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                                                                     EXHIBIT 4.3

                          FIRST SUPPLEMENTAL INDENTURE

         FIRST SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as
of May 7, 2003, by and among the entities listed on Schedule 1 attached hereto
(the "Guaranteeing Subsidiaries"), each being a subsidiary of Peabody Energy
Corporation (or its permitted successor), a Delaware corporation (the
"Company"), the Company, the other Subsidiary Guarantors (as defined in the
Indenture referred to herein) and US Bank National Association, as Trustee under
the Indenture referred to below (the "Trustee").

                                   WITNESSETH

         WHEREAS, the Company has heretofore executed and delivered to the
Trustee an Indenture (the "Indenture"), dated as of March 21, 2003 providing for
the issuance of an unlimited amount of 6-7/8% Notes due 2013 (the "Notes");

         WHEREAS, the Indenture provides that under certain circumstances the
Guaranteeing Subsidiaries shall execute and deliver to the Trustee a
supplemental indenture pursuant to which the Guaranteeing Subsidiaries shall
unconditionally guarantee all of the Company's Obligations under the Notes on
the terms and conditions set forth herein (the "Subsidiary Guarantee"); and

         WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the
Guaranteeing Subsidiaries and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

         1.       CAPITALIZED TERMS. Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

         2.       AGREEMENT TO GUARANTEE. The Guaranteeing Subsidiaries hereby
agree as follows:

                  (a)      Along with all Subsidiary Guarantors named in the
                           Indenture, to jointly and severally 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 Company hereunder or thereunder,
                           that:

                           (i)      the principal of and interest on the Notes
                                    will be promptly paid in full when due,
                                    whether at maturity, by acceleration,
                                    redemption or otherwise, and interest on the
                                    overdue

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                                    principal of and interest on the Notes, if
                                    any, if lawful, and all other obligations of
                                    the Company to the Holders or the Trustee
                                    hereunder or thereunder will be promptly
                                    paid in full or performed, all in accordance
                                    with the terms hereof and thereof; and

                           (ii)     in case of any extension of time of payment
                                    or renewal of any Notes or any of such other
                                    obligations, that same will 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. Each
                           Subsidiary Giarantor agrees that this is a guarantee
                           of payment and not a guarantee of collection.

                  (b)      The obligations hereunder shall be joint and several
                           and unconditional, irrespective of the validity or
                           enforceability of the Notes or the obligations of the
                           Company under 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 hereof or thereof, the recovery of any
                           judgment against the Company, 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.

                  (c)      The following is hereby waived: diligence,
                           presentment, demand of payment, filing of claims with
                           a court in the event of insolvency or bankruptcy of
                           the Company, any right to require a proceeding first
                           against the Company, protest, notice and all demands
                           whatsoever.

                  (d)      This Subsidiary Guarantee shall not be discharged
                           except by complete performance of the obligations
                           contained in the Notes and the Indenture.

                  (e)      If any Holder or the Trustee is required by any court
                           or otherwise to return to the Company, the Subsidiary
                           Guarantors, or any custodian, Trustee, liquidator or
                           other similar official acting in relation to either
                           the Company or the Subsidiary Guarantors, any amount
                           paid by either to the Trustee or such Holder, this
                           Subsidiary Guarantee, to the extent theretofore
                           discharged, shall be reinstated in full force and
                           effect.

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                  (f)      The Guaranteeing Subsidiaries shall not be entitled
                           to any right of subrogation in relation to the
                           Holders in respect of any obligations guaranteed
                           hereby until payment in full of all obligations
                           guaranteed hereby.

                  (g)      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
                           hereby may be accelerated as provided in Article 6 of
                           the Indenture for the purposes of this Subsidiary
                           Guarantee, notwithstanding any stay, injunction or
                           other prohibition preventing such acceleration in
                           respect of the obligations guaranteed hereby, 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 this
                           Subsidiary Guarantee.

                  (h)      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 the
                           Subsidiary Guarantee.

                  (i)      Pursuant to Section 10.04 of the Indenture, after
                           giving effect to any maximum amount and any other
                           contingent and fixed liabilities that are relevant
                           under any applicable Bankruptcy or fraudulent
                           conveyance laws, and after giving effect to any
                           collections from, rights to receive contribution from
                           or payments made by or on behalf of any other
                           Subsidiary Guarantor in respect of the obligations of
                           such other Subsidiary Guarantor under Article 10 of
                           the Indenture shall result in the obligations of such
                           Subsidiary Guarantor under Subsidiary Guarantee not
                           constituting a fraudulent transfer or conveyance.

         3.       EXECUTION AND DELIVERY. Each of the Guaranteeing Subsidiaries
agrees that the Subsidiary Guarantees shall remain in full force and effect
notwithstanding any failure to endorse on each Note a notation of such
Subsidiary Guarantee.

         4.       GUARANTEEING SUBSIDIARY MAY CONSOLIDATE, ETC. ON CERTAIN
TERMS.

                  (a)      The Guaranteeing Subsidiaries may not consolidate
                           with or merge with or into (whether or not such
                           Senior Subordinated Note Guarantor is the surviving
                           Person) another corporation, Person or entity whether
                           or not affiliated with such Subsidiary Guarantor
                           unless:

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                           (i)      subject to Section 10.04 of the Indenture,
                                    the Person formed by or surviving any such
                                    consolidation or merger (if other than a
                                    Subsidiary Guarantor or the Company)
                                    unconditionally assumes all the obligations
                                    of such Subsidiary Guarantor, pursuant to a
                                    supplemental Indenture in form and substance
                                    reasonably satisfactory to the Trustee,
                                    under the Notes, the Indenture and the
                                    Subsidiary Guarantee on the terms set forth
                                    herein or therein; and

                           (ii)     immediately after giving effect to such
                                    transaction, no Default or Event of Default
                                    exists.

                  (b)      In case of any such consolidation, merger, sale or
                           conveyance and upon the assumption by the successor
                           corporation, by supplemental Indenture, executed and
                           delivered to the Trustee and satisfactory in form to
                           the Trustee, of the Subsidiary Guarantee endorsed
                           upon the Notes and the due and punctual performance
                           of all of the covenants and conditions of the
                           Indenture to be performed by the Subsidiary
                           Guarantor, such successor corporation shall succeed
                           to and be substituted for the Subsidiary Guarantor
                           with the same effect as if it had been named herein
                           as a Subsidiary Guarantor. Such successor corporation
                           thereupon may cause to be signed any or all of the
                           Subsidiary Guarantees to be endorsed upon all of the
                           Notes issuable hereunder which theretofore shall not
                           have been signed by the Company and delivered to the
                           Trustee. All the Subsidiary Guarantees so issued
                           shall in all respects have the same legal rank and
                           benefit under the Indenture as the Subsidiary
                           Guarantees theretofore and thereafter issued in
                           accordance with the terms of the Indenture as though
                           all of such Subsidiary Guarantees had been issued at
                           the date of the execution hereof.

                  (c)      Except as set forth in Articles 4 and 5 of the
                           Indenture, and notwithstanding clauses (a) and (b)
                           above, nothing contained in the Indenture or in any
                           of the Notes shall prevent any consolidation or
                           merger of a Subsidiary Guarantor with or into the
                           Company or another Subsidiary Guarantor, or shall
                           prevent any sale or conveyance of the property of a
                           Subsidiary Guarantor as an entirety or substantially
                           as an entirety to the Company or another Subsidiary
                           Guarantor.

         5.       RELEASES.

                  (a)      In the event of a sale or other disposition of all of
                           the assets of any Subsidiary Guarantor, by way of
                           merger, consolidation or otherwise, or a sale or
                           other disposition of all to the capital stock of

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                           any Subsidiary Guarantor, then such Subsidiary
                           Guarantor (in the event of a sale or other
                           disposition, by way of merger, consolidation or
                           otherwise, of all of the capital stock of such
                           Subsidiary Guarantor) or the corporation acquiring
                           the property (in the event of a sale or other
                           disposition of all or substantially all of the assets
                           of such Subsidiary Guarantor) will be released and
                           relieved of any obligations under its Subsidiary
                           Guarantee; provided that the Net Proceeds of such
                           sale or other disposition are applied in accordance
                           with the applicable provisions of the Indenture,
                           including without limitation Section 4.10 of the
                           Indenture. Upon delivery by the Company to the
                           Trustee of an Officer's Certificate and an Opinion of
                           Counsel to the effect that such sale or other
                           disposition was made by the Company in accordance
                           with the provisions of the Indenture, including
                           without limitation Section 4.10 of the Indenture, the
                           Trustee shall execute any documents reasonably
                           required in order to evidence the release of any
                           Subsidiary Guarantor from its obligations under its
                           Subsidiary Guarantee.

                  (b)      Any Subsidiary Guarantor not released from its
                           obligations under its Subsidiary Guarantee shall
                           remain liable for the full amount of principal of and
                           interest on the Notes and for the other obligations
                           of any Subsidiary Guarantor under the Indenture as
                           provided in Article 10 of the Indenture.

         6.       NO RECOURSE AGAINST OTHERS. No past, present or future
director, officer, employee, incorporator, stockholder or agent of the
Guaranteeing Subsidiaries, as such, shall have any liability for any obligations
of the Company or any of the Guaranteeing Subsidiaries under the Notes, any
Subsidiary Guarantees, the Indenture or this Supplemental Indenture or for any
claim based on, in respect of, or by reason of, such obligations or their
creation. Each Holder of the Notes by accepting a Note waives and releases all
such liability. The waiver and release are part of the consideration for
issuance of the Notes. Such waiver may not be effective to waive liabilities
under the federal securities laws and it is the view of the Commission that such
a waiver is against public policy.

         7.       NEW YORK LAW TO GOVERN. THE LAW OF THE STATE OF NEW YORK SHALL
GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE.

         8.       COUNTERPARTS. The parties may sign any number of copies of
this Supplemental Indenture. Each signed copy shall be an original, but all of
them together represent the same agreement.

         9.       EFFECT OF HEADINGS. The Section headings herein are for
convenience only and shall not affect the construction hereof.

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         10.      THE TRUSTEE. The Trustee shall not be responsible in any
manner whatsoever for or in respect of the validity or sufficiency of this
Supplemental Indenture or for or in respect of the recitals contained herein,
all of which recitals are made solely by the Guaranteeing Subsidiaries and the
Company.

         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be executed by their respective officers thereunto duly authorized,
as of the date first written above.

PEABODY ENERGY CORPORATION                  US BANK NATIONAL ASSOCIATION
("COMPANY")                                 ("TRUSTEE")

By:__________________________________       By:_________________________________
Name:________________________________       Name:_______________________________
Title:_______________________________       Title:______________________________

EXISTING SUBSIDIARY GUARANTORS:

                                    AFFINITY MINING COMPANY
                                    ARID OPERATIONS INC.
                                    BEAVER DAM COAL COMPANY
                                    BIG RIDGE, INC.
                                    BIG SKY COAL COMPANY
                                    BLACK WALNUT COAL COMPANY
                                    BLUEGRASS COAL COMPANY
                                    CABALLO COAL COMPANY
                                    CHARLES COAL COMPANY
                                    CLEATON COAL COMPANY
                                    COAL PROPERTIES CORP.
                                    COLONY BAY COAL COMPANY
                                    COOK MOUNTAIN COAL COMPANY
                                    COTTONWOOD LAND COMPANY
                                    CYPRUS CREEK LAND COMPANY
                                    CYPRUS CREEK LAND RESOURCES, LLC
                                    EACC CAMPS, INC.
                                    EASTERN ASSOCIATED COAL CORP.
                                    EASTERN ROYALTY CORP.
                                    GALLO FINANCE COMPANY
                                    GOLD FIELDS CHILE, S.A.

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                                    GOLD FIELDS MINING CORPORATION
                                    GOLD FIELDS OPERATING CO. - ORTIZ
                                    GRAND EAGLE MINING, INC.
                                    HAYDEN GULCH TERMINAL, INC.
                                    HIGHLAND MINING COMPANY
                                    HILLSIDE MINING COMPANY
                                    INDEPENDENCE MATERIAL HANDLING
                                         COMPANY
                                    INTERIOR HOLDINGS CORP.
                                    JAMES RIVER COAL TERMINAL COMPANY
                                    JARRELL'S BRANCH COAL COMPANY
                                    JUNIPER COAL COMPANY
                                    KAYENTA MOBILE HOME PARK, INC.
                                    LOGAN FORK COAL COMPANY
                                    MARTINKA COAL COMPANY
                                    MIDCO SUPPLY AND EQUIPMENT
                                         CORPORATION
                                    MOUNTAIN VIEW COAL COMPANY
                                    MUSTANG ENERGY COMPANY, L.L.C.
                                    NORTH PAGE COAL CORP.
                                    OHIO COUNTY COAL COMPANY
                                    PATRIOT COAL COMPANY, L.P.
                                    PEABODY AMERICA, INC.
                                    PEABODY ARCHVEYOR, L.L.C.
                                    PEABODY COAL COMPANY
                                    PEABODY COALSALES COMPANY
                                    PEABODY COALTRADE, INC.
                                    PEABODY DEVELOPMENT COMPANY
                                    PEABODY DEVELOPMENT LAND HOLDINGS, LLC
                                    PEABODY ENERGY GENERATION HOLDING
                                    PEABODY ENERGY INVESTMENTS, INC.
                                    PEABODY ENERGY SOLUTIONS, INC.
                                    PEABODY HOLDING COMPANY, INC.
                                    PEABODY NATURAL GAS, LLC
                                    PEABODY NATURAL RESOURCES COMPANY
                                    PEABODY RECREATIONAL LANDS, L.L.C.
                                    PEABODY SOUTHWESTERN COAL COMPANY
                                    PEABODY TERMINALS, INC.
                                    PEABODY VENEZUELA COAL CORP.
                                    PEABODY-WATERSIDE DEVELOPMENT, L.L.C.
                                    PEABODY WESTERN COAL COMPANY
                                    PINE RIDGE COAL COMPANY
                                    POND CREEK LAND RESOURCES, LLC
                                    POND RIVER LAND COMPANY
                                    PORCUPINE PRODUCTION, LLC
                                    PORCUPINE TRANSPORTATION, LLC

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                                    POWDER RIVER COAL COMPANY
                                    PRAIRIE STATE GENERATING COMPANY, L.L.C.
                                    RIO ESCONDIDO COAL CORP.
                                    RIVERS EDGE MINING, INC.
                                    RIVERVIEW TERMINAL COMPANY
                                    SENECA COAL COMPANY
                                    SENTRY MINING COMPANY
                                    SNOWBERRY LAND COMPANY
                                    STAR LAKE ENERGY COMPANY, L.L.C.
                                    STERLING SMOKELESS COAL COMPANY
                                    THOROUGHBRED, L.L.C.
                                    THOROUGHBRED GENERATING COMPANY, LLC
                                    THOROUGHBRED MINING COMPANY, L.L.C.
                                    YANKEETOWN DOCK CORPORATION

                                    By:_________________________________________
                                       Name: Steven F. Schaab
                                       Title: Vice President

NEW GUARANTEEING SUBSIDIARIES:

                                    ARCLAR COMPANY, LLC

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    BLACK BEAUTY COAL COMPANY

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    BLACK BEAUTY EQUIPMENT COMPANY

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

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                                    BLACK BEAUTY HOLDING COMPANY, LLC

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    BLACK BEAUTY MINING, INC.

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    BLACK BEAUTY RESOURCES, INC.

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    BLACK BEAUTY UNDERGROUND, INC.

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    EAGLE COAL COMPANY

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    EMPIRE MARINE, LLC

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

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                                    FALCON COAL COMPANY

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    GIBCO MOTOR EXPRESS, LLC

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    HIGHWALL MINING SERVICES COMPANY

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

                                    SUGAR CAMP PROPERTIES

                                    By:_________________________________________
                                    Name: Steven F. Schaab
                                    Title: Vice President & Treasurer

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                                   SCHEDULE 1

                          NEW GUARANTEEING SUBSIDIARIES

1.       Arclar Company, LLC, an Indiana limited liability company

2.       Black Beauty Coal Company, an Indiana general partnership

3.       Black Beauty Equipment Company, an Indiana general partnership

4.       Black Beauty Holding Company, LLC, a Delaware limited liability company

5.       Black Beauty Mining, Inc., an Indiana corporation

6.       Black Beauty Resources, Inc., an Indiana corporation

7.       Black Beauty Underground, Inc., an Indiana corporation

8.       Eagle Coal Company, an Indiana general partnership

9.       Empire Marine, LLC, an Indiana limited liability company

10.      Falcon Coal Company, an Indiana general partnership

11.      Gibco Motor Express, LLC, an Indiana limited liability company

12.      Highwall Mining Services Company, a Delaware corporation

13.      Sugar Camp Properties, an Indiana general partnership

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