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                                                                   EXHIBIT 10.70

               SECOND AMENDMENT TO RECEIVABLES PURCHASE AGREEMENT

            THIS SECOND AMENDMENT TO RECEIVABLES PURCHASE AGREEMENT (the
"Amendment") dated as of February 18, 2004, is made by and among P & L
Receivables Company, LLC, as seller (the "Seller"), Peabody Energy Corporation,
as initial Servicer (the "Servicer"), Big Sky Coal Company, Caballo Coal
Company, Eastern Associated Coal Corp., Peabody Coal Sales Company, Peabody Coal
Company, Peabody Western Coal Company, Powder River Coal Company, Peabody
Holding Company, Inc., Peabody Coaltrade, Inc., as Sub-Servicers, Market Street
Funding Corporation, as Issuer (the "Issuer"), and PNC BANK, NATIONAL
ASSOCIATION, as administrator (the "Administrator").

                                   WITNESSETH:

            WHEREAS, the parties hereto are parties to that certain Receivables
Purchase Agreement dated as of February 20, 2002, by and among the Seller, the
Servicer, the Sub-Servicers, the Issuer, and the Administrator, as amended by
that certain First Amendment to Liquidity Asset Purchase Agreement dated as of
February 27, 2003 (the "Receivables Purchase Agreement"), and desire to amend
the terms thereof as set forth herein.

            NOW, THEREFORE, the parties hereto, in consideration of their mutual
covenants and agreements hereinafter set forth and intending to be legally bound
hereby, covenant and agree as follows:

1.    Definitions.

            Defined terms used herein unless otherwise defined herein shall have
the meanings ascribed to them in the Receivables Purchase Agreement as amended
by this Amendment.

2.    Amendments to Receivables Purchase Agreement.

            (a)   Exhibit I, Definition of "Defaulted Receivable". The
definition of "Defaulted Receivable" set forth in Exhibit I of the Receivables
Purchase Agreement is hereby amended and restated as follows:

                  "Defaulted Receivable" means a Receivable:

                  (a) as to which any payment, or part thereof, remains unpaid
            for more than 60 days from the due date for such payment (which
            shall be determined without regard to any credit memos or credit
            balances available to the obligor), or

                  (b) without duplication (i) as to which an Insolvency
            Proceeding shall have occurred with respect to the Obligor thereof
            or any other Person obligated thereon or owning any Related Security
            with respect thereto, or (ii) that has been written off the Seller's
            books as uncollectible.

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            (b)   Exhibit I, Definition of "Eligible Receivable". The definition
of "Eligible Receivable" set forth in Exhibit I of the Receivables Purchase
Agreement is hereby amended and restated as follows:

                  (i)   Clause (a) of the definition of "Eligible Receivable" is
hereby amended and restated to read as follows:

                        "(a) the Obligor of which is (i) a United States
            resident or if such Obligor is not a United States resident: (A)
            such Pool Receivable must result from goods sold and shipped from
            the Originator in the United States and payment for such goods must
            be denominated and payable only in Dollars and payable to an
            Originator at a Lock-Box Account, (B) if such Obligor is a resident
            of Canada, the total of all Eligible Receivables the Obligors of
            which are Canadian residents does not exceed 3% (or, if at any time
            the foreign currency rating of Canada falls below A by Standard &
            Poor's or A2 by Moody's, 2%) of all Eligible Receivables and, and
            (C) are if such Obligor is neither a U.S. nor a Canadian resident,
            the total of all Eligible Receivables the Obligors of which are both
            non-U.S. and non-Canadian residents does not exceed 5% of all
            Eligible Receivables, (ii) not a government or a governmental
            subdivision, affiliate or agency, except that up to 3% of all
            Eligible Receivables may consist of Receivables the Obligors of
            which are governments, governmental subdivisions, affiliates or
            agencies, provided, however, that TVA shall not be subject to the
            restrictions of this subsection (ii), (iii) not subject to any
            action of the type described in paragraph (f) of Exhibit V to the
            Agreement, (iv) not an Affiliate of Peabody or any other Originator,
            and (v) not an Obligor as to which the Administrator, in its
            reasonable business judgment, has notified the Seller that such
            Obligor is not acceptable."

                  (ii) A new clause (q) is hereby added to the definition of
"Eligible Receivable, to follow immediately after existing clause (p) and to
read as set forth below, and the period at the end of clause (p) is deleted and
the following words are inserted in lieu thereof: ", and":

                        "(q) that is not a Receivable considered to be a
            "quality accrual" (as reported on the monthly Information Package),
            except that up to 5% of Eligible Receivables may be "quality
            accruals".

3.    Representations and Warranties. Each of the Seller, the Servicer, and the
      Sub-Servicers hereby represents and warrants to the Issuer and
      Administrator as follows:

            A. The representations and warranties of the Seller, the Servicer,
and the Sub-Servicers contained in the Receivables Purchase Agreement are true
and correct on and as of the date hereof with the same force and effect as
though made by the Seller, the Servicer, and the

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Sub-Servicers on such date, except to the extent that any such representation or
warranty expressly relates solely to a previous date; and

            B. Each of the Seller, the Servicer, and the Sub-Servicers is in
compliance with all terms, conditions, provisions, and covenants contained in
the Receivables Purchase Agreement and the execution, delivery, and performance
of this Amendment have been duly authorized by all necessary corporate action,
require no governmental approval, and will neither contravene, conflict with,
nor result in the breach of any law, charter, articles, or certificate of
incorporation, bylaws, or agreement governing or binding upon any of the Seller,
the Servicer, and the Sub-Servicers or any of their property; and, no Unmatured
Termination Event or Termination Event has occurred and is continuing or would
result from the making of this Amendment.

4.    Conditions of Effectiveness of this Amendment. The effectiveness of this
      Amendment is expressly conditioned upon satisfaction of each of the
      following conditions precedent:

      A.    Legal Details; Counterparts. All legal details and proceedings in
connection with the transactions contemplated by this Amendment shall be in form
and substance satisfactory to the Administrator, and the Administrator shall
have received from the Seller, the Issuer, the Servicer and the Sub-Servicers
all such other counterpart originals or certified or other copies of such
documents and proceedings in connection with such transactions, in form and
substance satisfactory to the Administrator.

      B.    No Default. As of the date hereof, no Unmatured Termination Event or
Termination Event has occurred and is continuing and each of the Seller, the
Servicer, and the Sub-Servicers by executing this Amendment confirms the same
and also confirms the accuracy of the representations and warranties in Section
3 above.

5.    Amendment. The Receivables Purchase Agreement referred to herein and
certain of the exhibits and schedules thereto are hereby amended in accordance
with the terms hereof and any reference to the Receivables Purchase Agreement in
any document, instrument, or agreement shall hereafter mean and include the
Receivables Purchase Agreement, including such schedules and exhibits, as
amended hereby.

6.    Force and Effect. Each of the Seller, the Servicer, and the Sub-Servicers
reconfirms, restates, and ratifies the Receivables Purchase Agreement, the
Transaction Documents and all other documents executed in connection therewith
except to the extent any such documents are expressly modified by this Amendment
and each of the Seller, the Servicer, and the Sub-Servicers confirms that all
such documents have remained in full force and effect since the date of their
execution.

7.    No Waiver. Except as expressly provided herein, this Amendment does not
and shall not be deemed to constitute a waiver by Issuer of any Termination
Event under the Receivables Purchase

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Agreement, or of any event which with the passage of time or the giving of
notice or both would constitute a Termination Event.

9.    Governing Law. This Amendment shall be deemed to be a contract under the
laws of the State of Illinois and for all purposes shall be governed by and
construed and enforced in accordance with the internal laws of the State of
Illinois without regard to its conflict of laws principles.

10.   Counterparts. This Amendment may be signed in any number of counterparts
each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument.

11.   Effective Date. This Amendment shall be effective as of and shall be dated
as of the date of satisfaction of all conditions set forth in Section 4 of this
Amendment.

                         [SIGNATURES BEGIN ON NEXT PAGE]

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                  [SIGNATURE PAGE 1 OF 6 TO SECOND AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT]

      IN WITNESS WHEREOF and intending to be legally bound hereby, the parties
hereto have executed this Amendment as of the date first above written.

                              P & L RECEIVABLES COMPANY, LLC
                              as Seller

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

                              PEABODY ENERGY CORPORATION,
                              as initial Servicer

                              By: /s/ L. Brent Stottlemyre
                                  ----------------------------------------------
                                  Name: L. Brent Stottlemyre
                                  Title: Vice President - Finance and Controller

<PAGE>

                  [SIGNATURE PAGE 2 OF 6 TO SECOND AMENDMENT TO
                        RECEIVABLES PURCHASE AGREEMENT]

                              BIG SKY COAL COMPANY,
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

                              CABALLO COAL COMPANY,
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

                              EASTERN ASSOCIATED COAL CORP.,
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

                              PEABODY COAL SALES COMPANY,
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

<PAGE>

                  [SIGNATURE PAGE 3 OF 6 TO SECOND AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT]

                              PEABODY COAL COMPANY,
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

                              PEABODY WESTERN COAL COMPANY,
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

                              POWDER RIVER COAL COMPANY,
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

                              PEABODY HOLDING COMPANY, INC.
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

<PAGE>

                  [SIGNATURE PAGE 4 OF 6 TO SECOND AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT]

                              PEABODY COALTRADE, INC.
                              as Sub-Servicer

                              By: /s/ Walter L. Hawkins, Jr.
                                  ----------------------------------------------
                                  Name: Walter L. Hawkins, Jr.
                                  Title: Vice President and Treasurer

<PAGE>

                  [SIGNATURE PAGE 5 OF 6 TO SECOND AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT]

                              MARKET STREET FUNDING CORPORATION,
                              as Issuer

                              By: /s/ Evelyn Echevarria
                                  ----------------------------------------------
                                  Name: Evelyn Echevarria
                                  Title: Vice President

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                  [SIGNATURE PAGE 6 OF 6 TO SECOND AMENDMENT TO
                         RECEIVABLES PURCHASE AGREEMENT]

                              PNC BANK, NATIONAL ASSOCIATION,
                              as Administrator

                              By: /s/ John Smathers

                                  Name: John Smathers
                                  Title: Vice President

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