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                                                                   EXHIBIT 4.D.1

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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
              CHASE BANK OF TEXAS, NATIONAL ASSOCIATION, AS TRUSTEE

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

                          NINTH SUPPLEMENTAL INDENTURE

                          DATED AS OF NOVEMBER 27, 2002

                                       TO

                                    INDENTURE

                            DATED AS OF MAY 27, 1999

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

              10 3/8% SENIOR SUBORDINATED NOTES DUE 2009, SERIES A
              10 3/8% SENIOR SUBORDINATED NOTES DUE 2009, SERIES B

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                          NINTH SUPPLEMENTAL INDENTURE

         THIS NINTH SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"),
dated as of November 27, 2002 is by and among El Paso Energy Partners, L.P., a
Delaware limited partnership (formerly Leviathan Gas Pipeline Partners, L.P.)
(the "Partnership"), El Paso Energy Partners Finance Corporation, a Delaware
corporation (formerly Leviathan Finance Corporation), the guarantor parties
hereto, and JPMorgan Chase Bank, a New York state banking corporation, as
successor trustee to the Chase Bank of Texas, National Association, as Trustee.

                              W I T N E S S E T H:

         WHEREAS, the Issuers, the Subsidiary Guarantors and the Trustee entered
into an Indenture, dated as of May 27, 1999 (as in effect on the date hereof,
the "Indenture"), relating to the 10 3/8% Senior Subordinated Notes due 2009,
Series A and the 10 3/8% Senior Subordinated Notes due 2009, Series B;

         WHEREAS, the Partnership desires to designate El Paso South Texas,
L.P., a Delaware limited partnership (the "NEW GUARANTOR"), as a Restricted
Subsidiary and, accordingly, cause such subsidiary to 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 and 11.01 of the Indenture;

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

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

         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, the Issuers, the Subsidiary Guarantors and the Trustee
mutually covenant and agree for the equal and proportionate benefit of all
Holders of the Notes 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.

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                       SECTION 2. SUPPLEMENTAL PROVISIONS

         2.1      UNCONDITIONAL GUARANTEE. Subject to the provisions of Article
11 of the Indenture, the New Guarantor shall be a Subsidiary Guarantor under the
terms of the Indenture and hereby, jointly and severally with the other
Subsidiary Guarantors, unconditionally guarantees 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
Guarantor hereby agrees that to the fullest extent permitted by applicable law,
its 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. To the
fullest extent permitted by applicable law, the New Guarantor hereby waives
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 whatsoever
and covenants 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 Guarantor agrees that it 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 Guarantor further agrees 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

                                       2

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payable by the Subsidiary Guarantors for the purpose of these Guarantees. The
New Guarantor agrees 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 Guarantor hereby confirms,
adopts and acknowledges 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 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 Issuers 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.

            [THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK.]

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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/ Keith Forman                      By:    /s/ Keith Forman
       -----------------------------------          ----------------------------
Name:  Keith Forman                          Name:  Keith Forman
Title: Vice President and Chief Financial    Title: Vice President and Chief
       Officer                                      Financial Officer

JP MORGAN CHASE BANK, as successor trustee

By:    /s/ Cary W. Gilliam
       -------------------------------
Name:  Cary W. Gilliam
Title: Vice President

NEW GUARANTOR:

EL PASO SOUTH TEXAS, L.P.
   By: El Paso Energy Partners Oil Transport, L.L.C., its general partner

By:    /s/ Keith Forman
       ---------------------------------
Name:  Keith Forman
Title: Vice President and Chief Financial Officer

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

                  ARGO, L.L.C.*
                  ARGO I, L.L.C.*
                  ARGO II, L.L.C.*
                  CRYSTAL HOLDING, L.L.C.*
                  CHACO LIQUIDS PLANT TRUST
                    By:EL PASO ENERGY PARTNERS OPERATING COMPANY, L.L.C., in
                       its capacity as trustee of the Chaco Liquids Plant Trust*
                  DELOS OFFSHORE COMPANY, L.L.C.*
                  EAST BREAKS GATHERING COMPANY, L.L.C.
                    By: EL PASO ENERGY PARTNERS DEEPWATER, L.L.C., its sole
                        member*
                  EL PASO ENERGY INTRASTATE, L.P.*
                  EL PASO ENERGY PARTNERS DEEPWATER, L.L.C.*
                  EL PASO ENERGY PARTNERS OIL TRANSPORT, L.L.C.*
                  EL PASO ENERGY PARTNERS OPERATING COMPANY, L.L.C.*
                  EL PASO ENERGY WARWINK I COMPANY, L.P.*
                  EL PASO ENERGY WARWINK II COMPANY, L.P.*
                  EL PASO HUB SERVICES COMPANY, L.L.C.*
                  EL PASO INDIAN BASIN, L.P.*
                  EL PASO OFFSHORE GATHERING & TRANSMISSION, L.P.*
                  EL PASO SOUTH TEXAS, L.P.*
                  EPGT TEXAS PIPELINE, L.P.*
                  EPN GATHERING AND TREATING COMPANY, L.P.*
                  EPN GATHERING AND TREATING GP HOLDING, L.L.C.*
                  EPN GP HOLDING, L.L.C.*
                  EPN GP HOLDING I, L.L.C.*
                  EPN HOLDING COMPANY, L.P.*
                  EPN HOLDING COMPANY I, L.P.*
                  EPN NGL STORAGE, L.L.C.*
                  EPN PIPELINE GP HOLDING, L.L.C.*
                  FIRST RESERVE GAS, L.L.C.*
                  FLEXTREND DEVELOPMENT COMPANY, L.L.C.*
                  GREEN CANYON PIPE LINE COMPANY, L.P.*
                  HATTIESBURG GAS STORAGE COMPANY*
                  HATTIESBURG INDUSTRIAL GAS SALES, L.L.C.*
                  HIGH ISLAND OFFSHORE SYSTEM, L.L.C.
                    By: EL PASO ENERGY PARTNERS DEEPWATER, L.L.C., its sole
                        member*
                  MANTA RAY GATHERING COMPANY, L.L.C.*
                  PETAL GAS STORAGE, L.L.C.*
                  POSEIDON PIPELINE COMPANY, L.L.C.*
                  VK DEEPWATER GATHERING COMPANY, L.L.C.*

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                  VK-MAIN PASS GATHERING COMPANY, L.L.C.*
                  WARWINK GATHERING AND TREATING COMPANY*

                  *By:   /s/ Keith Forman
                         ---------------------------------------
                  Name:  Keith Forman
                  Title: Vice President and Chief Financial Officer