FIRST AMENDMENT
 
TO
 
AMENDED AND RESTATED CREDIT AGREEMENT
 
Dated as of August 28, 2008
 
among
 
EV ENERGY PARTNERS, L.P.,
As Parent,
 
EV PROPERTIES, L.P.,
as Borrower,
 
THE GUARANTORS,
 
JPMORGAN CHASE BANK, N.A.
as Administrative Agent,
 
and
 
THE LENDERS PARTY HERETO
 

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FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT
 
THIS FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (this “First
Amendment”) dated as of August 28, 2008, is among EV ENERGY PARTNERS, L.P., a
Delaware limited partnership (the “Parent”); EV PROPERTIES, L.P., a Delaware
limited partnership (the “Borrower”); the undersigned guarantors (the
“Guarantors”, and together with the Parent and the Borrower, the “Obligors”);
each of the lenders party to the Credit Agreement referred to below
(collectively, the “Lenders”); and JPMORGAN CHASE BANK, N.A., as administrative
agent for the Lenders (in such capacity, together with its successors in such
capacity, the “Administrative Agent”).
 
R E C I T A L S
 
A. The Borrower, the Parent, the Agents and the Lenders are parties to that
certain Amended and Restated Credit Agreement dated as of October 1, 2007 (as
amended, the “Credit Agreement”), pursuant to which the Lenders have made
certain credit available to and on behalf of the Borrower.
 
B. The Borrower has requested and the Administrative Agent and the Lenders have
agreed to amend certain provisions of the Credit Agreement.
 
C. NOW, THEREFORE, to induce the Administrative Agent and the Lenders to enter
into this First Amendment and in consideration of the premises and the mutual
covenants herein contained, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:
 
Section 1.  Defined Terms. Each capitalized term used herein but not otherwise
defined herein has the meaning given such term in the Credit Agreement, as
amended by this First Amendment. Unless otherwise indicated, all section
references in this First Amendment refer to sections of the Credit Agreement.
 
Section 2.  Amendments to Credit Agreement.
 
2.1  Amendments to Section 1.02.
 
(a)  The definition of “Agreement” is hereby amended in its entirety to read as
follows:
 
“Agreement” means this Credit Agreement, as amended by the First Amendment,
including the Schedules and Exhibits hereto, as the same may be amended or
supplemented from time to time.
 
(b)  The definition of “Applicable Margin” is hereby amended in its entirety to
read as follows:
 
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“Applicable Margin” means, for any day, with respect to any ABR Loan or
Eurodollar Loan, as the case may be, the rate per annum set forth in the
Borrowing Base Utilization Grid below based upon the Borrowing Base Utilization
Percentage then in effect:
 
Borrowing Base Utilization Grid
Borrowing Base Utilization Percentage
≤ 50%
> 50% ≤ 75%
> 75% ≤ 90%
> 90%
ABR Loans
0.000%
0.000%
0.250%
0.500%
Eurodollar Loans
1.250%
1.500%
1.750%
2.000%

Each change in the Applicable Margin shall apply during the period commencing on
the effective date of such change and ending on the date immediately preceding
the effective date of the next such change, provided, however, that if at any
time the Borrower fails to deliver a Reserve Report pursuant to Section 8.12(a),
then the “Applicable Margin” means the rate per annum set forth on the grid when
the Borrowing Base Utilization Percentage is at its highest level.
 
(c)  The following definitions are hereby added where alphabetically appropriate
to read as follows:
 
“Acquisition” means each of (i) the Protégé Acquisition, (ii) the San Juan
Acquisition and (iii) the Trek Acquisition.
 
“Acquisition Documents” means collectively, (i) the Protégé Acquisition
Documents, (ii) the San Juan Acquisition Documents and (iii) the Trek
Acquisition Documents.
 
“Acquisition Properties” means collectively, (i) the Protégé Acquisition
Properties, (ii) the San Juan Acquisition Properties and (iii) the Trek
Acquisition Properties.
 
“First Amendment” means that certain First Amendment to Amended and Restated
Credit Agreement, dated as of August 28, 2008, among the Parent, the Borrower,
the Guarantors, the Administrative Agent and the Lenders party thereto.
 
“First Amendment Effective Date” means August 28, 2008.
 
“Protégé Acquisition” means the acquisition of certain Oil and Gas Properties
pursuant to the terms and conditions of the Protégé Acquisition Documents.
 
“Protégé Acquisition Documents” means (a) the Purchase and Sale Agreement
between Protégé Energy LLC, as Seller, and Borrower, as Buyer, dated as of July
16, 2008, to be effective as of June 1, 2008, and (b) all bills of sale,
assignments, agreements, instruments and documents executed and delivered in
connection therewith, as amended.
 
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“Protégé Acquisition Properties” means the Oil and Gas Properties and other
properties acquired by the Borrower pursuant to the Protégé Acquisition
Documents.
 
“San Juan Acquisition” means the acquisition of certain Oil and Gas Properties
pursuant to the terms and conditions of the San Juan Acquisition Documents.
 
“San Juan Acquisition Documents” means (a) the Purchase and Sale Agreement
between EnerVest Energy Institutional Fund IX, L.P. and Energy Institutional
Fund IX-WI, L.P., as Sellers, and Borrower, as Buyer, dated as of August 11,
2008, to be effective as of June 1, 2008, and (b) all bills of sale,
assignments, agreements, instruments and documents executed and delivered in
connection therewith, as amended.
 
“San Juan Acquisition Properties” means the Oil and Gas Properties and other
properties acquired by the Borrower pursuant to the San Juan Acquisition
Documents.
 
“Trek Acquisition” means the acquisition of certain Oil and Gas Properties
pursuant to the terms and conditions of the Trek Acquisition Documents.
 
“Trek Acquisition Documents” means (a) the Purchase and Sale Agreement between
Trek Resources, Inc., as Seller, and Borrower, as Buyer, dated July 17, 2008, to
be effective as of August 1, 2008, and (b) all bills of sale, assignments,
agreements, instruments and documents executed and delivered in connection
therewith, as amended.
 
“Trek Acquisition Properties” means the Oil and Gas Properties and other
properties acquired by the Borrower pursuant to the Trek Acquisition Documents.
 
2.2  Amendment to Section 2.07(a). Section 2.07(a) is hereby amended in its
entirety to read as follows:
 
(a) Borrowing Base. For the period from and including the First Amendment
Effective Date to but excluding the next Scheduled Redetermination Date, the
amount of the Borrowing Base shall be $415,000,000. In connection with each
Acquisition, assuming the conditions in Section 6.03 are satisfied with respect
to such Acquisition, the Borrowing Base shall automatically increase by the
amount set forth for such Acquisition on Attachment I to the First Amendment
(the “Acquisition Borrowing Base Adjustment”).
 
2.3  Amendment to Section 3.05(d). Section 3.05(d) is hereby amended in its
entirety to read as follows:
 
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(d) Borrowing Base Increase Fees. The Borrower agrees to pay to the
Administrative Agent, for the account of each Lender then party to this
Agreement, ratably in accordance with its Applicable Percentage, a Borrowing
Base increase fee in an amount to be agreed at such time, on the amount of any
increase of the Borrowing Base over the highest Borrowing Base previously in
effect, payable on the day a New Borrowing Base Notice is given.
 
2.4  Amendment to Section 6.03. Section 6.03 is hereby amended in its entirety
as follows:
 
Section 6.03 Acquisition Borrowing Base Adjustments. Each Acquisition Borrowing
Base Adjustment shall not become effective until the date on which each of the
following conditions is satisfied:

(a) The Acquisition related to such Acquisition Borrowing Base Adjustment closes
on or before October 1, 2008.
 
(b) The Administrative Agent shall have received (i) a certificate of a
Responsible Officer certifying: (A) that the Borrower is concurrently
consummating such Acquisition in accordance with the terms of the relevant
Acquisition Documents (with all of the material conditions precedent thereto
having been satisfied in all material respects by the parties thereto) and
acquiring substantially all of the relevant Acquisition Properties contemplated
by such Acquisition Documents; (B) as to the final purchase price for such
Acquisition Properties after giving effect to all adjustments as of the closing
date contemplated by the relevant Acquisition Documents and specifying, by
category, the amount of such adjustment; (C) that attached thereto is a true and
complete list of the Acquisition Properties which have been excluded from such
Acquisition pursuant to the terms of the Acquisition Documents, specifying with
respect thereto the basis of exclusion as (1) title defect, (2) preferential
purchase right, (3) environmental or (4) casualty loss; (D) that attached
thereto is a true and complete list of all Acquisition Properties for which any
seller has elected to cure a title defect; (E) that attached thereto is a true
and complete list of all Acquisition Properties for which any seller has elected
to remediate an adverse environmental condition; and (F) that attached thereto
is a true and complete list of all Acquisition Properties which are currently
pending final decision by a third party regarding purchase of such property in
accordance with any preferential right; (ii) a true and complete executed copy
of each of the material Acquisition Documents; and (iii) such other related
documents and information as the Administrative Agent shall have reasonably
requested.
 
(c) The Administrative Agent shall have received from the Borrower duly executed
Security Instruments in compliance with Section 8.14(a) and (b), as applicable,
for the relevant Acquisition Properties.
 
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(d) The Administrative Agent shall have received title information as the
Administrative Agent may reasonably require and which is satisfactory to the
Administrative Agent setting forth the status of title to the relevant
Acquisition Properties evaluated in the applicable Reserve Report.
 
(e) The Administrative Agent shall be reasonably satisfied with the
environmental condition of the relevant Acquisition Properties.
 
(f) The Administrative Agent shall have received appropriate UCC search
certificates reflecting no prior Liens encumbering the relevant Acquisition
Properties other than those being released or assigned to Administrative Agent
concurrently with the consummation of such Acquisition and Liens permitted under
Section 9.03.
 
(g) The Administrative Agent shall have received a legal opinion of the
Borrower’s legal counsel in a form and of substance reasonably acceptable to the
Administrative Agent.
 
(h) The Administrative Agent shall have received a certificate of a Responsible
Officer certifying (i) that the Borrower has received all consents and approvals
required by Section 7.03 in connection with such Acquisition and (ii) there are
no actions, suits, investigations or proceedings by or before any arbitrator or
Governmental Authority pending against or, to the knowledge of the Parent or the
Borrower, threatened against or affecting the Parent, the Borrower or any of
their Subsidiaries that involve any relevant Acquisition Document, the
Transactions or that could impair the consummation of the Acquisition on the
time and in the manner contemplated by such Acquisition Documents.
 
(i) The Administrative Agent shall have received evidence satisfactory to it
that all Liens associated with such Acquisition Properties (other than Liens
permitted under Section 9.03) have been released or terminated or assigned to
the Administrative Agent contemporaneously with the Acquisition and that
arrangements satisfactory to the Administrative Agent have been made for
recording and filing of such releases or assignments, as applicable.
 
(j) The Administrative Agent shall have received such other documents as the
Administrative Agent or special counsel to the Administrative Agent may
reasonably request with respect to such Acquisition.
 
2.5  Amendment to Annex I. Annex I is hereby amended in it entirety by
substituting Annex I-A attached hereto.
 
Section 3.  Additional Lenders and Reallocation of Commitments and Loans. The
Borrower has requested an increase in the Aggregate Maximum Credit Amounts
pursuant to Section 2.06(c) of the Credit Agreement to an aggregate maximum
amount of $700,000,000. In lieu of the requirements under Section
2.06(c)(ii)(E), the Lenders have agreed among themselves, in consultation with
the Borrower, to reallocate their respective Commitments. Further, ING Capital
LLC, U.S. Bank National Association and The Frost National Bank shall each
become party to the Credit Agreement as an Additional Lender. On the First
Amendment Effective Date and after giving effect to such reallocation of the
total Commitments, the Commitment of each Lender shall be as set forth on Annex
I-A of this First Amendment. Each Additional Lender shall be deemed to have
acquired the Commitment allocated to it pursuant to the terms of the Additional
Lender Certificate attached as Exhibit E-2 to the Credit Agreement as if such
Additional Lender had executed an Additional Lender Certificate with respect to
such allocation. The Administrative Agent and the Borrower hereby consent to the
reallocation of Commitments and each Additional Lender’s acquisition of an
interest in the total Commitments. Pursuant to the terms hereof, the Borrower is
increasing the Aggregate Maximum Credit Amounts to the maximum allowed under
Section 2.06(c)(ii)(A); therefore, after giving effect to this First Amendment,
Section 2.06(c) of the Credit Agreement shall have no further force or effect.
 
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Section 4.  Conditions Precedent. This First Amendment shall not become
effective until the date on which each of the following conditions is satisfied
(or waived in accordance with Section 12.02 of the Credit Agreement):
 
4.1  The Administrative Agent shall have received from each of the Lenders, the
Additional Lenders, the Parent, the Borrower and the Guarantors, counterparts
(in such number as may be requested by the Administrative Agent) of this First
Amendment signed on behalf of such Person.
 
4.2  The Administrative Agent and the Lenders shall have received all fees and
other amounts due and payable on or prior to the date hereof.
 
4.3  No Default shall have occurred and be continuing as of the date hereof,
after giving effect to the terms of this First Amendment.
 
The Administrative Agent is hereby authorized and directed to declare this First
Amendment to be effective when it has received documents confirming or
certifying, to the satisfaction of the Administrative Agent, compliance with the
conditions set forth in this Section 4 or the waiver of such conditions as
permitted hereby. Such declaration shall be final, conclusive and binding upon
all parties to the Credit Agreement for all purposes.
 
Section 5.  Miscellaneous.
 
5.1  Confirmation. The provisions of the Credit Agreement, as amended by this
First Amendment, shall remain in full force and effect following the
effectiveness of this First Amendment.
 
5.2  Ratification and Affirmation; Representations and Warranties. Each Obligor
hereby (a) acknowledges the terms of this First Amendment; (b) ratifies and
affirms its obligations under, and acknowledges, renews and extends its
continued liability under, each Loan Document to which it is a party and agrees
that each Loan Document to which it is a party remains in full force and effect,
except as expressly amended hereby, notwithstanding the amendments contained
herein and (c) represents and warrants to the Lenders that as of the date
hereof, after giving effect to the terms of this First Amendment: (i) all of the
representations and warranties contained in each Loan Document to which it is a
party are true and correct, except to the extent any such representations and
warranties are expressly limited to an earlier date, in which case, such
representations and warranties shall continue to be true and correct as of such
specified earlier date, (ii) no Default or Event of Default has occurred and is
continuing and (iii) no event or events have occurred which individually or in
the aggregate could reasonably be expected to have a Material Adverse Effect.
 
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5.3  Counterparts. This First Amendment may be executed by one or more of the
parties hereto in any number of separate counterparts, and all of such
counterparts taken together shall be deemed to constitute one and the same
instrument. Delivery of this First Amendment by facsimile transmission shall be
effective as delivery of a manually executed counterpart hereof.
 
5.4  No Oral Agreement. This First Amendment, the Credit Agreement and the other
Loan Documents executed in connection herewith and therewith represent the final
agreement between the parties and may not be contradicted by evidence of prior,
contemporaneous, or unwritten oral agreements of the parties. There are no
subsequent oral agreements between the parties.
 
5.5  GOVERNING LAW. THIS FIRST AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF TEXAS.
 
5.6  Payment of Expenses. In accordance with Section 12.03 of the Credit
Agreement, the Borrower agrees to pay or reimburse the Administrative Agent for
all of its reasonable out-of-pocket costs and reasonable expenses incurred in
connection with this First Amendment, any other documents prepared in connection
herewith and the transactions contemplated hereby, including, without
limitation, the reasonable fees and disbursements of counsel to the
Administrative Agent.
 
5.7  Severability. Any provision of this First Amendment 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 hereof, and any such prohibition or unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any
other jurisdiction.
 
5.8  Successors and Assigns. This Agreement shall be binding upon and inure to
the benefit of the parties hereto and their respective successors and assigns.
 
[SIGNATURES BEGIN NEXT PAGE]
 
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IN WITNESS WHEREOF, the parties hereto have caused this First Amendment to be
duly executed as of the date first written above.
 

      BORROWER:   EV PROPERTIES, L.P.  
   
By:    
EV Properties GP, LLC, its general partner  By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer   Title: Senior Vice President and Chief Financial
Officer

      PARENT AND GUARANTOR:   EV ENERGY PARTNERS, L.P.  
   
By:    
EV Energy GP, L.P., its general partner   By:   EV Management, L.L.C., its
general partner  By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer  
Title: Senior Vice President and Chief Financial Officer

      OTHER GUARANTORS:   EV PROPERTIES GP, LLC  
   
  By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer   Title: Senior Vice President and Chief Financial
Officer

        ENERVEST PRODUCTION PARTNERS, LTD.  
   
By:    
EVPP GP, LLC, its general partner  By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer   Title: Senior Vice President and Chief Financial
Officer

        CGAS PROPERTIES, L.P.  
   
By:  
 EVCG GP, LLC, its general partner By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer   Title: Senior Vice President and Chief Financial
Officer

        ENERVEST-CARGAS, LTD.  
   
By:    
EVPP GP, LLC, its general partner  By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer
 
Title: Senior Vice President and Chief Financial Officer

 
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LOWER CARGAS OPERATING COMPANY
LLC
 
   
By:   
Enervest-Cargas, Ltd., its sole member    By:  Enervest-Cargas, Ltd., its sole
member  By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer
  Title: Senior Vice President and Chief Financial Officer

       
EVPP GP, LLC
EVCG GP, LLC
 
   
   
  By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer
  Title: Senior Vice President and Chief Financial Officer

       
ENERVEST MONROE MARKETING, LTD.
ENERVEST MONROE GATHERING, LTD.
 
   
By:   
EVPP GP, LLC, its general partner By:   /s/ MICHAEL E. MERCER  

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Name: Michael E. Mercer
  Title: Senior Vice President and Chief Financial Officer

      ADMINISTRATIVE AGENT 
JPMORGAN CHASE BANK, N.A., as
Administrative Agent and as a Lender
 
   
    By:   /s/ MICHAEL A. KAMAUF  

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Name: Michael A. Kamauf
 
Title: Vice President 

      LENDERS 
UNION BANK OF CALIFORNIA, N.A.,
as a Lender
 
   
   
  By:   /s/ DANIEL A. DAVIS  

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Name: Daniel A. Davis   
Title: Vice President

       
WACHOVIA BANK, NATIONAL 
ASSOCIATION, as a Lender
 
   
   
  By:   /s/ PAUL PRITCHETT  

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Name: Paul Pritchett   Title: Vice President

 
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        COMPASS BANK, as a Lender  
   
   
  By:   /s/ DOROTHY MARCHAND  

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Name: Dorothy Marchand   Title: Senior Vice President

        BNP PARIBAS, as a Lender  
   
   
  By:   /s/ POLLY SCHOTT  

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Name: Polly Schott   Title: Director

      By:   /s/ BETSY JOCHER  

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Name: Betsy Jocher  
Title: Director

        COMERICA BANK, as a Lender  
   
   
  By:   /s/ MATTHEW TURNER  

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Name: Matthew Turner
  Title: Corporate Banking Officer

        WELLS FARGO BANK, N.A., as a Lender  
   
   
  By:   /s/ SCOTT HODGES  

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Name: Scott Hodges  
Title: Vice President

     
CITIBANK, N.A., as a Lender
 
   
   
  By:   /s/ THOMAS BENAVIDES  

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Name: Thomas Benavides   Title: Senior Vice President

      THE BANK OF NOVA SCOTIA, as a Lender  
   
   
  By:   /s/ ANDY OSTROV  

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Name: Andy Ostrov   Title: Director

      ROYAL BANK OF CANADA, as a Lender  
   
   
  By:   /s/ DON J. MCKINNERNEY  

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Name: Don J. McKinnerney
  Title: Authorized Signatory

     
AMEGY BANK NATIONAL
ASSOCIATION, as a Lender
 
   
   
  By:   /s/ W. BRYAN CHAPMAN  

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Name: W. Bryan Chapman
  Title: Senior Vice President

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CREDIT SUISSE, CAYMAN ISLANDS
BRANCH, as a Lender
 
   
   
  By:   /s/ VANESSA GOMEZ  

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Name: Vanessa Gomez  
Title: Director

    By:   /s/ NUPUR KUMAR  

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Name: Nupur Kumar   Title:  Associate

    ADDITIONAL LENDERS:    ING CAPITAL LLC, as a Lender  
   
   
  By:   /s/ CHARLES HALL  

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Name: Charles Hall
  Title: Managing Director

     
U.S. BANK NATIONAL
ASSOCIATION, as a Lender
 
   
   
  By:   /s/ HEATHER H. HAN  

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Name: Heather H. Han   Title: Vice President

     
THE FROST NATIONAL BANK, as a
Lender
 
   
   
  By:   /s/ ANDREW A MERRYMAN  

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Name: Andrew A. Merryman   Title: Senior Vice President

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ATTACHMENT I
 
Acquisition
Borrowing Base Increase Amount
Protégé Acquistion
 
and
 
Trek Acquisition
 
 
 
30,000,000 (Total Borrowing Base of $445,000,000)
 
San Juan Acquisition
 
 
$80,000,000 (Total Borrowing Base of $525,000,000)

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