Exhibit 4.8

EXECUTION COPY

ASSUMPTION AND RELEASE AGREEMENT

ASSUMPTION AND RELEASE AGREEMENT, dated as of December 7, 2001 (this "Agreement"), made by Edison Mission Holdings Co., a California corporation
("Holdings"), Edison Mission Finance Co., a California corporation ("FinanceCo"), The Bank of New York, as successor in interest to United States Trust Company of New York, as Bondholder Trustee under
the Indenture (as defined below), The Bank of New York, as successor in interest to United States Trust Company of New York, as Collateral Agent under the Guarantee and Collateral Agreement (as
defined below) and EME Homer City Generation L.P., a Pennsylvania limited partnership ("EME Homer City").

RECITALS

WHEREAS, Edison Mission Holdings Co. ("Holdings") entered into the Indenture, dated as of May 27, 1999, between Holdings and the Bondholder Trustee (as
amended from time to time, the "Indenture") pursuant to which Holdings issued $300,000,000 principal amount of 8.137% Senior Secured Bonds due 2019 and $530,000,000 principal amount of 8.734% Senior
Secured Bonds due 2026 which it subsequently exchanged for a like amount of substantially similar bonds that had been registered under the Securities Act of 1933 (collectively, the "Bonds").

WHEREAS,
the direct and indirect subsidiaries of Holdings, including EME Homer City (collectively, the "Subsidiary Guarantors") entered into the Guarantee and Collateral Agreement, dated
as of March 18, 1999, among Holdings, each Subsidiary Guarantor and the Collateral Agent (as amended from time to time, the "Guarantee and Collateral Agreement") pursuant to which each
Subsidiary Guarantor unconditionally guaranteed the obligations of Holdings under the Indenture and the Bonds.

WHEREAS,
Holdings and FinanceCo entered into the Subordinated Loan Agreement, dated as of March 18, 1999 (the "Holdings Loan Facility"), pursuant to which Holdings loaned the
proceeds of the issuance of the Bonds to FinanceCo.

WHEREAS,
FinanceCo and EME Homer City entered into the Subordinated Loan Agreement, dated as of March 18, 1999 (the "FinanceCo Loan Facility"), pursuant to which FinanceCo loaned
the proceeds of the loan under the Holdings Loan Facility to EME Homer City.

WHEREAS,
EME Homer City used the proceeds of the loan under the FinanceCo Loan Facility to purchase (the "Purchase") certain coal-fired power generation and related assets
(the "Facilities").

WHEREAS,
pursuant to its Consent Solicitation Statement, dated November 21, 2001, as may be amended and supplemented prior to the expiration date of the Consent Solicitation
described therein (the "Consent Solicitation Statement"), Holdings is soliciting consents of the holders of the Bonds to certain Proposals (as defined in the Consent Solicitation Statement), including
the release of each Subsidiary Guarantor from its respective obligations under the Guarantee and Collateral Agreement and the amendment of and waiver to certain provisions of the Indenture, in order
to effectuate a sale-leaseback transaction of the Facilities (the "Sale-Leaseback").

WHEREAS,
the requisite number of consents to the Proposals has been received by the Bondholder Trustee in the Consent Solicitation.

WHEREAS,
FinanceCo desires to expressly assume all obligations of Holdings under the Indenture and the Bonds, and Holdings desires to be released from all obligations under the Indenture
and the Bonds.

WHEREAS,
EME Homer City desires to expressly assume all obligations of FinanceCo under the Indenture and the Bonds, and FinanceCo desires to be released from all obligations under the
Indenture and the Bonds.

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NOW
THEREFORE, for and in consideration of the mutual promises and covenants set forth herein:







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IN
WITNESS WHEREOF, this Agreement has been duly executed and delivered as of the date first written above.

| |  | EME HOMER CITY GENERATION L.P.             
| |  | -------------------------------------------
| |  | By:                                        
| |  | By:                                        
| |  |                                            
| |  |                                            
| |  | EDISON MISSION HOLDINGS CO.                
| |  | By:                                        
| |  |                                            
| |  |                                            
| |  | EDISON MISSION FINANCE CO.                 
| |  | By:                                        
| |  |                                            
| |  |                                            
| |  | THE BANK OF NEW YORK,
As Bondholder Trustee
| |  | By:                                        
| |  |                                            
| |  |                                            
| |  | THE BANK OF NEW YORK,
As Collateral Agent  
| |  | By:                                        
| |  |                                            
| |  |                                            

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