Document:

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                                                                   EXHIBIT 10.58

                          SECOND SUPPLEMENTAL INDENTURE

            Second Supplemental Indenture (this "SUPPLEMENTAL INDENTURE"), dated
as of April 22, 2004, among the entities listed on Schedule 1 attached hereto
(the "GUARANTEEING SUBSIDIARY"), 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");

            WHEREAS, the Indenture provides that under certain circumstances the
Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental
Indenture pursuant to which the Guaranteeing Subsidiary 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 Subsidiary 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 Subsidiary 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:

                  (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

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                        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 Subsidiary 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 First Supplemental Indenture for
                  the purposes of this Subsidiary Guarantee, notwithstanding any
                  stay, injunction or other

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                  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 Guaranteeing Subsidiary 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 Subsidiary 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 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

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                  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 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

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                  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
Subsidiary, as such, shall have any liability for any obligations of the Company
or any Guaranteeing Subsidiary 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 Subsidiary 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: ________________________________        By: _______________________________
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 VENEZUELA, LLC
                                         BTU WORLDWIDE, INC.
                                         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.
                                         EAGLE COAL COMPANY
                                         EASTERN ASSOCIATED COAL CORP.
                                         EASTERN ROYALTY CORP.
                                         EMPIRE MARINE, LLC
                                         FALCON COAL COMPANY
                                         GALLO FINANCE COMPANY
                                         GIBCO MOTOR EXPRESS, LLC
                                         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
                                         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
                                         PEABODY ENERGY INVESTMENTS, INC.
                                         PEABODY ENERGY SOLUTIONS, INC.
                                         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

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                                         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
                                         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.
                                         WILLIAMSVILLE COAL COMPANY, LLC
                                         YANKEETOWN DOCK CORPORATION

                                         By: __________________________________

                                              Name: Walter L. Hawkins, Jr.

                                              Title:  Vice President

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NEW GUARANTEEING SUBSIDIARIES:

                                         BTU EMPIRE CORPORATION

                                         By: __________________________________
                                         Name: Walter L. Hawkins, Jr.
                                         Title: Vice President & Treasurer

                                         BTU WESTERN RESOURCES, INC.

                                         By: __________________________________
                                         Name: Walter L. Hawkins, Jr.
                                         Title: Vice President & Treasurer

                                         COLORADO YAMPA COAL COMPANY

                                         By: __________________________________
                                         Name: Walter L. Hawkins, Jr.
                                         Title: Vice President & Treasurer

                                         SHOSHONE COAL CORPORATION

                                         By: __________________________________
                                         Name: Walter L. Hawkins, Jr.
                                         Title: Vice President & Treasurer

                                         TWENTYMILE COAL COMPANY

                                         By: __________________________________
                                         Name: Walter L. Hawkins, Jr.
                                         Title: Vice President & Treasurer

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                                   SCHEDULE 1

                          NEW GUARANTEEING SUBSIDIARIES

BTU EMPIRE CORPORATION, a Delaware corporation
BTU WESTERN RESOURCES, INC., a Delaware corporation
COLORADO YAMPA COAL COMPANY, a Delaware corporation
SHOSHONE COAL CORPORATION, a Delaware corporation
TWENTYMILE COAL COMPANY, a Delaware corporation

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                                                                   EXHIBIT 10.59

                               SECOND AMENDMENT TO
                           PEABODY ENERGY CORPORATION
                              EMPLOYMENT AGREEMENT
                              (FOR LISTED OFFICERS)

      THIS AMENDMENT (this "Amendment") is entered into as of the date set forth
on the signature page hereof, by and between Peabody Energy Corporation, a
Delaware corporation (the "Company") and Irl F. Engelhardt (the "Executive").

                                    RECITALS

      WHEREAS, the Company and Executive previously entered into that certain
Employment Agreement dated May 19, 1998 (the "Employment Agreement");

      WHEREAS, the Company deems it appropriate, for purposes of providing
Executive with adequate incentive to continue to serve in Executive's current
position with the Company, to provide Executive with added protection in the
event of certain corporate transactions;

      WHEREAS, pursuant to Section 10 of the Employment Agreement, the
Employment Agreement may be amended by written agreement of the parties thereto;

      NOW, THEREFORE, the parties hereto have agreed to amend the Employment
Agreement as follows:

                                       I.

      Section 6(1)(d)(i) of the Employment Agreement is hereby amended by
deleting the words "; provided, however, that such Gross-Up Payment shall not
exceed $3,501,627" at the end thereof.

                                       II.

      In all other respects, the Employment Agreement shall remain in full force
and effect.

      IN WITNESS WHEREOF, this Amendment has been executed and delivered by the
parties hereto.

                                         PEABODY ENERGY CORPORATION

                                         By: /s/ Robert B. Karn III
                                             _______________________________
                                             Robert B. Karn III
                                             Compensation Committee Chairperson

                                         /s/ Irl F. Engelhardt
                                         ___________________________________
                                         Irl F. Engelhardt

                                         June 15, 2004

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