EXHIBIT 1.1

                                                                  EXECUTION COPY

                            EV ENERGY PARTNERS, L.P.

                             3,900,000 COMMON UNITS
                     REPRESENTING LIMITED PARTNER INTERESTS

                             UNDERWRITING AGREEMENT

                                                              September 26, 2006

A.G. EDWARDS & SONS, INC.
RAYMOND JAMES & ASSOCIATES, INC.
WACHOVIA CAPITAL MARKETS, LLC
OPPENHEIMER & CO. INC.

c/o A.G. Edwards & Sons, Inc.
One North Jefferson Avenue
St. Louis, Missouri 63103

      The undersigned, EV Energy Partners, L.P., a Delaware limited partnership
(the "Partnership"), EV Energy GP, L.P., a Delaware limited partnership and
general partner of the Partnership (the "General Partner"), EV Management, LLC,
a Delaware limited liability company and general partner of the General Partner
("GP LLC"), EV Properties, L.P., a Delaware limited partnership (the "Operating
Partnership"), EV Properties GP, LLC, a Delaware limited liability company and
general partner of the Operating Partnership (the "Operating Partnership GP"),
EnerVest Management Partners, Ltd., a Texas limited partnership ("EVMP"), CGAS
Exploration, Inc., an Ohio corporation ("CGAS"), EnerVest Operating, LLC, a
Texas limited liability company ("EVOC"), EnCap Energy Capital Fund V, L.P., a
Texas limited partnership ("EnCap Fund V"), EnCap V-B Acquisitions, L.P., a
Texas limited partnership (together with EnCap Fund V, the "EnCap Entities"),
EVEC Holdings, LLC, a Delaware limited liability company ("EVH"), and CGAS
Holdings, LLC, a Delaware limited liability company ("CGH" and together with
EVMP, EVH and the EnCap Entities, the "Sponsor Entities"), hereby address you as
the "Underwriters" and hereby confirm their agreement with the several
Underwriters named below.

      The Partnership, the General Partner, GP LLC, the Operating Partnership
GP, the Operating Partnership, and the Sponsor Entities are collectively
referred to herein as the "EVEP Parties." The Partnership, the General Partner,
GP LLC, the Operating Partnership GP and the Operating Partnership and the other
Subsidiaries (as defined in Section 5(l)) are referred to collectively herein as
the "Partnership Entities."

      It is understood and agreed by all that the Partnership was recently
formed by EVMP and the General Partner to acquire, produce and develop oil and
natural gas properties. The Partnership will initially own oil and natural gas
properties and related gathering systems and production assets in Northern
Louisiana (the "Monroe Assets"), primarily in West Virginia (the



"West Virginia Assets") and primarily in Ohio (the "Clinton Assets"). Currently,
the Operating Partnership indirectly owns all of the interests in the Monroe
Assets through its direct and indirect ownership of EnerVest Production
Partners, L.P. ("EVPP") and its indirect ownership of Lower Cargas Operating
Company LLC ("LCOC") and all of the West Virginia Assets through its direct and
indirect ownership of EnerVest WV, LP ("EVWV"); and CGAS owns all of the Clinton
Assets.

      Prior to the date hereof, the following transactions occurred:

      1.    EVOC formed EVPP GP LLC, a Delaware limited liability company ("EVPP
            GP").

      2.    EVOC contributed its general partner interest in EVPP and its
            general partner interest in EnerVest-Cargas, Ltd., a Texas limited
            partnership ("EV Cargas") to EVPP GP.

      3.    EVMP formed EVWV GP LLC, a Delaware limited liability company ("EVWV
            GP").

      4.    EVMP contributed its general partner interest in EVWV to EVWV GP.

      5.    EVMP, certain members of management, and the EnCap Entities formed
            EV Investors, L.P. ("EV Investors"), a Delaware limited partnership.

      6.    EVMP formed Operating Partnership GP.

      7.    Operating Partnership GP, EVMP, EVOC, the EnCap Entities and EV
            Investors formed the Operating Partnership.

      8.    Operating Partnership GP contributed cash to Operating Partnership
            in exchange for a 0.01% general partner interest in Operating
            Partnership.

      9.    EVMP contributed the membership interest in EVWV GP and its limited
            partner interest in EVPP (subject to debt of $10.3 million incurred
            to purchase the Northern Louisiana properties (the "EVPP Debt")) to
            Operating Partnership in exchange for a 7.71% limited partner
            interest in Operating Partnership

      10.   EVOC contributed its 100% member interest in EVPP GP to Operating
            Partnership in exchange for a 54.03% limited partner interest in
            Operating Partnership.

      11.   The EnCap Entities contributed an aggregate net $16 million to
            Operating Partnership in exchange for an aggregate 33.25% limited
            partner interest in Operating Partnership.

      12.   The Operating Partnership issued a 5.00% Class B limited partner
            interest to EV Investors.

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      13.   The Operating Partnership paid $16 million to Liberty Energy, LLC, a
            Massachusetts limited liability company ("LEC") (and successor to
            Liberty Energy Corporation), in exchange for LEC's limited
            partnership interest in EVWV.

      14.   The Operating Partnership formed EVCG GP LLC ("EVCG GP"), a Delaware
            limited liability company.

      15.   EVCG GP, as general partner, and CGAS, as limited partner, formed
            CGAS Properties, L.P. ("Clinton Properties"), a Delaware limited
            partnership.

      16.   EVMP formed GP LLC.

      17.   GP LLC, as general partner, and EVMP, as limited partner, formed the
            General Partner.

      18.   The General Partner, as general partner, and EVMP, as limited
            partner, formed the Partnership.

      The transactions described in clauses (1)-(18) above are referred to
herein collectively as the "Prior Transactions."

      It is further understood and agreed to by all parties that, on or prior to
the Closing Date, the following transactions will occur:

      1.    CGAS has formed CGH and assigned to it the right to receive the
            Common Units and Subordinated Units that CGAS is entitled to receive
            from the Partnership as described herein.

      2.    EVMP formed EVH and assigned to it the right to receive the Common
            Units and Subordinated Units that EVMP and EVOC are entitled to
            receive from the Partnership as described herein.

      3.    CGAS will contribute the Clinton Assets subject to existing hedges
            to Clinton Properties and following such transfer will own a 99.99%
            interest as limited partner in Clinton Properties.

      4.    GP LLC will pay $288.30 to the General Partner to retain its a 0.01%
            general partner interest in the General Partner.

      5.    EVMP will contribute its 100% member interest in the Operating
            Partnership GP and a portion (3.44%) of its limited partner interest
            in the Operating Partnership to the General Partner in exchange for
            a 71.24% limited partner interest in the General Partner.

      6.    The EnCap Entities will contribute a portion (1.18%) of their
            aggregate limited partner interest in the Operating Partnership to
            the General Partner in exchange for an aggregate 23.75% limited
            partner interest in the General Partner.

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      7.    EV Investors will contribute $144,150.00 to the General Partner for
            a 5.00% limited partnership interest in the General Partner.

      8.    The General Partner will contribute its 100% member interest in the
            Operating Partnership GP, its 4.63% limited partner interests in the
            Operating Partnership to the Partnership and $144,150.00 in exchange
            for (a) a 2% general partner interest in the Partnership and (b) the
            Incentive Distribution Rights (as defined in Section 1.1 of the
            Partnership Agreement).

      9.    EVOC will contribute its 58.30% limited partner interest in the
            Operating Partnership to the Partnership in exchange for (a) 138,381
            Common Units (as defined in Section 1.1 of the Partnership
            Agreement) representing limited partner interests in the Partnership
            to be issued to EVH, (b) 810,030 Subordinated Units (as defined in
            Section 1.1 of the Partnership Agreement) representing limited
            partner interests in the Partnership to be issued to EVH, and (c)
            the right to receive $14,519,564.03 from the Offering Proceeds (as
            defined below).

      10.   EVMP will contribute the remainder (4.27%) of its limited partner
            interest in the Operating Partnership to the Partnership in exchange
            for (a) 25,244 Subordinated Units representing limited partner
            interests in the Partnership to be issued to EVH, and (b) the right
            to receive $2,072,327.22 from the Offering Proceeds.

      11.   The EnCap Entities will contribute the remainder (32.07%) of their
            limited partner interest in the Operating Partnership to the
            Partnership in exchange for (a) 88,120 Common Units representing
            limited partner interests in the Partnership, (b) 436,170
            Subordinated Units representing limited partner interests in the
            Partnership, and (c) the right to receive $8,935,488 from the
            Offering Proceeds.

      12.   EV Investors will contribute its 5.00% limited partner interest in
            the Operating Partnership to the Partnership in exchange for 155,000
            Subordinated Units representing limited partner interests in the
            Partnership.

      13.   CGAS will transfer its limited partner interest in EVCG to the
            Partnership in exchange for (a) 343,255 Common Units representing
            limited partner interests in the Partnership to be issued to CGH,
            (b) 1,698,800 Subordinated Units representing limited partner
            interests in the Partnership to be issued to CGH, and (c) the right
            to receive $34,806,771.14 from the Offering Proceeds.

      14.   The public, through the underwriters, will contribute $72.54 million
            in cash, $78.0 million of gross proceeds, net of the Underwriters'
            discounts and commissions and a structuring fee (the "Offering
            Proceeds"), to the Partnership in exchange for 3.9 million Common
            Units representing a 50.3% limited partner interest in the
            Partnership (the "Offering").

      15.   The Partnership will use the Offering Proceeds and the cash
            contribution from the General Partner to (i) pay the underwriters'
            structuring fee, (ii) pay approximately $2.0 million in offering
            expenses (net of the Underwriters' discounts and commissions and
            structuring fees) incurred by EVMP on behalf of the

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            Partnership, (iii) contribute $10.35 million to the Operating
            Partnership, and the Operating Partnership will repay the EVPP Debt
            and (iv) distribute to EVMP, EVOC, EV Investors, the EnCap Entities
            and CGAS a total of $60.33 million in the amounts to which they are
            entitled with respect to each entity's respective contribution to
            the Partnership.

      16.   The Partnership will contribute the limited partner interest in EVCG
            to the Operating Partnership as a capital contribution.

      17.   The Operating Partnership will enter into $150 million revolving
            credit facility with JP Morgan Securities Inc., as administrative
            agent, and the other lenders named therein (collectively with the
            other financing documents entered into in connection therewith, the
            "Credit Facility").

      18.   The agreements of limited partnership and the limited liability
            company agreements of the aforementioned entities will be amended
            and restated to the extent necessary to reflect the foregoing
            transactions and any other transactions contemplated by the
            Contribution Documents (as defined below).

      19.   If the Underwriters exercise their option to purchase any Option
            Units within 30 days after the date of this Agreement as provided in
            Section 4, the Partnership will use the net proceeds of the sale of
            those Option Units to redeem a pro rata portion of the Common Units
            issued to EVMP, EVOC, CGAS, and the EnCap Entities.

      The transactions described above in clauses (l)-(19) or otherwise provided
for in the Contribution Documents (as defined below) together with the Prior
Transactions, are referred to as the "Transactions." In connection with the
Transactions, the parties to the Transactions have entered or will enter into
various bills of sale, assignments, conveyances, contribution agreements and
related documents (collectively, the "Contribution Documents"). The Omnibus
Agreement to be dated the Closing Date among the Partnership, the General
Partner, the GP LLC, the Operating Partnership and EVMP is referred to herein as
the "Omnibus Agreement." The Investor Rights Agreement to be dated the Closing
Date among EVMP, EVOC, EV Investors, CGAS, the EnCap Entities and EV Management,
L.P. is referred to herein as the "Investor Agreement." The Contribution
Documents, the Credit Facility, the Omnibus Agreement and the Investor Agreement
are referred to herein collectively as the "Transaction Documents."

      1.    DEFINITIONS. As used in this Agreement:

                  (i) "Disclosure Package" shall mean the Statutory Prospectus,
            any Preliminary Prospectus together with any combination of one or
            more of the Permitted Free Writing Prospectuses, if any, and any
            other free writing prospectus that the parties hereto shall
            hereafter expressly agree in writing to treat as part of the
            Disclosure Package.

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                  (ii) "Effective Date" shall mean each date and time that the
            Registration Statement, any post-effective amendment or amendments
            thereto and any Rule 462(b) Registration Statement became or become
            effective.

                  (iii) "Execution Time" shall mean the date and time (3:10
            p.m., Central Daylight Time) that this Agreement is executed and
            delivered by the parties hereto.

                  (iv) "Issuer Free Writing Prospectus" shall mean an issuer
            free writing prospectus, as defined in Rule 433.

                  (v) "Permitted Free Writing Prospectus" shall mean the
            documents listed on Schedule III attached hereto, each "road show"
            (as defined in Rule 433(h)(4) under the Act), if any, related to the
            Offering contemplated hereby that is a "written communication" (as
            defined in Rule 405 under the Act) (each such road show, a "Road
            Show") and any other "free writing prospectus" (as defined in Rule
            405 under the Act) to which the Underwriters and the Partnership
            provide their prior consent.

                  (vi) "Preliminary Prospectus" shall mean any preliminary
            prospectus referred to in paragraph 5(a) below and any preliminary
            prospectus included in the Registration Statement at the Effective
            Date that omits Rule 430A Information.

                  (vii) "Prospectus" shall mean the prospectus relating to the
            Units that is first filed pursuant to Rule 424(b) after the
            Execution Time.

                  (viii) "Registration Statement" shall mean the registration
            statement referred to in paragraph 5(a) below, including exhibits
            and financial statements and any prospectus supplement relating to
            the Units that is filed with the SEC pursuant to Rule 424(b) and
            deemed part of such registration statement pursuant to Rule 430A, as
            amended at the Execution Time and, in the event any post-effective
            amendment thereto or any Rule 462(b) Registration Statement becomes
            effective prior to the Closing Date, shall also mean such
            registration statement as so amended or such Rule 462(b)
            Registration Statement, as the case may be.

                  (ix) "Rule 462(b) Registration Statement" shall mean a
            registration statement and any amendments thereto filed pursuant to
            Rule 462(b) relating to the offering covered by the registration
            statement referred to in Section 5(a) hereof.

                  (x) "Statutory Prospectus" shall mean the preliminary
            prospectus relating to the Units that is included in the
            registration statement relating to the Units immediately prior to
            the Execution Time, including any document that is incorporated by
            reference therein.

      2. DESCRIPTION OF COMMON UNITS. The Partnership proposes to issue and sell
to the Underwriters 3,900,000 Common Units (the "Firm Units"). Solely for the
purpose of covering

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over-allotments in the sale of the Firm Units, the Partnership further proposes
to grant to the Underwriters the right to purchase up to an additional 585,000
Common Units (the "Option Units"), as provided in Section 4 of this Agreement.
The Firm Units and the Option Units are herein sometimes referred to as the
"Units" and are more fully described in the Prospectus hereinafter defined.

      3. PURCHASE, SALE AND DELIVERY OF THE FIRM UNITS. On the basis of the
representations, warranties and agreements herein contained, but subject to the
terms and conditions herein set forth, the Partnership agrees to sell to the
Underwriters, and each such Underwriter agrees, severally and not jointly, (a)
to purchase from the Partnership, at a purchase price of $18.70 per unit, the
number of Firm Units set forth opposite the name of such Underwriter in Schedule
I hereto and (b) to purchase from the Partnership any additional number of
Option Units which such Underwriter may become obligated to purchase pursuant to
Section 4 hereof.

      Delivery of the Firm Units will be in book-entry form through the
facilities of The Depository Trust Company, New York, New York ("DTC"). Delivery
of the documents required by Section 7 hereof with respect to the Units shall be
made at or prior to 11:00 a.m. on September 29, 2006 at the offices of Haynes
and Boone, LLP, 1221 McKinney, Suite 2100, Houston, Texas 77010 or at such other
place as may be agreed upon between A.G. Edwards & Sons, Inc. and the
Partnership (the "Place of Closing"), or at such other time and date not later
than five full business days thereafter as A.G. Edwards & Sons, Inc. and the
Partnership may agree, such time and date of payment and delivery being herein
called the "Closing Date."

      The Partnership will cause its transfer agent to deposit as original issue
the Firm Units pursuant to the Full Fast Delivery Program of the DTC.

      It is understood that an Underwriter, individually, may (but shall not be
obligated to) make payment on behalf of the other Underwriters whose funds shall
not have been received prior to the Closing Date for Units to be purchased by
such Underwriter. Any such payment by an Underwriter shall not relieve the other
Underwriters of any of their obligations hereunder.

      It is understood that the Underwriters propose to offer the Units to the
public upon the terms and conditions set forth in the Registration Statement
hereinafter defined.

      4. PURCHASE, SALE AND DELIVERY OF THE OPTION UNITS. The Partnership hereby
grants an option to the Underwriters to purchase from the Partnership up to
585,000 Option Units, on the same terms and conditions as the Firm Units;
provided, however, that such option may be exercised only for the purpose of
covering any over-allotments that may be made by the Underwriters in the sale of
the Firm Units. No Option Units shall be sold or delivered unless the Firm Units
previously have been, or simultaneously are, sold and delivered.

      The option is exercisable by the Underwriters at any time, and from time
to time, before the expiration of 30 days from the date of the Prospectus (or,
if such 30th day shall be a Saturday or Sunday or a holiday, on the next day
thereunder when the NASDAQ Global Market is open for trading), for the purchase
of all or part of the Option Units covered thereby, by notice given by A.G.
Edwards & Sons, Inc. to the Partnership in the manner provided in Section 13
hereof,

                                       7


setting forth the number of Option Units as to which the Underwriters are
exercising the option, and the date of delivery of said option Units, which date
shall not be more than five business days after such notice unless otherwise
agreed to by the Partnership and A.G. Edwards & Sons, Inc. The Underwriters may
terminate the option at any time, as to any unexercised portion thereof, by
giving written notice from A.G. Edwards & Sons, Inc. to the Partnership to such
effect.

      The Underwriters shall make such allocation of the Option Units among them
as may be required to eliminate purchases of fractional Units.

      Delivery of the Option Units will be in book-entry form through the
facilities of DTC. Delivery of the documents required by Section 7 hereof with
respect to the Units shall be made at the Place of Closing at or prior to 11:00
a.m. on the date designated in the notice given by A.G. Edwards & Sons, Inc. as
provided above, or at such other time and date as A.G. Edwards & Sons, Inc. and
the Partnership may agree (which may be the same as the Closing Date), such time
and date of payment and delivery being herein called the "Option Closing Date."
On the Option Closing Date, the Partnership Entities and EVMP shall provide the
Underwriters such representations, warranties, agreements, opinions, letters,
certificates and covenants with respect to the Option Units as are required to
be delivered on the Closing Date with respect to the Firm Units.

      The Partnership will cause its transfer agent to deposit as original issue
the Option Units pursuant to the Full Fast Delivery Program of the DTC.

      5. REPRESENTATIONS, WARRANTIES AND AGREEMENTS OF THE EVEP PARTIES. The
EVEP Parties jointly and severally represent and warrant to and agree with each
Underwriter as set forth below; provided, however that the representations and
warranties of the EnCap Entities shall be several, as to themselves only, and
shall be limited to only Sections 5(a), (f), (h) and (q), each with respect
solely to statements and information specifically concerning and the EnCap
Entities or their ownership of Sponsor Units (as defined in Section 5(f):

            (a) Registration; No Material Misstatements or Omissions. The
      Registration Statement has heretofore become effective under the Act or,
      with respect to any registration statement to be filed to register the
      offer and sale of Units pursuant to Rule 462(b) under the Act, will be
      filed with the Commission and become effective under the Act no later than
      10:00 P.M., New York City time, on the date of determination of the public
      offering price for the Units; no stop order of the Commission preventing
      or suspending the use of any Preliminary Prospectus, the Prospectus or any
      Permitted Free Writing Prospectus or the effectiveness of the Registration
      Statement, has been issued, and no proceedings for such purpose have been
      instituted or, to the Partnership's knowledge after due inquiry, are
      contemplated by the Commission; the Registration Statement complied when
      it became effective, complies as of the date hereof and, as amended or
      supplemented, at the time of purchase, each additional time of purchase,
      if any, and at all times during which a prospectus is required by the Act
      to be delivered (whether physically or through compliance with Rule 172
      under the Act or any similar rule) in connection with any sale of Units,
      will comply, in all material respects, with the requirements of the Act;
      the Exchange Act Registration Statement on Form 8-A has

                                       8


      become effective as provided in Section 12 of the Exchange Act; the
      Registration Statement did not, as of the Effective Date, contain an
      untrue statement of a material fact or omit to state a material fact
      required to be stated therein or necessary to make the statements therein
      not misleading; each Preliminary Prospectus complied, at the time it was
      filed with the Commission, and complies as of the date hereof, in all
      material respects with the requirements of the Act; at no time during the
      period that begins on the earlier of the date of such Preliminary
      Prospectus and the date such Preliminary Prospectus was filed with the
      Commission and ends at the time of purchase did or will any Preliminary
      Prospectus, as then amended or supplemented, include an untrue statement
      of a material fact or omit to state a material fact necessary in order to
      make the statements therein, in the light of the circumstances under which
      they were made, not misleading, and at no time during such period did or
      will any Preliminary Prospectus, as then amended or supplemented, together
      with any combination of one or more of the then-issued Permitted Free
      Writing Prospectuses, if any, include an untrue statement of a material
      fact or omit to state a material fact necessary in order to make the
      statements therein, in the light of the circumstances under which they
      were made, not misleading; the Prospectus will comply, as of its date and
      the date it is filed with the Commission, the time of purchase, each
      additional time of purchase, if any, and at all times during which a
      prospectus is required by the Act to be delivered (whether physically or
      through compliance with Rule 172 under the Act or any similar rule) in
      connection with any sale of Units, will comply, in all material respects,
      with the requirements of the Act (including, without limitation, Section
      10(a) of the Act); at no time during the period that begins on the earlier
      of the date of such Prospectus and the date the Prospectus is filed with
      the Commission and ends at the later of the time of purchase, the latest
      additional time of purchase, if any, and the end of the period during
      which a prospectus is required by the Act to be delivered (whether
      physically or through compliance with Rule 172 under the Act or any
      similar rule) in connection with any sale of Units did or will the
      Prospectus, as then amended or supplemented, include an untrue statement
      of a material fact or omit to state a material fact necessary in order to
      make the statements therein, in the light of the circumstances under which
      they were made, not misleading; at no time during the period that begins
      on the date of each such Permitted Free Writing Prospectus and ends at the
      time of purchase did or will any such Permitted Free Writing Prospectus
      include an untrue statement of a material fact or omit to state a material
      fact necessary in order to make the statements therein, in the light of
      the circumstances under which they were made, not misleading, or conflict
      with the information contained in the Registration Statement, the
      Preliminary Prospectus or the Prospectus; provided, however, that the EVEP
      Parties make no representation or warranty in this Section 5(a) with
      respect to any statement contained in the Registration Statement, any
      Preliminary Prospectus, the Prospectus or any Permitted Free Writing
      Prospectus in reliance upon and in conformity with information concerning
      an Underwriter and furnished in writing by or on behalf of such
      Underwriter through you to the Partnership expressly for use in the
      Registration Statement, such Preliminary Prospectus, the Prospectus or
      such Permitted Free Writing Prospectus. If required, all Permitted Free
      Writing Prospectuses were preceded by, or accompanied with, a statutory
      prospectus meeting the requirements of Section 10(a) of the Act as
      required by Rule 164 under the Act.

                                       9


            (b) Prospectuses Used in Offering. Prior to the execution of this
      Agreement, the Partnership has not, directly or indirectly, offered or
      sold any Units by means of any "prospectus" (within the meaning of the
      Act) or used any "prospectus" (within the meaning of the Act) in
      connection with the offer or sale of the Units, in each case other than
      the Preliminary Prospectuses and the Permitted Free Writing Prospectuses,
      if any; the Partnership has not, directly or indirectly, prepared, used or
      referred to any Permitted Free Writing Prospectus except in compliance
      with Rules 164 and 433 under the Act; assuming that such Permitted Free
      Writing Prospectus is so sent or given after the Registration Statement
      was filed with the Commission (and after such Permitted Free Writing
      Prospectus was, if required pursuant to Rule 433(d) under the Act, filed
      with the Commission), the sending or giving, by any Underwriter, of any
      Permitted Free Writing Prospectus will satisfy the provisions of Rule 164
      and Rule 433 (without reliance on subsections (b), (c) and (d) of Rule
      164); each of the Preliminary Prospectuses is a prospectus that, other
      than by reason of Rule 433 under the Act, satisfies the requirements of
      Section 10 of the Act, including a price range where required by rule;
      neither the Partnership nor the Underwriters are disqualified, by reason
      of subsection (f) or (g) of Rule 164 under the Act, from using, in
      connection with the offer and sale of the Units, "free writing
      prospectuses" (as defined in Rule 405 under the Act) pursuant to Rules 164
      and 433 under the Act; the Partnership is not an "ineligible issuer" (as
      defined in Rule 405 under the Act) as of the eligibility determination
      date for purposes of Rules 164 and 433 under the Act with respect to the
      Offering contemplated by the Registration Statement; the parties hereto
      agree and understand that the content of any and all "road shows" (as
      defined in Rule 433(h) under the Act) related to the Offering is solely
      the property of the Partnership; the Partnership has caused there to be
      made available at least one version of a "bona fide electronic road show"
      (as defined in Rule 433(h)(5) under the Act) in a manner that, pursuant to
      Rule 433(d)(8)(ii) under the Act, causes the Partnership not to be
      required, pursuant to Rule 433(d) under the Act, to file with the
      Commission any road show.

            (c) Other Sales. The Partnership has not sold or issued any Units
      during the six-month period preceding the date of the Preliminary
      Prospectus, other than pursuant to acquisitions, employee benefit plans,
      qualified options plans or other employee compensation plans or pursuant
      to outstanding options, rights or warrants described in the Disclosure
      Package and the Prospectus.

            (d) Formation and Due Qualification. Formation and Due
      Qualification. Each of the Partnership Entities has been duly formed or
      incorporated and is validly existing as a limited partnership or limited
      liability company, as the case may be, in good standing under the laws of
      its respective jurisdiction of formation or incorporation, and is, or at
      the Closing Date will be, duly registered or qualified to do business and
      is in good standing as a foreign limited partnership or foreign limited
      liability company, as the case may be, in each jurisdiction in which its
      ownership or lease of property or the conduct of its businesses requires
      such registration or qualification, except where the failure so to
      register or qualify would not (i) have a material adverse effect on the
      consolidated financial position, partners' or members' equity, results of
      operations, business or prospects of the Partnership Entities taken as a
      whole (a "Material Adverse Effect") or (ii) subject the limited partners
      of the Partnership to any material liability or disability, as

                                       10


      set forth under its name on Schedule II to this Agreement. Each of the
      Partnership Entities has all limited partnership or limited liability
      company, as the case may be, power and authority necessary to own or lease
      its properties currently owned or leased or to be owned or leased at the
      Closing Date, to assume the liabilities assumed or being assumed by it
      pursuant to the Transaction Documents and to conduct its business as
      currently conducted and as to be conducted at the Closing Date, in each
      case in all material respects as described in the Prospectus.

            (e) Ownership of the General Partner Interest in the Partnership. At
      the Closing Date and the Option Closing Date, after giving effect to the
      Transactions, the General Partner will be the sole general partner of the
      Partnership with a 2% general partner interest in the Partnership. Such
      general partner interest will be duly authorized and validly issued in
      accordance with the partnership agreement of the Partnership (as the same
      may be amended or restated at or prior to the Closing Date, the
      "Partnership Agreement") and will be fully paid (to the extent required
      under the Partnership Agreement) and nonassessable (except as such
      nonassessability may be affected by Section 17-303 and 17-607 of the
      Delaware Revised Uniform Limited Partnership Act (the "Delaware LP Act")),
      and the General Partner will own such general partner interest free and
      clear of all liens, encumbrances (except restrictions on transferability
      described in the Prospectus), security interests, equities, charges or
      claims.

            (f) Ownership of Sponsor Units and the Incentive Distribution
      Rights. Assuming no purchase by the Underwriters of any Option Units on
      the Closing Date, at the Closing Date, after giving effect to the
      Transactions, (i) EVH will own 163,625 Common Units and 810,030
      Subordinated Units, (ii) EV Investors will own 155,000 Subordinated Units,
      (iii) CGH will own 343,255 Common Units and 1,698,800 Subordinated Units,
      (iv) the EnCap Entities will own 88,120 Common Units and 436,170
      Subordinated Units (all such Common Units and Subordinated Units being
      collectively referred to herein as the "Sponsor Units") as described in
      the Prospectus and (v) the General Partner will own all of the incentive
      distribution rights in the Partnership (as defined in the Partnership
      Agreement, the "Incentive Distribution Rights"); all of such Sponsor Units
      and Incentive Distribution Rights and the limited partner interests
      represented thereby will be duly authorized and validly issued in
      accordance with the Partnership Agreement, and will be fully paid (to the
      extent required under the Partnership Agreement) and nonassessable (except
      as such nonassessability may be affected by Sections 17-303 and 17-607 of
      the Delaware LP Act and as otherwise described in the Prospectus under the
      caption "The Partnership Agreement--Limited Liability," "Risk
      Factors--Risks Inherent in an Investment in Us--Your liability may not be
      limited if a court finds that unitholder action constitutes control of our
      business" and "Risk Factors--Risks Inherent in an Investment in
      Us--Unitholders may have liability to repay distributions that were
      wrongfully distributed to them"); and at the Closing Date, EVMP, EV
      Investors, CGAS and the EnCap Entities will own their respective Sponsor
      Units and the General Partner will own the Incentive Distribution Rights
      free and clear of all liens, encumbrances (except restrictions on
      transferability as described in the Prospectus), security interests,
      equities, charges or claims.

                                       11


            (g) Valid Issuance of the Units. At the Closing Date or the Option
      Closing Date, as the case may be, the Firm Units or the Option Units, as
      the case may be, and the limited partner interests represented thereby,
      will be duly authorized by the Partnership Agreement and, when issued and
      delivered to the Underwriters against payment therefor in accordance with
      the terms hereof will be validly issued, fully paid (to the extent
      required under the Partnership Agreement) and nonassessable (except as
      such nonassessability may be affected by Sections 17-303 and 17-607 of the
      Delaware LP Act and as otherwise described in the Prospectus under the
      caption "The Partnership Agreement--Limited Liability," "Risk
      Factors--Risks Inherent in an Investment in Us--Your liability may not be
      limited if a court finds that unitholder action constitutes control of our
      business" and "Risk Factors--Risks Inherent in an Investment in
      Us--Unitholders may have liability to repay distributions that were
      wrongfully distributed to them"); and other than the Sponsor Units and the
      Incentive Distribution Rights, the Units will be the only limited partner
      interests of the Partnership issued and outstanding at the Closing Date or
      the Option Closing Date.

            (h) Ownership of Partnership Interests in the General Partner. At
      the Closing Date and the Option Closing Date, after giving effect to the
      Transactions, GP LLC will own 100% of the outstanding general partner
      interests in the General Partner and EVMP, Encap Entities and EV Investors
      will own 100% of the outstanding limited partner interests in the General
      Partner; all of such interests will be duly authorized and validly issued
      in accordance with the limited partnership agreement of the General
      Partner (as the same may be amended or restated at or prior to the Closing
      Date, the "General Partner Partnership Agreement")) and will be fully paid
      (to the extent required under the General Partner LP Agreement) and
      nonassessable (except as such nonassessability may be affected by Section
      17-303 and 17-607 of the Delaware LP Act), and at the Closing Date, GP
      LLC, EVMP, the EnCap Entities and EV Investors will own such interests
      free and clear of all liens, encumbrances (except as described in the
      Prospectus), security interests, equities, charges or claims.

            (i) Ownership of Limited Liability Company Interests in the GP LLC.
      At the Closing Date and the Option Closing Date, after giving effect to
      the Transactions, EVMP will own 100% of the outstanding limited liability
      company interests in GP LLC; all of such interests will be duly authorized
      and validly issued in accordance with the limited liability company
      agreement of the GP LLC (as the same may be amended or restated at or
      prior to the Closing Date, the "GP LLC LLC Agreement"). All of such
      interests will be duly authorized and validly issued in accordance with
      the GP LLC LLC Agreement, fully paid (to the extent required under the GP
      LLC LLC Agreement) and nonassessable (except as such nonassessability may
      be affected by Section 18-607 of the Delaware Limited Liability Company
      Act (the "Delaware LLC Act")), and EVMP will own such interests free and
      clear of all liens, encumbrances (except as described in the Prospectus),
      security interests, equities, charges or claims.

            (j) Ownership of Partnership Interests in the Operating Partnership.
      At the Closing Date and the Option Closing Date, after giving effect to
      the Transactions, Operating Partnership GP will own 100% of the
      outstanding general partner interests in the Operating Partnership and the
      Partnership will own 100% of the outstanding limited

                                       12


      partner interests in the Operating Partnership; all of such interests will
      be duly authorized and validly issued in accordance with the limited
      partnership agreement of the Operating Partnership (as the same may be
      amended or restated at or prior to the Closing Date, the "Operating
      Partnership LP Agreement")) and will be fully paid (to the extent required
      under the Operating Partnership LP Agreement) and nonassessable (except as
      such nonassessability may be affected by Section 17-303 and 17-607 of the
      Delaware LP Act), and Operating Partnership GP and the Partnership will
      own such interests free and clear of all liens, encumbrances (except as
      described in the Prospectus), security interests, equities, charges or
      claims.

            (k) Ownership of Limited Liability Company Interests in the
      Operating Partnership GP. At the Closing Date and the Option Closing Date,
      after giving effect to the Transactions, the Partnership will own 100% of
      the outstanding limited liability company interests in Operating
      Partnership GP; all of such interests will be duly authorized and validly
      issued in accordance with the limited liability company agreement of the
      Operating Partnership GP (as the same may be amended or restated at or
      prior to the Closing Date, the "Operating Partnership GP LLC Agreement"),
      and will be fully paid (to the extent required under the Operating
      Partnership GP LLC Agreement) and nonassessable (except as such
      nonassessability may be affected by Section 18-607 of the Delaware LLC
      Act), and the Partnership will own such interests free and clear of all
      liens, encumbrances, security interests, equities, charges or claims.

            (l) Ownership of the Subsidiaries. At the Closing Date and the
      Option Closing Date, after giving effect to the Transactions, the
      Partnership will, directly or indirectly, own 100% of the limited
      liability company interests or partnership interests, as the case may be,
      in EVPP GP LLC, EVWV GP LLC, EVCG GP LLC, EVPP, EVWV, Clinton Properties,
      EV Cargas and LCOC (the "Subsidiaries," together with the Operating
      Partnership and the Operating Partnership GP, the "Operating
      Subsidiaries") free and clear of all liens, encumbrances, security
      interests, equities, charges and other claims, except for liens created
      pursuant to the Credit Facility. At the Closing Date and the Option
      Closing Date, such limited liability company interests or partnership
      interests, as the case may be, will be duly authorized and validly issued
      in accordance with the limited liability company or limited partnership
      agreements, as the case may be, of the respective Subsidiaries, and will
      be fully paid (to the extent required under their respective limited
      liability company agreement or limited partnership agreement) and
      non-assessable (except as such nonassessability may be affected by Section
      18-607 of the Delaware LLC Act, in the case of a Delaware limited
      liability company, or Section 17-607 of the Delaware LP Act, in the case
      of a Delaware limited partnership).

            (m) No Other Subsidiaries. Other than ownership interests in the
      Operating Subsidiaries, the Partnership does not own, and at the Closing
      Date and the Option Closing Date, will not own, directly or indirectly,
      any equity or long-term debt securities of any corporation, partnership,
      limited liability company, joint venture, association or other entity.
      Other than its ownership of its partnership interests in the Partnership,
      the General Partner does not own, and at the Closing Date and the Option
      Closing Date will not own, directly or indirectly, any equity or long-term
      debt securities of any corporation, partnership, limited liability
      company, joint venture, association or other entity.

                                       13


            (n) No Preemptive Rights, Registration Rights or Options. Except as
      described in the Disclosure Package and the Prospectus, there are no
      options, warrants, preemptive rights or other rights to subscribe for or
      to purchase, nor any restriction upon the voting or transfer of, any
      partnership or limited liability company interests in any Partnership
      Entity. Neither the filing of the Registration Statement nor the offering
      or sale of the Units as contemplated by this Agreement gives rise to any
      rights for or relating to the registration of any Units or other
      securities of any of the Partnership Entities.

            (o) Authority and Authorization. The Partnership has all requisite
      power and authority to issue, sell and deliver (i) the Units, in
      accordance with and upon the terms and conditions set forth in this
      Agreement, the Partnership Agreement and the Registration Statement, the
      Disclosure Package and the Prospectus and (ii) the Sponsor Units and
      Incentive Distribution Rights, in accordance with and upon the terms and
      conditions set forth in the Partnership Agreement and the Transaction
      Documents. At the Closing Date and the Option Closing Date, all corporate,
      partnership and limited liability company action, as the case may be,
      required to be taken by the Partnership Entities or any of their
      stockholders, members or partners for the authorization, issuance, sale
      and delivery of the Units, the Sponsor Units and Incentive Distribution
      Rights, the execution and delivery of the Operative Agreements (as defined
      in Section 4(q)) and the consummation of the transactions (including the
      Transactions) contemplated by this Agreement and the Operative Agreements,
      shall have been validly taken.

            (p) Authorization of Underwriting Agreement. This Agreement has been
      duly authorized and validly executed and delivered by each of the EVEP
      Parties.

            (q) Enforceability of Other Agreements. At or before the Closing
      Date:

                  (i) the Partnership Agreement (in substantially the form
            included in the Prospectus) will have been duly authorized, executed
            and delivered by the General Partner and the Sponsor Entities and
            will be a valid and legally binding agreement of the General Partner
            and the Sponsor Entities enforceable against each of them in
            accordance with its terms;

                  (ii) the General Partner Partnership Agreement, GP LLC LLC
            Agreement, Operating Partnership LP Agreement, Operating Partnership
            GP LLC Agreement and the limited liability company agreement or
            limited partnership agreement, as applicable, of each of the
            Subsidiaries (together with the Partnership Agreement (as described
            above), the "Partnership Entity Operative Agreements") will have
            been duly authorized, executed and delivered by the parties thereto
            and will be valid and legally binding agreements of the parties
            thereto, enforceable against such parties in accordance with their
            respective terms; and

                  (iii) each of the Transaction Documents will have been duly
            authorized, executed and delivered by the parties thereto and will
            be valid and legally binding agreements of the parties thereto,
            enforceable against such parties in accordance with their respective
            terms;

                                       14


      provided that, with respect to each agreement described in this Section
      5(q), the enforceability thereof may be limited by (i) bankruptcy,
      insolvency, fraudulent transfer, reorganization, moratorium and similar
      laws relating to or affecting creditors' rights generally and by general
      principles of equity (regardless of whether such enforceability is
      considered in a proceeding in equity or at law) and (ii) public policy,
      applicable law relating to fiduciary duties and indemnification and an
      implied covenant of good faith and fair dealing. The Partnership Entity
      Operative Agreements and the Transaction Documents are herein collectively
      referred to as the "Operative Agreements."

            (r) No Conflicts. None of the offering, issuance and sale by the
      Partnership of the Units, the execution, delivery and performance of this
      Agreement or the Operative Agreements by the Partnership Entities which
      are parties hereto or thereto, or the consummation of the transactions
      contemplated hereby and thereby (including the Transactions) (i) conflicts
      or will conflict with or constitutes or will constitute a violation of the
      partnership agreement, limited liability company agreement, certificate of
      formation or conversion, certificate or articles of incorporation, bylaws
      or other constituent document of any of the Partnership Entities, (ii)
      conflicts or will conflict with or constitutes or will constitute a breach
      or violation of, or a default (or an event which, with notice or lapse of
      time or both, would constitute such a default) under any indenture,
      mortgage, deed of trust, loan agreement, lease or other agreement or
      instrument to which any of the Partnership Entities is a party or by which
      any of them or any of their respective properties may be bound, (iii)
      violates or will violate any statute, law or regulation or any order,
      judgment, decree or injunction of any court or governmental agency or body
      directed to any of the Partnership Entities or any of their properties in
      a proceeding to which any of them or their property is a party or (iv)
      results or will result in the creation or imposition of any lien, charge
      or encumbrance upon any property or assets of any of the Partnership
      Entities (other than liens created under the Credit Facility), which
      conflicts, breaches, violations, defaults or liens, in the case of clauses
      (ii), (iii) or (iv), would, individually or in the aggregate, have a
      Material Adverse Effect or would materially impair the ability of any of
      the Partnership Entities to perform their obligations under this Agreement
      or the Operative Agreements.

            (s) No Consents. No permit, consent, approval, authorization, order,
      registration, filing or qualification ("Consent") of or with any court,
      governmental agency or body having jurisdiction over any of the
      Partnership Entities or any of their respective properties is required in
      connection with the offering, issuance and sale by the Partnership of the
      Units, the execution, delivery and performance of this Agreement and the
      Operative Agreements by the Partnership Entities party hereto and thereto,
      or the consummation by the Partnership Entities of the transactions
      contemplated hereby and thereby (including the Transactions), except (i)
      as described in the Registration Statement, the Prospectus and the
      Disclosure Package, (ii) for registration of the Units under the 1933 Act
      and Consents required under the Securities Exchange Act of 1934, as
      amended (the "1934 Act") and applicable state securities or "Blue Sky"
      laws in connection with the purchase and distribution of the Units by the
      Underwriters, (iii) for such Consents that have been, or prior to the
      Closing Date will be, obtained, and (iv) for such Consents which, if not
      obtained, would not, individually or in the aggregate, have a

                                       15


      Material Adverse Effect or materially impair the ability of any of the
      Partnership Entities to perform their obligations under this Agreement or
      the Operative Agreements.

            (t) No Default. None of the Partnership Entities is (i) in violation
      of its partnership agreement, limited liability company agreement,
      certificate of formation or conversion, certificate or articles of
      incorporation, bylaws or other constituent document, (ii) in violation of
      any law, statute, ordinance, administrative or governmental rule or
      regulation applicable to it or of any order, judgment, decree or
      injunction of any court or governmental agency or body having jurisdiction
      over it or (iii) in breach, default (or an event which, with notice or
      lapse of time or both, would constitute such a default) or violation in
      the performance of any obligation, agreement or condition contained in any
      bond, debenture, note or any other evidence of indebtedness or in any
      agreement, indenture, lease or other instrument to which it is a party or
      by which it or any of its properties may be bound, which breach, default
      or violation in the case of clause (ii) or (iii) would, if continued, have
      a Material Adverse Effect or materially impair the ability of any of the
      Partnership Entities to perform their obligations under this Agreement or
      the Operative Agreements. To the knowledge of the EVEP Parties, no third
      party to any indenture, mortgage, deed of trust, loan agreement or other
      agreement or instrument to which any of the Partnership Entities is a
      party or by which any of them is bound or to which any of their properties
      is subject, is in breach, default or violation of any such agreement,
      which breach, default or violation would, if continued, have a Material
      Adverse Effect or materially impair the ability of any of the Partnership
      Entities to perform their obligations under this Agreement or the
      Operative Agreements.

            (u) Conformity of Securities to Descriptions in the Disclosure
      Package and the Prospectus. The Units, when issued and delivered in
      accordance with the terms of the Partnership Agreement against payment
      therefor as provided herein, and the Sponsor Units and the Incentive
      Distribution Rights, when issued and delivered in accordance with the
      terms of the Partnership Agreement, will conform in all material respects
      to the descriptions thereof contained in the Registration Statement, the
      Prospectus and the Disclosure Package.

            (v) Independent Public Accountants. The accountants, Deloitte &
      Touche LLP, who have certified or shall certify the audited financial
      statements included in the Registration Statement, the Preliminary
      Prospectus and the Prospectus (or any amendment or supplement thereto),
      were independent registered public accountants with respect to the
      Partnership and the General Partner as required by the 1933 Act and the
      1933 Act Rules and Regulations during the periods covered by the financial
      statements on which they reported.

            (w) Financial Statements. As of June 30, 2006, the Partnership would
      have had, on the consolidated pro forma basis indicated in the Prospectus
      (and any amendment or supplement thereto), a capitalization as set forth
      therein. The historical financial statements (including the related notes
      and supporting schedules) included in the Registration Statement, the
      Preliminary Prospectus and the Prospectus, together with the related notes
      (and any amendment or supplement thereto) comply as to form in all
      material respects with the requirements of Regulation S-X under the 1933
      Act and

                                       16


      present fairly in all material respects the financial position, results of
      operations and cash flows of the entities purported to be shown thereby on
      the basis stated therein at the respective dates or for the respective
      periods to which they apply and have been prepared in accordance with
      generally accepted accounting principles consistently applied throughout
      the periods involved, except to the extent disclosed therein. Any pro
      forma financial statements or other pro forma financial information set
      forth in the Registration Statement, the Prospectus and the Disclosure
      Package (and any amendment or supplement thereto) is accurately presented
      in all material respects and prepared on a basis consistent with the
      audited and unaudited historical financial statements and pro forma
      financial statements, as applicable, from which it has been derived. The
      pro forma financial statements of the Partnership included in the
      Registration Statement, the Preliminary Prospectus and the Prospectus (and
      any amendment or supplement thereto) have been prepared in all material
      respects in accordance with the applicable requirements of Article 11 of
      Regulation S-X of the Commission; the assumptions used in the preparation
      of such pro forma financial statements are, in the opinion of the
      management of the General Partner, reasonable; and the pro forma
      adjustments reflected in such pro forma financial statements have been
      properly applied to the historical amounts in compilation of such pro
      forma financial statements. There are no financial statements (historical
      or pro forma) that are required to be included in the Registration
      Statement, the Prospectus and the Disclosure Package that are not included
      as required.

            (x) Independent Petroleum Engineers. Cawley, Gillespie & Associates,
      Inc. Services, whose report dated December 31, 2005 is referenced in the
      Registration Statement, Prospectus and Preliminary Prospectus and who has
      delivered the letter referred to in Section 7(h) hereof, was, as of the
      date of such report, and is, as of the date hereof, an independent reserve
      engineer with respect to the Partnership.

            (y) Title to Real Property. Upon consummation of the Transactions on
      the Closing Date, the Partnership Entities will have good, valid and
      indefeasible title to all of the interests in oil and gas properties
      underlying the Partnership Entities estimates of their net proved reserves
      contained in the Prospectus and to all other real and personal property
      reflected in the Registration Statement, the Prospectus and any Disclosure
      Package as assets owned by them, in each case, free and clear of all (i)
      liens and security interests or (ii) other claims and other encumbrances
      (other than liens or security interests) except, in each case, (1) as
      described, and subject to the limitations contained, in the Registration
      Statement, the Prospectus and the Disclosure Package or (2) such as do not
      materially interfere with the use of such properties taken as a whole as
      they have been used in the past and are proposed to be used in the future
      as described, and subject to limitations contained, in the Registration
      Statement, the Prospectus and the Disclosure Package; provided that, with
      respect to any real property and buildings held under lease by any
      Partnership Entity, such real property and buildings are held under valid
      and subsisting and enforceable leases with such exceptions as do not
      materially interfere with the use of the properties of the Partnership
      Entities taken as a whole as they have been used in the past as described,
      subject to the limitations contained, in the Registration Statement, the
      Prospectus and the Disclosure Package and are proposed to be used in the
      future as described in contained in the Registration Statement, the
      Prospectus and the Disclosure Package; the leases, mineral interests,
      operating agreements and other contract rights to

                                       17


      which the Partnership Entities are a party give the Partnership Entities
      the right, in all material respects, to explore, develop or produce
      hydrocarbons as described, and subject to the limitations contained, in
      the Registration Statement, the Prospectus and the Disclosure Package. The
      care taken by the Partnership Entities in acquiring or otherwise procuring
      such leases or mineral interests was generally consistent with standard
      industry practices in the areas in which the Partnership Entities operate
      for acquiring or procuring leases and interests therein to explore,
      develop or produce hydrocarbons.

            (z) Information Underlying Reserve Report. The factual information
      underlying the estimates of pro forma reserves of the Partnership
      Entities, which was supplied by the Partnership Entities to Cawley,
      Gillespie & Associates, Inc. For purposes of preparing the reserve
      reports, the estimates of pro forma net proved reserves and standardized
      measure attributable thereto, and the letter (the "Reserve Report Letter")
      of Cawley, Gillespie & Associates, Inc. included as an annex to the
      Prospectus, including, without limitation, production volumes, costs of
      operation and development, current prices for production, agreements
      relating to current and future operations and sales of production, was
      true and correct in all material respects on the dates such estimates were
      made and such information was supplied and was prepared in accordance with
      customary industry practices; other than normal production of the reserves
      and intervening market commodity price fluctuations, the Partnership
      Entities are not aware of any facts or circumstances that would result in
      a material adverse change in the reserves, or the present value of future
      net cash flows therefrom, as described in the Prospectus and as reflected
      in the Reserve Report Letter; estimates of such reserves and present
      values as described in the Pricing Prospectus and reflected in the Reserve
      Report Letter comply in all material respects with the applicable
      requirements of Regulation S-X and Industry Guide 2 under the Securities
      Act.

            (aa) No Material Adverse Change. None of the Partnership Entities
      has sustained, since the date of the latest audited financial statements
      included in the Registration Statement, the Prospectus and the Disclosure
      Package, any material loss or interference with its business from fire,
      explosion, flood or other calamity, whether or not covered by insurance,
      or from any labor dispute or court or governmental action, investigation,
      order or decree, otherwise than as set forth or contemplated in the
      Registration Statement, the Prospectus and the Disclosure Package. Except
      as disclosed in the Registration Statement, the Prospectus and the
      Disclosure Package (or any amendment or supplement thereto), subsequent to
      the respective dates as of which such information is given in the
      Registration Statement, the Prospectus and the Disclosure Package (or any
      amendment or supplement thereto), (i) none of the Partnership Entities has
      incurred any liability or obligation, indirect, direct or contingent, or
      entered into any transactions, not in the ordinary course of business,
      that, singly or in the aggregate, is material to the Partnership Entities,
      (ii) there has not been any material change in the capitalization, or
      material increase in the short-term debt or long-term debt, of any
      Partnership Entity and (iii) there has not been any material adverse
      change, or any development involving or which may reasonably be expected
      to involve, singly or in the aggregate, a prospective material adverse
      change in or affecting the general affairs, business, prospects,
      properties, management, condition (financial or other), partners' equity,
      members' equity, net worth or results of operations of the Partnership
      Entities.

                                       18


            (bb) Legal Proceedings or Contracts to be Described or Filed. There
      are no legal or governmental proceedings pending or, to the knowledge of
      the EVEP Parties, threatened, against any of the Partnership Entities, or
      to which any of the Partnership Entities is a party, or to which any of
      their respective properties is subject, that are required to be described
      in the Registration Statement, the Prospectus and the Disclosure Package
      but are not described as required, and there are no agreements, contracts,
      indentures, leases or other instruments that are required to be described
      in the the Registration Statement, the Prospectus and the Disclosure
      Package or to be filed as exhibits to the Registration Statement that are
      not described or filed as required by the 1933 Act or the 1933 Act Rules
      and Regulations.

            (cc) Certain Relationships and Related Transactions. No
      relationship, direct or indirect, exists between or among any Partnership
      Entity on the one hand, and the directors, managers, officers, members,
      partners, stockholders, customers or suppliers of any Partnership Entity
      on the other hand, that is required to be described in the Prospectus and
      is not so described. There are no outstanding loans, advances (except
      normal advances for business expenses in the ordinary course of business)
      or guarantees of indebtedness by any Partnership Entity to or for the
      benefit of any of the officers, directors or managers of any Partnership
      Entity or their respective family members, except as disclosed in the
      Registration Statement, the Prospectus and the Disclosure Package. No
      Partnership Entity has, in violation of the Sarbanes-Oxley Act of 2002,
      directly or indirectly, extended or maintained credit, arranged for the
      extension of credit or renewed an extension of credit, in the form of a
      personal loan to or for any director, manager or executive officer of any
      Partnership Entity.

            (dd) Rights-of-Way. Upon consummation of the Transactions on the
      Closing Date, each of the Partnership Entities will have such easements,
      rights-of-way, permits or licenses (collectively, "rights-of-way") and
      consents with respect to the transfer of any of the foregoing, as are
      necessary to conduct its business in the manner described, and subject to
      the limitations contained, in the Registration Statement, the Prospectus
      and the Disclosure Package, except for (i) qualifications, reservations
      and encumbrances that would not have a Material Adverse Effect and (ii)
      such rights-of-way or consents that, if not obtained, would not have,
      individually or in the aggregate, a Material Adverse Effect; other than as
      set forth, and subject to the limitations contained, in the Registration
      Statement, the Prospectus and the Disclosure Package, each of the
      Partnership Entities has, or upon consummation of the Transactions at the
      Closing Date will have, fulfilled and performed all of its material
      obligations with respect to such rights-of-way or consents and no event
      has occurred that allows, or after notice or lapse of time would allow,
      revocation or termination thereof or would result in any impairment of the
      rights of the holder of any such rights-of-way or consents, except for
      such revocations, terminations and impairments that would not have a
      Material Adverse Effect; and, except as described in the Registration
      Statement, the Prospectus and the Disclosure Package, none of such
      rights-of-way or consents contains any restriction that is materially
      burdensome to the business of the Partnership Entities, taken as a whole.

            (ee) Sufficiency of Contribution Documents. The Contribution
      Documents were or will be legally sufficient to transfer or convey to the
      Operating Subsidiaries

                                       19


      satisfactory title to, or valid rights to use or manage, all properties
      not already held by them that are, individually or in the aggregate,
      required to enable the Partnership and the Subsidiaries to conduct their
      operations (in all material respects as contemplated by the Prospectus),
      subject to the conditions, reservations and limitations contained in the
      Contribution Documents and those set forth in the Prospectus. The
      Operating Subsidiaries, upon execution and delivery of the Contribution
      Documents, succeeded or will succeed in all material respects to the
      business, assets, properties, liabilities and operations reflected by the
      pro forma financial statements of the Partnership included in the
      Prospectus, except as disclosed in the Prospectus and the Contribution
      Documents.

            (ff) Permits. Each of the Partnership Entities has, or at the
      Closing Date will have, such permits, consents, licenses, franchises,
      certificates and authorizations of governmental or regulatory authorities
      ("permits") as are necessary to own its properties and to conduct its
      business in the manner described in the Disclosure Package and the
      Prospectus, subject to such qualifications as may be set forth in the
      Disclosure Package and the Prospectus and except for such permits that, if
      not obtained, would not, individually or in the aggregate, have a Material
      Adverse Effect; except as set forth in the Registration Statement, the
      Prospectus and the Disclosure Package, each of the Partnership Entities
      has, or at the Closing Date will have, fulfilled and performed all its
      material obligations with respect to such permits which are or will be due
      to have been fulfilled and performed by such date and no event has
      occurred that would prevent the permits from being renewed or reissued or
      which allows, or after notice or lapse of time would allow, revocation or
      termination thereof or results in any impairment of the rights of the
      holder of any such permit, except for such non-renewals, non-issuances,
      revocations, terminations and impairments that would not, individually or
      in the aggregate, have a Material Adverse Effect.

            (gg) Books and Records. Each Partnership Entity (i) makes and keeps
      books, records and accounts, which, in reasonable detail, accurately and
      fairly reflect the transactions and dispositions of its assets and (ii)
      maintains systems of internal accounting controls sufficient to provide
      reasonable assurances that (A) transactions are executed in accordance
      with management's general or specific authorization; (B) transactions are
      recorded as necessary to permit preparation of its financial statements in
      conformity with generally accepted accounting principles and to maintain
      accountability for its assets; (C) access to its assets is permitted only
      in accordance with management's general or specific authorization; and (D)
      the recorded accountability for assets is compared with existing assets at
      reasonable intervals and appropriate action is taken with respect to any
      differences.

            (hh) Disclosure Controls. The General Partner has established and
      maintains disclosure controls and procedures (as such term is defined in
      Rule 13a-14 under the 1934 Act), which (i) are designed to ensure that
      material information relating to the Partnership, including its
      consolidated subsidiaries, is made known to the General Partner's
      principal executive officer and its principal financial officer by others
      within those entities, and (ii) are effective in all material respects to
      perform the functions for which they were established.

                                       20


            (ii) Tax Returns. Each of the Partnership Entities has filed (or has
      obtained extensions with respect to) all material federal, state, local
      and foreign income and franchise tax returns required to be filed through
      the date hereof, which returns are complete and correct in all material
      respects, and has timely paid all taxes due thereon, other than those (i)
      which are being contested in good faith and for which adequate reserves
      have been established in accordance with generally accepted accounting
      principles or (ii) which, if not paid, would not have a Material Adverse
      Effect.

            (jj) Investment Company. None of the Partnership Entities is now,
      and after sale of the Units to be sold by the Partnership hereunder and
      application of the net proceeds from such sale as described in the
      Prospectus under the caption "Use of Proceeds" will be an "investment
      company" or a company "controlled by" an "investment company" within the
      meaning of the Investment Company Act of 1940, as amended (the "Investment
      Company Act").

            (kk) Environmental Compliance. The Partnership Entities (i) are in
      compliance with any and all applicable federal, state and local laws and
      regulations relating to the protection of human health and safety and the
      environment or imposing liability or standards of conduct concerning any
      Hazardous Material (as hereinafter defined) ("Environmental Laws"), (ii)
      have received all permits required of them under applicable Environmental
      Laws to conduct their respective businesses, (iii) are in compliance with
      all terms and conditions of any such permit and (iv) do not have any
      liability in connection with the release into the environment of any
      Hazardous Material, except, in each case, where such noncompliance with
      Environmental Laws, failure to receive required permits, failure to comply
      with the terms and conditions of such permits or liability would not,
      individually or in the aggregate, have a Material Adverse Effect. The term
      "Hazardous Material" means (A) any "hazardous substance" as defined in the
      Comprehensive Environmental Response, Compensation and Liability Act of
      1980, as amended, (B) any "hazardous waste" as defined in the Resource
      Conservation and Recovery Act, as amended, (C) any petroleum or petroleum
      product, (D) any polychlorinated biphenyl and (E) any pollutant or
      contaminant or hazardous, dangerous or toxic chemical, material, waste or
      substance regulated under or within the meaning of any other Environmental
      Law.

            (ll) Sarbanes-Oxley Act of 2002. The Partnership is in compliance in
      all material respects with all applicable provisions of the Sarbanes-Oxley
      Act of 2002 and the rules and regulations of the SEC and the NASDAQ Global
      Market that pertain thereto that are effective.

            (mm) No Labor Dispute. No labor dispute with the employees of the
      Partnership Entities exists or, to the knowledge of any of the EVEP
      Parties, is imminent or threatened that is reasonably likely to result in
      a Material Adverse Effect.

            (nn) Insurance. A Partnership Entity, EVMP or EVOC maintains
      insurance covering the properties, operations, personnel and businesses of
      the Partnership Entities against such losses and risks and in such amounts
      as is reasonably adequate for the conduct of their respective businesses
      and the value of their respective properties and as

                                       21


      is customary for companies engaged in similar businesses in similar
      industries. None of the Partnership Entities, EVMP or EVOC has received
      notice from any insurer or agent of such insurer that substantial capital
      improvements or other expenditures will have to be made in order to
      continue such insurance (including after giving effect to the
      Transactions), and all such insurance is outstanding and duly in force on
      the date hereof and will be outstanding and duly in force on the Closing
      Date.

            (oo) Litigation. Except as described in the Registration Statement,
      the Prospectus and the Disclosure Package, there is (i) no action, suit or
      proceeding before or by any court, arbitrator or governmental agency, body
      or official, domestic or foreign, now pending or, to the knowledge of the
      EVEP Parties, threatened, to which any of the Partnership Entities is or
      may be a party or to which the business or property of any of the
      Partnership Entities is or may be subject, (ii) no injunction, restraining
      order or order of any nature issued by a federal or state court or foreign
      court of competent jurisdiction to which any of the Partnership Entities
      is or may be subject, that, in the case of clauses (i) and (ii) above, is
      reasonably likely to (A) individually or in the aggregate have a Material
      Adverse Effect, (B) prevent or result in the suspension of the offer,
      issuance or sale of the Units, or (C) in any manner draw into question the
      validity of this Agreement.

            (pp) No Distribution of Other Offering Materials. None of the
      Partnership Entities have distributed and, prior to the later to occur of
      (i) the Closing Date and (ii) completion of the distribution of the Units,
      will not distribute, any prospectus (as defined under the 1933 Act) in
      connection with the offering and sale of the Units other than any
      Prospectus, any Preliminary Prospectus, or any Permitted Free Writing
      Prospectus.

            (qq) Listing. The Units have been approved for quotation on the
      NASDAQ Global Market, subject only to official notice of issuance.

            (rr) Directed Unit Sales. None of the Directed Units (as defined in
      Section 6(a)(xvi) below) distributed in connection with the Directed Unit
      Program (as defined in Section 6(a)(xvi) below) will be offered or sold
      outside of the United States. None of the Partnership Entities has
      offered, or caused the Underwriters to offer, Units to any person pursuant
      to the Directed Unit Program with the specific intent to unlawfully
      influence (i) a customer or supplier of the Partnership Entities to alter
      the customer's or supplier's level or type of business with the
      Partnership Entities, or (ii) a trade journalist or publication to write
      or publish favorable information about the Partnership Entities or their
      products or services.

            (ss) Brokers. Except as described in the Prospectus, there are no
      contracts, agreements or understandings between any Partnership Entity and
      any person that would give rise to a valid claim against any Partnership
      Entity or any Underwriter for a brokerage commission, finder's fee or
      other like payment in connection with this offering of the Units.

            (tt) Market Stabilization. None of the Partnership Entities (i) has
      taken, and none of such persons shall take, directly or indirectly, any
      action designed to cause or

                                       22


      result in, or which has constituted or which might reasonably be expected
      to constitute, the stabilization or manipulation of the price of the Units
      to facilitate the sale or resale of the Units in violation of any law,
      rule or regulation or (ii) since the initial filing of the Registration
      Statement, except as contemplated by this Agreement, (A) has sold, bid
      for, purchased or paid anyone any compensation for soliciting purchases of
      the Units or (B) has paid or agreed to pay to any person any compensation
      for soliciting another to purchase any other securities of the
      Corporation.

            (uu) Statistical and Market-Related Data. All statistical or
      market-related data included in the Registration Statement, the
      Preliminary Prospectuses, and the Disclosure Package, if any, are based on
      or derived from sources that the Partnership reasonably believes to be
      reliable and accurate, and the Partnership has obtained the written
      consent to the use of such data from such sources to the extent required.

            (vv) NASD Affiliations. To the Partnership's knowledge, there are no
      affiliations or associations between any member of the National
      Association of Securities Dealers, Inc. ("NASD") and any of the
      Partnership's officers or directors or the Partnership's 5% or greater
      securityholders, except as set forth in the Registration Statement, the
      Preliminary Prospectuses and the Prospectus.

      Any certificate signed by any officer of any Partnership Entity or EVMP
and delivered to the Underwriters or to counsel for the Underwriters pursuant to
this Agreement shall be deemed a representation and warranty by such Partnership
Entity or EVMP to each Underwriter as to the matters covered thereby.

      6.    ADDITIONAL COVENANTS.

            (a) The EVEP Parties (but not including the EnCap Entities) jointly
      and severally covenant and agree with the several Underwriters with
      respect to the provisions of this Section 6(a), and the EnCap Entities
      severally as to themselves only covenant and agree with the several
      Underwriters with respect to Section 6(a)(xiii) solely as such section
      relates to the EnCap Entities, that:

                  (i) The Partnership will timely transmit copies of the
            Prospectus in a form approved by the Underwriters, and any
            amendments or supplements thereto (subject to the provisions of this
            Section 5), to the SEC for filing pursuant to Rule 424(b) of the
            1933 Act Rules and Regulations or, if applicable, Rule 430A(a)(3) of
            the 1933 Act Rules and Regulations.

                  (ii) The Partnership will deliver to each of the Underwriters,
            and to counsel for the Underwriters (i) a signed copy of the
            Registration Statement as originally filed, including copies of
            exhibits thereto, of any amendments and supplements to the
            Registration Statement and (ii) a signed copy of each consent and
            certificate included in, or filed as an exhibit to, the Registration
            Statement as so amended or supplemented; the Partnership will
            deliver to the Underwriters as soon as practicable after the date of
            this Agreement as many copies of the Preliminary Prospectus,
            Prospectus and any amendment or supplement thereto as

                                       23


            the Underwriters may reasonably request for the purposes
            contemplated by the 1933 Act; if there is a post-effective amendment
            to the Registration Statement that is not effective under the 1933
            Act, the Partnership will use its best efforts to cause the
            post-effective amendment to the Registration Statement to become
            effective as promptly as possible, and it will notify the
            Underwriters, promptly after it shall receive notice thereof, of the
            time when the post-effective amendment to the Registration Statement
            has become effective; the Partnership will promptly advise the
            Underwriters of any request of the SEC for amendment of the
            Registration Statement or for supplement to the Prospectus or for
            any additional information, and of the issuance by the SEC or any
            state or other jurisdiction or other regulatory body of any stop
            order under the 1933 Act or other order suspending the effectiveness
            of the Registration Statement (as amended or supplemented) or
            preventing or suspending the use of the Preliminary Prospectus, any
            Permitted Free Writing Prospectus or the Prospectus or suspending
            the qualification or registration of the Units for offering or sale
            in any jurisdiction, and of the institution or threat of any
            proceedings therefor, of which the Partnership shall have received
            notice or otherwise have knowledge prior to the completion of the
            distribution of the Units; and the Partnership will use its best
            efforts to prevent the issuance of any such stop order or other
            order and, if issued, to secure the prompt removal thereof.

                  (iii) The Partnership will not file any amendment or
            supplement to the Registration Statement, the Prospectus, Permitted
            Free Writing Prospectus or any other free writing prospectus (or any
            other prospectus relating to the Units filed pursuant to Rule 424(b)
            of the 1933 Act Rules and Regulations that differs from the
            Prospectus as filed pursuant to such Rule 424(b)), of which the
            Underwriters shall not previously have been advised or to which the
            Underwriters shall have reasonably objected in writing after being
            so advised unless the Partnership shall have determined based upon
            the advice of counsel that such amendment or supplement is required
            by law; and the Partnership will promptly notify the Underwriters
            after it shall have received notice thereof of the time when any
            amendment to the Registration Statement, the Prospectus or Permitted
            Free Writing Prospectus becomes effective or when any supplement to
            the Prospectus has been filed.

                  (iv) During the period when a prospectus relating to any of
            the Units is required to be delivered under the 1933 Act by any
            Underwriter or dealer, the Partnership will comply, at its own
            expense, with all requirements imposed by the 1933 Act and the 1933
            Act Rules and Regulations, so far as necessary to permit the
            continuance of sales of or dealing in the Units during such period
            in accordance with the provisions hereof and as contemplated by the
            Prospectus.

                  (v) If, during the period when a prospectus relating to any of
            the Units is required to be delivered under the 1933 Act by any
            Underwriter or dealer, (i) any event relating to or affecting the
            Partnership or of which the Partnership shall be advised in writing
            by the Underwriters shall occur as a result of which, in the opinion
            of the Partnership or the counsel for the Underwriters, the
            Prospectus

                                       24


            or any Permitted Free Writing Prospectus, as then amended or
            supplemented would include any untrue statement of a material fact
            or omit to state a material fact necessary in order to make the
            statements therein, in the light of the circumstances under which
            they were made, not misleading or (ii) it shall be necessary to
            amend or supplement the Registration Statement or the Prospectus to
            comply with the 1933 Act, the 1933 Act Rules and Regulations, the
            1934 Act or the 1934 Act Rules and Regulations, the Partnership will
            forthwith at its expense prepare and file with the SEC, and furnish
            to the Underwriters a reasonable number of copies of, such amendment
            or supplement or other filing that will correct such statement or
            omission or effect such compliance.

                  (vi) During the period when a prospectus relating to any of
            the Units is required to be delivered under the 1933 Act by any
            Underwriter or dealer, the Partnership will furnish such proper
            information as may be lawfully required and otherwise cooperate with
            the Underwriters in qualifying the Units for offer and sale under
            the securities or blue sky laws of such jurisdictions as the
            Underwriters may reasonably designate and will file and make such
            statements or reports as are or may be reasonably necessary;
            provided, however, that the Partnership shall not be required to
            qualify as a foreign partnership or to qualify as a dealer in
            securities or to file a general consent to service of process under
            the laws of any jurisdiction.

                  (vii) In accordance with Section 11(a) of the 1933 Act and
            Rule 158 of the 1933 Act Rules and Regulations, the Partnership will
            make generally available to its security holders, an earning
            statement (which need not be audited) in reasonable detail covering
            the 12-month period beginning not later than the first day of the
            month next succeeding the month in which occurred the effective date
            (within the meaning of Rule 158) of the Registration Statement as
            soon as practicable after the end of such period.

                  (viii) The Partnership will furnish or make available to its
            security holders annual reports containing financial statements
            audited by independent public accountants and quarterly reports
            containing financial statements and financial information which may
            be unaudited. The Partnership will, for a period of two years from
            the Closing Date, furnish or make available to the Underwriters via
            the Commissions' Electronic Data Gathering, Analysis and Retrieval
            (EDGAR) system or its website a copy of each annual report,
            quarterly report, current report and all other documents, reports
            and information furnished by the Partnership to holders of Units
            (excluding any periodic income tax reporting) or filed with any
            securities exchange or market pursuant to the requirements of such
            exchange or market or with the SEC pursuant to the 1933 Act or the
            1934 Act. The Partnership will deliver or make available to the
            Underwriters similar reports with respect to any significant
            subsidiaries, as that term is defined in the 1933 Act Rules and
            Regulations, which are not consolidated in the Partnership's
            financial statements.

                                       25


                  (ix) The Partnership and the General Partner will not, during
            the 180 days after the date of the Prospectus, without the prior
            written consent of A.G. Edwards & Sons, Inc., which consent will not
            be unreasonably withheld, directly or indirectly, (i) offer for
            sale, sell, pledge or otherwise dispose of (or enter into any
            transaction or device which is designed to, or could be expected to,
            result in the disposition by any person at any time in the future
            of) any Common Units or securities convertible into or exchangeable
            for Common Units (other than Common Units issued (a) pursuant to
            employee benefit plans, qualified unit option plans or other
            employee compensation plans existing on the date hereof or pursuant
            to currently outstanding options, warrants or rights, (b) to
            affiliates, (c) in connection with acquisitions of assets accretive
            to the common unitholders or businesses in which common units are
            issued as consideration, or (d) overallotment option; provided,
            however, any such recipient of common units will agree to be bound
            by these provisions for the remainder of the 180-day period) or sell
            or grant options, rights or warrants with respect to any Common
            Units or securities convertible into or exchangeable for Common
            Units (other than the grant of options pursuant to option plans
            existing or the date hereof) or (ii) enter into any swap or other
            derivatives transaction that transfers to another, in whole or in
            part, any of the economic benefits or risks of ownership of such
            Common Units, whether any such transaction described in clause (1)
            or (2) above is to be settled by delivery of Common Units or other
            securities, in cash or otherwise. Notwithstanding the foregoing or
            the provisions of the letters referred to in paragraph (xiii) below,
            for the purpose of facilitating research coverage of the Partnership
            by the Underwriters and compliance with NASD Rule 2711, if (1)
            during the last 17 days of the 180-day restricted period the
            Partnership issues an earnings release or material news or a
            material event relating to the Partnership occurs or (2) prior to
            the expiration of the 180-day restricted period, the Partnership
            announces that it will release earnings results during the 16-day
            period beginning on the last day of the 180-day period, then the
            restrictions imposed by this paragraph (i) and the letters referred
            to in paragraph (xiii) below shall continue to apply until the
            expiration of the 18-day period beginning on the issuance of the
            earnings release or the occurrence of the material news or material
            event.

                  (x) The Partnership will apply the proceeds from the sale of
            the Units as set forth in the description under "Use of Proceeds" in
            the Prospectus and will file with the SEC such information on Form
            10-K or Form l0-Q as may be required by Rule 463 of the 1933 Act
            Rules and Regulations.

                  (xi) The Partnership will promptly provide the Underwriters
            with copies of all correspondence to and from, and all documents
            issued to and by, the SEC in connection with the registration of the
            Units under the 1933 Act.

                  (xii) The Partnership will apply for listing of the Units on
            the NASDAQ Global Market and will use its best efforts to effect
            that listing, subject to notice of issuance, prior to the Closing
            Date.

                                       26


                  (xiii) The EVEP Parties will cause the directors and officers
            of the GP LLC, the members and executive officers of EnerVest
            Management GP, L.C., a Texas limited liability company, EVMP, EVOC,
            CGAS, each of the Sponsor Entities and EV Investors, to furnish to
            the Underwriters, on or prior to the date of this Agreement, a
            letter or letters, in form and substance satisfactory to counsel for
            the Underwriters, pursuant to which each such person shall agree not
            to directly or indirectly, (1) offer for sale, sell, pledge or
            otherwise dispose of (or enter into any transaction or device which
            is designed to, or could be expected to, result in the disposition
            by any person at any time in the future of) any Common Units or
            securities convertible into or exchangeable for Common Units or (2)
            enter into any swap or other derivatives transaction that transfers
            to another, in whole or in part, any of the economic benefits or
            risks of ownership of such Common Units, whether any such
            transaction described in clause (1) or (2) above is to be settled by
            delivery of Common Units or other securities, in cash or otherwise,
            in each case during the 180 days after the date of the Prospectus,
            without the prior written consent of A.G. Edwards & Sons, Inc.

                  (xiv) The Partnership agrees that, unless it has obtained or
            will obtain the prior written consent of A.G. Edwards & Sons, Inc.,
            it has not made and will not make any offer relating to the
            Securities that would constitute an Issuer Free Writing Prospectus
            or that would otherwise constitute a "free writing prospectus" (as
            defined in Rule 405) required to be filed by the Partnership with
            the SEC or retained by the Partnership under Rule 433; provided that
            the prior written consent of the parties hereto shall be deemed to
            have been given in respect of the free writing prospectuses included
            in Schedule III hereto and any electronic road show. The Partnership
            agrees that (x) it has treated and will treat, as the case may be,
            each Permitted Free Writing Prospectus as an Issuer Free Writing
            Prospectus and (y) it has complied and will comply, as the case may
            be, with the requirements of Rules 164 and 433 applicable to any
            Permitted Free Writing Prospectus, including in respect of timely
            filing with the SEC, legending and record keeping.

                  (xv) If, at any time prior to the filing of the Prospectus
            pursuant to Rule 424(b), any event occurs as a result of which the
            Disclosure Package would include any untrue statement of a material
            fact or omit to state any material fact necessary to make the
            statements therein in the light of the circumstances under which
            they were made at such time not misleading, the Partnership will (i)
            notify promptly A.G. Edwards & Sons, Inc. so that any use of the
            Disclosure Package may cease until it is amended or supplemented;
            (ii) amend or supplement the Disclosure Package to correct such
            statement or omission; and (iii) supply any amendment or supplement
            to you in such quantities as you may reasonably request.

                  (xvi) It is understood that up to 195,000 of the Firm Units
            (the "Directed Units") will initially be reserved by the
            Underwriters for offer and sale to officers, directors, employees
            and persons having business relationships with the Partnership
            Entities ("Directed Unit Participants") upon the terms and
            conditions

                                       27


            set forth in the Prospectus (the "Directed Unit Program") and in
            accordance with the rules and regulations of the NASD and that any
            allocation of such Directed Units among such persons will be made in
            accordance with timely directions received by Raymond James &
            Associates, Inc. from the Partnership. Under no circumstances will
            Raymond James & Associates, Inc. or any Underwriter be liable to any
            Partnership Entity or to any Directed Unit Participant for any
            action taken or omitted to be taken in good faith in connection with
            such Directed Unit Program. To the extent that any Directed Units
            are not affirmatively reconfirmed for purchase by any Directed Unit
            Participant on or immediately after the date of this Agreement, such
            Directed Units may be offered to the public as part of the public
            offering contemplated hereby.

                  (xvii) If the Partnership elects to rely on Rule 462(b) of the
            1933 Act Rules and Regulations, the Partnership shall both file an
            Abbreviated Registration Statement with the SEC in compliance with
            Rule 462(b) and pay the applicable fees in accordance with Rule 111
            of the 1933 Act Rules and Regulations by the earlier of (i) 10:00
            p.m., New York time, on the date of this Agreement, and (ii) the
            time that confirmations are given or sent, as specified by Rule
            462(b)(2).

            (b) The several Underwriters jointly and severally covenant and
      agree with the Partnership that each Underwriter, severally and not
      jointly, agrees with the Partnership that, unless it has obtained or will
      obtain, as the case may be, the prior written consent of the Partnership,
      it has not made and will not make any offer relating to the Securities
      that would constitute an Issuer Free Writing Prospectus or that would
      otherwise constitute a "free writing prospectus" (as defined in Rule 405)
      required to be filed by the Partnership with the SEC or retained by the
      Partnership under Rule 433; provided that the prior written consent of the
      parties hereto shall be deemed to have been given in respect of the free
      writing prospectuses included in Schedule III hereto and any electronic
      road show.

      7. CONDITIONS OF UNDERWRITERS' OBLIGATIONS. The several obligations of the
Underwriters to purchase and pay for the Units, as provided herein, shall be
subject to the accuracy, as of the date hereof and as of the Closing Date (and,
if applicable, the Option Closing Date), of the representations and warranties
of the EVEP Parties contained herein, to the performance by the EVEP Parties of
their covenants and obligations hereunder, and to the following additional
conditions:

            (a) The Registration Statement and all post-effective amendments
      thereto shall have become effective not later than 5:30 p.m., New York
      time, on the date hereof, or, with the consent of the Underwriters, at a
      later date and time, not later than 1:00 p.m., New York time, on the first
      business day following the date hereof, or at such later date and time as
      may be approved by the Underwriters; if the Partnership has elected to
      rely on Rule 462(b) of the 1933 Act Rules and Regulations, the Abbreviated
      Registration Statement shall have become effective not later than the
      earlier of (i) 10:00 p.m. New York time, on the date hereof, or (ii) at
      such later date and time as may be approved by the Underwriters. All
      filings required by Rule 424 and Rule 430A of the 1933 Act Rules and
      Regulations shall have been made. No stop order suspending the
      effectiveness of the Registration Statement or preventing or suspending
      the use of the Prospectus or any

                                       28


      Permitted Free Writing Prospectus shall have been issued and no proceeding
      for that purpose shall have been initiated or, to the knowledge of the
      Partnership or any Underwriter, threatened or contemplated by the SEC, and
      any request of the SEC for additional information (to be included in the
      Registration Statement or the Prospectus or otherwise) shall have been
      complied with to the reasonable satisfaction of the Underwriters.

            (b) No Underwriter shall have advised the Partnership on or prior to
      the Closing Date (and, if applicable, the Option Closing Date), that the
      Registration Statement, any Preliminary Prospectus or Prospectus, any
      Permitted Free Writing Prospectus or any amendment or supplement thereto
      contains an untrue statement of fact which, in the opinion of the
      Underwriters (upon the advice of counsel) is material, or omits to state a
      fact which, in the opinion of the Underwriters (upon the advice of
      counsel) is material and is required to be stated therein or is necessary
      to make the statements therein, in the light of the circumstances under
      which they were made, not misleading.

            (c) On the Closing Date (and, if applicable, the Option Closing
      Date), the Underwriters shall have received the opinion of Haynes and
      Boone, LLP, counsel for the Partnership, addressed to them and dated the
      Closing Date (and, if applicable, the Option Closing Date), in form and
      substance reasonably satisfactory to the Underwriters, to the effect set
      forth on Exhibit A hereto.

            (d) On the Closing Date, the Underwriters shall have received the
      opinion of Vorys, Sater, Seymour and Pease, LLP, opining as to the laws of
      Ohio, Waters, Warner & Harris, PLLC, opining as to the laws of West
      Virginia and C. Randall Lowen, opining as to the laws of Louisiana,
      addressed to the Underwriters and dated the Closing Date (and, if
      applicable, the Option Closing Date), in form and substance reasonably
      satisfactory to the Underwriters, to the effect set forth on Exhibits B-1,
      B-2 and B-3 hereto.

            (e) The Underwriters shall have received on the Closing Date (and,
      if applicable, the Option Closing Date), from Vinson & Elkins L.L.P.,
      counsel to the Underwriters, such opinion or opinions, dated the Closing
      Date (and, if applicable, the Option Closing Date) with respect to such
      matters as the Underwriters may reasonably require; and the EVEP Parties
      shall have furnished to such counsel such documents as they reasonably
      request for the purposes of enabling them to review or pass on the matters
      referred to in this Section 7 and in order to evidence the accuracy,
      completeness and satisfaction of the representations, warranties and
      conditions herein contained.

            (f) At the time of execution of this Agreement, the Underwriters
      shall have received from Deloitte & Touche LLP a letter or letters, in
      form and substance reasonably satisfactory to the Underwriters, addressed
      to the Underwriters and dated the date hereof and covering the matters
      described in Exhibit C hereto including (i) confirming that they are
      independent public accountants within the meaning of the Act and are in
      compliance with the applicable requirements relating to the qualification
      of accountants under Rule 2-01 of Regulation S-X of the Commission and
      (ii) stating, as of

                                       29


      the date hereof (or, with respect to matters involving changes or
      developments since the respective dates as of which specified financial
      information is given in the Registration Statement, the Prospectus, any
      Preliminary Prospectus and any Permitted Free Writing Prospectuses, as of
      a date not more than five days prior to the date hereof), the conclusions
      and findings of such firm with respect to the various financial
      information in the Registration Statement, the Prospectus, any Preliminary
      Prospectus and any Permitted Free Writing Prospectuses and other matters
      ordinarily covered by accountants' "comfort letters" to underwriters in
      connection with registered public offerings.

            (g) With respect to the letter or letters of Deloitte & Touche LLP
      referred to in the preceding paragraph and delivered to the Underwriters
      concurrently with the execution of this Agreement (the "initial letters"),
      the Partnership shall have furnished to the Underwriters a letter (the
      "bring-down letter") of such accountants, in form and substance reasonably
      satisfactory to the Underwriters, addressed to the Underwriters and dated
      the Closing Date (or if applicable, the Option Closing Date) (i)
      confirming that they are independent public accountants within the meaning
      of the Act and are in compliance with the applicable requirements relating
      to the qualification of accountants under Rule 2-01 of Regulation S-X of
      the Commission, (ii) stating, as of the date of the bring-down letter (or,
      with respect to matters involving changes or developments since the
      respective dates as of which specified financial information is given in
      the Registration Statement, the Prospectus, any Preliminary Prospectus and
      any Permitted Free Writing Prospectuses, as of a date not more than five
      days prior to the date of the bring-down letter), the conclusions and
      findings of such firm with respect to the financial information and other
      matters covered by the initial letters and (iii) confirming in all
      material respects the conclusions and findings set forth in the initial
      letters.

            (h) At the time of execution of this Agreement, the Underwriters
      shall have received from Cawley, Gillespie & Associates, Inc. a letter, in
      form and substance reasonably satisfactory to the Underwriters, addressed
      to the Underwriters and dated the date hereof covering the matters
      described in Exhibit D.

            (i) With respect to the letter of Cawley, Gillespie & Associates,
      Inc. referred to in the preceding paragraph and delivered to the
      Underwriters concurrently with the execution of this Agreement, the
      Partnership shall have furnished to the Underwriters a letter of such
      reserve engineers, addressed to the Underwriters and dated each of the
      Closing Date and the Option Closing Date, if any, confirming in all
      material respects covering the matters in the letter referred to in the
      preceding paragraph.

            (j) Except as set forth in the Registration Statement, the
      Prospectus and the Disclosure Package, (i) none of the Partnership
      Entities shall have sustained since the date of the latest audited
      financial statements included in the Registration Statement and in the
      Prospectus any loss or interference with its business from fire,
      explosion, flood or other calamity, whether or not covered by insurance,
      or from any labor dispute or court or governmental action, order,
      investigation or decree; and (ii) subsequent to the respective dates as of
      which such information is given in the Registration Statement and the
      Prospectus (or any amendment or supplement thereto), none of the
      Partnership Entities shall have incurred any liability or obligation,
      direct or contingent, or entered into any

                                       30


      transactions, and there shall not have been any change in the
      capitalization or short-term or long-term debt of the Partnership Entities
      or any change, or any development involving or which might reasonably be
      expected to involve a prospective change in the condition (financial or
      other), net worth, partners' or members' equity, business, affairs,
      management, prospects, results of operations or cash flow of the
      Partnership Entities, the effect of which, in any such case described in
      clause (i) or (ii), is in the judgment of the Underwriters so material or
      adverse as to make it impracticable or inadvisable to proceed with the
      public offering or the delivery of the Units being delivered on such
      Closing Date (and, if applicable, the Option Closing Date) on the terms
      and in the manner contemplated in the Prospectus.

            (k) There shall not have occurred any of the following: (i) a
      suspension or material limitation in trading in securities generally on
      the NASDAQ Global Market, or the establishing on such market by the SEC or
      by such market of minimum or maximum prices which are not in force and
      effect on the date hereof; (ii) a suspension or material limitation in
      trading in the Partnership's securities on the NASDAQ Global Market or the
      establishing on such market by the SEC or by such market of minimum or
      maximum prices which are not in force and effect on the date hereof, (iii)
      a general moratorium on commercial banking activities declared by either
      federal or applicable state authorities; (iv) the outbreak or escalation
      of hostilities involving the United States or the declaration by the
      United States of a national emergency or war, which in the judgment of the
      Underwriters makes it impracticable or inadvisable to proceed with the
      public offering or the delivery of the Units in the manner contemplated in
      the Prospectus; or (v) any calamity or crisis, change in national,
      international or world affairs, act of God, change in the international or
      domestic markets, or change in the existing financial, political or
      economic conditions in the United States or elsewhere, the effect of which
      on the financial markets of the United States is such as to make it in the
      judgment of the Underwriters impracticable or inadvisable to proceed with
      the public offering or the delivery of the Units in the manner
      contemplated in the Prospectus.

            (l) The Underwriters shall have received certificates, dated the
      Closing Date (and, if applicable, the Option Closing Date) and signed by
      chief executive officer and the chief financial officer, in their
      capacities as such, (or persons holding similar positions, as applicable)
      of each of the EVEP Parties, stating that:

                  (i) the conditions set forth in Section 7(a) have been fully
            satisfied;

                  (ii) such EVEP Party has examined the Registration Statement,
            the Prospectus, the Disclosure Package and any amendment or
            supplement thereto, as well as each electronic roadshow used in
            connection with the offering, and (A) nothing has come to such EVEP
            Party's attention that would lead it to believe that, as of the
            Effective Date, the Registration Statement included any untrue
            statement of a material fact or omitted to state material fact
            required to be stated therein or necessary to make the statements
            therein not misleading, and as of its issue date and as of the
            Closing Date (and, if applicable, the Option Closing Date), the
            Prospectus, the Disclosure Package and any amendment or supplement
            thereto, as well as each electronic roadshow used in connection with
            the offering,

                                       31


            as of their respective effective, issue or filing dates, included
            any untrue statement of a material fact or omitted to state material
            fact necessary to make the statements therein, in the light of the
            circumstances under which they were made, not misleading, and (B)
            since the Effective Date, there has occurred no event required to be
            set forth in an amendment or supplement to the Registration
            Statement or the Prospectus which has not been so set forth;

                  (iii) all representations and warranties made herein by such
            EVEP Party are true and correct at such Closing Date, with the same
            effect as if made on and as of such Closing Date; and all agreements
            herein to be performed or complied with by such EVEP Party on or
            prior to such Closing Date have been duly performed and complied
            with by such EVEP Party;

                  (iv) no event contemplated by Section 7(j) has occurred; and

                  (v) covering such other matters as the Underwriters may
            reasonably request.

            (m) The EVEP Parties shall not have failed, refused, or been unable,
      at or prior to the Closing Date (and, if applicable, the Option Closing
      Date) to have performed any agreement on their part to be performed or any
      of the conditions herein contained and required to be performed or
      satisfied by them at or prior to such Closing Date.

            (n) The Partnership shall have furnished to the Underwriters at the
      Closing Date (and, if applicable, the Option Closing Date) such further
      information, opinions, certificates, letters and documents as the
      Underwriters may have reasonably requested.

            (o) The NASDAQ Global Market shall have approved the Units for
      quotation, subject only to official notice of issuance.

            (p) The Underwriters shall have received duly and validly executed
      letter agreements referred to in Section 6(a)(xiii) hereof.

            (q) The Underwriters shall have received evidence satisfactory to
      them that each of the Transactions shall have occurred or will occur as of
      the Closing Date, in each case as described in the Prospectus without
      modification, change or waiver, except for such modifications, changes or
      waivers as have been specifically identified to the Underwriters and
      which, in the judgment of the Underwriters, do not make it impracticable
      or inadvisable to proceed with the offering and delivery of the Units on
      the Closing Date on the terms and in the manner contemplated in the
      Prospectus.

      All such opinions, certificates, letters and documents will be in
compliance with the provisions hereof only if they are reasonably satisfactory
in form and substance to the Underwriters and to Vinson & Elkins L.L.P., counsel
for the several Underwriters. The Partnership will furnish the Underwriters with
such signed and conformed copies of such opinions, certificates, letters and
documents as they may request.

                                       32


      In accordance with the provisions of Section 11, hereof, this Agreement
may be terminated by the Underwriters at any time at or prior to the Closing
Date by notice to the Partnership if any condition specified in Section 7 shall
not have been satisfied on or prior to the Closing Date

      8.    INDEMNIFICATION AND CONTRIBUTION.

            (a) Subject to the limitation set forth in Section 8(e) below with
      respect to the EnCap Entities, the EVEP Parties will indemnify and hold
      harmless each of the Underwriters from and against any losses, damages or
      liabilities, joint or several, to which the Underwriters may become
      subject, under the 1933 Act, or otherwise, insofar as such losses, damages
      or liabilities (or actions or claims in respect thereof) arise out of or
      are based upon (i) an untrue statement or alleged untrue statement of a
      material fact contained in (A) any Preliminary Prospectus, the
      Registration Statement, the Prospectus or any amendment or supplement
      thereto, (B) any Permitted Free Writing Prospectus used or referred to in
      any "free writing prospectus" (as defined in Rule 405) used or referred to
      by any Underwriter, or (C) any Blue Sky application or other document
      prepared or executed by any of the Partnership Entities (or based upon any
      written information furnished by any of the Partnership Entities or (ii)
      the omission or alleged omission to state therein a material fact required
      to be stated therein or necessary to make the statements therein, in light
      of the circumstances in which they were made, not misleading, and will
      reimburse each of the Underwriters for any legal or other out-of-pocket
      expenses incurred by such Underwriter in connection with investigating,
      preparing, pursuing or defending against or appearing as a third party
      witness in connection with any such loss, damage, liability or action or
      claim, including, without limitation, any investigation or proceeding by
      any governmental agency or body, commenced or threatened, including the
      reasonable fees and expenses of counsel to the indemnified party, as such
      expenses are incurred (including such losses, damages, liabilities or
      expenses to the extent of the aggregate amount paid in settlement of any
      such action or claim, provided that (subject to Section 8(c) hereof) any
      such settlement is effected with the written consent of the General
      Partner); provided, however, that the EVEP Parties shall not be liable in
      any such case to the extent, but only to the extent, that any such loss,
      damage or liability arises out of or is based upon an untrue statement or
      alleged untrue statement or omission or alleged omission made in any
      Preliminary Prospectus, the Registration Statement, the Prospectus, any
      Permitted Free Writing Prospectus or in any such amendment or supplement
      thereto or any Blue Sky Application, in reliance upon and in conformity
      with written information relating to the Underwriters furnished to the
      EVEP Parties by you, expressly for use in the preparation thereof (as
      provided in Section 14 hereof).

            In connection with the offer and sale of the Directed Units, Subject
      to the limitation set forth in Section 8(e) below with respect to the
      EnCap Entities, the EVEP Parties, jointly and severally, will indemnify
      and hold harmless Raymond James & Associates, Inc. from and against any
      losses, damages or liabilities (or actions or claims in respect thereof)
      which (i) arise out of or are based upon, any untrue statement or alleged
      untrue statement of a material fact contained in any material prepared by
      or with the approval of any Partnership Entity for distribution to
      Directed Unit Participants in

                                       33


      connection with the Directed Unit Program or any omission or alleged
      omission to state therein a material fact required to be stated therein or
      necessary to make the statements therein not misleading, (ii) arise out of
      or are based upon the failure of any Directed Unit Participant to pay for
      and accept delivery of Directed Units that the Directed Unit Participant
      agreed to purchase or (iii) are otherwise related to the Directed Unit
      Program, other than losses, damages or liabilities (or expenses relating
      thereto) finally judicially determined to have resulted directly from the
      bad faith or gross negligence or willful misconduct of Raymond James &
      Associates, Inc. The EVEP Parties, jointly and severally, will reimburse
      each Underwriter for any legal or other expenses incurred by such
      Underwriter in connection with investigating, preparing, pursuing or
      defending against or appearing as a third party witness in connection with
      any such loss, damage, liability or action or claim, including, without
      limitation, any investigation or proceeding by any governmental agency or
      body, commenced or threatened, including the reasonable fees and expenses
      of counsel to the indemnified party, as such expenses are incurred
      (including such losses, damages, liabilities or expenses to the extent of
      the aggregate amount paid in settlement of any such action or claim,
      provided that (subject to Section 8(c) hereof) any such settlement is
      effected with the written consent of the Partnership).

            (b) Each of the Underwriters, severally and not jointly, will
      indemnify and hold harmless the EVEP Parties from and against any losses,
      damages or liabilities to which the EVEP Parties may become subject, under
      the 1933 Act or otherwise, insofar as such losses, damages or liabilities
      (or actions or claims in respect thereof) arise out of or are based upon
      (i) any untrue statement or alleged untrue statement of a material fact
      contained in the Registration Statement, the Prospectus and the Disclosure
      Package or in any amendment or supplement thereto or Blue Sky Application,
      or (ii) the omission or alleged omission to state therein a material fact
      required to be stated therein or necessary to make the statements therein,
      in light of the circumstances in which they were made, not misleading, in
      each case to the extent, but only to the extent, that such untrue
      statement or alleged untrue statement or omission or alleged omission was
      made in the Registration Statement, the Prospectus and the Disclosure
      Package or any such amendment or supplement, in reliance upon and in
      conformity with written information relating to the Underwriters furnished
      to the Partnership by the Underwriters, expressly for use in the
      preparation thereof (as provided in Section 14 hereof), and will reimburse
      the EVEP Parties for any legal or other expenses incurred by the EVEP
      Parties in connection with investigating or defending any such action or
      claim as such expenses are incurred (including such losses, damages,
      liabilities or expenses to the extent of the aggregate amount paid in
      settlement of any such action or claim, provided that (subject to Section
      7(c) hereof) any such settlement is effected with the written consent of
      the Underwriters).

            (c) Promptly after receipt by an indemnified party under Section
      8(a) or 8(b) hereof of notice of the commencement of any action, such
      indemnified party shall, if a claim in respect thereof is to be made
      against an indemnifying party under Section 8(a) or 8(b) hereof, notify
      each such indemnifying party in writing of the commencement thereof, but
      the failure so to notify such indemnifying party shall not relieve such
      indemnifying party from any liability except to the extent that it has
      been prejudiced in any material respect by such failure or from any
      liability that it may have to any such

                                       34


      indemnified party otherwise than under Section 8(a) or 8(b) hereof. In
      case any such action shall be brought against any such indemnified party
      and it shall notify each indemnifying party of the commencement thereof,
      each such indemnifying party shall be entitled to participate therein and,
      to the extent that it shall wish, jointly with any other indemnifying
      party under Section 8(a) or 8(b) hereof similarly notified, to assume the
      defense thereof, with counsel satisfactory to such indemnified party (who
      shall not, except with the consent of such indemnified party, be counsel
      to such indemnifying party), and, after notice from such indemnifying
      party to such indemnified party of its election so to assume the defense
      thereof, such indemnifying party shall not be liable to such indemnified
      party under Section 8(a) or 8(b) hereof for any legal expenses of other
      counsel or any other expenses, in each case subsequently incurred by such
      indemnified party, in connection with the defense thereof other than
      reasonable costs of investigation. The indemnified party shall have the
      right to employ its own counsel in any such action, but the fees and
      expenses of such counsel shall be at the expense of such indemnified party
      unless (i) the employment of counsel by such indemnified party at the
      expense of the indemnifying party has been authorized by the indemnifying
      party, (ii) the indemnified party shall have been advised by such counsel
      that there may be a conflict of interest between the indemnifying party
      and the indemnified party in the conduct of the defense, or certain
      aspects of the defense, of such action (in which case the indemnifying
      party shall not have the right to direct the defense of such action with
      respect to those matters or aspects of the defense on which a conflict
      exists or may exist on behalf of the indemnified party) or (iii) the
      indemnifying party shall not in fact have employed counsel reasonably
      satisfactory to such indemnified party to assume the defense of such
      action, in any of which events such fees and expenses to the extent
      applicable shall be borne, and shall be paid as incurred, by the
      indemnifying party. If at any time such indemnified party shall have
      requested such indemnifying party under Section 8(a) or 8(b) hereof to
      reimburse such indemnified party for fees and expenses of counsel, such
      indemnifying party agrees that it shall be liable for any settlement of
      the nature contemplated by Section 8(a) or 8(b) hereof effected without
      its written consent if (i) such settlement is entered into more than 60
      days after receipt by such indemnifying party of such request for
      reimbursement, (ii) such indemnifying party shall have received notice of
      the terms of such settlement at least 45 days prior to such settlement
      being entered into and (iii) such indemnifying party shall not have
      reimbursed such indemnified party in accordance with such request for
      reimbursement prior to the date of such settlement. No such indemnifying
      party shall, without the written consent of such indemnified party, effect
      the settlement or compromise of, or consent to the entry of any judgment
      with respect to, any pending or threatened action or claim in respect of
      which indemnification or contribution may be sought hereunder (whether or
      not such indemnified party is an actual or potential party to such action
      or claim) unless such settlement, compromise or judgment (A) includes an
      unconditional release of such indemnified party from all liability arising
      out of such action or claim and (B) does not include a statement as to or
      an admission of fault, culpability or a failure to act, by or on behalf of
      any such indemnified party. In no event shall such indemnifying parties be
      liable for the fees and expenses of more than one counsel, other than one
      local counsel, for all such indemnified parties in connection with any one
      action or separate but similar or related actions in the same jurisdiction
      arising out of the same general allegations or circumstances.

                                       35


            (d) If the indemnification provided for in this Section 8 is
      unavailable to or insufficient to indemnify or hold harmless an
      indemnified party under Section 8(a) or 8(b) hereof in respect of any
      losses, damages or liabilities (or actions or claims in respect thereof)
      referred to therein, then each indemnifying party under Section 8(a) or
      8(b) hereof shall contribute to the amount paid or payable by such
      indemnified party as a result of such losses, damages or liabilities (or
      actions or claims in respect thereof) in such proportion as is appropriate
      to reflect the relative benefits received by the EVEP Parties on the one
      hand, and the Underwriters on the other hand, from the offering of the
      Units. If, however, the allocation provided by the immediately preceding
      sentence is not permitted by applicable law or if the indemnified party
      failed to give the notice required under Section 8(c) hereof and such
      indemnifying party was prejudiced in a material respect by such failure,
      then each such indemnifying party shall contribute to such amount paid or
      payable by such indemnified party in such proportion as is appropriate to
      reflect not only such relative benefits but also the relative fault, as
      applicable, of the EVEP Parties on the one hand, and the Underwriters, on
      the other hand in connection with the statements or omissions that
      resulted in such losses, damages or liabilities (or actions or claims in
      respect thereof), as well as any other relevant equitable considerations.
      The relative benefits received by, as applicable, the EVEP Parties on the
      one hand and the Underwriters, on the other hand, shall be deemed to be in
      the same proportion as the total net proceeds from such offering (before
      deducting expenses) received by the EVEP Parties bear to the total
      underwriting discounts and commissions received by the Underwriters. The
      relative fault, as applicable, of the EVEP Parties, on the one hand and
      the Underwriters, on the other hand, shall be determined by reference to,
      among other things, whether the untrue or alleged untrue statement of a
      material fact or the omission or alleged omission to state a material fact
      relates to information supplied by the EVEP Parties on the one hand, or
      the Underwriters, on the other hand and the parties' relative intent,
      knowledge, access to information and opportunity to correct or prevent
      such statement or omission. The EVEP Parties and the Underwriters agree
      that it would not be just and equitable if contribution pursuant to this
      Section 8(d) were determined by pro rata allocation or by any other method
      of allocation that does not take account of the equitable considerations
      referred to above in this Section 8(d). The amount paid or payable by such
      an indemnified party as a result of the losses, damages or liabilities (or
      actions or claims in respect thereof) referred to above in this Section
      8(d) shall be deemed to include any legal or other expenses incurred by
      such indemnified party in connection with investigating or defending any
      such action or claim. Notwithstanding the provisions of this Section 8(d),
      no Underwriter shall be required to contribute any amount in excess of the
      amount by which the total price at which the Units underwritten by it and
      distributed to the public were offered to the public exceeds the amount of
      any damages that such Underwriter has otherwise been required to pay by
      reason of such untrue or alleged untrue statement or omission or alleged
      omission. No person guilty of fraudulent misrepresentation (within the
      meaning of Section 11(f) of the 1933 Act) shall be entitled to
      contribution from any person who was not guilty of such fraudulent
      misrepresentation.

            (e) The obligations of the EVEP Parties under this Section 8 shall
      be in addition to any liability that the EVEP Parties may otherwise have
      and shall extend, upon the same terms and conditions, to each officer,
      director, employee, agent or other

                                       36


      representative and to each person, if any, who controls any Underwriter
      within the meaning of the 1933 Act; and the obligations of each of the
      Underwriters under this Section 8 shall be in addition to any liability
      that the respective Underwriter may otherwise have and shall extend, upon
      the same terms and conditions, to each officer and director of the
      Partnership and General Partner who signed the Registration Statement and
      to each person, if any, who controls the EVEP Parties within the meaning
      of the 1933 Act. The obligations of each of the EnCap Entities under this
      Section 8 shall be limited to the representations and warranties of the
      EnCap Entites and the statements and information specifically concerning
      the EnCap Entities or their ownership of Sponsor Units.

      9. REPRESENTATIONS AND AGREEMENTS TO SURVIVE DELIVERY. The respective
representations, warranties, agreements and statements of the EVEP Parties and
the Underwriters, as set forth in this Agreement or made by or on behalf of
them, respectively, pursuant to this Agreement, shall remain operative and in
full force and effect regardless of any investigation (or any statement as to
the results thereof) made by or on behalf of any Underwriter or any controlling
person of any Underwriter, the EVEP Parties or any of their officers, directors
or any controlling persons and shall survive delivery of and payment for the
Units hereunder.

      10. SUBSTITUTION OF UNDERWRITERS. (a) If any Underwriter shall default in
its obligation to purchase the Units which it has agreed to purchase hereunder,
the non-defaulting Underwriters may in their discretion arrange for themselves
or another party or other parties to purchase such Units on the terms contained
herein. If within thirty-six hours after such default by any Underwriter the
non-defaulting Underwriters do not arrange for the purchase of such Units, then
the Partnership shall be entitled to a further period of thirty-six hours within
which to procure another party or parties reasonably satisfactory to the
non-defaulting Underwriters to purchase such Units on such terms. In the event
that, within the respective prescribed periods, the non-defaulting Underwriters
notify the Partnership that they have so arranged for the purchase of such
Units, or the Partnership notifies the non-defaulting Underwriters that it has
so arranged for the purchase of such Units, the non-defaulting Underwriters or
the Partnership shall have the right to postpone the Closing Date for a period
of not more than seven days, in order to effect whatever changes may thereby be
made necessary in the Registration Statement or the Prospectus, or in any other
documents or arrangements, and the Partnership agrees to file promptly any
amendments to the Registration Statement or the Prospectus which in the opinion
of the non-defaulting Underwriters may thereby be made necessary. The term
"Underwriter" as used in this Agreement shall include any persons substituted
under this Section 10 with like effect as if such person had originally been a
party to this Agreement with respect to such Units.

            (b) If, after giving effect to any arrangements for the purchase of
      the Units of a defaulting Underwriter or Underwriters made as provided in
      subsection (a) above or if no such arrangements are made, the aggregate
      number of Units which remains unpurchased does not exceed one-eleventh of
      the total Units to be sold on the Closing Date, then the Partnership shall
      have the right to require each non-defaulting Underwriter to purchase the
      Units which such Underwriter agreed to purchase hereunder and, in
      addition, to require each non-defaulting Underwriter to purchase its pro
      rata share (based on the number of Units which such Underwriter agreed to
      purchase hereunder) of the

                                       37


      Units of such defaulting Underwriter or Underwriters for which such
      arrangements have not been made.

            (c) If, after giving effect to any arrangements for the purchase of
      the Units of a defaulting Underwriter or Underwriters made by the
      non-defaulting Underwriters and the Partnership as provided in subsection
      (a) above, the number of Units which remains unpurchased exceeds
      one-eleventh of the total Units to be sold on the Closing Date, or if the
      Partnership shall not exercise the right described in subsection (b) above
      to require the non-defaulting Underwriters to purchase Units of the
      defaulting Underwriter or Underwriters, then this Agreement (or, with
      respect to the Option Closing Date, the obligations of the Underwriters to
      purchase and of the Partnership to sell the Option Units) shall thereupon
      terminate, without liability on the part of any non-defaulting Underwriter
      or the EVEP Parties except for the expenses to be borne by the Partnership
      and the Underwriters as provided in Section 12 hereof and the indemnity
      and contribution agreements in Section 8 hereof, but nothing herein shall
      relieve a defaulting Underwriter from liability for its default.

      11. TERMINATION. (a) This Agreement may be terminated by the Underwriters
at any time at or prior to the Closing Date by notice to the Partnership if any
condition specified in Section 7 hereof shall not have been satisfied on or
prior to the Closing Date. Any such termination shall be without liability of
any party to any other party except as provided in Sections 8 and 12 hereof.

            (b) This Agreement also may be terminated by the Underwriters, by
      notice to the Partnership, as to any obligation of the Underwriters to
      purchase the Option Units, if any condition specified in Section 7 hereof
      shall not have been satisfied at or prior to the Option Closing Date or as
      provided in Section 10 of this Agreement.

      If the Underwriters terminate this Agreement as provided in Sections 11(a)
or 11(b), they shall notify the Partnership by telephone or telegram, confirmed
by letter.

      12. COSTS AND EXPENSES. The Partnership will bear and pay the costs and
expenses incident to the registration of the Units and public offering thereof,
including, without limitation, (a) all expenses (including transfer taxes)
incurred in connection with the delivery to the several Underwriters of the
Units, the filing fees of the SEC, the fees and expenses of the Partnership's
counsel and accountants, (b) the preparation, printing, filing, delivery and
shipping of the Registration Statement, each Preliminary Prospectus, the
Prospectus, each Permitted Free Writing Prospectus and any amendments or
supplements thereto (except as otherwise expressly provided in Section 5(d)
hereof) and the printing, delivery and shipping of this Agreement and other
underwriting documents, including the Agreement Among Underwriters, the Selected
Dealer Agreement, Underwriters' Questionnaires and Powers of Attorney and Blue
Sky Memoranda, and any instruments or documents related to any of the foregoing,
(c) the furnishing of copies of such documents (except as otherwise expressly
provided in Section 5(d) hereof) to the Underwriters, (d) the registration or
qualification of the Units for offering and sale under the securities laws of
the various states and other jurisdictions, including the fees and disbursements
of counsel to the Underwriters relating to such registration or qualification
and in connection with preparing any Blue Sky Memoranda or related analysis, (e)
the filing fees of the NASD (if

                                       38


any) and fees and disbursements of counsel to the Underwriters relating to any
review of the offering by the NASD, (f) all printing and engraving costs related
to preparation of the certificates for the Units, including transfer agent and
registrar fees, (g) all fees and expenses relating to the authorization of the
Units for trading on the NASDAQ Global Market; (h) all travel expenses,
including air fare and accommodation expenses, of representatives of the
Partnership in connection with the offering of the Units, and (i) all of the
other costs and expenses incident to the performance by the Partnership of the
registration and offering of the Units; provided, that (except as otherwise
provided in this Section 12) the Underwriters will bear and pay all of their own
costs and expenses, including the fees and expenses of the Underwriters'
counsel, the Underwriters' transportation expenses and any advertising costs and
expenses incurred by the Underwriters incident to the public offering of the
Units.

      If this Agreement is terminated by the Underwriters in accordance with the
provisions of Section 11(a) (other than pursuant to Section 7(h)(i), (iii), (iv)
or (v)), the Partnership shall reimburse the Underwriters for all of their
reasonable out-of-pocket expenses, including the reasonable fees and
disbursements of counsel to the Underwriters.

      13. NOTICES. All notices or communications hereunder, except as herein
otherwise specifically provided, shall be in writing and if sent to the
Underwriters shall be mailed, delivered, sent by facsimile transmission, or
telegraphed and confirmed do A.G. Edwards & Sons, Inc. at One North Jefferson
Avenue, St. Louis, Missouri 63103, Attention: T. Frank Murphy, Managing
Director, Corporate Finance, facsimile number (314) 955-7387, with a copy to
Doug Kelly, Attention: General Counsel, facsimile number (314) 955-5913, or if
sent to the Partnership shall be mailed, delivered, sent by facsimile
transmission, or telegraphed and confirmed to the Partnership at EV Energy
Partners, L.P., 1001 Fannin Street, Suite 900, Houston, Texas 77002, facsimile
number (713) 659-3556 and if sent to any other party, shall be given at the
address set forth on the signature page hereof. Notice to any Underwriter
pursuant to Section 8 shall be mailed, delivered, sent by facsimile
transmission, or telegraphed and confirmed to such Underwriter's address as it
appears in the Underwriters' Questionnaire furnished in connection with the
offering of the Units or as otherwise furnished to the Partnership.

      14. INFORMATION FURNISHED BY UNDERWRITERS. The statements set forth in the
third, eleventh, twelfth, thirteenth, fourteenth and fifteenth paragraphs and
the third sentence of the sixth paragraph under the caption "Underwriting" in
the Prospectus constitute the only information furnished by or on behalf of the
Underwriters, as such information is referred to in Section 5(b) and Section 8
hereof

      15. PARTIES. This Agreement shall inure to the benefit of and be binding
upon the Underwriters, the EVEP Parties, their respective successors and assigns
and the officers, directors, employees, agents, representatives and controlling
persons referred to in Section 8 hereof (to the extent provided in Section 8)
and their respective heirs, executors, administrators, successors and assigns.
Nothing expressed or mentioned in this Agreement is intended or shall be
construed to give any person, corporation or other entity any legal or equitable
right, remedy or claim under or in respect of this Agreement or any provision
herein contained; this Agreement and all conditions and provisions hereof being
intended to be and being for the sole and exclusive benefit of the parties
hereto and their respective successors and assigns and said

                                       39


controlling persons and said officers and directors, and for the benefit of no
other person, corporation or other entity. No purchaser of any of the Units from
any Underwriter shall be construed a successor or assign by reason merely of
such purchase.

      16. RESEARCH INDEPENDENCE. In addition, the Partnership acknowledges that
the Underwriters' research analysts and research departments are required to be
independent from their respective investment banking divisions and are subject
to certain regulations and internal policies, and that such Underwriters'
research analysts may hold and make statements or investment recommendations
and/or publish research reports with respect to the Partnership and/or the
offering that differ from the views of its investment bankers. The Partnership
hereby waives and releases, to the fullest extent permitted by law, any claims
that the Partnership may have against the Underwriters with respect to any
conflict of interest that may arise from the fact that the views expressed by
their independent research analysts and research departments may be different
from or inconsistent with the views or advice communicated to the Partnership by
such Underwriters' investment banking divisions. The Partnership acknowledges
that each of the Underwriters is a full service securities firm and as such from
time to time, subject to applicable securities laws, may effect transactions for
its own account or the account of its customers and hold long or short positions
in debt or equity securities of the companies which may be the subject of the
transactions contemplated by this Agreement.

      17. NO FIDUCIARY DUTY. Notwithstanding any preexisting relationship,
advisory or otherwise, between the parties or any oral representations or
assurances previously or subsequently made by the Underwriters, the Partnership
acknowledges and agrees that: (i) nothing herein shall create a fiduciary or
agency relationship between the Partnership, on the one hand, and the
Underwriters, on the other; (ii) the Underwriters are not acting as advisors,
expert or otherwise, to the Partnership in connection with this offering, the
sale of the Units or any other services the Underwriters may be deemed to be
providing hereunder, including, without limitation, with respect to the public
offering price of the Units; (iii) the relationship between the Partnership, on
the one hand, and the Underwriters, on the other, is entirely and solely
commercial, based on arms-length negotiations; (iv) any duties and obligations
that the Underwriters may have to the Partnership shall be limited to those
duties and obligations specifically stated herein; and (v) notwithstanding
anything in this Agreement to the contrary, the Partnership acknowledges that
the Underwriters' may have financial interest in the success of the offering
that are not limited to the difference between the price to the public and the
purchase price paid to the Partnership by the Underwriters for the Units and the
Underwriters have no obligation to disclose, or account to the Partnership for,
any of such additional financial interests. The Partnership hereby waives and
releases, to the fullest extent permitted by law, any claims that the
Partnership may have against the Underwriters with respect to any breach or
alleged breach of fiduciary duty with respect to the transactions contemplated
by this Agreement.

      18. COUNTERPARTS. This Agreement may be executed by any one or more of the
parties hereto in any number of counterparts, each of which shall be deemed to
be an original, but all such counterparts shall together constitute one and the
same instrument.

      19. PRONOUNS. Whenever a pronoun of any gender or number is used herein,
it shall, where appropriate, be deemed to include any other gender and number.

                                       40


      20. TIME OF ESSENCE. Time shall be of the essence of this Agreement.

      21. APPLICABLE LAW. This Agreement shall be governed by, and construed in
accordance with, the laws of the State of Missouri, without giving effect to the
choice of law or conflict of laws principles thereof.

                                       41


         If the foregoing is in accordance with your understanding, please so
indicate in the space provided below for that purpose, whereupon this letter
shall constitute a binding agreement among the EVEP Parties and the
Underwriters.

                               EV ENERGY PARTNERS, L.P.

                               By: EV Energy GP, L.P., its General Partner

                               By: EV Management, LLC, its General Partner

                               By:    /s/ Michael E. Mercer
                                  --------------------------------------------
                                   Michael E. Mercer
                                   Senior Vice President and
                                   Chief Financial Officer

                               EV ENERGY GP, L.P.

                               By: EV Management, LLC, its General Partner

                               By:    /s/ Michael E. Mercer
                                  --------------------------------------------
                                   Michael E. Mercer
                                   Senior Vice President and
                                   Chief Financial Officer

                               EV MANAGEMENT, LLC

                               By:    /s/ Michael E. Mercer
                                  --------------------------------------------
                                   Michael E. Mercer
                                   Senior Vice President and
                                   Chief Financial Officer

                               EV PROPERTIES GP, LLC

                               By:    /s/ Mark A. Houser
                                  ------------------------------------------
                                   Mark A. Houser
                                   Executive Vice President and
                                   Chief Operating Officer

                   [Signature Page to Underwriting Agreement]



                               EV PROPERTIES, L.P.

                               By: EV Properties GP, LLC, its General Partner

                               By: EnerVest Management Partners, Ltd.,
                                   a Texas limited partnership,
                                   its sole Member

                               By: EnerVest Management GP, L.C.,
                                   a Texas limited liability company,
                                   its General Partner

                               By:    /s/ Mark A. Houser
                                  ------------------------------------------
                                   Mark A. Houser
                                   Executive Vice President and
                                   Chief Operating Officer

                               EVEC HOLDINGS, LLC

                               By:    /s/ Mark A. Houser
                                  ------------------------------------------
                                   Mark A. Houser
                                   Executive Vice President and
                                   Chief Operating Officer

                               ENERVEST MANAGEMENT PARTNERS, LTD.

                               By: EnerVest Management GP, L.C.,
                                   a Texas limited liability company,
                                   its General Partner

                               By:    /s/ Mark A. Houser
                                  ------------------------------------------
                                   Mark A. Houser
                                   Executive Vice President and
                                   Chief Operating Officer

                               CGAS HOLDINGS, LLC

                               By:    /s/ Mark A. Houser
                                  ------------------------------------------
                                   Mark A. Houser
                                   President and Chief Operating Officer

                   [Signature Page to Underwriting Agreement]



                               ENCAP ENERGY CAPITAL FUND V, L.P.

                               By:    EnCap Equity Fund V GP, L.P., a Texas
                                      limited partnership, its General Partner

                               By:    EnCap Investments LP, a Delaware limited
                                      partnership, its General Partner

                               By:    EnCap Investments GP, L.L.C., a Delaware
                                      limited liability company, its General
                                      Partner

                               By:        /s/ Gary R. Petersen
                                    -----------------------------------------
                               Name:      Gary R. Petersen
                               Title:     Senior Managing Director

                               ENCAP V-B ACQUISITIONS, L.P.

                               By:    EnCap V-B Acquisitions GP, LLC, a Delaware
                                      limited liability company, its General
                                      Partner

                               By:    EnCap Energy Capital Fund V-B, L.P. a
                                      Texas limited partnership, its General
                                      Partner

                               By:    EnCap Equity Fund V GP, L.P., a Texas
                                      limited partnership, its General Partner

                               By:    EnCap Investments LP, a Delaware limited
                                      partnership, its General Partner

                               By:    EnCap Investments GP, L.L.C., a Delaware
                                      limited liability company, its General
                                      Partner

                               By:        /s/ Gary R. Petersen
                                    -----------------------------------------
                               Name:      Gary R. Petersen
                               Title:     Senior Managing Director

                   [Signature Page to Underwriting Agreement]



ACCEPTED in St. Louis, Missouri,
as of the date first above written.

A.G. EDWARDS & SONS, INC.
RAYMOND JAMES & ASSOCIATES, INC.
WACHOVIA CAPITAL MARKETS, LLC
OPPENHEIMER & CO. INC.

By:   A.G. EDWARDS & SONS, INC.

By:
      ________________________________
      Name:
      Title:

                   [Signature Page to Underwriting Agreement]



                                   SCHEDULE I

                              ALLOCATION OF UNITS


                       NAME                             NUMBER OF UNITS
- ---------------------------------------------------     ---------------
                                                     
A.G. Edwards & Sons, Inc............................        1,560,000
Raymond James & Associates, Inc.....................        1,365,000
Wachovia Capital Markets, LLC.......................          682,500
Oppenheimer & Co. Inc...............................          292,500
                                                            ---------
         Total......................................        3,900,000
                                                            =========


                                   Schedule I



                                  SCHEDULE II

                             FOREIGN QUALIFICATIONS



          ENTITY:                         FOREIGN QUALIFICATIONS:
- -----------------------------------       ------------------------
                                       
EV Management, LLC                          Texas

EV Energy GP, L.P.                          Texas

EV Energy Partners, L.P.                    Texas

EV Properties GP, LLC                       None

EV Properties, L.P.                         None

EVPP GP LLC                                 None

EnerVest Production Partners, L.P.          Louisiana

EVWV GP LLC                                 None

EnerVest WV, LP                             West Virginia and Pennsylvania

EVCG GP LLC                                 Ohio

CGAS Properties, L.P.                       Ohio

EnerVest-Cargas, Ltd.                       Louisiana

Lower Cargas Operating Company LLC          None


                                  Schedule II



                                  SCHEDULE III

                       PERMITTED FREE WRITING PROSPECTUS

1.  Electronic Road Show on Netroadshow.com

                                  Schedule III



                                   EXHIBIT A

                        OPINION OF HAYNES AND BOONE, LLP

      1.Formation and Due Qualification. Each of the Partnership Entities has
been duly formed or incorporated and is validly existing as a limited
partnership, limited liability company, as the case may be, in good standing
under the laws of its respective jurisdiction of formation or incorporation, and
is, or at the Closing Date will be, duly registered or qualified to do business
and is in good standing as a foreign limited partnership or foreign limited
liability company, as the case may be, in each jurisdiction, as set forth under
its name on Schedule II of the Agreement, in which its ownership or lease of
property or the conduct of its businesses requires such registration or
qualification, except where the failure so to register or qualify would not (i)
have a material adverse effect on the consolidated financial position, partners'
or members' equity, results of operations, business or prospects of the
Partnership Entities taken as a whole or (ii) subject the limited partners of
the Partnership to any material liability or disability. Each of the Partnership
Entities has all limited partnership or limited liability company, as the case
may be, power and authority necessary to own or lease its properties currently
owned or leased or to be owned or leased at the Closing Date, to assume the
liabilities assumed or being assumed by it pursuant to the Transaction Documents
and to conduct its business as currently conducted and as to be conducted at the
Closing Date, in each case in all material respects as described in the
Prospectus.

      2.Ownership of the General Partner Interest in the Partnership. At the
Closing Date and, if applicable, the Option Closing Date, after giving effect to
the Transactions, the General Partner will be the sole general partner of the
Partnership with a 2% general partner interest in the Partnership. Such general
partner interest will be duly authorized and validly issued in accordance with
the Partnership Agreement and will be fully paid (to the extent required under
the Partnership Agreement) and nonassessable (except as such nonassessability
may be affected by Section 17-303 and 17-607 of the Delaware LP Act, and the
General Partner will own such general partner interest free and clear of all
liens, encumbrances (except restrictions on transferability described in the
Prospectus or the Partnership Agreement), security interests, equities, charges
or claims (i) in respect of which a financing statement under the Uniform
Commercial Code of the State of Delaware naming the General Partner as debtor is
on file as of a recent date in the office of the Secretary of State of the State
of Delaware or (ii) otherwise known to such counsel, without independent
investigation, other than those created by or arising under the Delaware LP Act,
contained in the Partnership Agreement or described in the Prospectus.

      3.Ownership of Sponsor Units and the Incentive Distribution Rights. All of
the Sponsor Units and Incentive Distribution Rights and the limited partner
interests represented thereby are duly authorized and validly issued in
accordance with the Partnership Agreement, and are fully paid (to the extent
required under the Partnership Agreement) and nonassessable (except as such
nonassessability may be affected by Sections 17-303 and 17-607 of the Delaware
LP Act and as otherwise described in the Prospectus under the caption "The
Partnership Agreement -- Limited Liability," "Risk Factors -- Risks Inherent in
an Investment in Us -- Your liability may not be limited if a court finds that
unitholder action constitutes control of our business" and "Risk Factors --
Risks Inherent in an Investment in Us -- Unitholders may have

                               Exhibit A - Page 1



liability to repay distributions that were wrongfully distributed to them"). EVH
owns 163,625 Common Units and 810,030 Subordinated Units, EV Investors owns
155,000 Subordinated Units, CGH owns 343,255 Common Units and 1,698,800
Subordinated Units, and the EnCap Entities own an aggregate of 88,120 Common
Units and 436,170 Subordinated Units as described in the Prospectus and the
General Partner owns all of the Incentive Distribution Rights. EVH, EV
Investors, CGH and the EnCap Entities own their respective Sponsor Units and the
General Partner owns the Incentive Distribution Rights free and clear of all
liens, encumbrances (except restrictions on transferability as described in the
Prospectus or contained in the Partnership Agreement), security interests,
equities, charges or claims (i) in respect of which a financing statement under
the Uniform Commercial Code of the State of Delaware naming any of them as
debtor is on file as of a recent date in the office of the Secretary of State of
the State of Delaware or (ii) otherwise known to such counsel, without
independent investigation, other than those created by or arising under the
Delaware LP Act, contained in the Partnership Agreement or described in the
Prospectus.

      4.Valid Issuance of the Units. The Units to be issued and sold to the
Underwriters by the Partnership pursuant to this Agreement and the limited
partner interests represented thereby have been duly authorized by the
Partnership Agreement and, when issued and delivered to the Underwriters against
payment therefor in accordance with the terms hereof will be validly issued,
fully paid (to the extent required under the Partnership Agreement) and
nonassessable (except as such nonassessability may be affected by Sections
17-303 and 17-607 of the Delaware LP Act and as otherwise described in the
Prospectus under the caption "The Partnership Agreement -- Limited Liability,"
"Risk Factors -- Risks Inherent in an Investment in Us -- Your liability may not
be limited if a court finds that unitholder action constitutes control of our
business" and "Risk Factors -- Risks Inherent in an Investment in Us --
Unitholders may have liability to repay distributions that were wrongfully
distributed to them"); and other than the Sponsor Units and the Incentive
Distribution Rights, the Units will be the only limited partner interests of the
Partnership issued and outstanding at the date of such opinion.

      5.Ownership of Partnership Interests in the General Partner. The GP LLC
owns 100% of the outstanding general partner interests in the General Partner
and EVMP, the EnCap Entities and EV Investors own collectively 100% of the
outstanding limited partner interests in the General Partner and all of such
interests have been duly authorized and validly issued in accordance with the
General Partnership Agreement and are fully paid (to the extent required under
the General Partner LP Agreement) and nonassessable (except as such
nonassessability may be affected by Section 17-303 and 17-607 of the Delaware LP
Act). GP LLC, EVMP, the EnCap Entities and EV Investors own such interests free
and clear of all liens, encumbrances, security interests, equities, charges or
claims (i) in respect of which a financing statement under the Uniform
Commercial Code of the State of Delaware naming any of them as debtor is on file
as of a recent date in the office of the Secretary of State of the State of
Delaware or (ii) otherwise known to such counsel, without independent
investigation, other than those created by or arising under the Delaware LP Act,
contained in the General Partnership Agreement or described in the Prospectus.

      6.Ownership of Limited Liability Company Interests in the GP LLC. The
outstanding limited liability company interests in GP LLC owned by EVMP comprise
all of the limited liability company interests in GP LLC and all of such
interests have been authorized and

                               Exhibit A - Page 2



validly issued in accordance with the GP LLC LLC Agreement. Such outstanding
limited liability company interests are fully paid (to the extent required under
the GP LLC LLC Agreement) and nonassessable (except as such nonassessability may
be affected by Section 18-607 of the Delaware LLC Act), and EVMP owns such
interests free and clear of all liens, encumbrances, security interests,
equities, charges or claims (i) in respect of which a financing statement under
the Uniform Commercial Code of the State of Delaware naming any of them as
debtor is on file as of a recent date in the office of the Secretary of State of
the State of Delaware or (ii) otherwise known to such counsel, without
independent investigation, other than those created by or arising under the
Delaware LLC Act, the GP LLC LLC Agreement or described in the Prospectus.

      7.Ownership of Partnership Interests in the Operating Partnership.
Operating Partnership GP owns 100% of the outstanding general partner interests
in the Operating Partnership and the Partnership owns 100% of the outstanding
limited partner interests in the Operating Partnership. All of such interests
have been duly authorized and validly issued in accordance with the Operating
Partnership LP Agreement and have been fully paid (to the extent required under
the Operating Partnership LP Agreement) and nonassessable (except as such
nonassessability may be affected by Section 17-303 and 17-607 of the Delaware LP
Act), and Operating Partnership GP and the Partnership will own such interests
free and clear of all liens, encumbrances, security interests, equities, charges
or claims (i) in respect of which a financing statement under the Uniform
Commercial Code of the State of Delaware naming any of them as debtor is on file
as of a recent date in the office of the Secretary of State of the State of
Delaware or (ii) otherwise known to such counsel, without independent
investigation, other than those created by or arising under the Delaware LP Act,
contained in the Operating Partnership LP Agreement or securing indebtedness
under the Credit Facility.

      8.Ownership of Limited Liability Company Interests in the Operating
Partnership GP. The Partnership owns 100% of the outstanding limited liability
company interests in the Operating Partnership GP and all of such interests have
been authorized and validly issued in accordance with the Operating Partnership
GP LLC Agreement. and are fully paid (to the extent required under the Operating
Partnership GP LLC Agreement) and nonassessable (except as such nonassessability
may be affected by Section 18-607 of the Delaware LLC Act), and the Partnership
owns such interests free and clear of all liens, encumbrances, security
interests, equities, charges or claims (i) in respect of which a financing
statement under the Uniform Commercial Code of the State of Delaware naming any
of them as debtor is on file as of a recent date in the office of the Secretary
of State of the State of Delaware or (ii) otherwise known to such counsel,
without independent investigation, other than those created by or arising under
the Delaware LLC Act, contained in the Operating Partnership GP LLC Agreement or
securing indebtedness under the Credit Facility.

      9.Ownership of the Subsidiaries. The Partnership owns, directly or
indirectly, 100% of the limited liability company interests or partnership
interests, as the case may be, in the Subsidiaries, such interests have been
duly authorized and validly issued in accordance with the limited liability
company or limited partnership agreement, as the case may be, of the respective
Subsidiaries, and are fully paid (to the extent required under their respective
limited liability company agreement or limited partnership agreement) and
non-assessable (except as such nonassessability may be affected by Section
18-607 of the Delaware LLC Act, in the case of a

                               Exhibit A - Page 3



Delaware limited liability company, or Section 17-607 of the Delaware LP Act, in
the case of a Delaware limited partnership), in each case, free and clear of all
liens, encumbrances, security interests, equities, charges and other claims (i)
in respect of which a financing statement under the Uniform Commercial Code of
the State of Delaware naming any of them as debtor is on file as of a recent
date in the office of the Secretary of State of the State of Delaware or (ii)
otherwise known to such counsel, without independent investigation, other than
those created by or arising under the Delaware LP Act or securing indebtedness
under the Credit Facility.

      10.No Preemptive Rights, Registration Rights or Options. Except as
described in the Registration Statement, the Prospectus and the Disclosure
Package, there are no options, warrants, preemptive rights or other rights to
subscribe for or to purchase, nor any restriction upon the voting or transfer
of, any partnership or limited liability company interests in any Partnership
Entity pursuant to any partnership agreement, limited liability company
agreement, certificate of formation or conversion or other constituent document
of any Partnership Entity or any other agreement or instrument listed as an
exhibit to the Registration Statement. To the knowledge of such counsel, neither
the filing of the Registration Statement nor the offering or sale of the Units
as contemplated by this Agreement gives rise to any rights for or relating to
the registration of any Units or other securities of any Partnership Entity
other than as described in the Prospectus, as provided in the Partnership
Agreement or as have been waived.

      11.Authority and Authorization. The Partnership has all requisite
partnership power and authority to issue, sell and deliver (i) the Units, in
accordance with and upon the terms and conditions set forth in this Agreement
and the Partnership Agreement and (ii) the Sponsor Units and Incentive
Distribution Rights, in accordance with and upon the terms and conditions set
forth in the Transaction Documents, the Registration Statement, the Prospectus,
the Disclosure Package and the Partnership Agreement.

      12.Due Authorization, Execution and Delivery of Agreement. This Agreement
has been duly authorized, executed and delivered by each of the Partnership, the
General Partner, GP LLC, the Operating Partnership and the Operating Partnership
GP.

      13.Enforceability of Other Agreements. Each of the Operative Agreements to
which any of the Partnership Entities is a party has been duly authorized and
validly executed and delivered by each of the Partnership Entities party
thereto. Each of the Operative Agreements governed by Delaware law constitutes a
valid and legally binding agreement of the Partnership Entities party thereto,
enforceable against each of them in accordance with its respective terms,
subject to (i) applicable bankruptcy, insolvency, fraudulent transfer,
reorganization, moratorium and similar laws relating to or affecting creditors'
rights generally and by general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law) and (ii)
public policy, federal and state securities laws and other applicable laws
relating to fiduciary duties and indemnification and an implied covenant of good
faith and fair dealing.

      14.No Conflicts. None of the offering, issuance and sale by the
Partnership of the Units, the execution, delivery and performance of this
Agreement or the Operative Agreements by the Partnership Entities that are
parties hereto or thereto, or the consummation of the transactions contemplated
hereby and thereby (including the Transactions) constitutes a breach or
violation of or a default (or an event which, with notice or lapse of time or
both, would

                               Exhibit A - Page 4



constitute such a default) under, or results or will result in the
creation or imposition of any lien, charge or encumbrance upon any property or
assets of any of the Partnership Entities pursuant to, (i) the partnership
agreement, limited liability company agreement, certificate of formation,
certificate or articles of incorporation, bylaws or other constituent document
of any of the Partnership Entities, (ii) (A) any Transaction Document, (B) any
agreement or other instrument filed as an exhibit to the Registration Statement
or (C) any indenture or loan agreement to which the Partnership is a party or by
which any of their properties may be bound or any other agreement that has been
identified to such counsel as being material to the Partnership, (iii) the
Delaware LP Act, the Delaware LLC Act, the Delaware General Corporation Law (the
"DGCL"), the laws of the State of Texas or federal law or (iv) any order,
judgment, decree or injunction of any court or governmental agency or body known
to such counsel directed to any of the Partnership Entities or any of their
properties in a proceeding to which any of them or their property is a party,
which conflict, breach, violation, default or lien in the case of clauses (ii),
(iii) or (iv), would reasonably be expected to have a Material Adverse Effect or
a material adverse effect on the ability of any of the Partnership Entities to
consummate the transactions (including the Transactions) provided for in this
Agreement or the Operative Agreements; provided, however, that no opinion is
expressed pursuant to this paragraph with respect to federal or state securities
laws and other anti-fraud laws.

      15.Consents. No permit, consent, approval, authorization, order,
registration, filing or qualification ("consent") under the Delaware LP Act, the
Delaware LLC Act, the DGCL, Texas law or federal law is required in connection
with the offering, issuance and sale by the Partnership of the Units, the
execution, delivery and performance of this Agreement and the Operative
Agreements by the Partnership Entities party hereto and thereto or the
consummation by the Partnership Entities of the transactions contemplated hereby
and thereby (including the Transactions), except (i) for such consents required
under the 1933 Act, the 1934 Act and under state securities or "Blue Sky" laws,
as to which such counsel need not express any opinion, (ii) for such consents
that have been obtained or made, (iii) for such consents that (A) are of a
routine or administrative nature, (B) are not customarily obtained or made prior
to the consummation of transactions such as those contemplated by this Agreement
or the Operative Agreements and (C) are expected in the reasonable judgment of
the General Partner to be obtained or made in the ordinary course of business
subsequent to the consummation of the Transactions (other than those
contemplated by the Credit Facility), (iv) for such consents which, if not
obtained or made, would not, individually or in the aggregate, have a Material
Adverse Effect, (v) as disclosed in the Prospectus and the Disclosure Package or
(vi) approval of the underwriting terms by the NASD.

      16.Accuracy of Statements. The statements set forth in the Registration
Statement, the Preliminary Prospectus, the Prospectus and any Permitted Free
Writing Prospectuses under the captions "How We Will Make Cash Distributions,"
"Business -- Regulation," "Business -- Environmental Matters," "Certain
Relationships and Related Party Transactions," "Conflicts of Interest and
Fiduciary Duties," "Description of the Common Units," "The Partnership
Agreement" and "Investment in Us by Employee Benefit Plans," insofar as they
describe any agreement, statute or regulation or refer to statements of law or
legal conclusions, are accurate and complete in all material respects; and the
Common Units, the Subordinated Units and the Incentive Distribution Rights
conform in all material respects to the descriptions thereof contained in the
Registration Statement and Prospectus under the captions "Summary -- The

                               Exhibit A - Page 5



Offering," "How We Will Make Cash Distributions," "Description of the Common
Units," and "The Partnership Agreement."

      17.Tax Opinion. The opinion of Haynes and Boone, LLP that is filed as
Exhibit 8.1 to the Registration Statement is confirmed, and the Underwriters may
rely upon such opinion as if it were addressed to them.

      18.Effectiveness of Registration Statement. The Registration Statement was
declared effective under the 1933 Act on September 25, 2006; to the knowledge of
such counsel, no stop order suspending the effectiveness of the Registration
Statement has been issued and no proceedings for that purpose have been
instituted or threatened by the Commission; and any required filing of the
Prospectus pursuant to Rule 424(b) has been made in the manner and within the
time period required by such Rule.

      19.Compliance as to Form. Except for the financial statements and the
notes and schedules thereto, and the other financial, statistical and accounting
data included in the Registration Statement, as to which such counsel need not
express any opinion, the Registration Statement, on the Effective Date and on
the applicable Closing Date, the Preliminary Prospectus, the Prospectus, when
filed with the SEC pursuant to Rule 424(b) and on the applicable Closing Date
(except for the financial statements and the notes and the schedules thereto,
and the other financial, statistical and accounting data included or
incorporated by reference in the Registration Statement or the Prospectus, as to
which such counsel need not express any opinion) and the Permitted Free Writing
Prospectuses appear on their face to comply in all material respects with the
requirements of the 1933 Act and the 1933 Act Rules and Regulations.

      20.Investment Company Act of 1940, as amended. None of the Partnership
Entities is an "investment company," within the meaning of the Investment
Company Act of 1940, as amended.

      21.Legal Proceedings or Contracts to be Described or Filed. To the
knowledge of such counsel, (i) there are no legal or governmental proceedings
pending or threatened to which any of the Partnership Entities is a party or to
which any of their respective properties is subject that are required to be
described in the Preliminary Prospectus and the Prospectus but are not so
described as required and (ii) there are no agreements, contracts, indentures,
leases or other instruments that are required to be described in the Preliminary
Prospectus and the Prospectus or to be filed as exhibits to the Registration
Statement that are not described or filed as required by the 1933 Act or the
1933 Act Rules and Regulations.

      In addition, such counsel shall state that they have participated in
conferences with officers and other representatives of the Partnership Entities,
the independent public accountants of the Partnership, and representatives of
the Underwriters, at which the contents of the Registration Statement, the
Disclosure Package, the Preliminary Prospectus and the Prospectus and related
matters were discussed, and although such counsel has not independently
verified, is not passing on, and is not assuming any responsibility for the
accuracy, completeness or fairness of the statements contained in, the
Registration Statement, the Disclosure Package, the Preliminary Prospectus and
the Prospectus (except to the extent specified in the foregoing

                               Exhibit A - Page 6



opinion), based on the foregoing, no facts have come to such counsel's attention
that lead such counsel to believe that:

      (A).the Registration Statement at the time it became effective contained
an untrue statement of a material fact or omitted to state a material fact
required to be stated therein or necessary to make the statements therein not
misleading,

      (B).the Prospectus as of its issue date and the Closing Date contained or
contains an untrue statement of a material fact or omitted or omits to state a
material fact necessary to make the statements therein, in the light of the
circumstances under which they were made, not misleading, or

      (C).the Disclosure Package (other than a road show or bona fide electronic
road show as defined in Rule 433 of the Exchange Act), as of the Execution Time,
contained any untrue statement of a material fact or omitted to state any
material fact necessary in order to make the statements therein, in light of the
circumstances under which they were made, not misleading,

      other than in the case of (A), (B) and (C) above as applicable (i) the
financial statements included therein, including the notes and schedules there
to and the auditors' reports thereon, and (ii) the other financial statistical
data included therein, as to which such counsel need not comment.

In rendering such opinion, such counsel may (i) rely in respect of matters of
fact upon certificates of officers and employees of the Partnership Entities and
upon information obtained from public officials, (ii) assume that all documents
submitted to them as originals are authentic, that all copies submitted to them
conform to the originals thereof, and that the signatures on all documents
examined by them are genuine, (iii) state that their opinion is limited to
federal laws, the Delaware LP Act, the Delaware LLC Act, the DGCL and Texas law,
(iv) state that they express no opinion with respect to the title of any of the
Partnership Entities to any of their respective real or personal property
purported to be transferred by the Contribution Documents nor with respect to
the accuracy or descriptions of real or personal property, and (v) state that
they express no opinion with respect to state or local taxes or tax statutes to
which any of the limited partners of the Partnership or any of the Partnership
Entities may be subject.

                               Exhibit A - Page 7



                                   EXHIBIT B

             [OHIO][WEST VIRGINIA][LOUISIANA] LOCAL COUNSEL OPINION

      1.Due Qualification. Each of the [applicable Partnership Entities] has
been duly qualified or registered as a foreign limited partnership or foreign
limited liability company, as the case may be, for the transaction of business
under the laws of the State of [Ohio][West Virginia][Louisiana].

      2.Power and Authority. Each of the Partnership Entities has all limited
partnership or limited liability company, as applicable, power and authority
under the laws of the State of [Ohio][West Virginia][Louisiana] necessary to own
or lease its properties and to conduct its business in the State of [Ohio][West
Virginia][Louisiana], in each case in all material respects as described in the
Prospectus.

      3.Limited Liability. Upon the consummation of the Transactions, as a
result solely of their ownership interests in the Partnership or the
Subsidiaries, as applicable, the Partnership will not be liable under the laws
of the State of [Ohio][West Virginia][Louisiana] for the liabilities of the
Subsidiaries, and the Unitholders will not be liable under the laws of the State
of [Ohio][West Virginia][Louisiana] for the liabilities of the Partnership or
the Subsidiaries, except in each case to the same extent as under the laws of
the State of Delaware.

      4.No Consents. No permit, consent, approval, authorization, order,
registration, filing or qualification ("consent") of or with any court,
governmental agency or body of the State of [Ohio][West Virginia][Louisiana]
having jurisdiction over any of the Partnership Entities or any of their
respective properties is required for the issuance and sale of the Units by the
Partnership, the execution, delivery and performance of this Agreement and the
Operative Agreements by the Partnership Entities party hereto and thereto or the
consummation by the Partnership Entities of the transactions contemplated hereby
and thereby (including the Transactions), except (i) for such consents required
under state securities or "Blue Sky" laws in connection with the purchase and
distribution of the Units by the Underwriters, as to which such counsel need not
express any opinion, (ii) for such consents that have been obtained or made,
(iii) for such consents which, if not obtained or made, would not, individually
or in the aggregate, have a material adverse effect upon the operations
conducted or to be conducted as described in the Prospectus in the State of
[Ohio][West Virginia][Louisiana] by the Partnership Entities or (iv) as
disclosed in the Prospectus.

      5.No Conflicts. None of the offering, issuance and sale by the Partnership
of the Units, the execution, delivery and performance of this Agreement or the
Operative Agreements by the Partnership Entities that are parties hereto or
thereto, or the consummation of the transactions contemplated hereby and thereby
(including the Transactions) (i) violates or will violate any statute of the
State of [Ohio][West Virginia][Louisiana] or any rule, regulation or, to such
counsel's knowledge after due inquiry, any order of any agency of the State of
[Ohio][West Virginia][Louisiana] having jurisdiction over any of the Partnership
Entities or any of their respective properties or (ii) results or will result in
the creation or imposition of any lien, charge or encumbrance upon any property
or assets of the Partnership Entities in the State of [Ohio][West
Virginia][Louisiana] (other than liens created pursuant to the Credit Facility),
which

                               Exhibit B - Page 1



violation or lien would have a material adverse effect on the Unitholders
or the operations conducted or to be conducted as described in the Prospectus
and the Disclosure Package in the State of [Ohio][West Virginia][Louisiana] by
the Partnership Entities.

      6.Enforceability of Transaction Documents. Each of the Transaction
Documents (i) governed by [Ohio][West Virginia][Louisiana] law or (ii) relating
to the transfer of property in the State of [Ohio][West Virginia][Louisiana] (if
governed by laws other than [Ohio][West Virginia][Louisiana], to the extent it
is a valid and legally binding agreement under the applicable law as stated
therein and that such law applies thereto), constitutes a valid and legally
binding agreement of the parties thereto under the laws of the State of
[Ohio][West Virginia][Louisiana], enforceable against such parties in accordance
with their respective terms, subject to (i) applicable bankruptcy, insolvency,
fraudulent transfer, reorganization, moratorium and similar laws relating to or
affecting creditors' rights generally and by general principles of equity
(regardless of whether such enforceability is considered in a proceeding in
equity or at law) and (ii) public policy, applicable law relating to fiduciary
duties and indemnification and an implied covenant of good faith and fair
dealing.

      7.Sufficiency of Contribution Documents. Each of the Contribution
Documents is in a form legally sufficient as between the parties thereto to
convey to the transferee or successor, as the case may be, thereunder all right,
title and interest of the transferor or predecessor, as the case may be, stated
therein in and to the properties located in the State of [Ohio][West
Virginia][Louisiana] as described in the Contribution Documents, subject to the
conditions, reservations and limitations contained in the Contribution
Documents, except motor vehicles and other property requiring conveyance of
certificated title, as to which the Contribution Documents are legally
sufficient to compel delivery of such certificated title.

      8.Form of Deeds and Assignments. Each of the Contribution Documents that
are deeds or real property assignments (including, without limitation, the form
of the exhibits and schedules thereto) is in a form legally sufficient for
recordation in the appropriate public offices of the State of [Ohio][West
Virginia][Louisiana], to the extent such recordation is required to evidence
title to the properties covered thereby in the transferee or successor, as the
case may be, thereunder, and, upon proper recordation of any of such deeds, real
property assignments, as the case may be, in the State of [Ohio][West
Virginia][Louisiana], will constitute notice to all third parties under the
recordation statutes of the State of [Ohio][West Virginia][Louisiana] concerning
record title to the assets transferred thereby; recordation in the office of the
[insert applicable office] for each county in which any Partnership Entity owns
property is the appropriate public office in the State of [Ohio][West
Virginia][Louisiana] for the recordation of deeds and assignments of interests
in real property located in such county.

      9.Permits. To such counsel's knowledge after due inquiry, each of the
Partnership Entities has such permits, consents, licenses, franchises,
certificates and authorizations of governmental or regulatory authorities
("permits") of the State of [Ohio][West Virginia][Louisiana] as are necessary to
own its properties and to conduct its business in the manner described in the
Prospectus and the Disclosure Package, subject to such qualifications as may be
set forth in the Prospectus and the Disclosure Package and except for such
permits that, if not obtained, would not, individually or in the aggregate, have
a material adverse effect upon the

                               Exhibit B - Page 2



operations conducted or to be conducted as described in the Prospectus and the
Disclosure Package in the State of [Ohio][West Virginia][Louisiana] by the
Partnership Entities.

      In rendering such opinions, such counsel may (i) rely in respect of
matters of fact upon certificates of officers and employees of the Partnership
Entities and upon information obtained from public officials, (ii) assume that
all documents submitted to such counsel as originals are authentic, and all
copies submitted to such counsel conform to the originals thereof, and that the
signatures on all documents examined by such counsel are genuine, (iii) state
that their opinion is limited to the laws of the State of [Ohio][West
Virginia][Louisiana] and (iv) state that they express no opinion with respect to
state or local taxes or tax statutes to which any of the limited partners of the
Partnership or the Partnership Entities may be subject.

                               Exhibit B - Page 3



                                   EXHIBIT C

                                 COMFORT LETTER

September __, 2006

A.G. Edwards & Sons, Inc.
Raymond James & Associates, Inc.
Wachovia Capital Markets, LLC
Oppenheimer & Company, Inc.
c/o A.G. Edwards & Sons, Inc.
One North Jefferson Avenue
St. Louis, Missouri 63103

As Initial Purchasers of 3,900,000 common units of EV Energy Partners, L.P.

Dear Sirs:

We have audited the combined balance sheets of the Combined Predecessor Entities
(the "Company"), as defined in Note 1 to the combined financial statements, as
of December 31, 2005 and 2004, and the combined statements of operations and
comprehensive income, cash flows and changes in owners' equity for each of the
three years in the period ended December 31, 2005. We have audited the balance
sheet of EV Energy Partners, L.P. and the balance sheet of EV Energy GP, L.P.,
each as of May 12, 2006. All of the audited financial statements are included in
Registration Statement No. 333-134139 on Form S-1 filed by EV Energy Partners,
L.P. under the Securities Act of 1933 (the "Act"); our reports with respect
thereto (which report for the Company expresses an unqualified opinion and
includes an explanatory paragraph that indicates that the combined financial
statements have been restated as disclosed in footnote 16 to the combined
financial statements) are also included in that registration statement. This
registration statement, dated September __, 2006, is herein referred to as the
registration statement.

In connection with the registration statement  --

1.    We are an independent registered public accounting firm with respect to
      the Company, EV Energy Partners, L.P. and EV Energy GP, L.P. within the
      meaning of the Act and the applicable rules and regulations thereunder
      adopted by the Securities and Exchange Commission ("SEC") and the Public
      Company Accounting Oversight Board (United States) ("PCAOB").

2.    In our opinion, the combined financial statements of the Company, the
      balance sheet of EV Energy Partners, L.P. and the balance sheet of EV
      Energy GP, L.P. audited by us and included in the registration statement
      comply as to form in all material respects with the applicable accounting
      requirements of the Act and the related rules and regulations adopted by
      the SEC.

3.    We have not audited any financial statements of the Company as of any date
      or for any period subsequent to December 31, 2005; although we have
      conducted an audit for the year ended December 31, 2005, the purpose (and
      therefore the scope) of the audit was to enable us to express our opinion
      on the combined financial statements as of December 31, 2005, and for the
      year then ended, but not on the financial statements for any interim
      period within that year. Therefore, we are unable to and do not express
      any opinion on the unaudited condensed combined balance sheet as of

                               Exhibit C - Page 1



      June 30, 2006, and the unaudited condensed combined statements of
      operations and comprehensive income, cash flows, and changes in owners'
      equity for the six-month periods ended June 30, 2006 and 2005, included in
      the registration statement, or on the financial position, results of
      operations, or cash flows as of any date or for any period subsequent to
      December 31, 2005.

4.    For purposes of this letter, the Company management has represented to us
      that there is no minutes of any meetings of owners of the Combined
      Predecessor Entities. We have carried out other procedures to September
      __, 2006, as follows (our work did not extend to the period from
      September__, 2006 to September ___, 2006, inclusive):

      A.    With respect to the six-month periods ended June 30, 2006 and 2005 -

            (i)   Performed the procedures specified by the PCAOB for a review
                  of interim financial information as described in SAS No. 100,
                  Interim Financial Information, on the unaudited condensed
                  combined balance sheet as of June 30, 2006, and the unaudited
                  condensed combined statements of operations and comprehensive
                  income, cash flows, and changes in owners' equity for the
                  six-month periods ended June 30, 2006 and 2005, included in
                  the registration statement.

            (ii)  Inquired of certain officials of the Company who have
                  responsibility for financial and accounting matters whether
                  the unaudited condensed combined financial statements referred
                  to in 4A(i) comply as to form in all material respects with
                  the applicable accounting requirements of the Act and the
                  related rules and regulations adopted by the SEC.

      B.    Company officials have advised us that no combined financial
            statements as of any date or for any period subsequent to June 30,
            2006, are available.

The foregoing procedures do not constitute an audit conducted in accordance with
the standards of the PCAOB. Also, they would not necessarily reveal matters of
significance with respect to the comments in the following paragraph.
Accordingly, we make no representations regarding the sufficiency of the
foregoing procedures for your purposes.

5.    Nothing came to our attention as a result of the foregoing procedures,
      however, that caused us to believe that --

            (i)   Any material modifications should be made to the unaudited
                  condensed combined financial statements described in 4A(i),
                  included in the registration statement, for them to be in
                  conformity with accounting principles generally accepted in
                  the United States of America.

            (ii)  The unaudited condensed combined financial statements
                  described in 4a(i) do not comply as to form in all material
                  respects with the applicable accounting requirements of the
                  Act and the related rules and regulations adopted by the SEC.

6.    As mentioned in 4B, Company officials have advised us that no combined
      financial statements as of any date or for any period subsequent to [June
      30, 2006], are available; accordingly, the procedures carried out by us
      with respect to changes in financial statement items after [June 30,
      2006], have, of necessity, been very limited. We have inquired of certain
      officials of the Company who have responsibility for financial and
      accounting matters whether (a) at September __, 2006, there was any
      increase in long-term debt or any decreases in combined net current assets
      or owners' equity of the Company as compared with amounts shown on the
      June 30, 2006 unaudited condensed combined

                               Exhibit C - Page 2



      balance sheet included in the registration statement or (b) for the period
      from July 1, 2006, to September __, 2006, there were any decreases, as
      compared with the corresponding period in the preceding year, in combined
      net revenues or net income. On the basis of these inquiries, officials of
      the Company have advised us that there was no increase in long-term debt
      and complete information is not available as to combined net current
      assets or owners' equity as of September __, 2006. Officials of the
      Company have also advised us that complete information is not available
      for combined net revenues or net income for the period July 1, 2006 to
      September __, 2006, as compared to the corresponding period in the prior
      year.

      Officials of EV Energy Partners, L.P. and EV Energy GP, L.P. have advised
      us that no financial statements as of any date or for any period
      subsequent to May 12, 2006, are available; accordingly, the procedures
      carried out by us with respect to changes in financial statement items
      after May 12, 2006, have, of necessity, been limited. We have inquired of
      certain officials of EV Energy Partners, L.P. and EV Energy GP, L.P. who
      have responsibility for financial and accounting matters whether at
      September __, 2006, there was any change in limited partner interests,
      increase in long-term debt, or any decreases in consolidated net current
      assets or Partners' Capital of EV Energy Partners, L.P. and EV Energy GP,
      L.P. as compared to amounts derived from the May 12, 2006 audited balance
      sheets for each such entity included in the registration statement. On the
      basis of these inquires, nothing came to our attention that caused us to
      believe that there was any such change, increase, or decrease, except in
      all instances for changes, increases or decreases that the registration
      statement discloses have occurred or may occur except that _____________.

7.    It should be understood that (1) we make no representations regarding the
      Company's determination and presentation of the non-GAAP measures of
      financial performance or liquidity, Adjusted EBITDA, (2) the non-GAAP
      measures presented may not be comparable to similarly titled measures
      reported by other companies, and (3) we make no comment as to whether the
      non-GAAP measures comply with the requirements of Item 10 of Regulation
      S-K.

8.    At your request, we have --

      A.    Read the unaudited pro forma combined balance sheet as of June 30,
            2006, and the unaudited pro forma combined statements of operations
            for the year ended December 31, 2005, and the six-month period ended
            June 30, 2006, included in the registration statement.

      B.    Inquired of certain officials of the Company who have responsibility
            for financial and accounting matters about --

            (i)   The basis for their determination of the pro forma
                  adjustments, and

            (ii)  Whether the unaudited pro forma condensed combined financial
                  statements referred to in 8A comply as to form in all material
                  respects with the applicable accounting requirements of Rule
                  11-02 of Regulation S-X.

      C.    Proved the arithmetic accuracy of the application of the pro forma
            adjustments to the historical amounts in the unaudited pro forma
            condensed combined financial statements.

The foregoing procedures are substantially less in scope than an examination,
the objective of which is the expression of an opinion on management's
assumptions, the pro forma adjustments, and the application of those adjustments
to historical financial information. Accordingly, we do not express such an
opinion. The foregoing procedures would not necessarily reveal matters of
significance with respect to

                               Exhibit C - Page 3



the comments in the following paragraph. Accordingly, we make no representation
about the sufficiency of such procedures for your purposes.

9.    Nothing came to our attention as a result of the procedures specified in
      paragraph 8, however, that caused us to believe that the unaudited pro
      forma condensed combined financial statements referred to in 8A included
      in the registration statement do not comply as to form in all material
      respects with the applicable accounting requirements of Rule 11-02 of
      Regulation S-X and that the pro forma adjustments have not been properly
      applied to the historical amounts in the compilation of those statements.
      Had we performed additional procedures or had we made an examination of
      the pro forma condensed combined financial statements, other matters might
      have come to our attention that would have been reported to you.

10.   At your request, for purposes of this letter, we have also read the items
      identified by you on the attached copies of pages from the registration
      statement, and have performed the following procedures, which were applied
      as indicated with respect to the cross reference code explained below:

      A     Compared amount(s) to or recalculated amount(s) based on the
            corresponding amount(s) in the Company's 2003, 2004, or 2005 audited
            combined financial statements and footnotes included in the
            registration statement and found such amount(s) to be in agreement.

      B     Compared amount(s) to or recalculated the amount(s) based on the
            corresponding amount(s) in the Company's unaudited combined
            financial statements and footnotes for the six-month periods ended
            June 30, 2005 or June 30, 2006 included in the registration
            statement and found such amount(s) to be in agreement.

      C     Compared to, or derived or recalculated the amount(s) from the
            unaudited pro forma condensed combined statements of operations
            included in the registration statement, and found such amount(s) to
            be in agreement.

      D     Recalculated the arithmetic accuracy of the amount or percentage.

      E     Compared or recalculated amount(s) and/or other information to the
            corresponding amount(s) in analyses prepared by employees of
            EnerVest Management Partners, Ltd. ("EnerVest"), the general
            partner, who have responsibility for accounting for the Company. The
            analyses prepared by EnerVest employees were agreed to or can be
            derived from the accounting records that are subject to the internal
            controls of the Company's accounting system.

      F     Compared amount of capital expenditures of $10.7 million related to
            the acquisition of oil and gas interests in the Monroe field in
            March 2005 to the corresponding amount in the Company's unaudited
            combined financial statements and footnotes for the six-month
            periods ended June 30, 2005 or June 30, 2006 and found such amount
            to be in agreement and we make no comment regarding the
            appropriateness of the amount as a component of the pro forma
            financial statements or pro forma footnotes.

      G     Compared the amount to an analysis prepared by EnerVest employees
            and noted that capital expenditures for the year ended December 31,
            2003 should be $10,736 (in thousands). The amount in the
            registration statement is $10,436 (in thousands).

      H     Compared the amount to an analysis prepared by EnerVest employees
            and noted that the amount spent for the three years ended December
            31, 2005 for drilling in the Northern Louisiana properties should be
            $262,000. The amount in the registration statement is $300,000.

                               Exhibit C - Page 4



      I     Proved the arithmetic accuracy of amounts to be outstanding after
            the issuance of the common units to be offered by means of the
            registration statement and the proposed use of proceeds therefrom,
            as stated under the caption "Use of Proceeds"; however, we make no
            comment regarding the reasonableness of "Use of Proceeds" or whether
            such use will actually take place.

      J     Compared and agreed components of the non-GAAP measure of Adjusted
            EBITDA to line items in an analysis prepared by the Company. The
            amounts contained in such analysis have been prepared using amounts
            included in the audited and unaudited financial statements included
            within the registration statement or can be derived from the
            accounting records that are subject to the internal controls of the
            Company's accounting system. Proved arithmetic accuracy of the
            non-GAAP measure Adjusted EBITDA. (See Paragraph 7 above.)

11.   Our audits of the financial statements for the periods referred to in the
      introductory paragraph of this letter comprised audit tests and procedures
      deemed necessary for the purpose of expressing an opinion on the financial
      statements taken as a whole. For none of the periods referred to therein,
      or any other period, did we perform audit tests for the purpose of
      expressing an opinion on individual balances of accounts or summaries of
      selected transactions such as those enumerated above, and accordingly, we
      express no opinion thereon.

12.   It should be understood that we make no representations regarding
      questions of legal interpretation or regarding the sufficiency for your
      purposes of the procedures enumerated in paragraph 10; also, such
      procedures would not necessarily reveal any material misstatement of the
      amounts or percentages listed above. Further we have addressed ourselves
      solely to the foregoing data as set forth in the registration statement
      and make no representations regarding the adequacy of disclosure or
      regarding whether any material facts have been omitted.

13.   This letter is solely for the information of the addressees and to assist
      the underwriters in conducting and documenting their investigation of the
      affairs of the Company, EV Energy Partners, L.P. and EV Energy GP, L.P. in
      connection with the offering of securities covered by the registration
      statement, and it is not to be used, circulated, quoted, or otherwise
      referred to within or without the underwriting group for any purpose,
      including but not limited to the registration, purchase, or sale of
      securities, nor is it to be filed with or referred to in whole or in part
      in the registration statement or any other document, except that reference
      may be made to it in the underwriting agreement or any list of closing
      documents pertaining to the offering of securities covered by the
      registration statement.

Yours truly,

                               Exhibit C - Page 5



                                   EXHIBIT D

                        ENGINEERS' RESERVE REPORT LETTER

      [This letter, which is written at the request of EV Energy Partners, L.P.
(the "Company"), is being delivered to the Underwriters pursuant to the terms of
an underwriting agreement between [_______] and the Underwriters relating to the
public offering of 3,900,000 common units representing limited partner interests
of the Partnership (the "Common Units"), which are being offered by the
Partnership pursuant to the prospectus dated [______], 2006 (the "Prospectus").

      Our report letter dated [__________] to the Partnership presented our
estimates of Proved Reserves and Future Net Revenues (including discounted
values thereof) attributable to interests of the Partnership as of December 31,
2005 (the "2005 Report"). [In addition, we also delivered previous reports to
the Partnership for the year ended December 31, 2003 and 2004 (the "Previous
Reports").] The 2005 Report and the previous reports are collectively referred
to in this letter as the "Reports".

      In connection with the foregoing, we hereby inform you as follows:

      1.    As of the date of this letter and as of the date of the Reports, we
            are and were independent reserve engineers with respect to the
            Partnership as provided in the standards pertaining to the
            estimating and auditing of oil and gas reserve information
            promulgated by the Securities and Exchange Commission (the "SEC").
            Neither we, nor to our knowledge, any of our employees, officers or
            directors, own interests in the oil and gas properties included in
            the Reports. We have not been employed by the Partnership on a
            contingent basis.

      2.    All terms used in this letter, where applicable, conform to the
            definitions set forth in Rule 4-10 of Regulation S-X promulgated by
            the SEC.

      3.    The estimates of the Partnership's Proved Reserves, Future Net
            Revenues and the discounted values of Future Net Revenues contained
            in the Reports, and the computations made in connection therewith,
            were, unless otherwise stated, made in accordance with the
            provisions of Rule 4-10 of Regulation S-X promulgated by the SEC and
            have been prepared in a manner consistent and in compliance with the
            standards and definitions pertaining to the estimating and auditing
            of oil and gas reserve information promulgated by the SEC.

      4.    The engineering projections included in the [2005 Report] were based
            on the latest available production data, the majority through
            [December] 2005. [Although we were not requested to review
            subsequent data concerning either the performance of the wells or
            field operations, no additional information has been brought to our
            attention that would lead us to believe that there would be a
            material change in the estimated Proved Reserves or Future Net
            Revenues attributable to the Partnership's interests reflected in
            the 2005 Report.]

                               Exhibit D - Page 1



      5.    You may rely upon our Reports in the same manner as if such report
            were addressed to you.

      6.    We have reviewed the circled reserve information on pages attached
            hereto as Appendix A from the Prospectus dated ________, 2006. We
            confirm that such circled information labeled "A" in the right
            margin has been accurately derived from our Reports. [Our Reports do
            not present proved reserve information presented on a barrel or Mcf
            equivalent basis. We have, however, confirmed that to the extent
            such equivalent unit information is circled in Appendix A, it has
            been accurately calculated using proved reserve volumes from our
            Reports and applying a 6 to 1 ratio to convert Mcf natural gas
            volumes to barrel of oil equivalents or vice versa.] [Discuss with
            Cawley] Circled information labeled "B" in the right margin contains
            information calculated by the company using information from our
            2005 Report aggregated with outside information; we verified these
            values with additional information supplied by the Partnership.
            Circled information labeled "C" in the right margin is not included
            in our Reports and was prepared by the Partnership; we reviewed this
            information with the Partnership and the values appear reasonable
            based on our review; however, we have not independently verified
            this information.

      We hereby consent to the references to our firm and the use of the Reports
as set forth in the Prospectus.

      This letter is solely for the information of the addressees and to assist
the addressees in documenting their investigations in connection with the
offering of the Common Units covered by the Prospectus.

                               Exhibit D - Page 2