AMENDMENT NO. 1 TO EDISON MISSION HOLDINGS CO. AND SUBSIDIARIES "HOMER CITY" TAX ALLOCATION AGREEMENT

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Exhibit 10.1

AMENDMENT NO. 1 TO
EDISON MISSION HOLDINGS CO. AND SUBSIDIARIES
"HOMER CITY"
TAX ALLOCATION AGREEMENT

        This AMENDMENT NO. 1 (this " Amendment ") is made and entered into effective as of March 31, 2006, by and among Edison Mission Holdings Co., a Delaware corporation (" EMHC "), Mission Energy Westside, Inc., a Delaware corporation (" MEW "), Chestnut Ridge Energy Company, a Delaware corporation (" Chestnut Ridge "), Edison Mission Finance Co., a Delaware corporation (" FinanceCo "), Homer City Property Holdings, Inc., a Delaware corporation (" PropertyCo "), and EME Homer City Generation L.P., a Pennsylvania limited partnership (" EME Homer City ") (collectively, EMHC, MEW, Chestnut Ridge, FinanceCo, PropertyCo and EME Homer City are referred to as the " Homer City Subgroup ", and individually referred to as " Subgroup Members ").

        WHEREAS, the Subgroup Members entered into that certain Tax Allocation Agreement dated as of January 1, 2002 (the " Tax Allocation Agreement ") addressing the computation of all tax liabilities due and owing among the Subgroup Members with regard to taxable periods beginning on or after January 1, 2002, as well as for computations for prior taxable periods.

        WHEREAS, the Subgroup Members desire to amend the Tax Allocation Agreement upon and subject to the terms and conditions hereinafter set forth.

        NOW THEREFORE, in consideration of the premises and the agreements contained herein, the Parties agree as follows:

        1.      Amendments to the Tax Allocation Agreement . Section 2 of the Tax Allocation Agreement is hereby amended and restated in its entirety as follows:

        "a.    In General . For each taxable period for which this Agreement is applicable, federal income tax or state combined or consolidated income tax liabilities will be allocated at least quarterly in the manner outlined in Section 1 above. Payments of federal or state tax liabilities by each Subgroup Member shall be made of its allocated portion of the Homer City Subgroup tax liability as computed under Section 1 above, net of any Separate Benefits computed under Section 2b. below for such Subgroup, either by legal offset of intercompany accounts or by payment in cash upon demand by EMHC, at the dates payment is due under that certain Edison Mission Energy and Subsidiaries Tax Allocation Agreement, dated as of even date herewith (the " EME and Subsidiaries Tax Allocation Agreement "), provided that such payments are consistent with and are not limited by debt financing restrictions and covenants and, provided, further, with respect to EME Homer City, to the extent legal offset of intercompany accounts is not available and in lieu of payment in cash upon demand by EMHC, so long as the Loan Conditions (as defined below) are satisfied, EME Homer City may satisfy the amount of its allocated portion of the Homer City Subgroup tax liability by requesting that, and EME Homer City hereby requests that until written notice is provided by EME Homer City to the other parties hereto otherwise, such amount be deemed a loan under t