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                                                                    EXHIBIT 4.13

                          THIRD SUPPLEMENTAL INDENTURE

                  Third Supplemental Indenture (this "SUPPLEMENTAL INDENTURE"),
dated as of October 18, 2004, among the entities listed on Schedule 1 attached
hereto ("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 U.S. Bank National Association, as Trustee
under the Indenture referred to below (the "TRUSTEE").

                               W I T N E S S E T H

                  WHEREAS, the Company has heretofore executed and delivered to
the Trustee the First Supplemental Indenture dated as of March 23, 2004 to the
Indenture dated as of March 19, 2004, (the "BASE INDENTURE," and, together with
the First Supplemental Indenture, the "INDENTURE") providing for the issuance of
an unlimited amount of 5-7/8% Senior Notes due 2016 (the "NOTES"); as
supplemented by the Second Supplemental Indenture, dated as of April 22, 2004;

                  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
and the Indenture on the terms and conditions set forth herein (the "SUBSIDIARY
GUARANTEE"); and

                  WHEREAS, pursuant to Section 9.01 of the Base 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 agrees 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:


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                        (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 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.

                  (b)   The obligations hereunder 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 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.

                  (f)   The Guaranteeing Subsidiaries shall not be entitled to
                        any right of subrogation in relation to the Holders in
                        respect of any obligations

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                        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 First
                        Supplemental 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 First Supplemental 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 9.04 of the First Supplemental
                        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 9 of the First
                        Supplemental Indenture shall result in the obligations
                        of such Subsidiary Guarantor under its 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 Subsidiary
                        Guarantor is the surviving Person) another corporation,
                        Person or entity whether or not affiliated with such
                        Subsidiary Guarantor unless:

                        (i)   subject to Section 9.04 of the First Supplemental
                              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

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                              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 First
                        Supplemental 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 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

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                        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 First Supplemental 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 9 of the First Supplemental 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 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.

                  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.

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                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed and attested, all as of the date
first above written.

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

By: /s/ WALTER L. HAWKINS, JR.             By: /s/ PHILIP G. KANE, JR.
    ---------------------------------          ---------------------------------
Name: Walter L. Hawkins, Jr.               Name: Philip G. Kane, Jr.

Title: Vice President and Treasurer        Title: Vice President

EXISTING SUBSIDIARY GUARANTORS:

                                           AFFINITY MINING COMPANY
                                           ARCLAR COMPANY, LLC
                                           ARID OPERATIONS INC.
                                           BEAVER DAM COAL COMPANY
                                           BIG RIDGE, INC.
                                           BIG SKY COAL COMPANY
                                           BLACK BEAUTY COAL COMPANY
                                           BLACK BEAUTY EQUIPMENT COMPANY
                                           BLACK BEAUTY HOLDING COMPANY, LLC
                                           BLACK BEAUTY MINING, INC.
                                           BLACK BEAUTY RESOURCES, INC.
                                           BLACK BEAUTY UNDERGROUND, INC.
                                           BLACK HILLS MINING COMPANY, LLC
                                           BLACK STALLION COAL COMPANY, LLC
                                           BLACK WALNUT COAL COMPANY
                                           BLUEGRASS COAL COMPANY
                                           BTU EMPIRE CORPORATION
                                           BTU VENEZUELA, LLC
                                           BTU WORLDWIDE, INC.
                                           CABALLO COAL COMPANY
                                           CHARLES COAL COMPANY
                                           CLEATON COAL COMPANY
                                           COAL PROPERTIES CORP.
                                           COLONY BAY COAL COMPANY
                                           COLORADO YAMPA COAL COMPANY
                                           COOK MOUNTAIN COAL COMPANY
                                           COTTONWOOD LAND COMPANY
                                           CYPRUS CREEK LAND COMPANY
                                           CYPRUS CREEK LAND RESOURCES, LLC
                                           EACC CAMPS, INC.
                                           EAGLE COAL COMPANY
                                           EASTERN ASSOCIATED COAL CORP.

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                                           EASTERN ROYALTY CORP.
                                           EMPIRE MARINE, LLC
                                           FALCON COAL COMPANY
                                           GALLO FINANCE COMPANY
                                           GIBCO MOTOR EXPRESS, LLC
                                           GOLD FIELDS CHILE, S.A.
                                           GOLD FIELDS MINING CORPORATION
                                           GOLD FIELDS OPERATING CO. - ORTIZ
                                           GRAND EAGLE MINING, INC.
                                           HAYDEN GULCH TERMINAL, INC.
                                           HIGHLAND MINING COMPANY
                                           HIGHWALL MINING SERVICES COMPANY
                                           HILLSIDE MINING COMPANY
                                           INDEPENDENCE MATERIAL HANDLING
                                              COMPANY
                                           INDIAN HILL COMPANY
                                           INTERIOR HOLDINGS CORP.
                                           JAMES RIVER COAL TERMINAL COMPANY
                                           JARRELL'S BRANCH COAL COMPANY
                                           JUNIPER COAL COMPANY
                                           KANAWHA RIVER VENTURES I, LLC
                                           KAYENTA MOBILE HOME PARK, INC.
                                           LOGAN FORK COAL COMPANY
                                           MARTINKA COAL COMPANY
                                           MIDCO SUPPLY AND EQUIPMENT
                                              CORPORATION
                                           MIDWEST COAL ACQUISITION CORP.
                                           MOUNTAIN VIEW COAL COMPANY
                                           MUSTANG ENERGY COMPANY, L.L.C.
                                           NORTH PAGE COAL CORP.
                                           OHIO COUNTY COAL COMPANY
                                           PATRIOT COAL COMPANY, L.P.
                                           PDC PARTNERSHIP HOLDINGS, INC.
                                           PEABODY AMERICA, INC.
                                           PEABODY ARCHVEYOR, L.L.C.
                                           PEABODY COAL COMPANY
                                           PEABODY COALSALES COMPANY
                                           PEABODY COALTRADE, INC.
                                           PEABODY DEVELOPMENT COMPANY,LLC
                                           PEABODY DEVELOPMENT LAND HOLDINGS,
                                           LLC
                                           PEABODY ENERGY GENERATION HOLDING
                                           COMPANY
                                           PEABODY ENERGY INVESTMENTS, INC.
                                           PEABODY ENERGY SOLUTIONS, INC

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                                           PEABODY HOLDING COMPANY, INC.
                                           PEABODY NATURAL GAS, LLC
                                           PEABODY NATURAL RESOURCES COMPANY
                                           PEABODY POWERTREE INVESTMENTS, LLC
                                           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
                                           PEC EQUIPMENT COMPANY, LLC
                                           PINE RIDGE COAL COMPANY
                                           POINT PLEASANT DOCK COMPANY, LLC
                                           POND CREEK LAND RESOURCES, LLC
                                           POND RIVER LAND COMPANY
                                           PORCUPINE PRODUCTION, LLC
                                           PORCUPINE TRANSPORTATION, LLC
                                           POWDER RIVER COAL COMPANY
                                           PRAIRIE STATE GENERATING COMPANY, LLC
                                           RIO ESCONDIDO COAL CORP.
                                           RIVERS EDGE MINING, INC.
                                           RIVERVIEW TERMINAL COMPANY
                                           SENECA COAL COMPANY
                                           SENTRY MINING COMPANY
                                           SHOSHONE COAL CORPORATION
                                           SNOWBERRY LAND COMPANY
                                           STAR LAKE ENERGY COMPANY, L.L.C.
                                           STERLING SMOKELESS COAL COMPANY
                                           SUGAR CAMP PROPERTIES
                                           THOROUGHBRED, L.L.C.
                                           THOROUGHBRED GENERATING COMPANY, LLC
                                           THOROUGHBRED MINING COMPANY, L.L.C.
                                           TWENTYMILE COAL COMPANY
                                           WILLIAMSVILLE COAL COMPANY, LLC
                                           YANKEETOWN DOCK CORPORATION

                                           By: /s/ WALTER L. HAWKINS, JR.
                                               --------------------------------

                                               Name: Walter L. Hawkins, Jr.

                                               Title: Vice President

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NEW GUARANTEEING SUBSIDIARIES:

                                           APPALACHIA MINE SERVICES, LLC

                                           By: /s/ WALTER L. HAWKINS, JR.
                                               ---------------------------------
                                           Name: Walter L. Hawkins, Jr.
                                           Title: Vice President & Treasurer

                                           COAL RESERVES HOLDING LIMITED
                                           LIABILITY COMPANY NO. 1.

                                           By: /s/ WALTER L. HAWKINS, JR.
                                               ---------------------------------
                                           Name: Walter L. Hawkins, Jr.
                                           Title: Vice President & Treasurer

                                           COAL RESERVES HOLDING LIMITED
                                           LIABILITY COMPANY NO. 2.

                                           By: /s/ WALTER L. HAWKINS, JR.
                                               ---------------------------------
                                           Name: Walter L. Hawkins, Jr.
                                           Title: Vice President & Treasurer

                                           COALSALES, LLC

                                           By: /s/ WALTER L. HAWKINS, JR.
                                               ---------------------------------
                                           Name: Walter L. Hawkins, Jr.
                                           Title: Vice President & Treasurer

                                           PEABODY COALTRADE INTERNATIONAL, LLC

                                           By: /s/ WALTER L. HAWKINS, JR.
                                              ----------------------------------
                                           Name: Walter L. Hawkins, Jr.
                                           Title: Vice President & Treasurer

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                                   SCHEDULE 1

                          NEW GUARANTEEING SUBSIDIARIES

APPALACHIA MINE SERVICES, LLC, a Delaware Limited Liability Company
COAL RESERVES HOLDING LIMITED LIABILITY COMPANY NO. 1, a Delaware Limited
Liability Company
COAL RESERVES HOLDING LIMITED LIABILITY COMPANY NO. 2, a Delaware Limited
Liability Company
COALSALES, LLC, a Delaware Limited Liability Company
PEABODY COALTRADE INTERNATIONAL, LLC, a Delaware Limited Liability Company

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