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                          EL PASO ENERGY PARTNERS, L.P.
          EL PASO ENERGY PARTNERS FINANCE CORPORATION, AS THE ISSUERS,

                                       AND

             THE SUBSIDIARIES PARTY HERETO, AS SUBSIDIARY GUARANTORS

                                       AND

           JPMORGAN CHASE BANK, A NEW YORK STATE BANKING CORPORATION,
                             AS SUCCESSOR TRUSTEE TO
   THE CHASE MANHATTAN BANK, A NEW YORK STATE BANKING CORPORATION, AS TRUSTEE

                              --------------------

                          FIRST SUPPLEMENTAL INDENTURE

                           DATED AS OF APRIL 18, 2002

                                       TO

                                    INDENTURE

                            DATED AS OF MAY 17, 2001

                              --------------------

               8 1/2% SERIES A SENIOR SUBORDINATED NOTES DUE 2011
               8 1/2% SERIES B SENIOR SUBORDINATED NOTES DUE 2011





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                          FIRST SUPPLEMENTAL INDENTURE

         THIS FIRST SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"),
dated as of April 18, 2002 is by and among El Paso Energy Partners, L.P., a
Delaware limited partnership, El Paso Energy Partners Finance Corporation, a
Delaware corporation (formerly Leviathan Finance Corporation), the guarantor
parties hereto, and JPMorgan Chase Bank, successor to The Chase Manhattan Bank,
a New York state banking corporation, as trustee.

                                   WITNESSETH:

         WHEREAS, the Issuers (as defined in the Indenture), the Subsidiary
Guarantors (as defined in the Indenture) and the Trustee (as defined in the
Indenture) entered into an Indenture, dated as of May 17, 2001 (as in effect on
the date hereof, the "Indenture"), relating to the 8 1/2% Series A Senior
Subordinated Notes due 2011 and the 8 1/2% Series B Senior Subordinated Notes
due 2011;

         WHEREAS, on October 18, 2001 the Partnership (as defined in the
Indenture) acquired Deepwater Holdings, L.L.C., a Delaware limited liability
company ("Deepwater"), Western Gulf Holdings, L.L.C., a Delaware limited
liability company ("Western Gulf"), East Breaks Gathering Company, L.L.C., a
Delaware limited liability company ("East Breaks"), and High Island Offshore
System L.L.C., a Delaware limited liability company ("HIOS");

         WHEREAS, El Paso Energy Partners Deepwater, L.L.C., a Delaware limited
liability company and a Subsidiary Guarantor merged with Deepwater and Western
Gulf, with Western Gulf as the surviving entity expressly assuming the
obligations of the merged entities and thereafter changing its name to "El Paso
Energy Partners Deepwater, L.L.C." ("EP Deepwater");

         WHEREAS, on March 27, 2002 the Board of Directors of the General
Partner of the Partnership redesignated East Breaks and HIOS as Restricted
Subsidiaries under the Indenture;

         WHEREAS, the Partnership also acquired title to the Chaco Liquids Plant
Trust (the "Trust" and collectively with EP Deepwater, East Breaks and HIOS, the
"New Guarantors"), which will also become a Subsidiary Guarantor under the
Indenture pursuant to the terms of this Supplemental Indenture;

         WHEREAS, this Supplemental Indenture is executed and delivered pursuant
to Sections 4.14, 5.01, 11.01 and 11.04 of the Indenture;

         WHEREAS, the Issuers, the Subsidiary Guarantors (which term includes
the New Guarantors) and the Trustee desire to enter into this Supplemental
Indenture to provide for the New Guarantors' guarantee of payment on the same
terms and conditions as the Guarantees by the other Subsidiary Guarantors;

         WHEREAS, all conditions precedent provided for in the Indenture
relating to this Supplemental Indenture have been complied with; and

         NOW, THEREFORE, in consideration of the premises herein contained, and
for other good and valuable considerations, the receipt and sufficiency of which
are hereby acknowledged,
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the Issuers, the Subsidiary Guarantors and the Trustee mutually covenant and
agree for the equal and proportionate benefit of all Holders (herein defined) of
the Notes (herein defined) as follows:

               SECTION 1. INCORPORATION OF INDENTURE; DEFINITIONS

         1.1 INCORPORATION OF INDENTURE. This Supplemental Indenture constitutes
a supplement to the Indenture, and the Indenture and this Supplemental Indenture
shall be read together and shall have effect so far as practicable as though all
of the provisions thereof and hereof are contained in one instrument.

         1.2 DEFINITIONS. All capitalized terms used herein and not otherwise
defined herein shall have the respective meanings assigned to such terms in the
Indenture.

                       SECTION 2. SUPPLEMENTAL PROVISIONS

         2.1 UNCONDITIONAL GUARANTEE. Subject to the provisions of Article 11 of
the Indenture, the New Guarantors shall be Subsidiary Guarantors under the terms
of the Indenture and hereby unconditionally guarantee to each Holder of a Note
authenticated and delivered by the Trustee and to the Trustee and its successors
and assigns, irrespective of the validity and enforceability of the Indenture,
the Notes or the Obligations of the Issuers under the Indenture or the Notes,
that:

         (a)      the principal of, premium, interest and Liquidated Damages, if
                  any, on the Notes shall be promptly paid in full when due,
                  whether at the maturity or interest payment or mandatory
                  redemption date, by acceleration, redemption or otherwise, and
                  interest on the overdue principal of, premium, interest and
                  Liquidated Damages, if any, on the Notes, if any, if lawful,
                  and all other Obligations of the Issuers to the Holders or the
                  Trustee under the Indenture and the Notes shall be promptly
                  paid in full or performed, all in accordance with the terms of
                  the Indenture and the Notes; and

         (b)      in case of any extension of time of payment or renewal of any
                  Notes or any of such other obligations, that same shall be
                  promptly paid in full when due or performed in accordance with
                  the terms of the extension or renewal, whether at Stated
                  Maturity, by acceleration or otherwise. Failing payment when
                  due of any amount so guaranteed or any performance so
                  guaranteed for whatever reason, the Subsidiary Guarantors
                  shall be jointly and severally obligated to pay the same
                  immediately.

         The New Guarantors hereby agree that their obligations hereunder and
under the Indenture shall be unconditional, irrespective of the validity,
regularity or enforceability of the Notes or the Indenture, the absence of any
action to enforce the same, any waiver or consent by any Holder of the Notes
with respect to any provisions of the Indenture and the Notes, the recovery of
any judgment against the Issuers, any action to enforce the same or any other
circumstance which might otherwise constitute a legal or equitable discharge or
defense of a Subsidiary Guarantor. The New Guarantors hereby waive diligence,
presentment, demand of payment, filing of claims with a court in the event of
insolvency or bankruptcy of the Issuers, any right to require a proceeding first
against the Issuers, protest, notice and all demands

                                       2
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whatsoever and covenant that the Guarantees shall not be discharged except by
complete performance of the obligations contained in the Notes and the
Indenture.

         If any Holder or the Trustee is required by any court or otherwise to
return to the Issuers or Subsidiary Guarantors, or any custodian, trustee,
liquidator or other similar official acting in relation to either the Issuers or
Subsidiary Guarantors, any amount paid by either to the Trustee or such Holder,
these Guarantees, to the extent theretofore discharged, shall be reinstated in
full force and effect. The New Guarantors agree that they shall not be entitled
to any right of subrogation in relation to the Holders in respect of any
obligations guaranteed under the Indenture until payment in full of all
obligations guaranteed under the Indenture.

         The New Guarantors further agree that, as between the Subsidiary
Guarantors, on the one hand, and the Holders and the Trustee, on the other hand,
(x) the maturity of the Obligations guaranteed under the Indenture may be
accelerated as provided in Article 6 of the Indenture for the purposes of these
Guarantees, notwithstanding any stay, injunction or other prohibition preventing
such acceleration in respect of the obligations guaranteed under the Indenture,
and (y) in the event of any declaration of acceleration of such Obligations as
provided in Article 6 of the Indenture, such Obligations (whether or not due and
payable) shall forthwith become due and payable by the Subsidiary Guarantors for
the purpose of these Guarantees. The New Guarantors agree that the Subsidiary
Guarantors shall have the right to seek contribution from any non-paying
Subsidiary Guarantor so long as the exercise of such right does not impair the
rights of the Holders under these Guarantees.

         2.2 OTHER GUARANTEE TERMS. The New Guarantors hereby confirm, adopt and
acknowledge each of the provisions of the Indenture relating to the Subsidiary
Guarantors and the Guarantees, including, but not limited to, Articles 4 and 11
thereof.

                            SECTION 3. MISCELLANEOUS

         3.1 COUNTERPARTS. This Supplemental Indenture may be signed in
counterparts and by the different parties hereto in separate counterparts, each
of which shall constitute an original and all of which together shall constitute
one and the same instrument.

         3.2 SEVERABILITY. In case any provision in this Supplemental Indenture
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected or
impaired thereby.

         3.3 HEADINGS. The headings of the Sections of this Supplemental
Indenture have been inserted for convenience of reference only, are not to be
considered a part hereof and shall not modify or restrict any of the terms or
provisions hereof.

         3.4 SUCCESSORS. All agreements of the Issuers and the Subsidiary
Guarantors in this Supplemental Indenture shall bind their respective
successors. All agreements of the Trustee in this Supplemental Indenture shall
bind its successors.

         3.5 GOVERNING LAW. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT
GIVING EFFECT TO APPLICABLE

                                       3
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PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF
ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

         3.6 FULL FORCE AND EFFECT. The Indenture, as supplemented by this
Supplemental Indenture, remains in full force and effect and is hereby ratified
and confirmed as the valid and binding obligation of the parties hereto.

         3.7 TRUSTEE. The Trustee accepts the modifications of trusts referenced
in the Indenture and effected by this Supplemental Indenture. Without limiting
the generality of the foregoing, the Trustee assumes no responsibility for the
correctness of the recitals herein contained, which shall be taken as the
statements of the Company and the Subsidiary Guarantors, and the Trustee shall
not be responsible or accountable in any way whatsoever for or with respect to
the validity or execution or sufficiency of this Supplemental Indenture, and the
Trustee makes no representation with respect thereto.

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         IN WITNESS WHEREOF, the parties hereto have executed this Supplemental
Indenture as of the date first above written.


EL PASO ENERGY PARTNERS, L.P.                     EL PASO ENERGY PARTNERS
     by its general partner                       FINANCE CORPORATION
     EL PASO ENERGY PARTNERS
     COMPANY

By:    /s/ D. Mark Leland                         By:    /s/ D. Mark Leland
Name:  D. Mark Leland                             Name:  D. Mark Leland
Title: Senior Vice President                      Title: Senior Vice President


JPMORGAN CHASE BANK, as successor Trustee


By:    /s/ Mauri J. Cowen
Name:  Mauri J. Cowen
Title: Vice President and Trust Officer



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NEW GUARANTORS:

EL PASO ENERGY PARTNERS DEEPWATER, L.L.C.
(formerly, Western Gulf Holdings, L.L.C.)
EAST BREAKS GATHERING COMPANY, L.L.C.
HIGH ISLAND OFFSHORE SYSTEM, L.L.C.
THE CHACO LIQUIDS PLANT TRUST
(by EL PASO ENERGY PARTNERS OPERATING
COMPANY, L.L.C., solely in its capacity as trustee
of the Chaco Liquids Plant Trust)

By:    /s/ D. Mark Leland
Name:  D. Mark Leland
Title: Senior Vice President of each such entity






<PAGE>
Each of the undersigned hereby ratifies and confirms its respective obligations
under the Indenture, as supplemented by this Supplemental Indenture:

                              ARGO II, L.L.C.
                              CRYSTAL HOLDING, L.L.C.
                              CRYSTAL PROPERTIES AND TRADING COMPANY, L.L.C.
                              DELOS OFFSHORE COMPANY, L.L.C.
                              EL PASO ENERGY PARTNERS OIL TRANSPORT, L.L.C.
                              EL PASO ENERGY PARTNERS OPERATING COMPANY, L.L.C.
                              FIRST RESERVE GAS, L.L.C.
                              FLEXTREND DEVELOPMENT COMPANY, L.L.C.
                              GREEN CANYON PIPE LINE COMPANY, L.P.
                              HATTIESBURG INDUSTRIAL GAS SALES COMPANY, L.L.C.
                              MANTA RAY GATHERING COMPANY, L.L.C.
                              PETAL GAS STORAGE COMPANY, L.L.C.
                              POSEIDON PIPELINE COMPANY, L.L.C.
                              VK DEEPWATER GATHERING COMPANY, L.L.C.
                              VK-MAIN PASS GATHERING COMPANY, L.L.C.



                              By:    /s/ D. Mark Leland
                                  ---------------------------------------------
                              Name:  D. Mark Leland
                              Title: Senior Vice President of each such entity