Exhibit 99.3

EXECUTION VERSION

SECOND AMENDED AND RESTATED

PLEDGE AGREEMENT

THIS SECOND AMENDED AND RESTATED PLEDGE AGREEMENT (this “Agreement”) dated as of August 2, 2011 is by and among the parties identified as “Pledgors” on the signature pages attached hereto and such other parties as may from time to time become Pledgors hereunder (each a “Pledgor” and collectively the “Pledgors”) and Bank of America, N.A., as administrative agent (in such capacity, the “Administrative Agent”), for the ratable benefit of the Secured Parties (defined below) and amends and restates that certain Amended and Restated Pledge Agreement, dated as of June 12, 2006 (as amended or otherwise modified prior to the date hereof, the “Existing Pledge Agreement”), among the Borrower (defined below), the pledgors from time to time party thereto, and Bank of America, N.A., as administrative agent, which Existing Pledge Agreement amended and restated that certain Pledge Agreement, dated as of December 19, 2003 (as amended or otherwise modified), among the Borrower, the pledgors from time to time party thereto, and Bank of America, N.A., as administrative agent.

RECITALS:

A. Quanta Services, Inc., a Delaware corporation (the “Borrower”), the Guarantors, the Lenders, and Bank of America, N.A., as Administrative Agent, Swing Line Lender and L/C Issuer have entered into that certain Second Amended and Restated Credit Agreement dated as of the date hereof (as amended, modified, supplemented or restated from time to time, the “Credit Agreement”).

B. This Agreement is required under the terms of the Credit Agreement.

C. Each Pledgor will derive substantial direct and indirect benefit from the Credit Agreement.

NOW THEREFORE, in consideration of the premises and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

SECTION 1. Definitions. Unless otherwise defined herein, capitalized terms used herein and not defined have the same meaning assigned to such terms in the Credit Agreement. As used in this Agreement:

“Collateral” is defined in Section 2.1.

“Collateral Proceeds” is defined in Section 2.1(f).

“Collateral Termination Date” means the first date on which no Loan or Credit Extension is outstanding under the Credit Agreement, the Commitments have been terminated, and no other Obligations under any Loan Document remain unpaid or unsatisfied (other than any contingent indemnity obligations that, by their terms, survive the termination of the Credit Agreement).

“Event of Default” is defined in Section 6.1.

“Pledged Shares” is defined in Section 2.1(a).

“Secured Obligations” means, without duplication, (i) the Obligations, and (ii) all costs and expenses incurred in connection with enforcement and collection of the Secured Obligations described in the foregoing clause (i), including, without limitation, reasonable attorneys’ fees and disbursements.

“Secured Parties” means, collectively, the Lenders, the Swap Banks, the Treasury Management Banks and any other holder of the Secured Obligations, and “Secured Party” means any one of them.

“UCC” means the Uniform Commercial Code.

“Voting Stock” is defined in Section 2.1.

SECTION 2. Security Interest and Pledge.

2.1 Security Interest and Pledge. Subject to the terms of this Agreement and the Credit Agreement, and to secure the Secured Obligations, each Pledgor hereby pledges, assigns, grants, conveys and transfers to the Administrative Agent for the ratable benefit of the Secured Parties a continuing first priority security interest in, and a right of set-off against, any and all of such Pledgor’s rights, title and interest in, to and under the following property, whether now existing or owned, acquired or arising hereafter (collectively, the “Collateral”):

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provided, that in no event shall the Administrative Agent’s security interest encumber capital stock or membership interests of any of the Companies which is (i) a “controlled foreign corporation” (within the meaning of the Internal Revenue Code) representing more than sixty-five percent (65%) of the combined voting power of all classes of stock or membership interests entitled to vote (the “Voting Stock”) of any such entity, or (ii) Excluded Property.

Without limiting the generality of the foregoing, it is hereby specifically understood and agreed that a Pledgor may from time to time hereafter deliver additional Capital Stock to the Administrative Agent as collateral security for the Secured Obligations. Upon delivery to the Administrative Agent, such additional Capital Stock shall be deemed to be part of the Collateral of such Pledgor and shall be subject to the terms of this Pledge Agreement whether or not Schedule 2.1(a) is amended to refer to such additional Capital Stock.

2.2 Delivery of the Collateral. Each Pledgor hereby agrees that:

SECTION 3. Representations and Warranties. Each Pledgor represents and warrants to the Administrative Agent for the benefit of the Secured Parties, that so long as any of the Secured Obligations remain unpaid or unsatisfied (other than any contingent indemnity obligations that, by their terms, survive the termination of the Credit Agreement) and until all of the Revolving Commitments have been terminated:

3.1 Title. Such Pledgor owns or, with respect to Collateral acquired after the date hereof, such Pledgor will own, legally and beneficially, the Collateral free and clear of any Lien, except for the security interest granted hereunder and Permitted Liens. Such Pledgor has the unrestricted right to pledge the Collateral as contemplated hereby, and there exists no “adverse claim” within the meaning of Section 8-102 of the UCC with respect to the Collateral.

3.2 Organization and Authority. Neither the execution, delivery or performance by such Pledgor of this Agreement nor compliance by it with the terms and provisions hereof, nor the consummation of the transactions contemplated herein, will (i) contravene any applicable provision of any Law or any order, writ, injunction or decree of any Governmental Authority or any arbitral award to which such Pledgor is a party; or (ii) conflict with or result in any breach of any material Contractual Obligation to which any Pledgor is a party or constitute a default under, or result in the creation of any Lien (other than pursuant to the Collateral Documents) upon any of the Property of any Pledgor.

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3.3 First Priority Perfected Security Interest. This Agreement has been duly authorized, executed and delivered by such Pledgor. This Agreement creates a valid security interest in favor of the Administrative Agent for the benefit of the Secured Parties in the Collateral. The taking of possession by the Administrative Agent of the certificates representing the Pledged Shares and all other certificates and instruments constituting Collateral will perfect and establish the first priority of the Administrative Agent’s security interest in the Pledged Shares consisting of certificated securities and, when properly perfected by filing or registration, in all other Collateral represented by such Pledged Shares and instruments securing the Secured Obligations. Except as set forth in this Section 3.3 and except as may be required by applicable foreign laws affecting the pledge of Capital Stock of Foreign Subsidiaries, no action is necessary to perfect or otherwise protect such security interest.

3.4 Partnership and Membership Interests. Except as previously disclosed to the Administrative Agent, none of the Pledged Shares consisting of partnership or limited liability company interests (i) is dealt in or traded on a securities exchange or in a securities market, (ii) by its terms expressly provides that it is a security governed by Article 8 of the UCC, (iii) is an investment company security, (iv) is held in a securities account or (v) constitutes a “Security” or a “Financial Asset” (as each such term is defined in the UCC).

3.5 No Consent. No consent of, or notice to, any other Person and no authorization, approval or other action by, and no notice to or filing with, any Governmental Authority is required for the grant by such Pledgor of the Liens granted hereby or for the execution, delivery or performance of this Agreement by such Pledgor, other than (a) the filing of financing statements and the filing of an investment act notice in connection with the Capital Stock of any Company organized in Canada, (b) such filings as may be necessary in connection with the Capital Stock of any company organized in a foreign jurisdiction other than Canada, (c) with respect to the assets or Capital Stock of any Subsidiary licensed by the Federal Communications Commission or otherwise authorized to provide telecommunications services, the prior approval of the Federal Communications Commission may be required if the assets or Capital Stock are transferred through foreclosure or otherwise, (d) with respect to the assets or Capital Stock of any Regulated Subsidiary, certain state public utility commission approvals may be required if the assets or Capital Stock are transferred through foreclosure or otherwise, and (e) except for such other consents, notices or filings that have been obtained or made or that as of the date hereof are not required to have been obtained or made and may be obtained or made, as the case may be, when necessary.

SECTION 4. Covenants. Each Pledgor covenants and agrees that so long as any of the Secured Obligations remain unpaid or unsatisfied (other than any contingent indemnity obligations that, by their terms, survive the termination of the Credit Agreement) and until all of the Revolving Commitments have been terminated:

4.1 Encumbrances. Except as permitted by the Credit Agreement, each Pledgor shall not create, permit, or suffer to exist, and shall defend the Collateral against, any Lien on the Collateral except the Lien of the Administrative Agent hereunder and except for Permitted Liens, and shall warrant and defend title to and ownership of the Collateral of such Pledgor at its own expense against the claims and demands of all other parties claiming an interest therein and defend such Pledgor’s rights in the Collateral and the Administrative Agent’s security interest in the Collateral against the claims of all persons and entities (other than any person or entity claiming by, through or under the Administrative Agent or any obligee of the Secured Obligations).

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4.2 Sale of Collateral. No Pledgor shall sell, assign, or otherwise dispose of the Collateral or any part thereof except as permitted by the Credit Agreement.

4.3 Dividends.

4.4 Further Assurances. At any time and from time to time, upon the request of the Administrative Agent, and at the sole expense of such Pledgor, such Pledgor shall promptly execute and deliver all such further instruments and documents and take such further action as the Administrative Agent may deem reasonably necessary or desirable to (a) preserve and perfect its security interest in the Collateral; (b) enable the Administrative Agent to exercise and enforce its rights and remedies hereunder in respect of the Collateral of such Pledgor; and (c) carry out the provisions and purposes of this Agreement, including, without limitation, (i) the execution and filing of such financing statements as the Administrative Agent may require and (ii) upon the occurrence and during the continuance of an Event of Default, if requested by the Administrative Agent, delivering to the Administrative Agent irrevocable proxies in respect of the Collateral of such Pledgor.

4.5 Inspection Rights. Upon reasonable notice from the Administrative Agent, each Pledgor shall permit the Administrative Agent and its representatives to examine, inspect, and copy such Pledgor’s books and records concerning ownership of the Collateral at any reasonable time during normal business hours and as often as the Administrative Agent may desire.

4.6 Books and Records. Each Pledgor shall mark its books and records (and shall cause the issuer of the Pledged Shares to mark its books and records) to reflect the security interest of the Administrative Agent for the benefit of the Secured Parties.

4.7 Receipt after Default. If any Collateral is received by any Pledgor during the continuance of an Event of Default, such Pledgor shall pay over to the Administrative Agent all such Collateral on the day received, including the cash and checks endorsed by such Pledgor evidencing the Collateral. Such Pledgor shall not commingle the Collateral with any other funds, proceeds or monies of such Pledgor, and shall keep such proceeds separate and apart from any other funds, proceeds or monies of such Pledgor and shall hold the Collateral in trust for the Administrative Agent until same shall be paid over to the Administrative Agent as agreed to herein.

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4.8 Pledge of Shares of Controlled Foreign Corporation.

4.9 Amendments. Such Pledgor shall not make or consent to any amendment or other modification or waiver with respect to any of the Collateral of such Pledgor or enter into any agreement or allow to exist any restriction with respect to any of the Collateral of such Pledgor that is prohibited under the Credit Agreement or any other Loan Document.

4.10 Compliance with Securities Laws. Such Pledgor shall file all reports and other information now or hereafter required to be filed by such Pledgor with the United States Securities and Exchange Commission and any other state, federal or foreign agency in connection with such Pledgor’s ownership of the Collateral of such Pledgor.

4.11 Issuance or Acquisition of Capital Stock. Such Pledgor shall not, without executing and delivering, or causing to be executed and delivered, to the Administrative Agent such agreements, documents and instruments as the Administrative Agent may reasonably request for the purpose of perfecting its security interest therein, issue or acquire any Capital Stock constituting Collateral consisting of an interest in a partnership or a limited liability company that (i) is dealt in or traded on a securities exchange or in a securities market, (ii) by its terms expressly provides that it is a security governed by Article 8 of the UCC, (iii) is an investment company security, (iv) is held in a securities account or (v) constitutes a Security or a Financial Asset (as each is defined in the UCC).

SECTION 5. Rights of the Administrative Agent and Pledgor.

5.1 Power of Attorney. Each Pledgor hereby irrevocably and with the power of substitution constitutes and appoints the Administrative Agent on behalf of the Secured Parties and any officer or agent thereof, with full power of substitution, as its true and lawful attorney-in-fact with full irrevocable power and authority in the place and stead and in the name of each Pledgor or in its own name, from time to time in the Administrative Agent’s discretion during the continuance of an Event of Default and prior to the Collateral Termination Date, to take any and all action and to execute any and all documents and instruments which may be necessary or desirable to accomplish the purposes of this Agreement and, without limiting the generality of the foregoing, hereby gives the Administrative Agent the power and right on behalf of the Pledgors and in its own name to do any of the following after the occurrence and during the continuance of an Event of Default and to the extent permitted by applicable Laws, without notice to or the consent of the Pledgors:

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This power of attorney is a power coupled with an interest and shall be irrevocable. The Administrative Agent shall be under no duty to exercise or withhold the exercise of any of the rights, powers, privileges, and options expressly or implicitly granted to the Administrative Agent in this Agreement, and shall not

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be liable for any failure to do so or any delay in doing so. The Administrative Agent shall not be liable for any act or omission or for any error of judgment or any mistake of fact or Law in its individual capacity or in its capacity as attorney-in-fact except acts or omissions constituting or resulting from its willful misconduct or gross negligence. This power of attorney is conferred on the Administrative Agent solely to protect, preserve, and realize upon its security interest in the Collateral.

5.2 Voting Rights. Until written notice shall be given to the Pledgors in accordance with Section 6.2(d) that the Administrative Agent has exercised its rights under Section 6.2(d) to vote the Collateral (provided, however, if the Administrative Agent is prevented from providing such notice as a result of Section 362 of the United States Bankruptcy Code or similar Law the Pledgors shall be entitled to exercise such rights so long as no Event of Default shall have occurred and be continuing), a Pledgor shall be entitled to exercise any and all voting and other rights relating or pertaining to the Collateral or any part thereof and the Administrative Agent shall execute and deliver (or cause to be executed and delivered) to such Pledgor all such proxies and other instruments as such Pledgor may reasonably request for the purpose of enabling such Pledgor to exercise the voting and other rights which it is entitled to exercise pursuant to this sentence.

5.3 Collateral Proceeds. Until written notice shall be given to the Pledgors in accordance with Section 6.2(d) that the Administrative Agent has exercised its rights under Section 6.2(d) to vote the Collateral, each Pledgor shall be entitled to receive and collect for its own use all Collateral Proceeds.

5.4 Performance by the Administrative Agent of the Pledgors’ Obligations. If an Event of Default has occurred and is continuing or if a Pledgor fails to perform or comply with any of its agreements contained herein, the Administrative Agent may perform or cause performance of or compliance with such agreement and in so doing may expend such sums as the Administrative Agent may reasonably deem advisable in the performance thereof. All such expenses of the Administrative Agent so expended, together with interest thereon at the rate of interest provided in the Credit Agreement, shall be payable by the Pledgors on a joint and several basis to the Administrative Agent on demand and shall constitute Secured Obligations secured by this Agreement.

5.5 The Administrative Agent’s Duty of Care. Other than the exercise of reasonable care in the physical custody of the Collateral while held by the Administrative Agent hereunder, the Administrative Agent shall have no responsibility for or obligation or duty with respect to all or any part of the Collateral or any matter or proceeding arising out of or relating thereto, including, without limitation, any obligation or duty to collect any sums due in respect thereof or to protect or preserve any rights against prior parties or any other rights pertaining thereto, it being understood and agreed that Pledgor shall be responsible for preservation of all rights in the Collateral. Without limiting the generality of the foregoing, the Administrative Agent shall be conclusively deemed to have exercised reasonable care in the custody of the Collateral if the Administrative Agent takes such action, for purposes of preserving rights in the Collateral, as Pledgor may reasonably request in writing, but no failure or omission or delay by the Administrative Agent in complying with any such request by Pledgor, and no refusal by the Administrative Agent to comply with any such request by Pledgor, shall of itself be deemed to be a failure to exercise reasonable care.

SECTION 6. Events of Default and Remedies.

6.1 Events of Default. The Pledgors shall be in default under this Agreement upon the occurrence of and during the continuation of any of the events or conditions defined as Events of Default in the Credit Agreement (an “Event of Default”).

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6.2 Rights and Remedies. Prior to the Collateral Termination Date, upon the occurrence of an Event of Default and so long as the same shall be continuing, the Administrative Agent shall have the following rights and remedies to the extent not prohibited by applicable Laws:

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Because of applicable securities Laws, including without limitation, the Securities Act of 1933, as amended, and other applicable state securities Laws, there may be legal restrictions or limitations affecting attempts of the Administrative Agent to dispose of the Collateral in the enforcement of its rights and remedies hereunder, the Administrative Agent is hereby authorized by the Pledgors, but not obligated, upon the occurrence and during the continuance of an Event of Default, to the extent permitted by applicable Law, to sell all or any part of the Collateral at private sale, subject to investment letters or in any other manner which will not require the Collateral or any part thereof, to be registered in accordance with the Securities Act of 1933, as amended, or the rules and regulations promulgated thereunder, or any other applicable securities Law or regulation. The Pledgors specifically agree that under these circumstances, such a sale is a commercially reasonable method of disposition of the Collateral. The Administrative Agent is also hereby authorized by the Pledgors, but not obligated, to take such actions, give such notices, obtain such rulings and consents, and do such other things as the Administrative Agent may deem appropriate in the event of such a sale or disposition of any of the Collateral. The Pledgors acknowledge that the Administrative Agent may, in its reasonable discretion, approach a restricted number of potential purchasers and that a sale under such circumstances may yield a lower price for the Collateral or any part or parts thereof than would otherwise be obtainable if the same were registered and sold in the open market, the Pledgors agrees that such private sale shall constitute a commercially reasonable method of disposing of the Collateral in view of the time, expense, and potential liability to the parties of such transactions of registration of the Collateral in accordance with applicable securities Laws.

6.3 Application of Proceeds. Upon the occurrence and during the continuation of an Event of Default, any payments in respect of the Secured Obligations and any proceeds of the Collateral, when received by the Administrative Agent or any of the Secured Parties in cash or its equivalent, will be applied in reduction of the Secured Obligations in the order set forth in the Credit Agreement.

SECTION 7. Miscellaneous.

7.1 No Waiver; Cumulative Remedies. No failure on the part of the Administrative Agent to exercise and no delay in exercising, and no course of dealing with respect to, any right, power, privilege or remedy under this Agreement shall operate as a waiver thereof, nor shall any single or partial exercise of any right, power, privilege or remedy under this Agreement preclude any other or further exercise thereof or the exercise of any other right, power, privilege or remedy. To the fullest extent permitted by applicable Laws, the rights, powers, privileges and remedies provided for in this Agreement are cumulative and not exclusive of any rights, powers, privileges and remedies provided by Law. The Administrative Agent may exercise any right, power, privilege or remedy under this Agreement or under applicable Law against any Pledgor without enforcing any rights, powers, privileges or remedies against any other Pledgor under this Agreement or otherwise, each of the Pledgors expressly waiving any rights or requirements that the Administrative Agent or any Lender first enforce any right, power, privilege or remedy against the Borrower, any other Pledgor or any other Collateral for the Secured Obligations.

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7.2 Successors and Assigns. This Agreement shall be binding upon and inure to the benefit of each Pledgor and the Administrative Agent for the benefit of the Secured Parties and their respective successors, and assigns, except that none of the Pledgors may assign any of its rights or obligations under this Agreement without the prior written consent of the Required Lenders under the Credit Agreement except to the extent permitted by the Credit Agreement. To the fullest extent permitted by Law, each Pledgor hereby releases the Administrative Agent and each holder of the Secured Obligations, and their respective successors and assigns, from any liability for any act or omission relating to this Agreement or the Collateral, except for any liability arising from the gross negligence or willful misconduct of the Administrative Agent or such holder, or their respective officers, employees or agents.

7.3 Notices. All notices required or permitted to be given under this Agreement shall be given as provided in Section 11.02 of the Credit Agreement.

7.4 Governing Law; Submission to Jurisdiction.

(a) THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK; PROVIDED THAT THE PARTIES HERETO SHALL RETAIN ALL RIGHTS ARISING UNDER FEDERAL LAW.

(b) ANY LEGAL ACTION OR PROCEEDING WITH RESPECT TO THIS AGREEMENT OR ANY OTHER LOAN DOCUMENT MAY BE BROUGHT IN THE COURTS OF THE STATE OF NEW YORK SITTING IN NEW YORK, NEW YORK OR OF THE UNITED STATES FOR THE SOUTHERN DISTRICT OF SUCH STATE, AND BY EXECUTION AND DELIVERY OF THIS AGREEMENT, EACH PLEDGOR AND THE ADMINISTRATIVE AGENT, ON BEHALF OF ITSELF AND EACH LENDER, CONSENTS, FOR ITSELF AND IN RESPECT OF ITS PROPERTY, TO THE NON-EXCLUSIVE JURISDICTION OF THOSE COURTS. EACH PLEDGOR AND THE ADMINISTRATIVE AGENT, ON BEHALF OF ITSELF AND EACH LENDER, IRREVOCABLY WAIVES ANY OBJECTION, INCLUDING ANY OBJECTION TO THE LAYING OF VENUE OR BASED ON THE GROUNDS OF FORUM NON CONVENIENS, WHICH IT MAY NOW OR HEREAFTER HAVE TO THE BRINGING OF ANY ACTION OR PROCEEDING IN SUCH JURISDICTION IN RESPECT OF THIS AGREEMENT OR ANY OTHER LOAN DOCUMENT OR OTHER DOCUMENT RELATED THERETO. EACH PLEDGOR AND THE ADMINISTRATIVE AGENT, ON BEHALF OF ITSELF AND EACH LENDER, WAIVES PERSONAL SERVICE OF ANY SUMMONS, COMPLAINT OR OTHER PROCESS, WHICH MAY BE MADE BY ANY OTHER MEANS PERMITTED BY THE LAW OF SUCH STATE.

7.5 Waiver of Right to Trial by Jury.

EACH PARTY HERETO HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN ANY LEGAL PROCEEDING DIRECTLY OR INDIRECTLY ARISING OUT OF OR RELATING TO THIS AGREEMENT OR ANY OTHER LOAN DOCUMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY (WHETHER BASED ON CONTRACT, TORT OR ANY OTHER THEORY). EACH PARTY HERETO (A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PERSON HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PERSON WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER AND (B) ACKNOWLEDGES THAT IT AND THE OTHER PARTIES HERETO HAVE BEEN INDUCED TO ENTER INTO THIS AGREEMENT AND THE OTHER LOAN DOCUMENTS BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION.

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7.6 Headings. The headings, captions, and arrangements used in this Agreement are for convenience only and shall not affect the interpretation of this Agreement.

7.7 Survival of Representations and Warranties. All representations and warranties made in this Agreement or in any certificate delivered pursuant hereto shall survive the execution and delivery of this Agreement, and no investigation by the Administrative Agent or any Lender shall affect the representations and warranties or the right of the Administrative Agent or any Lender to rely upon them.

7.8 Amendments and Waivers. This Agreement and the provisions hereof may not be amended, waived, modified, changed, discharged or terminated except as set forth in Section 11.01 of the Credit Agreement.

7.9 Counterparts. This Agreement may be executed in any number of counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

7.10 Severability. Any provision of this Agreement which is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions of this Agreement, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction.

7.11 Construction. The Pledgors and the Administrative Agent acknowledge that each of them has had the benefit of legal counsel of its own choice and has been afforded an opportunity to review this Agreement with its legal counsel and that this Agreement shall be construed as if jointly drafted by the Pledgors and the Administrative Agent.

7.12 Secured Obligations Absolute. The obligations of the Pledgors under this Agreement shall be absolute and unconditional and shall not be released, discharged, reduced, or in any way impaired by any circumstance whatsoever, including, without limitation, any amendment, modification, extension, or renewal of this Agreement, the Secured Obligations, or any document or instrument evidencing, securing, or otherwise relating to the Secured Obligations, or any release, subordination, or impairment of collateral, or any waiver, consent, extension, indulgence, compromise, settlement, or other action or inaction in respect of this Agreement, the Secured Obligations, or any document or instrument evidencing, securing, or otherwise relating to the Secured Obligations, or any exercise or failure to exercise any right remedy, power, or privilege in respect of the Secured Obligations.

7.13 Termination. On the Collateral Termination Date, the Liens created hereby shall terminate, and the Administrative Agent, at the request and expense of each Pledgor, forthwith will execute and deliver to such Pledgor a proper instrument or instruments acknowledging the satisfaction and termination of the Liens created hereby and will duly assign, transfer and deliver to such Pledgor (without recourse and without any representation or warranty), such of the Collateral as may be in the possession of the Lender and as has not theretofore been sold or otherwise applied pursuant to this Agreement or the Credit Agreement. Upon such release and redelivery, this Agreement shall terminate.

7.14 ENTIRE AGREEMENT. THIS AGREEMENT, TOGETHER WITH THE OTHER LOAN DOCUMENTS, EMBODIES THE FINAL, ENTIRE AGREEMENT AMONG THE PARTIES HERETO AND SUPERSEDES ANY AND ALL PRIOR COMMITMENTS, AGREEMENTS, REPRESENTATIONS, AND UNDERSTANDINGS, WHETHER WRITTEN OR ORAL, RELATING TO THE SUBJECT MATTER HEREOF.

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7.15 Other Security. To the extent that any of the Secured Obligations are now or hereafter secured by Property other than the Collateral or by a guarantee, endorsement or property of any other Person in favor of the Administrative Agent on behalf of the Secured Parties, then the Administrative Agent shall have the right to proceed against such other Property, guarantee or endorsement upon the occurrence and during the continuance of any Event of Default, and the Administrative Agent shall have the right, in its sole discretion, to determine which rights, security, liens, security interests or remedies the Administrative Agent shall at any time pursue, relinquish, subordinate, modify or take with respect thereto, without in any way modifying or affecting any of them or the Secured Obligations or any of the rights of the Administrative Agent or the Secured Parties under this Agreement, under any of the other Loan Documents or under any other document relating to the Secured Obligations.

7.16 Joint and Several Obligations of Pledgors.

(a) Each of the Pledgors is accepting joint and several liability hereunder in consideration of the financial accommodation to be provided by the Secured Parties, for the mutual benefit, directly and indirectly, of each of the Pledgors and in consideration of the undertakings of each of the Pledgors to accept joint and several liability for the obligations of each of them.

(b) Each of the Pledgors jointly and severally hereby irrevocably and unconditionally accepts, not merely as a surety but also as a co-debtor, joint and several liability with the other Pledgors with respect to the payment and performance of all of the Secured Obligations arising under this Agreement, the other Loan Documents and any other documents relating to the Secured Obligations, it being the intention of the parties hereto that all the Secured Obligations shall be the joint and several obligations of each of the Pledgors without preferences or distinction among them.

(c) Notwithstanding any provision to the contrary contained herein, in any other of the Loan Documents or in any other documents relating to the Secured Obligations, the obligations of each Guarantor under the Credit Agreement, the other Loan Documents and the documents relating to the Secured Obligations shall be limited to an aggregate amount equal to the largest amount that would not render such obligations subject to avoidance under Section 548 of the United States Bankruptcy Code or any comparable provisions of any applicable state Law.

(d) Each of the Pledgors agree, among themselves, that the provisions of Section 4.06 of the Credit Agreement apply to any liabilities hereunder.

[Signatures on immediately following page.]

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IN WITNESS WHEREOF, the parties hereto have duly executed this Agreement as of the day and year first written above.

QUANTA SERVICES, INC.

SECOND AMENDED AND RESTATED PLEDGE AGREEMENT

QUANTA SERVICES, INC.

SECOND AMENDED AND RESTATED PLEDGE AGREEMENT

QUANTA SERVICES, INC.

SECOND AMENDED AND RESTATED PLEDGE AGREEMENT

QUANTA SERVICES, INC.

SECOND AMENDED AND RESTATED PLEDGE AGREEMENT

QUANTA SERVICES, INC.

SECOND AMENDED AND RESTATED PLEDGE AGREEMENT

Schedule 2.1(a)

SUBSIDIARIES

SCHEDULE 2.2(a)

Form of Irrevocable Stock Power

FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers to the following shares of capital stock of                         , a                      corporation:

and irrevocably appoints                                                   its agent and attorney-in-fact to transfer all or any part of such capital stock and to take all necessary and appropriate action to effect any such transfer. The agent and attorney-in-fact may substitute and appoint one or more persons to act for him.