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                                                                 Exhibit 10.16.4

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             AMENDED AND RESTATED GUARANTEE AND COLLATERAL AGREEMENT


                                     made by


                         EME HOMER CITY GENERATION L.P.




                                   in favor of

                              THE BANK OF NEW YORK
                                 as successor to

                    UNITED STATES TRUST COMPANY OF NEW YORK,
                               as Collateral Agent



                          Dated as of December __, 2001


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                                TABLE OF CONTENTS
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                                                                                                PAGE
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SECTION 1. DEFINED TERMS...........................................................................1
         1.1      Definitions......................................................................1
         1.2      Other Definitional Provisions....................................................3

SECTION 2. PLEDGE; GRANT OF SECURITY INTEREST......................................................3

SECTION 3. REPRESENTATIONS AND WARRANTIES..........................................................3
         3.1      Title; No Other Liens............................................................3
         3.2      Perfected First Priority Liens...................................................3
         3.3      Chief Executive Office...........................................................4

SECTION 4. COVENANTS...............................................................................4
         4.1      Delivery of Instruments, Certificated Securities and Chattel  Paper..............4
         4.2      Maintenance of Perfected Security Interest Further Documentation.................4
         4.3      Changes in Locations, Name, etc..................................................4
         4.4      Notices..........................................................................5

SECTION 5. REMEDIAL PROVISIONS.....................................................................5
         5.1      Proceeds to be Turned Over To Collateral Agent...................................5
         5.2      Deposits; Application of Proceeds................................................5
         5.3      Direction of Secured Parties.....................................................6
         5.4      Code and Other Remedies..........................................................6
         5.5      Waiver; Deficiency...............................................................7

SECTION 6. THE COLLATERAL AGENT....................................................................7
         6.1      Collateral Agent's Appointment as Attorney-in-Fact, etc..........................7
         6.2      Duty of Collateral Agent.........................................................8
         6.3      Execution of Financing Statements................................................9
         6.4      Authority of Collateral Agent....................................................9

SECTION 7. MISCELLANEOUS...........................................................................9
         7.1      Amendments in Writing............................................................9
         7.2      Notices..........................................................................9
         7.3      No Waiver by Course of Conduct; Cumulative Remedies.............................10
         7.4      Successors and Assigns..........................................................10
         7.5      Set-Off.........................................................................10
         7.6      Counterparts....................................................................11
         7.7      Severability....................................................................11
         7.8      Section Headings................................................................11
         7.9      Integration.....................................................................11
         7.10     GOVERNING LAW...................................................................11
         7.11     Submission To Jurisdiction; Waivers.............................................11
         7.12     Acknowledgements................................................................12
         7.13     Releases........................................................................12


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         7.14     Security Interest Absolute......................................................13
         7.15     WAIVER OF JURY TRIAL............................................................14


SCHEDULES

Schedule 1........Notice Addresses
Schedule 2........Perfection Matters
Schedule 3........Jurisdictions of Organization and Chief Executive Offices
</Table>


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           AMENDED AND RESTATED GUARANTEE AND COLLATERAL AGREEMENT, dated as of
December __, 2001, made by EME HOMER CITY GENERATION L.P., a Pennsylvania
limited partnership ("THE PLEDGOR") in favor of THE BANK OF NEW YORK, as
successor to UNITED STATES TRUST COMPANY OF NEW YORK, as collateral agent for
the Secured Parties (as defined below) (in such capacity, the "COLLATERAL
AGENT").

                                    RECITALS

           A.    Contemporaneously herewith, the Pledgor will enter into a
transaction pursuant to the Participation Agreements listed on Schedule 1 (as
amended, modified and supplemented and in effect from time to time, each
"PARTICIPATION AGREEMENT") whereby the Pledgor will sell certain of its
generating assets to the Owner Lessor and the Owner Lessor will lease such
generating assets to the Pledgor under the Facility Lease.

           B.    In consideration of the transactions contemplated by each of
the Participation Agreements, the Pledgor will be obligated to pay to the
Secured Parties the aggregate amount of all obligations owed by the Pledgor to
the Secured Parties under each Participation Agreement and the other Operative
Documents related thereto (the "LEVERAGED LEASE OBLIGATIONS").

           C.    In satisfaction of the requirements of the Secured Parties,
the Pledgor desires by this Agreement and the other Security Documents (as
defined below) to provide collateral as security for its obligations under each
Participation Agreement and the other Operative Documents related thereto

           D.    In order to simplify administration of such collateral and to
provide for the orderly enforcement of their respective rights, the Secured
Parties (as defined below) have appointed the Collateral Agent to serve as
their common representative, to be the beneficiary under any pledge intended to
benefit the Secured Parties, and to hold the liens created, or to be created,
under all Operative Documents.

           E.    It is a condition precedent to the approval by the Secured
Parties of the transactions contemplated by the Operative Documents that the
Pledgor shall have executed and delivered this Agreement to the Collateral
Agent for the benefit of the Secured Parties.

           NOW, THEREFORE, in consideration of the premises, the Pledgor hereby
agrees with the Collateral Agent, for the benefit of the Secured Parties, as
follows:

                            SECTION 1. DEFINED TERMS

           1.1    DEFINITIONS. (a) Unless otherwise defined herein, terms
defined in the Participation Agreement and used herein shall have the meanings
given to them in each Participation Agreement.

           (b)   The following terms shall have the following meanings:

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           "AGREEMENT": this Amended and Restated Guarantee and Collateral
Agreement, as the same may be amended, supplemented or otherwise modified from
time to time.

           "CERTIFICATED SECURITY": the collective reference to (i) any
"certificated security" as defined in Section 8-102(a)(4) of the New York UCC
and (ii) all limited liability company certificates, partnership interest
certificates and certificated options therefor that may be issued or granted by
any issuer.

           "COLLATERAL": as defined in SECTION 2.

           "COLLATERAL ACCOUNT": any collateral account established by the
Collateral Agent as provided in SECTION 5.1.

           "FACILITY LEASE": as defined in each Participation Agreement.

           "GENERAL INTANGIBLES": all "general intangibles" as such term is
defined in Section 9-106(a)(42) of the New York UCC excluding with respect to
the Pledgor, all emissions allowances and credits and all contracts,
agreements, instruments and indentures in any form, and portions thereof, to
which the Pledgor is a party or under which the Pledgor has any right, title or
interest or to which the Pledgor or any property of the Pledgor is subject, as
the same may from time to time be amended, supplemented or otherwise modified.

           "LEASE EVENT OF DEFAULT": as defined in each Participation Agreement.

           "LEASE INDENTURE TRUSTEE": as defined in each Participation
Agreement.

           "LEASE SUBORDINATION AGREEMENT": the Lease Subordination Agreement,
dated as of December __, 2001, among the Owner Lessors, the Owner Participant
and the Lease Indenture Trustee.

           "NEW YORK UCC": the Uniform Commercial Code as from time to time in
effect in the State of New York.

           "PERSON": any natural person, corporation, partnership, limited
liability company, firm, association, trust, government, governmental agency or
other entity, whether acting in an individual, fiduciary or other capacity.

           "PLEDGOR": as defined in the PREAMBLE.

           "PROCEEDS": all "proceeds" as such term is defined in Section
9-102(a)(64) of the New York UCC.

           "SECURED PARTIES": the Collateral Agent, the Owner Lessors and the
Owner Participant.

           "SECURITIES ACT": the Securities Act of 1933, as amended.


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           1.2   OTHER DEFINITIONAL PROVISIONS. (a) The words "hereof",
"herein" and "hereunder" and words of similar import when used in this
Agreement shall refer to this Agreement as a whole and not to any particular
provision of this Agreement, and section, schedule, appendix and exhibit
references are to this Agreement unless otherwise specified.

           (b)   Each reference in this Agreement to a Operative Document or
other agreement shall be deemed to refer to such Operative Document or other
agreement as the same may be amended, supplemented or otherwise modified from
time to time.

           (c)   Any term defined by reference to an agreement, instrument or
other document shall have the meaning so assigned to it whether or not such
agreement, instrument or document is in effect.

           (d)   Each reference in this Agreement to a Person shall be deemed
to include such Person's successors and assigns.

           (e)   Each reference in this Agreement to a Requirement of Law shall
be deemed to refer to such Requirement of Law as the same may be amended,
supplemented or otherwise modified from time to time.

           (f)   The meanings given to terms defined herein shall be equally
applicable to both the singular and plural forms of such terms.

                 SECTION 2. PLEDGE; GRANT OF SECURITY INTEREST

           The Pledgor hereby pledges and grants to the Collateral Agent, for
the benefit of the Secured Parties, a security interest in all of the General
Intangibles now owned or at any time hereafter acquired by the Pledgor or in
which the Pledgor now has or at any time in the future may acquire any right,
title or interesttogether with all Proceeds thereof (collectively, the
"COLLATERAL"), as collateral security for the prompt and complete payment and
performance when due (whether at the stated maturity, by acceleration or
otherwise) of the Leveraged Lease Obligations.

                   SECTION 3. REPRESENTATIONS AND WARRANTIES

           The Pledgor hereby represents and warrants, with respect to itself
and its Collateral, to the Collateral Agent and each Secured Party that:

           3.1   TITLE; NO OTHER LIENS. Except for the security interest
granted to the Collateral Agent pursuant to this Agreement, the Pledgor owns
each item of the Collateral free and clear of any and all Liens or claims of
others. No financing statement or other public notice with respect to all or
any part of the Collateral is on file or of record in any public office, except
such as have been filed in favor of the Collateral Agent pursuant to this
Agreement or as are permitted by the Operative Documents.

           3.2   PERFECTED FIRST PRIORITY LIENS. The security interests granted
pursuant to this Agreement upon completion of the filings and other actions
specified on SCHEDULE 2 (which, in the case of all filings and other documents
referred to on said SCHEDULE, have been delivered to


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the Collateral Agent in completed and duly executed form) will (a) constitute
valid and enforceable perfected security interests in all of the Collateral in
favor of the Collateral Agent as collateral security for the Leveraged Lease
Obligations to the extent that a security interest may be perfected by filing
and/or the other actions specified on SCHEDULE 2, and (b) are prior to all
other Liens on the Collateral in existence on the date hereof except for Liens
permitted by the Operative Documents and which have priority over the Liens on
the Collateral by operation of law.

           3.3   CHIEF EXECUTIVE OFFICE. On the date hereof, the Pledgor's
jurisdiction of organization and the location of the Pledgor's chief executive
office or sole place of business are specified on SCHEDULE 3.

                              SECTION 4. COVENANTS

           The Pledgor covenants and agrees with the Collateral Agent and the
Secured Parties that, from and after the date of this Agreement until the
Leveraged Lease Obligations shall have been paid in full:

           4.1   DELIVERY OF INSTRUMENTS, CERTIFICATED SECURITIES AND CHATTEL
PAPER. If any amount payable under or in connection with any of the Collateral
shall be or become evidenced by any Instrument, Certificated Security or
Chattel Paper, such Instrument, Certificated Security or Chattel Paper shall be
immediately delivered to the Collateral Agent, duly indorsed in a manner
satisfactory to the Collateral Agent, to be held as Collateral pursuant to this
Agreement.

           4.2   MAINTENANCE OF PERFECTED SECURITY INTEREST FURTHER
DOCUMENTATION. (a) The Pledgor shall take any and all actions that may be
necessary or, in the reasonable discretion of the Collateral Agent, prudent to
maintain the security interest created by this Agreement as a perfected
security interest having at least the priority described in SECTION 3.2 and
shall defend such security interest against the claims and demands of all
Persons whomsoever.

           (b)   The Pledgor will furnish to the Collateral Agent and the
Secured Parties from time to time statements and schedules further identifying
and describing the Collateral and such other reports in connection therewith as
the Collateral Agent may reasonably request, all in reasonable detail.

           (c)   At any time and from time to time, upon the written request of
the Collateral Agent, and at the sole expense of the Pledgor, the Pledgor will
promptly and duly execute and deliver, and have recorded, such further
instruments and documents and take such further actions as the Collateral Agent
may reasonably request for the purpose of obtaining or preserving the full
benefits of this Agreement and of the rights and powers herein granted,
including (i) filing any financing or continuation statements under the Uniform
Commercial Code (or other similar laws) in effect in any jurisdiction with
respect to the security interests created hereby and (ii) taking any actions
necessary to enable the Collateral Agent to obtain "control" (within the
meaning of the applicable Uniform Commercial Code) with respect thereto.

           4.3   CHANGES IN LOCATIONS, NAME, ETC. The Pledgor will not, except
upon 30 days' prior written notice to the Collateral Agent and delivery to the
Collateral Agent of all additional executed financing statements and other
documents reasonably requested by the


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Collateral Agent to maintain the validity, perfection and priority of the
security interests provided for herein:

                       (i)    change its jurisdiction of organization or the
      location of its chief executive office or sole place of business from that
      referred to in SECTION 3.3; or

                       (ii)   change its name, identity or corporate structure
      to such an extent that any financing statement flied by the Collateral
      Agent in connection with this Agreement would become misleading.

           4.4   NOTICES. The Pledgor will advise the Collateral Agent
promptly, in reasonable detail, of:

           (a)   any Lien (other than security interests created hereby or
Liens permitted under the Operative Documents) on any of the Collateral which
could reasonably be expected to have a material adverse effect on the ability
of the Collateral Agent to exercise any of its remedies hereunder; and

           (b)   of the occurrence of any other event which could reasonably be
expected to have a material adverse effect on the aggregate value of the
Collateral or on the security interests created hereby.

                         SECTION 5. REMEDIAL PROVISIONS

           5.1   PROCEEDS TO BE TURNED OVER TO COLLATERAL AGENT. If a Lease
Event of Default shall occur and be continuing, all Proceeds received by the
Pledgor consisting of cash, checks and other near-cash items shall be held by
the Pledgor in trust for the Collateral Agent, segregated from other funds of
the Pledgor, and shall, forthwith upon receipt by the Pledgor, be turned over
to the Collateral Agent in the exact form received by the Pledgor (duly
indorsed by the Pledgor to the Collateral Agent, if required). All Proceeds
received by the Collateral Agent hereunder shall be held by the Collateral
Agent in a Collateral Account maintained under its sole dominion and control.
All Proceeds while held by the Collateral Agent in a Collateral Account (or by
the Pledgor in trust for the Collateral Agent and the Secured Parties) shall
continue to be held as collateral security for all the Leveraged Lease
Obligations and shall not constitute payment thereof until applied as provided
in SECTION 5.2.

           5.2   DEPOSITS; APPLICATION OF PROCEEDS. Upon the creation of any
Collateral Account, the Collateral Agent shall also establish 8 subaccounts of
such Collateral Account, one subaccount with respect to each Facility Lease and
the other Operative Documents related thereto. All deposits into the Collateral
Account shall be credited to each subaccount based upon such Owner Lessor's
Percentage of such deposited amount. If a Lease Event of Default shall have
occurred and be continuing, at any time thereafter at the Collateral Agent's
election, the Collateral Agent may apply all or any part of Proceeds held in
the applicable subaccount of any Collateral Account in payment of the Leveraged
Lease Obligations in accordance with the applicable Participation Agreement and
the other applicable Operative Documents, and any part of such funds which the
Collateral Agent elects not so to apply and deems not required as collateral
security for any Leveraged Lease Obligations shall be paid over from time to
time by


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the Collateral Agent to the Pledgor or to whomsoever may be lawfully entitled
to receive the same. Any balance of such Proceeds in a subaccount remaining
after applicable Leveraged Lease Obligations shall have been paid in full shall
be paid over to the Pledgor or to whomsoever may be lawfully entitled to
receive the same. It is acknowledged and agreed that sums on deposit in any
subaccount of the Collateral Account shall be held for the benefit of the
applicable Owner Lessor (as collateral for the Leveraged Lease Obligations
under the applicable Facility Lease and the applicable Operative Documents and
shall not constitute collateral for, and shall not be applied to the repayment
of, any obligations of the Facility Lessee owing to any other Owner Lessor
under any other Facility Lease (or other applicable Operative Documents).

           5.3   DIRECTION OF SECURED PARTIES. As provided in the Ownership and
Operating Agreement, which is assigned to each Bondholder Trustee, the Majority
in Interest of Owner Lessors shall be entitled to give and refrain from giving
consents and directions to the Collateral Agent on behalf of all the Secured
Parties (and all Secured Parties shall be bound by such action).

           5.4   CODE AND OTHER REMEDIES. Subject to Article XIV of each
Participation Agreement, if a Lease Event of Default shall occur and be
continuing, the Collateral Agent, on behalf of the Secured Parties, may
exercise, in addition to all other rights and remedies granted to them in this
Agreement and in any other instrument or agreement securing, evidencing or
relating to the applicable Leveraged Lease Obligations, all rights and remedies
of a secured party under the New York UCC or any other applicable law. Without
limiting the generality of the foregoing, the Collateral Agent, without demand
of performance or other demand, presentment, protest, advertisement or notice
of any kind (except any notice required by law referred to below) to or upon
the Pledgor or any other Person (all and each of which demands, defenses,
advertisements and notices are hereby waived), may in such circumstances
forthwith collect, receive, appropriate and realize upon the Collateral, or any
part thereof, and/or may forthwith sell, lease, assign, give option or options
to purchase, or otherwise dispose of and deliver the Collateral or any part
thereof (or contract to do any of the foregoing), in one or more parcels at
public or private sale or sales, at any exchange, broker's board or office of
the Collateral Agent or any Secured Party or elsewhere upon such terms and
conditions as it may deem advisable and at such prices as it may deem best, for
cash or on credit or for future delivery without assumption of any credit risk.
The Collateral Agent or any Secured Party shall have the right upon any such
public sale or sales, and, to the extent permitted by law, upon any such
private sale or sales, to purchase the whole or any part of the Collateral so
sold, free of any right or equity of redemption in the Pledgor, which right or
equity is hereby waived and released. The Pledgor further agrees, at the
Collateral Agent's request, to assemble the Collateral and make it available to
the Collateral Agent at places which the Collateral Agent shall reasonably
select, whether at the Pledgor's premises or elsewhere. The Collateral Agent
shall apply the net proceeds of any action taken by it pursuant to this SECTION
5.3, after deducting all reasonable costs and expenses of every kind incurred
in connection therewith or incidental to the care or safekeeping of any of the
Collateral or in any way relating to the Collateral or the rights of the
Collateral Agent and the Secured Parties hereunder, including, without
limitation, reasonable attorneys' fees and disbursements, to the payment in
whole or in part of the Leveraged Lease Obligations, in such order as the
Collateral Agent may elect, and only after such application and after the
payment by the Collateral Agent of any other amount required by any provision
of law, including, without limitation, Section 9-615(a)(3) of the New York UCC,
need the Collateral Agent account for the


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surplus, if any, to the Pledgor. To the extent permitted by applicable law, the
Pledgor waives all claims, damages and demands it may acquire against the
Collateral Agent or any Secured Party arising out of the exercise by them of
any rights hereunder. If any notice of a proposed sale or other disposition of
Collateral shall be required by law, such notice shall be deemed reasonable and
proper if given at least 10 days before such sale or other disposition.

           5.5   WAIVER; DEFICIENCY. The Pledgor waives and agrees not to
assert any rights or privileges which it may acquire under [Section 9-112] of
the New York UCC.

                        SECTION 6. THE COLLATERAL AGENT

           6.1   COLLATERAL AGENT'S APPOINTMENT AS ATTORNEY-IN-FACT, ETC. (a)
The Pledgor hereby irrevocably constitutes and appoints the Collateral Agent
and any officer or agent thereof, with full power of substitution, as its true
and lawful attorney-in-fact with full irrevocable power and authority in the
place and stead of the Pledgor and in the name of the Pledgor or in its own
name, for the purpose of carrying out the terms of this Agreement, to take any
and all appropriate action and to execute any and all documents and instruments
which may be necessary or desirable to accomplish the purposes of this
Agreement, and, without limiting the generality of the foregoing, the Pledgor
hereby gives the Collateral Agent the power and right, on behalf of the
Pledgor, without notice to or assent by the Pledgor, to do any or all of the
following:

                       (i)    in the name of the Pledgor or its own name, or
      otherwise, take possession of and indorse and collect any checks, drafts,
      notes, acceptances or other instruments for the payment of moneys due
      under any Collateral and file any claim or take any other action or
      proceeding in any court of law or equity or otherwise deemed appropriate
      by the Collateral Agent for the purpose of collecting any and all such
      moneys due under any Collateral whenever payable;

                       (ii)   pay or discharge taxes and Liens levied or placed
      on or threatened against the Collateral, effect any repairs or any
      insurance called for by the terms of this Agreement and pay all or any
      part of the premiums therefor and the costs thereof,

                       (iii)  execute, in connection with any sale provided for
      in SECTION 5.3 or 5.4, any indorsements, assignments or other instruments
      of conveyance or transfer with respect to the Collateral; and

                       (iv)   (1) direct any party liable for any payment under
      any of the Collateral to make payment of any and all moneys due or to
      become due thereunder directly to the Collateral Agent or as the
      Collateral Agent shall direct; (2) ask or demand for, collect, and
      receive payment of and receipt for, any and all moneys, claims and other
      amounts due or to become due at any time in respect of or arising out of
      any Collateral; (3) sign and indorse any invoices, freight or express
      bills, bills of lading, storage or warehouse receipts, drafts against
      debtors, assignments, verifications, notices and other documents in
      connection with any of the Collateral; (4) commence and prosecute any
      suits, actions or proceedings at


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      law or in equity in any court of competent jurisdiction to collect the
      Collateral or any portion thereof and to enforce any other right in
      respect of any Collateral; (5) defend any suit, action or proceeding
      brought against the Pledgor with respect to any Collateral; (6) settle,
      compromise or adjust any such suit, action or proceeding and, in
      connection therewith, give such discharges or releases as the Collateral
      Agent may deem appropriate; and (7) generally, sell, transfer, pledge and
      make any agreement with respect to or otherwise deal with any of the
      Collateral as fully and completely as though the Collateral Agent were
      the absolute owner thereof for all purposes, and do, at the Collateral
      Agent's option and the Pledgor's expense, at any time, or from time to
      time, all acts and things which the Collateral Agent deems necessary to
      protect, preserve or realize upon the Collateral and the Collateral
      Agent's and the Secured Parties' security interests therein and to effect
      the intent of this Agreement, all as fully and effectively as the Pledgor
      might do.

           Anything in this SECTION 6.1(a) to the contrary notwithstanding, the
Collateral Agent agrees that it will not exercise any rights under the power of
attorney provided for in this SECTION 6.1(a) unless a Lease Event of Default
shall have occurred and be continuing.

           (b)   If a Lease Event of Default shall have occurred and be
continuing, if the Pledgor fails to perform or comply with any of its
agreements contained herein, the Collateral Agent, at its option, but without
any obligation so to do, may perform or comply, or otherwise cause performance
or compliance, with such agreement.

           (c)   The expenses of the Collateral Agent incurred in connection
with actions undertaken as provided in this SECTION 6.1, together with interest
thereon at a rate per annum equal to the highest rate per annum at which
interest would then be payable on any category of past due Leveraged Lease
Obligations under the Participation Agreement and the other Operative
Documents, from the date of payment by the Collateral Agent to the date
reimbursed by the Pledgor, shall be payable by the Pledgor to the Collateral
Agent on demand.

           (d)   The Pledgor hereby ratifies all that said attorneys shall
lawfully do or cause to be done by virtue hereof. All powers, authorizations
and agencies contained in this Agreement are coupled with an interest and are
irrevocable until this Agreement is terminated and the security interests
created hereby are released.

           6.2   DUTY OF COLLATERAL AGENT. The Collateral Agent's sole duty
with respect to the custody, safekeeping and physical preservation of the
Collateral in its possession, under Section 9-207 of the New York UCC or
otherwise, shall be to deal with it with the same degree of care as the
Collateral Agent deals with similar property for its own account. Neither the
Collateral Agent, any Secured Party nor any of their respective officers,
directors, employees or agents shall be liable for failure to demand, collect
or realize upon any of the Collateral or for any delay in doing so or shall be
under any obligation to sell or otherwise dispose of any Collateral upon the
request of the Pledgor or any other Person or to take any other action
whatsoever with regard to the Collateral or any part thereof. The powers
conferred on the Collateral Agent and the Secured Parties hereunder are solely
to protect the Collateral Agents and the Secured Parties' interests in the
Collateral and shall not impose any duty upon the


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Collateral Agent or any Secured Party to exercise any such powers. The
Collateral Agent and the Secured Parties shall be accountable only for amounts
that they actually receive as a result of the exercise of such powers, and
neither they nor any of their officers, directors, employees or agents shall be
responsible to the Pledgor for any act or failure to act hereunder, except for
(i) their own gross negligence or willful misconduct or (ii) breach of their
obligations under this Agreement.

           6.3   EXECUTION OF FINANCING STATEMENTS. Pursuant to Section 9-402
of the New York UCC and any other applicable law, the Pledgor authorizes the
Collateral Agent to file or record financing statements and other filing or
recording documents or instruments with respect to the Collateral without the
signature of the Pledgor in such form and in such offices as the Collateral
Agent determines appropriate to perfect the security interests of the
Collateral Agent under this Agreement. A photographic or other reproduction of
this Agreement shall be sufficient as a financing statement or other filing or
recording document or instrument for filing or recording in any jurisdiction.

           6.4   AUTHORITY OF COLLATERAL AGENT. The Pledgor and each Secured
Party by accepting the benefits of this Agreement acknowledges that the rights
and responsibilities of the Collateral Agent under this Agreement with respect
to any action taken by the Collateral Agent or the exercise or non-exercise by
the Collateral Agent of any option, voting right, request, judgment or other
right or remedy provided for herein or resulting or arising out of this
Agreement shall, as between the Collateral Agent and the Secured Parties, be
governed by the Operative Documents and by such other agreements with respect
thereto as may exist from time to time among them, but, as between the
Collateral Agent and the Pledgor, the Collateral Agent shall be conclusively
presumed to be acting as agent for the Secured Parties with full and valid
authority so to act or refrain from acting, and the Pledgor shall not be under
any obligation, or entitlement, to make any inquiry respecting such authority.

                            SECTION 7. MISCELLANEOUS

           7.1   AMENDMENTS IN WRITING. None of the terms or provisions of this
Agreement may be waived, amended, supplemented or otherwise modified except in
writing and in accordance with the Participation Agreement.

           7.2   NOTICES. All notices and other communications to any party
hereto shall be in writing or by facsimile and addressed, delivered or
transmitted to such party at its address or facsimile number set forth on
Schedule 1 or at such other address or facsimile number as may be designated by
such party in a notice to the other parties.


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           7.3   NO WAIVER BY COURSE OF CONDUCT; CUMULATIVE REMEDIES. Neither
the Collateral Agent nor any Secured Party shall by any act (except by a
written instrument pursuant to SECTION 7.1), delay, indulgence, omission or
otherwise be deemed to have waived any right or remedy hereunder or to have
acquiesced in any Lease Event of Default. No failure to exercise, nor any delay
in exercising, on the part of the Collateral Agent or any Secured Party, any
right, power or privilege hereunder shall operate as a waiver thereof. No
single or partial exercise of any right, power or privilege hereunder shall
preclude any other or further exercise thereof or the exercise of any other
right, power or privilege. A waiver by the Collateral Agent or any Secured
Party of any right or remedy hereunder on any one occasion shall not be
construed as a bar to any right or remedy which the Collateral Agent or such
Secured Party would otherwise have on any future occasion. The rights and
remedies herein provided are cumulative, may be exercised singly or
concurrently and are not exclusive of any other rights or remedies provided by
law.

           7.4   SUCCESSORS AND ASSIGNS. (a) This Agreement shall be binding
upon the successors and assigns of the Pledgor and shall inure to the benefit
of the Collateral Agent and the Secured Parties and their successors and
assigns; PROVIDED that the Pledgor may not assign, transfer or delegate any of
its rights or obligations under this Agreement without the prior written
consent of the Collateral Agent.

           (b)   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). The Facility Lessee 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 the
Facility Lessee 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 Lease Indenture Trustee shall have the right to exercise the rights
of such Owner Lessor under this (other than with respect to Excepted Payments
and the rights to enforce and collect the same) to the extent set forth in and
subject in each case to the exceptions set forth in the applicable Lease
Indenture.

           7.5   SET-OFF. The Pledgor hereby irrevocably authorizes the
Collateral Agent and each Secured Party at any time and from time to time (i)
upon the occurrence of a Lease Event of Default of the kind described in
clauses (a), (b), (g) and (h) of Article XVI of the Facility Lease or (ii) upon
the occurrence and continuance beyond the applicable grace period, if any, of
any other Lease Event of Default and with the consent of the Secured Parties,
without notice to the Pledgor, any such notice being expressly waived by the
Pledgor, to set-off and appropriate and apply any and all deposits (general or
special, time or demand, provisional or final), in any currency, and any other
credits, indebtedness or claims, in any currency, in each case whether direct
or indirect, absolute or contingent, matured or unmatured, at any time held or
owing by the Collateral Agent or such Secured Party to or for the credit or the
account of the Pledgor, or any part thereof in such amounts as the Collateral
Agent or such Secured Party may elect, against and on account of the
obligations and liabilities of the Pledgor to the Collateral Agent or such
Secured Party hereunder and claims of every nature and description of the


                                       10
<Page>

Collateral Agent or such Secured Party against the Pledgor, in any currency,
whether arising hereunder, under the Participation Agreement, any other
Operative Document or otherwise, as the Collateral Agent or such Secured Party
may elect, whether or not the Collateral Agent or any Secured Party has made
any demand for payment and although such obligations, liabilities and claims
may be contingent or unmatured. The Collateral Agent and each Secured Party
shall notify the Pledgor promptly of any such set-off and the application made
by the Collateral Agent or such Secured Party of the proceeds thereof, PROVIDED
that the failure to give such notice shall not affect the validity of such
set-off and application. The rights of the Collateral Agent and each Secured
Party under this SECTION 7.5 are in addition to other rights and remedies
(including, without limitation, other rights of set-off) which the Collateral
Agent or such Secured Party may have.

           7.6   COUNTERPARTS. This Agreement may be executed by one or more of
the parties to this Agreement on any number of separate counterparts (including
by telecopy), 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 which 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   SECTION HEADINGS. The Section headings used in this Agreement
are for convenience of reference only and are not to affect the construction
hereof or be taken into consideration in the interpretation hereof.

           7.9   INTEGRATION. The Security Documents represent the agreement of
the Pledgors, the Collateral Agent and the Secured Parties with respect to the
subject matter hereof and thereof, and there are no promises, undertakings,
representations or warranties by the Collateral Agent or any Secured Party
relative to subject matter hereof and thereof not expressly set forth or
referred to in the Security Documents. The Security Documents supersede any and
all prior agreements and understandings, oral or written, relative or with
respect to the subject matter hereof, and there are no promises, undertakings,
representations or warranties by the Collateral Agent or any Secured Party
relative to the subject matter hereof not expressly set forth or referred to
herein or in the other Security Documents.

           7.10  GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

           7.11  SUBMISSION TO JURISDICTION; WAIVERS. The Pledgor (and, with
respect to paragraph (e) below only, the Collateral Agent and each of the
Secured Parties) hereby irrevocably and unconditionally:

           (a)   submits for itself and its property in any legal action or
proceeding relating to the Operative Documents to which it is a party, or for
recognition and enforcement of any judgment in respect thereof, to the
non-exclusive general jurisdiction of the Courts of the State of


                                       11
<Page>

New York, the courts of the United States of America for the Southern District
of New York, and appellate courts from any thereof;

           (b)   consents that any such action or proceeding may be brought in
such courts and waives any objection that it may now or hereafter have to the
venue of any such action or proceeding in any such court or that such action or
proceeding was brought in an inconvenient court and agrees not to plead or
claim the same;

           (c)   agrees that service of process in any such action or
proceeding may be effected by mailing a copy thereof by registered or certified
mail (or any substantially similar form of mail), postage prepaid, to the
Pledgor at its address referred to in SECTION 7.2 or at such other address of
which the Collateral Agent shall have been notified pursuant thereto;

           (d)   agrees that nothing herein shall affect the right to effect
service of process in any other manner permitted by law or shall limit the
right to sue in any other jurisdiction; and

           (e)   waives, to the maximum extent not prohibited by law, any right
it may have to claim or recover in any legal action or proceeding referred to
in this Section any special, exemplary, punitive or consequential damages.

           7.12  ACKNOWLEDGEMENTS. The Pledgor hereby acknowledges that:

           (a)   it has been advised by counsel in the negotiation, execution
and delivery of the Security Documents to which it is a party;

           (b)   neither the Collateral Agent nor any Secured Party has any
fiduciary relationship with or duty to the Pledgor arising out of or in
connection with any Security Documents, and the relationship between the
Pledgor, on the one hand, and the Collateral Agent and Secured Parties, on the
other hand, in connection herewith or therewith is solely that of debtor and
creditor; and

           (c)   no joint venture is created by any Security Document or
otherwise exists by virtue of the transactions contemplated hereby among the
Secured Parties or among the Pledgor and the Secured Parties.

           7.13  RELEASES. (a) At such time as the Obligations shall have been
paid in full, the Collateral shall automatically be released from the Liens
created hereby, and this Agreement and all obligations (other than those
expressly stated to survive such termination) of the Collateral Agent and the
Pledgor hereunder shall terminate, all without delivery of any instrument or
performance of any act by any party, and all rights to the Collateral shall
revert to the Pledgors. At the request and sole expense of the Pledgor
following any such termination, the Collateral Agent shall deliver to the
Pledgor any Collateral held by the Collateral Agent hereunder, and execute and
deliver to the Pledgor such documents as the Pledgor shall reasonably request
to evidence such termination.

           (b)   If any of the Collateral shall be sold, transferred or
otherwise disposed of by the Pledgor in a transaction permitted by the
Participation Agreement, then the Collateral Agent, at the request and
reasonable and sole expense of the Pledgor, shall execute and deliver to


                                       12
<Page>

the Pledgor all releases or other documents reasonably necessary or desirable
for the release of the Liens created hereby on such Collateral.

           7.14  Security Interest Absolute.

           (a)   The obligations of the Pledgor under this Agreement are
independent of the Obligations and a separate action or actions may be brought
and prosecuted against the Pledgor to enforce this Agreement, irrespective of
whether any action is brought against another pledgor or any guarantor of the
Obligations or whether another pledgor or any guarantor of the Obligations is
joined in any such action or actions. All rights of the Owner Lessor and the
pledge, hypothecation and security interest hereunder, and all obligations of
the Pledgor hereunder, shall be absolute and unconditional, to the extent
permitted by Requirements of Law, irrespective of:

                       (i)    any lack of validity or enforceability of any
      Operative Document or any other agreement or instrument relating thereto;

                       (ii)   any change in the time, manner or place of
      payment of or in any other term of, all or any of the Obligations, or any
      other amendment or waiver of or any consent to any departure from any
      Operative Document, including, without limitation, any increase in the
      Obligations resulting from the extension of additional credit to the
      Pledgor;

                       (iii)  any taking, exchange, release or non-perfection
      of any other collateral, or any taking, release or amendment or waiver of,
      or consent to departure from any guaranty, for all or any of the
      Obligations;

                       (iv)   any manner of application of the Collateral, or
      proceeds thereof, to all or any of the Obligations, or any manner of sale
      or other disposition of any other collateral for all or any of the
      Obligations;

                       (v)    any change, restructuring or termination of the
      structure or existence of the Pledgor; or

                       (vi)   any other circumstances which might otherwise
      constitute a defense available to, or a discharge of, the Pledgor or a
      third party grantor of a security interest.

           The Pledgor hereby waives, to the maximum extent permitted by law
(i) all rights under any law limiting remedies, including recovery of a
deficiency, under an obligation secured by a mortgage or deed of trust on real
property if the real property is sold under a power of sale contained in the
mortgage, and all defenses based on any loss whether as a result of any such
sale or otherwise, of Pledgor's right to recover any amount, whether by right
of subrogation or otherwise; (ii) all rights under any law to require the Owner
Lessor to pursue the Pledgor, or any other Person, any security which Owner
Lessor may hold, or any other remedy before


                                       13
<Page>

proceeding against the Pledgor; (iii) all rights of reimbursement or
subrogation, all rights to enforce any remedy that the Owner Lessor may have
against the Pledgor, and all rights to participate in any security held by the
Owner Lessor until the Obligations have been paid and performed in full; (iv)
all rights to require the Owner Lessor to give any notices of any kind,
including, without limitation, notices of nonpayment, nonperformance, protest,
dishonor, default, delinquency or acceleration, or to make any presentments,
demands or protests, except as set forth herein or expressly provided in the
Participation Agreement; (v) all rights to assert the bankruptcy or insolvency
of the Pledgor as a defense hereunder or as the basis for rescission hereof;
(vi) all rights under any law purporting to reduce the Pledgor's obligations
hereunder if the Obligations are reduced; (vii) all defenses based on the
disability or lack of authority of the Pledgor or any Person, the repudiation
of the Operative Documents by the Pledgor or any Person, the failure by the
Owner Lessor to enforce any claim against the Pledgor, or the unenforceability
in whole or in part of any Operative Documents; (viii) all suretyship and
guarantor's defenses generally; (ix) all rights to insist upon, plead or in any
manner whatever claim or take the benefit or advantage of, any appraisal,
valuation, stay, extension, marshalling of assets, redemption or similar law,
or exemption, whether now or at any time hereafter in force, which may delay,
prevent or otherwise affect the performance by the Pledgor of its obligations
under, or the enforcement by the Owner Lessor of, this Agreement; (x) any
requirement on the part of the Owner Lessor to mitigate the damages resulting
from any default; and (xi) except as otherwise specifically set forth herein,
all rights of notice and hearing of any kind prior to the exercise of rights by
the Owner Lessor upon the occurrence and during the continuation of a Lease
Event of Default to repossess with judicial process or to replevy, attach or
levy upon the Collateral. To the extent permitted by law, the Pledgor waives
the posting of any bond otherwise required of the Owner Lessor in connection
with any judicial process or proceeding to obtain possession of, replevy,
attach, or levy upon the Collateral, to enforce any judgment or other security
for the Obligations, to enforce any judgment or other court order entered in
favor of Owner Lessor, or to enforce by specific performance, temporary
restraining order, preliminary or permanent injunction, this Agreement or any
other agreement or document between the Pledgor and the Owner Lessor. The
Pledgor further agrees that upon the occurrence and during the continuation of
a Lease Event of Default, the Collateral Agent may elect to nonjudicially or
judicially foreclose against any real or personal property security it holds
for the Obligations or any part thereof, or to exercise any other remedy
against the Pledgor, any security or any guarantor, even if the effect of that
action is to deprive the Pledgor of the right to collect reimbursement for any
sums paid by the Pledgor to the Collateral Agent.

           7.15  WAIVER OF JURY TRIAL. EACH PARTY HERETO HEREBY IRREVOCABLY AND
UNCONDITIONALLY WAIVES TRIAL BY JURY IN ANY LEGAL ACTION OR PROCEEDING RELATING
TO THIS AGREEMENT OR ANY OTHER OPERATIVE DOCUMENT AND FOR ANY COUNTERCLAIM
THEREIN.


                                       14
<Page>

           IN WITNESS WHEREOF, each of the undersigned has caused this
Agreement to be duly executed and delivered as of the date first above written.

                                      EME HOMER CITY GENERATION L.P.,


                                      By:   Mission Energy Westside, Inc.,
                                            its General Partner

                                      By:
                                            -----------------------------------
                                            Name:
                                            Title:


Acknowledged and Agreed as of the date hereof:
THE BANK OF NEW YORK, as successor to
UNITED STATES TRUST COMPANY OF
   NEW YORK, as Collateral Agent


By:
      -----------------------------------------------------
      Name:
      Title:




                                       15
<Page>

                                                                   SCHEDULE 1 to
                         AMENDED AND RESTATED GUARANTEE AND COLLATERAL AGREEMENT




                                NOTICE ADDRESSES


EME HOMER CITY GENERATION L.P.

18101 Von Karman Avenue
Suite 1700
Irvine, CA 92612-1046
Attention:   TreasurerTelephone:    949-752-5588 Facsimile:   949-752-5624




                                       16
<Page>

                                                                   SCHEDULE 2 to
                         AMENDED AND RESTATED GUARANTEE AND COLLATERAL AGREEMENT


                            FILINGS AND OTHER ACTIONS
                     REQUIRED TO PERFECT SECURITY INTERESTS

                         UNIFORM COMMERCIAL CODE FILINGS
<Table>
<Caption>
-------------------------------------------------------------------------------
PLEDGOR                                  UCC FILING OFFICES
-------------------------------------------------------------------------------
<S>                                     <C>
EME Homer City Generation L.P.           California Secretary of State
                                         Pennsylvania Secretary of State
                                         Indiana County, PA
-------------------------------------------------------------------------------
</Table>


                                       17
<Page>

                                                                   SCHEDULE 3 to
                         AMENDED AND RESTATED GUARANTEE AND COLLATERAL AGREEMENT


       LOCATION OF JURISDICTION OF ORGANIZATION AND CHIEF EXECUTIVE OFFICE

<Table>
<Caption>
PLEDGOR                                JURISDICTION               LOCATION
-------                                ------------               --------
<S>                                   <C>                        <C>
EME Homer City Generation L.P.         PA                         18101 Von Karman Avenue
                                                                  Suite 1700
                                                                  Irvine, California 92612-1046
</Table>


                                       18