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Exhibit 10.23.1

Execution Copy

AMENDED AND RESTATED INTERCOMPANY LOAN SUBORDINATION AGREEMENT

        AMENDED AND RESTATED INTERCOMPANY LOAN SUBORDINATION AGREEMENT (this
"Agreement"), dated as of December 7, 2001, among (i) EDISON MISSION HOLDINGS
CO., a California corporation ("EME Holdings"), (ii) EDISON MISSION FINANCE CO.,
a California corporation ("Edison Mission Finance"), (iii) HOMER CITY PROPERTY
HOLDINGS, INC., a California corporation ("Homer City Holdings"), (iv) CHESTNUT
RIDGE ENERGY CO., a California corporation ("Chestnut Ridge"), (v) MISSION
ENERGY WESTSIDE, INC., a California corporation ("MEW"), (vi) EME HOMER CITY
GENERATION L.P., a Pennsylvania limited partnership ("Homer City" or the
"Facility Lessee" and, together with EME Holdings, Edison Mission Finance, Homer
City Holdings, Chestnut Ridge and MEW, the "Loan Parties"), and (vii) THE BANK
OF NEW YORK, as successor to UNITED STATES TRUST COMPANY OF NEW YORK, as
collateral agent for the holders of the Initial Lessor Notes (as such term is
defined in the Participation Agreement) (in such capacity, the "Collateral
Agent").

RECITALS

        WHEREAS, contemporaneously herewith Homer City, a wholly owned
subsidiary of Edison Mission Midwest Holdings Co. ("Holdings"), will enter into
a transaction pursuant to the eight Participation Agreements, in each case, by
and among Homer City, the Owner Lessor (as defined therein), Wells Fargo Bank
Northwest, National Association, not in its individual capacity but solely as
Owner Manager, the Owner Participant (as defined therein), Homer City Funding
LLC, as Lender and the Collateral Agent, as Indenture Trustee, Bondholder
Trustee and Security Agent (as amended, modified and supplemented and in effect
from time to time, each a "Participation Agreement") whereby Homer City shall
sell certain of its generating assets to the Owner Lessors and the Owner Lessors
shall lease such generating assets to Homer City under each Facility Lease;

        WHEREAS, the holders of the Initial Lessor Notes (as such term is
defined in the Participation Agreement) have purchased the Initial Lessor Notes
from the Owner Lessor and have been granted a security interest in the Facility
Lease as collateral for the Initial Lessor Notes;

        WHEREAS, Edison Mission Finance has entered into a Subordinated Loan
Agreement, dated as of March 18, 1999 (the "Holdings Loan Agreement"), with EME
Holdings, pursuant to which EME Holdings has agreed to make loans ("Holdings
Loans") to Edison Mission Finance from time to time with the proceeds of the
Holdings Loans on the terms and subject to the conditions contained in the
Holdings Loan Agreement.

        WHEREAS, EME Homer City has entered into the Subordinated Loan
Agreement, dated as of March 18, 1999 (the "Finance Loan Agreement"), with
Edison Mission Finance, pursuant to which Edison Mission Finance has agreed to
make loans ("Finance Loans") to EME Homer City from time to time with the
proceeds of the Holdings Loans on the terms and subject to the conditions
contained in the Finance Loan Agreement.

        WHEREAS, EME Homer City has entered into the Subordinated Revolving Loan
Agreement, dated as of March 18, 1999 (the "Revolving Loan Agreement"), with
Edison Mission Finance, pursuant to which Edison Mission Finance has agreed to
make loans ("Revolving Loans") to EME Homer City from time to time on the terms
and subject to the conditions contained in the Revolving Loan Agreement.

        WHEREAS, in connection with the transactions contemplated by the
Participation Agreements, the parties hereto will agree to subordinate certain
claims against Homer City under the Holdings

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Loans, Finance Loans and Revolving Loans to the rights of holders of the
Obligations (as defined herein); and

        WHEREAS, the execution and delivery of this Agreement is a condition
precedent to each of the Participation Agreements.

        NOW, THEREFORE, in consideration of the foregoing premises and for other
good and valuable consideration, the receipt of which is hereby acknowledged,
each of the parties hereto hereby agrees to amend and restate the Intercompany
Loan Subordination Agreement between the Loan Parties and the Collateral Agent,
dated as of March 18, 1999 (the "Intercompany Loan Subordination Agreement") in
its entirety as follows:

ARTICLE I
DEFINITIONS; PRINCIPLES OF CONSTRUCTION

        Section 1.1    Definitions.    (a) Unless otherwise expressly provided
herein, capitalized terms used but not defined in this Agreement, including in
the Preamble and the Recitals, shall have the meanings given to such terms in
each Participation Agreement.

        (b)    Other Defined Terms.    The following terms, when used herein,
shall have the following meanings:

        "Intercompany Borrower" shall mean any Loan Party in its capacity as
borrower under any Intercompany Loan Agreement.

        "Intercompany Loans" shall mean any indebtedness by any Loan Party
relating to an Intercompany Loan Agreement.

        "Intercompany Loan Agreement" shall mean the Holdings Loan Agreement,
the Finance Loan Agreement, the Revolving Loan Agreement and any other loan
agreement to be entered into from time to time by an Intercompany Borrower and a
Subordinated Party.

        "Obligations" shall mean (i) all obligations of Homer City owed now or
hereafter under each of the Participation Agreements, and related Operative
Documents, including without limitation Basic Lease Rent, Termination Value, any
Supplemental Rent (whether for indemnities, costs, expenses or otherwise) now or
hereafter owed by Homer City to the Owner Lessor, the Security Agent, the Lease
Indenture Trustee, the Lender or the Bondholder Trustee under the Operative
Documents and (ii) obligations owed now or hereafter by Homer City with respect
to or on account of Permitted Indebtedness.

        "Proceeding" shall have the meaning given to such term in Section 3.2.

        "Secured Party" shall mean any party to whom Homer City owes an
Obligation.

        "Senior Claims" shall have the meaning given to such term in
Section 2.1(a).

        "Subordinated Claims" shall have the meaning given to such term in
Section 2.1(a).

        "Subordinated Notes" shall have the meaning given to such term in
Section 2.1(c).

        "Subordinated Party" shall mean any Loan Party in its capacity as lender
under an Intercompany Loan Agreement.

        Section 1.2    Principles of Construction.    Unless otherwise expressly
provided herein, the principles of construction set forth in the Participation
Agreement shall apply to this Agreement.

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ARTICLE II
SUBORDINATION PROVISIONS

        Section 2.1    Subordination of Intercompany Loans.    Until all
Obligations shall have been indefeasibly paid in full and the Facility Lease,
the other Operative Documents and any agreement relating to Permitted
Indebtedness have terminated in accordance with their terms:

        (a)  (i) all principal of, premium, if any, interest and any other
amounts owing on any Intercompany Loan made by any Loan Party, whether direct or
indirect, absolute or contingent, due or to become due, or now existing or
hereafter incurred or created ("Subordinated Claims") shall be subordinate to
the prior payment of and junior in right of payment to all principal of,
premium, if any, and interest (including default interest and interest accruing
after the initiation of any Proceeding whether or not allowed as a claim in such
a Proceeding) owing in respect of all other Obligations owed by Homer City under
the Operative Documents and under any Permitted Indebtedness (collectively,
"Senior Claims")

        (b)  no Loan Party shall, directly or indirectly, make any payment of
principal or interest on account of, or transfer any collateral for any part of,
any Subordinated Claims; provided, however, that the Loan Parties may make
regularly scheduled payments of interest and principal on account of
Subordinated Claims so long as at such time Restricted Payments are permitted to
be made pursuant to the terms of the Amended and Restated Security Deposit
Agreement;

        (c)  the Subordinated Parties shall not demand, sue for or accept any
payment or collateral in respect of any Subordinated Claims, or take any other
action to enforce their rights or exercise any remedies in respect of any
Subordinated Claims (whether upon the occurrence or during the continuation of
an event of default under the related Intercompany Loan Agreement or an event of
default under any promissory notes evidencing Subordinated Claims (collectively,
"Subordinated Notes" or otherwise), or cancel, set off or otherwise discharge
any part of any Subordinated Claims; and

        (d)  no Intercompany Borrower or Subordinated Party shall otherwise take
any action prejudicial to or inconsistent with the priority position of the
Secured Parties over the Subordinated Parties created by this Section 2.1.

        Section 2.2    Reliance.    All Senior Claims shall conclusively be
deemed to have been created, contracted or incurred in reliance on the
subordination provisions contained in this Agreement and all dealings between
the Loan Parties and each of the holders of Senior Claims shall be deemed to
have been consummated in reliance upon the subordination provisions contained
herein.

        Section 2.3    Other Holders.    The subordination provisions set forth
in this Agreement shall be binding upon transferees or assignees of the
Subordinated Parties and upon each other holder of Subordinated Claims and shall
inure to the benefit of transferees or assignees of the holders of the Initial
Lessor Notes and every other holder of Senior Claims.

ARTICLE III
WRONGFUL COLLECTIONS

        Section 3.1    Turnover.    Should any payment on account of, or any
collateral for any part of, any Subordinated Claims be received by the
Subordinated Parties in violation of this Agreement, such payment or collateral
shall be delivered forthwith to the Collateral Agent for application in
accordance with the Amended and Restated Security Deposit Agreement and the
other Security Documents. The Collateral Agent is irrevocably authorized to
supply any required endorsement or assignment which may have been omitted. Until
so delivered, any such payment or collateral shall be held by the Subordinated
Parties in trust for the Secured Parties and shall not be commingled with other
funds or property of the Subordinated Parties.

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        Section 3.2    Survival of Obligation.    The obligation of the
Subordinated Parties to deliver to the Collateral Agent any payment or
collateral received in connection with any Subordinated Claims, set forth in
Section 3.1, shall survive and shall not be in any way affected by the result of
any (a) insolvency, bankruptcy, receivership, liquidation, reorganization,
readjustment, composition or other similar proceeding relating to any
Intercompany Borrower, its property or its creditors as such, (b) proceeding for
any liquidation, dissolution or other winding-up of any Intercompany Borrower,
voluntary or involuntary, whether or not involving insolvency or bankruptcy
proceedings, (c) assignment for the benefit of creditors, (d) other marshalling
of the assets of any Intercompany Borrower or (e) general meeting of creditors
of any Intercompany Borrower, in each case, under the laws of the United States
or any other jurisdiction (any such event, a "Proceeding").

ARTICLE IV
PROCEEDINGS

        Section 4.1    Commencement of Proceedings.    No Subordinated Party
shall commence, or join with any other creditor or creditors of any Intercompany
Borrower in commencing, any Proceeding against such Intercompany Borrower.

        Section 4.2    Payments and Distributions.    In the event of any
Proceeding, until all Obligations shall have been indefeasibly paid in full, any
payment or distribution of any kind or character, whether in cash, property or
securities, which, but for the subordination provisions of this Agreement would
otherwise be payable or deliverable upon or in respect of Subordinated Claims,
shall instead be paid over or delivered to the Collateral Agent in accordance
with Article III and no holder of Subordinated Claims shall receive any such
payment or distribution or any benefit therefrom.

        Section 4.3    Enforcement of Subordinated Claims.    (a) Enforcement by
the Secured Parties. At any Proceeding, until all Obligations shall have been
indefeasibly paid in full, the Secured Parties (or the Collateral Agent on
behalf of the Secured Parties) are hereby irrevocably authorized (but not
required) to:

          (i)  enforce claims comprising Subordinated Claims in the name of the
Subordinated Parties by proof of debt, proof of claim, suit or otherwise;

        (ii)  collect any assets of any Intercompany Borrower distributed,
divided or applied by way of dividend or payment, and any securities issued, in
each case, on account of Subordinated Claims and apply the same, or the proceeds
of any realization upon the same that the Secured Parties in their discretion
elect to effect, to Senior Claims until all Obligations shall have been
indefeasibly paid in full, provided, however, that the Secured Parties shall
render any surplus to the Subordinated Parties or their Affiliates, as their
interests appear, or interplead such surplus with a court of competent
jurisdiction;

        (iii)  vote claims comprising Subordinated Claims to accept or reject
any plan of partial or complete liquidation, reorganization, arrangement,
composition or extension; and

        (iv)  take generally any action in connection with any such Proceeding
which the Subordinated Parties might otherwise take.

        (b)    Cooperation.    The Subordinated Parties shall cooperate fully
with the Secured Parties and perform all acts requested by the Secured Parties
to enable the Secured Parties to enforce any Subordinated Claims pursuant to
clause (a) above, including, without limitation, filing appropriate proofs of
claim and executing and delivering all necessary powers of attorney, assignments
or other instruments.

        (c)    Enforcement by the Subordinated Parties.    After the
commencement of any Proceeding, the Subordinated Parties may inquire in writing
of the Secured Parties whether the Secured Parties

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intend to exercise their rights set forth in clause (a) above with respect to
any Subordinated Claims. Should the Secured Parties fail, within a reasonable
time after receipt of such inquiry, either to file a proof of claim with respect
to any Subordinated Claims and to furnish a copy thereof to the Subordinated
Parties, or to inform the Subordinated Parties in writing that the Secured
Parties intend to exercise their rights to assert such Subordinated Claims in
the manner provided in clause (a) above, the Subordinated Parties may (but shall
not be required to) proceed to file a proof of claim with respect to such
Subordinated Claims and take such further steps with respect thereto, not
inconsistent with this Agreement, as the Subordinated Parties may deem proper.

        (d)    Subrogation.    The Subordinated Parties shall not have any
subrogation or other rights as holders of Senior Claims, and each Subordinated
Party hereby irrevocably waives all such rights of subrogation and all rights of
reimbursement or indemnity whatsoever and all rights of recourse to any security
for any Senior Claims, until such time as all Obligations shall have been
indefeasibly paid in full. Subject to and from and after the indefeasible
payment in full of all Obligations, the Subordinated Parties shall be subrogated
to any rights of the Secured Parties to receive payments or distributions of
cash, property or securities of any Intercompany Borrower applicable to any
Subordinated Claims until all amounts owing on such Subordinated Claims shall be
paid in full.

ARTICLE V
LIMITATION ON ACTIONS

        Section 5.1    Actions Prohibited.    Until all Obligations shall have
been indefeasibly paid in full, the Subordinated Parties shall not, without the
prior written consent of the Secured Parties:

        (a)  take, obtain or hold (or permit anyone acting on its behalf to
take, obtain or hold) any assets of any Intercompany Borrower, whether as a
result of any administrative, legal or equitable action, or otherwise, in
violation of the subordination provisions contained in this Agreement;

        (b)  accelerate payment of any Subordinated Claims or otherwise require
such Subordinated Claims to be paid prior to their stated or scheduled maturity
date;

        (c)  commence, prosecute or participate in (i) any administrative, legal
or equitable action against or involving any Intercompany Borrower relating to
any Subordinated Claims, including, without limitation, any Proceeding, or
(ii) any administrative, legal or equitable action to (a) enforce or collect any
judgment obtained in respect of any Subordinated Claims, (b) enforce or exercise
remedies arising under or pursuant to any Subordinated Claims, (c) enforce or
exercise remedies under or pursuant to any lien or other security interest
securing any Subordinated Claims or (d) enforce or exercise remedies with
respect to any covenant, agreement, representation or other undertaking
contained in any Subordinated Notes; or

        (d)  exercise any other rights or remedies to enforce any Subordinated
Claims, any collateral security provided with respect to such Subordinated
Claims or any covenant, agreement, representation or other undertaking contained
in any Subordinated Notes.

        Section 5.2    Defense in Action.    If the Subordinated Parties, in
violation of the provisions herein set forth, shall commence, prosecute or
participate in any suit, action, case or Proceeding referred to in Section 5.1,
the related Intercompany Borrower may interpose as a defense or plea the
provisions set forth herein, and any holder of any Senior Claims may intervene
and interpose such defense or plea in its own name or in the name of such
Intercompany Borrower, and shall, in any event, be entitled to restrain the
enforcement of the provisions of any Subordinated Claims in its own name or in
the name of such Intercompany Borrower, as the case may be, in the same suit,
action, case or Proceeding or in any independent suit, action, case or
Proceeding.

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ARTICLE VI
SUBORDINATION ABSOLUTE

        Section 6.1    Survival of Rights.    The rights under this Agreement of
the holders of Senior Claims as against the Subordinated Parties shall remain in
full force and effect without regard to, and shall not be impaired or affected
by:

        (a)  any act or failure to act on the part of any Intercompany Borrower;

        (b)  any extension or indulgence in respect of any payment or prepayment
of any Senior Claims or any part thereof or in respect of any other amount
payable to any holder of any Senior Claims;

        (c)  any amendment, modification or waiver of, or addition or supplement
to, or deletion from, or compromise, release, consent or other action in respect
of, any of the terms of any Senior Claims or the Financing Documents;

        (d)  (i) any exercise or non-exercise by the holder of any Senior Claims
of any right, power, privilege or remedy under or in respect of such Senior
Claims, the Financing Documents or the subordination provisions contained
herein, (ii) any waiver by the holder of any Senior Claims of any right, power,
privilege or remedy or of any default in respect of such Senior Claims, the
Financing Documents or the subordination provisions contained herein or
(iii) any receipt by the holder of any Senior Claims or any failure by such
holder to perfect a security interest in, or any release by such holder of, any
security for the payment of such Senior Claims;

        (e)  any merger or consolidation of any Intercompany Borrower or any of
its subsidiaries into or with any other Person, or any sale, lease or transfer
of any or all of the assets of any Intercompany Borrower or any of its
subsidiaries to any other Person;

        (f)    any payment or other distribution to any holder of any Senior
Claims in any Proceeding;

        (g)  absence of any notice to, or knowledge by, the Subordinated Parties
of the existence or occurrence of any of the matters or events set forth in the
foregoing clauses (a) through (f); or

        (h)  any other circumstance.

        Section 6.2    Waivers.    (a) Waiver of Defenses.    Each Subordinated
Party hereby irrevocably waives, in any proceeding by the Secured Parties to
enforce their rights under this Agreement, (i) any defense based on the adequacy
of a remedy at law which might be asserted as a bar to the remedy of specific
performance of this Agreement and (ii) the defense that claims asserted by the
holders of the Initial Lessor Notes pursuant to this Agreement are res judicata
as a result of any decision rendered in any prior Proceeding.

        (b)    Other Waivers.    Each Subordinated Party hereby irrevocably
waives (i) notice of any of the matters referred to in Section 6.1, (ii) all
notices which may be required, whether by statute, rule of law or otherwise, to
preserve intact any rights of any holder of any Senior Claims against any
Intercompany Borrower, including, without limitation, any demand, presentment
and protest, or any proof of notice of nonpayment under any document evidencing
such Senior Claims or under the Financing Documents, (iii) notice of the
acceptance of or reliance on this Agreement by the Secured Parties, (iv) notice
of any renewal, extension or accrual of any Senior Claims, or any loans made or
other action taken in reliance on this Agreement, (v) any right to the
enforcement, assertion or exercise by any holder of any Senior Claims of any
right, power, privilege or remedy conferred in any document evidencing such
Senior Claims or in the Financing Documents, or otherwise, (vi) any requirement
of diligence on the part of any holder of any Senior Claims, (vii) any
requirement on the part of any holder of any Senior Claims to mitigate damages
resulting from any default under any documents evidencing such Senior Claims or
under the Financing

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Documents and (viii) any notice of any sale, transfer or other disposition of
any Senior Claims by any holder thereof.

        Section 6.3    Assent.    Each Subordinated Party hereby irrevocably
assents to (a) any renewal, extension or postponement of the time of payment of
any Senior Claims or any other indulgence with respect thereto, (b) any increase
in the amount of any Senior Claims, (c) any substitution, exchange or release of
collateral for any Senior Claims, (d) the addition or release of any Person
primarily or secondarily liable for any Senior Claims and (e) the provisions of
any instrument, security or other writing evidencing any Senior Claims.

ARTICLE VII
INTERCOMPANY BORROWER OBLIGATIONS

        The provisions of this Agreement are intended solely for the purpose of
defining the relative rights and obligations of the Subordinated Parties and the
Secured Parties. Nothing contained herein (a) is intended to or shall impair, as
among any Intercompany Borrower, its creditors and the related Subordinated
Party, the obligation of such Intercompany Borrower, which is absolute and
unconditional, to pay to such Subordinated Party, as and when the same shall
become due and payable in accordance with its terms, all amounts payable in
respect of any Subordinated Claims, or (b) is intended to affect the relative
rights of such Subordinated Party and creditors of such Intercompany Borrower
other than the Secured Parties.

ARTICLE VIII
MISCELLANEOUS PROVISIONS

        Section 8.1    Waivers, Amendments.    (a) The provisions of this
Agreement may from time to time be amended, modified or waived, if such
amendment, modification or waiver is in writing and consented to by each of the
parties hereto, the holders of the Initial Lessor Notes, each of the Owner
Lessors and each of the Owner Participants.

        (b)  No failure or delay in exercising any power or right under this
Agreement shall operate as a waiver thereof, nor shall any single or partial
exercise of any such power or right preclude any other or further exercise
thereof or the exercise of any other power or right. No notice to or demand on
any party in any case shall entitle it to any notice or demand in similar or
other circumstances. No waiver or approval under this Agreement shall, except as
may be otherwise stated in such waiver or approval, be applicable to subsequent
transactions. No waiver or approval hereunder shall require any similar or
dissimilar waiver or approval thereafter to be granted hereunder.

        Section 8.2    Notices.    Except as otherwise specifically provided
herein, all notices, consents, directions, approvals, instructions, requests and
other communications required or permitted by the terms hereof to be given to
any Person shall be in writing and shall be deemed to have been duly given or
made when delivered if delivered by hand or courier or when received if sent by
mail or telecopy, in each case addressed to the party to which such notice is
required or permitted to be given or made hereunder set forth below its
signature hereto, or such other address as may be specified from time to time by
such party in a notice to the other parties hereto.

        Section 8.3    Severability.    Any provision of this Agreement which is
prohibited or unenforceable in any jurisdiction shall, as to such provision and
such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions of this Agreement
or affecting the validity or enforceability of such provision in any other
jurisdiction.

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        Section 8.4    Headings.    The various headings of this Agreement are
inserted for convenience only and shall not affect the meaning or interpretation
of this Agreement or any provisions hereof or thereof.

        Section 8.5    Execution in Counterparts, Effectiveness.    This
Agreement may be executed by the parties hereto in several counterparts, each of
which shall be deemed to be an original and all of which shall constitute
together but one and the same agreement.

        Section 8.6    Governing Law; Entire Agreement.    THIS AGREEMENT SHALL
IN ALL RESPECTS BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE
STATE OF NEW YORK. This Agreement constitutes the entire understanding among the
parties hereto with respect to the subject matter hereof and supersede any prior
agreements, written or oral, with respect thereto.

        Section 8.7    Successors and Assigns.    (a) This Agreement shall be
binding upon and shall inure to the benefit of the parties hereto and their
respective successors and assigns.

        (b)  Notwithstanding the foregoing, in order to secure the Lessor Notes
of each Owner Lessor, such Owner Lessor will assign and grant a first priority
security interest in favor of its applicable Lease Indenture Trustee in and to
all of such Owner Lessor's right, title and interest in, to and under this
Agreement (other than to the extent relating to Excepted Payments and the rights
to enforce and collect the same). Each of the parties hereto hereby consents to
such assignment and to the creation of such Lien and security interest and
acknowledges receipt of copies of the Lease Indenture, it being understood that
such consent shall not affect any requirement or the absence of any requirement
for any consent of such party under any other circumstances. Unless and until
the Collateral Agent shall have received written notice from the Lease Indenture
Trustee that the Lien of the applicable Lease Indenture has been fully
discharged, the applicable Security Agent shall have the right (i) to directly
receive for application in accordance with the terms of the applicable Lease
Indenture all amounts payable or otherwise distributable under this Agreement to
the applicable Owner Lessor (other than in respect of the Excepted Payments) and
(ii) to exercise the rights of such Owner Lessor under this Agreement (other
than with respect to Excepted Payments and the rights to enforce and collect the
same) to the extent set forth in and subject to the exceptions set forth in the
applicable Lease Indenture.

        Section 8.8    Forum Selection and Consent to Jurisdiction.    ANY
LITIGATION BASED HEREON, OR ARISING OUT OF, UNDER, OR IN CONNECTION WITH, THIS
AGREEMENT, OR ANY COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER
VERBAL OR WRITTEN) OR ACTIONS OF ANY PARTY HERETO SHALL BE BROUGHT AND
MAINTAINED EXCLUSIVELY IN THE COURTS OF THE STATE OF NEW YORK OR IN THE UNITED
STATES DISTRICT COURT FOR THE SOUTHERN DISTRICT OF NEW YORK. EACH PARTY HERETO
HEREBY EXPRESSLY AND IRREVOCABLY SUBMITS TO THE JURISDICTION OF THE COURTS OF
THE STATE OF NEW YORK AND OF THE UNITED STATES DISTRICT COURT FOR THE SOUTHERN
DISTRICT OF NEW YORK FOR THE PURPOSE OF ANY SUCH LITIGATION AS SET FORTH ABOVE
AND IRREVOCABLY AGREES TO BE BOUND BY ANY JUDGMENT RENDERED THEREBY IN
CONNECTION WITH SUCH LITIGATION. EACH PARTY HERETO FURTHER IRREVOCABLY CONSENTS
TO THE SERVICE OF PROCESS BY REGISTERED MAIL, POSTAGE PREPAID, OR BY PERSONAL
SERVICE WITHIN OR WITHOUT THE STATE OF NEW YORK. EACH PARTY HERETO HEREBY
EXPRESSLY AND IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY LAW, ANY
OBJECTION WHICH IT MAY HAVE OR HEREAFTER MAY HAVE TO THE LAYING OF VENUE OF ANY
SUCH LITIGATION BROUGHT IN ANY SUCH COURT REFERRED TO ABOVE AND ANY CLAIM THAT
ANY SUCH LITIGATION HAS BEEN BROUGHT IN AN INCONVENIENT FORUM. TO THE EXTENT
THAT ANY PARTY

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HERETO HAS OR HEREAFTER MAY ACQUIRE ANY IMMUNITY FROM JURISDICTION OF ANY COURT
OF FROM ANY LEGAL PROCESS (WHETHER THROUGH SERVICE OR NOTICE, ATTACHMENT PRIOR
TO JUDGMENT, ATTACHMENT IN AID OF EXECUTION OR OTHERWISE) WITH RESPECT TO ITSELF
OR ITS PROPERTY, SUCH PARTY HEREBY IRREVOCABLY WAIVES SUCH IMMUNITY IN RESPECT
OF ITS OBLIGATIONS UNDER THIS AGREEMENT.

        Section 8.9    Waiver of Jury Trial.    EACH PARTY HEREBY KNOWINGLY,
VOLUNTARILY AND INTENTIONALLY WAIVE ANY RIGHTS THEY MAY HAVE TO A TRIAL BY JURY
IN RESPECT OF ANY LITIGATION BASED HEREON, OR ARISING OUT OF, UNDER, OR IN
CONNECTION WITH, THIS AGREEMENT, OR ANY COURSE OF CONDUCT, COURSE OF DEALING,
STATEMENTS (WHETHER VERBAL OR WRITTEN) OR ACTIONS OF ANY PARTY HERETO. EACH
PARTY ACKNOWLEDGES AND AGREES THAT IT HAS RECEIVED FULL AND SUFFICIENT
CONSIDERATION FOR THIS PROVISION AND THAT THIS PROVISION IS A MATERIAL
INDUCEMENT FOR THE OTHER PARTIES ENTERING INTO THIS AGREEMENT.

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        IN WITNESS WHEREOF, the parties hereto have each caused this Agreement
to be duly executed by their duly authorized officers, all as of the day and
year first above written.

    EDISON MISSION HOLDINGS CO.
 
 
By:
 
/s/  JOHN P. FINNERAN      

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        Name:   John P. Finneran         Title:   Vice President
 
 
Address for Notices:
 
 
18101 Von Karman Avenue
Suite 1700
Irvine, California 92612-1046
 
 
EDISON MISSION FINANCE CO.
 
 
By:
 
/s/  JOHN P. FINNERAN      

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        Name:   John P. Finneran         Title:   Vice President
 
 
Address for Notices:
 
 
18101 Von Karman Avenue
Suite 1700
Irvine, California 92612-1046
 
 
HOMER CITY PROPERTY HOLDINGS, INC.
 
 
By:
 
/s/  STEVEN D. EISENBERG      

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        Name:   Steven D. Eisenberg         Title:   Vice President
 
 
Address for Notices:
 
 
18101 Von Karman Avenue
Suite 1700
Irvine, California 92612-1046

10

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CHESTNUT RIDGE ENERGY CO.
 
 
By:
 
/s/  JOHN P. FINNERAN      

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        Name:   John P. Finneran         Title:   Vice President
 
 
Address for Notices:
 
 
18101 Von Karman Avenue
Suite 1700
Irvine, California 92612-1046
 
 
MISSION ENERGY WESTSIDE, INC.
 
 
By:
 
/s/  JOHN P. FINNERAN      

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        Name:   John P. Finneran         Title:   Vice President
 
 
Address for Notices:
 
 
18101 Von Karman Avenue
Suite 1700
Irvine, California 92612-1046
 
 
EME HOMER CITY GENERATION L.P.
 
 
By:
 
Mission Energy Westside, Inc.,
    its General Partner
 
 
By:
 
/s/  STEVEN D. EISENBERG      

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        Name:   Steven D. Eisenberg         Title:   Vice President
 
 
Address for Notices:
 
 
18101 Von Karman Avenue
Suite 1700
Irvine, California 92612-1046
 
 
UNITED STATES TRUST COMPANY
    OF NEW YORK, as Collateral Agent
 
 
By:
 
/s/  CHRISTOPHER J. GRELL      

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        Name:   Christopher J. Grell         Title:   Authorized Signer
 
 
Address for Notices:
 
 
114 West 47th Street
25th Floor
New York, New York 10036

11

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QuickLinks

Exhibit 10.23.1

AMENDED AND RESTATED INTERCOMPANY LOAN SUBORDINATION AGREEMENT
RECITALS