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                                                                  EXECUTION COPY
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                                          FOURTH AMENDMENT, dated as of May 14,
                                          2001 (this "Fourth Amendment"), to the
                                          Credit Agreement dated as of April 28,
                                          2000 (as amended to the date hereof,
                                          the "Credit Agreement"), among ORION
                                          POWER MIDWEST, L.P., a Delaware
                                          limited partnership (the "Borrower"),
                                          BANC OF AMERICA SECURITIES LLC and
                                          GOLDMAN SACHS CREDIT PARTNERS L.P., as
                                          co-lead arrangers (collectively, the
                                          "Co-Lead Arrangers"), BNP PARIBAS and
                                          DEUTSCHE BANC ALEX. BROWN INC.
                                          (formerly known as Deutsche Bank
                                          Securities, Inc.)., as arrangers
                                          (together with the Co-Lead Arrangers,
                                          the "Arrangers"), BANK OF AMERICA,
                                          N.A., as administrative agent for the
                                          Lenders (in such capacity, together
                                          with any successors and assigns, the
                                          "Administrative Agent"), BANK OF
                                          AMERICA, N.A., as issuer of Letters of
                                          Credit (the "Issuing Bank"), GOLDMAN
                                          SACHS CREDIT PARTNERS L.P., BNP
                                          PARIBAS and DEUTSCHE BANK AG NEW YORK
                                          BRANCH, as syndication agents
                                          (collectively, the "Syndication
                                          Agents"), BANC OF AMERICA SECURITIES
                                          LLC and GOLDMAN SACHS CREDIT PARTNERS
                                          L.P., as joint book runners (the
                                          "Joint Book Runners"), BNP PARIBAS and
                                          DEUTSCHE BANK AG NEW YORK BRANCH, as
                                          documentation agents (collectively,
                                          the "Documentation Agents"), and each
                                          other financial institution which is a
                                          signatory thereto or which may become
                                          an assignee pursuant to Section 9.06
                                          of the Credit Agreement (each a
                                          "Lender", and collectively the
                                          "Lenders")


         This Fourth Amendment is entered into by and among (i) the Borrower,
(ii) the Administrative Agent, (iii) the Issuing Bank, (iv) each of the Lenders
signatory hereto, on behalf of all of the Lenders, in accordance with Section
9.02 of the Credit Agreement, (v) the Arrangers, (vi) the Syndication Agents,
(vii) the Documentation Agents and (viii) the Joint Book Runners.

         WHEREAS, the Borrower, the Arrangers, the Joint Book Runners, the
Issuing Bank, the Administrative Agent, the Syndication Agents, the
Documentation Agents and the Lenders are parties to the Credit Agreement; and

         WHEREAS, the Borrower has requested certain amendments to the Credit
Agreement; and

         WHEREAS, the Borrower has requested the Required Lender's consent to
certain new contracts and to certain amendments to existing contracts as
provided below; and
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         WHEREAS, the Lenders signatory hereto are willing to agree to those
amendments and to give those consents on the terms, and subject to the
conditions, hereinafter set forth;

         Accordingly, in consideration of the agreements herein contained, the
parties hereby agree as follows:

         Section 1.01 Definitions. Unless otherwise defined herein or unless the
context otherwise requires, all capitalized terms used in this Fourth Amendment,
including its preamble and recitals, have the meanings assigned to them in the
Credit Agreement. In addition, the following terms shall have the following
meanings:

                  "Allegheny Supply Contract" shall mean the EEI/MENA Master
Power Purchase and Sale Agreement dated April 30, 2001 by and between the
Borrower and Allegheny Energy Supply Co., L.L.C., together with the Transaction
Confirmation between the Borrower and Allegheny Energy Supply Co., L.L.C.,
executed on March 28, 2001 by the Borrower and on April 3, 2001 by Allegheny.

                  "Acquisition Loan Prepayment Amount" shall mean the aggregate
sum of $22,000,000.

                  "Dominion Supply Contract" shall mean the EEI/MENA Master
Power Purchase and Sale Agreement dated May 31, 2000 by and between the Borrower
and CNG Retail Services Corporation (now known as Dominion Retail, Inc.),
together with the Transaction Confirmation between Borrower and Dominion Retail,
Inc. executed on March 29, 2001 by the Borrower and on March 27, 2001 by
Dominion.

                  "Management Services Agreement" shall mean the Management
Services Agreement dated of even date herewith by and between the Borrower and
Twelvepole.

                  "Operating Account Deposit" shall mean the aggregate sum of
$10,000,000.

                  "Replacement Cap Ex Deposit" shall mean the aggregate sum of
$5,000,000.

                  "Revolving Loan Reduction Amount" shall mean the aggregate sum
of $15,000,000.

         Section 1.02   (a) Amendment to Section 5.21(d). Section 5.21(d) of the
Credit Agreement is hereby deleted from the Credit Agreement in its entirety.

         (b) Amendment to Section 5.26(c). Section 5.26(c) of the Credit
Agreement is hereby deleted from the Credit Agreement in its entirety.

         Section 1.03   Amendment to Section 6.13. Section 6.13 of the Credit
Agreement is hereby deleted in its entirety and the following is hereby
substituted therefor:

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"Section 6.13 Debt Service Coverage Ratio". "(a) On the Quarterly Payment Date
occurring on June 30, 2001, fail to either (i) maintain a Debt Service Coverage
Ratio of at least 1.30 to 1.00 for the three-month period immediately preceding
such date, or (ii) with the proceeds of an equity contribution from the Sponsor,
deposit in the Prepayment Account the sum of $25,000,000 for the prepayment of
principal of Acquisition Loans on terms reasonably required by and reasonably
acceptable to the Administrative Agent, (b) on the Quarterly Payment Date
occurring on September 30, 2001, fail to maintain a Debt Service Coverage Ratio
of at least 1.50 to 1.00 for the three-month period immediately preceding such
date, (c) on the Quarterly Payment Date occurring on December 31, 2001, fail to
maintain a Debt Service Coverage Ratio of at least 1.50 to 1.00 for the
six-month period immediately preceding such date, or (d) on any Quarterly
Payment Date occurring on or after March 31, 2002, fail to maintain an average
annual Debt Service Ratio of at least 1.50 to 1.00 for the twelve-month period
immediately preceding any date of determination of such Debt Service Coverage
Ratio."

         Section 1.04   Consent to Ceredo Lease Amendment. The undersigned
Lenders hereby consent to the Borrower's execution and delivery of the amendment
to the Ceredo Lease Agreement, a copy of which amendment is attached hereto as
Exhibit A.

         Section 1.05   Consent to Allegheny Supply Contract. The undersigned
Lenders hereby consent to the Borrower's execution and delivery of the Allegheny
Supply Contract, a copy of which contract is attached hereto as Exhibit B. With
regard to the Allegheny Supply Contract, the undersigned Lenders hereby waive
the Borrower's obligation to deliver an Additional Contract Consent as required
by the terms of Section 5.22(b).

         Section 1.06   Consent to Dominion Supply Contract. The undersigned
Lenders hereby consent to the Borrower's execution and delivery of the Dominion
Supply Contract, a copy of which contract is attached hereto as Exhibit C. With
regard to the Dominion Supply Contract, the undersigned Lenders hereby waive the
Borrower's obligation to deliver an Additional Contract Consent as required by
the terms of Section 5.22(b).

         Section 1.07   Management Services Agreement. The undersigned Lenders
hereby consent to the Borrower's and Twelvepole's execution and delivery of a
Management Services Agreement with each other, a copy of which agreement is
attached is hereto as Exhibit D. In that regard, the form of Management Services
Agreement attached to the Credit Agreement as Exhibit Y thereto is hereby
deleted in its entirety and the Management Services Agreement attached as
Exhibit D to this Fourth Amendment is hereby substituted therefor.

         Section 1.08   2001 Budget. The undersigned Lenders hereby consent to
the revised Operating Budget for the fiscal year 2001 delivered of even date
herewith to the Arrangers and the Lenders and agree that such revised Operating
Budget shall be the effective Operating Budget for Borrower's fiscal year 2001
as of the Fourth Amendment Effective Date.

         Section 1.09   Representations and Warranties. The Borrower hereby
represents and warrants to each Lender and the Administrative Agent, on the
Fourth Amendment Effective Date, as follows:

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         (a) After giving effect to the amended Schedules to the Credit
Agreement that are attached to this Fourth Amendment as Exhibit E, the
representations and warranties set forth in Article IV of the Credit Agreement,
and in each other Financing Document, are true and correct in all material
respects on and as of the date hereof and on and as of the Fourth Amendment
Effective Date (as herein after defined) with the same effect as if made on and
as of the date hereof or the Fourth Amendment Effective Date, as the case may
be, except to the extent such representations and warranties expressly relate
solely to an early date.

         (b) Each of the Borrower and the other Credit Parties is in compliance
with all terms and conditions of the Credit Agreement and the other Financing
Documents on its part to be observed and performed and no Default or Event of
Default has occurred and is continuing.

         (c) The execution, delivery and performance by the Borrower of this
Fourth Amendment has been duly authorized by the Borrower.

         (d) This Fourth Amendment constitutes the legal, valid and binding
obligation of the Borrower, enforceable in accordance with its terms.

         (e) The execution, delivery and performance by the Borrower of this
Fourth Amendment (i) do not and will not contravene (A) its or any other Credit
Party's Governing Documents or (B) any material Requirement of Law or any
material Governmental Approval binding on or affecting it or any other Credit
Party, and (ii) do not and will not conflict with or be inconsistent with or
result in any breach of any of the terms, covenants, conditions or provisions
of, or constitute a Default under, or result in the creation or imposition of
(or the obligation to create or impose) any Lien (except Permitted Liens) upon
any of its or any other Credit Party's properties or assets pursuant to, the
terms of any material Contractual Obligation binding on or effecting it or any
other Credit Party.

         Section 1.10   Effectiveness. This Fourth Amendment shall become
effective only upon satisfaction of the following conditions precedent (the
first date upon which each such condition has been satisfied being herein called
the "Fourth Amendment Effective Date"):

         (a) The Administrative Agent shall have received duly executed
counterparts of this Fourth Amendment which, when taken together, bear the
authorized signatures of the Borrower and the Required Lenders.

         (b) The Administrative Agent and the Required Lenders shall be
satisfied that the representations and warranties set forth in Section 1.07 of
this Fourth Amendment are true and correct on and as of the Fourth Amendment
Effective Date and that no Default or Event of Default has occurred and is
continuing on and as of the Fourth Amendment Effective Date.

         (c) The Administrative Agent shall have received a supplemental report
from Pace Global Energy Services, LLC, as Fuel and Power Marketing Consultant to
the Arrangers, in form and substance reasonably satisfactory to the
Administrative Agent and the Required Lenders.

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         (d) The Administrative Agent shall have received a supplemental report
from Stone & Webster, as Independent Engineer for the Arrangers, in form and
substance reasonably acceptable to the Administrative Agent and the Required
Lenders.

         (e) The Administrative Agent shall have received, for the account of
each of the Lenders signatory hereto (i) on or before May 14, 2001 for each
Lender that has executed and delivered this Agreement on or prior to 5:00 p.m.
U.S. eastern daylight time on May 14, 2001, an amendment fee in an amount equal
to .20% times of the sum of (x) such Lender's outstanding Loans on the Fourth
Amendment Effective Date (calculated net of such Lender's ratable portion of
prepayments to be made as contemplated by clause (h) below), plus (y) such
Lender's Letter of Credit Exposure on the Fourth Amendment Effective Date, plus
(z) the unutilized amount of such Lender's Commitments on the Fourth Amendment
Effective Date, and (ii) on or before May 22, 2001 for each Lender that has
executed and delivered this Agreement on or prior to 5:00 p.m. U.S. eastern
daylight time on May 22, 2001, but after May 14, 2001, an amendment fee equal to
 .10% times the sum of (x) such Lender's outstanding Loans on the Fourth
Amendment Effective Date (calculated net of such Lender's ratable portion of
prepayments to be made as contemplated by clause (h) below), plus (y) such
Lender's Letter of Credit Exposure on the Fourth Amendment Effective Date, plus
(z) the unutilized amount of such Lender's Commitments on the Fourth Amendment
Effective Date.

         (f) The Administrative Agent shall have received all fees and expenses
to be paid by the Borrower pursuant to Section 1.10 of this Fourth Amendment.

         (g) The Borrower shall have received from the Sponsor and caused to be
deposited in the Equity Proceeds Account an equity contribution from the Sponsor
in the aggregate amount of $52,000,000. The proceeds of this equity contribution
from the Sponsor shall have been used to satisfy the conditions set forth in
subparagraphs (h), (i), (j) and (k) of this Section 1.10.

         (h) The Administrative Agent shall have received from the Borrower in
cash the Acquisition Loan Prepayment Amount, together with a certificate from a
Responsible Officer of the Borrower directing the Administrative Agent to prepay
Acquisition Loans in the amount of the Acquisition Loan Prepayment Amount (in
accordance with and pursuant to the terms of Section 2.08(a) of the Credit
Agreement) on the earliest date possible without incurring Funding Breakage
Costs. The Acquisition Loan Prepayment Amount will be held in the Prepayment
Account and applied to prepay Acquisition Loans on the earliest date possible
after the date hereof without incurring Funding Breakage Costs provided, that,
any such amount held in the Prepayment Account shall be applied to repay
Acquisition Loans immediately and automatically upon the occurrence of any event
affecting any Credit Party described in Section 7.07 of the Credit Agreement or
upon the occurrence of any Event of Default, and in all events prior to June 15,
2001.

         (i) The Administrative Agent shall have received from the Borrower in
cash the Revolving Loan Reduction Amount, together with a certificate from a
Responsible Officer of the Borrower directing the Administrative Agent to repay
existing outstanding Revolving Loans in the amount of the Revolving Loan
Reduction Amount in accordance with the terms of the Credit


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Agreement. It is understood that the repayment of Revolving Loans contemplated
above is not a reduction of Revolving Loan Commitments.

         (j) The Administrative Agent shall have received from the Borrower in
cash the Replacement Cap Ex Deposit, together with a certificate from a
Responsible Officer of the Borrower directing the Administrative Agent to
deposit the Replacement Cap Ex Deposit in the Replacement Capital Expenditure
Pre-Funding Account to be held and disbursed in accordance with the terms of the
Deposit Account Agreement.

         (k) The Administrative Agent shall have received from the Borrower in
cash the Operating Account Deposit, together with a certificate from a
Responsible Officer of the Borrower directing the Administrative Agent to
deposit the Operating Account Deposit in the Operating Account to be held and
disbursed in accordance with the terms of the Deposit Account Agreement.

         (l) The Administrative Agent shall have received duly executed
counterparts of the Ceredo Lease Amendment, the Allegheny Supply Contract, the
Dominion Supply Contract, the Management Services Agreement and all documents
and instruments contemplated by Section 5.22(b) of the Credit Agreement relating
to the Allegheny Supply Agreement and the Dominion Supply Contract other than
Additional Contract Consents in respect of each such contract.

         (m) There shall not be any action pending or any judgment, order or
decree in effect which, in the judgment of the Administrative Agent or the
Required Lenders, is likely to restrain, prevent or impose materially adverse
conditions upon the performance by the Borrower or any other Credit Party of its
obligations under the Credit Agreement.

         (n) The Administrative Agent shall have received such other documents,
legal opinions, instruments and certificates relating to this Fourth Amendment
as they shall reasonably request and such other documents, legal opinions,
instruments and certificates that shall be satisfactory in form and substance to
the Administrative Agent and the Required Lenders. All partnership and other
proceedings taken or to be taken in connection with this Fourth Amendment and
documents incidental thereto whether or not referred to herein shall be
satisfactory in form and substance to the Administrative Agent and the Required
Lenders.

         Section 1.11   Expenses. The Borrower shall pay all reasonable
out-of-pocket expenses incurred by Administrative Agent and the Lenders in
connection with the preparation, negotiation, execution, delivery and
enforcement of this Fourth Amendment, including, but not limited to, the
reasonable fees and disbursements of counsel to the Administrative Agent.

         Section 1.12   Cross-References. References in this Fourth Amendment to
any Section are, unless otherwise specified, to such Section of this Fourth
Amendment.

         Section 1.13   Instrument Pursuant to Credit Agreement. This Fourth
Amendment is a Financing Document executed pursuant to the Credit Agreement and
shall (unless otherwise expressly indicated herein) be construed, administered
and applied in accordance with the terms and provisions of the Credit Agreement.

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         Section 1.14   Further Acts. Each of the parties to this Fourth
Amendment agrees that at any time and from time to time upon the written request
of any other party, it will execute and deliver such further documents and do
such further acts and things as such other party may reasonably request in order
to effect the purposes of this Fourth Amendment.

         Section 1.15   Governing Law; Submission to Jurisdiction; Waiver of
Jury Trial.

         (a) THIS FOURTH AMENDMENT SHALL BE GOVERNED BY AND INTERPRETED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK OTHER THAN ANY SUCH
REQUIREMENT OF LAWS THAT WOULD APPLY THE LAWS OF ANOTHER JURISDICTION, EXCEPT TO
THE EXTENT THAT THE LAWS OF ANOTHER JURISDICTION ARE MANDATORILY APPLICABLE. ANY
DISPUTE ARISING OUT OF, CONNECTED WITH, RELATED TO, OR INCIDENTAL TO THE
RELATIONSHIP ESTABLISHED BETWEEN THE BORROWER AND EACH OF THE LENDERS, THE
ARRANGERS, THE ISSUING BANK AND THE ADMINISTRATIVE AGENT (COLLECTIVELY WITH THE
BORROWER, THE "FOURTH AMENDMENT PARTIES") IN CONNECTION WITH THIS AGREEMENT AND
THE OTHER FINANCING DOCUMENTS, AND WHETHER ARISING IN CONTRACT, TORT, EQUITY OR
OTHERWISE, SHALL BE RESOLVED IN ACCORDANCE WITH THE INTERNAL LAWS (AS OPPOSED TO
THE CONFLICTS OF LAWS PROVISIONS) AND DECISIONS OF THE STATE OF NEW YORK.

         (b) EACH OF THE FOURTH AMENDMENT PARTIES AGREE THAT ALL DISPUTES
BETWEEN THEM ARISING OUT OF, CONNECTED WITH, RELATED TO, OR INCIDENTAL TO THE
RELATIONSHIP ESTABLISHED BETWEEN THEM IN CONNECTION WITH THIS FOURTH AMENDMENT,
AND WHETHER ARISING IN CONTRACT, TORT, EQUITY, OR OTHERWISE, SHALL BE RESOLVED
ONLY BY STATE OR FEDERAL COURTS LOCATED IN NEW YORK, NEW YORK, BUT EACH OF THE
FOURTH AMENDMENT PARTIES ACKNOWLEDGE THAT ANY APPEALS FROM THOSE COURTS MAY HAVE
TO BE HEARD BY A COURT LOCATED OUTSIDE OF NEW YORK, NEW YORK. THE BORROWER
WAIVES IN ALL DISPUTES ANY OBJECTION THAT IT MAY HAVE TO THE LOCATION OF THE
COURT CONSIDERING THE DISPUTE INCLUDING, WITHOUT LIMITATION, ANY OBJECTION TO
THE LAYING OF VENUE OR BASED ON THE GROUNDS OF FORUM NON CONVENIENS.

         (c) THE FOURTH AMENDMENT PARTIES EACH WAIVE ANY RIGHT TO HAVE A JURY
PARTICIPATE IN RESOLVING ANY DISPUTE, WHETHER SOUNDING IN CONTRACT, TORT, OR
OTHERWISE ARISING OUT OF, CONNECTED WITH, RELATED TO OR INCIDENTAL TO THE
RELATIONSHIP ESTABLISHED BETWEEN THEM IN CONNECTION WITH THIS FOURTH AMENDMENT.
INSTEAD, ANY DISPUTES RESOLVED IN COURT WILL BE RESOLVED IN A BENCH TRIAL
WITHOUT A JURY.

         Section 1.16   Counterparts. This Fourth Amendment may be executed in
any number of counterparts and by the different parties hereto in separate
counterparts, each of which


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when so executed and delivered shall be an original, but all of which shall
together constitute one and the same instrument.

         Section 1.17   Severability. In case any provision in or obligation
under this Fourth Amendment or the other Financing Documents shall be invalid,
illegal or unenforceable in any jurisdiction, the validity, legality and
enforceability of the remaining provisions or obligations, or of such provision
or obligation in any other jurisdiction, shall not in any way be affected or
impaired thereby.

         Section 1.18   Benefit of Agreement. This Fourth Amendment shall be
binding upon and inure to the benefit of and be enforceable by the respective
successors and assigns of the parties hereto; provided that the Borrower may not
assign or transfer any of its interest hereunder without the prior written
consent of the Lenders.

         Section 1.19   Integration. This Fourth Amendment represents the
agreement of the Borrower, the Administrative Agent, the Issuing Bank, the
Arrangers and each of the Lenders signatory hereto with respect to the subject
matter hereof, and there are no promises, undertakings, representations or
warranties relative to the subject matter hereof not expressly set forth or
referred to herein or in the other Financing Documents.

         Section 1.20   Confirmation. Except as expressly amended by the terms
hereof, all of the terms of the Credit Agreement and the other Financing
Documents shall continue in full force and effect and are hereby ratified and
confirmed in all respects.


                           [Signature Pages to Follow]



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         IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart
of this Fourth Amendment to be duly executed and delivered as of the date first
above written.

BORROWER:
                                          ORION POWER MIDWEST, L.P.
                                          a Delaware limited partnership

                                          By:    Orion Power MidWest GP, Inc.,
                                                 its general partner


                                          By:____________________________
                                               Name:
                                               Title:

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REQUIRED LENDERS,
ADMINISTRATIVE AGENT,
ISSUING BANK AND ARRANGERS:


                           BANC OF AMERICA SECURITIES LLC, as a
                                Co-Lead Arranger


                           By:____________________________
                                Name:
                                Title:



                           GOLDMAN SACHS CREDIT PARTNERS L.P., as a Co-Lead
                           Arranger, a Revolving Lender and an Acquisition
                           Lender


                           By:
                              _________________________________________________
                                Name:
                                Title:


                           BNP PARIBAS, as an Arranger, a Revolving Lender and
                           an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:



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                           DEUTSCHE BANC ALEX. BROWN INC., as an Arranger


                           By:
                              _________________________________________________
                                Name:
                                Title:


                           By:
                              _________________________________________________
                                Name:
                                Title:



                           BANK OF AMERICA, N.A., as Administrative Agent,
                           Issuing Bank, a Revolving Lender and an Acquisition
                           Lender


                           By:____________________________
                                Name:
                                Title:


                           DEUTSCHE BANK AG NEW YORK AND/OR CAYMAN ISLAND
                           BRANCH, as a Revolving Lender and an Acquisition
                           Lender


                           By:
                              _________________________________________________
                                Name:
                                Title:


                           By:
                              _________________________________________________
                                Name:
                                Title:



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                           THE BANK OF NOVA SCOTIA, as a Revolving Lender and an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:



                           BAYERISCHE HYPO- UND VEREINSBANK AG, NEW YORK BRANCH,
                           as a Revolving Lender and an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:


                           DEXIA- CREDIT LOCAL DE FRANCE, as a Revolving Lender
                           and an Acquisition Lender


                           By:
                              _________________________________________________
                                Name:
                                Title:


                           By:
                              _________________________________________________
                                Name:
                                Title:


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                           DG BANK DEUTSCHE GENOSSENSHAFTSBANK AG, as a
                           Revolving Lender and an Acquisition Lender


                           By:____________________________
                               Name:
                               Title:


                           By:____________________________
                               Name:
                               Title:



                           DRESDNER BANK AG, NEW YORK AND GRAND CAYMAN BRANCHES,
                           as a Revolving Lender and an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:


                           ING (U.S.) CAPITAL LLC, as a Revolving Lender and an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:


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<PAGE>   14
                           SOCIETE GENERALE, as a Revolving Lender and an
                           Acquisition Lender


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



                           UNION BANK OF CALIFORNIA, N.A., as a Revolving Lender
                           and an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           ABN AMRO BANK N.V., as a Revolving Lender and an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:



                           COBANK, ACB, as a Revolving Lender and an Acquisition
                           Lender


                           By:____________________________
                                Name:
                                Title:


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<PAGE>   15
                           CREDIT LYONNAIS NEW YORK BRANCH, as a Revolving
                           Lender and an Acquisition Lender


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



                           THE DAI-ICHI KANGYO BANK, LIMITED, as a Revolving
                           Lender and an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           FLEET NATIONAL BANK, as a Revolving Lender and an
                           Acquisition Lender


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


                           THE FUJI BANK, LIMITED, as a Revolving Lender and an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


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<PAGE>   16
                           NORDDEUTSCHE LANDESBANK GIROZENTRALE, NEW YORK/GRAND
                           CAYMAN ISLANDS BRANCH, as a Revolving Lender and an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:


                           THE ROYAL BANK OF SCOTLAND PLC, as a Revolving Lender
                           and an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:



                           ABBEY NATIONAL TREASURY SERVICES PLC, as an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:



                           BANK ONE, NA, as an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


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<PAGE>   17
                           BARCLAYS BANK PLC, as an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:



                           LLOYDS TSB BANK PLC, as an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:


                           THE GOVERNOR AND COMPANY OF THE BANK OF SCOTLAND, as
                           an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:



                           SUMITOMO MITSUI BANKING CORPORATION (formerly known
                           as The Sumitomo Bank, Limited, and as successor by
                           merger to The Sakura Bank, Limited), as an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


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<PAGE>   18
                           AIB CAPITAL MARKETS PLC, as an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           BANCA NAZIONALE DEL LAVORO S.P.A., NEW YORK BRANCH,
                           as an Acquisition Lender

                           By:____________________________
                                Name:
                                Title:

                           By:____________________________
                                Name:
                                Title:



                           CREDIT INDUSTRIEL ET COMMERCIAL, as an Acquisition
                           Lender


                           By:____________________________
                                Name:
                                Title:



                           THE INDUSTRIAL BANK OF JAPAN, LIMITED, as an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                                       18
<PAGE>   19
                           LANDESBANK SCHLESWIG-HOLSTEIN GIROZENTRALE, as an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:


                           NATIONAL CITY BANK OF PENNSYLVANIA, as an Acquisition
                           Lender


                           By:____________________________
                                Name:
                                Title:


                           THE GOVERNOR AND COMPANY OF THE BANK OF IRELAND, as
                           an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           By:____________________________
                                Name:
                                Title:




                                       19
<PAGE>   20
                           ERSTE BANK DER OESTERREICHISCHEN SPARKASSEN AG, as an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:


                           THE SANWA BANK LIMITED, NEW YORK BRANCH, as an
                           Acquisition Lender


                           By:____________________________
                                Name:
                                Title:



                           COOPERATIEVE CENTRALE RAIFFEISEN-BOERENLEENBANK B.A.,
                           as an Acquisition Lender


                           By:____________________________
                                Name:
                                Title:




                                       20
<PAGE>   21
                                    EXHIBIT A
                                    ---------

                             CEREDO LEASE AMENDMENT
<PAGE>   22
                                    EXHIBIT B
                                    ---------

                            ALLEGHENY SUPPLY CONTRACT
<PAGE>   23
                                    EXHIBIT C
                                    ---------

                            DOMINION SUPPLY CONTRACT
<PAGE>   24
                                    EXHIBIT D
                                    ---------

                          MANAGEMENT SERVICES AGREEMENT
<PAGE>   25
                                    EXHIBIT E
                                    ---------

                      AMENDED SCHEDULES TO CREDIT AGREEMENT