, as defined below, and BANK OF AMERICA, N.A., f/k/a NationsBank, N.A., as administrative agent for the Lenders (in such capacity, the "AGENT"). Capitalized terms used but not defined in this Amendment have the meaning given such terms in the Credit Agreement (defined below). RECITALS A. The Borrower is party to that certain Third Amended and Restated Secured Credit Agreement dated as of June 14, 1999 (as amended by the First Amendment dated as of September 21, 1999, the Second Amendment dated as of March 21, 2000, the Third Amendment and Consent dated as of June 15, 2000, and as may be amended, restated or supplemented from time to time, the "CREDIT AGREEMENT"), among the Borrower, Agent, and the lenders from time to time parties thereto (each a "LENDER" collectively, "LENDERS"). B. The Borrower has requested that the "LC Commitment Amount" as defined in Section 1.1 of the Credit Agreement be increased from $15,000,000 to $50,000,000. C. The Borrower and the Lenders have agreed to amend the Credit Agreement to amend and restate the definition of "LC Commitment Amount" to accommodate such increase, subject to the terms and conditions set out in this Amendment. NOW THEREFORE, in consideration of the premises and other good and valuable consideration, the receipt and sufficiency of which are acknowledged, the undersigned agree as follows: 1. Amendment. The definition of "LC Commitment Amount" contained in Section 1.1 of the Credit Agreement is amended and restated in its entirety as follows (with the underlined portions showing new or revised language): "L/C COMMITMENT AMOUNT" means $50,000,000, as such amount may be reduced from time to time pursuant to the terms of this Agreement. 2. Conditions. This Amendment shall not be effective until each of the following have been delivered to the Agent or the following conditions have been otherwise satisfied in the Agent's sole discretion: (a) this Amendment signed by the Borrower, the Guarantors, and the Majority Lenders; (b) the Borrower has delivered to the Agent for the benefit of the Lenders a certificate from the Borrower that no Default or Potential Default exists under the Credit Agreement; and (c) such other documents as the Agent may reasonably request. 3. Fees and Expenses. The Borrower agrees to pay the reasonable fees and expenses of counsel to Agent for services rendered in connection with the preparation, negotiation and execution of this Amendment. 4. Representations and Warranties. The Borrower and Guarantors represent and warrant to the Lenders that they possess all requisite power and authority to execute, deliver and comply with the terms of this Amendment, which has been duly authorized and approved by all requisite corporate action on the part of the Borrower and Guarantors, for which no consent of any Person is required, and which will not violate their respective organizational documents, and agree to furnish the Lenders with evidence of such authorization and approval upon request. The Borrower and Guarantors further represent and warrant to the Lenders that (a) the representations and warranties in each Credit Document to which they are a party are true and correct in all material respects on and as of the date of this Amendment as though made on the date of this Amendment (except to the extent that (i) such representations and warranties speak to a specific date or (ii) the facts on which such representations and warranties are based have been changed by transactions contemplated by the Credit Agreement), (b) it is in full compliance with all covenants and agreements contained in each Credit Document to which it is a party, and (c) no Default or Event of Default has occurred and is continuing. 5. Scope of Amendment; Reaffirmation; Release. Except as affected by this Amendment, the Credit Documents are unchanged and continue in full force and effect. However, in the event of any inconsistency between the terms of the Credit Agreement as hereby amended and any other Credit Document, the terms of the Credit Agreement shall control and such other document shall be deemed to be amended hereby to conform to the terms of the Credit Agreement. All references to the Credit Agreement shall refer to the Credit Agreement as amended by this Amendment. The Borrower and Guarantors hereby reaffirm their respective obligations under, and agree that, all Credit Documents to which they are a party remain in full force and effect and continue to evidence their respective legal, valid and binding obligations enforceable in accordance with their terms (as the same are affected by this Amendment). The Borrower and Guarantors hereby release the Lenders from any liability for actions or failures to act in connection with the Credit Documents prior to the date hereof. This Amendment shall be binding upon and inure to the benefit of each of the undersigned and their respective successors and permitted assigns. 6. Miscellaneous. (a) No Waiver of Defaults. This Amendment does not constitute a waiver of, or a consent to, any present or future violation of or default under, any provision of the Credit Documents, or a waiver of the Lenders' right to insist upon future compliance with each term, covenant, condition and provision of the Credit Documents, and the Credit Documents shall continue to be binding upon, and inure to the benefit of, the Borrower, Guarantors, and the Lenders and their respective successors and assigns. (b) Form. Each agreement, document, instrument or other writing to be furnished Agent under any provision of this instrument must be in form and substance satisfactory to Agent and its counsel. (c) Multiple Counterparts. This Amendment may be executed in any number of counterparts with the same effect as if all signatories have signed the same document. All counterparts must be construed together to constitute one and the same instrument. 2 (d) Governing Law. This Amendment and the other Credit Documents must be construed-and their performance enforced-under Texas law. 7. Entirety. THE CREDIT DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE BORROWER, GUARANTORS AND THE LENDERS AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS BY THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS AMONG THE PARTIES. [SIGNATURES AND GUARANTORS' CONSENT AND AGREEMENT APPEAR ON FOLLOWING PAGES.] 3 The Amendment is executed as of the date set out in the preamble to this Amendment. QUANTA SERVICES, INC. By: /s/ James H. Haddox ------------------------------------------- James H. Haddox Chief Financial Officer BANK OF AMERICA, N.A., as Administrative Agent By: /s/ David A. Johanson ------------------------------------------- David A. Johanson, Vice President BANK OF AMERICA, N.A., as a Lender By: /s/ Craig S. Wall ------------------------------------------- Craig S. Wall Senior Vice President BANK ONE, TEXAS, NATIONAL ASSOCIATION, as a Documentation Agent and as a Lender By: /s/ Greg Smothers ------------------------------------------- Greg Smothers Vice President FLEET NATIONAL BANK (F/K/A BANK BOSTON, N.A.), as a Documentation Agent and as a Lender By: /s/ Michael M. Parker ------------------------------------------- Michael M. Parker Managing Director CREDIT LYONNAIS NEW YORK BRANCH, as a Managing Agent and as a Lender By: /s/ Attila Koc ------------------------------------------- Attila Koc Senior Vice President THE BANK OF NOVA SCOTIA, as a Managing Agent and as a Lender By: /s/ F C H Ashby ------------------------------------------- F C H Ashby Senior Manager Loan Operations NATIONAL CITY BANK, as a Lender By: /s/ Michael J. Durbin ------------------------------------------- Michael J. Durbin Vice President LASALLE BANK NATIONAL ASSOCIATION, as a Lender By: /s/ Richard J. Kress ------------------------------------------- Richard J. Kress Vice President FIRST UNION NATIONAL BANK, as a Lender By: /s/ Mark B. Felkler ------------------------------------------- Mark B. Felkler Senior Vice President COMERICA BANK, as a Lender By: /s/ Mark B. Grover ------------------------------------------- Mark B. Grover Vice President THE BANK OF TOKYO-MITSUBISHI, LTD., as a Lender By: /s/ J. Fort ------------------------------------------- J. Fort Vice President CHASE BANK OF TEXAS, N.A., as a Lender By: /s/ James. R. Dolphin ------------------------------------------- James R. Dolphin Senior Vice President GUARANTY FEDERAL BANK, F.S.B., as a Lender By: /s/ Kevin J. Hanigan ------------------------------------------- Kevin J. Hanigan Senior Vice President SUNTRUST BANK, ATLANTA, as a Lender By: /s/ Frank A. Coe ------------------------------------------- Frank A. Coe Vice President By: ------------------------------------------- Name: -------------------------------------- Title: ------------------------------------- BANKERS TRUST COMPANY, as a Lender By: /s/ Diane F. Rolfe ------------------------------------------- Diane F. Rolfe Vice President GUARANTORS' CONSENT AND AGREEMENT As an inducement to the Lenders to execute, and in consideration of the Lenders' execution of this Amendment, each of the undersigned hereby consents to this Amendment and agrees that the same shall in no way release, diminish, impair, reduce or otherwise adversely affect the obligations and liabilities of the undersigned under their respective Guaranties described in the Credit Agreement executed by the undersigned, or any agreements, documents or instruments executed by any of the undersigned, all of which obligations and liabilities are, and shall continue to be, in full force and effect. This consent and agreement shall be binding upon the undersigned, and their respective successors and assigns, and shall inure to the benefit of the Lenders, and their respective successors and assigns. Advanced Communication Technologies, Inc. Arby Construction, Inc. Austin Trencher, Inc. CCLC, Inc. Computapole, Inc. Conti Communications, Inc. Croce Electric Company, Inc. Crown Fiber Communications, Inc. Dillard Smith Construction Company Driftwood Electrical Contractors, Inc. Edwards Pipeline Company, Inc. Environmental Professional Associates, Limited Fiber Technology, Inc. Five Points Construction Company GEM Engineering Co., Inc. Golden State Utility Co. H.L. Chapman Pipeline Construction, Inc. Haines Construction Company Harker & Harker, Inc. Intermountain Electric, Inc. IRBY Construction Company Line Equipment Sales Co. Logical Link, Inc. Manuel Bros., Inc. Mears Group, Inc. Mears Pipeline Services, Inc. Metro Underground Services, Inc. NetCom Management Group, Inc. Network Communications Services, Inc. North Pacific Construction Co., Inc. North Sky Communications, Inc. Northern Line Layers, Inc. Pac West Construction, Inc. PAR Electrical Contractors, Inc. P.D.G. Electric Company Potelco, Inc. QSI, Inc. Quanta XVII Acquisition Inc. Quanta XLI Acquisition, Inc. Quanta XLII Acquisition, Inc. Quanta XLIII Acquisition, Inc. Quanta XLV Acquisition, Inc. Quanta XLVI Acquisition, Inc. Quanta XLVII Acquisition, Inc. Quanta XLVIII Acquisition, Inc. Quanta L Acquisition, Inc. Quanta LI Acquisition, Inc. Quanta LII Acquisition, Inc. Quanta LIII Acquisition, Inc. Quanta LIV Acquisition, Inc. Quanta LV Acquisition, Inc. Quanta LVI Acquisition, Inc. Quanta LVII Acquisition, Inc. Quanta LVIII Acquisition, Inc. Quanta LIX Acquisition, Inc. Quanta LX Acquisition, Inc. Quanta LXI Acquisition, Inc. Quanta LXII Acquisition, Inc. Quanta LXIII Acquisition, Inc. Quanta LXIV Acquisition, Inc. Quanta LXV Acquisition, Inc. Quanta LXVI Acquisition, Inc. Quanta LXVII Acquisition, Inc. Quanta LXVIII Acquisition, Inc. Quanta LXIX Acquisition, Inc. Quanta LXX Acquisition, Inc. Quanta LXXI Acquisition, Inc. Quanta LXXII Acquisition, Inc. Quanta LXXIII Acquisition, Inc. Quanta LXXIV Acquisition, Inc. Quanta Delaware, Inc. Quanta Utility Installation Co., Inc, R. A. Waffensmith & Co., Inc. Ranger Directional, Inc. S.K.S. Pipeliners, Inc. Seaward Corporation Southeast Pipeline Construction, Inc. Spalj Construction Company Specialty Drilling Technology, Inc. Sullivan Welding, Inc. Sumter Builders, Inc. SynerTec Inc. Telecom Network Specialists, Inc. The Ryan Company, Inc. Tom Allen Construction Company TRANS TECH Electric, Inc. Trawick Construction Co. TTM, Inc. TVS Systems, Inc. Underground Construction Co., Inc. Utilco, Inc. Utilities Construction Co., Inc. VCI Telecom, Inc. W.C. Communications, Inc. W.H.O.M. Corporation Wade D. Taylor, Inc. World Fiber, Inc. By: /s/ Brad Eastman ------------------------------------------------- Brad Eastman, President or Vice President of each Guarantor Coast To Coast, LLC By: Environmental Professional Associates, Limited, Its Member By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President By: Quanta Services, Inc., Its Member By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President Lake Norman Pipeline, LLC By: Edwards Pipeline Company, Inc., Its Member By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President Mears/CPG, LLC By: Mears Group, Inc., Its Member By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President Mears Engineering, LLC By: Mears Group, Inc., Its Member By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President Mears/HDD, LLC By: Mears Group, Inc., Its Member By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President Mears Services, LLC By: Mears Group, Inc., Its Member By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President Quanta Services Management Partnership, L.P. By: QSI, Inc., Its General Partner By: /s/ Brad Eastman --------------------------------- Brad Eastman, Vice President