Document:

PARTICIPATION AGREEMENT
                           EUGENE ISLAND 357 PROSPECT
                               OFFSHORE, LOUISIANA

         This Participation Agreement ("Agreement") is made and entered into
effective as of the 1st day of July, 2005 by and between Walter Oil & Gas
Corporation ("Walter"), and Ridgewood Energy Corporation ("Ridgewood").

                                    RECITALS

         WHEREAS, Walter has identified a prospect on Eugene Island block 357
and has acquired Oil & Gas Lease OCS-G 23884 dated June 1, 2002 covering block
357 from the United States of America; and, WHEREAS, Walter plans to drill or
participate in the drilling of an initial test well on Eugene Island block 357,
OCS-G 23884; and,

         WHEREAS, Walter has offered to Ridgewood the opportunity to participate
in the drilling of the initial test well and to acquire a 25% working interest
in block 357, OCS-G23884, less and except the NE/4 of the lease from the surface
to 11,500' subsea (hereafter "Lease"), and Ridgewood has accepted Walter's offer
all in accordance with the terms set forth herein.

         NOW, THEREFORE, in consideration of the mutual covenants and agreement
herein contained, the parties hereto agree as follows:

                                    SECTION I
                                  Initial Costs

         1.01     Within ten (10) days of Ridgewood's execution of this
                  Agreement, Ridgewood agrees to pay Walter $141,203.00 (which
                  represents Ridgewood's 25% share of the Lease bonus, rental
                  and shallow hazard survey costs incurred by Walter).

                                   SECTION 11
                                Initial Test Well

         2.01     Walter plans to participate in the drilling of an initial test
                  well on the Lease. The initial test well will be drilled from
                  a surface location of approximately 5,625' FSL and 6,610' FEL
                  of the Lease and drilled to a depth of 15,800' TVD
                  (hereinafter "Initial Test Well"). As consideration for the
                  opportunity to earn a twenty-five percent (25%) working
                  interest in the Lease, Ridgewood shall bear Thirty-Three and
                  One-Third percent (33.33%) of the costs to drill the Initial
                  Test Well to casing point and through plugging and
                  abandonment, if the Initial Test Well is not saved for
                  production. This disproportionate cost sharing obligation
                  shall be referred to as the "Promote." The Promote will be
                  applicable to the dry hole costs of the Initial Test Well and
                  will be limited to 110% of the Initial Test Well's estimated
                  dry hole cost as noted in the attached AFE. The Promote will
                  also apply to any substitute well or sidetrack of the Initial
                  Test Well until Walter has received 110% of the original AFE
                  dry hole costs. Concurrent with Ridgewood's execution of this
                  Agreement, Ridgewood will be deemed to have approved the
                  attached AFE and well plan.

<PAGE>

         2.02     Subject only to rig availability and the ability to obtain the
                  required governmental permits, Walter and Ridgewood agree that
                  if the Initial Test Well is not spudded on or before December
                  1, 2005 ("Commencement Date"), and such date has not been
                  extended by Ridgewood, then this Agreement shall ipso facto
                  terminate. Within 10 days of such termination, Walter shall
                  reimburse Ridgewood for any payments it received in accordance
                  with Paragraph 1.01 of this Agreement and Ridgewood shall
                  submit assignments to Walter re-conveying Ridgewood's 25%
                  working interest in the Lease previously received from Walter,
                  which assignment shall be free and clear of any liens,
                  charges, or lease burdens, overriding royalty interest, or any
                  other encumbrance created by Ridgewood. For clarification
                  purposes only, there shall be no other penalty(ies) assessable
                  to either party hereto for failure of the Initial Test Well to
                  be spudded on or before the Commencement Date.

         2.03     It is understood and agreed that Newfield Exploration Company
                  (`Newfield") will have a 50% working interest in the Lease and
                  Initial Test Well and will be the designated operator.

                                   SECTION III
                       Assignment and Assumption of Rights

         3.01     Within ten (10) days from receipt of Ridgewood's payment
                  described in 1.01 above, Walter shall assign to Ridgewood
                  Twenty Five percent (25%) operating rights interest in the
                  Lease. The interest assigned to Ridgewood in the Lease shall
                  be subject to the existing royalty burden and a 2.25% of
                  8/8ths overriding royalty interest ("ORRI") to be reserved by
                  Walter, all proportionately reduced to Ridgewood's assigned
                  interest. Walter represents to Ridgewood that total Lease
                  burdens created by, through and under Walter as of the
                  effective date of this Agreement, including lessor's royalty,
                  are no greater than 18.917% (of 8/8ths). The form of
                  Assignment is attached hereto as Exhibit "A."

                                   SECTION IV
                               Operating Agreement

         4.01     Contemporaneous with the execution of this Agreement, the
                  parties hereto agree to execute a mutually agreeable operating
                  agreement ("JOA"), naming Newfield operator of the Lease. Both
                  parties hereto acknowledge that the JOA is a three-party
                  agreement also requiring Newfield's signature. All operations
                  on the Initial Test Well and any and all subsequent operations
                  on the Lease shall be conducted in accordance with the terms
                  and provisions of the JOA. If there are any conflicts between
                  this Agreement and the JOA, the terms and provisions of this
                  Agreement shall prevail and govern.

                                    SECTION V
                                     Notices

         5.01     All notices, requests or demands to be given under this
                  Agreement shall be in writing and governed and directed to the
                  representatives as specified below:

           Ridgewood Energy Corporation        Walter Oil & Gas Corporation
           11700 Old Katy Rd., Suite 280       1100 Louisiana Street, Suite 200
           Houston, Texas    77079             Houston, TX      77002
           Attn: Mr. W. Greg Tabor             Attn: Mr. Ron Wilson

<PAGE>

           Phone: 281-293-8449                 Phone: 713-659-1221
           Fax:   281-293-7705                 Fax:   713-756-1177

                                   SECTION VI
                      GOVERNING LAW AND BREACH OF CONTRACT

         6.01     This Agreement shall be governed by the laws of the State of
                  Texas except where the Maritime Laws of the United States of
                  America are applicable. In the event that any dispute results
                  in formal legal action, venue shall be appropriate in the
                  federal or state courts of Harris County, Texas.

         6.02     In the event of a breach of this Agreement by any party
                  hereto, the non-breaching party shall be entitled to all
                  remedies available at law or equity, including but not limited
                  to, specific performance, monetary damages and injunctive
                  relief.

                                   SECTION VII
                                  MISCELLANEOUS

         7.01     Walter shall provide Ridgewood with full and complete access
                  to Walter's files, records and data, so that Ridgewood may
                  perform its due diligence review of Walter's acquisition,
                  ownership and obligations associated with the Lease.
                  Additionally, Walter shall provide Ridgewood with access to
                  its technical data associated with the Lease, including
                  seismic, maps, well data and geological data, subject however,
                  to all confidentiality and data licensing restrictions.

         7.02     A term, provision, covenant, representation, warranty, or
                  condition of this Agreement may be waived only by written
                  instrument executed by the party waiving compliance. The
                  failure or delay of any party in the enforcement or exercise
                  of the rights granted under this Agreement shall not
                  constitute a waiver of said rights nor shall it be considered
                  as a basis for estoppel.

         7.03     This Agreement, together with all of its exhibits, is intended
                  by the parties to be a complete and final statement of the
                  agreement of the parties with respect to the subject matter
                  hereof, and supersedes any prior oral or written statements or
                  agreements between the parties hereto.

         7.04     The terms and provisions hereof shall be binding upon and
                  inure to the benefit of Walter and Ridgewood, and their
                  respective heirs, legal representatives, successors and
                  assigns, and shall be covenants running with the Lease.

<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be executed as of the date first set forth above.

WITNESSES                                      WALTER OIL GAS CORPORATION

[ILLEGIBLE SIGNATURE]                          /s/ Ron A. Wilson
                                               --------------------------
                                               Ron A. Wilson
                                               Vice President
[ILLEGIBLE SIGNATURE]

                                               RIDGEWOOD ENERGY CORPORATION

[ILLEGIBLE SIGNATURE]                          /s/ W. Greg Taber
                                               ------------------
                                               Executive 'vice President
[ILLEGIBLE SIGNATURE]

<PAGE>

                                   EXHIBIT "A"

       Attached to and made a part of that certain Participation Agreement
      dated July 1, 2005 between Walter Oil & Gas Corporation and Ridgewood
                               Energy Corporation.

              ASSIGNMENT OF OPERATING RIGHTS TO OIL AND GAS LEASE

                                                                     OCS-G 23884

UNITED STATES OF AMERICA ss.

OUTER CONTINENTAL SHELF ss.

OFFSHORE LOUISIANA ss.

         For and in consideration of the sum of One Hundred Dollars ($100.00)
and other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, Walter Oil & Gas Corporation, a Texas Corporation,
whose mailing address is 1100 Louisiana, Suite 200, Houston, Texas 77002
(hereinafter called "Assignor"), does SELL, TRANSFER, ASSIGN, SET OVER AND
CONVEY unto Ridgewood Energy Corporation, a __________________ Company, whose
mailing address is 11700 Old Katy Rd., Suite 280, Houston, TX 77079,
(hereinafter called "Assignee"), a 25.0000% operating rights interest in and to
the following federal oil and gas Lease ("Lease"):

         Oil and Gas Lease No. OCS-G 23884 dated June 1, 2002 from the United
         States of America, as Lessor, to Walter Oil & Gas Corporation, as
         Lessee, covering Eugene Island Area, Block 357, OCS Leasing Map,
         Louisiana Map No. 4A, containing 4999.88 acres;

         LESS AND EXCEPT the Northeast Quarter (NE14) of the Lease from the
         surface down to 11,500' subsea (hereinafter referred to as ("Assigned
         Interest").

Subject to the matters set forth herein, this Assignment is made without
warranty of title, express, implied or statutory, even for return of any
consideration paid therefor; provided only that Assignor warrants that it has
not heretofore granted or conveyed to any other party any interest in or any
lien or encumbrance on the interest being assigned hereunder in the Lease except
as described herein.

<PAGE>

WITH RESPECT TO ANY PERSONALTY OR CHATTELS CONVEYED HEREBY, ASSIGNOR HEREBY
NEGATES AND DISCLAIMS THE IMPLIED WARRANTY OF MERCHANTABILITY AND THE IMPLIED
WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE AND ANY IMPLIED WARRANTY OF
CONFORMITY TO MODELS OR SAMPLES OF MODELS. ASSIGNEE AND ASSIGNOR AGREE THAT, TO
THE EXTENT REQUIRED BY APPLICABLE LAW TO BE EFFECTIVE, THE DISCLAIMERS OF
CERTAIN WARRANTIES CONTAINED IN THIS INSTRUMENT ARE "CONSPICUOUS" DISCLAIMERS.

         TO HAVE AND TO HOLD the Assigned Interests hereby conveyed, together
with all and singular rights and appurtenances thereto in anyway belonging unto
Assignee, its successors and assigns.

         This Assignment is made by Assignor and accepted by Assignee subject to
the following:

1)       the terms, provisions and conditions of the Lease and any limitation on
         or contained in the Lease; 2) That certain Participation Agreement
         dated July 1, 2005 by and between Assignor and Assignee and covering
         the Assigned Interest;

3)       That certain Offshore Operating Agreement dated July 1, 2005 by and
         between Newfield Exploration Company, as Operator, and Assignor and
         Assignee, as Non-Operators, and covering the Assigned Interest;

4)       Assignor reserves unto itself, and retains an overriding royalty
         interest equal to 2.25% of eight-eights (8/8ths) in and to all
         hydrocarbons that are produced, saved, and sold from the Lease. Said
         overriding royalty shall be free of all costs of any kind whatsoever
         including but not limited to costs associated with exploration,
         development, production or operating, but shall bear its proportionate
         share of severance and production taxes unless provided otherwise in
         the Lease. Said overriding royalty shall be calculated and paid or
         delivered to Assignee in the same manner as provided in the Lease
         affected thereby for the calculation and payment or delivery of
         royalties therein reserved to the Lessor,

         a) It is understood that the overriding royalty interest reserved
         hereinabove is an 8/8ths number and that Assignee shall bear its
         proportionate share of such overriding royalty interest based on the
         Assigned Interest herein.

4)       The terms and conditions of this Assignment shall extend to and be
         binding upon the successors and assigns of the parties.

<PAGE>

         IN WITNESS WHEREOF, this Assignment of Operating Rights Interest is
executed and effective this day of, 2005.

WITNESSES:                                              ASSIGNOR:

                                               Walter Oil & Gas Corporation
________________________
________________________
                                               By: ________________________
                                                     Ron A. Wilson
                                                     Vice President

WITNESSES:                                              ASSIGNEE:

                                               Ridgewood Energy Corporation
________________________
________________________
                                               By: ________________________
                                                     W. Greg Tabor
                                                     Executive Vice President

STATE OF TEXAS

COUNTY OF HARRIS

         On this _____ day of __________ 2005 before me appeared W. Greg Tabor,
to me personally known, who, being by me duly sworn, did say that he is the
Executive Vice President of Ridgewood Energy Corporation, and that the foregoing
instrument was signed on behalf of said company, and said W. Greg Tabor
acknowledged said instrument to be the free act and deed of said corporation.

                                               __________________________
                                                     NOTARY PUBLIC

My Commission Expires __________________________.

<PAGE>

STATE OF TEXAS

COUNTY OF HARRIS

         On this _____ day of __________ 2005 before me appeared before me
appeared Ron A. Wilson, to me personally known, who, being by me duly sworn, did
say that he is the Vice President of Walter Oil & Gas Corporation, and that the
foregoing instrument was signed on behalf of said partnership, and said Ron A.
Wilson acknowledged said instrument to be the free act and deed of said
corporation.

                                               __________________________
                                                     NOTARY PUBLIC

My Commission Expires __________________________.

<PAGE>

[NEWFIELD LOGO]
                               Authorization for Expenditure

[ILLEGIBLE TABLE]

<PAGE>

                                                Newfield
                                                Exploration
                                                Company
                                                Authority
                                                For
                                                Expenditure

<PAGE>

                  Newfield Exploration Company, Authority For
                                   Expenditure
<TABLE>
<CAPTION>
Well Name: El 357                                     WELL: #1                                                    18-Jul-05

AFE Type: Exploration

AFE NUMBER:                8955                                                    PRE
AFE Description:     DRILL & EVALUATE                                    DHC      COMPLETE      COMPLETE         TOTAL

    1 850            DRILLING INTANGIBLE GROSS
<C>   <C>            <C>                                                   <C>                                    <C>
850  .001            LOC PERMITS                                           5,000                                  5,000
850  .002            LOC SURVEYS                                          25,000                                 25,000
850  .003            LOC PREPARATION                                           0                                      0
850  .004            LOC CLEAN UP                                              0                                      0
850  .005            LOC INSURANCE                                       132,000                                132,000
850  .006            LOC MISC                                                  0                                      0
850  .007            LOC CONTINGENCY                                   1,368,100                              1,368,100
850  0.011           DRLO MOB DEMOB                                      650,000                                650,000
850  .012            DRLG RIG                                          5,520,000                              5,520,000
850  .013            DRLG FUEL                                           241,500                                241,600
850  .014            DRLO WATER                                            9,200                                  9,200
850  .015            DRLG BITS                                           123,000                                123,000
850  .016            DRLt3 TOOLS - STAB,H.UR                              19,800                                 19,800
850  .021            MUD CHEMICALS                                       835,300                                835,300
850  .022            MUD COMPLETION FLUIDS                                     0                                      0
850  .023            MUD CORROSION INHIBITOR                                   0                                      0
850  .024            MUD ACID                                                  0                                      0
850  .026            RENT BOPS                                             8,600                                  8,600
850  .027            RENT DRIB. STRING                                    92,300                                 92,300
850  .029            RENT MUD EQUIPMENT                                  24,200                                 24,200
850  .029            RENT CASING TOOLS                                   100.000                                100,000
850  .030            RENT COMMUNICATIONS                                  32,400                                 32,400
850  .031            RENT ELECT LINE UNIT                                      0                                      0
850  .032            RENT TESTING UNIT                                         0                                      0
850  .033            RENT MISC                                             4,000                                  4,000
850  .036            CEMENT                                              305,000                                305,000
850  .041            SERVICES MUD LOGGING                                 50,600                                 59,600
850  .042            SERVICES OPEN HOLE LOOOINO                          390,000                                390.000
850  .043            SERVICES CASINO HOLE LOGGING                              0                                      0
850  .044            SERVICES DIRECTIONAL SURVEY                           5,000                                  5,000
850  .045            SERVICES CASINO INSPECTION                           20,800                                 20,800
850  .046            SERVICES TUBING INSPECTION                                0                                      0
850  .047            SERVICES TUBING TESTING                                   0                                      0
850  .048            SERVICES DRILL. PIPE INSPEC                               0                                      0
850  .049            SERVICES BHA INSPEC                                   5,300                                  5,300
850  .050            SERVICES GALLEY                                      27,800                                 27,600
850  .051            SERVICES TRASH                                        5,600                                  8.600
850  .052            SERVICES WELDING & LABOR                              8,000                                  8,000
850  .053            SERVICES CORE ANALYSIS                                    0                                      0
850  .054            SERVICES FISHING TOOLS                                    0                                      0
850  .055            SERVICES DIRECTIONAL TOOLS                                0                                      0
850  .056            SERVICES 80P TESTING                                      0                                      0
850  .057            SERVICES MUDLINE HANGER                               6,000                                  6,000
850  .058            SERVICES WELLHEAD                                     6,000                                  6,000
850  .059            SERVICES CEMENTING                                   95,100                                 85,100
850  .060            SERVICES DOCKS                                       32,200                                 32,200
850  .061            SERVICES DISPATCHER                                  32,200                                 32,200

                                                                                                               7/18/2005
</TABLE>

<PAGE>

                   Newfield Exploration Company, Authority For
                                   Expenditure
<TABLE>
<CAPTION>
Well Name: El 357                                     WELL: #1                                                18-Jul-05

AFE Type: Exploration

AFE NUMBER:                8955                                                    PRE
AFE Description:     DRILL & EVALUATE                                    DHC      COMPLETE      COMPLETE          TOTAL
<C>   <C>            <C>                                                   <C>                                    <C>
850  .062            SERVICES DIVERS                                           0                                     (0)
850  .063            SERVICES LLNER HANGER                                     0                                      0
850  .064            SERVICES GRAVEL PACK                                      0                                     (0)
850  .065            SERVICES ACIDIZ1NG                                        0                                     (0)
850  .066            SERVICES MISC                                        48,000                                 48,000
850  .071            TRANS TRUCKING                                       69,000                                 69,000
850  .072            TRANS WORKBOATS                                     299,000                                299,000
850  .073            TRANS TUGS                                                0                                      0
850  .014            TRANS CREWBOATS                                     138,000                                138,000
850  .075            TRANS AIR                                           165,800                                185,600
850  .076            TRANS FUEL                                          120,800                                120,800
850  .077            TRANS MISC                                                0                                      0
850  .081            SUPR ADMIN                                           46,000                                 46,000
850  .082            SUPR CONSULTANT                                     119,600                                119,600
850  .083            SUPR ENGINEER                                         7,200                                  7,200

           SUBTOTAL                $50                               511,163,000                            $11,193,000

   1 853             DRILLINO TANGIBLE COST

853  .01             PIPE CAISSON                                              0                                      0
833  .02             PIPE DRIVE                                          187,200                                187,200
853  .03             PIPE CONDUCTOR                                      163,500                                183,500
853  .04             PIPE SURFACE                                        435{000                                435,000
853  .05             PIPE INTERMEDIATE                                   584,600                                684,500
853  .06             PIPE PRODUCTION                                           0                                      0
853  .07             PIPE LINER                                                0                                      0
853  .08             PIPE TIEBACK                                              0                                      0
853  .09             PIPE TUBING                                               0                                      0
853  .16             WELLHEAD                                             44,000                                 44,000
853  .25             CASING EQUIPMENT                                    162,500                                162,500
853  .31             CETUBTNG ACC                                              0                                      0
853  .32             CE SSSV                                                   0                                      0

           SUBTOTAL               833                              $   1,576,700                             11,576,700

T0TAL AFE#                   8955                                  $  12,759,700                           $ 12,759,700

                                                                                                              7/18/2005
</TABLE>

APPROVED: [ILLEGIBLE SIGNATURE]                [ILLEGIBLE INITIALS]

DATE: 7/20/05

<PAGE>

                          NEWFIELD EXPLORATION COMPANY

                               GENERAL INFORMATION

      Field                                     Eugene Island Block 357

      Well Name                                 EI 367 #1

      OCS-G                                     23884

      AFE No.                                   8965

      Permit Depth                              16,500' MD 116,500' TVD

      Water Depth /Elevation (RKB to MSL)       1320' / +- l00' est.

      Drilling Contractor/ Rig Name / Type      Rowan/ Gorilla IV I ILC Jack-up

      Operating Port or Facility                Fourchon, Louisiana

      Port Distance From Well                   +-120 miles

  WELL LOCATION
--------------------------------------------------------------------------------
Surface Location           5,610' FSL           6,750' FEL     EI 357
--------------------------------------------------------------------------------
                                  X                    Y
--------------------------------------------------------------------------------
                                  Lat                  Long
--------------------------------------------------------------------------------
Bottom Hole Location       5,610' FSL           6,760' FEL     EI 367
--------------------------------------------------------------------------------

WELL TYPE:            [X] Vertical Well     [_]Directional Well
--------------------------------------------------------------------------------
KOP         NA  Inclination   NA   Azlmuth  NA   Build Rate  NA   Drop Rate  N/A
--------------------------------------------------------------------------------
2nd Build   NA  Inclination   NA   Azlmuth  NA   Build Rate  NA   Drop Rate  NA
--------------------------------------------------------------------------------

GEOLOGICAL OBJECTIVES AND TARGET DESCRIPTION
--------------------------------------------------------------------------------
Bul I Sand   14,480'   TVD 150'Radius    5,610' FSL   6,750'  FEL  EI 367
--------------------------------------------------------------------------------
  2 Obj      15,300'   TVD 150'Radius    6,610  FSL   8 760'  FEL  EI 357
--------------------------------------------------------------------------------

<TABLE>
<CAPTION>
PERMITTED CASING PROGRAM
------------------------------------------------------------------------------------------------------
Casing Point            Casing Size  Casing Wt       Casing Grade  Casing Conn.    RKB MD      RKB TVD
------------------------------------------------------------------------------------------------------
<S>                     <C>          <C>             <C>           <C>             <C>         <C>
Drive Pipe              36" x 1.0"   374 ppf         X-56          DDS             720'        720'
------------------------------------------------------------------------------------------------------
Conductor                 20"        106.5 ppf       J-55          BTC             1,500'      1,500'
------------------------------------------------------------------------------------------------------
Surface                 13-3/8"      68 ppf          HCN-80        BTC             5,000'      5,000'
------------------------------------------------------------------------------------------------------
Drilling  Intermediate  9-5/8"       53.5 ppf        HCP-110       LTC             8,000'      8,000'
------------------------------------------------------------------------------------------------------
Drilling Liner          7-5/8"       39 ppf          HCP-110       STL             12,000'     12,000'
------------------------------------------------------------------------------------------------------
Production Liner          5"         18 ppf          HCP-110       STL             16,500'     16,500'
------------------------------------------------------------------------------------------------------
</TABLE>

<PAGE>

                          NEWFIELD EXPLORATION COMPANY

PROPOSED GEOLOGICAL EVALUATION PROGRAM
-----------------------------------------------------
 Conductor Hole          None
-----------------------------------------------------
 17-1/2" Surface Hole    LWD: None
                         E-Log:  None
-----------------------------------------------------
 12-1/4" Hole            LWD: GR/Res
                         E-LOG: None Planned
                         ----------------------------
                         Mudlogging: 5,000' to Csg Pt
-----------------------------------------------------
 8-1/2" Hole             LWD: GR/Res
                         E-LOG: None Planned
                         ----------------------------
                         Mudlogging: 8,000' to Csg Pt
-----------------------------------------------------
 6-1/2" Hole             LWD: GRI/Res
                         ----------------------------
                         E-LOG: DIL/LDT/CNL/GR
                         Possible SWC's
-----------------------------------------------------
                         Mudlogging: 12,000' to TD
-----------------------------------------------------

<PAGE>
                         NEWFIELD EXPLORATION COMPANY           [NEWFIELD LOGO]
                           EUGENE ISLAND BLOCK 357 #1
                                  WELL SUMMARY

                               [ILLEGIBLE TABLE]

<PAGE>

                             NEWFIELD EXPLORATIONS
                                   EI 357 #1

                            [GRAPHIC CHART OMITTED][GRAPHIC OMITTED]
--------------------------------------------------------------------------------
                                                 Devon Energy Corporation
                                                 Devon Energy Tower
                                                 1200 Smith Street, Suite 3300
                                                 Houston, Texas 77002

Shane VanderCruyssen
Offshore Landman
Direct Line: (713) 286-5832
Fax: (713) 286-5737
Email: mark.gress@dvn.com

September 15, 2005                                           VIA OVERNIGHT MAIL
                                                             ------------------

Ridgewood Energy Corporation
11700 Old Katy Road, Suite 280
Houston, Texas 77079
Attn: Randy Bennett

Re:      Mercury Prospect Participation Agreement
         Eugene Island Area,  South  Addition,  Block
         337; OCS-G 03332 OCS Gulf of Mexico

Gentlemen:

         This Participation Agreement ("Agreement"), when fully executed, sets
forth the terms and conditions under which Devon Energy Production Company, L.P.
("Devon"), as Operator, and Ridgewood Energy Corporation ("Ridgewood"), as
Non-Operator, have agreed to jointly drill an Initial Test Well ("ITW") on
Eugene Island Area, South Addition, Block 337, OCS-G 03332, hereinafter
sometimes referred to as the "Lease". When accepted by Ridgewood, this
Agreement, together with Exhibits "A", "B", "C", "D", "E" and "F attached hereto
shall constitute the entire Agreement by and between Devon and Ridgewood,
to-wit:

    1.   Contract Area
         The "Contract Area" shall be defined as all of Eugene Island Area,
         South Addition, Block 337, OCS-G 3332, to all depths,

         LESS AND EXCEPT the following lands to the areal extent and depths
         hereinafter described:

         A. The Orange Acreage.
            The following described lands as to all depths:

            i).   The Southwest Quarter of the Northeast Quarter (SW4 NE4);
            ii).  The West Half of the Southeast Quarter (W2 SE4); and
            iii). The Southeast Quarter of the Southwest Quarter (SE4 SW4).

<PAGE>

         B.   The Blue Acreage.
              The following described lands contributed to that certain Joint
              Venture Agreement dated May 1, 2002, by and between Devon, et al,
              and Apache Clearwater Operations, Inc., as to depths from the
              surface down to the stratigraphic equivalent of one hundred feet
              (100') below the base of the B-1 (HB-l) Sand as seen in the
              Pennzoil Company OCS-G 3332 Well No. A-5 (API Well Serial No.
              17-710-41022-00) at a depth of 5,920' (TVD):

              i). The South Half of the Southwest Quarter of the Southwest
              Quarter (S2 SW4 SW4); and

              ii).The Southwest Quarter of the Southeast Quarter of the
              Southeast Quarter (SW4 SE4 SE4).

         C. The Green Acreage.
              The following described lands contributed to the JD Sand Reservoir
              A Unit, Eugene Island Block 330 Field, bearing Federal Unit No.
              14-08-001-16943, dated effective April 1, 1977, as to the vertical
              subsurface interval of the JD Sand, Reservoir A, as seen in the
              Eugene Island Block 330 Well No. B-6 (API Well No.
              17-710-40105-00) between the measured depths of 7026 feet and 7222
              feet:

              i). 71.10 acres, more or less, and being all that portion of the
              Lease within the geographic boundaries of the JD Sand
              Reservoir A Unit, Eugene Island Block 330 Field.

              All as more fully illustrated on Exhibit "A" attached hereto and
              made a part hereof.

2.   Initial Test Well / AFE / Contact Spud Date / Contract Depth
     Subject to rig availability, acquiring all the necessary governmental and
     regulatory permits and approvals, and the additional provisions of Article
     23, Force Majeure, below, Devon, as Operator, will commence operations for
     the drilling of the ITW by December 31, 2005, hereinafter the "Contract
     Spud Date". Said ITW will be drilled at a surface location on the existing
     Eugene Island Area, South Addition, Block 337 "A" Platform located
     approximately 1,939 feet from the south line and 6,522 feet from the west
     line of said Block 337 and to a projected bottom hole location
     approximately 617 feet from the west line and 8,661 feet from the south
     line of Eugene Island Area, South Addition, Block 337 as shown on the
     directional plot attached to this Agreement. The ITW will be drilled to a
     depth of 12,860' TVD, or a minimum depth sufficient to test the L-5 Sand or
     its equivalent interval, or to such mutually agreed to deeper depth,
     hereinafter the "Contract Depth". The ITW will be drilled, evaluated and
     completed in accordance with the terms of the Joint Operating Agreement
     (JOA) attached hereto as Exhibit "C", and the Drilling AFE, directional
     plan, casing program, and logging plan attached hereto as Exhibit "B". The
     attached Drilling AFE will be executed by the parties contemporaneously
     with the execution of this Agreement.

3.   The Promote (1/3 for 1/4) and Prospect Fee
     Ridgewood will participate in the drilling of the ITW and the estimated dry
     hole costs associated with drilling same allocated on the basis of 33.33%
     for 25% in order for Ridgewood to earn a 33.00% working interest in the
     Contact Area. Thus, Ridgewood will pay 44.00% of the ITW's estimated dry

<PAGE>

     hole costs as set forth on the attached Drilling AFE as limited pursuant to
     Article 4 below, although Ridgewood will only earn a 33.00% working
     interest in the Contract Area. This disproportionate cost sharing
     obligation shall be hereinafter referred to as the "Promote". Within seven
     (7) days of execution of this Participation Agreement Ridgewood will pay to
     Devon a Prospect Fee of $750,000, proportionately reduced to Ridgewood's
     earned interest.

4.   The Promote Limit (120% of Original DHC .AFE)
     The Promote will be applicable to the original estimated dry hole cost of
     the ITW as set forth in the Drilling AFE and will be limited to 120% of
     such dry hole costs until the ITW reaches Contract Depth. The Promote will
     also apply to any Substitute ITW (as defined below) and/or sidetracking
     operations in the ITW until an amount equal to 120% of the original
     estimated dry hole costs have been fully expended, it being agreed that the
     Promote to be paid by Ridgewood shall be limited to an amount equal to
     44.00% of 8/8ths of 120% of the total estimated dry hole costs of
     $11,957,000 set forth on Drilling AFE and, notwithstanding the foregoing,
     Ridgewood's obligation to pay the Promote to Devon shall cease upon
     reaching Contract Depth in the ITW or Substitute ITW. Upon the earlier of
     the Promote being expended or Contract Depth being reached, all other costs
     incurred in the ITW or Substitute ITW, including but not limited to
     drilling, completion and subsequent development costs, will be shared with
     Devon having a 50% working interest, Ridgewood a 33% working interest and
     Forest a 17% working interest. Devon shall have the right and option to
     cash call Ridgewood for its entire promoted share of the estimated dry hole
     costs of the ITW as set forth in the Drilling AFE not sooner than 30 days
     prior to the commencement of the drilling such ITW.

5.   Initial Test Well/Substitute Initial Test Wells / Shallow Earning Right
     If during the drilling of the ITW, but before reaching Contract Depth in
     such well, mechanical difficulties, heaving shale, rock salt, excessive
     saltwater flow, practically impenetrable formations or other conditions
     including force majeure occurrences as described in Article 23 herein are
     encountered which would cause a reasonable and prudent operator under the
     same or similar circumstances to discontinue drilling operations and plug
     and abandon such well, or if the ITW is drilled to Contract Depth and is
     plugged and abandoned as a dry hole (either well described above to be
     hereinafter referred to as the "Discontinued Well") then for a period of
     one hundred and eighty (180) days from the date of rig release either party
     shall have the right to propose the drilling of another well or
     sidetracking operations on a Discontinued Well (hereinafter referred to as
     the "Substitute ITW") on the Contract Area. In each case the party
     receiving a proposal for a Substitute ITW shall have a period of thirty
     (30) days from the date of its receipt (or forty-eight (48) hours,
     inclusive of Saturdays, Sundays and legal holidays, if the drilling rig is
     on location) to respond to such drilling proposal.

     (a).     If Devon proposes a Substitute ITW within the time above provided
              and the original dry hole cost set forth in the Drilling AFE has
              not theretofore been fully expended, then Ridgewood shall
              participate in the proposed Substitute ITW.

     (b).     If Devon proposes a Substitute ITW within the time above provided
              and the original dry hole cost set forth in the Drilling AFE has
              been fully expended, and Ridgewood elects not to participate or
              fails to respond within the time prescribed above then Ridgewood
              will thereby forfeit its right to ear any interest in the

<PAGE>

              Contract Area and this Agreement shall terminate, subject however
              to the additional provisions of subparagraph (e) below and to
              Article 24, Confidentiality, and Article 26, Confidential Data.

     (c)      If Ridgewood proposes a Substitute ITW within the time above
              provided and Devon elects not to participate or fails to respond
              within the time prescribed above then said Substitute ITW will be
              drilled subject to the non-consent penalties prescribed in the
              JOA, limited to the proposed Substitute ITW only.

     (d).     If such Substitute ITW is proposed within the time above provided
              and drilled and completed to the Contract Depth in compliance with
              all terms and conditions provided herein for the ITW, then the
              Substitute ITW shall in all respects be considered as if it were
              the ITW.

     (e).     Notwithstanding the provisions of subparagraphs 5(a), 5(b),
              5(c) and 5(d) above, and Article 6, Earned Interest, below, if
              neither the ITW, Discontinued Well(s) nor the Substitute
              ITW(s) reach Contract Depth, but based on log analysis, or
              other empirical evidence, a zone, formation or horizon
              encountered in any such well in which Ridgewood participates
              appears to be productive, and such well meets the criteria
              which determines that it is a well capable of producing
              hydrocarbons in commercial quantities pursuant to the
              provisions of 30 CFR 250.115 or 30 CFR 250.116 "Shallow
              Earning Right", then Ridgewood shall earn for its
              participation in such well (hereinafter referred to as an
              "Earning Well") an assignment of 33% of 6/6ths operating
              rights interest under the Contract Area, limited in depth from
              the surface down to the stratigraphic equivalent of the base
              of the deepest productive subsurface interval encountered in
              such well. Provided, however, the Promote (or any unexpended
              portion thereof) to be paid by Ridgewood shall continue to
              apply to any Substitute ITW in which it has elected to
              participate.

6.   Earned Interest - ITW Drilled to Contract Depth and Productive
     If the ITW is drilled to Contract Depth and results in a well capable of
     producing in paying quantities pursuant to the provisions of 30 CFR 250.115
     or 250.116, and Ridgewood has satisfied all its monetary obligations,
     including paying the Promote and Prospect Fee, plus its proportionate share
     of remaining costs and expenses of the ITW, and Ridgewood is in compliance
     with all of the terms and conditions hereof, then Ridgewood will earn for
     its participation in such Earning Well an assignment of 33% of 6/6ths
     operating rights interest to all depths under the Contract Area, subject to
     subparagraph 5(e) above. The interest being assigned to Ridgewood shall be
     subject only to their proportionate share of Lessor's royalty & shall not
     be subject to any overriding royalty, net profits interest or other similar
     burden on production.

7.   Form of Assignment and DOO
     Any assignment of earned interest hereunder shall be delivered to Ridgewood
     in substantially the form attached hereto as Exhibit "E", and at Devon's
     election, may include such of the provisions of this Agreement as Devon
     deems appropriate to include. Simultaneously with the execution of the
     assignment, Ridgewood agrees to execute Designation of Operator forms
     naming Devon Energy Production Company, L.P. as Operator of the Contract
     Area defined in Article 1 above with the Minerals Management Service.

<PAGE>

8.   Subsequently Created Interests
     If any party creates a royalty, overriding royalty, net profits interest,
     production payment or other similar interest (a "Subsequently Created
     Interest") before or after the execution of this Agreement, such
     Subsequently Created Interest shall be subordinate to this Agreement and
     the Exhibits attached hereto. The party creating the Subsequently Created
     Interest shall at all times be responsible for paying or otherwise
     satisfying it. If the party creating the Subsequently Created Interest is
     required to assign or relinquish to any other party all or a portion of its
     working interest and/or the production attributable there to, said other
     party shall receive said assignment and/or production free and clear of
     said Subsequently Created Interest and the burdened party shall defend and
     indemnify the other party from and against any and all claims, causes of
     action, damages, liabilities and judgments arising out of or related to the
     Subsequently Created Interest.

9.   Prior Obligations and Liabilities
     Ridgewood shall not be liable and Devon shall indemnify and defend
     Ridgewood and its officers, directors, agents, servants, and employees
     (collectively "Indemnitees) from and against any penalties, claims, suits,
     costs, expenses, damages, judgments or other liabilities including
     attorney's fees, of any nature whatsoever ("collectively Claims"),
     resulting directly or indirectly from or arising out of or in connection
     with Devon's ownership and operatorship of the Leases which arose or
     hereinafter arise out of any operations or activities on the Contract Area
     where such operations or activities occurred prior to the effective date of
     this Agreement, including, but not limited to, the abandonment of all
     wells, platforms, facilities, and pipelines on the Contract Area and
     existing as of the date of this Agreement.

10.  Title, Approvals, and Consents to Assign
     Devon represents that it currently owns 98% of 6/6ths record title interest
     in the Lease however; Devon makes no representation that the Lease has been
     maintained in full force and effect by payment of any rentals, operations,
     production in paying quantities or by any other method. Further, Ridgewood
     agrees that it has conducted its own due diligence and title search and is
     satisfied as to all matters relating to Devon's title to the interests
     hereunder. Devon and Ridgewood acknowledge and agree that the rights,
     benefits and obligations of the parties under this Agreement shall be
     subject to and contingent upon receiving any governmental approvals
     required by statute or regulation.

11.  Joint Operating Agreement (JOA) - Adjusted COPAS 0/H Rates
     Record title ownership of the Lease (to all depths) as of the date of this
     Agreement is held in the undivided portions 98% Devon and 2% Forest Oil
     Corporation (Forest). The interest of Forest is governed by the terms of
     the JOA attached hereto as Exhibit "C", by and between Pennzoil Offshore
     Gas Operators, Inc., et al, naming Pennzoil Company (now Devon), as
     Operator, and Mesa Petroleum Company, et al (now Forest), as Non-Operator.
     With respect to the non-operating interest of Forest, Devon agrees to
     continue to act as operator under the terms of the JOA as it affects the
     operations to be conducted on the Contract Area under the terms of this
     Agreement.

<PAGE>

     Ridgewood accepts the JOA and ratifies the terms of the JOA for all
     purposes, as if Ridgewood were an original signatory to the JOA.
     Notwithstanding the foregoing, Ridgewood shall never have any liability for
     the cost and liabilities of operations prior to the Effective Date. The JOA
     shall govern the rights, interests and all operations conducted on the
     Contract Area; provided, however, that if there is any conflict between the
     terms of this, Agreement and the JOA, the terms of this Agreement shall
     prevail. Notwithstanding the disproportionate payment provision provided
     herein, Ridgewood shall hold a voting right under the JOA to the extent of
     a 33% working interest share during the drilling operations conducted
     hereunder. Upon Ridgewood earning an interest hereunder, Devon shall
     execute and cause Forest to execute Ratification and Amendment of the JOA
     in substantially the same form as Exhibit "F" attached hereto, adding
     Ridgewood as party to the JOA as to the interest it has earned hereunder.
     If Ridgewood fails to participate in the completion of the Initial Test
     Well and/or Substitute Well, then Ridgewood's rights in and to the JOA
     shall terminate and thereafter such rights shall revert back to Devon.

     Ridgewood agrees that the combined rates to be charged under COPAS Article
     III 1.(B) 2. of the JOA have been adjusted in accordance with COPAS Article
     III 4.(D) thereof such that, as of the date of this Agreement, the drilling
     well rate, is 34,087.27 per well per month and the producing well rate is
     $3,919.36 per well per month, subject to further adjustments on the first
     day of April of each year following the date of this Agreement as permitted
     therein.

12.  Devon Sundry Transactions
     Subject to the post earning provisions of Article 27, Preferential Right to
     Purchase, Devon retains the exclusive right to trade, surrender, or
     otherwise alienate all or any part of its interest in the contract area
     without the necessity of the consent or approval from Ridgewood, provided
     however, Devon agrees that notwithstanding any such trade, surrender, or
     disposition, it shall deliver to Ridgewood its 33% interest in the Contract
     Area, if earned pursuant to Article 5, Substitute ITW /Shallow Earning
     Right, and/or Article 6, Earned Interest, of this Agreement.

13.  Production Handling Agreement (PHA) and Access Fee
     The existing Eugene Island Area, South Addition, Block 337 "A" Platform and
     facilities (EI 337 "A" Facilities) are operated by Devon and owned in the
     proportions 98% Devon and 2% Forest. It is the intent of Devon and
     Ridgewood that said El 337 "A" Facilities will be utilized for the handling
     and processing of all production from the Contract Area. Promptly upon the
     complete execution and delivery of this Agreement, Devon agrees to
     recommend and use its best reasonable efforts to secure a PHA from the
     owners of the El 337 "A" Facilities substantially in the form attached
     hereto as Exhibit "D". In the event the parties fail to agree on a mutually
     agreeable form by the time the operations commence on the ITW, then the
     parties will execute a PHA identical to the one attached as Exhibit "D". On
     complete execution and delivery of the attached PHA, Ridgewood agrees to
     pay its proportional part of the one time slot and access fee within the
     time and manner prescribed in Article II (D.) of the attached PHA.

<PAGE>

14.  Areas of Mutual Interest (AMIs)
     Subject to Article 12, Devon Sundry Transactions, and Article 29, Term as
     of the date of this Agreement the parties establish Areas of Mutual
     Interest (hereinafter collectively referred to as "AMP) with the right of
     participation in the proportions 67% Devon and 33% Ridgewood (hereinafter
     "AMT Interest"), covering the following described lands, as follows;

     (a).     El 337 "The Contract Area"
              For a period commensurate with the term of this Agreement, or for
              a period ending upon Ridgewood's failure to earn any interest in
              the Contract Area under the terms of this Agreement, whichever is
              earlier to occur, but in no event earlier than December 31,2006,
              an AMI, limited to the vertical depth earned by Ridgewood under
              the terms of this Agreement (if any), is established covering the
              Contract Area;

     (b).     EI354
              For a period (i) commensurate with the term of this Agreement, or
              (ii) ending upon Ridgewood's failure to earn any interest in the
              Contract Area, or (iii) ending upon thirty (30) days after the
              date the next ensuing lease is awarded on Eugene Island Area,
              South Addition, Block 354 by the MMS, whichever is earlier to
              occur, but in no event earlier than December 31,2006 an AMI is
              established covering all of Eugene Island Area, South Addition,
              Block 354,

     (b).     El 336
              For a period (i) commensurate with the term of this Agreement, or
              (ii) ending upon Ridgewood 's failure to earn any interest in the
              Contract Area, or (iii) ending upon thirty (30) days after the
              date the next ensuing lease is awarded on Eugene Island Area,
              South Addition, Block 336 by the MMS, whichever is earlier to
              occur, but in no event earlier than December 31, 2006, an AMI is
              established covering Eugene Island Area, South Addition, Block
              336.

     If during the term of the AMI either party ("acquiring party") subsequently
     acquires any oil and gas leases, cash or farmout contributions, or similar
     contracts, or any interests therein, hereinafter collectively "Oil and Gas
     Interest", which affects lands within an AMI, then the other party
     ("non-acquiring party") shall have the right, but not the obligation, to
     acquire from the acquiring party its AMI Interest in such Oil and Gas
     Interest. The non-acquiring party shall be notified by the acquiring party
     of any acquisition, or right to acquire, in writing, to be delivered to
     non-acquiring party (and including the full terms, conditions and
     obligations relating thereto) within thirty (30) days from the date of such
     acquisition, or any right to acquire, and the non-acquiring party shall
     have fifteen (15) days after receipt of such notice to advise the acquiring
     party whether or not the non-acquiring party elects to acquire its AMI
     Interest in the Oil and Gas Interest. If the non-acquiring party elects to
     acquire its AMI Interest in the Oil and Gas Interest, it will also assume
     such pro rata share of all costs and/or obligations attributable to the Oil
     and Gas Interest. Each non-acquiring party who has elected to participate
     in the Oil and Gas Interest shall reimburse the acquiring party for such
     proportional AMI Interest share of the purchase price within thirty (30)
     days from the date of non-acquiring party's election to participate. Upon
     the acquiring party's receipt of said reimbursement, the acquiring party
     shall within thirty (30) days deliver a recordable assignment(s) to the
     non-acquiring parties who have elected to participate in the Oil and Gas
     Interest, which assignments shall be made subject to the additional terms
     and conditions of this Agreement and the JOA, and shall be free and clear

<PAGE>

     of any promotional costs or additional burdens placed thereon by the
     acquiring party but otherwise without warranty of title, express or
     implied, even to the purchase price. A non-acquiring party's failure to
     respond to any such notice within the time and manner above prescribed
     shall be deemed a conclusive election not to acquire any portion of such
     Oil and Gas Interest.

     Notwithstanding anything contained in this Article 14 to the contrary, a
     non-acquiring party's right to acquire shall not apply to any interest
     acquired by an acquiring party as a result of an acquisition related to a
     merger, reorganization or consolidation with a third party, or as a result
     of an acquiring party's acquisition of a larger package of properties from
     a third party which includes other leases situated in the OCS - Gulf of
     Mexico not subject to this Agreement.

15.  Assignability and Binding Effect
     Neither this Agreement nor Ridgewood's rights and obligations hereunder may
     be transferred or assigned, in whole or in part, without Devon's advance
     written consent. Any approved assignment shall made with express assumption
     by such Assignee of all rights and/or obligations contained within this
     Agreement, the JOA, PHA, and any other agreements entered into by the
     parties, provided, Ridgewood, along with all assignee(s), will continue to
     be obligated to Devon for the performance of all obligations incurred under
     this Agreement. The terms and provisions hereof shall be binding upon and
     inure to the benefit of each of the parties hereto and their respective
     legal representatives, successors and assign, and shall be covenants
     running with the land and Lease.

16.  Allocation of Costs Outside the Contract Area
     With respect to any will drilled within the Contract Area that results in a
     dry hole, Devon shall have the right, at their sole election to attempt to
     complete such well outside the Contract Area. All costs for any well
     drilled under the terms of this Agreement that are completed at depths that
     are not a part of the Contract Area shall be allocated among Devon,
     Ridgewood and Forest in accordance with the provisions of Article XVII on
     the same basis as if this JOA covered all of Eugene Island Block 337.

     However; notwithstanding that certain language contained in Article XVII
     (1) that states (For the purpose of this Article XVII "Completion shall
     also mean an objective zone in which no completion is made), for the
     purposes of this agreement and the applicability of Article XVII,
     completion shall not mean an objective zone in which no completion is made.
     Completion shall be defined as an objective zone in which a completion is
     made.

17.  Reassignment on Cessation of Production
     If an assignment has been delivered to Ridgewood pursuant to an Earning
     Well which has been drilled in accordance with the provisions of Article 5,
     Substitute ITW / Shallow Earning Right, and/or Article 6, Earned Interest,
     above, and Ridgewood is in compliance with all of the terms and conditions
     hereof, this Agreement shall remain in effect so long thereafter as there
     is a well on the Contract Area producing oil, gas or other hydrocarbons in
     paying quantities under the terms of this Agreement and/or operations are
     being conducted on the Contract Area under the terms of the JOA and there
     is a lapse of no more than one hundred twenty (120) days between the
     cessation of such production or operations and the restoration of
     production or commencement of operations and/or activity is being conducted
     pursuant to a Suspension of Production (SOP) or Suspension of Operations

<PAGE>

     (SOO). In the event there is not a well producing in paying quantities on
     the Contract Area under the terms of this Agreement and there is a lapse of
     more than one hundred twenty (120) days after cessation of such production
     or operations without production being restored or operations being
     commenced and with no SOP or SOO, then this Agreement shall automatically
     terminate without any further action by either party hereto. In the event
     of termination, Ridgewood shall promptly reassign to Devon, at no cost, all
     of Ridgewood's rights and interests in the Contract Area, which assignment
     shall be free and clear of any overriding royalties, liens, encumbrances,
     or burdens created by through or under Ridgewood.

     Termination of this Agreement shall not operate to relieve Ridgewood from
     the liabilities and/or obligations accrued or incurred under the terms of
     this Agreement prior to such termination, nor relieve Ridgewood of its
     proportional share of the obligation to plug and abandon any wells drilled
     hereunder

18.  Limitation of Warranty
     EXCEPT FOR DEVON'S SPECIAL WARRANTY OF TITLE IN THE ASSIGNMENT REFERENCES
     IN ARTICLE 7 HEREOF, DEVON DISCLAIMS ANY AND ALL OTHER WARRANTIES WITH
     RESPECT TO THE SUBJECT MATTER OF THIS AGREEMENT INCLUDING BUT NOT LIMITED
     TO ANY EXPRESS OR IMPLIED WARRANTY OR REPRESENTATION AS TO MERCHANTABILITY
     OR FITNESS FOR ANY PARTICULAR PURPOSE. ANY INSTRUMENT OF CONVEYANCE OR
     TITLE EXECUTED PURSUANT HERETO SHALL BE EXECUTED WITHOUT ANY OTHER
     WARRANTY, EITHER EXPRESS, IMPLIED, STATUTORY, OR OTHERWISE, AND WITHOUT ANY
     OTHER EXPRESS OR IMPLIED WARRANTY OR REPRESENTATION WHATSOEVER.

19.  Individual Liability
     The rights, duties, elections, obligations, and liabilities of the parties
     shall be several and not joint or collective, and nothing contained herein
     is intended to create, nor shall it be construed as creating, a partnership
     of any kind, joint venture, association, or other business entity
     recognizable at law for any purpose. The parties shall be individually
     responsible only for their own obligations, except as herein described.

20.  Notices
     All notices required hereunder shall be in writing and delivered in person,
     by the U.S. Mail, via courier, express or overnight delivery, or by
     facsimile to the addresses set forth below, and shall be deemed effective
     when actually received by the addressee, as follows:

     Ridgewood Energy Corporation          Devon Energy Production Company, L.P.
     11700 Old Katy Road, Suite 280        1200 Smith Street, Suite 3300
     Houston, Texas 77079                  Houston, Texas 77002
     Attention: Randy Bennett              Attention: Mr. Mark K. Gress
     Phone: (281) 293-9384                 Phone: (713) 286-5858
     Fax: (281) 293-7391                   Fax: (713) 286-5737

<PAGE>

21.  Governing Law and Injunctive Relief
     It is the desire and intention of the parties to specify that the general
     maritime law of the United States of America shall govern the
     interpretation, construction and enforcement of this Agreement and the
     rights of the parties under this Agreement and any amendments hereto;
     provided, however, to the extent said maritime law cannot be applied, this
     Agreement shall otherwise be interpreted according to the laws of the State
     of Texas, excluding any choice of law rule thereof that would direct the
     application of the laws of any other jurisdiction. In addition, either
     party may apply for injunctive relief in any court of competent
     jurisdiction to restrain the breach, or threatened breach, of this
     Agreement. Venue for any injunctions or other lawsuits related to this
     Agreement is limited to the Courts of Harris County, Texas.

22.  Disclaimer
     BY REASON OF ITS KNOWLEDGE AND EXPERIENCE IN THE EVALUATION, ACQUISITION,
     AND OPERATION OF OIL AND GAS PROPERTIES, RIDGEWOOD HAS EVALUATED THE MERITS
     AND RISKS OF ENTERING INTO THIS AGREEMENT AND HAS FORMED AN OPINION BASED
     SOLELY ON RIDGEWOOD's KNOWLEDGE AND EXPERIENCE AND NOT ON ANY
     REPRESENTATIONS OR WARRANTIES BY DEVON. RIDGEWOOD HAS RELIED SOLELY ON ITS
     INDEPENDENT INVESTIGATION OF, AND JUDGMENT WITH RESPECT TO THE INTERESTS
     AND THE ADVICE OF ITS OWN LEGAL, TAX, ECONOMIC, ENVIRONMENTAL, ENGINEERING,
     GEOLOGICAL AND GEOPHYSICAL ADVISORS AND NOT ON ANY COMMENTS OR STATEMENTS
     OF ANY REPRESENTATIVES OF, OR CONSULTANTS OR ADVISORS ENGAGED BY DEVON.
     RIDGEWOOD FURTHER REPRESENTS THAT IT HAS NOT RELIED AND WILL NOT RELY ON
     ANY STATEMENTS BY DEVON OR ITS REPRESENTATIVES IN MAKING ITS DECISION TO
     ENTER INTO THIS AGREEMENT.

23.  Force Majeure
     All obligations imposed by this Agreement on each party, except for the
     payment of money, shall be suspended and all periods of time for exercising
     any rights hereunder shall be extended while compliance is prevented, in
     whole or in part, by a labor dispute, fire, food, war, civil disturbance,
     terrorist acts, storms, hurricanes, or other acts of God, by laws, by
     governmental rules, regulations, or orders, by governmental action or
     governmental delay, inability to secure materials, or by any other cause,
     whether similar or dissimilar, beyond the reasonable control of the
     affected party; provided, however, that performance shall be resumed within
     a reasonable time after such cause has been removed; and provided further
     that no party shall be required against its will to settle any labor
     dispute.
24. Confidentiality
     Ridgewood shall not disclose any of the terms or provisions of this
     Agreement to any third parties in the absence of Devon's prior written
     approval; provided, Ridgewood shall be entitled to disclose the terms
     hereof without Devon's prior written consent to such of the following
     persons who have a clear need to know the terms and provisions hereof and
     who have agreed in writing to be bound by the confidentiality obligations
     of this Article 24:

     (i)   employees, officers and directors of Ridgewood;

<PAGE>

     (ii)  any professional consultant or agent retained by f Ridgewood or
           the purpose of evaluating the Contract Area, or any operations to
           be conducted under the terms of this Agreement; and/or

     (iii) any bank financing Ridgewood's participation in this Agreement,
           including any professional consultant retained by such bank for
           such purpose.

25.  Statements and Releases
     Notwithstanding the provisions of Article 24, Confidentiality above,
     neither party shall issue any news release or make any public announcement
     relating to the subject matter of this Agreement without the prior approval
     of the other party, which approval shall not be unreasonably withheld;
     provided, however, that such prior approval shall not be required in the
     event that a party is compelled to issue a release or announcement by
     applicable law, order, decree, regulation or rule, including without
     limitation those of any regulatory agency, securities commission, stock
     exchange, judicial or administrative proceeding, but in such event the
     affected party shall use its best reasonable efforts to give the other
     party at least forty-eight (48) hours advance notice of the content of such
     release. Notwithstanding the foregoing, Ridgewood shall not make any public
     announcement or statement concerning any of the terms of this Agreement or
     any of the operations to be conducted hereunder in the absence of Devon's
     prior approval first obtained.

26.  Confidential Data
     Neither party shall release any geological, geophysical or reservoir
     information or any logs or other information pertaining to the progress,
     tests or results of any well ("Confidential Data") covered by this
     Agreement unless agreed to by all parties hereto, except for necessary
     disclosures to governmental agencies or under the rules of a stock exchange
     on which the stock of any party is publicly traded; provided, however, that
     anyone may make Confidential Data available to (i) reputable geological
     consulting firms or engineering firms and gas transmission companies for
     hydrocarbon reserve and other technical evaluations; (ii) reputable and
     financially responsible third parties with whom a party is engaged in bona
     fide negotiations for the sale, farmout or other disposition of all or a
     portion of its interest in the Contract Area; and (iii) to reputable
     financial institutions for study prior to commitment of funds. The
     Confidential Data made available shall not be removed from the custody or
     premises of the party making such data available. Any party permitted such
     access shall first agree in writing neither to disclose such data to others
     nor to use such data except for the purpose for which it is disclosed.
     Also, except for their being bound by the confidentiality obligation, there
     shall be no requirement for approval with respect to access of information
     to subsidiaries, parent or affiliated companies of the parties. The
     obligations and restrictions contained in this Article with respect to the
     Confidential Data shall survive the term of this Agreement.

27.  Preferential Right to Purchase
     In the event Ridgewood has earned an interest in the Contract Area as above
     prescribed, and either party ("Disposing Party") desires to transfer, sell,
     farmout, assign, exchange, or otherwise dispose of all or part of its
     interest in the Contract Area, it shall promptly give written notice to the
     other party with full information about the proposed transaction,
     including, but not limited to, the name and address of the prospective
     transferee (who must be ready, willing, and able to acquire the interest
     and deliver the stated consideration therefor), the consideration for the
     transfer, farmout terms, and all other terms of the offer.

<PAGE>

     In the case of a package sale of oil and gas interests that includes all or
     part of the Disposing Party's working interest in the Contract Area, or if
     the proposed transaction is structured as a non-simultaneous, like-kind
     exchange under Section 1031 of the Internal Revenue Code of 1986, as
     amended ("Code"), the working interest that is subject to this preferential
     right shall be separately valued and the notice shall state the cash value
     or other terms attributed to the interest by the prospective transferee.
     The other party shall then have an optional prior right, for a period of
     thirty (30) days after receipt of the notice, to elect to purchase or
     acquire on the same terms and conditions, or on equivalent terms of a
     non-cash transaction, all of the working interest that the Disposing Party
     is proposing to transfer. If this preferential right is exercised by a
     party, the purchasing or acquiring party shall share the purchased or
     acquired interests in the proportions that the working interest of the
     acquiring party bears to the total working interest of all acquiring
     parties, or in such proportions as the acquiring parties otherwise agree.
     This preferential right shall apply separately to each working interest or
     part thereof covered by this Agreement, regardless of whether it is
     included in the proposed transaction along with other oil and gas
     interests, whether as a sale, farmout, or non-simultaneous, like-kind
     exchange. Upon exercise of this preferential right, the acquiring party
     shall agree to perform all obligations of the prospective transferee under
     the proposed transaction for the working interest subject to the proposed
     transaction. This preferential right, however, shall not exist or apply
     when a party proposes (a) to mortgage its interest; (b) to dispose of or
     transfer its interest by merger, reorganization, consolidation; (c) to sell
     all or substantially all of its assets to a subsidiary or parent company or
     to a subsidiary of a parent company, or to any company in which the
     foregoing owns a majority of the stock; (d) to sell all or substantially
     all of its Gulf of Mexico assets; or (e) to merge with another entity, so
     long as the party is the surviving entity. If the proposed transaction is
     not consummated within six (6) months after receipt of the notice by the
     other party, the working interest shall again be subject to the
     preferential purchase right under this 26.

28.  Entire Agreement
     This Agreement embodies the entire agreement between Devon and Ridgewood
     and supersedes all prior agreements and understandings relating to the
     subject matter hereof whether oral or written, including, but not limited
     to that certain letter agreement dated June 16, 2005, between Devon and
     Ridgewood. This Agreement may be amended only by mutual acceptance of
     instruments in writing executed by both Devon and Ridgewood and may be
     supplemented only by documents delivered or to be delivered in accordance
     with the express terms hereof.

29.  Term
     Subject to the continuing obligations under Article 26, Confidential Data,
     above, this Agreement will terminate without cost or penalties in the event
     that (i) upon Ridgewood's failure to earn any interest in the Contract Area
     under the terms of this Agreement, or (ii) upon Ridgewood's failure to
     remedy any material breach of this Agreement after thirty (30) days advance
     written notice from Devon, or (iii) upon cessation of production of from
     the Contract Area as prescribed in Article 16, Reassignment on Cessation of
     Production, above, or (iv) by mutual agreement of the parties. Provided,
     any such termination of this Agreement shall not operate to relieve
     Ridgewood of the obligations theretofore incurred by it under the terms of
     this Agreement.

<PAGE>

30.  Conflicts - Agreement / Exhibits
     If there is a conflict between this Agreement and the Exhibits attached
     hereto, the terms and conditions of this Agreement shall prevail. If there
     is a conflict between the JOA and the PHA, the terms and conditions of the
     PHA shall prevail.

     If the above and foregoing, together with the Exhibits attached hereto,
correctly set forth and evidence the agreement and understanding between the
parties, please sign one (1) duplicate original of this Agreement below and
return same to the undersigned by 5:00 P.M. (CT), on September 20, 2005. If
Ridgewood has not unconditionally accepted and returned this Agreement fully
executed by such date, then this AMI and Participation Agreement shall
automatically terminate and be of no force or effect as an Agreement, contract,
offer or for any purpose.

Devon Energy Production Company, L.P.

By: /s/ Mark Gress                          Date: 9-15-05
    ------------------------------               --------
        Mark K. Gress
        Agent and Attorney-in-Fact

Ridgewood Energy Corporation

By: W. G. Tabor                             Date: 9-15-05
    ---------------------------                   --------
Name: W. Greg Tabor
      -------------------------
Title: Executive Vice President
      -------------------------

<PAGE>

                                [GRAPHIC OMITTED]

                                   EXHIBIT "A"
                             EUGENE ISLAND BLOCK 337

                                   OCS-G-03332

     Attached to and made a part of that certain Participation Agreement by
         and between Devon Energy Production Company, L.P. and Ridgewood
                               Energy Corporation

<PAGE>

                 [GRAPHIC OMMITED]                          Exhibit "B"
               AUTHORITY FOR EXPENDITURE         Attached  to  and  made a part
                  ORIGINAL AFE                of  that  certain   Participation
                                                 Agreement by and between Devon
                                   Energy Production Company, L.P. and Ridgewood
                                                     Energy Corporation
--------------------------------------------------------------------------------
WORK TYPE Dev. Drig & Compl - Type 11 (Operated)
          --------------------------------------
OBJECTIVE EI 337 A010 Drill Mercury Prospect
          --------------------------------------
              AFE NO. 119917                              DATE May 04, 2005
              COMPANY DEPCO
              OPERATOR DEPCO
--------------------------------------------------------------------------------
 LEASE/WELL NAME El 337 A010                   LEASEMIELL NO. 300082-018
           FIELD El - Eugene Island                 DUE DATE September 15, 2005
       DIVISION GULF DIVISION                 EST START DATE July 01, 2005
       DISTRICT OFFSHORE SHELF                   PREPARED BY Hargrove, Susan
         STATE Gulf Of Mexico                   PHONE/FAX NO. 713-286-5832

AFE DESCRIPTION

     Drill and evaluate a 16,300' MD / 12,860' TVD well to test the IC and
     Lentic Sands from the El 337'A' platform.

     Completion costs are covered under AFE 120495
JUSTIFICATION
Original AFE
    N/A

WORKING INTEREST INFORMATION - ORIGINAL AFE

Working Interest Owners        Decimal interest         Amount
--------------------------------------------------------------------------
DEPCO                                34.000000%         $4,065,380.00
Forest Oil Corporation               22.000000%         $2,630,540.00
Ridgewood Energy Partnershi          44.000000%         $5,261,080.00
--------------------------------------------------------------------------
Total                               100.000000%        $11,957,000.00
--------------------------------------------------------------------------

                                Amount Approved
                          Gross            Devon Net
  --------------------------------------------------------
  Original AFE         $11,957,000.00      $4,065,380.00
  --------------------------------------------------------
  Total AFE            $11,957,000.00      $4,065,380.00
  --------------------------------------------------------

APPROVAL INFORMATION

1 DEPCO

 [ILLEGIBLE SIGNATURE]                                  07/21/2005
 ------------------------------------------------------------------
 Senior VP Marketing                                    Date

 [ILLEGIBLE SIGNATURE]                                   07/21/2005
 ------------------------------------------------------------------
 Vice President and General Manager,                    Date
 Exploration

 [ILLEGIBLE SIGNATURE]                                   07/21/2005
 ------------------------------------------------------------------
 Well Engineering Manager                               Date

 [ILLEGIBLE SIGNATURE]                                   07/21/2005
 ------------------------------------------------------------------
 Manager Production/Operations - Gulf                   Date

-------------------------------------------------------------------
 Forest Oil Corporation      22.000000%     $ 2,630,540.00    Date

-------------------------------------------------------------------
 Ridgewood Energy Partnershi 44.000000% $ 5,261,080.00 Date

   9/15/2005

<PAGE>

--------------------------------------------------------------------------------
WORK TYPE Dev. Drig & Compl - Type 11 (Operated)
          --------------------------------------
OBJECTIVE EI 337 A010 Drill Mercury Prospect
          --------------------------------------
              AFE NO. 119917                              DATE May 04, 2005
              COMPANY DEPCO
              OPERATOR DEPCO
--------------------------------------------------------------------------------

 [ILLEGIBLE SIGNATURE]                                  07/01/2005
 ------------------------------------------------------------------
 Land Manager - Gulf Division                           Date

 [ILLEGIBLE SIGNATURE]                                  06/30/2005
 ------------------------------------------------------------------
 Supervisor Exploitation - Gulf                         Date

 [ILLEGIBLE SIGNATURE]                                  06/29/2005
 ------------------------------------------------------------------
 Well Engineering Completion Supervisor                 Date

 [ILLEGIBLE SIGNATURE]                                  06/29/2005
 ------------------------------------------------------------------
 Well Engineering Operations Supervisor                 Date

 [ILLEGIBLE SIGNATURE]                                  07/11/2005
 ------------------------------------------------------------------
 Director, Deepwater Well Engineering &                 Date
 Facilities

 [ILLEGIBLE SIGNATURE]                                  07/29/2005
 ------------------------------------------------------------------
 President                                              Date

 [ILLEGIBLE SIGNATURE]                                  07/29/2005
 ------------------------------------------------------------------
 Sr. Vice President Exploration &                       Date
 Production

   9/15/2005

<PAGE>

                                  Exhibit "B"

                                      Devon
                             EUGENE ISLAND Blk 337
                             OCS-G 03332. Well A10

                      [ILLEGIBLE TABLE] [GRAPHIC OMITTED]

<PAGE>

                                  Exhibit "B"

     Mercury Prospect El 337

     Projected Spud Date:

            Late 3rd Quarter/4th Quarter 2005

     Footage Calls

               Surface Location    1929' FSL, 6516' FWL       El 337
               IC Sand Target      4470' FSL, 4290' FWL       El 337
               L-1 Sand            8413' FSL, 834' FWL        El 337
               TD                  8661' FSL, 617' FWL        El 337

     Drilling AFE:

               Attached (8/8ths cost: $11,957 MM)

     Completion AFE:

               Completion costs included on Drilling AFE (attached) (8/8ths
               cost: $4,786 MM)
               This cost could be substantially lower if completion is possible
               with lower cost Sundowner type rig

      Well Plan:

               Attached

      Logging Program:

               Standard contract mudlogging program from from casing point at
               4164' MD to 16,299' MD covering IC Sand and L-1 through L-5 Sand
               intervals

               Logging while drilling (LWD with OR,, RES) fom surface casing Q
               4164' MD to 16.299' MD.

               Triple combo (OR, RES, NEU/DEN) from casing point at 12,196' MD
               to 16,299' MD covering Lentic L-1 through L-5 Sand interval.

               Contingency: Triple combo (GR, RES, NEU/DEN) fom surface casing
               (R) 4164' MD to casing point at 8491' MD covering IC Sand
               interval if judged to be productive based on LWD analysis.

               No full cores or SWC program planned

<PAGE>

                                [GRAPHIC OMITTED]
                            AUTHORITY FOR EXPENDITURE
                                  ORIGINAL AFE
--------------------------------------------------------------------------------
WORK TYPE Dev. Drig & Compl - Type 11 (Operated)
          --------------------------------------
OBJECTIVE EI 337 A010 Complete Mercury Prospect
          --------------------------------------
              AFE NO. 120495                                 DATE June 07, 2005
              COMPANY DEPCO
              OPERATOR DEPCO
--------------------------------------------------------------------------------
 LEASE/WELL NAME El 337 A010                    LEASEMIELL NO. 300082-018
           FIELD El - Eugene Island                  DUE DATE September 16, 2005
       DIVISION GULF DIVISION                  EST START DATE July 01, 2005
       DISTRICT OFFSHORE SHELF                    PREPARED BY Hargrove, Susan
          STATE Florida                         PHONE/FAX NO. 713-286-5832

AFE DESCRIPTION

     Complete as a single Lentic frac pack in the 16,300' MD / 12,860' TVD well
     from the El 337'A' platform.

     Drill AFE is 119917.
JUSTIFICATION
Original AFE
     N/A

   WORKING INTEREST INFORMATION - ORIGINAL AFE

Working Interest Owners        Decimal interest         Amount
--------------------------------------------------------------------------
DEPCO                                50.000000%         $2,393,250.00
Forest Oil Corporation               17.000000%           $813,705.00
Ridgewood Energy Partnershi          33.000000%         $1,579,545.00
--------------------------------------------------------------------------
Total                               100.000000%         $4,786,500.00
--------------------------------------------------------------------------

                                Amount Approved
                          Gross            Devon Net
  --------------------------------------------------------
  Original AFE         $4,786,500.00      $2,393,250.00
  --------------------------------------------------------
  Total AFE            $4,786,500.00      $2,393,250.00
  --------------------------------------------------------

APPROVAL INFORMATION

     1 DEPCO

 [ILLEGIBLE SIGNATURE]                                  07/21/2005
 ------------------------------------------------------------------
 Vice President and General Manager,                    Date
 Exploration

 [ILLEGIBLE SIGNATURE]                                  07/01/2005
 ------------------------------------------------------------------
 Well Engineering Manager                               Date

 [ILLEGIBLE SIGNATURE]                                  07/12/2005
 ------------------------------------------------------------------
 Manager Production/Operations - Gulf                   Date

 [ILLEGIBLE SIGNATURE]                                  07/01/2005
 ------------------------------------------------------------------
 Land Manager - Gulf Division                           Date

 ------------------------------------------------------------------
 Forest Oil Corporation      17.000000%      $ 813,705.00     Date

 ------------------------------------------------------------------
 Ridgewood Energy Partnershi 33.000000%     $ 1,579.545.00    Date

  9/16/2005

<PAGE>

--------------------------------------------------------------------------------
WORK TYPE Dev. Drig & Compl - Type 11 (Operated)
          --------------------------------------
OBJECTIVE EI 337 A010 Complete Mercury Prospect
          --------------------------------------
              AFE NO. 120495                                 DATE June 07, 2005
              COMPANY DEPCO
              OPERATOR DEPCO
--------------------------------------------------------------------------------

 [ILLEGIBLE SIGNATURE]                                  06/30/2005
 ------------------------------------------------------------------
 Supervisor Exploitation - Gulf                         Date

 [ILLEGIBLE SIGNATURE]                                  06/30/2005
 ------------------------------------------------------------------
 Well Engineering Completion Supervisor                 Date

 [ILLEGIBLE SIGNATURE]                                  07/01/2005
 ------------------------------------------------------------------
 Well Engineering Operations Supervisor                 Date

 [ILLEGIBLE SIGNATURE]                                  07/12/2005
 ------------------------------------------------------------------
 Director, Deepwater Well Engineering &                 Date
 Facilities

  9/16/2005

<PAGE>

-------------------------------------------------------------------------------
WORK TYPE Dev. Drig & Compl - Type 11 (Operated)
          --------------------------------------
OBJECTIVE EI 337 A010 Complete Mercury Prospect
          --------------------------------------
              AFE NO. 120495                                 DATE June 07, 2005
              COMPANY DEPCO
              OPERATOR DEPCO
--------------------------------------------------------------------------------

COST DETAIL INFORMATION

     ORIGINAL AFE DETAIL
<TABLE>
<CAPTION>

       Account                 Intangible                Gross Drilling         Gross Compl    Gross P&A        TOTAL
     Gen    Sub           Account Description                Costs                Costs          Costs     ORIGINAL COSTS
-------------------------------------------------------------------------------------------------------------------------
<S>  <C>    <C>            <C>                                             <C>                           <C>
     216    043            DAYWORK                                         $   1,750,300.00              $   1,750,300.00
     216    102            COMPLETION FLUIDS                               $     625,100.00              $     625,100.00
     216    103            SURFACE RENTAL TOOLS &                          $      41,800.00              $      41,800.00
     216    104            DOWNHOLE RENTAL TOOLS &                         $      41,400.00              $      41,400.00
     216    109            OTHER MATERIALS & SUPPLIES                      $       5,000.00              $       5,000.00
     216    201            WELDING, ROUSTABOUTS & OTHER                    $      17,500.00              $      17,500.00
     216    203            TRUCKING & HOTSHOT                              $      23,000.00              $      23,000.00
     216    251            CEMENT & CEMENTING SERVICES                     $     118,000.00              $     118,000.00
     216    254            FLOWBACK EQUIPMENT TESTING                      $      28,000.00              $      28,000.00
     216    255            LOGGING                                         $     127,000.00              $     127,000.00
     216    259            CASING & TUBULAR SERVICES                       $      88,000.00              $      88,000.00
     216    265            STIMULATION & GRAVEL PACK                       $     203,000.00              $     203,000.00
     216    266            HELICOPTER TRANSPORTATION                       $      80,500.00              $      80,500.00
     216    267            MARINE TRANSPORTATION                           $     241,500.00              $     241,500.00
     216    269            CONSULTANTS                                     $      23,000.00              $      23,000.00
     216    281            COMMUNICATIONS SERVICES                         $       5,900.00              $       5,900.00
     216    306            OTHER POWER & FUEL                              $     165,600.00              $     165,600.00
     216    559            ENVMNT & SAFETY                                 $      42,800.00              $      42,800.00
     216    711            COMPANY SUPERVISION                             $      42,600.00              $      42,600.00
     216    865            COMPANY BENEFITS                                $      14,300.00              $      14,300.00
-------------------------------------------------------------------------------------------------------------------------
     TOTAL  Intangible - ORIGINAL AFE                        $0.00         $    3,684,300.00   $0.00     $   3,684,300.00
-------------------------------------------------------------------------------------------------------------------------
       Account                       P&A                  Gross Drilling        Gross Compl      Gross P&A       TOTAL
     Gen    Sub              Account Description             Costs                Costs            Costs   ORIGINAL COSTS
-------------------------------------------------------------------------------------------------------------------------
     TOTAL P&A - ORIGINAL AFE                                $0.00         $           0.00    $0.00     $          0.00
-------------------------------------------------------------------------------------------------------------------------
       Account                    Tangible                Gross Drilling   Gross Compl         Gross P&A         TOTAL
     Gen    Sub              Account Description             Costs             Costs            Costs      ORIGINAL COSTS
-------------------------------------------------------------------------------------------------------------------------
     217    911   LINER                                                    $     346,500.00              $     346,500.00
     217    915  TUBING                                                    $     237,600.00              $     237,600.00
     217    925  SUBSURFACE EQUIP                                          $     365,200.00              $     365,200.00
     217    931  WELLHEAD VALVES & EQUIPMENT                               $     125,400.00              $     125,400.00
     217    961  LINE PIPE,METERS & FITTINGS                               $      27,500.00              $      27,500.00
-------------------------------------------------------------------------------------------------------------------------
     TOTAL Tangible - ORIGINAL AFE                           $0.00         $   1,102,200.00    $0.00     $   1,102,200.00
-------------------------------------------------------------------------------------------------------------------------

     Gross Total ORIGINAL AFE Costs                          $0.00         $   4,786,500.00    $0.00     $   4,786,500.00
-------------------------------------------------------------------------------------------------------------------------

     Gross Grand Total AFE Costs                             $0.00        $    4,786,500.00    $0.00     $   4,786,500.00
-------------------------------------------------------------------------------------------------------------------------
</TABLE>

<PAGE>

30.  Conflicts - Agreement I Exhibits

     If there is a conflict between this Agreement and the Exhibits attached
     hereto, the terms and conditions of this Agreement shall prevail. If there
     is a conflict between the JOA and the PHA, the terms and conditions of the
     PHA shall prevail,

     If the above and foregoing, together with the Exhibits attached hereto,
correctly set forth and evidence the agreement and understanding between the
parties, please sign one (1) duplicate original of this Agreement below and
return same to the undersigned by 5:00 P.M. (CT), on September 20, 2005. If
Ridgewood has not unconditionally accepted and returned this Agreement fully
executed by such date, then this AMI and Participation Agreement shall
automatically terminate and be of force or effect as an Agreement, contract,
offer or for any purpose.

Devon Energy Production Company, L.P.

By: /s/ Mark Gress                          Date: 9-15-05
    -----------------------                       --------
        Mark K. Gress
        Agent and Attorney-in-Fact

Ridgewood Energy Corporation

By: [ILLEGIBLE SIGNATURE]                    Date:
    --------------------                          --------
Name:
      ------------------
Title:
      ------------------

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00102-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00102-of-00352.parquet"}]]