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Exhibit 10.2

AMENDED AND RESTATED
MASTER PURCHASE, SALE AND SERVICES AGREEMENT

        This AMENDED AND RESTATED MASTER PURCHASE, SALE AND SERVICES AGREEMENT
(together with the Schedules attached hereto from time to time, this
"Agreement") is entered into this 27th day of April, 2004 between MIDWEST
GENERATION, LLC, a Delaware limited liability company ("MWGen"), and EDISON
MISSION MARKETING & TRADING, INC., a California corporation ("EMMT"). Each of
MWGen and EMMT may be referred to herein as a "Party" and together shall be
referred to as the "Parties".

        WHEREAS, MWGen is engaged in the business of owning or leasing and
operating the following power generation facilities (collectively, the
"Facilities"): (a) six coal-fired generating plants consisting of 5,646 MW,
which include Powerton, Joliet, Will County, Waukegan, Crawford, and Fisk;
(b) the Collins gas and oil-fired generating station consisting of 2,698 MW (the
"Collins Station"); and (c) a group of on-site generating peakers consisting of
740 winter MW (467 summer MW) and off-site generating peakers consisting of 657
winter MW (467 summer MW).

        WHEREAS, EMMT is engaged, among other things, in the business of
marketing, trading, buying and selling Energy, capacity, fossil fuels, emissions
allowances and other energy-related physical and financial commodities and
products, and derivatives thereof.

        WHEREAS, the Parties may enter into physical or financial transactions
related to the purchase and sale of Energy, fossil fuels, emissions allowances
and other energy-related products, and physical and financial derivatives
thereof related to the Facilities (the "Products"), and MWGen desires, under
certain circumstances, to use EMMT's services to facilitate transactions with
third parties related to the purchase and sale of such Products (all
transactions described in this paragraph are, collectively, the "Transactions").

        WHEREAS, the Parties intend that all Transactions shall be based on
Back-to-Back Transactions between EMMT and unrelated third parties (except for
Transactions in which EMMT acts as MWGen's disclosed agent with third parties
("Disclosed Agent Transactions")), and that no Transactions hereunder shall
result from or relate to EMMT's proprietary trading portfolio.

        WHEREAS, the Parties entered into a Master Purchase, Sale and Service
Agreement, dated as of                        , 2001 (the "Original Master
Purchase and Sale Agreement"), and the Parties desire to amend and restate the
Original Master Purchase and Sale Agreement in accordance with the terms hereof.

        NOW, THEREFORE, in consideration of the foregoing, and for other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Parties covenant and agree as follows:

ARTICLE I
SCOPE OF AGREEMENT

        1.1.  Scope of Agreement. Each Transaction shall be effectuated and
evidenced in accordance with this Agreement and the Schedules hereto, which
Schedules shall constitute a part of this Agreement. The Parties are relying
upon the fact that all Transactions, together with this Agreement and the
Schedules hereto, shall constitute a single integrated agreement. This
Agreement, including the Schedules hereto, shall govern all Transactions between
the Parties for the term of this Agreement unless, in the case of any
Transaction, the Parties shall expressly state otherwise. The Parties' rights
and obligations with respect to any Product will be further described in the
Schedule for such Product, as such Schedules may be entered into between the
Parties from time to time. Schedules may be added,

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deleted or amended from time to time as agreed by the Parties in writing. In the
case of Energy sales from MWGen to EMMT, such sales shall be for a duration of
no more than one year, unless agreed to by the Parties in writing. In case of
any conflict between this Agreement and any Schedule, the Schedule shall govern.

        1.2.  Transaction Procedures.

        (a)   The transaction price ("Transaction Price"), quantity
("Transaction Quantity") and delivery point ("Delivery Point") of each Product
purchased or sold by EMMT and MWGen under this Agreement shall be the price
established in a Back-to-Back Transaction between EMMT and an unrelated third
party (unless such purchase or sale is a Disclosed Agent Transaction).

        (b)   Each Transaction hereunder shall be designated by EMMT as a "hedge
transaction" in EMMT's Energy Trading System or other applicable software at or
before the execution of its corresponding Back-to-Back Transaction (except for
Disclosed Agent Transactions, which shall be designated at the time of such
Transaction), and shall be subsequently evidenced by a written notice (a
"Transaction Notice") from EMMT that includes reasonable detail of such
Transaction, including the Transaction Price, Transaction Quantity, and Delivery
Point. Such notice may be provided (i) in a monthly accounting journal entry; or
(ii) in such other form as agreed by the Parties in writing. Any additional
information to be provided for Transactions for each Product shall be specified
in the Schedule that applies to such Product.

        (c)   The Transactions will be entered into by EMMT and MWGen according
to the guidelines established and amended from time to time (the "Risk
Management Guidelines") by the Americas Operating, Commercial, Risk Management
Committee or its successor, which includes senior officers and representatives
of both EMMT and MWGen. EMMT shall be required to use commercially reasonable
care in developing and executing Transactions so as to comply with the Risk
Management Guidelines. EMMT shall advise MWGen on marketing, fuel procurement
and other business strategies from time to time.

        1.3.  Term.

        (a)   This Agreement shall commence on the date hereof (the "Effective
Date") and shall remain in effect until terminated by either Party upon thirty
(30) days prior written notice, or as the Parties mutually agree in writing;
provided, however, that this Agreement shall remain in effect with respect to
any Transaction(s) entered into prior to the effective date of the termination
until both Parties have fulfilled their obligations with respect to such
Transaction(s).

        (b)   In the event either Party shall (i) make an assignment or any
general arrangement for the benefit of creditors, (ii) default in the payment of
any obligation to the other Party, (iii) file a petition or otherwise commence,
authorize, or acquiesce in the commencement of a proceeding or cause under any
bankruptcy or similar law for the protection of creditors or have such petition
filed or proceeding commenced against it, (iv) otherwise become bankrupt or
insolvent (however evidenced), or (v) be unable to pay its debts as they fall
due (collectively, "Bankruptcy Proceedings"), then the other Party shall have
the right either to withhold and/or suspend deliveries or payment, or to
terminate this Agreement without prior notice, in addition to any and all other
remedies available hereunder. Either Party may immediately suspend deliveries to
the other Party in the event such other Party has not paid any amount due to the
suspending Party hereunder on or before the fifth Business Day following the
date such payment is due.

ARTICLE II
OBLIGATIONS OF THE PARTIES; TITLE

        2.1.  Title: Risk of Loss. As between the Parties, the seller of such
Product ("Seller") shall be deemed to be in exclusive control (and responsible
for any damages or injury caused thereby) of any

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Product prior to the Delivery Point of the Product and the purchaser of such
Product ("Buyer") shall be deemed to be in exclusive control (and responsible
for any damages or injury caused thereby) of the Product at and from the
Delivery Point of the Product, except for Disclosed Agent Transactions (in which
case MWGen shall have such control and responsibility with respect to such
Product as the contract entered into by MWGen or EMMT on MWGen's behalf may
specify). Each Party warrants that it will deliver Products sold by it hereunder
to the other Party, free and clear of all liens, claims, and encumbrances
arising prior to the Delivery Point. Title to and risk of loss related to the
Product shall transfer from the Seller to the Buyer at the Delivery Point.

2.2Indemnity. MWGen and EMMT shall indemnify, defend and hold harmless each
other from any Claims (as defined herein) arising from any act or incident
occurring when title to the Product is vested in the indemnifying Party;
provided that, MWGen shall not be obligated to indemnify, defend and hold
harmless EMMT from any claims arising from any negligent act or omission of EMMT
when title to a Product is vested in MWGen but is under the control of EMMT in
Disclosed Agent Transactions.

2.3Rights of EMMT Subject to Certain Other Agreements. Notwithstanding any other
provision of this Agreement to the contrary, the rights of EMMT under this
Agreement, if applicable, are subject to the rights of ExGen under the Power
Purchase Agreements; (ii) the obligations of MWGen under the Power Purchase
Agreements; and (iii) the terms and provisions of the MWGen Financing
Agreements.

ARTICLE III
PRICING AND PAYMENT

        3.1.  Billing and Payment. Unless otherwise agreed in the specific
Product Schedules, EMMT shall send a settlement statement or otherwise make
available a record to MWGen by the 25th day of each month in respect of
purchases and sales of each Product during the preceding month; such statement
shall itemize in reasonable detail the amounts owed, if any, by each Party to
the other, including the net amount due by either Party. The Party owing a net
payment shall render payment by wire transfer in immediately available funds by
the 30th day of each month to such account as may be specified by the payee from
time to time. MWGen shall use its best efforts to coordinate payments with EMMT
as needed to meet EMMT's payment obligations to third parties. If such day is
not a Business Day, then payment shall be due on the next following Business
Day.

        3.2.  Off Set. All outstanding Transactions under this Agreement and the
obligations to make payment in connection therewith or under any other agreement
between the Parties may be offset against each other, netted, set-off or
recouped therefrom.

        3.3   Audit. Each Party (and its representative(s)) has the right, at
its sole expense and during normal working hours, to examine the records of the
other Party to the extent reasonably necessary to verify the accuracy of any
statement, charge or computation made pursuant to this Agreement. If requested,
a Party shall provide to the other Party statements evidencing the quantities of
Products delivered hereunder. If any such examination reveals any inaccuracy in
any statement, the necessary adjustments in such statement and the payments
thereof will be promptly made and shall bear interest calculated at the Interest
Rate from the date the overpayment or underpayment was made until paid;
provided, however, that no adjustment for any statement or payment will be made
unless objection to the accuracy thereof was made prior to the lapse of one
(1) year from the rendition thereof; and provided further that this Section 3.3
will survive any termination of the Agreement for a period of one (1) year from
the date of such termination for the purpose of such statement and payment
objections.

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ARTICLE IV
EVENTS OF DEFAULT

        4.1.  Events of Default. If either Party shall fail to observe or
perform any material term, covenant or condition of this Agreement (except for
bankruptcy proceedings which are governed by Section 1.3(b) hereof) and such
failure shall remain uncured for a period of ten (10) days after receipt of
written notice thereof by the other Party (each such failure shall constitute an
"Event of Default"), then, upon the occurrence of any such Event of Default, the
non-defaulting Party may, in addition to the other rights and remedies provided
for in this Agreement, immediately terminate this Agreement by giving the
defaulting Party written notice of such termination, and upon the giving of such
notice, all rights of the defaulting Party and all obligations of the
non-defaulting Party under this Agreement shall cease, except to the extent
otherwise provided in Section 4.2 or Section 5.1. The defaulting Party shall pay
upon demand all costs, expenses, losses, expenditures and damages (including,
without limitation, reasonable attorneys' fees) incurred by or on behalf of the
non-defaulting Party in connection with any Event of Default, together with
interest thereon at the Interest Rate from the date of the Event of Default.

        4.2.  Survival. The termination of this Agreement pursuant to
Section 4.1 shall in no event relieve either Party of its liability and
obligations hereunder that accrued prior to such termination, all of which shall
survive any such termination.

        4.3.  Remedies Cumulative Waivers.

        (a)   If an Event of Default shall have occurred and be continuing, the
non-defaulting Party shall have, in addition to the rights and remedies provided
for in this Section 4, all rights and remedies available at law, in equity or
otherwise.

        (b)   No failure to exercise and no delay in exercising, on the part of
the non- defaulting Party, any right, remedy, power or privilege under this
Agreement shall operate as a waiver thereof; nor shall any single or partial
exercise of any right, remedy, power or privilege under this Agreement preclude
any other or further exercise thereof or the exercise of any other right,
remedy, power or privilege. The rights, remedies, powers and privileges provided
in this Agreement, including with particularity Section 4.1, are cumulative and
not exclusive of any rights, remedies, powers, and privileges provided by law.

        4.4.  Right to Cure. The non-defaulting Party, without waiving or
releasing any obligation or Event of Default, may (but shall be under no
obligation to) remedy any Event of Default for the account of and at the sole
cost and expense of the defaulting Party. All reasonable out-of-pocket costs and
expenses so incurred (including, without limitation, reasonable attorneys'
fees), together with interest thereon at the Interest Rate from the date on
which such sums or expenses are paid by the non-defaulting Party, shall be paid
by the defaulting Party to the non-defaulting Party on demand.

ARTICLE V
INDEMNITY

        5 .1. Indemnification. Each Party shall indemnify, hold harmless and
defend the other Party, its officers, directors, employees, assignees,
affiliates (other than the indemnifying Party), successors and assigns (each an
"Indemnified Person") from and against any and all claims (including without
limitation third party claims for personal injury or real or personal property
damage), losses, damages, demands, liabilities, fines, penalties, charges,
administrative and judicial proceedings (including informal proceedings) and
orders, judgments, remedial action, requirements, enforcement actions of any
kind, and all reasonable and documented costs and expenses incurred in
connection therewith (including but not limited to reasonable and documented
attorneys' and/or paralegals' fees and expenses) (collectively, "Claims"),
arising in whole or in part, out of default in the performance of, or the
negligent

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performance of, any obligations of such Party under this Agreement; provided,
however, such Party shall not be required to indemnify any Indemnified Person
under this Section 5.1 for any Claim to the extent resulting from the misconduct
or gross negligence of such Indemnified Person. It is expressly understood and
agreed that the indemnity provided for herein shall survive the expiration or
termination of and shall be separate and independent from any remedy under this
Agreement.

        5.2.  Duty to Mitigate. Each Party agrees that it has a duty to mitigate
damages and covenants that it will use commercially reasonable efforts to
minimize any damages it may incur as a result of the other Party's performance
of non-performance of this Agreement.

ARTICLE VI
DEFINITIONS

        6.1   Definitions.

        "AAA" has the meaning set forth in Section 7.3.

        "Ancillary Services" means regulation, spinning reserve, voltage support
and black start services supporting transmission of Energy from generation
resources to loads while maintaining reliable operation of the transmission
grid.

        "Back-to-Back Transactions" means transactions with unrelated third
parties that are not Disclosed Agent Transactions pursuant to which a Product is
either (a) purchased by EMMT (for resale to MWGen), or (b) sold by EMMT (with
the intent to acquire the Product sold from MWGen), and any other transactions
with unrelated third parties which are designated pursuant to Section 1.2 as
"hedge transactions".

        "Bankruptcy Proceedings" has the meaning set forth in Section 1.3.

        "Business Day" shall be any day on which Federal Reserve banks are open
for regular commercial business in New York, New York.

        "Buyer" has the meaning set forth in Section 2.1.

        "Capacity" means the right, but not the obligation, to schedule and take
Merchantable Energy.

        "Claims" has the meaning set forth in Section 5.1.

        "Credit Agreements" means (a) that certain Credit Agreement, dated as of
April 27, 2004, among Edison Mission Energy, certain commercial lending
institutions named therein, and Citicorp North America, Inc., as administrative
agent for the lenders thereunder and (b) that certain Credit Agreement, dated as
of April 27, 2004, among MWGen, certain commercial lending institutions, and
Citicorp North America, Inc. as administrative agent for the lenders thereunder.

        "Delivery Point" has the meaning set forth in Section 1.2.

        "Disclosed Agent Transaction" has the meaning set forth in the fourth
recital of this Agreement.

        "Dispute" has the meaning set forth in Section 7.3.

        "Effective Date" has the meaning set forth in Section 1.3.

        "Energy" means Merchantable Energy, Capacity, and/or Ancillary Services.

        "Event of Default" has the meaning set forth in Section 4.1.

        "ExGen" means Exelon Generation Company, as assignee of Commonwealth
Edison Company.

        "Facilities" has the meaning set forth in the preamble to this
Agreement.

        "Indemnified Person" has the meaning set forth in Section 5.

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        "Indenture" means that certain Trust Indenture, dated as of April 27,
2004, between MWGen and Bank of New York, as trustee.

        "Interest Rate" means, for any date, the lesser of (i) two percent over
the per annum rate of interest equal to the prime lending rate as may from time
to time be published in the Wall Street Journal under "Money Rates" and (ii) the
maximum lawful interest rate permitted by applicable law.

        "Joliet Participation Agreements" means, collectively, (a) that certain
Participation Agreement, dated as of August 17, 2000 among Midwest, Joliet Trust
I, Wilmington Trust Company, as the Owner Trustee, Joliet Generation I, LLC,
Edison Mission Energy ("EME"), United States Trust Company of New York as Lease
Indenture Trustee and United States Trust Company of New York as Pass Through
Trustees and (b) that certain Participation Agreement, dated as of August 17,
2000 among Midwest, Joliet Trust II, Wilmington Trust Company, as the Owner
Trustee, Joliet Generation II, LLC, EME, United States Trust Company of New York
as Lease Indenture Trustee and United States Trust Company of New York as Pass
Through Trustees.

        "Leases" means (a) that certain Facility Lease Agreement (T1), dated as
of August 17, 2000, between Nesbitt Asset Recovery, Series P-1 (f/k/a Powerton
Trust I), as Owner Lessor, and MWGen, as Facility Lessee; (b) that certain
Facility Lease Agreement (T2), dated as of August 17, 2000, between Powerton
Trust II, as Owner Lessor, and MWGen, as Facility Lessee; (c) that certain
Facility Lease Agreement (T1), dated as of August 17, 2000, between Nesbitt
Asset Recovery, Series J-1 (f/k/a Joliet Trust I), as Owner Lessor, and MWGen,
as Facility Lessee; (d) that certain Facility Lease Agreement (T2), dated as of
August 17, 2000, between Joliet Trust II, as Owner Lessor, and MWGen, as
Facility Lessee; (e) that certain Facility Site Lease and Easement Agreement
(T1), dated as of August 17, 2000, between MWGen, as Ground Lessor, and Nesbitt
Asset Recovery, Series P-1 (f/k/a Powerton Trust I), as Ground Lessee; (f) that
certain Facility Site Lease and Easement Agreement (T2), dated as of August 17,
2000, between MWGen, as Ground Lessor, and Powerton Trust II, as Ground Lessee;
(g) that certain Facility Site Lease and Easement Agreement (T1), dated as of
August 17, 2000, between MWGen, as Ground Lessor, and Nesbitt Asset Recovery,
Series J-1 (f/k/a Joliet Trust I), as Ground Lessee; (h) that certain Facility
Site Lease and Easement Agreement (T2), dated as of August 17, 2000, between
MWGen, as Ground Lessor, and Joliet Trust II, as Ground Lessee; (i) that certain
Facility Site Sublease Agreement (T1), dated as of August 17, 2000, between
Nesbitt Asset Recovery, Series P-1 (f/k/a Powerton Trust I), as Ground
Sublessor, and MWGen, as Ground Sublessee; (j) that certain Facility Site
Sublease Agreement (T2), dated as of August 17, 2000, between Powerton Trust II,
as Ground Sublessor, and MWGen, as Ground Sublessee; (k) that certain Facility
Site Sublease Agreement (T1), dated as of August 17, 2000, between Nesbitt Asset
Recovery, Series J-1 (f/k/a Joliet Trust I), as Ground Sublessor, and MWGen, as
Ground Sublessee; and (l) that certain Facility Site Sublease Agreement (T2),
dated as of August 17, 2000, between Joliet Trust II, as Ground Sublessor, and
MWGen, as Ground Sublessee.

        "Merchantable Energy" means electric energy of the character commonly
known as three-phase, sixty-hertz electric energy that is delivered at the
nominal voltage of the delivery point.

        "MWGen Financing Documents" means the Credit Agreements, the Indenture
and the Participation Agreements and other documents executed in connection with
the Credit Agreements, the Indenture and the Participation Agreements.

        "Participation Agreements" means, collectively, the Powerton
Participation Agreements and the Joliet Participation Agreements.

        "Power Purchase Agreements" means, collectively, (a) that certain Power
Purchase Agreement dated as of December 15,1999, between ExGen and MWGen with
respect to the Crawford, Fisk, Waukegan, Will County, Joliet and Powerton
Generating Stations, (b) that certain Amended and Restated Power Purchase
Agreement dated as of September 13, 2000, between ExGen and MWGen with respect
to the

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Collins Generating Station, and (c) that certain Power Purchase Agreement dated
as of December 15,1999, between ExGen and Seller with respect to the Crawford,
Fisk, Waukegan, Calumet, Joliet, Bloom, Electric Junction, Sabrooke and Lombard
Peaking Units.

        "Powerton Participation Agreements" means, collectively, (a) that
certain Participation Agreement, dated as of August 17, 2000 among Midwest,
Powerton Trust I, Wilmington Trust Company, as the Owner Trustee, Powerton
Generation I, LLC, EME, United States Trust Company of New York as Lease
Indenture Trustee and United States Trust Company of New York as Pass Through
Trustees and (b) that certain Participation Agreement, dated as of August 17,
2000 among Midwest, Powerton Trust II, Wilmington Trust Company, as the Owner
Trustee, Powerton Generation II, LLC, EME, United States Trust Company of New
York as Lease Indenture Trustee and United States Trust Company of New York as
Pass Through Trustees.

        "Product(s)" has the meaning set forth in the Third Recital to this
Agreement.

        "Risk Management Guidelines" has the meaning set forth in Section 1.2.

        "Seller" has the meaning set forth in Section 2.1.

        "Transaction" has the meaning set forth in the Third Recital to this
Agreement.

        "Transaction Notice" has the meaning set forth in Section 1.2.

        "Transaction Price" has the meaning set forth in Section 1.2.

        "Transaction Quantity" has the meaning set forth in Section 1.2.

        6.2   Reference to Other Agreements. Unless otherwise indicated, any
reference to any agreement or instrument will be deemed to include a reference
to that agreement or instrument as assigned, amended, supplemented, amended and
restated, or otherwise modified and in effect from time to time or replaced in
accordance with the terms of this Agreement.

ARTICLE VII
MISCELLANEOUS

        7.1   Notices. All notices, requests, statements, payments, and other
communications required or permitted by the terms hereof to be given to any
person shall be made as specified in Annex I hereto. Notices required to be in
writing shall be delivered by letter, facsimile, or other documentary form.
Notice by facsimile or hand delivery shall be deemed to have been received by
the close of the Business Day on which it was transmitted or hand delivered
(unless transmitted or hand delivered after close of business in which case it
shall be deemed received at the close of the next Business Day). Notice by
overnight mail or courier shall be deemed to have been received two (2) Business
Days after it was sent. A Party may change its addresses by providing written
notice of same in accordance herewith.

        7.2.  Successors and Assigns. Neither Party shall assign this Agreement
or its rights hereunder without the prior written consent of the other Party,
which consent shall not be unreasonably withheld or delayed; provided that,
MWGen or its successors or permitted assigns may collaterally assign any or all
of its rights, title and interests hereunder without EMMT's consent to any
person, corporation, lender, trust company, association or other business or
governmental entity or its respective successor as security in connection with
obtaining or arranging financing (including without limitation any financing
contemplated by the MWGen Financing Documents). This Agreement shall be binding
upon and inure to the benefit of MWGen, EMMT and their permitted successors and
assigns. Unless otherwise agreed to by the Parties, in a separate writing, no
permitted assignment described above shall relieve the assigning Party from any
of its obligations under this Agreement.

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        7.3.  Binding Arbitration. The Parties shall attempt to resolve any
dispute, controversy, difference, or claim arising between them concerning the
interpretation, performance, or enforcement of this Agreement (a "Dispute")
through direct discussion. If, in the sole opinion and discretion of either
Party, such discussion is unsuccessful, such Party shall submit the Dispute to
binding arbitration, and the binding arbitration shall be held in Los Angeles,
California. Unless otherwise agreed by the Parties, the Dispute shall be
submitted to the American Arbitration Association ("AAA") for binding
arbitration pursuant to the commercial arbitration rules of the AAA.

        7.4.  Governing Law. THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS OF
THE PARTIES UNDER THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, WITHOUT
REGARD TO CONFLICTS OF LAWS PRINCIPLES.

        7.5.  Amendments. The Parties may from time to time enter into written
amendments, supplements or modifications hereto.

        7.6.  Counterparts. This Agreement may be executed in any number of
separate counterparts and all of said counterparts taken together shall be
deemed to constitute one and the same instrument.

        7.7.  Severability. Any provision of this Agreement that is prohibited
or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

        7.8.  Headings and Table of Contents. The headings and table of contents
contained in this Agreement are for convenience of reference only and shall not
limit or otherwise affect the meaning hereof.

        7.9.  Amendment and Restatement. The Original Master Purchase and Sale
Agreement is, as of the date hereof, hereby superseded in its entirety by this
Agreement, which has been executed in renewal, amendment, restatement and
modification of, but not in extinguishment of, the obligations under the
Original Master Purchase and Sale Agreement; provided that such Original Master
Purchase and Sale Agreement shall survive in respect of Transactions between the
Parties that were entered into prior to the execution and delivery of this
Agreement until all Parties have fulfilled all of their obligations with respect
to such Transaction(s).

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

    MlDWEST GENERATION, LLC,
a Delaware limited liability company
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President        
 
 
EDISON MISSION MARKETING & TRADING, INC.,
a California corporation
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John. P. Finneran, Jr.
Title: Vice President        

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ANNEX I

NOTICES

MWGEN:

NOTICES & CORRESPONDENCE
Midwest Generation LLC
One Financial Place
440 South LaSalle Street Suite 3500
Chicago, IL 60605
Attn: Georgia R. Nelson
Facsimile No.: (312) 581-6111

BILLING STATEMENTS
Midwest Generation LLC
One Financial Place
440 South LaSalle Street Suite 3500
Chicago, IL 60605
Attn: Carlos Mercado
Facsimile No.: (312) 583-4946

PAYMENTS Bank: Citibank, N.A.
One Penn's Way
New Castle Delaware 19720 ABA Routing #: 031100209
Beneficiary: Midwest Generation, LLC
Acct. No.: 3866-0098
Attention: Kristen Cale

EMMT:

NOTICES & CORRESPONDENCE
Edison Mission Marketing & Trading, Inc.
160 Federal Street
Boston, MA 02110-1776
(617) 912-6003 (Facsimile)
Attention: General Counsel

PAYMENTS
Edison Mission Marketing & Trading, Inc.
160 Federal Street
Boston, MA 02110-1776
(617) 912-5702 (Facsimile)
Attention: Trade Accounting
Bank: Fleet Bank
ABA Routing #011-500-010
Acct No.: 056-225-6897
Account of: EMMT—Trade Account

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SCHEDULE A TO AMENDED AND RESTATED
MASTER PURCHASE, SALE AND SERVICES AGREEMENT
(ENERGY PURCHASE AND SALE SCHEDULE)

        This SCHEDULE A TO AMENDED AND RESTATED MASTER PURCHASE, SALE, AND
SERVICES AGREEMENT (ENERGY PURCHASE AND SALE) (this "Energy Schedule") is
entered into this 27th day of April, 2004 between MIDWEST GENERATION, LLC, a
Delaware limited liability company ("MWGen"), and EDISON MISSION MARKETING &
TRADING, INC., a California corporation ("EMMT"). Each of MWGen and EMMT may be
referred to herein as a "Party" and together shall be referred to as the
"Parties".

        WHEREAS, the Parties entered into an Amended and Restated Master
Purchase, Sale and Services Agreement of even date herewith (the "Agreement"),
which provides that Schedules might be added thereto from time to time setting
forth the terms and conditions upon which the Parties would buy and sell
Products from one another and facilitate each other's entering into Transactions
with third parties;

        WHEREAS, the Parties desire to add this Energy Schedule to the Agreement
to provide for the purchase and sale of Energy from MWGen to EMMT and for the
facilitation of the ExGen Transactions (as hereafter defined);

        WHEREAS, all capitalized terms used in this Energy Schedule that are
defined in the Agreement shall have the respective meanings herein given to such
terms in the Agreement;

        NOW, THEREFORE, in consideration of the foregoing, and for other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Parties covenant and agree as follows:

ARTICLE 1
SCOPE OF AGREEMENT

        1.1.  Scope of Agreement.

        (a)   Pursuant to and subject to the terms and conditions set forth
herein, the Parties agree that EMMT will, as MWGen's agent, arrange for the sale
by MWGen and delivery to ExGen of all Energy required to be sold to ExGen under
the Power Purchase Agreements (the "ExGen Transactions"). For the purposes of
this Energy Schedule, all ExGen Transactions are considered Disclosed Agent
Transactions.

        (b)   In addition to facilitating the ExGen Transactions, EMMT shall
purchase from MWGen, for resale to unrelated third party purchasers, all of the
remaining output of the Facilities. EMMT and MWGen may also enter into other
transactions for the purchase and sale of Energy from time to time. Energy sales
from MWGen to EMMT shall be for a duration of no more than one year, except for
the Transactions in which EMMT acts as MWGen's agent, including, but not limited
to, ExGen Transactions (as defined herein), or unless agreed to by the Parties
in writing.

        (c)   EMMT may also enter into financial hedge transactions related to
the Energy output of the Facilities from time to time.

        (d)   All Transactions described in subsections (a) through (c) above
(collectively, "Energy Transactions") shall be entered into by EMMT and MWGen
according to the guidelines established and amended from time to time (the "Risk
Management Guidelines") by the EMMT Risk Management Committee, which is
comprised of senior officers and representatives of both EMMT and MWGen. EMMT
shall be required to use commercially reasonable care in developing and
executing Energy Transactions so as to comply with the Risk Management
Guidelines. EMMT shall advise MWGen on marketing and other business strategies
from time to time.

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        (e)   The terms and conditions of the Agreement shall apply to Energy
Transactions entered into pursuant to this Energy Schedule, provided that, in
case of any conflict between the Agreement and this Energy Schedule, this Energy
Schedule shall govern. Energy Transactions in which MWGen sells Energy to EMMT
other than ExGen Transactions in which EMMT acts as MWGen's agent shall be for a
duration of no more than one year, unless agreed to by the Parties in writing.

        1.2.  Transaction Procedures and Information.

        (a)   MWGen shall promptly deliver all material information related to
the condition and output of the Facilities or as otherwise reasonably requested
by EMMT from time to time and promptly deliver to EMMT security coordinator,
reliability region, independent system operator, regional transmission
organizations, governmental authorities (collectively, "Reliability
Organizations"), and other third party notices or communications. MWGen shall
also designate EMMT to Reliability Organizations as having any and all authority
necessary to effectuate the Transactions provided for in this Energy Schedule.

        (b)   The transaction price ("Transaction Price"), quantity
("Transaction Quantity") and delivery point ("Delivery Point") of Energy
purchased or sold by EMMT and MWGen under this Agreement, and the terms and
conditions of any financial transaction entered into under this Agreement, shall
be established in a Back-to-Back Transaction between EMMT and an unrelated third
party (except for Disclosed Agent Transactions). Each Energy Transaction
hereunder shall be designated by EMMT as a "hedge transaction" in EMMT's Energy
Trading System or other applicable software at or before the execution of its
corresponding Back-to-Back Transaction (except for Disclosed Agent Transactions,
which shall be designated at the time of such Transaction), and shall be
subsequently evidenced by a written notice (a "Transaction Notice") from EMMT
that includes reasonable detail of such Transaction, including the Transaction
Price, Transaction Quantity, and Delivery Point. Such notice may be provided
(i) in a monthly accounting journal entry; or (ii) in such other form as agreed
by the Parties in writing.

        1.3.  Term.

        (a)   This Energy Schedule shall commence on the date hereof (the
"Schedule Effective Date") and shall remain in effect until terminated by either
Party upon thirty (30) days prior written notice, or as the Parties mutually
agree in writing; provided, however, that this Energy Schedule shall remain in
effect with respect to any Transaction(s) entered into prior to the effective
date of the termination until both Parties have fulfilled their obligations with
respect to such Transaction(s).

        (b)   This Energy Schedule shall terminate automatically upon a default
by MWGen under the Leases or any MWGen Financing Document, provided that the
Parties shall fulfill all of their obligations with respect to Transactions
entered into prior to such termination.

ARTICLE II
OBLIGATIONS OF THE PARTIES; TITLE

        2.1.  Delivery Point. The Delivery Point shall be the bus bar at the
Facility generating the energy for delivery unless the Parties agree otherwise.
With respect to each Transaction (except for Disclosed Agent Transactions), the
selling Party ("Seller") shall sell and deliver, or cause to be delivered, and
the buying Party ("Buyer") shall purchase and receive, or cause to be received,
the Transaction Quantity at the Delivery Point.

        2.2.  Dispatch Procedures. The Parties shall develop procedures for
coordinating the dispatch of Energy at the Delivery Points pursuant to this
Energy Schedule.

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        2.3.  Title: Risk of Loss: and Indemnity. For the purposes of
Section 2.1 of the Agreement, EMMT shall act solely as MWGen's agent with
respect to all ExGen Transactions.

        2.4.  Force Majeure. If Seller or Buyer is rendered unable by Force
Majeure to carry out, in whole or in part, its obligations under a Transaction
and Seller or Buyer, as the case may be, gives notice and full details of the
event to Buyer as soon as practicable after the occurrence of the event, then
during the pendency of such Force Majeure but for no longer period, the
obligations of Seller or Buyer as the case may be (other than the obligations to
make payments then due or becoming due with respect to performance prior to the
event) shall be suspended to the extent required. The Party claiming Force
Majeure shall remedy the Force Majeure with all reasonable dispatch.

        2.5.  Failure to Deliver.

        (a)   In Disclosed Agent Transactions, MWGen shall reimburse EMMT for
any charges, penalties or damages EMMT incurs as a result of MWGen's failure to
deliver or receive the Transaction Quantity to such third parties.

        (b)   In Transactions other than Disclosed Agent Transactions, unless
excused by Force Majeure or Buyer's failure to receive Energy, if Seller fails
to deliver all or part of the Transaction Quantity, Seller shall pay Buyer for
each part of the Transaction Quantity not delivered an amount equal to either
(i) the sum of (x) two cents ($0.02) for each megawatt hour of Energy purchased
by the Buyer to replace Energy the Seller has failed to deliver and (y) the
price at which Buyer, acting in a commercially reasonable manner, purchases
substitute Energy not delivered by Seller (plus any additional transmission
charges, if any, incurred by Buyer to the Delivery Point) or (ii) absent a
purchase, the market price for such quantity at such Delivery Point as
determined by Buyer in a commercially reasonable manner.

        (c)   Payments pursuant to this Section 2.5 shall be due and payable by
Seller according to the payment terms in Section 3.1 of the Agreement.

ARTICLE III
PRICING AND PAYMENT

        3.1.  Price and Reimbursement.

        (a)   For sales by MWGen to EMMT, EMMT shall pay MWGen the Transaction
Price for the Transaction Quantity less the Reimbursements (as defined herein).
For sales by EMMT to MWGen, MWGen shall pay EMMT the Transaction Price for the
Transaction Quantity plus the Reimbursements.

        (b)   With respect to any Transaction Quantity, the term
"Reimbursements" shall mean (i) $0.02/MWh ($0.02/MW-day for Capacity) for each
megawatt hour (or MW-day in the case of Capacity) of the Transaction Quantity;
(ii) FERC fees accrued on such Transaction Quantity; (iii) broker fees incurred
with regard to such Transaction Quantity; (iv) any power pool, independent
system operator, regional transmission operator, or security coordinator charges
incurred as a result of the relevant Transaction; (v) transmission charges
incurred with regard to such Transaction Quantity; and (vi) any other
out-of-pocket expenses incurred by EMMT in effectuating the relevant
Transaction. Option premia paid to third parties and directly related to the
Transactions shall be charged to MWGen as Reimbursements. Option premia received
from third parties and directly related to the Transactions shall be paid to
MWGen or credited against amounts owing from MWGen to EMMT.

        (c)   MWGen shall pay for any generation, dispatch, and/or settlement
management software and consultant services costs reasonably allocable to the
relevant Transactions, provided that, such software and consultant services have
been approved by MWGen.

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        (d)   The unrealized results of all financial Transactions entered into
pursuant to this Agreement shall not be included in the monthly settlement
between MWGen and EMMT.

ARTICLE IV
DEFINITIONS

        In addition to the defined terms set forth in the Agreement, the
following terms shall have the following meanings for purposes of this Energy
Schedule:

        "Buyer" shall have the meaning set forth in Section 2.1.

        "ExGen Transaction(s)" shall have the meaning set forth in Section 1.1.

        "Delivery Point" shall have the meaning set forth in Section 1.2.

        "Force Majeure" shall have the meaning set forth in Section 2.5.

        "Reliability Organizations" shall have the meaning set forth in
Section 1.2.

        "Reimbursements" shall have the meaning set forth in Section 3.1.

        "Seller" shall have the meaning set forth in Section 2.1.

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        IN WITNESS WHEREOF, the Parties hereto have caused this Energy Schedule
to be duly executed and delivered by their proper and duly authorized officers
as of the day and year first above written.

    MlDWEST GENERATION, LLC,
a Delaware limited liability company
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President        
 
 
EDISON MISSION MARKETING & TRADING, INC.,
a California corporation
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President        

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SCHEDULE B TO AMENDED AND RESTATED
MASTER PURCHASE, SALE AND SERVICES AGREEMENT (NATURAL GAS
PURCHASE, SALE AND SERVICES SCHEDULE)

        This SCHEDULE B TO AMENDED AND RESTATED MASTER PURCHASE, SALE, AND
SERVICES AGREEMENT (NATURAL GAS PURCHASE, SALE AND SERVICES SCHEDULE) ("Gas
Schedule") is entered into this 27th day of April, 2004 between MIDWEST
GENERATION, LLC, a Delaware limited liability company ("MWGen"), and EDISON
MISSION MARKETING & TRADING, INC., a California corporation ("EMMT"). Each of
MWGen and EMMT may be referred to herein as a "Party" and together shall be
referred to as the "Parties".

        WHEREAS, the Parties entered into an Amended and Restated Master
Purchase, Sale and Services Agreement of even date herewith (the "Agreement"),
which provides that Schedules might be added thereto from time to time setting
forth the terms and conditions upon which the Parties would buy and sell
Products from one another and facilitate each other's entering into Transactions
with third parties;

        WHEREAS, the Parties desire to add this Gas Services Schedule to the
Agreement to provide for the facilitation of the purchase and sale of physical
and financial Gas by MWGen and EMMT and EMMT's arrangement for the
transportation and storage of natural gas for such purchases and sales for
MWGen;

        WHEREAS, the Parties entered into a Base Contract for Short-Term Sale
and Purchase of Natural Gas dated on or about January 7, 2000 (the "GISB"),
which supplements the terms of this Gas Schedule and remains unaffected by this
Gas Services Schedule, and is attached hereto and fully incorporated by
reference herein.

        WHEREAS, all capitalized terms used in this Gas Schedule that are
defined in the Agreement shall have the respective meanings herein given to such
terms in the Agreement;

        NOW THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Parties covenant and agree as follows:

ARTICLE I
SCOPE OF AGREEMENT

        1.1   Scope of Agreement. This Gas Schedule shall govern the Parties'
rights and obligations with respect to the Parties' purchase and sale of Gas
between each other and third parties and the arrangement for transportation and
storage of such Gas. Unless otherwise agreed, EMMT shall purchase and sell Gas
and arrange for Transportation and storage of Gas solely as agent for MWGen. The
GISB shall govern the purchase and sale of Gas between the Parties in physical
Transactions in which each Party is a principal, except as provided herein. The
terms and conditions of the Agreement shall apply to Transactions entered into
pursuant to this Gas Schedule, provided that, in case of any conflict between
the Agreement and this Gas Schedule, this Gas Schedule shall govern. In case of
any conflict between the GISB and this Gas Schedule, this Gas Schedule shall
govern.

        1.2   Transaction Procedures and Information. MWGen shall promptly
deliver to EMMT all material information related to its supply and requirements
for natural gas and other information related to the Facilities, including, but
not limited to, estimated hourly output of the Facilities for Gas usage
projections, which shall be delivered at least two (2) Business Days prior to
such usage, historical data, and any information related to the heat rate(s) of
the Facilities. Any data received by MWGen from ExGen related to Gas usage or
otherwise related to the Facilities shall be promptly delivered to EMMT, and
MWGen shall notify EMMT from time to time of MWGen's Gas requirements as they
become known to MWGen. Such notification (each, a "Requirements Notice") shall
be effectuated and

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evidenced (i) by a written notice executed by MWGen, or (ii) in such other form
as agreed by the Parties in writing. The information to be provided in a
Requirements Notice shall include the type and amount of Gas required, the
desired delivery date and the desired delivery point of such Gas.

        1.3   Services.

        (a)   Subject to the terms, conditions, restrictions and limitations set
forth herein, the Parties agree that EMMT will perform all services reasonably
necessary for the performance and satisfaction of all of EMMT's obligations
hereunder, including, without limitation:

        (i)    Developing Gas procurement strategy in conjunction with MWGen to
support the Risk Management Guidelines;

        (ii)   Identifying sources of Gas for the Facilities and proposing
strategies for the purchasing (either from third party sellers or from EMMT
itself), Transportation and storage of Gas for the Facilities, including but not
limited to the term of different supply contracts;

        (iii)  Negotiating for approval and execution by MWGen (or EMMT as agent
for MWGen in Disclosed Agent Transactions) and administering all contracts or
arrangements necessary for MWGen to purchase Gas;

        (iv)  Negotiating for approval and execution by MWGen and administering
all of MWGen's contracts or arrangements necessary for the Transportation of Gas
to the Facilities;

        (v)   Developing procedures for the receipt of the Gas delivered to the
Facilities;

        (vi)  Reviewing and recommending approval (for final approval and
execution by MWGen) for payment by MWGen to providers of goods and services in
connection with MWGen's contracts or arrangements administered by EMMT pursuant
to clauses (i) through (iv) above;

        (vii) Maintaining records with respect to the identification, purchase,
scheduling, Transportation, delivery and storage of Gas pursuant hereto;

        (viii) Performing any other acts necessary to support the
identification, purchase, scheduling, Transportation, delivery and storage of
Gas in accordance with this Schedule;

        (ix)  Providing MWGen on a monthly basis fuel cost projections to be
incorporated into MWGen's Operating Budget for the current calendar year and the
subsequent two years as well as EMMT's projected costs for managing the Gas
supply in accordance with the terms of this Schedule;

        (x)   Identifying purchasers of excess Gas (which may be either third
party purchases or EMMT itself) and developing strategies for the sale of excess
Gas (if any);

        (xi)  Negotiating for approval and execution by MWGen and administering,
as appropriate, contracts or arrangements for MWGen to sell excess Gas;

        (xii) Reviewing and recommending approval (for final approval and
execution by MWGen) for payment and issuance of invoices by MWGen to purchasers
of excess Gas in connection with MWGen's contracts or arrangements administered
by EMMT pursuant to clause (xi) above;

        (xiii) Maintaining records with respect to the sale of excess Gas
pursuant hereto; and

        (xiv) Performing any other acts necessary to support the sale of excess
Gas in accordance with this Schedule.

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        (b)   Subject to the terms and conditions of this Schedule, EMMT shall
recommend to MWGen and the Parties shall jointly develop the means, methods and
procedures (i) with respect to the purchase, Transportation, delivery and
storage of Gas pursuant hereto and (ii) as appropriate, with respect to the sale
and disposal of excess Gas pursuant hereto.

        (c)   EMMT hereby covenants and agrees that in the performance of its
obligations hereunder (i) it shall negotiate to obtain the requisite Gas at
commercially reasonable prices and on commercially reasonable terms; (ii) it
shall negotiate to sell or otherwise dispose of any excess Gas at commercially
reasonable prices and on commercially reasonable terms and conditions; and
(iii) the services provided by EMMT to MWGen shall be performed: (A) in
accordance with Prudent Industry Practice and in compliance with all applicable
laws and regulations, and (B) in accordance with the Risk Management Guidelines
and any other applicable requirements of this Schedule.

ARTICLE II
OBLIGATIONS OF THE PARTIES

        2.1   Failure to Deliver or Receive Transaction Quantity.

        (a)   In Disclosed Agent Transactions, MWGen shall reimburse EMMT for
any charges, penalties or damages EMMT incurs as a result of MWGen's failure to
deliver to or receive from such third parties the Transaction Quantity.

        (b)   In Transactions other than Disclosed Agent Transactions, unless
excused by Force Majeure or Buyer's failure to receive Gas, if Seller fails to
deliver all or part of the Transaction Quantity,, Seller shall pay Buyer, for
each part of the Transaction Quantity not delivered, an amount determined
pursuant to the terms of the GISB plus two cents ($0.02) for each MMBTU replaced
by Buyer.

        (c)   Payments pursuant to this Section 2.1 shall be due and payable by
Seller according to the payment terms in Section 3.1 of the Agreement.

ARTICLE III
PRICING AND PAYMENT

        3.1   Price and Reimbursement.

        (a)   For sales by MWGen to EMMT, EMMT shall pay MWGen the Transaction
Price for the Transaction Quantity less the Reimbursements (as defined herein).
For sales by EMMT to MWGen, MWGen shall pay EMMT the Transaction Price for the
Transaction Quantity plus the Reimbursements. In the case of Disclosed Agent
Transactions, MWGen shall pay EMMT an agency fee equal to the Reimbursements for
such Transaction Quantity.

        (b)   With respect to any Transaction Quantity, the term
"Reimbursements" shall mean (i) $0.02 for each MMBtu of the Transaction
Quantity; (ii) broker fees incurred with regard to such Transaction Quantity;
(iii) any local, state or federal governmental or other regulatory charges
and/or taxes incurred with respect to such Transaction Quantity; and (iv) any
other direct out-of-pocket expenses incurred by EMMT in effectuating the
relevant Transaction. Option premia paid to third parties and directly related
to the Transactions shall be charged to MWGen as Reimbursements. Option premia
received from third parties and directly related to the Transactions shall be
paid to MWGen or credited against amounts owing from MWGen to EMMT.

        (c)   MWGen shall pay for any software and consultant services costs
reasonably allocable to the relevant Transactions, provided that such software
and consultant services are approved by MWGen.

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        (d)   The unrealized results of all financial Transactions entered into
pursuant to this Agreement shall not be included in the monthly settlement
between MWGen and EMMT.

ARTICLE IV
DEFINITIONS

        "Gas" shall mean any mixture of hydrocarbons and non-combustible gases
in a gaseous state consisting primarily of methane.

        "GISB" shall have the meaning set forth in the Fourth Recital to this
Agreement.

        "Reimbursements" shall have the meaning set forth in Section 3.1(b).

        "Transportation" shall mean movement of Gas via pipeline from origins to
the Facilities.

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        IN WITNESS WHEREOF, the Parties hereto have caused this Gas Schedule to
be duly executed and delivered by their proper and duly authorized officers as
of the day and year first above written.

    MlDWEST GENERATION, LLC,
a Delaware limited liability company
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President        
 
 
EDISON MISSION MARKETING & TRADING, INC.,
a California corporation
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President        

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SCHEDULE C TO AMENDED AND RESTATED
MASTER PURCHASE, SALE AND SERVICES AGREEMENT
(FUEL OIL PURCHASE AND SALE SCHEDULE)

        This SCHEDULE C TO AMENDED AND RESTATED MASTER PURCHASE, SALE, AND
SERVICES AGREEMENT (FUEL OIL PURCHASE AND SALE SCHEDULE) ("Fuel Oil Schedule")
is entered into this 27th day of April, 2004 between MIDWEST GENERATION, LLC, a
Delaware limited liability company ("MWGen"), and EDISON MISSION MARKETING &
TRADING, INC., a California corporation ("EMMT"). Each of MWGen and EMMT may be
referred to herein as a "Party" and together shall be referred to as the
"Parties".

        WHEREAS, the Parties entered into an Amended and Restated Master
Purchase, Sale and Services Agreement of even date herewith (the "Agreement"),
which provides that Schedules might be added thereto from time to time setting
forth the terms and conditions upon which the Parties would buy and sell
Products from one another and facilitate each other's entering into Transactions
with third parties;

        WHEREAS, the Parties desire to add this Fuel Oil Schedule to the
Agreement so that EMMT may hedge the market risk for the supply of Fuel Oil to
MWGen's Facilities ("Fuel Oil Transactions");

        WHEREAS, all capitalized terms used in this Fuel Oil Schedule that are
defined in the Agreement shall have the respective meanings herein given to such
terms in the Agreement;

        NOW, THEREFORE, in consideration of the foregoing, and for other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Parties covenant and agree as follows:

ARTICLE 1
SCOPE OF AGREEMENT

        1.1.  Scope of Agreement. The terms and conditions of the Agreement
shall apply to Transactions entered into pursuant to this Fuel Oil Schedule,
provided that, in case of any conflict between the Agreement and this Fuel Oil
Schedule, this Fuel Oil Schedule shall govern.

        1.2.  Transaction Procedures and Information. MWGen shall notify EMMT
from time to time of MWGen's fuel oil requirements and MWGen's fuel oil
contracts and commitments as they become known to MWGen. Such notification
(each, a "Requirements Notice") shall be effectuated and evidenced (i) by a
written notice executed by MWGen, or (ii) in such other form as agreed by the
Parties in writing. The information to be provided in a Requirements Notice
shall include the type and amount of Fuel Oil required or contracted for, the
Delivery Point, the Transaction Price in the case of Fuel Oil contracts and
commitments, and the desired delivery date of such Fuel Oil.

        1.3.  Term. This Fuel Oil Schedule shall commence on the date hereof
(the "Schedule Effective Date") and shall remain in effect until terminated by
either Party upon thirty (30) days prior written notice, or as the Parties
mutually agree in writing; provided, however, that this Fuel Oil Schedule shall
remain in effect with respect to any Transaction(s) entered into prior to the
effective date of the termination until both Parties have fulfilled their
obligations with respect to such Transaction(s).

ARTICLE II
OBLIGATIONS OF THE PARTIES; TITLE

        2.1   Responsibilities of EMMT. EMMT hereby covenants and agrees that in
the performance of its obligations hereunder it shall use commercially
reasonable care in developing and executing Transactions hereunder so as to
comply with the Risk Management Guidelines.

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        2.2.  Third Party Non-Performance. If EMMT does not receive payment from
the third party buyer or third party seller by two (2) Business Days prior to
the payment date in the Agreement, EMMT shall make such payment to MWGen two
(2) Business Days after receipt of payment from such third party buyer or seller
(as the case may be).

ARTICLE III
PRICING AND PAYMENT

        3.1   Price and Reimbursement.

        (a)   For sales by MWGen to EMMT, EMMT shall pay MWGen the Transaction
Price for the Transaction Quantity less the Reimbursements (as defined herein).
For sales by EMMT to MWGen, MWGen shall pay EMMT the Transaction Price for the
Transaction Quantity plus the Reimbursements.

        (b)   With respect to any Transaction Quantity, the term
"Reimbursements" shall mean (i) $0.05 per barrel of the Transaction Quantity
(ii) broker fees incurred with regard to such Transaction Quantity; (iii) any
local, state or federal governmental or other regulatory charges and/or taxes
incurred with respect to such Transaction Quantity; (iv) any other direct
out-of-pocket expenses incurred by EMMT in effectuating the relevant
Transaction. Option premia paid to third parties and directly related to the
Transactions shall be charged to MWGen as Reimbursements. Option premia received
from third parties and directly related to the Transactions shall be paid to
MWGen or credited against amounts owing from MWGen to EMMT.

        (c)   The unrealized results of all financial Transactions entered into
pursuant to this Agreement shall not be included in the monthly settlement
between MWGen and EMMT.

ARTICLE IV
DEFINITIONS

        In addition to the defined terms set forth in the Agreement, the
following terms shall have the following meanings for purposes of this Fuel Oil
Schedule:

        "Buyer" shall have the meaning set forth in Section 2.1.

        "Fuel Oil" shall mean any types of heating, fuel or crude oil, or
derivatives thereof, including, but not limited to, No. 2 Heating Oil and No. 6
Fuel Oil.

        "Reimbursements" shall have the meaning set forth in Section 3.1.

        "Schedule Effective Date" shall have the meaning set forth in
Section 1.3.

        "Seller" shall have the meaning set forth in Section 2.1.

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        IN WITNESS WHEREOF, the Parties hereto have caused this Fuel Oil
Schedule to be duly executed and delivered by their proper and duly authorized
officers as of the day and year first above written.

    MlDWEST GENERATION, LLC,
a Delaware limited liability company     By: /s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President             EDISON MISSION MARKETING & TRADING, INC.,
a California corporation
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President        

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SCHEDULE D TO AMENDED AND RESTATED
MASTER PURCHASE, SALE AND SERVICES AGREEMENT
(EMISSION ALLOWANCE PURCHASE AND SALE SCHEDULE)

        This SCHEDULE D TO AMENDED AND RESTATED MASTER PURCHASE, SALE, AND
SERVICES AGREEMENT (EMISSION ALLOWANCE PURCHASE AND SALE SCHEDULE) ("Emission
Allowance Schedule") is entered into this 27th day of April, 2004 between
MIDWEST GENERATION, LLC, a Delaware limited liability company ("MWGen"), and
EDISON MISSION MARKETING & TRADING, INC., a California corporation ("EMMT").
Each of MWGen and EMMT may be referred to herein as a "Party" and together shall
be referred to as the "Parties".

        WHEREAS, the Parties entered into an Amended and Restated Master
Purchase, Sale and Services Agreement of even date herewith (the "Agreement"),
which provides that Schedules might be added thereto from time to time setting
forth the terms and conditions upon which the Parties would buy and sell
Products from one another and facilitate each other's entering into Transactions
with third parties;

        WHEREAS, the Parties desire to add this Emission Allowance Schedule to
the Agreement to provide for the purchase and sale of physical and financial
Emission Allowances from MWGen to EMMT;

        WHEREAS, all capitalized terms used in this Emission Allowance Schedule
that are defined in the Agreement shall have the respective meanings herein
given to such terms in the Agreement;

        NOW THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Parties covenant and agree as follows:

ARTICLE I
SCOPE OF AGREEMENT

        1.1   Scope of Agreement.

        (a)   This Emission Allowance Schedule shall govern the Parties' rights
and obligations with respect to the Parties' purchase and sale of emission
allowances, including, but not limited to, Allowances for nitrogen oxide ("NOx")
and sulfur dioxide ("SO2") (collectively, the "Emission Allowances"). The terms
and conditions of the Agreement shall apply to Transactions entered into
pursuant to this Emission Allowance Schedule, provided that, in case of any
conflict between the Agreement and this Emission Allowance Schedule, this
Emission Allowance Schedule shall govern.

        (b)   EMMT may also enter into financial hedge transactions related to
the emissions from the Facilities from time to time.

        (c)   All Transactions described in subsections (a) and (b) above
(collectively, "Emission Allowance Transactions") shall be entered into by EMMT
and MWGen according to the guidelines established and amended from time to time
(the "Risk Management Guidelines") by the EMMT Risk Management Committee, which
is comprised of senior officers and representatives of both EMMT and MWGen. EMMT
shall be required to use commercially reasonable care in developing and
executing Emission Allowance Transactions so as to comply with the Risk
Management Guidelines. EMMT shall advise MWGen on marketing and other business
strategies from time to time.

        1.2   Transaction Procedures and Information.

        (a)   MWGen shall promptly deliver all material information related to
its Emission Allowances and Emission Allowance requirements to EMMT. MWGen shall
further notify EMMT

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of any regulatory or third party actions that could reasonably affect such
Emission Allowances or Emission Allowance requirements.

        (b)   The transaction price ("Transaction Price"), quantity
("Transaction Quantity"), the date on which the seller of the Emission Allowance
must submit the Allowance Transfer Form to the EPA ("Delivery Date"), type of
Emission Allowance, Vintage Year, of Emission Allowances purchased or sold by
EMMT and MWGen under this Agreement, and the terms and conditions of any
financial transaction entered into under this Agreement, shall be established in
a Back-to-Back Transaction between EMMT and an unrelated third party (except for
Disclosed Agent Transactions). Each Emission Allowance Transaction hereunder
shall be designated by EMMT as a "hedge transaction" in EMMT's Energy Trading
System or other applicable software at or before the execution of its
corresponding Back-to-Back Transaction (except for Disclosed Agent Transactions,
which shall be designated at the time of such Transaction), and shall be
subsequently evidenced by a written notice (a "Transaction Notice") from EMMT
that includes reasonable detail of such Transaction, including the Transaction
Price, Transaction Quantity, and Delivery Date. Such Transaction Notice may be
provided (i) in a monthly accounting journal entry; or (ii) in such other form
as agreed by the Parties in writing.

ARTICLE II
OBLIGATIONS OF THE PARTIES

        2.1   Transfer Procedures. The Parties shall develop procedures for
coordinating the transfer of Emission Allowances pursuant to this Emission
Allowance Schedule.

        2.2   Failure to Deliver.

        (a)   In Disclosed Agent Transactions, MWGen shall reimburse EMMT for
any charges, penalties or damages EMMT incurs as a result of MWGen's failure to
deliver the Transaction Quantity to, or receive the Transaction Quantity from,
such third parties.

        (b)   In Transactions other than Disclosed Agent Transactions, unless
excused by the Buyer's failure to receive Emission Allowances, if Seller fails
to deliver all of part of the Transaction Quantity, Seller shall pay Buyer for
each part of the Transaction Quantity not delivered by an amount equal to either
(i) the price at which Buyer, acting in a commercially reasonable manner,
purchases substitute Emission Allowances not delivered by Seller or (ii) absent
a purchase, the market price for such quantity as determined by Buyer in a
commercially reasonable manner,

        (c)   Payments pursuant to Section 2.2 shall be due and payable by
Seller according to the payment terms in Section 3.1 of the Agreement.

ARTICLE III
PRICING AND PAYMENT

        3.1   Price and Reimbursement.

        (a)   For sales by MWGen to EMMT, EMMT shall pay MWGen the Transaction
Price for the Transaction Quantity less the Reimbursements (as defined herein).
For sales by EMMT to MWGen, MWGen shall pay EMMT the Transaction Price for the
Transaction Quantity plus the Reimbursements. In the case of Disclosed Agent
Transactions, MWGen shall pay EMMT an agency fee equal to the Reimbursements for
such Transaction Quantity.

        (b)   With respect to any Transaction Quantity, the term
"Reimbursements" shall mean (i) $0.25 for each SO2 Emission Allowance in the
Transaction Quantity; (ii) $25.00 for each NOx Emission Allowance in the
Transaction Quantity; (iii) broker fees incurred with regard to such Transaction
Quantity; (iv) any governmental or regulatory charges incurred with respect to
such Transaction

D-2

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Quantity; and (v) any other out-of-pocket expenses incurred by EMMT in
effectuating the relevant Transaction. Option premia paid to third parties and
directly related to the Transactions shall be charged to MWGen as
Reimbursements. Option premia received from third parties and directly related
to the Transactions shall be paid to MWGen or credited against amounts owing
from MWGen to EMMT.

        (c)   MWGen shall pay for any software and consultant services costs
reasonably allocable to the relevant Transactions, provided that such software
and consultant services have been approved by MWGen.

        (d)   The unrealized results of all financial transactions entered into
pursuant to this Agreement shall not be included in the monthly settlement
between MWGen and EMMT.

ARTICLE IV
DEFINITIONS

        "Allowance" shall mean the authorization from any state that is a
signatory to or subject to the Ozone Transport Commission Memorandum of
Understanding dated September 27, 1994 to emit one ton of NOx (May through
September) or the authorization by the Administrator of the EPA to emit one ton
of SO2 under Title IV of The Clean Air Act Amendments of 1990, as the same may
be amended) or supplemented, or any successor statutes which are the basis for
The Federal Air Pollution Control Program for Sulfur Dioxide Emissions, in the
Vintage Year of issue or in subsequent control periods (subject to restrictions
on banked allowances).

        "Delivery Date" shall have the meaning set forth in Section 1.2.

        "Emission Allowances" shall have the meaning set forth in Section 1.1.

        "EPA" shall mean the United States Environmental Protection Agency or
its successor.

        "NOx" shall have the meaning set forth in Section 1.1.

        "Reimbursements" shall have the meaning set forth in Section 3.1(b).

        "SO2" shall have the meaning set forth in Section 1.1.

        "Vintage Year" shall mean the first calendar year during which the
Allowances may be utilized.

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        IN WITNESS WHEREOF, the Parties hereto have caused this Emission
Allowance Schedule to be duly executed and delivered by their proper and duly
authorized officers as of the day and year first above written.

    MlDWEST GENERATION, LLC,
a Delaware limited liability company
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President             EDISON MISSION MARKETING & TRADING, INC.,
a California corporation
 
 
By:
/s/  JOHN P. FINNERAN, JR.      

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Name: John P. Finneran, Jr.
Title: Vice President        

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AMENDED AND RESTATED MASTER PURCHASE, SALE AND SERVICES AGREEMENT
ARTICLE VI DEFINITIONS