June 1, 2001 Monongahela Power Company 1310 Fairmont Avenue Fairmont, West Virginia 26554 Attn: Thomas C. Sheppard, Jr. Chase Manhattan Trust Company, National Association as Successor Trustee under the Security Agreements referred to in the...

                                                                                                   June 1, 2001



Monongahela Power Company
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Attn: ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇, ▇▇.

▇▇▇▇▇ Manhattan Trust Company, National Association
   as Successor Trustee under the Security Agreements
   referred to in the Assumption and Indemnity Agreement
   (as defined below)
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Attn: ▇▇▇▇▇▇ ▇. ▇▇▇▇

▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇, as Individual Trustee
   under the Deed of Trust and Security
   Agreement of Monongahela Power Company,
   dated as of November 1, 1997, as supplemented
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Re:     Assumption under Assumption and
Indemnity Agreement (as defined below)

Ladies and Gentlemen:

           Reference is made to the Assumption and Indemnity Agreement, dated as of June 1, 2001 (the "Assumption and Indemnity Agreement"), among MP Generating Company, a Delaware limited liability company ("Indemnitor"), Monongahela Power Company, an Ohio corporation ("Issuer"), and the Holder, as defined therein. Capitalized terms used herein shall have the meaning ascribed to them in the Assumption and Indemnity Agreement.

MP Generating has merged into Allegheny Energy Supply Company, LLC, (the "Company") on the date hereof.

Pursuant to Section 4.2 of the Assumption and Indemnity Agreement, the Company, in connection with such merger, hereby assumes and covenants to be solely liable and responsible for and to perform all obligations of MP Generating under the Assumption and Indemnity Agreement. Such assumption and covenant shall be effective as of the date hereof.

                                                                     Truly yours,


                                                                     Allegheny Energy Supply Company, LLC


                                                                     By:      /S/ ▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                                                                 Name:  ▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                                                                 Title:   Vice President

ACKNOWLEDGED BY:
MONONGAHELA POWER COMPANY


By:       /S/ ▇▇▇▇▇ ▇. ▇▇▇▇▇                                         Dated as of June 1, 2001
Name:  ▇▇▇▇▇ ▇. ▇▇▇▇▇
Title:    Vice President

ACKNOWLEDGED BY:
CHASE MANHATTAN TRUST COMPANY,
NATIONAL ASSOCIATION, AS SUCCESSOR
TRUSTEE, AS HOLDER

By:       /S/ ▇. ▇. ▇▇▇▇                                             Dated as of June 1, 2001
Name:  ▇.▇. ▇▇▇▇
Title:    Vice President

                                                                                                   August 1, 2000



The Potomac Edison Company
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Attn: ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇, ▇▇.

▇▇▇▇▇ Manhattan Trust Company, National Association
   as Successor Trustee under the Security Agreements
   referred to in the Assumption and Indemnity Agreement
   (as defined below)
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Att: ▇▇▇▇▇▇ ▇. ▇▇▇▇

▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇, as Individual Trustee
   under the Deed of Trust and Security
   Agreement of The Potomac Edison Company,
   dated November 1, 1997, as supplemented
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Re: Assumption under Assumption and
Indemnity Agreement (as defined below)

Ladies and Gentlemen:

          Reference is made to the Assumption and Indemnity Agreement, dated August 1, 2000, among PE Transferring Agent, LLC, a Delaware limited liability company ("Indemnitor"), The Potomac Edison Company ("Issuer"), and the Holder, as defined therein (the "Assumption and Indemnity Agreement"). Capitalized terms used herein shall have the meaning ascribed to them in the Assumption and Indemnity Agreement.

          As of the date hereof, PE Generating Company, LLC, a Delaware limited liability company ("PE Generating") has, pursuant to a Letter of Assumption (the "Letter"), assumed and covenanted to be solely liable and responsible for and to perform all obligations of Indemnitor under the Assumption and Indemnity Agreement.

          PE Generating has merged with Allegheny Energy Supply Company, LLC, (the "Company") on the date hereof.

          Pursuant to Section 4.2 of the Assumption and Indemnity Agreement, the Company, in connection with such merger, hereby assumes and covenants to be solely liable and responsible for and to perform all obligations of PE Generating under the Assumption and Indemnity Agreement and the Letter. Such assumption and covenant shall be effective as of the date hereof.

                                                                     Truly yours,

                                                                     Allegheny Energy Supply Company, LLC


                                                                     By:     /S/ ▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                                                               NAME:  ▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                                                               TITLE:   President

ACKNOWLEDGED BY:
THE POTOMAC EDISON COMPANY


By:       /S/ ▇▇▇▇▇ ▇▇▇▇▇▇                                           Dated as of July, 2000
Name:  ▇▇▇▇▇ ▇▇▇▇▇▇
Title:    Vice President

ACKNOWLEDGED BY:
CHASE MANHATTAN TRUST COMPANY,
NATIONAL ASSOCIATION, AS SUCCESSOR
TRUSTEE, AS HOLDER


By:       /S/ ▇. ▇. ▇▇▇▇                                             Dated as of July, 2000
Name: ▇.▇. ▇▇▇▇
Title:   Vice President

                                                                                                   November 18, ▇▇▇▇



▇▇▇▇ ▇▇▇▇ Power Company
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Attn: ▇▇▇▇▇ ▇. ▇▇▇▇

▇▇▇▇▇ Manhattan Trust Company, National Association
  as Trustee under the Security Agreements
  referred to in the Assumption and Indemnity Agreement
  as defined herein
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Att: ▇▇▇▇▇▇ ▇. ▇▇▇▇

▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇, as Individual Trustee
under the Deed of Trust and Security
Agreement of West Penn Power Company,
dated November 1, 1997, as supplemented
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Gentlemen:


          Reference is made to the Assumption and Indemnity Agreement, dated November 17, 1999, between West Penn Transferring Agent LLC, a Pennsylvania limited liability company ("Indemnitor"), West Penn Power Company ("Issuer") and the Holder, as defined therein (the "Assumption and Indemnity Agreement"). Capitalized terms used herein shall have the meaning ascribed to them in the Assumption and Indemnity Agreement.

          Indemnitor has agreed to transfer to Allegheny Energy Supply Company, LLC, (the "Company"), and the Company has agreed to accept and acquire, on the date hereof, all or substantially all of the Mortgaged Facilities or Mortgaged Site, as such terms are defined in the Security Agreements.

          Pursuant to Section 4.2 of the Assumption and Indemnity Agreement, the Company, in connection with such acceptance and acquisition, hereby assumes and covenants to be solely liable and responsible for and to perform all obligations of Indemnitor under the Assumption and Indemnity Agreement. Such assumption and covenant shall be effective as of the date hereof.

                                                                     Truly yours,

                                                                     Allegheny Energy Supply Company, LLC


                                                                     By:     /S/ ▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                                                               Name:   ▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                                                               Title:    President

ACKNOWLEDGED BY:
WEST PENN POWER COMPANY


By:        /S/ ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇            Dated November 18, 1999
Name:   ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇▇
Title:     Vice President

ACKNOWLEDGED BY:
CHASE MANHATTAN TRUST COMPANY,
NATIONAL ASSOCIATION, AS HOLDER


By:       /S/ ▇. ▇. ▇▇▇▇                                             Dated as of November 18, 1999
Name: ▇.▇. ▇▇▇▇
Title:   Vice President