Document:

<PAGE>

================================================================================

                      CREDIT AND REIMBURSEMENT AGREEMENT

                                  dated as of

                                April 25, 2001

                                     among

                               PPL Montana, LLC,
                                 as Borrower,

                           THE CHASE MANHATTAN BANK,
                           as Administrative Agent,

                JP MORGAN, A DIVISION OF CHASE SECURITIES INC.,
                       as Lead Arranger and Book Runner,

                           THE BANK OF NOVA SCOTIA,
                             as Syndication Agent,

                    THE INDUSTRIAL BANK OF JAPAN, LIMITED,
                            as Documentation Agent

                                      and

                           THE LENDERS PARTY HERETO

                      __________________________________

                                 $150,000,000

================================================================================
<PAGE>

                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                            Page
<S>                                                                                         <C>
ARTICLE I DEFINITIONS..................................................................        1

   SECTION 1.01.    Defined Terms......................................................        1
   SECTION 1.02.    Classification of Loans and Borrowings.............................       23
   SECTION 1.03.    Terms Generally....................................................       23
   SECTION 1.04.    Accounting Terms; GAAP.............................................       23

ARTICLE II THE CREDITS.................................................................       24

   SECTION 2.01.    Commitments........................................................       24
   SECTION 2.02.    Letters of Credit..................................................       24
   SECTION 2.03.    Loans and Borrowings...............................................       28
   SECTION 2.04.    Interest Election Requests.........................................       29
   SECTION 2.05.    Funding of Borrowings..............................................       30
   SECTION 2.06.    Termination and Reduction of Commitments...........................       30
   SECTION 2.07.    Repayment of Loans; Evidence of Debt...............................       31
   SECTION 2.08.    Prepayment of Loans................................................       32
   SECTION 2.09.    Fees...............................................................       32
   SECTION 2.10.    Interest...........................................................       33
   SECTION 2.11.    Alternate Rate of Interest.........................................       34
   SECTION 2.12.    Increased Costs....................................................       35
   SECTION 2.13.    Break Funding Payments.............................................       36
   SECTION 2.14.    Taxes..............................................................       37
   SECTION 2.15.    Payments Generally; Pro Rata Treatment; Sharing of Set-offs........       38
   SECTION 2.16.    Mitigation Obligations; Replacement of Lenders.....................       40

ARTICLE III REPRESENTATIONS AND WARRANTIES.............................................       41

   SECTION 3.01.    Organization; Powers...............................................       41
   SECTION 3.02.    Authorization; Enforceability......................................       41
   SECTION 3.03.    Governmental Approvals; No Conflicts...............................       41
   SECTION 3.04.    Financial Condition; No Material Adverse Change....................       42
   SECTION 3.05.    Properties.........................................................       42
   SECTION 3.06.    Litigation and Environmental Matters...............................       43
   SECTION 3.07.    Compliance with Laws and Agreements................................       43
   SECTION 3.08.    Investment and Holding Company Status..............................       43
   SECTION 3.09.    Taxes..............................................................       43
   SECTION 3.10.    ERISA..............................................................       43
   SECTION 3.11.    Disclosure.........................................................       44
   SECTION 3.12.    Subsidiaries.......................................................       44
   SECTION 3.13.    Insurance..........................................................       44
   SECTION 3.14.    Labor Matters......................................................       44
   SECTION 3.15.    Solvency...........................................................       45
   SECTION 3.16.    Federal Reserve Regulations........................................       45
</TABLE>

                                       i
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<TABLE>
   <S>                                                                                          <C>
   SECTION 3.17.    No Burdensome Restrictions...............................................    45
   SECTION 3.18.    Energy Regulation........................................................    45
   SECTION 3.19.    Letters of Credit........................................................    46

ARTICLE IV CONDITIONS........................................................................    46

   SECTION 4.01.    Closing Date.............................................................    46
   SECTION 4.02.    Each Credit Event........................................................    49

ARTICLE V AFFIRMATIVE COVENANTS..............................................................    49

   SECTION 5.01.    Financial Statements and Other Information...............................    49
   SECTION 5.02.    Notices of Material Events...............................................    51
   SECTION 5.03.    Public Filings...........................................................    51
   SECTION 5.04.    Existence; Conduct of Business...........................................    51
   SECTION 5.05.    Payment of Obligations...................................................    51
   SECTION 5.06.    Maintenance of Properties................................................    52
   SECTION 5.07.    Insurance................................................................    52
   SECTION 5.08.    Books and Records; Inspection and Audit Rights; Auditor..................    52
   SECTION 5.09.    Compliance with Laws.....................................................    52
   SECTION 5.10.    Use of Proceeds and Letters of Credit....................................    52
   SECTION 5.11.    Additional Subsidiaries..................................................    52
   SECTION 5.12.    Energy Regulation........................................................    53
   SECTION 5.13.    Further Assurances.......................................................    53
   SECTION 5.14.    Power Marketing Plan.....................................................    53
   SECTION 5.15.    Ownership of Core Subsidiaries...........................................    53

ARTICLE VI NEGATIVE COVENANTS................................................................    53

   SECTION 6.01.    Indebtedness.............................................................    53
   SECTION 6.02.    Liens....................................................................    55
   SECTION 6.03.    Fundamental Changes......................................................    55
   SECTION 6.04.    Asset Sales..............................................................    55
   SECTION 6.05.    Restricted Payments; Certain Payments of Indebtedness....................    56
   SECTION 6.06.    Transactions with Affiliates.............................................    57
   SECTION 6.07.    Amendment of Material Documents..........................................    57
   SECTION 6.08.    Guarantees and Indemnities...............................................    58
   SECTION 6.09.    Fiscal Year..............................................................    58
   SECTION 6.10.    Ownership of Core Subsidiaries...........................................    58
   SECTION 6.11.    Debt to Capital Ratio....................................................    58
   SECTION 6.12.    Additional Subsidiaries and Core Subsidiaries............................    58
   SECTION 6.13.    Letters of Credit........................................................    59

ARTICLE VII EVENTS OF DEFAULT................................................................    59

ARTICLE VIII THE ADMINISTRATIVE AGENT........................................................    62

ARTICLE IX MISCELLANEOUS.....................................................................    64

   SECTION 9.01.    Notices..................................................................    64
</TABLE>

                                      ii
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<TABLE>
   <S>                                                                                     <C>
   SECTION 9.02.    Waivers; Amendments.................................................    64
   SECTION 9.03.    Expenses; Indemnity; Damage Waiver..................................    66
   SECTION 9.04.    Successors and Assigns..............................................    67
   SECTION 9.05.    Survival............................................................    69
   SECTION 9.06.    Counterparts; Integration; Effectiveness............................    70
   SECTION 9.07.    Severability........................................................    70
   SECTION 9.08.    Right of Setoff.....................................................    70
   SECTION 9.09.    Governing Law; Jurisdiction; Consent to Service of Process..........    70
   SECTION 9.10.    WAIVER OF JURY TRIAL................................................    71
   SECTION 9.11.    Headings............................................................    71
   SECTION 9.12.    Confidentiality.....................................................    71
   SECTION 9.13.    Interest Rate Limitation............................................    72
   SECTION 9.14.    Nonliability of Documentation Agent.................................    73
</TABLE>

                                      iii
<PAGE>

Schedules
---------
Schedule 1.01        Subordination Terms for Subordinated Indebtedness
Schedule 2.01:       Lenders and Commitments
Schedule 3.05:       Real Property
Schedule 3.06:       Disclosed Matters
Schedule 3.12:       Subsidiaries
Schedule 3.13:       Insurance
Schedule 4.01(h):    Search Jurisdictions
Schedule 4.01(k):    Governmental Approvals
Schedule 6.02:       Liens

Exhibits
--------
Exhibit A:           Form of Assignment and Acceptance
Exhibit B:           Form of Subsidiary Guarantee Agreement
Exhibit C:           Form of Letter of Credit
Exhibit D:           Form of Letter of Credit Request
Exhibit E:           Form of Borrowing Request
Exhibit F:           Form of Interest Election Request

                                      iv
<PAGE>

          CREDIT AND REIMBURSEMENT AGREEMENT, dated as of April 25, 2001 (this
"Agreement"), among PPL MONTANA, LLC, a Delaware limited liability company, as
the borrower (the "Borrower"), THE CHASE MANHATTAN BANK, as administrative agent
(in such capacity, the "Administrative Agent"), JP Morgan, a division of Chase
Securities Inc., as lead arranger and book runner (in such capacity, the "Lead
Arranger"), The Bank of Nova Scotia, as syndication agent (in such capacity, the
"Syndication Agent"), THE INDUSTRIAL BANK OF JAPAN, LIMITED, as documentation
agent (in such capacity, the "Documentation Agent") and the financial
institutions from time to time party hereto (in such capacity, the "Lenders").

          The parties hereto agree as follows:

                                   ARTICLE I

                                  Definitions

          SECTION 1.01.  Defined Terms. As used in this Agreement, the following
                         -------------
terms have the meanings specified below:

          "ABR," when used in reference to any Loan or Borrowing, refers to
whether such Loan, or the Loans comprising such Borrowing, are bearing interest
at a rate determined by reference to the Alternate Base Rate.

          "Additional Subsidiary" means any Subsidiary that becomes an
Additional Subsidiary in accordance with the requirements of Section 6.12.
                                                             ------------

          "Adjusted LIBO Rate" means, with respect to any Eurodollar Borrowing
for any Interest Period, an interest rate per annum (rounded upwards, if
necessary, to the next 1/16 of 1%) equal to (a) the LIBO Rate for such Interest
Period multiplied by (b) the Statutory Reserve Rate.

          "Administrative Agent" means The Chase Manhattan Bank, in its capacity
as administrative agent for the Lenders hereunder and includes each of its
successors and assigns.

          "Administrative Questionnaire" means an Administrative Questionnaire
in a form supplied by the Administrative Agent.

          "Affiliate" means, with respect to a specified Person, another Person
that directly, or indirectly through one or more intermediaries, Controls or is
Controlled by or is under common Control with the Person specified.

          "Alternate Base Rate" means, for any day, a rate per annum equal to
the greatest of (a) the Prime Rate in effect on such day, (b) the Base CD Rate
in effect on such day plus 1%, and (c) the Federal Funds Effective Rate in
effect on such day plus 1/2 of 1%. Any change in the Alternate Base Rate due to
a change in the Prime Rate, the Base CD Rate or the Federal Funds Effective Rate
shall be effective from and including the effective date of such change in the
Prime Rate, the Base CD Rate or the Federal Funds Effective Rate, respectively.
<PAGE>

          "Applicable Percentage" means, with respect to any Lender, the
percentage of the total Commitments represented by such Lender's Commitment.

          "Applicable Rate" means, at any date, the applicable rate per annum
determined in accordance with the following pricing grid:

<TABLE>
<CAPTION>
===================================================================================================================

                 Status                      Level I       Level II      Level III       Level IV       Level V
-------------------------------------------------------------------------------------------------------------------
<S>                                          <C>           <C>           <C>             <C>            <C>
Facility Fee Rate                            0.175%           0.20%          0.25%        0.375%         0.625%
-------------------------------------------------------------------------------------------------------------------
Applicable Rate-Eurodollar Loans             0.825%          0.925%          1.00%        1.875%         2.125%
-------------------------------------------------------------------------------------------------------------------
Applicable Rate-ABR Loans                     0.00%          0.125%          0.25%         1.25%          1.75%
-------------------------------------------------------------------------------------------------------------------
Participation Fee Rate for Letters of        0.825%          0.925%          1.00%        1.875%         2.125%
Credit
===================================================================================================================
</TABLE>

For purposes of this definition, the following terms have, subject to the
proviso below, the following meanings:

     "Level I Status" exists at any date if, at such date, the Relevant Debt is
      --------------
     rated both BBB+ or higher by S&P and Baa1 or higher by Moody's.

     "Level II Status" exists at any date if, at such date (i) the Relevant Debt
      ---------------
     is rated both BBB or higher by S&P and Baa2 or higher by Moody's and (ii)
     Level I Status does not exist.

     "Level III Status" exists at any date if, at such date (i) the Relevant
      ----------------
     Debt is rated both BBB- or higher by S&P and Baa3 or higher by Moody's and
     (ii) neither Level I Status nor Level II Status exists.

     "Level IV Status" exists at any date if, at such date (i) the Relevant Debt
      ---------------
     is rated both BB+ or higher by S&P and Ba1 or higher by Moody's and (ii)
     none of Level I Status, Level II Status and Level III Status exists.

     "Level V Status" exists at any date if, at such date, (i) the Relevant Debt
      --------------
     is not rated both BB+ or higher by S&P and Ba1 or higher by Moody's and
     (ii) none of Level I Status, Level II Status, Level III Status and Level IV
     Status exists.

     "Status" refers to the determination which of Level I Status, Level II
      ------
     Status, Level III Status, Level IV Status or Level V Status exists at any
     date.

     "Relevant Debt" refers to the Lease Debt or, if the Borrower's senior
      -------------
     unsecured long-term debt is then rated by S&P and Moody's, such debt;

provided, however, that: (a) if the ratings assigned to the Relevant Debt by S&P
and Moody's are "split" (e.g., a rating of "BBB+" from S&P and a rating of
"Baa2" from Moody's), the lower of the S&P and Moody's ratings shall apply
unless (1) the rating assigned to the Relevant Debt by Fitch IBCA, Inc. is
equivalent to the higher of the S&P and Moody's ratings and (2) the S&P and
Moody's ratings do not vary by more than one level, in which case the higher of
the S&P

                                       2
<PAGE>

and Moody's ratings shall apply; and (b) if Moody's or S&P has not assigned a
rating to the Relevant Debt, for purposes of this definition Level II Status
shall be deemed to exist, provided that if (i) the Relevant Debt is subsequently
assigned ratings by S&P and Moody's, (ii) the Relevant Debt has not been
previously assigned a rating by Moody's or S&P and (iii) as a result of such
ratings, Level III Status, Level IV Status or Level V Status exists, such Level
III Status, Level IV Status or Level V Status, as the case may be, shall be
deemed to have existed at all times prior to the actual assignment of such
rating for purposes of calculating the facility fees payable under Section
                                                                   -------
2.09(a).
-------

          "Assessment Rate" means, for any day, the annual assessment rate in
effect on such day that is payable by a member of the Bank Insurance Fund
classified as "well-capitalized" and within supervisory subgroup "B" (or a
comparable successor risk classification) within the meaning of 12 C.F.R. Part
327 (or any successor provision) to the Federal Deposit Insurance Corporation
for insurance by such Corporation of time deposits made in dollars at the
offices of such member in the United States; provided that if, as a result of
any change in any law, rule or regulation, it is no longer possible to determine
the Assessment Rate as aforesaid, then the Assessment Rate shall be such annual
rate as shall be determined by the Administrative Agent to be representative of
the cost of such insurance to the Lenders.

          "Asset Sale" means (i) any sale, transfer or other disposition
(including pursuant to a sale and leaseback transaction) of any property or
asset of the Borrower or any Core Subsidiary, in one transaction or in a series
of related transactions, (ii) the issuance and sale of any Equity Interest by
any Core Subsidiary to any Person other than the Borrower or a Core Subsidiary,
or (iii) any designation of a Core Subsidiary as an Additional Subsidiary (the
dollar amount of the Asset Sale made upon such designation to be determined as
the fair market value of all Investments made in such Core Subsidiary by the
Borrower or any of its Core Subsidiaries).

          "Assignment and Acceptance" means an assignment and acceptance entered
into by a Lender and an assignee (with the consent of any party whose consent is
required by Section 9.04), and accepted by the Administrative Agent, in the form
            ------------
of Exhibit A or any other form approved by the Administrative Agent.
   ---------

          "Availability Period" means the period from and including the Closing
Date to but excluding the earlier of (a) the Maturity Date and (b) the date of
termination of the Commitments.

          "Base CD Rate" means the sum of (a) the Three-Month Secondary CD Rate
multiplied by the Statutory Reserve Rate plus (b) the Assessment Rate.

          "Board" means the Board of Governors of the Federal Reserve System of
the United States of America.

          "Borrower" means PPL Montana, LLC, a Delaware limited liability
company.

          "Borrowing" means Loans of the same Type, made, converted or continued
on the same date and, in the case of Eurodollar Loans, as to which a single
Interest Period is in effect.

                                       3
<PAGE>

          "Borrowing Request" means a request by the Borrower for a Borrowing in
accordance with Section 2.03.
                ------------

          "Business Day" means any day that is not a Saturday, Sunday or other
day on which commercial banks in New York City are authorized or required by law
to remain closed; provided that, when used in connection with a Eurodollar Loan,
the term "Business Day" shall also exclude any day on which banks are not open
for dealings in dollar deposits in the London interbank market.

          "Capital Expenditures" means, for any period with respect to any
Person, (a) the capital expenditures of such Person that are (or would be) set
forth in a consolidated statement of cash flows of such Person for such period
prepared in accordance with GAAP and (b) Capital Lease Obligations incurred by
such Person during such period.

          "Capital Lease Obligations" of any Person means the obligations of
such Person to pay rent or other amounts under any lease of (or other
arrangement conveying the right to use) real or personal property, or a
combination thereof, which obligations are required to be classified and
accounted for as capital leases on a balance sheet of such Person under GAAP,
and the amount of such obligations shall be the capitalized amount thereof
determined in accordance with GAAP.

          "Cash Equivalents" means:

          (a)  direct obligations of, or obligations the principal of and
interest on which are unconditionally guaranteed by, the United States of
America (or by any agency thereof to the extent such obligations are backed by
the full faith and credit of the United States of America), in each case
maturing within one year from the date of acquisition thereof;

          (b)  investments in commercial paper maturing within 270 days from the
date of acquisition thereof and having, at such date of acquisition, the highest
credit rating obtainable from S&P or from Moody's;

          (c)  investments in certificates of deposit, banker's acceptances and
time deposits maturing within 180 days from the date of acquisition thereof
issued or guaranteed by or placed with, and money market deposit accounts issued
or offered by, any domestic office of any commercial bank organized under the
laws of the United States of America or any State thereof which has a combined
capital and surplus and undivided profits of not less than $500,000,000;

          (d)  fully collateralized repurchase agreements with a term of not
more than 60 days for securities described in clause (a) above and entered into
with a financial institution satisfying the criteria described in clause (c)
above; and

          (e)  other prudent short-term Investments which are made in the
ordinary course of business and consented to in writing by the Administrative
Agent (such consent not to be unreasonably withheld).

          "Cash Flow Available for Fixed Charges" for any period means, without
duplication, (a) Consolidated EBITDA (excluding all Additional Subsidiaries) for
such period,

                                       4
<PAGE>

minus (b) the portion of such Consolidated EBITDA that is attributable to cash
extraordinary gains or other cash nonrecurring revenue or credit items included
in Consolidated EBITDA (other than to the extent such cash extraordinary gains
or other cash nonrecurring revenue or credit items are offset by cash
extraordinary losses), minus (c) for each Core Subsidiary having an equity
holder other than the Borrower or any of its Core Subsidiaries, the amount
described in the foregoing clause (a) attributable to the Equity Interests owned
by such holder plus (d) Consolidated EBITDA (including the proceeds from any
asset sales) of Additional Subsidiaries for such period to the extent such
amount is distributed to the Borrower or its Core Subsidiaries from such
Additional Subsidiaries during such period, minus (e) Capital Expenditures made
by the Borrower and its Core Subsidiaries during such period other than capital
expenditures financed (i) with Indebtedness referred to in Section 6.01(a) or
                                                           --------------
(ii) with Indebtedness incurred pursuant to Section 6.01(b)(v).
                                            ------------------

          "Cash Flow to Fixed Charges Ratio" means, for any period, the ratio of
(a) Cash Flow Available for Fixed Charges for such period to (b) Fixed Charges
for such period.

          "Change in Control" means the consummation of any transaction or
series of related transactions (including any merger or consolidation) the
result of which is that any person (as such term is defined in Rule 13(d)(3)
under the Exchange Act), (other than (a) PPL Corporation or any of its
successors into which PPL Corporation has consolidated or merged, (b) any person
(as defined above) who comes to be a beneficial owner (as defined below)
directly or indirectly of more than 50% of the voting power of or economic
interest in PPL Corporation or (c) any of PPL Corporation's direct or indirect
wholly-owned Subsidiaries), becomes the "beneficial owner" (as such term is
defined in Rule 13(d)(3) under the Exchange Act, except that a person (as
defined above) shall be deemed to have "beneficial ownership" of all securities
that such person has the right to acquire, whether such right is currently
exercisable or is exercisable only upon the occurrence of a subsequent
condition), directly or indirectly, of more than 50% of the voting power of or
economic interests in the Borrower.

          "Change in Law" means (a) the adoption of any law, rule or regulation
after the date of this Agreement, (b) any change in any law, rule or regulation
or in the interpretation or application thereof by any Governmental Authority
after the date of this Agreement or (c) compliance by any Lender or the Issuing
Bank (or, for purposes of Section 2.12(b), by any lending office of such Lender
                          ---------------
or by such Lender's or the Issuing Bank's holding company, if any) with any
request, guideline or directive (whether or not having the force of law) of any
Governmental Authority made or issued after the date of this Agreement.

          "Closing Date" means the date on which the conditions specified in
Section 4.01 are satisfied (or waived in accordance with Section 9.02).
------------                                             ------------

          "Code" means the Internal Revenue Code of 1986, as amended from time
to time.

          "Colstrip Facility" means the 2,276 (gross) MW coal-fired electric
generating facility.

          "Colstrip Project Transmission Agreement" means the Colstrip Project
Transmission Agreement, dated as of May 6, 1981, as amended as of February 14,
1990,

                                       5
<PAGE>

December 30, 1996 and July 13, 1998, by and among MPC, Puget (successor to Puget
Sound Power & Light Company), Portland, PacifiCorp (successor to Pacific Power &
Light Company) and Avista Corporation (successor to the Washington Water Power
Company).

          "Colstrip Site" means the town of Colstrip, Rosebud County, Montana.

          "Commitment" means, with respect to each Lender, the commitment, if
any, of such Lender to make Loans and to acquire participations in Letters of
Credit hereunder, as such commitment may be (a) reduced from time to time
pursuant to Section 2.06 or 2.08 and (b) reduced or increased from time to time
            ------------    ----
pursuant to assignments by or to such Lender pursuant to Section 9.04. The
                                                         ------------
initial amount of each Lender's Commitment is set forth on Schedule 2.01, or in
                                                           -------------
the Assignment and Acceptance pursuant to which such Lender shall have assumed
its Commitment, as applicable. The initial aggregate amount of the Lenders'
Commitments is $150,000,000.

          "Common Facilities" means all facilities, improvements, fixtures, and
equipment constructed or installed for common use by Units 1, 2, 3 and 4 of the
Colstrip Facility.

          "Consolidated EBITDA" means, for any period, Consolidated Net Income
for such period plus (a) without duplication and to the extent deducted in
determining such Consolidated Net Income, the sum of (i) consolidated interest
expense for such period, (ii) consolidated income tax expense for such period,
(iii) all amounts attributable to depreciation and amortization for such period,
(iv) lease expense for such period attributable to the Facility Leases (as
defined in each Participation Agreement), (v) non-cash charges representing
allocations from Affiliates and (vi) any extraordinary non-cash charges or other
non-cash nonrecurring charge items for such period, and minus (b) without
duplication and to the extent included in determining such Consolidated Net
Income, any extraordinary non-cash gains or other non-cash nonrecurring revenue
or credit items for such period, all determined on a consolidated basis in
accordance with GAAP.

          "Consolidated Net Income" means, for any period, the net income or
loss of the Borrower and its Subsidiaries for such period determined on a
consolidated basis in accordance with GAAP; provided that there shall be
excluded (a) the income of any Person (other than a Core Subsidiary) in which
the Borrower or a Core Subsidiary or any director holding qualifying shares in
compliance with applicable law owns an Equity Interest, except to the extent of
the amount of dividends or other distributions actually paid to the Borrower or
any of its Subsidiaries during such period, and (b) the income or loss of any
Person accrued prior to the date it becomes a Core Subsidiary or is merged into
or consolidated with the Borrower or any Core Subsidiary or the date that such
Person's assets are acquired by the Borrower or any Core Subsidiary.

          "Consolidated Tangible Net Assets" means, at any date of
determination, (a) the total net assets of the Borrower and its Core
Subsidiaries determined in accordance with GAAP, excluding (i) goodwill,
organizational expenses, research and product development expenses, trademarks,
tradenames, copyrights, patents, patent applications, licenses and rights in any
thereof, and other similar intangibles, (ii) all deferred charges or unamortized
debt discount and expenses, (iii) all reserves carried and not deducted from
assets, (iv) securities which are not

                                       6
<PAGE>

readily marketable, (v) cash held in sinking or other analogous funds
established for the purpose of redemption, retirement or prepayment of capital
stock or other Equity Interests or Indebtedness, (vi) any write-up in the book
value of any assets resulting from a revaluation thereof subsequent to the
Closing Date and (vii) any items not included in clauses (i) through (vi) above
which are treated as intangibles in conformity with GAAP, plus (b) the aggregate
purchase price paid by the Owner Lessors for the Leased Assets, plus (c) the
aggregate net book value of all asset sales or dispositions made by the Borrower
or any of its Core Subsidiaries since the Closing Date to the extent that the
proceeds thereof or other consideration received therefor are not invested in
any Permitted Business of the Borrower or any of its Core Subsidiaries and are
not retained by the Borrower or any of its Core Subsidiaries.

          "Control" means the possession, directly or indirectly, of the power
to direct or cause the direction of the management or policies of a Person,
whether through the ability to exercise voting power, by contract or otherwise.
"Controlling" and "Controlled" have meanings correlative thereto.

          "Core Subsidiary" means any Subsidiary that is not an Additional
Subsidiary.

          "Credit Event Date" means the Closing Date and each other date on
which any Borrowing is made or any Letter of Credit is issued, amended, renewed
or extended.

          "Debt to Capital Ratio" means, with respect to the Borrower and its
Core Subsidiaries, the ratio, as of the end of the most recent fiscal quarter of
the Borrower for which internal financial statements are available, of (a) the
aggregate principal amount of Indebtedness of such Persons then outstanding,
determined on a consolidated basis in accordance with GAAP to (b) Total
Capitalization.

          "Default" means any event or condition which constitutes an Event of
Default or which upon notice, lapse of time or both would, unless cured or
waived, become an Event of Default.

          "Disclosed Matters" means the actions, suits and proceedings and the
environmental matters disclosed in Schedule 3.06 (as in effect on the Closing
                                   -------------
Date and as thereafter amended with the prior written consent of the Required
Lenders).

          "Documentation Agent" means The Industrial Bank of Japan, Limited, in
its capacity as documentation agent.

          "dollars" or "$" refers to lawful money of the United States of
America.

          "EnergyPlus Marketing Agreement" means an the Brokering and Contract
Management Agreement, dated as of December 17, 1999, between the Borrower and
PPL EnergyPlus Co., LLC, a Pennsylvania limited liability company, relating to
the marketing of power from the Montana Assets.

          "Environmental Laws" means all laws, rules, regulations, codes,
ordinances, orders, decrees, judgments, injunctions or notices issued,
promulgated or entered into by any Governmental Authority with jurisdiction over
the Borrower, any of its Subsidiaries, any of the

                                       7
<PAGE>

Montana Assets or the Facility Site, relating in any way to the environment
(including damages to natural resources), the management, release or threatened
release of any Hazardous Material or to health and safety matters, including any
permits, authorizations, filings, notices or other approvals issued, filed or
made thereunder.

          "Environmental Liability" means any liability, contingent or otherwise
(including any liability for damages, costs of environmental remediation, fines,
penalties or indemnities), of the Borrower or any Subsidiary directly or
indirectly resulting from or based upon (a) violation of any Environmental Law,
(b) the generation, use, handling, transportation, storage, treatment or
disposal of any Hazardous Materials, (c) exposure to any Hazardous Materials,
(d) the release or threatened release of any Hazardous Materials into the
environment or (e) any contract, agreement or other consensual arrangement
pursuant to which liability is assumed or imposed with respect to any of the
foregoing.

          "Equity Interests" means shares of capital stock, partnership
interests, membership interests in a limited liability company, beneficial
interests in a trust or other equity ownership interests in a Person.

          "ERISA" means the Employee Retirement Income Security Act of 1974, as
amended from time to time.

          "ERISA Affiliate" means any trade or business (whether or not
incorporated) that, together with the Borrower, is treated as a single employer
under Section 414(b) or (c) of the Code or, solely for purposes of Section 302
of ERISA and Section 412 of the Code, is treated as a single employer under
Section 414 of the Code.

          "ERISA Event" means (a) any "reportable event," as defined in Section
4043 of ERISA or the regulations issued thereunder with respect to a Plan (other
than an event for which the 30-day notice period is waived); (b) the existence
with respect to any Plan of an "accumulated funding deficiency" (as defined in
Section 412 of the Code or Section 302 of ERISA), whether or not waived; (c) the
filing pursuant to Section 412(d) of the Code or Section 303 of ERISA of an
application for a waiver of the minimum funding standard with respect to any
Plan; (d) the incurrence by the Borrower or any of its ERISA Affiliates of any
liability under Title IV of ERISA with respect to the termination of any Plan;
(e) the receipt by the Borrower or any ERISA Affiliate from the PBGC or a plan
administrator of any notice relating to an intention to terminate any Plan or
Plans or to appoint a trustee to administer any Plan; (f) the incurrence by the
Borrower or any of its ERISA Affiliates of any liability with respect to the
withdrawal or partial withdrawal from any Multiemployer Plan or the termination
of any Plan; or (g) the receipt by the Borrower or any ERISA Affiliate of any
notice concerning the determination that a Multiemployer Plan is, or is expected
to be, insolvent or in reorganization, within the meaning of Title IV of ERISA.

          "Eurodollar," when used in reference to any Loan or Borrowing, refers
to whether such Loan, or the Loans comprising such Borrowing, are bearing
interest at a rate determined by reference to the Adjusted LIBO Rate.

          "Event of Default" has the meaning assigned to such term in Article
                                                                      -------
VII.
---

                                       8
<PAGE>

          "Exchange Act" means the Securities Exchange Act of 1934, as amended.

          "Excluded Taxes" means, with respect to the Administrative Agent, any
Lender, the Issuing Bank or any other recipient of any payment to be made by or
on account of any obligation of the Borrower hereunder or under any other Loan
Document, (a) income or franchise taxes imposed on (or measured by) its net
income by the United States of America, or by the jurisdiction under the laws of
which such recipient is organized or in which its principal office is located
or, in the case of any Lender, in which its applicable lending office is located
and, in each case, any Governmental Authority thereof or therein, (b) any branch
profits taxes imposed by the United States of America or any similar tax imposed
by any other jurisdiction or Governmental Authority described in clause (a)
above and (c) in the case of a Foreign Lender (other than an assignee pursuant
to a request by the Borrower under Section 2.16(b), excluding, however, requests
                                   ---------------
caused by any Lender defaulting in its obligation to fund Loans hereunder), any
withholding tax that (i) is in effect and would apply to amounts payable to such
Foreign Lender at the time such Foreign Lender becomes a party to this Agreement
(or designates a new lending office), except to the extent that such Foreign
Lender (or its assignor, if any) was entitled, at the time of designation of a
new lending office (or assignment), to receive additional amounts from the
Borrower with respect to any withholding tax pursuant to Section 2.14(a), or
                                                         ---------------
(ii) is attributable to such Foreign Lender's failure to comply with Section
                                                                     -------
2.14(e).
-------

          "Exempt Wholesale Generator" means an "exempt wholesale generator," as
such term is defined in 15 U.S.C. (S) 79z-5a(a-1).

          "Existing Credit Agreement" means the Credit Agreement, dated as of
November 16, 1999, among the Borrower, The Chase Manhattan Bank, as
administrative agent, and the lenders from time to time party thereto.

          "Exposure" means, with respect to any Lender at any time, the
outstanding principal amount of such Lender's Loans and its LC Exposure at such
time.

          "Facility Site" means the undivided interest in that portion of the
Colstrip Site on which the Leased Assets are located.

          "Federal Funds Effective Rate" means, for any day, the weighted
average (rounded upwards, if necessary, to the next 1/100 of 1%) of the rates on
overnight Federal funds transactions with members of the Federal Reserve System
arranged by Federal funds brokers, as published on the next succeeding Business
Day by the Federal Reserve Bank of New York, or, if such rate is not so
published for any day that is a Business Day, the average (rounded upwards, if
necessary, to the next 1/100 of 1%) of the quotations for such day for such
transactions received by the Administrative Agent from three Federal funds
brokers of recognized standing selected by it.

          "FERC" means the Federal Energy Regulatory Commission.

          "Financial Officer" means a financial officer of the Borrower.

          "Fixed Charges" means, with respect to the Borrower and its Core
Subsidiaries for any period, the sum, without duplication, of (a) the aggregate
amount of interest expense with

                                       9
<PAGE>

respect to Indebtedness of such Persons for such period, including (i) the net
payments under interest rate Hedging Agreements (with payments to the Borrower
and any of its Core Subsidiaries to be subtracted and payments by the Borrower
and any of its Core Subsidiaries to be added), (ii) all capitalized interest and
(iii) the interest portion of any deferred payment obligation, plus (b) the
aggregate amount of all mandatory scheduled payments (whether designated as
payments or prepayments) and sinking fund payments with respect to principal of
any Indebtedness of such Persons, plus (c) the aggregate amount of all payments
due under the Lease Documents, in each case, scheduled to be paid by such Person
during such period; provided that the amounts referred to in clauses (a) and (b)
shall not include amounts owed in respect of any intercompany Indebtedness among
the Borrower and its Core Subsidiaries.

          "Foreign Lender" means any Lender that is organized under the laws of
a jurisdiction other than that in which the Borrower is located. For purposes of
this definition, the United States of America, each State thereof and the
District of Columbia shall be deemed to constitute a single jurisdiction.

          "GAAP" means generally accepted accounting principles in the United
States of America.

          "Governmental Authority" means the government of the United States of
America, any other nation with jurisdiction over the Borrower, any of its
Subsidiaries, any of the Montana Assets or the Facility Site, or any political
subdivision thereof, whether state or local, and any agency, authority,
instrumentality, regulatory body, court, central bank or other entity exercising
executive, legislative, judicial, taxing, regulatory or administrative powers or
functions of or pertaining to government.

          "Guarantee" of or by any Person (the "guarantor") means any
obligation, contingent or otherwise, of the guarantor guaranteeing or having the
economic effect of guaranteeing any Indebtedness or other obligation of any
other Person (the "primary obligor") in any manner, whether directly or
indirectly, and including any obligation of the guarantor, direct or indirect,
(a) to purchase or pay (or advance or supply funds for the purchase or payment
of) such Indebtedness or other obligation or to purchase (or to advance or
supply funds for the purchase of) any security for the payment thereof, (b) to
purchase or lease property, securities or services for the purpose of assuring
the owner of such Indebtedness or other obligation of the payment thereof, (c)
to maintain working capital, equity capital or any other financial statement
condition or liquidity of the primary obligor so as to enable the primary
obligor to pay such Indebtedness or other obligation or (d) as an account party
in respect of any letter of credit or letter of guaranty issued to support such
Indebtedness or obligation; provided, that the term Guarantee shall not include
endorsements for collection or deposit in the ordinary course of business.

          "Hazardous Materials" means all explosive or radioactive substances or
wastes and all hazardous or toxic substances, wastes or other pollutants,
including petroleum or petroleum distillates, asbestos or asbestos containing
materials, polychlorinated biphenyls, radon gas and all other substances or
wastes of any nature regulated pursuant to any Environmental Law.

                                       10
<PAGE>

          "Hedging Agreement" means any interest rate protection agreement,
foreign currency exchange agreement, commodity price protection agreement or
other interest or currency exchange rate or commodity price hedging arrangement,
including any annuity agreement purchased with the proceeds of, or converted
from, any other Hedging Agreement.

          "Indebtedness" of any Person means:

          (a)  all indebtedness of such Person for borrowed money,

          (b)  all obligations of such Person evidenced by bonds, debentures,
notes or other similar instruments,

          (c)  all obligations of such Person to pay the deferred purchase price
of property or services,

          (d)  all indebtedness created or arising under any conditional sale or
other title retention agreement with respect to property acquired by such Person
(even though the rights and remedies of the seller or lender under such
agreement upon the occurrence of an event of default are limited to repossession
or sale of such property),

          (e)  all Lease Obligations of such Person,

          (f)  all obligations, contingent or otherwise, of such Person under
acceptance, letter of credit or similar facilities,

          (g)  all unconditional obligations of such Person to purchase, redeem,
retire, defease or otherwise acquire for value any capital stock or other Equity
Interests of such Person or any warrants, rights or options to acquire such
capital stock or other Equity Interests,

          (h)  all Indebtedness of any other Person of the type referred to in
clauses (a) through (g) which is Guaranteed by such Person or for which such
Person shall otherwise (including pursuant to any keepwell, makewell or similar
arrangement) become directly or indirectly liable, and

          (i)  all third party Indebtedness of the type referred to in clauses
(a) through (g) above secured by (or for which the holder of such Indebtedness
has an existing right, contingent or otherwise, to be secured by) any Lien or
security interest on property (including accounts and contract rights) owned by
the Person whose Indebtedness is being measured, even though such Person has not
assumed or become liable for the payment of such third party Indebtedness, the
amount of such obligation being deemed to be the lesser of the value of such
property or the amount of the obligation so secured.

          "Indemnified Taxes" means Taxes other than Excluded Taxes.

          "Insurance Consultant" means AON Risk Services or any other Person
from time to time appointed by the Administrative Agent to act as insurance
consultant for purposes of this Agreement.

                                       11
<PAGE>

          "Interconnection Agreement" means the Generation Interconnection
Agreement, dated as of December 17. 1999, between the Borrower and MPC.

          "Interest Election Request" means a request by the Borrower to convert
or continue a Borrowing in accordance with Section 2.04.
                                           ------------

          "Interest Payment Date" means (a) with respect to any ABR Loan, the
last day of each March, June, September and December, and (b) with respect to
any Eurodollar Loan, the last day of the Interest Period applicable to the
Borrowing of which such Loan is a part and, in the case of a Eurodollar
Borrowing with an Interest Period of more than three months' duration, each day
prior to the last day of such Interest Period that occurs at intervals of three
months' duration after the first day of such Interest Period.

          "Interest Period" means, with respect to any Eurodollar Borrowing, the
period commencing on the date of such Borrowing and ending on the numerically
corresponding day in the calendar month that is one, two, three or six months
thereafter, as the Borrower may elect; provided that (i) if any Interest Period
would end on a day other than a Business Day, such Interest Period shall be
extended to the next succeeding Business Day unless such next succeeding
Business Day would fall in the next calendar month, in which case such Interest
Period shall end on the next preceding Business Day and (ii) any Interest Period
that commences on the last Business Day of a calendar month (or on a day for
which there is no numerically corresponding day in the last calendar month of
such Interest Period) shall end on the last Business Day of the last calendar
month of such Interest Period. For purposes hereof, the date of a Borrowing
initially shall be the date on which such Borrowing is made and, thereafter
shall be the effective date of the most recent conversion or continuation of
such Borrowing.

          "Investments" means, with respect to any Person, all direct or
indirect investments by such Person in other Persons (including Affiliates) in
the forms of loans (including Guarantees or other obligations), advances or
capital contributions, purchases or other acquisitions for consideration of
Indebtedness, Equity Interests or other securities, together with all items that
are or would be classified as investments on a balance sheet prepared in
accordance with GAAP.

          "Issuing Bank" means The Chase Manhattan Bank, in its capacity as the
issuer of Letters of Credit hereunder, and its successors in such capacity as
provided in Section 2.02(i). The Issuing Bank may, in its discretion, arrange
for one or more Letters of Credit to be issued by Affiliates of the Issuing
Bank, in which case the term "Issuing Bank" shall include any such Affiliate
with respect to Letters of Credit issued by such Affiliate.

          "LC Disbursement" means a payment made by the Issuing Bank pursuant to
a Letter of Credit.

          "LC Exposure" means, at any time, the sum of (a) the aggregate undrawn
amount of all outstanding Letters of Credit at such time plus (b) the aggregate
amount of all LC Disbursements that have not yet been reimbursed by or on behalf
of the Borrower at such time. The LC Exposure of any Lender at any time shall be
its Applicable Percentage of the total LC Exposure at such time.

                                       12
<PAGE>

          "Lead Arranger" means JP Morgan, a division of Chase Securities Inc.,
in its capacity as lead arranger.

          "Lease Debt" means Indebtedness incurred by any Owner Lessor and its
subsidiaries, if any, under the Lease Documents.

          "Lease Documents" means, collectively, the Pass Through Trust
Agreement, the Certificates, each Participation Agreement, and each Bill of
Sale, Facility Lease, Site Lease and Sublease, Assignment and Reassignment of
Project Agreements, Omnibus Voting Rights Agreement, Lease Indenture, Lessor
Note, LLC Agreement, OP Parent Guaranty and any Qualifying Letter of Credit, in
each case, as defined in the applicable Participation Agreement.

          "Lease Event of Default" means an "event of default" under and as
defined in a Lease.

          "Lease Obligations" means without duplication, (a) indebtedness
represented by obligations under a lease that is required to be capitalized for
financial reporting purposes, and (b) with respect to non-capital leases, (i)
the principal amount of non-recourse indebtedness of the lessor in such a lease,
or (ii) if such amount is indeterminable, then the present value, determined
using a discount rate equal to the incremental borrowing rate (as defined in
Statement of Financial Accounting Standards No. 13) of the lessee under a lease,
of rent obligations under such lease.

          "Lease Transactions" means the transactions contemplated by the Lease
Documents.

          "Leased Assets" means, collectively, the assets leased by the Borrower
pursuant to the Lease Documents.

          "Lenders" means the Persons listed on Schedule 2.01 and any other
                                                -------------
Person that shall have become a party hereto pursuant to an Assignment and
Acceptance, other than any such Person that ceases to be a party hereto pursuant
to an Assignment and Acceptance.

          "Letter of Credit" means any letter of credit issued pursuant to this
Agreement substantially in the form of Exhibit C hereto.
                                       ---------

          "Letter of Credit Request" means a request by the Borrower for a
Letter of Credit in accordance with Section 2.02.
                                    ------------

          "LIBO Rate" means, with respect to any Eurodollar Borrowing for any
Interest Period, the rate appearing on Telerate Page 3750 (or on any successor
or substitute for such Page providing rate quotations comparable to those
currently provided on such Page, as determined by the Administrative Agent from
time to time for purposes of providing quotations of interest rates applicable
to dollar deposits in the London interbank market) at approximately 11:00 a.m.,
London time, two Business Days prior to the commencement of such Interest
Period, as the rate for dollar deposits with a maturity comparable to such
Interest Period. In the event that such rate is not available at such time for
any reason, then the "LIBO Rate" with respect to such Eurodollar Borrowing for
such Interest Period shall be the rate at which dollar deposits of

                                       13
<PAGE>

$5,000,000 and for a maturity comparable to such Interest Period are offered by
the principal London office of the Administrative Agent in immediately available
funds in the London interbank market at approximately 11:00 a.m., London time,
two Business Days prior to the commencement of such Interest Period.

          "Lien" means, with respect to any asset, (a) any mortgage, deed of
trust, lien, pledge, hypothecation, encumbrance, charge or security interest in,
on or of such asset, (b) the interest of a vendor or a lessor under any
conditional sale agreement, capital lease or title retention agreement (or any
financing lease having substantially the same economic effect as any of the
foregoing) relating to such asset and (c) in the case of securities, any
purchase option, call or similar right of a third party with respect to such
securities.

          "Loan Documents" means this Agreement, the Subsidiary Guarantee
Agreement, the Parent Letter Agreement and each promissory note delivered
pursuant to this Agreement.

          "Loan Parties" means PPL Corporation, the Borrower and its Core
Subsidiaries.

          "Loan" means any loan made by the Lenders to the Borrower pursuant to
this Agreement.

          "Material Adverse Effect" means any event, development or circumstance
that has had or could reasonably be expected to have a material adverse effect
on (a) the business, assets, revenue, results of operations, condition
(financial or otherwise) or prospects of the Borrower and its Core Subsidiaries
taken as a whole (including any such effect resulting from an event, development
or circumstance affecting one or more Additional Subsidiaries), (b) the ability
of any Loan Party to perform its obligations under the Loan Documents to which
it is a party or (c) the validity or enforceability of any of the Loan Documents
or the rights and remedies of the Administrative Agent and the Lenders
thereunder.

          "Material Agreements" means, collectively, the Existing Credit
Agreement, the Wholesale Transition Service Agreements, the Interconnection
Agreement, the Operating Agreements, the Reciprocal Sharing Agreement, the
Colstrip Project Transmission Agreement (to the extent assigned to the Borrower
or a Core Subsidiary), the EnergyPlus Marketing Agreement and the Lease
Documents.

          "Material Indebtedness" means Indebtedness (other than the Loans and
Letters of Credit), including the Lease Debt and Indebtedness under the Existing
Credit Agreement, or obligations in respect of one or more Hedging Agreements,
of any one or more of the Borrower and its Subsidiaries in an aggregate
principal amount exceeding $10,000,000. For purposes of determining Material
Indebtedness, the "principal amount" of the obligations of the Borrower or any
Subsidiary in respect of any Hedging Agreement at any time shall be the maximum
aggregate amount (giving effect to any netting agreements), the Borrower or such
Subsidiary would be required to pay if such Hedging Agreement were terminated at
such time.

          "Maturity Date" means the day which is 364 days following the Closing
Date.

          "Montana Assets" means, collectively, the assets acquired by the
Borrower from MPC pursuant to the Asset Purchase Agreement, dated as of October
31, 1998, between PPL

                                       14

<PAGE>

Global and MPC on December 17, 1999 (including any expansions related thereto)
or any other generating or transmission assets located in North America acquired
by PPL Montana or any Core Subsidiary.

          "Moody's" means Moody's Investors Service, Inc.

          "MPC" means The Montana Power Company, a Montana corporation.

          "Multiemplover Plan" means a multiemployer plan as defined in Section
4001(a)(3) of ERISA.

          "Net Proceeds" means, (i) the cash proceeds received in respect of
such event including any cash received in respect of any non-cash proceeds, but
only as and when received, net of (ii) the sum of (A) all reasonable fees and
out-of-pocket expenses paid by the Borrower and its Subsidiaries to third
parties (other than Affiliates) in connection with such event, (B) in the case
of an Asset Sale, the amount of all payments required to be made by the Borrower
and its Subsidiaries as a result of such event to repay Indebtedness secured by
the asset or assets disposed of in such Asset Sale or otherwise subject to
mandatory prepayment as a result of such Asset Sale, and (C) the amount of all
taxes paid (or reasonably estimated to be payable) by the Borrower and its
Subsidiaries, and the amount of any reserves established by the Borrower and its
Subsidiaries to fund contingent liabilities reasonably estimated to be payable,
in each case during the year that such event occurred or the next succeeding
year and that are directly attributable to such event (as determined reasonably
and in good faith by the chief financial officer of the Borrower).

          "Non-Recourse Indebtedness" means Indebtedness:

          (a)  as to which neither the Borrower nor any of its Core Subsidiaries
(i) provides credit support of any kind (including any undertaking, agreement or
instrument that would constitute Indebtedness), (ii) is directly or indirectly
liable as a guarantor or otherwise, or (iii) is the lender;

          (b)  which, if in default, would not permit (upon notice, lapse of
time or both) any holder of any other Indebtedness of the Borrower or any of its
Core Subsidiaries to declare a default on such other Indebtedness or cause the
payment thereof to be accelerated or payable prior to its stated maturity
(including the right of such holders to take enforcement action against an
Additional Subsidiary); and

          (c)  as to which the lenders have been notified in writing that they
will not have any recourse to the Equity Interests or assets (other than the
Equity Interests of any Person other than a Core Subsidiary) of the Borrower or
any of its Core Subsidiaries.

          "Operating Agreements" means, collectively:

          (i)   the Agreement for the Operation and Maintenance of Colstrip
Steam Electric Generating Plant, dated as of July 30, 1971, between the Borrower
(successor to MPC) and Puget (successor to Puget Sound Power & Light Company);

                                       15
<PAGE>

          (ii)  the Construction and Ownership Agreement, dated as of July 30,
1971, between the Borrower (successor to MPC) and Puget (successor to Puget
Sound Power & Light Company);

          (iii) the Ownership and Operation Agreement--Colstrip Units 3 and 4,
dated as of May 6, 1981, as amended October 11, 1991 and July 13, 1998, among
the Borrower (successor to MPC), MPC, Puget (successor to Puget Sound Power &
Light Company and Puget Colstrip Construction Company), Avista Corporation
(successor to The Washington Water Power Company), Portland and PacifiCorp
(successor to Pacific Power & Light Company); and

          (iv)  the Common Facilities Agreement--Colstrip Units 1, 2, 3 and 4,
dated as of May 6, 1981, as amended January 21, 1992, among the Borrower
(successor to MPC), MPC, Puget (successor to Puget Sound Power & Light Company
and Puget Colstrip Construction Company), Avista Corporation (successor to The
Washington Water Power Company), Portland and PacifiCorp (successor to Pacific
Power & Light Company).

          "Other Taxes" means any and all present or future recording, stamp,
documentary, excise, transfer, sales, property or similar taxes, charges or
levies arising from any payment made under this Agreement or from the execution,
delivery or enforcement of, or otherwise with respect to, this Agreement.

          "Owner Lessors" means each "Owner Lessor," as defined in each
Participation Agreement.

          "Owner Lessor Liens" means each "Owner Lessor Lien," as defined in
each Participation Agreement.

          "Owner Participants" means each "Owner Participant," as defined in
each Participation Agreement.

          "Owner Participant Liens" means each "Owner Participant Lien," as
defined in each Participation Agreement.

          "Parent Letter Agreement" means the letter agreement dated as of the
Closing Date, among PPL Corporation, the Administrative Agent and the Borrower.

          "Participation Agreements" shall mean:

          (i)  the Participation Agreement (BA1/2), dated as of July 13, 2000,
among the Borrower, Montana OL3 LLC, as Owner Lessor, Wilmington Trust Company,
in its individual capacity and as Lessor Manager, Montana OP3 LLC, as Owner
Participant, and The Chase Manhattan Bank, as Lease Indenture Trustee and as
Pass Through Trustee,

          (ii) the Participation Agreement (BA3), dated as of July 13, 2000,
among the Borrower, Montana OL4 LLC, as Owner Lessor, Wilmington Trust Company,
in its individual capacity and as Lessor Manager, Montana OP4 LLC, as Owner
Participant, and The Chase Manhattan Bank, as Lease Indenture Trustee and as
Pass Through Trustee,

                                       16
<PAGE>

          (iii) the Participation Agreement (NC1/2), dated as of July 13, 2000,
among the Borrower, Montana OL1 LLC, as Owner Lessor, Wilmington Trust Company,
in its individual capacity and as Lessor Manager, Montana OP1 LLC, as Owner
Participant, and The Chase Manhattan Bank, as Lease Indenture Trustee and as
Pass Through Trustee, and

          (iv)  the Participation Agreement (NC3), dated as of July 13, 2000,
among the Borrower, Montana OL1 LLC, as Owner Lessor, Wilmington Trust Company,
in its individual capacity and as Lessor Manager, Montana OP1 LLC, as Owner
Participant, and The Chase Manhattan Bank, as Lease Indenture Trustee and as
Pass Through Trustee.

          "Pass-through Trust Agreement" shall mean the Pass Through Trust
Agreement, dated as of July 13, 2000, between the Borrower and The Chase
Manhattan Bank, as the Pass Through Trustee.

          "Pbgc" means the Pension Benefit Guaranty Corporation referred to and
defined in ERISA and any successor entity performing similar functions.

          "Permitted Business" means:

          (a) the generation, transmission, distribution, marketing and sale of
power from the Montana Assets;

          (b) activities related to the ownership and operation of the Rosebud
Coal Mine or other coal assets in North America for the supply of fuel to the
Montana Assets;

          (c) all activities related or incidental to those set forth in clauses
(a) and (b); and

          (d) any other activity related to non-nuclear generation,
transmission, distribution, marketing and sale of power in North America, so
long as Moody's and S&P confirm that the then-existing ratings assigned to the
Pass-Through Certificates will not fall below investment grade as a result of
the Borrower's and/or its Subsidiaries' participation in such activities.

          "Permitted Investment" means:

          (a) any Investment in the Borrower or in a Core Subsidiary;

          (b) any Investment in Cash Equivalents;

          (c) any Investment by the Borrower or any Core Subsidiary in a Person,
if as a result of such Investment, (i) such Person becomes a Core Subsidiary or
(ii) such Person is merged, consolidated or amalgamated with or into, or
transfers or conveys substantially all of its assets to, or is liquidated into,
the Borrower or a wholly-owned Core Subsidiary;

          (d) any acquisition of assets solely in exchange for the issuance of
Equity Interests of the Borrower;

          (e) any obligations incurred under a Hedging Agreement;

                                       17
<PAGE>

          (f) other Investments in any Person (including any Additional
Subsidiary) having an aggregate fair market value (measured on the date each
such Investment was made and without giving effect to subsequent changes in
value) that, together with all other Investments made pursuant to this clause
(f) since the Closing Date, is equal to or less than $10,000,000; and

          (g) any Investment made from the proceeds of capital contributions to,
or the issuance and sale of Equity Interests in, the Borrower not constituting
Indebtedness.

          "Permitted Liens" means:

          (a) Liens listed on Schedule 6.02 hereto;
                              -------------

          (b) Liens granted by the Borrower to any wholly-owned Core Subsidiary
or by a wholly-owned Core Subsidiary to the Borrower or any other wholly-owned
Core Subsidiary;

          (c) any Lien arising by reason of any judgment, decree or order of any
court so long as such Lien is being contested in good faith and is appropriately
bonded or reserved against, and any appropriate legal proceedings that may have
been duly initiated for the review of such judgment, decree or order have not
been finally terminated or the period within which such proceedings may be
initiated has not expired;

          (d) Liens arising by reason of taxes, duties or other governmental
charges that are not yet delinquent or are being contested in good faith;

          (e) Liens arising by reason of security for payment of worker's
compensation or other insurance;

          (f) Liens arising by operation of law in favor of carriers,
warehousemen, landlords, mechanics, materialmen, laborers or employees for sums
that are not yet delinquent or are being contested in good faith;

          (g) Liens in favor of suppliers incurred in the ordinary course of
business for sums that are not yet delinquent or are being contested in good
faith;

          (h) Liens arising by reason of easements, rights-of-way, zoning and
similar covenants and restrictions or similar encumbrances or title defects that
do not interfere with the ordinary course of business of the Borrower or any of
its Core Subsidiaries;

          (i) Liens arising by operation of law pursuant to any license issued
by the FERC required for the Borrower's operation of hydroelectric generation
facilities;

          (j) Liens to secure Indebtedness incurred pursuant to Section
                                                                -------
6.01(b)(iv), provided that such Liens do not cover assets which are, as a whole,
-----------
more valuable than the then current value of the assets covered by Liens
securing the Indebtedness being so refinanced;

          (k) the interests of the Borrower, the Owner Participants, the Owner
Lessors and the Lease Indenture Trustees under the Lease Documents;

                                       18
<PAGE>

          (l) Owner Lessor Liens and Owner Participant Liens;

          (m) the reversionary interests of (i) the Borrower in the Facility
Site and (ii) the Owner Lessors in the Leased Assets;

          (n) Liens to secure Indebtedness permitted to be incurred pursuant to
Section 6.01 (other than Indebtedness incurred pursuant to Section 6.01(b)(vi)),
------------                                               -------------------
provided that such Liens shall not secure Indebtedness in an amount in excess of
$25,000,000;

          (o) operating agreements or such other similar arrangements with
respect to the Common Facilities used by or useful to the Borrower or its Core
Subsidiaries which could not reasonably be expected to result in a material
adverse effect on (i) the business, assets, revenues, results of operations,
financial condition or prospects of the Borrower and its Core Subsidiaries,
taken as a whole, (ii) the ability of the Borrower or its Core Subsidiaries to
perform their respective obligations under the Loan Documents or (iii) the
validity or enforceability of Loan Documents or the rights and remedies of the
Lenders thereunder;

          (p) deposits to secure the performance of bids, trade contracts,
leases, statutory obligations, surety and appeal bonds, performance bonds and
other obligations of a like nature, in each case in the ordinary course of
business;

          (q) the interest of the lessor under a lease constituting a Capital
Lease Obligation and a purchase money security interest in property acquired
with the proceeds of purchase money Indebtedness permitted under Section 6.01;
                                                                 ------------

          (r) Liens arising by virtue of any statutory provisions relating to
banker's liens, rights of set-off or similar rights and remedies as to deposit
accounts or the funds maintained with a creditor depositary institution; and

          (s) Liens created or purported to be created pursuant to the
Subsidiary Guarantee Agreement.

          "Person" means any natural person, corporation, limited liability
company, trust, joint venture, association, company, partnership, Governmental
Authority or other entity.

          "Plan" means any employee pension benefit plan (other than a
Multiemployer Plan) subject to the provisions of Title IV of ERISA or Section
412 of the Code or Section 302 of ERISA, and in respect of which the Borrower or
any ERISA Affiliate is (or, if such plan were terminated, would under Section
4069 of ERISA be deemed to be) an "employer" as defined in Section 3(5) of
ERISA.

          "PPL Corporation" means PPL Corporation, a Pennsylvania corporation;
provided that if (a) any person (as such term is defined in Rule 13(d)(3) under
the Exchange Act) becomes a beneficial owner (as such term is defined in Rule
13(d)(3) under the Exchange Act, except that a person (as defined above) shall
be deemed to have "beneficial ownership" of all securities that such person has
the right to acquire, whether such right is currently exercisable or is
exercisable only upon the occurrence of a subsequent condition), directly or
indirectly, of more than 50% of the voting power of or economic interest in PPL
Corporation or (b) any event that is

                                       19
<PAGE>

not described in the definition of "Change of Control" occurs, pursuant to which
PPL Corporation merges into or consolidates with another entity and PPL
Corporation is not the surviving entity, then immediately after such event, in
the case of clause (a), "PPL Corporation" shall refer to the person so acquiring
more than 50% of the voting power of or economic interest in PPL Corporation or,
in the case of clause (b), "PPL Corporation" shall mean such surviving entity.

          "PPL Global" means PPL Global, LLC, a Delaware limited liability
company.

          "Prime Rate" means the rate of interest per annum publicly announced
from time to time by The Chase Manhattan Bank as its prime rate in effect at its
principal office in New York City.  Each change in the Prime Rate shall be
effective from and including the date such change is publicly announced as being
effective.

          "Pro Rata Share" means, for any Lender, the Commitment of such Lender
divided by the aggregate of the Commitments of all Lenders.

          "PUHCA" means the Public Utility Holding Company Act of 1935 and all
rules and regulations adopted thereunder.

          "Reciprocal Sharing Agreement" means the Colstrip Units 3 and 4
Generating Project Reciprocal Sharing Agreement, dated as of December 17, 1999,
between the Borrower and MPC.

          "Register" has the meaning set forth in Section 9.04.

          "Related Parties" means, with respect to any specified Person, such
Person's Affiliates and the respective directors, officers, employees, agents
and advisors of such Person and such Person's Affiliates.

          "Required Lenders" means, at any time, Lenders having Exposures and
unused Commitments representing more than 50% of the sum of the total Exposures
and unused Commitments at such time.

          "Restricted Investment" means any Investment other than a Permitted
Investment.

          "Restricted Payment" means:

          (a) the declaration or payment of any dividend or the making any other
payment or distribution on account of the Borrower's or any of its Core
Subsidiaries' Equity Interests (including any payment in connection with any
merger or consolidation involving the Borrower or any of its Core Subsidiaries)
or to the direct or indirect holders of the Borrower's or any of its Core
Subsidiaries' Equity Interests in their capacity as such (provided that the
payment of dividends or distributions payable in Equity Interests of the
Borrower or dividends or distributions to the Borrower or its Core Subsidiaries
shall not be deemed to be Restricted Payments);

                                       20
<PAGE>

          (b) the purchase, redemption or other acquisition or retirement for
value (including in connection with any merger or consolidation involving the
Borrower) of any Equity Interests in the Borrower or any of its Core
Subsidiaries to the extent that such payment is received by a Person other than
the Borrower or a Core Subsidiary;

          (c) the making of any payment on or with respect to, or the purchase,
redemption, defeasance or other acquisition or retirement for value of any
Subordinated Indebtedness of the Borrower;

          (d) the making of any Restricted Investment; or

          (e) the designation of a Core Subsidiary as an Additional Subsidiary
(the Restricted Payment made upon such a designation to be determined as the
fair market value of the Investments made in such Core Subsidiary by the
Borrower or any of its Core Subsidiaries).

          "Rosebud Coal Mine" means a large surface coal mining operation owned
and operated by Western Energy Company located in Rosebud County in southeastern
Montana.

          "Significant Lease Default" with respect to any Lease, has the meaning
given to such term in such Lease.

          "S&P" means Standard & Poor's Ratings Group.

          "Statutory Reserve Rate" means a fraction (expressed as a decimal),
the numerator of which is the number one and the denominator of which is the
number one minus the aggregate of the maximum reserve percentages (including any
marginal, special, emergency or supplemental reserves) expressed as a decimal
established by the Board to which the Administrative Agent is subject (a) with
respect to the Base CD Rate, for new negotiable nonpersonal time deposits in
dollars of over $100,000 with maturities approximately equal to three months,
and (b) with respect to the Adjusted LIBO Rate, for eurocurrency funding
(currently referred to as "Eurocurrency Liabilities" in Regulation D of the
Board).  Such reserve percentages shall include those imposed pursuant to such
Regulation D.  Eurodollar Loans shall be deemed to constitute eurocurrency
funding and to be subject to such reserve requirements without benefit of or
credit for proration, exemptions or offsets that may be available from time to
time to any Lender under such Regulation D or any comparable regulation.  The
Statutory Reserve Rate shall be adjusted automatically on and as of the
effective date of any change in any reserve percentage.

          "Subordinated Indebtedness" means Indebtedness that:

          (a) is expressly subordinated to the Borrower's payment obligations
under this Agreement on terms substantially similar to the subordination terms
attached as Schedule 1.01 to this Agreement,
            -------------

          (b) with respect to Subordinated Indebtedness issued to Affiliates of
the Borrower, is not required, in any contingency, to be redeemed or
repurchased, and

                                       21
<PAGE>

          (c) with respect to Indebtedness issued to Persons that are not
Affiliates of the Borrower, is otherwise satisfactory to the Required Lenders.

          "subsidiary" means, with respect to any Person (the "parent") at any
date, any corporation, limited liability company, partnership, association or
other entity the accounts of which would be consolidated with those of the
parent in the parent's consolidated financial statements if such financial
statements were prepared in accordance with GAAP as of such date, as well as any
other corporation, limited liability company, partnership, association or other
entity (a) of which securities or other ownership interests representing more
than 50% of the equity or more than 50% of the ordinary voting power or, in the
case of a partnership, more than 50% of the general partnership interests are,
as of such date, owned, controlled or held, or (b) that is, as of such date,
otherwise Controlled, by the parent or one or more subsidiaries of the parent or
by the parent and one or more subsidiaries of the parent.

          "Subsidiary" means any subsidiary of the Borrower.

          "Subsidiary Guarantee Agreement" means an agreement substantially in
the form of Exhibit B hereto to be executed by each of the Core Subsidiaries in
            ---------
favor of the Lenders.

          "Syndication Agent" means The Bank of Nova Scotia, in its capacity as
syndication agent.

          "Taxes" means any and all present or future taxes, levies, imposts,
duties, deductions, charges or withholdings imposed by any Governmental
Authority.

          "Three-Month Secondary CD Rate" means, for any day, the secondary
market rate for three-month certificates of deposit reported as being in effect
on such day (or, if such day is not a Business Day, the next preceding Business
Day) by the Board through the public information telephone line of the Federal
Reserve Bank of New York (which rate will, under the current practices of the
Board, be published in Federal Reserve Statistical Release H.15(519) during the
week following such day) or, if such rate is not so reported on such day or such
next preceding Business Day, the average of the secondary market quotations for
three-month certificates of deposit of major money center banks in New York City
received at approximately 10:00 a.m., New York City time, on such day (or, if
such day is not a Business Day, on the next preceding Business Day) by the
Administrative Agent from three negotiable certificate of deposit dealers of
recognized standing selected by it.

          "Total Capitalization" means, on any date of determination, with
respect to the Borrower and its Core Subsidiaries, the sum, without duplication,
of (a) total common stock equity or analogous ownership interests of such
Person, (b) preferred stock and preferred securities of such Person, (c)
additional paid in capital or analogous interests of such Person, (d) retained
earnings of such person and (e) the aggregate principal amount of Indebtedness
of such Persons determined on a consolidated basis in accordance with GAAP then
outstanding.

          "Transactions" means the execution, delivery and performance by each
Loan Party of the Loan Documents to which it is to be a party, the borrowing of
Loans, the use of the proceeds thereof and the issuance of Letters of Credit
hereunder.

                                       22
<PAGE>

          "Type," when used in reference to any Loan or Borrowing, refers to
whether the rate of interest on such Loan, or on the Loans comprising such
Borrowing, is determined by reference to the Adjusted LIBO Rate or the Alternate
Base Rate.

          "Wholesale Transition Service Agreements" means, collectively, (i) the
Colstrip Unit 3 Wholesale Transition Service Agreement, dated as of December 17,
1999, between the Borrower and MPC, and (ii) the Non-Colstrip Unit 3 Wholesale
Transition Service Agreement, dated as of December 17, 1999, between the
Borrower and MPC.

          "Withdrawal Liability" means liability to a Multiemployer Plan as a
result of a complete or partial withdrawal from such Multiemployer Plan, as such
terms are defined in Part I of Subtitle E of Title IV of ERISA.

          SECTION 1.02.  Classification of Loans and Borrowings. For purposes of
                         --------------------------------------
this Agreement, Loans may be classified and referred to by Type (e.g., a
"Eurodollar Loan"). Borrowings also may be classified and referred to by Type
(e.g., a "Eurodollar Borrowing").

          SECTION 1.03.  Terms Generally. The definitions of terms herein
                         ---------------
equality herein shall apply equally to the singular and plural forms of the
terms defined. Whenever the context may require, any pronoun shall include the
corresponding masculine, feminine and neuter forms. The words "include,"
"includes" and "including" shall be deemed to be followed by the phrase "without
limitation." The word "will" shall be construed to have the same meaning and
effect as the word "shall." Unless the context requires otherwise (a) any
definition of or reference to any agreement, instrument or other document herein
shall be construed as referring to such agreement, instrument or other document
as from time to time amended, supplemented or otherwise modified (subject to any
restrictions on such amendments, supplements or modifications set forth herein),
(b) any reference herein to any Person shall be construed to include such
Person's successors and assigns, (c) the words "herein," "hereof" and
"hereunder," and words of similar import, shall be construed to refer to this
Agreement in its entirety and not to any particular provision hereof, (d) all
references herein to Articles, Sections, Exhibits and Schedules shall be
construed to refer to Articles and Sections of, and Exhibits and Schedules to,
this Agreement and (e) the words "asset" and "property" shall be construed to
have the same meaning and effect and to refer to any and all tangible and
intangible assets and properties, including cash, securities, accounts and
contract rights.

          SECTION 1.04.  Accounting Terms; GAAP. Except as otherwise expressly
                         ----------------------
provided herein, all terms of an accounting or financial nature shall be
construed in accordance with GAAP, as in effect from time to time; provided
that, if the Borrower notifies the Administrative Agent that the Borrower
requests an amendment to any provision hereof to eliminate the effect of any
change occurring after the Closing Date in GAAP or in the application thereof on
the operation of such provision (or if the Administrative Agent notifies the
Borrower that the Required Lenders request an amendment to any provision hereof
for such purpose), regardless of whether any such notice is given before or
after such change in GAAP or in the application thereof, then such provision
shall be interpreted on the basis of GAAP as in effect and applied immediately
before such change shall have become effective until such notice shall have been
withdrawn or such provision amended in accordance herewith.

                                       23
<PAGE>

                                   ARTICLE II

                                  The Credits
                                  -----------

          SECTION 2.01.  Commitments. Subject to the terms and conditions set
                         -----------
forth herein, (i) the Issuing Bank agrees to issue Letters of Credit in
accordance with Section 2.02, (ii) each Lender agrees to acquire participations
                ------------
in such Letters of Credit in accordance with Section 2.02(d) and (iii) each
                                             ---------------
Lender agrees to make Loans to the Borrower in accordance with Section 2.02(e),
                                                               ---------------
in each case, from time to time during the Availability Period in an aggregate
stated amount or principal amount that will not result in any Lender's Exposure
exceeding such Lender's Commitment. Except upon the Maturity Date, the
termination of the Commitments as provided herein or the reduction of the
Commitments pursuant to Section 2.06, the aggregate Commitment of the Lenders
                        ------------
shall not be reduced upon payment of any LC Disbursement or upon the repayment
or prepayments of any Loan.

          SECTION 2.02.  Letters of Credit
                         -----------------

          (a)    General. Subject to the terms and conditions set forth herein,
                 -------
the Borrower may request the issuance of Letters of Credit for its own account,
in a form reasonably acceptable to the Administrative Agent and the Issuing
Bank, at any time and from time to time during the Availability Period. In the
event of any inconsistency between the terms and conditions of this Agreement
and the terms and conditions of any form of letter of credit application or
other agreement submitted by the Borrower to, or entered into by the Borrower
with, the Issuing Bank relating to any Letter of Credit, the terms and
conditions of this Agreement shall control.

          (b)    Notice of Issuance, Amendment, Renewal, Extension; Certain
                 ----------------------------------------------------------
Conditions.  To request the issuance of a Letter of Credit (or the amendment,
----------
renewal or extension of an outstanding Letter of Credit), the Borrower shall
hand deliver or telecopy (or transmit by electronic communication, if
arrangements for doing so have been approved by the Issuing Bank) to the Issuing
Bank and the Administrative Agent (reasonably in advance of the requested date
of issuance, amendment, renewal or extension) a written Letter of Credit Request
substantially in the form of Exhibit D signed by the Borrower requesting the
                             ---------
issuance of a Letter of Credit, or identifying the Letter of Credit to be
amended, renewed or extended, and specifying the date of issuance, amendment,
renewal or extension (which shall be a Business Day), the date on which such
Letter of Credit is to expire (which shall comply with paragraph (c) of this
Section), the amount of such Letter of Credit, the name and address of the
beneficiary thereof and such other information as shall be necessary to prepare,
amend, renew or extend such Letter of Credit.  If requested by the Issuing Bank,
the Borrower also shall submit a letter of credit application on the Issuing
Bank's standard form in connection with any Letter of Credit Request.  A Letter
of Credit shall be issued, amended, renewed or extended only if (and upon
issuance, amendment, renewal or extension of each Letter of Credit the Borrower
shall be deemed to represent and warrant that), after giving effect to such
issuance, amendment, renewal or extension the total Exposures shall not exceed
the total Commitments.

          (c)    Expiration Date. Each Letter of Credit shall expire at or prior
                 ---------------
to the close of business on the date that is five Business Days prior to the
Maturity Date.

                                       24
<PAGE>

          (d)    Participations.  By the issuance of a Letter of Credit (or an
                 --------------
amendment to a Letter of Credit increasing the amount thereof) and without any
further action on the part of the Issuing Bank or the Lenders, the Issuing Bank
hereby grants to each Lender, and each Lender hereby acquires from the Issuing
Bank, a participation in such Letter of Credit equal to such Lender's Applicable
Percentage of the aggregate amount available to be drawn under such Letter of
Credit.  In consideration and in furtherance of the foregoing, each Lender
hereby absolutely and unconditionally agrees to pay to the Administrative Agent,
for the account of the Issuing Bank, such Lender's Applicable Percentage of each
LC Disbursement made by the Issuing Bank and not reimbursed by the Borrower on
the date due as provided in paragraph (e) of this Section, or of any
reimbursement payment required to be refunded to the Borrower for any reason.
Each Lender acknowledges and agrees that its obligation to acquire
participations pursuant to this paragraph in respect of Letters of Credit is
absolute and unconditional and shall not be affected by any circumstance
whatsoever, including any amendment, renewal or extension of any Letter of
Credit or the occurrence and continuance of a Default or reduction or
termination of the Commitments, and that each such payment shall be made without
any offset, abatement, withholding or reduction whatsoever.

          (e)    Reimbursement. If the Issuing Bank shall make any LC
                 -------------
Disbursement in respect of a Letter of Credit, the Borrower shall reimburse such
LC Disbursement by paying to the Administrative Agent an amount equal to such LC
Disbursement not later than 12:00 noon, New York City time, on the date that
such LC Disbursement is made, if the Borrower shall have received notice of such
LC Disbursement prior to 10:00 a.m., New York City time, on such date, or, if
such notice has not been received by the Borrower prior to such time on such
date, then not later than 12:00 noon, New York City time, on:

             (i)  the Business Day that the Borrower receives such notice, if
     such notice is received prior to 10:00 a.m., New York City time, on the day
     of receipt, or

             (ii) the Business Day immediately following the day that the
     Borrower receives such notice, if such notice is not received prior to such
     time on the day of receipt;

provided that, if such LC Disbursement is not less than $1,000,000, the Borrower
may, subject to the conditions to borrowing set forth herein, request in
accordance with Section 2.03 that such reimbursement obligation be financed with
                ------------
an ABR Borrowing in an equivalent amount and, to the extent so financed, the
Borrower's obligation to pay such reimbursement obligation shall be discharged
and replaced by the resulting ABR Borrowing.  If the Borrower fails to pay any
portion of a reimbursement obligation when any such payment is due and no
Borrowing is made in satisfaction of any such reimbursement obligation (as a
result of the Borrower's failure to request a Borrowing, the Borrower's failure
to satisfy the conditions to such Borrowing contain in Section 4.02 or
                                                       ------------
otherwise), then the Administrative Agent shall notify each Lender of the
applicable LC Disbursement, the payment then due from the Borrower in respect
thereof and such Lender's Applicable Percentage thereof.  Promptly following
receipt of such notice, each Lender shall pay to the Administrative Agent its
Applicable Percentage of the payment then due from the Borrower, in the same
manner as provided in Section 2.05 with respect to Loans made by such Lender
                      ------------
(and Section 2.05 shall apply, mutatis mutandis, to the payment obligations of
     ------------
the Lenders), and the Administrative Agent shall promptly pay to the Issuing
Bank the amounts

                                       25
<PAGE>

so received by it from the Lenders. Promptly following receipt by the
Administrative Agent of any payment from the Borrower pursuant to this
paragraph, the Administrative Agent shall distribute such payment to the Issuing
Bank or, to the extent that Lenders have made payments pursuant to this
paragraph to reimburse the Issuing Bank, then to such Lenders and the Issuing
Bank as their interests may appear. Any payment made by a Lender pursuant to
this paragraph to reimburse the Issuing Bank for any LC Disbursement (other than
the funding of ABR Loans as contemplated above) shall not constitute a Loan and
shall not relieve the Borrower of its obligation to reimburse such LC
Disbursement.

          (f)    Obligations Absolute. The Borrower's obligation to reimburse LC
                 --------------------
Disbursements as provided in paragraph (e) of this Section shall be absolute,
unconditional and irrevocable, and shall be performed strictly in accordance
with the terms of this Agreement under any and all circumstances whatsoever and
irrespective of:

              (i)   any lack of validity or enforceability of any Letter of
     Credit or this Agreement, or any term or provision therein,

              (ii)  any draft or other document presented under a Letter of
     Credit proving to be forged, fraudulent or invalid in any respect or any
     statement therein being untrue or inaccurate in any respect,

              (iii) payment by the Issuing Bank under a Letter of Credit against
     presentation of a draft or other document that does not comply with the
     terms of such Letter of Credit, or

              (iv)  any other event or circumstance whatsoever, whether or not
     similar to any of the foregoing, that might, but for the provisions of this
     Section, constitute a legal or equitable discharge of, or provide a right
     of setoff against, the Borrower's obligations hereunder.

Neither the Administrative Agent, nor the Lenders, the Issuing Bank or any of
their Related Parties, shall have any liability or responsibility by reason of
or in connection with the issuance or transfer of any Letter of Credit or any
payment or failure to make any payment thereunder (irrespective of any of the
circumstances referred to in the preceding sentence), or any error, omission,
interruption, loss or delay in transmission or delivery of any draft, notice or
other communication under or relating to any Letter of Credit (including any
document required to make a drawing thereunder), any error in interpretation of
technical terms or any consequence arising from causes beyond the control of the
Issuing Bank; provided that the foregoing shall not be construed to excuse the
Issuing Bank from liability to the Borrower to the extent of any direct damages
(as opposed to consequential damages, claims in respect of which are hereby
waived by the Borrower to the extent permitted by applicable law) suffered by
the Borrower that are caused by the Issuing Bank's failure to exercise care when
determining whether drafts and other documents presented under a Letter of
Credit comply with the terms thereof.  The parties hereto expressly agree that,
in the absence of gross negligence or willful misconduct on the part of the
Issuing Bank (as finally determined by a court of competent jurisdiction), the
Issuing Bank shall be deemed to have exercised care in each such determination.
In furtherance of the foregoing and without limiting the generality thereof, the
parties agree that, with respect to documents

                                       26
<PAGE>

presented which appear on their face to be in substantial compliance with the
terms of a Letter of Credit, the Issuing Bank may, in its sole discretion,
either accept and make payment upon such documents without responsibility for
further investigation, regardless of any notice or information to the contrary,
or refuse to accept and make payment upon such documents if such documents are
not in strict compliance with the terms of such Letter of Credit.

          (g)    Disbursement Procedures. The Issuing Bank shall, promptly
                 -----------------------
following its receipt thereof, examine all documents purporting to represent a
demand for payment under a Letter of Credit. The Issuing Bank shall promptly
notify the Administrative Agent and the Borrower by telephone (confirmed by
telecopy) of such demand for payment and whether the Issuing Bank has made or
will make an LC Disbursement thereunder; provided that any failure to give or
delay in giving such notice shall not relieve the Borrower of its obligation to
reimburse the Issuing Bank and the Lenders with respect to any such LC
Disbursement.

          (h)    Interim Interest.  If the Issuing Bank shall make any LC
                 ----------------
Disbursement, then, unless the Borrower shall reimburse such LC Disbursement in
full on the date such LC Disbursement is made, the unpaid amount thereof shall
bear interest, for each day from and including the date such LC Disbursement is
made to but excluding the date that the Borrower reimburses such LC
Disbursement, at the rate per annum then applicable to ABR Loans; provided that,
if the Borrower fails to reimburse such LC Disbursement when due pursuant to
paragraph (e) of this Section, then Section 2.10(c) shall apply.  Interest
                                    ---------------
accrued pursuant to this paragraph shall be for the account of the Issuing Bank,
except that interest accrued on and after the date of payment by any Lender
pursuant to paragraph (e) of this Section to reimburse the Issuing Bank shall be
for the account of such Lender to the extent of such payment.

          (i)    Replacement of the Issuing Bank. The Issuing Bank may be
                 -------------------------------
replaced at any time by written agreement among the Borrower, the Administrative
Agent, the replaced Issuing Bank and the successor Issuing Bank. The
Administrative Agent shall notify the Lenders of any such replacement of the
Issuing Bank. At the time any such replacement shall become effective, the
Borrower shall pay all unpaid fees accrued for the account of the replaced
Issuing Bank pursuant to Section 2.09(b). From and after the effective date of
                         ---------------
any such replacement, (i) the successor Issuing Bank shall have all the rights
and obligations of the Issuing Bank under this Agreement with respect to Letters
of Credit to be issued thereafter and (ii) references herein to the term
"Issuing Bank" shall be deemed to refer to such successor or to any previous
Issuing Bank, or to such successor and all previous Issuing Banks, as the
context shall require. After the replacement of an Issuing Bank hereunder, the
replaced Issuing Bank shall remain a party hereto and shall continue to have all
the rights and obligations of an Issuing Bank under this Agreement with respect
to Letters of Credit issued by it prior to such replacement, but shall not be
required to issue additional Letters of Credit.

          (j)    Cash Collateralization. If any Event of Default shall occur and
                 ----------------------
be continuing, on the Business Day that the Borrower receives notice from the
Administrative Agent or the Required Lenders demanding the deposit of cash
collateral pursuant to this paragraph, the Borrower shall deposit in an account
with the Administrative Agent, in the name of the Administrative Agent and for
the benefit of the Lenders, an amount in cash equal to the LC Exposure as of
such date plus any accrued and unpaid interest thereon; provided that the
obligation to deposit such cash collateral shall become effective immediately,
and such deposit

                                       27
<PAGE>

shall become immediately due and payable, without demand or other notice of any
kind, upon the occurrence of any Event of Default with respect to the Borrower
described in clause (h) or (i) of Article VII. The Borrower also shall deposit
                                  -----------
cash collateral pursuant to this paragraph as and to the extent required by
Section 2.08(b). Each such deposit shall be held by the Administrative Agent as
---------------
collateral for the payment and performance of the obligations of the Borrower
under this Agreement. The Administrative Agent shall have exclusive dominion and
control, including the exclusive right of withdrawal, over such account. Other
than any interest earned on the investment of such deposits, which investments
shall be made in Permitted Investments by the Administrative Agent and at the
Borrower's risk and expense, such deposits shall not bear interest. Interest or
profits, if any, on such investments shall accumulate in such account. Moneys in
such account shall be applied by the Administrative Agent to reimburse the
Issuing Bank for LC Disbursements for which it has not been reimbursed and, to
the extent not so applied, shall be held for the satisfaction of the
reimbursement obligations of the Borrower for the LC Exposure at such time or,
if the maturity of the Loans has been accelerated, be applied to satisfy other
obligations of the Borrower under this Agreement. If the Borrower is required to
provide an amount of cash collateral hereunder as a result of the occurrence of
an Event of Default, such amount (to the extent not applied as aforesaid) plus
any interest earned from the investment of such amount shall be returned to the
Borrower within three Business Days after all Events of Default have been cured
or waived. If the Borrower is required to provide an amount of cash collateral
hereunder pursuant to Section 2.08(b), such amount (to the extent not applied as
                      ---------------
aforesaid) plus any interest earned from the investment of such amount shall be
returned to the Borrower as and to the extent that, after giving effect to such
return, the Borrower would remain in compliance with Section 2.08(b) and no
                                                     ---------------
Default shall have occurred and be continuing.

          SECTION 2.03.  Loans and Borrowings
                         --------------------

          (a)    Each initial Loan shall be an ABR Borrowing made in accordance
with the procedures set forth in Section 2.02(e). To request a Borrowing, the
                                 ---------------
Borrower shall notify the Administrative Agent of such request by telephone not
later than 10:00 a.m., New York City time, on the date of the proposed
Borrowing.  Each such telephonic Borrowing Request shall be irrevocable and
shall be confirmed promptly by hand delivery or telecopy to the Administrative
Agent of a written Borrowing Request substantially in the form of Exhibit E and
                                                                  ---------
signed by the Borrower.  Thereafter, the Borrower may elect to convert such
Borrowing to a different Type or to continue such Borrowing and, in the case of
a Eurodollar Borrowing, may elect Interest Periods therefor, all as provided in
this Section 2.04.  Each Loan shall be made as part of a Borrowing consisting of
     ------------
Loans of the same Type made by the Lenders ratably in accordance with their
respective Commitments.  The failure of any Lender to make any Loan required to
be made by it shall not relieve any other Lender of its obligations hereunder;
provided that the Commitments of the Lenders are several and no Lender shall be
responsible for any other Lender's failure to make Loans as required.

          (b)    Subject to Section 2.11, each Borrowing shall be comprised
                            ------------
entirely of ABR Loans or Eurodollar Loans as the Borrower may request in
accordance with Section 2.04. Each Lender at its option may make any Eurodollar
                ------------
Loan by causing any domestic or foreign branch or Affiliate of such Lender to
make such Loan; provided that any exercise of such option shall not affect the
obligation of the Borrower to repay such Loan in accordance with the terms of
this Agreement.

                                       28
<PAGE>

          SECTION 2.04.  Interest Election Requests
                         --------------------------

          (a)    The Borrower may elect different options with respect to
different portions of the affected Borrowing, in which case each such portion
shall be allocated ratably among the Lenders holding the Loans comprising such
Borrowing, and the Loans comprising each such portion shall be considered a
separate Borrowing.

          (b)    To make an election pursuant to this Section, the Borrower
shall notify the Administrative Agent of such request by telephone (1) in the
case of the continuation of or conversion to a Eurodollar Borrowing, not later
than 11:00 a.m., New York City time, three Business Days before the date of the
proposed Borrowing or (2) in the case of the continuation of or conversion to an
ABR Borrowing, not later than 11:00 a.m., New York City time, one Business Day
before the date of the proposed conversion or continuation. Each such telephonic
Interest Election Request shall be irrevocable and shall be confirmed promptly
by hand delivery or telecopy to the Administrative Agent of a written Interest
Election Request substantially in the form of Exhibit F and signed by the
                                              ---------
Borrower. Each telephonic and written Interest Election Request shall specify
the following information:

              (i)   the Borrowing to which such Interest Election Request
     applies and, if different options are being elected with respect to
     different portions thereof, the portions thereof to be allocated to each
     resulting Borrowing (in which case the information to be specified pursuant
     to clauses (iii) and (iv) below shall be specified for each resulting
     Borrowing);

              (ii)  the effective date of the election made pursuant to such
     Interest Election Request, which shall be a Business Day;

              (iii) whether the resulting Borrowing is to be an ABR Borrowing or
     a Eurodollar Borrowing; and

              (iv)  if the resulting Borrowing is a Eurodollar Borrowing, the
     Interest Period to be applicable thereto after giving effect to such
     election, which shall be a period contemplated by the definition of the
     term "Interest Period."

If any such Interest Election Request requests a Eurodollar Borrowing but does
not specify an Interest Period, then the Borrower shall be deemed to have
selected an Interest Period of one month's duration.

          (c)    Promptly following receipt of an Interest Election Request in
accordance with this Section, the Administrative Agent shall advise each Lender
of the details thereof and of such Lender's portion of each resulting Borrowing.

          (d)    At the commencement of each Interest Period for any Eurodollar
Borrowing, such Borrowing shall be in an aggregate amount that is an integral
multiple of $1,000,000 and not less than $5,000,000.  At the time of any
conversion to an ABR Borrowing, such Borrowing shall be in an aggregate amount
that is an integral multiple of $1,000,000 and not less than $5,000,000.
Borrowings of more than one Type may be outstanding at the same

                                       29
<PAGE>

time; provided that there shall not at any time be more than a total of ten
Eurodollar Borrowings outstanding.

          (e)    Notwithstanding any other provision of this Agreement, the
Borrower shall not be entitled to request, or to elect to convert or continue,
any Borrowing if the Interest Period requested with respect thereto would end
after the Maturity Date.

          (f)    If the Borrower fails to deliver a timely Interest Election
Request with respect to a Eurodollar Borrowing prior to the end of the Interest
Period applicable thereto, then, unless such Borrowing is repaid as provided
herein, at the end of such Interest Period such Borrowing shall be converted to
an ABR Borrowing. Notwithstanding any contrary provision hereof, if an Event of
Default has occurred and is continuing and the Administrative Agent, at the
request of the Required Lenders, so notifies the Borrower, then, so long as an
Event of Default is continuing (i) no outstanding Borrowing may be converted to
or continued as a Eurodollar Borrowing and (ii) unless repaid, each Eurodollar
Borrowing shall be converted to an ABR Borrowing at the end of the Interest
Period applicable thereto.

          SECTION 2.05.  Funding of Borrowings
                         ---------------------

          (a)    Each Lender shall make each Loan to be made by it hereunder on
the proposed date thereof by wire transfer of immediately available funds by
12:00 noon, New York City time, to the account of the Administrative Agent most
recently designated by it for such purpose by notice to the Lenders. The
Administrative Agent will remit ABR Loans made to finance the reimbursement of
an LC Disbursement as provided in Section 2.02(e) to the Issuing Bank.
                                  ---------------

          (b)    Unless the Administrative Agent shall have received notice from
a Lender prior to the proposed date of any Borrowing that such Lender will not
make available to the Administrative Agent such Lender's share of such
Borrowing, the Administrative Agent may assume that such Lender has made such
share available on such date in accordance with paragraph (a) of this Section
and may, in reliance upon such assumption, make available to the Borrower a
corresponding amount. In such event, if a Lender has not in fact made its share
of the applicable Borrowing available to the Administrative Agent, then the
applicable Lender and the Borrower severally agree to pay to the Administrative
Agent forthwith on demand such corresponding amount with interest thereon, for
each day from and including the date such amount is made available to the
Borrower to but excluding the date of payment to the Administrative Agent, at
(i) in the case of such Lender, the greater of the Federal Funds Effective Rate
and a rate determined by the Administrative Agent in accordance with banking
industry rules on interbank compensation or (ii) in the case of the Borrower,
the interest rate then applicable to ABR Loans. If such Lender pays such amount
to the Administrative Agent, then such amount shall constitute such Lender's
Loan included in such Borrowing.

          SECTION 2.06.  Termination and Reduction of Commitments
                         ----------------------------------------

          (a)    Unless previously terminated, the Commitments shall terminate
on the Maturity Date.

                                       30
<PAGE>

     (b)    The Borrower may at any time terminate, or from time to time reduce,
in whole or in part, the Commitments; provided that (i) each partial reduction
of the Commitments shall be in an amount that is an integral multiple of
$1,000,000 and not less than $5,000,000, and (ii) the Borrower shall not
terminate or reduce the Commitments if, after giving effect to any concurrent
prepayment of the Loans in accordance with Section 2.08, the Exposure would
                                           ------------
exceed the total Commitments.

     (c)    The Borrower shall notify the Administrative Agent of any election
to terminate or reduce the Commitments under paragraph (b) of this Section at
least five Business Days prior to the effective date of such termination or
reduction, specifying such election and the effective date thereof.  Promptly
following receipt of any notice, the Administrative Agent shall advise the
Lenders of the contents thereof.  Each notice delivered by the Borrower pursuant
to this Section shall be irrevocable; provided that a notice of termination of
the Commitments delivered by the Borrower may state that such notice is
conditioned upon the effectiveness of other credit facilities, in which case
such notice may be revoked by the Borrower (by notice to the Administrative
Agent on or prior to the specified effective date) if such condition is not
satisfied.  Any termination or reduction of the Commitments shall be permanent.
Each reduction of the Commitments shall be made ratably among the Lenders in
accordance with their respective Commitments.

     SECTION 2.07.  Repayment of Loans; Evidence of Debt
                    ------------------------------------

     (a)    The Borrower hereby unconditionally promises to pay to the
Administrative Agent for the account of each Lender the then unpaid principal
amount of each Loan on the Maturity Date.

     (b)    Each Lender shall maintain in accordance with its usual practice an
account or accounts evidencing the indebtedness of the Borrower to such Lender
resulting from each Loan made by such Lender, including the amounts of principal
and interest payable and paid to such Lender from time to time hereunder.

     (c)    The Administrative Agent shall maintain accounts in which it shall
record (i) the amount of each Loan made hereunder, the Type thereof and the
Interest Period applicable thereto, (ii) the amount of any principal or interest
due and payable or to become due and payable from the Borrower to each Lender
hereunder and (iii) the amount of any sum received by the Administrative Agent
hereunder for the account of the Lenders and each Lender's share thereof.

     (d)    The entries made in the accounts maintained pursuant to paragraph
(b) or (c) of this Section shall be prima facie evidence of the existence and
amounts of the obligations recorded therein; provided that the failure of any
Lender or the Administrative Agent to maintain such accounts or any error
therein shall not in any manner affect the obligation of the Borrower to repay
the Loans in accordance with the terms of this Agreement.

     (e)    Any Lender may request that Loans made by it be evidenced by a
promissory note.  In such event, the Borrower shall prepare, execute and deliver
to such Lender a promissory note payable to the order of such Lender (or, if
requested by such Lender, to such

                                       31
<PAGE>

Lender and its registered assigns) and in a form approved by the Administrative
Agent. Thereafter, the Loans evidenced by such promissory note and interest
thereon shall at all times (including after assignment pursuant to Section 9.04)
                                                                   ------------
be represented by one or more promissory notes in such form payable to the order
of the payee named therein (or, if such promissory note is a registered note, to
such payee and its registered assigns).

     SECTION 2.08.  Prepayment of Loans
                    -------------------

     (a)  The Borrower shall have the right at any time and from time to time
to prepay any Loan in whole or in part, subject to the requirements of this
Section.

     (b)  In the event and on each occasion that the Exposure exceeds the
total Commitments, (1) the Borrower shall prepay Loans in an aggregate amount
equal to such excess or, (2) if no such Loans are outstanding, deposit cash
collateral in an amount equal to (A) such excess LC Exposure plus (B) an amount
to cover the facility fee in respect of such excess LC Exposure of the Lenders,
in an account with the Administrative Agent pursuant to Section 2.02(j).
                                                        ---------------

     (c)  The Borrower shall notify the Administrative Agent by telephone
(confirmed by telecopy) of any prepayment hereunder (i) in the case of
prepayment of a Eurodollar Borrowing, not later than 11:00 a.m., New York City
time, three Business Days before the date of prepayment and (ii) in the case of
prepayment of an ABR Borrowing, not later than 11:00 a.m., New York City time,
one Business Day before the date of prepayment. Each such notice shall be
irrevocable and shall specify the prepayment date, the principal amount of each
Borrowing or portion thereof to be prepaid and, in the case of a mandatory
prepayment, a reasonably detailed calculation of the amount of such prepayment;
provided that, if a notice of optional prepayment is given in connection with a
conditional notice of termination of the Commitments as contemplated by Section
                                                                        -------
2.06, then such notice of prepayment may be revoked if such notice of
----
termination is revoked in accordance with Section 2.06.  Promptly following
                                          ------------
receipt of any such notice, the Administrative Agent shall advise the Lenders of
the contents thereof. Each partial prepayment of any Borrowing shall be in an
amount that would be permitted in the case of an advance of a Borrowing of the
same Type as provided in Section 2.03, except as necessary to apply fully the
                         ------------
required amount of a mandatory prepayment. Each prepayment of a Borrowing shall
be applied ratably to the Loans included in the prepaid Borrowing.  Prepayments
shall be accompanied by accrued interest to the extent required by Section 2.10.
                                                                   ------------

     SECTION 2.09.  Fees
                    ----

     (a)  The Borrower agrees to pay to the Administrative Agent for the account
of each Lender a facility fee, which shall accrue at the Applicable Rate on the
daily amount of each Commitment of such Lender (whether used or unused) during
the period from and including the Closing Date to but excluding the date on
which such Commitment terminates; provided that, if such Lender continues to
have any Exposure after its Commitment terminates, then such facility fee shall
continue to accrue on the daily amount of such Lender's Exposure from and
including the date on which its Commitment terminates to but excluding the date
on which such Lender ceases to have any Exposure. Accrued facility fees shall be
payable in arrears on the last day of

                                       32
<PAGE>

March, June, September and December of each year and on the date on which the
Commitments terminate, commencing on the first such date to occur after the
Closing Date; provided that any facility fees accruing after the date on which
the Commitments terminate shall be payable on demand. All facility fees shall be
computed on the basis of a year of 360 days and shall be payable for the actual
number of days elapsed (including the first day but excluding the last day). If
a Status is applied retroactively in accordance with clause (b) of the proviso
to the last paragraph in the definition of Applicable Rate, the Borrower shall
pay to the Administrative Agent for the account of each Lender, within ten (10)
Business Days of the day on which the ratings are subsequently assigned by
Moody's and S&P as referred to in such clause (b), the additional amount of
facility fees due to such Lender as a result of such retroactive application.

          (b)     The Borrower agrees to pay:

               (i)  to the Administrative Agent for the account of each Lender a
     participation fee with respect to its participations in Letters of Credit,
     which shall accrue at the Applicable Rate on the average daily amount of
     such Lender's LC Exposure (excluding any portion thereof attributable to
     unreimbursed LC Disbursements) during the period from and including the
     first date on which such Lender has any LC Exposure to but excluding the
     date on which such Lender ceases to have any LC Exposure, and

               (ii) to the Issuing Bank a letter of credit fee as separately
     agreed between the Borrower and the Issuing Bank, as well as the Issuing
     Bank's standard fees with respect to the issuance, amendment, renewal or
     extension of any Letter of Credit or processing of drawings thereunder.

Participation fees accrued through and including the last day of March, June,
September and December of each year shall be payable on such last day,
commencing on the first such date to occur after the Closing Date; provided that
all such fees shall be payable on the date on which the Commitments terminate
and any such fees accruing after the date on which the Commitments terminate
shall be payable on demand. Any other fees payable to the Issuing Bank pursuant
to this paragraph shall be payable within 10 days after demand. All
participation fees shall be computed on the basis of a year of 360 days and
shall be payable for the actual number of days elapsed (including the first day
but excluding the last day).

          (c)   All fees payable hereunder shall be paid on the dates due, in
immediately available funds, to the Administrative Agent (or to the Issuing
Bank, in the case of fees payable to it) for distribution, in the case of
facility fees and participation fees, to the Lenders entitled thereto.  Fees
paid shall not be refundable under any circumstances.

          SECTION 2.10. Interest.
                        --------

          (a)   The Loans comprising each ABR Borrowing shall bear interest at
the Alternate Base Rate plus the Applicable Rate.

          (b)   The Loans comprising each Eurodollar Borrowing shall bear
interest in the case of a Eurodollar Loan, at the Adjusted LIBO Rate for the
Interest Period in effect for such Borrowing plus the Applicable Rate.

                                       33
<PAGE>

          (c)    Notwithstanding the foregoing, if any principal of or interest
on any Loan or any fee or other amount payable by the Borrower hereunder is not
paid when due, whether at stated maturity, upon acceleration or otherwise, such
overdue amount shall bear interest, after as well as before judgment, at a rate
per annum equal to (i) in the case of overdue principal of any Loan, 2% plus the
rate otherwise applicable to such Loan as provided in the preceding paragraphs
of this Section or (ii) in the case of any other amount, 2% plus the rate
applicable to ABR Revolving Loans as provided in paragraph (a) of this Section.

          (d)    Accrued interest on each Loan shall be payable in arrears on
each Interest Payment Date for such Loan; provided that:

               (i)   interest accrued pursuant to paragraph (c) of this Section
     shall be payable on demand,

               (ii)  in the event of any repayment or prepayment of any Loan
     (other than a prepayment of an ABR Loan prior to the end of the
     Availability Period), accrued interest on the principal amount repaid or
     prepaid shall be payable on the date of such repayment or prepayment,

               (iii) in the event of any conversion of any Eurodollar Loan prior
     to the end of the current Interest Period therefor, accrued interest on
     such Loan shall be payable on the effective date of such conversion, and

               (iv)  all accrued interest shall be payable upon termination of
     the Commitments.

          (e)    All interest hereunder shall be computed on the basis of a year
of 360 days, except that interest computed by reference to the Alternate Base
Rate at times when the Alternate Base Rate is based on the Prime Rate shall be
computed on the basis of a year of 365 days (or 366 days in a leap year), and in
each case shall be payable for the actual number of days elapsed (including the
first day but excluding the last day). The applicable Alternate Base Rate or
Adjusted LIBO Rate shall be determined by the Administrative Agent, and such
determination shall be conclusive absent manifest error.

          SECTION 2.11.  Alternate Rate of Interest. If prior to the
                         --------------------------
commencement of any Interest Period for Eurodollar Borrowing:

          (a) the Administrative Agent determines (which determination shall be
     conclusive absent manifest error) that adequate and reasonable means do not
     exist for ascertaining the Adjusted LIBO Rate for such Interest Period; or

          (b) the Administrative Agent is advised by the Required Lenders that
     the Adjusted LIBO Rate for such Interest Period will not adequately and
     fairly reflect the cost to such Lenders of making or maintaining their
     Loans included in such Borrowing for such Interest Period;

then the Administrative Agent shall give notice thereof to the Borrower and the
Lenders by telephone or telecopy as promptly as practicable thereafter and,
until the Administrative Agent

                                       34
<PAGE>

notifies the Borrower and the Lenders that the circumstances giving rise to such
notice no longer exist, any Interest Election Request that requests the
conversion of any Borrowing to, or continuation of any Borrowing as, a
Eurodollar Borrowing for such Interest Period shall be ineffective.

          SECTION 2.12.  Increased Costs.
                         ---------------

          (a)     If any Change in Law shall:

               (i)  impose, modify or deem applicable any reserve, special
     deposit or similar requirement against assets of, deposits with or for the
     account of, or credit extended by, any Lender (except any such reserve
     requirement reflected in the Adjusted LIBO Rate) or the Issuing Bank; or

               (ii) impose on any Lender or the Issuing Bank or the London
     interbank market any other condition affecting this Agreement or Eurodollar
     Loans made by such Lender or any Letter of Credit or participation therein;

and the result of any of the foregoing shall be to increase the cost to such
Lender of making or maintaining any Eurodollar Loan (or of maintaining its
obligation to make any such Loan) or to increase the cost to such Lender or the
Issuing Bank of participating in, issuing or maintaining any Letter of Credit or
to reduce the amount of any sum received or receivable by such Lender or the
Issuing Bank hereunder (whether of principal, interest or otherwise), then the
Borrower will pay to such Lender or the Issuing Bank, as the case may be, such
additional amount or amounts as will compensate such Lender or the Issuing Bank,
as the case may be, for such additional costs incurred or reduction suffered.

          (b)  If any Lender or the Issuing Bank determines that any Change in
Law regarding capital requirements has the effect of reducing the rate of return
on such Lender's or the Issuing Bank's capital or on the capital of such
Lender's or the Issuing Bank's holding company, if any, as a consequence of this
Agreement or the Loans made by, or participations in Letters of Credit held by,
such Lender, or the Letters of Credit issued by the Issuing Bank, to a level
below that which such Lender or the Issuing Bank or such Lender's or the Issuing
Bank's holding company could have achieved but for such Change in Law (taking
into consideration such Lender's or the Issuing Bank's policies and the policies
of such Lender's or the Issuing Bank's holding company with respect to capital
adequacy), then from time to time the Borrower will pay to such Lender or the
Issuing Bank, as the case may be, such additional amount or amounts as will
compensate such Lender or the Issuing Bank or such Lender's or the Issuing
Bank's holding company for any such reduction suffered.

          (c)  A certificate of a Lender or the Issuing Bank setting forth in
reasonable detail the amount or amounts (and the calculation thereof) necessary
to compensate such Lender or the Issuing Bank or its holding company, as the
case may be, as specified in paragraph (a) or (b) of this Section shall be
delivered to the Borrower and shall be conclusive absent manifest error. The
Borrower shall pay such Lender or the Issuing Bank, as the case may be, the
amount shown as due on any such certificate within 10 days after receipt
thereof.

                                       35
<PAGE>

     (d)    Failure or delay on the part of any Lender or the Issuing Bank to
demand compensation pursuant to this Section shall not constitute a waiver of
such Lender's or the Issuing Bank's right to demand such compensation; provided
that the Borrower shall not be required to compensate a Lender or the Issuing
Bank pursuant to this Section for any increased costs or reductions incurred
more than 180 days prior to the date that such Lender or the Issuing Bank, as
the case may be, notifies the Borrower of the Change in Law giving rise to such
increased costs or reductions and of such Lender's or the Issuing Bank's
intention to claim compensation therefor; provided further that, if the Change
in Law giving rise to such increased costs or reductions is retroactive, then
the 180-day period referred to above shall be extended to include the period of
retroactive effect thereof.

     SECTION 2.13.  Break Funding Payments. In the event of:
                    -----------------------

     (a)    the payment of any principal of any Eurodollar Loan other than on
the last day of an Interest Period applicable thereto (including as a result of
an Event of Default),

     (b)    the conversion of any Eurodollar Loan other than on the last day of
the Interest Period applicable thereto,

     (c)    the failure to borrow, convert, continue or prepay any Eurodollar
Loan on the date specified in any notice delivered pursuant hereto other than as
a result of an event described in Section 2.11(a) hereof (regardless of whether
                                  ---------------
such notice may be revoked under Section 2.08(c) and is revoked in accordance
                                 ---------------
therewith), or

     (d)    the assignment of any Eurodollar Loan other than on the last day of
the Interest Period applicable thereto as a result of a request by the Borrower
pursuant to Section 2.16,
            ------------

then, in any such event, the Borrower shall compensate each Lender for its loss,
cost and expense attributable to such event. In the case of a Eurodollar Loan,
such loss, cost or expense to any Lender shall be deemed to include an amount
determined by such Lender to be the excess, if any, of:

           (i) the amount of interest which would have accrued on the principal
     amount of such Loan had such event not occurred, at the Adjusted LIBO Rate
     that would have been applicable to such Loan, for the period from the date
     of such event to the last day of the then current Interest Period therefor
     (or, in the case of a failure to borrow, convert or continue, for the
     period that would have been the Interest Period for such Loan), over

           (ii) the amount of interest which would accrue on such principal
     amount for such period at the interest rate which such Lender would bid
     were it to bid, at the commencement of such period, for dollar deposits of
     a comparable amount and period from other banks in the eurodollar market.

A certificate of any Lender setting forth in reasonable detail the amount or
amounts (and the calculation thereof) that such Lender is entitled to receive
pursuant to this Section shall be delivered to the Borrower and shall be
conclusive absent manifest error. The Borrower shall pay

                                       36
<PAGE>

such Lender the amount shown as due on any such certificate within 10 days after
receipt thereof.

       SECTION 2.14.  Taxes
                      -----

       (a)    Any and all payments by or on account of any obligation of the
Borrower hereunder or under any other Loan Document shall be made free and clear
of and without deduction for any Indemnified Taxes or Other Taxes; provided that
if the Borrower shall be required to deduct any Indemnified Taxes or Other Taxes
from such payments, then:

           (i)   the sum payable shall be increased as necessary so that after
     making all required deductions (including deductions applicable to
     additional sums payable under this Section 2.14(a)) the Administrative
                                        ---------------
     Agent, Lender or Issuing Bank (as the case may be) receives an amount equal
     to the sum it would have received had no such deductions been made;

           (ii)  the Borrower shall make such deductions; and

           (iii) the Borrower shall pay the full amount deducted to the relevant
     Governmental Authority in accordance with applicable law.

       (b)  In addition, the Borrower shall pay any Other Taxes to the relevant
Governmental Authority in accordance with applicable law.

       (c)  The Borrower shall indemnify the Administrative Agent, each Lender
and the Issuing Bank, within 10 days after written demand therefor, for the full
amount of any Indemnified Taxes or Other Taxes paid by the Administrative Agent,
such Lender or the Issuing Bank, as the case may be, on or with respect to any
payment by or on account of any obligation of the Borrower hereunder or under
any other Loan Document (including Indemnified Taxes or Other Taxes imposed or
asserted on or attributable to amounts payable under this Section 2.14(c)) and
                                                          ---------------
any penalties, interest and reasonable expenses (other than penalties, interest
and expenses resulting from the gross negligence or willful misconduct of the
Administrative Agent, such Lender or the Issuing Bank, as the case may be)
arising therefrom or with respect thereto, whether or not such Indemnified Taxes
or Other Taxes were correctly or legally imposed or asserted by the relevant
Governmental Authority.  A certificate as to the amount of such payment or
liability delivered to the Borrower by a Lender or the Issuing Bank, or by the
Administrative Agent on its own behalf or on behalf of a Lender or the Issuing
Bank, shall be conclusive absent manifest error.

       (d)   As soon as practicable after any payment of Indemnified Taxes or
Other Taxes by the Borrower to a Governmental Authority, the Borrower shall
deliver to the Administrative Agent the original or a certified copy of a
receipt issued by such Governmental Authority evidencing such payment, a copy of
the return reporting such payment or other evidence of such payment reasonably
satisfactory to the Administrative Agent.

       (e)   Any Foreign Lender that is entitled to an exemption from or
reduction of withholding tax under the law of the jurisdiction in which the
Borrower is located, or any treaty to which such jurisdiction is a party, with
respect to payments under this Agreement shall deliver

                                       37
<PAGE>

to the Borrower (with a copy to the Administrative Agent), at the time or times
prescribed by applicable law, such properly completed and executed documentation
prescribed by applicable law or reasonably requested by the Borrower as will
permit such payments to be made without withholding or at a reduced rate.

          (f)   The Issuing Bank and each Lender that grants a participation
shall:

             (i)   withhold or deduct from each payment to the holder of such
     participation any Taxes required to be withheld or deducted from such
     payment by such Issuing Bank or Lender and not withheld or deducted
     therefrom by the Borrower or the Administrative Agent;

             (ii)  pay the full amount deducted to the relevant Governmental
     Authority in accordance with applicable law; and

             (iii) indemnify the Borrower and the Administrative Agent for any
     losses, costs and expenses that they may incur as a result of any failure
     to so withhold or deduct and pay such taxes.

          SECTION 2.15.  Payments Generally; Pro Rata Treatment; Sharing of
                         --------------------------------------------------
Set-offs.
--------

          (a)   The Borrower shall make each payment required to be made by it
hereunder or under any other Loan Document (whether of principal, interest, fees
or reimbursement of LC Disbursements, or of amounts payable under Section 2.12,
                                                                  ------------
2.13 or 2.14, or otherwise) prior to the time expressly required hereunder or
----    ----
under such other Loan Document for such payment (or, if no such time is
expressly required, prior to 12:00 noon, New York City time), on the date when
due, in immediately available funds, without set-off, recoupment or
counterclaim.  Any amounts received after such time on any date may, in the
discretion of the Administrative Agent, be deemed to have been received on the
next succeeding Business Day for purposes of calculating interest thereon.  All
such payments shall be made to the Administrative Agent at its offices at 270
Park Avenue, New York, New York, except payments to be made directly to the
Issuing Bank as expressly provided herein and except that payments pursuant to

Sections 2.12, 2.13, 2.14 and 9.03 shall be made directly to the Persons
-------------------------     ----
entitled thereto and payments pursuant to other Loan Documents shall be made to
the Persons specified therein.  The Administrative Agent shall distribute any
such payments received by it for the account of any other Person to the
appropriate recipient promptly following receipt thereof.  If any payment under
any Loan Document shall be due on a day that is not a Business Day, the date for
payment shall be extended to the next succeeding Business Day, and, in the case
of any payment accruing interest, interest on the principal portion of such
payment shall be payable for the period of such extension.  All payments under
each Loan Document shall be made in dollars.

          (b)   If at any time insufficient funds are received by and available
to the Administrative Agent to pay fully all amounts of principal, unreimbursed
LC Disbursements, interest and fees then due hereunder, such funds shall be
applied:

             (i)  first, towards payment of interest and fees then due
     hereunder, ratably among the parties entitled thereto in accordance with
     the amounts of interest and fees then due to such parties, and

                                       38
<PAGE>

             (ii)  second, towards payment of principal and unreimbursed LC
     Disbursements then due hereunder, ratably among the parties entitled
     thereto in accordance with the amounts of principal and unreimbursed LC
     Disbursements then due to such parties.

          (c)  If any Lender shall, by exercising any right of set-off,
recoupment or counterclaim or otherwise, obtain payment in respect of any
principal of or interest on any of its Loans or participations in LC
Disbursements resulting in such Lender receiving payment of a greater proportion
of the aggregate amount of its Loans, and participations in LC Disbursements and
accrued interest thereon than the proportion received by any other Lender, then
the Lender receiving such greater proportion shall purchase (for cash at face
value) participations in the Loans and participations in LC Disbursements of
other Lenders to the extent necessary so that the benefit of all such payments
shall be shared by the Lenders ratably in accordance with the aggregate amount
of principal of and accrued interest on their respective Loans, and
participations in LC Disbursements; provided that:

             (i)   if any such participations are purchased and all or any
     portion of the payment giving rise thereto is recovered, such
     participations shall be rescinded and the purchase price restored to the
     extent of such recovery, without interest, and

             (ii)  the provisions of this paragraph shall not be construed to
     apply to any payment made by the Borrower pursuant to and in accordance
     with the express terms of this Agreement or any payment obtained by a
     Lender as consideration for the assignment of or sale of a participation in
     any of its Loans or participations in LC Disbursements to any assignee or
     participant, other than to the Borrower or any Subsidiary or Affiliate
     thereof (as to which the provisions of this paragraph shall apply).

The Borrower consents to the foregoing and agrees, to the extent it may
effectively do so under applicable law, that any Lender acquiring a
participation pursuant to the foregoing arrangements may exercise against the
Borrower rights of set-off, recoupment and counterclaim with respect to such
participation as fully as if such Lender were a direct creditor of the Borrower
in the amount of such participation.

          (d)  Unless the Administrative Agent shall have received notice from
the Borrower prior to the date on which any payment is due to the Administrative
Agent for the account of the Lenders or the Issuing Bank hereunder that the
Borrower will not make such payment, the Administrative Agent may assume that
the Borrower has made such payment on such date in accordance herewith and may,
in reliance upon such assumption, distribute to the Lenders or the Issuing Bank,
as the case may be, the amount due. In such event, if the Borrower has not in
fact made such payment, then each of the Lenders or the Issuing Bank, as the
case may be, severally agrees to repay to the Administrative Agent forthwith on
demand the amount so distributed to such Lender or Issuing Bank with interest
thereon, for each day from and including the date such amount is distributed to
it to but excluding the date of payment to the Administrative Agent, at the
greater of the Federal Funds Effective Rate and a rate determined by the
Administrative Agent in accordance with banking industry rules on interbank
compensation.

                                       39
<PAGE>

          (e)    If any Lender shall fail to make any payment required to be
made by it pursuant to Section 2.02(d) or (e), 2.05(b), 2.15(d) or 9.03(c), then
                       ---------------    ---  -------  -------    -------
the Administrative Agent may, in its discretion (notwithstanding any contrary
provision hereof), apply any amounts thereafter received by the Administrative
Agent for the account of such Lender to satisfy such Lender's obligations under
such Sections until all such unsatisfied obligations are fully paid.

          SECTION 2.16.  Mitigation Obligations; Replacement of Lenders
                         ----------------------------------------------

          (a)    If any Lender requests compensation under Section 2.12, or if
                                                           ------------
the Borrower is required to pay any additional amount to any Lender or any
Governmental Authority for the account of any Lender pursuant to Section 2.14,
                                                                 ------------
then such Lender shall use reasonable efforts to designate a different lending
office for funding or booking its Loans hereunder or to assign its rights and
obligations hereunder to another of its offices, branches or Affiliates, if, in
the reasonable judgment of such Lender, such designation or assignment (i) would
eliminate or reduce amounts payable pursuant to Section 2.12 or 2.14, as the
                                                ------------    ----
case may be, in the future and (ii) would not subject such Lender to any
material unreimbursed cost or expense and would not otherwise be disadvantageous
to such Lender.  The Borrower hereby agrees to pay all reasonable costs and
expenses incurred by any Lender in connection with any such designation or
assignment.

          (b)    If any Lender requests compensation under Section 2.12, or if
                                                           ------------
the Borrower is required to pay any additional amount to any Lender or any
Governmental Authority for the account of any Lender pursuant to Section 2.14,
                                                                 ------------
or if any Lender defaults in its obligation to fund Loans hereunder, then the
Borrower may, at its sole expense and effort, upon notice to such Lender and the
Administrative Agent, require such Lender to assign and delegate, without
recourse (in accordance with and subject to the restrictions contained in

Section 9.04), all its interests, rights and obligations under this Agreement to
------------
an assignee that shall assume such obligations (which assignee may be another
Lender, if a Lender accepts such assignment); provided that:

            (i)   the Borrower shall have received the prior written consent of
     the Administrative Agent and the Issuing Bank, which consent shall not
     unreasonably be withheld;

            (ii)  such Lender shall have received payment of an amount equal to
     the outstanding principal of its Loans and participations in LC
     Disbursements, accrued interest thereon, accrued fees and all other amounts
     payable to it hereunder, from the assignee (to the extent of such
     outstanding principal and accrued interest and fees) or the Borrower (in
     the case of all other amounts); and

            (iii) in the case of any such assignment resulting from a claim for
     compensation under Section 2.12 or payments required to be made pursuant to
                        ------------
     Section 2.14, such assignment will result in a material reduction in such
     ------------
     compensation or payments.

                                       40
<PAGE>

A Lender shall not be required to make any such assignment and delegation if,
prior thereto, as a result of a waiver by such Lender or otherwise, the
circumstances entitling the Borrower to require such assignment and delegation
cease to apply.

                                  ARTICLE III
                                  -----------

                         Representations and Warranties
                         ------------------------------

          The Borrower represents and warrants to the Lenders that, as of each
Credit Event Date:

          SECTION 3.01.  Organization; Powers. Each of the Borrower and each of
                         --------------------
its Subsidiaries is duly organized, validly existing and in good standing under
the laws of the jurisdiction of its organization, has all requisite power and
authority to carry on its business as now conducted and, except where the
failure to do so, individually or in the aggregate, could not reasonably be
expected to result in a Material Adverse Effect, is qualified to do business in,
and is in good standing in, every jurisdiction where such qualification is
required.

          SECTION 3. 02. Authorization; Enforceability. The Transactions to be
                         -----------------------------
consummated by each Loan Party on or prior to such Credit Event Date are within
such Loan Party's corporate or other powers and have been duly authorized by
such Loan Party by all necessary corporate or other action. This Agreement has
been duly executed and delivered by the Borrower and constitutes, and each other
Loan Document to which any Loan Party is to be a party, when executed and
delivered by such Loan Party, will constitute, a legal, valid and binding
obligation of the Borrower or such Loan Party (as the case may be), enforceable
in accordance with its terms, subject to applicable bankruptcy, insolvency,
reorganization, moratorium or other laws affecting creditors' rights generally
and subject to general principles of equity, regardless of whether considered in
a proceeding in equity or at law.

          SECTION 3.03.  Governmental Approvals; No Conflicts. The Transactions
                         ------------------------------------
occurring on or prior to such Credit Event Date:

          (a)   do not require any consent or approval of, registration or
filing with, or any other action by, any Governmental Authority, except (x) such
as have been obtained or made and are in full force and effect, and (y) consents
required to be obtained by the Lenders to make Loans hereunder or by the Issuing
Bank to issue Letters of Credit hereunder;

          (b)   will not violate (x) any applicable law or regulation or any
order or license of any Governmental Authority applicable to the Borrower or any
of its Subsidiaries or (y) the charter, by-laws or other organizational
documents of the Borrower or any of its Subsidiaries;

          (c)   will not violate or result in a default under any indenture,
agreement or other instrument governing or relating to any Indebtedness binding
upon the Borrower or any of its Subsidiaries or any of such Person's assets, or
give rise to a right thereunder to require any payment to be made by the
Borrower or any of its Subsidiaries, or any material breach of any other
material agreement binding on any of the Borrower or any of its Subsidiaries;
and

                                       41
<PAGE>

          (d)   will not result in the creation or imposition of any Lien on any
asset of the Borrower or any of its Subsidiaries (other than Permitted Liens).

          SECTION 3.04.  Financial Condition; No Material Adverse Change.
                         -----------------------------------------------

          (a)  The Borrower has heretofore furnished to the Administrative Agent
its  consolidated balance sheet as of December 31, 2000.  Such consolidated
balance sheet (i) has been prepared in good faith based on assumptions believed
by the Borrower to be reasonable, (ii) is based on the best information
available to the Borrower after due inquiry, (iii) accurately reflects all
adjustments necessary to give effect to the Transactions and (iv) presents
fairly, in all material respects, the financial position of the Borrower and its
consolidated Subsidiaries as of December 31, 2000.

          (b)  Except as disclosed in the consolidated balance sheet referred to
above and except for the Disclosed Matters, after giving effect to the
Transactions occurring on or prior to such Credit Event Date, neither the
Borrower nor any of its Subsidiaries has, as of such Credit Event Date, any
material contingent liabilities, unusual long-term commitments or unrealized
losses.

          (c)  Since December 31, 2000, there has been no material adverse
change in the business, assets, operations, prospects or condition, financial or
otherwise, of the Borrower and its Subsidiaries, taken as a whole. To the best
knowledge of the Borrower, after due inquiry, since December 31, 2000, there has
been no material adverse change in the business, assets, financial condition or
operations of PPL Corporation and its subsidiaries, taken as a whole, which
materially and adversely affects the ability of the Borrower to perform any of
its obligations hereunder.

          SECTION 3.05.  Properties.
                         ----------

          (a)    The Borrower and its Subsidiaries have obtained good title to,
valid leasehold interests in or other rights to all real and personal property,
including all easements, licenses, crossing rights and other appurtenant rights
necessary to own (or lease) and operate the Montana Assets and perform their
respective obligations under the Loan Documents and the Material Agreements,
subject to minor defects in title that do not materially interfere with their
ability to conduct their respective businesses as currently conducted or to
utilize such properties for their intended purposes, except if the failure to
have such title, leasehold interests or other rights could not reasonably be
expected to result in a Material Adverse Effect.

          (b)    Each of the Borrower and each of its Subsidiaries owns, or is
licensed to use, all trademarks, tradenames, copyrights, patents and other
intellectual property used by it and material to its business, and, to the best
knowledge of such Person after due inquiry, the use thereof by such Person does
not infringe upon the rights of any other Person, except for any such
infringements that, individually or in the aggregate, could not reasonably be
expected to result in a Material Adverse Effect.

          (c)    Schedule 3.05 sets forth the address of each item of real
property that is owned or leased by the Borrower or any of its Subsidiaries.

                                       42
<PAGE>

         SECTION 3.06.  Litigation and Environmental Matters.
                        ------------------------------------

          (a)    Except for Disclosed Matters, there are no actions, suits or
proceedings by or before any arbitrator or Governmental Authority pending
against or, to the knowledge of the Borrower, threatened against or affecting
the Borrower or any of its Subsidiaries (i) as to which there is a reasonable
possibility of an adverse determination and that, if adversely determined, could
reasonably be expected, individually or in the aggregate, to result in a
Material Adverse Effect or (ii) that involve any of the Loan Documents or the
Transactions occurring on or prior to such Credit Event Date.

          (b)    Except for the Disclosed Matters and except with respect to any
other matters that, individually or in the aggregate, could not reasonably be
expected to result in a Material Adverse Effect, neither the Borrower nor any of
its Subsidiaries (i) has failed to comply with any Environmental Law or to
obtain, maintain or comply with any permit, license or other approval required
under any Environmental Law, (ii) has become subject to any Environmental
Liability, (iii) has received notice of any claim with respect to any
Environmental Liability or (iv) knows of any reasonably valid basis for any
Environmental Liability.

          (c)    Since the date of this Agreement, there has been no change in
the status of the Disclosed Matters that, individually or in the aggregate, has
resulted in, or materially increased the likelihood of, a Material Adverse
Effect.

          SECTION 3.07.  Compliance with Laws and Agreements. Each of the
                         ---------------------------------------
Borrower and each of its Subsidiaries is in compliance with all laws,
regulations and orders of any Governmental Authority applicable to it or its
property and all indentures, agreements and other instruments binding upon it or
its property, except where the failure to do so, individually or in the
aggregate, could not reasonably be expected to result in a Material Adverse
Effect. No Default has occurred and is continuing.

          SECTION 3.08.  Investment and Holding Company Status. Neither the
                         -------------------------------------
Borrower nor any of its Subsidiaries is (a) an "investment company" as defined
in, or subject to regulation under, the Investment Company Act of 1940 or (b) a
"holding company" as defined in, or subject to regulation under, the Public
Utility Holding Company Act of 1935.

           SECTION 3.09.  Taxes.  Each of the Borrower and each of its
                          -----
Subsidiaries has timely filed or caused to be filed all Tax returns and reports
required to have been filed and has paid or caused to be paid all Taxes required
to have been paid by it, except (a) any Taxes that are being contested in good
faith by appropriate proceedings and for which such Person has set aside on its
books adequate reserves or (b) to the extent that the failure to do so could not
reasonably be expected to result in a Material Adverse Effect.

     SECTION 3.10.  ERISA.  No ERISA Event has occurred or is reasonably
                    -----
expected to occur that, when taken together with all other such ERISA Events for
which liability is reasonably expected to occur, could reasonably be expected to
result in a Material Adverse Effect. The present value of all accumulated
benefit obligations under each Plan (based on the assumptions used for purposes
of Statement of Financial Accounting Standards No. 87) did not, as of the date
of the most recent financial statements, if any, reflecting such amounts, exceed
by

                                       43
<PAGE>

more than $10,000,000 the fair market value of the assets of such Plan, and the
present value of all accumulated benefit obligations of all underfunded Plans
(based on the assumptions used for purposes of Statement of Financial Accounting
Standards No. 87) did not, as of the date of the most recent financial
statements reflecting such amounts, exceed by more than $10,000,000 the fair
market value of the assets of all such underfunded Plans.

                SECTION 3.11.  Disclosure.  The Borrower has disclosed to the
                               -----------
Lenders all agreements, instruments and corporate or other restrictions to which
the Borrower or any of its Subsidiaries is subject, and all other factual
matters pertaining to the assets, affairs or property of the Borrower and its
Subsidiaries known to any of them, that, individually or in the aggregate, could
reasonably be expected to result in a Material Adverse Effect. No reports,
financial statements, certificates or other information furnished by or on
behalf of the Borrower or any of its Subsidiaries to the Administrative Agent or
any Lender in connection with the negotiation of this Agreement or any other
Loan Document or delivered hereunder or thereunder (as modified or supplemented
by other information so furnished), taken as a whole, contains any material
misstatement of fact or omits to state any material fact necessary to make the
statements therein, in the light of the circumstances under which they were
made, not misleading; provided that, with respect to projected financial
information, the Borrower represents only that such information was prepared in
good faith based upon assumptions believed to be reasonable at the time.

               SECTION 3.12.  Subsidiaries.  Schedule 3.12 sets forth the name
                              ------------   -------------
of, and the ownership interest of the Borrower in, each subsidiary of the
Borrower and indicates whether such Subsidiary is a Core Subsidiary or an
Additional Subsidiary.

               SECTION 3.13.  Insurance.  Schedule 3.13 sets forth a description
                              ---------   -------------
of all insurance to be maintained by or on behalf of the Borrower and its
Subsidiaries with respect to the Montana Assets. The Borrower shall maintain, at
a minimum, the level of insurance set forth on Schedule 3.13 unless such
coverage is not commercially available, in which case the Borrower shall
maintain a level of insurance that is (a) the maximum prudent amount of coverage
that is commercially available as evidenced by a letter (in form and substance
satisfactory to the Administrative Agent) to that effect from the Insurance
Consultant or another third party recognized as an insurance expert and
acceptable to the Administrative Agent and (b) substantially conforming with the
insurance requirements set forth on Schedule 3.13. In respect of any such
insurance maintained, all premiums therefor then due and payable have been paid.
The Borrower believes that the insurance described on Schedule 3.13 is
                                                      -------------
appropriate.

          SECTION 3.14.  Labor Matters.  Except for any such event or
                         -------------
circumstance that could not reasonably be expected to result in a Material
Adverse Effect (a) there are no strikes, lockouts or slowdowns against the
Borrower or any of its Subsidiaries pending or, to the knowledge of the
Borrower, threatened; (b) the hours worked by and payments made to employees of
the Borrower and its Subsidiaries have not in any material respect been in
violation of the Fair Labor Standards Act or any other applicable federal,
state, local or foreign law dealing with such matters; (c) all payments due from
the Borrower or any of its Subsidiaries, or for which any claim may be made to
the Borrower or any of its Subsidiaries, on account of wages and employee health
and welfare insurance and other benefits, have been paid or accrued as a
liability on the books of such Person; and (d) the consummation of the
Transactions will not

                                       44
<PAGE>

give rise to any right of termination or right of renegotiation on the part of
any union under any collective bargaining agreement to which the Borrower or any
of its Subsidiaries is bound.

          SECTION 3.15.  Solvency.  Immediately after the consummation of the
                         --------
Transactions to occur on such Credit Event Date and immediately following the
making of each Loan made on such Credit Event Date, if any, and after giving
effect to the application of the proceeds of such Loans and the issuance of any
Letter of Credit:

          (a)    the fair value of the assets of each of the Borrower and each
of its Subsidiaries, at a fair valuation, will exceed such Person's debts and
liabilities, subordinated, contingent or otherwise;

          (b)    the present fair saleable value of the property of each of the
Borrower and each of its Subsidiaries will be greater than the amount that will
be required to pay the probable liability of such Person's debts and other
liabilities, subordinated, contingent or otherwise, as such debts and other
liabilities become absolute and matured;

          (c)    each of the Borrower and each of its Subsidiaries will be able
to pay its debts and liabilities, subordinated, contingent or otherwise, as such
debts and liabilities become absolute and matured; and

          (d)    each of the Borrower and each of its Subsidiaries will not have
unreasonably small capital with which to conduct the business in which it is
engaged as such business is now conducted and is proposed to be conducted
following such Credit Event Date.

          SECTION 3.16.  Federal Reserve Regulations.
                         ---------------------------

          (a)    Neither the Borrower nor any of its Core Subsidiares is engaged
principally, or as one of its important activities, in the business of extending
credit for the purpose of purchasing or carrying margin stock (within the
meaning of Regulation T, U or X of the Board).

          (b)    No part of the proceeds of the Loans will be used, whether
directly or indirectly, and whether immediately, incidentally or ultimately, for
any purpose which entails a violation of the provisions of the regulations of
the Board, including Regulation T, U or X thereof.

          SECTION 3.17.  No Burdensome Restrictions. No applicable governmental
                         --------------------------
approval, order or license or applicable law or regulation has, or could
reasonably be expected to have, in light of all facts and circumstances of which
Borrower has actual knowledge, a material adverse effect on (a) the ability of
the Borrower or any of its Subsidiaries to perform its obligations under the
Loan Documents to which it is a party or (b) the validity or enforceability of
any of the Loan Documents or the rights and remedies of the Administrative Agent
and the Lenders thereunder.

          SECTION 3.18.  Energy Regulation.  Each of the Borrower and its Core
                         -----------------
Subsidiaries is exempt from regulation under PUHCA as an Exempt Wholesale
Generator and is exempt from state laws and regulations respecting the rates or
the financial or organizational

                                       45
<PAGE>

regulation of electric utilities. Each of the Borrower and its Core Subsidiaries
have taken all actions and received all approvals and orders necessary under the
Federal Power Act in order to consummate the Transactions occurring on or prior
to such Credit Event Date. None of the Administrative Agent, the Lenders or any
of their Affiliates will, solely as a result of the Transactions occurring on or
prior to such Credit Event Date, be subject to, or not exempt from, regulation
under the Federal Power Act or PUHCA or under state laws and regulations
respecting the rates or the financial or organizational regulation of electric
utilities.

               SECTION 3.19.  Letters of Credit. Each of the Borrower and its
                              -----------------
Core Subsidiaries acknowledges that it is not obligated under any agreement,
document or instrument to provide any letter of credit, the stated amount of
which could materially increase other than (i) fixed price forward contracts
that require physical delivery of a commodity or (ii) derivative financial
instruments entered into to manage risks associated with energy price
fluctuations that require a letter of credit (or financial assurances that can
be provided in the form of a letter of credit).

                                  ARTICLE IV

                                  Conditions
                                  ----------

               SECTION 4.01.  Closing Date. The obligations of the Lenders to
                              ------------
make initial Loans and of the Issuing Bank to issue initial Letters of Credit
hereunder shall not become effective until the date on which each of the
following conditions is satisfied (or waived in accordance with Section 9.02):
                                                                ------------

     (a)    Credit and Reimbursement Agreement.  The Administrative Agent shall
            ----------------------------------
have received from each party hereto either (i) a counterpart of this Agreement
signed on behalf of such party or (ii) written evidence satisfactory to the
Administrative Agent (which may include telecopy transmission of a signed
signature page of this Agreement) that such party has signed a counterpart of
this Agreement.

     (b)    PPL Corporation Commitment.  The Administrative Agent shall have
            --------------------------
received the Parent Letter Agreement duly executed by all of the parties
thereto.

     (c)    Legal Opinions.  The Administrative Agent shall have received a
            --------------
favorable written opinion (addressed to the Administrative Agent and the Lenders
and dated the Closing Date) of (i) David Kinnard, General Counsel of the
Borrower, (ii) Orrick, Herrington & Sutcliffe LLP, counsel for the Borrower, and
(iii) Michael A. McGrall, General Counsel to PPL Corporation, in the case of
each such opinion required by this clause (d), covering such other matters
relating to the Loan Parties, the Loan Documents or the Transactions as the
Required Lenders shall reasonably request.  The Borrower hereby requests the
applicable counsel to deliver such opinions and reliance letters.

     (d)    Corporate Matters.  The Administrative Agent shall have received
            -----------------
such documents and certificates as the Administrative Agent or its counsel may
reasonably request relating to the organization, existence and good standing of
the Borrower and each of its Subsidiaries, the authorization of the Transactions
and any other legal matters relating to the

                                       46
<PAGE>

Borrower and its Subsidiaries, the Loan Documents or such Transactions, all in
form and substance reasonably satisfactory to the Administrative Agent and its
counsel.

     (e)    Compliance Certificate.  The Administrative Agent shall have
            ----------------------
received a certificate, dated the Closing Date and signed by the President, a
Vice President or a Financial Officer of the Borrower, confirming compliance
with the conditions set forth in paragraphs (a) and (b) of Section 4.02.
                                                           ------------

     (f)    No Defaults Under Material Agreements.  The Administrative Agent
            -------------------------------------
shall have received a certificate, dated the Closing Date and signed by the
President, a Vice President or a Financial Officer of the Borrower, stating that
no event of default, or event or condition that, upon notice, lapse or time or
both would, unless cured or waived, become an event of default, has occurred and
is continuing under any of the Material Agreements.

     (g)    Fees and Expenses.  The Administrative Agent shall have received all
            -----------------
fees and other amounts due and payable any of the Lenders or the Administrative
Agent on or prior to the Closing Date, including, to the extent invoiced,
reimbursement or payment of all out-of-pocket expenses (including fees, charges
and disbursements of counsel) required to be reimbursed or paid by the Borrower
or its Core Subsidiaries hereunder or under any other Loan Document.

     (h)    Lien Searches.  The Administrative Agent shall have received the
            -------------
results of a search of the Uniform Commercial Code (or equivalent) filings made
with respect to the Borrower and its Subsidiaries in the jurisdictions listed on
Schedule 4.01(h) and copies of the financing statements (or similar documents)
----------------
disclosed by such search and evidence reasonably satisfactory to the Lenders
that the Liens indicated by such financing statements (or similar documents) are
permitted by Section 6.02 or have been released pursuant to documentation
             ------------
satisfactory to the Lenders.

     (i)    Insurance.  The Administrative Agent shall have received insurance
            ---------
certificates (or binders, if certificates are not then available) reasonably
satisfactory to the Lenders evidencing that the insurance required by Section
                                                                      -------
5.07 is in effect.
----

     (j)    Power Marketing Plan.  The Administrative Agent shall have received,
            --------------------
and the Lenders shall be reasonably satisfied with the contents of, a written
plan for the sales of power by the Borrower and its Subsidiaries through the
Borrower's fiscal year ending December 2004.

     (k)    Governmental Approvals.  All consents and approvals required to be
            ----------------------
obtained from any Governmental Authority or other Person in connection with the
Transactions occurring contemplated hereby and the continuing operations of the
Borrower and its Subsidiaries shall have been obtained and be in full force and
effect, and all applicable waiting periods and appeal periods shall have
expired, except as set forth on Schedule 4.01(k), in each case, without any
                                ----------------
action being taken or threatened by any competent authority which would
restrain, prevent or otherwise impose adverse conditions on the Transactions or
the continuing operations of the Borrower and its Subsidiaries, except, in the
case of consents and approvals required to be obtained in connection with the
continuing operations of the Borrower and its

                                       47
<PAGE>

Subsidiaries, where the failure to obtain such consents and approvals could not
reasonably be expected to result in a Material Adverse Effect.

     (l)    Capital Structure; Financial Statements.  The Lenders shall be
            ---------------------------------------
reasonably satisfied with the capital structure of the Borrower and its
Subsidiaries.  The Administrative Agent shall have received:

           (i) a consolidated balance sheet of the Borrower and its Subsidiaries
     as of December 31, 2000, in form and substance reasonably satisfactory to
     the Administrative Agent and shall be consistent in all material respects
     with the forecasts and other information previously provided to the
     Lenders;

           (ii) consolidated projected cash flow and income statements for the
     Borrower and its Subsidiaries for the three-year period following the
     Closing Date, in form and substance reasonably satisfactory to the
     Administrative Agent and shall be consistent in all material respects with
     the forecasts and other information previously provided to the Lenders; and

           (iii)  the most recent Form 10-K and most recent Form 10-Q of PPL
     Corporation and the Borrower filed with the Securities and Exchange
     Commission and any Form 8-K of PPL Corporation or the Borrower filed with
     the Securities and Exchange Commission simultaneously with or after the
     most recent Form 10-Q (or Form 10-K if more recent) of PPL Corporation or
     the Borrower, as applicable, filed with the Securities and Exchange
     Commission.

     (m)    Working Capital.  The Lead Arranger shall be reasonably satisfied
            ---------------
with the sufficiency of the projected internal cash generation of the Borrower
and its Subsidiaries and the amounts available under the Commitments and the
commitments under the Existing Credit Agreement to meet the ongoing working
capital needs of the Borrower and its Subsidiaries during the remainder of the
Availability Period.

     (n)    Service of Process.  The Administrative Agent shall have received
            ------------------
evidence in form and substance satisfactory to it that the Borrower has
irrevocably designated, appointed and empowered CT Corporation System, with
offices on the date hereof at 111 Eighth Avenue, New York, New York 10011, as
its designee, appointee and agent to receive and accept for and on its behalf
service of any and all legal process, summons, notices and documents which may
be served in any legal action or proceeding against the Borrower with respect to
this Agreement or any of the other Loan Documents brought in the Supreme Court
of the State of New York sitting in New York County or of the United States
District Court of the Southern District of New York, or any appellate court from
any thereof.

     (o)    Amendment.  The Existing Credit Agreement shall be amended to the
            ---------
satisfaction of the Lead Arranger to permit the incurrence of indebtedness
hereunder.

The Administrative Agent shall notify the Borrower and the Lenders of the
Closing Date, and such notice shall be conclusive and binding. Notwithstanding
the foregoing, the obligations of the Lenders to make Loans and of the Issuing
Bank to issue Letters of Credit hereunder shall not become effective unless each
of the foregoing conditions is satisfied (or waived pursuant to
                                       48
<PAGE>

Section 9.02) at or prior to 5:00 p.m., New York City time, on the last day of
------------
the Availability Period (and, in the event such conditions are not so satisfied
or waived, the Commitments shall terminate at such time).

          SECTION 4.02.  Each Credit Event. The obligation of each Lender to
                         -----------------
make a Loan on the occasion of any Borrowing, and of the Issuing Bank to issue,
amend, renew or extend any Letter of Credit, is subject to receipt of the
request therefor in accordance herewith and to the satisfaction of the following
conditions:

          (a)    Representations and Warranties. The representations and
                 ------------------------------
warranties of each Loan Party set forth in the Loan Documents shall be true and
correct in all material respects on and as of the date of such Borrowing or the
date of issuance, amendment, renewal or extension of such Letter of Credit, as
applicable, except to the extent such representations and warranties are stated
to have been made solely as of an earlier date, in which case such
representations and warranties shall have been true and correct in all material
respects on and as of such earlier date.

          (b)    No Defaults. At the time of and immediately after giving effect
                 -----------
to such Borrowing or the issuance, amendment, renewal or extension of such
Letter of Credit, as applicable, no Default shall have occurred and be
continuing.

Each Borrowing and each issuance, amendment, renewal or extension of a Letter of
Credit shall be deemed to constitute a representation and warranty by the
Borrower on the date thereof as to the matters specified in paragraphs (a) and
(b) of this Section.

                                   ARTICLE V

                             Affirmative Covenants
                             ---------------------

          Until the Commitments have expired or been terminated and the
principal of and interest on each Loan and all fees payable hereunder shall have
been paid in full and all Letters of Credit shall have expired or terminated and
all LC Disbursements shall have been reimbursed, the Borrower covenants and
agrees with the Lenders that:

          SECTION 5.01. Financial Statements and Other Information. The Borrower
                        ------------------------------------------
will furnish to the Administrative Agent (and, in the case of clauses (a), (b)
and (c) of this Section 5.01, the Administrative Agent will furnish copies
                ------------
thereof to the Lenders):

               (a) within 90 days after the end of each fiscal year of the
     Borrower, its audited consolidated balance sheet and related statements of
     operations, members' equity and cash flows as of the end of and for such
     year, setting forth in each case in comparative form the figures for the
     previous fiscal year, all reported on by PricewaterhouseCoopers or other
     independent public accountants of recognized national standing (without a
     "going concern" or like qualification or exception and without any
     qualification or exception as to the scope of such audit) to the effect
     that such consolidated financial statements present fairly in all material
     respects the financial

                                       49
<PAGE>

     condition and results of operations of the Borrower and its consolidated
     Subsidiaries on a consolidated basis in accordance with GAAP consistently
     applied;

               (b)    within 60 days after the end of each of the first three
     fiscal quarters of each fiscal year of the Borrower, its consolidated
     balance sheet and related statements of operations, members' equity and
     cash flows as of the end of and for such fiscal quarter and the then
     elapsed portion of the fiscal year, setting forth in each case in
     comparative form the figures for the corresponding period or periods of
     (or, in the case of the balance sheet, as of the end of) the previous
     fiscal year, all certified by one of its Financial Officers as presenting
     fairly in all material respects the financial condition and results of
     operations of the Borrower and its consolidated Subsidiaries on a
     consolidated basis in accordance with GAAP consistently applied, subject to
     normal year-end audit adjustments and the absence of footnotes;

               (c)    concurrently with any delivery of financial statements
     under clause (a) or (b) above, a certificate of a Financial Officer of the
     Borrower:

               (i)    certifying as to whether a Default has occurred and, if a
          Default has occurred, specifying the details thereof and any action
          taken or proposed to be taken with respect thereto,

               (ii)   setting forth reasonably detailed calculations
          demonstrating compliance with Section 6.11 and
                                        ------------

               (iii)  except in the case of the first set of financial
          statements delivered under this Section 5.01, stating whether any
                                          ------------
          change in GAAP or in the application thereof has occurred since the
          date of the first set of financial statements delivered under this
          Section 5.01 and, if any such change has occurred, specifying the
          ------------
          effect of such change on the financial statements accompanying such
          certificate;

               (d)    concurrently with any delivery of financial statements
     under clause (a) above, a certificate of the accounting firm that reported
     on such financial statements stating whether they obtained knowledge during
     the course of their examination of such financial statements of any Default
     (which certificate may be limited to the extent required by accounting
     rules or guidelines);

               (e)    at least 30 days prior to the commencement of each fiscal
     year of the Borrower, a detailed consolidated budget for such fiscal year
     (including a projected consolidated balance sheet and related statements of
     projected operations and cash flow as of the end of and for such fiscal
     year and setting forth the assumptions used for purposes of preparing such
     budget) and, promptly when available, any significant revisions of such
     budget;

               (f)    promptly after the Borrower's receipt thereof, a copy of
     any management letter or other similar communication received by the
     Borrower from its independent public accountants in relation to the
     Borrower's financial, accounting and other systems, management or accounts;

                                       50
<PAGE>

               (g) promptly following the Borrower's receipt of any request
     therefor, such other information regarding the operations, business affairs
     and financial condition of the Borrower or any Subsidiary, or compliance
     with the terms of any Loan Document, as the Administrative Agent (for
     itself or on behalf of any Lender) may reasonably request.

               SECTION 5.02.  Notices of Material Events. The Borrower will
                              --------------------------
furnish to the Administrative Agent prompt written notice of the following:

               (a)  the occurrence of any Default;

               (b)  the filing or commencement of any action, suit or proceeding
     by or before any arbitrator or Governmental Authority against or affecting
     the Borrower or any Affiliate thereof that, if adversely determined, could
     reasonably be expected to result in a Material Adverse Effect;

               (c)  the occurrence of any ERISA Event that, alone or together
     with any other ERISA Events that have occurred, could reasonably be
     expected to result in a Material Adverse Effect; and

               (d)  any other development known to the Borrower that results in,
     or could reasonably be expected to result in, a Material Adverse Effect.

Each notice delivered under this Section shall be accompanied by a statement of
a Financial Officer or other executive officer of the Borrower setting forth the
details of the event or development requiring such notice and any action taken
or proposed to be taken with respect thereto.

               SECTION 5.03.  Public Filings. The Borrower will use its
                              --------------
reasonable best efforts to furnish to the Administrative Agent, within 15 days
of the filing thereof with the Securities and Exchange Commission, each Form 10-
K, Form 10-Q and Form 8-K of PPL Corporation and the Borrower filed with the
Securities and Exchange Commission.

               SECTION 5.04.  Existence; Conduct of Business. The Borrower will,
                              ------------------------------
and will cause each of its Core Subsidiaries to, do or cause to be done all
things necessary to preserve, renew and keep in full force and effect its legal
existence and the rights, licenses, permits, privileges, franchises, patents,
copyrights, trademarks and trade names material to the conduct of its business;
provided that the foregoing shall not prohibit any merger, consolidation,
liquidation or dissolution permitted under Section 6.03.
                                           ------------

               SECTION 5.05.  Payment of Obligations. The Borrower will, and
                              ----------------------
will cause each of its Core Subsidiaries to, pay its Indebtedness and other
obligations (including Tax liabilities) in excess of $10,000,000 before the same
shall become delinquent or in default, except where (a) the validity or amount
thereof is being contested in good faith by appropriate proceedings, (b) the
Borrower or such Core Subsidiary has set aside on its books adequate reserves
with respect thereto in accordance with GAAP, and (c) the failure to make
payment could not reasonably be expected to result in a Material Adverse Effect.

                                       51
<PAGE>

               SECTION 5.06.  Maintenance of Properties. The Borrower will, and
                              -------------------------
will cause each of its Core Subsidiaries to, keep and maintain all property
material to the conduct of its business in good working order and condition,
ordinary wear and tear excepted.

               SECTION 5.07.  Insurance. The Borrower will, and will cause each
                              ---------
of its Core Subsidiaries to, maintain, with financially sound and reputable
insurance companies insurance in such amounts (with no greater risk retention)
and against such risks as are customarily maintained by companies of established
repute engaged in the same or similar businesses operating in the same or
similar locations. The Borrower will furnish to the Administrative Agent, upon
request (for itself or on behalf of any Lender), information in reasonable
detail as to the insurance so maintained.

               SECTION 5.08.  Books and Records; Inspection and Audit Rights;
                              -----------------------------------------------
Auditor. The Borrower will, and will cause each of its Core Subsidiaries to,
-------
keep proper books of record and account in which full, true and correct entries
in all material respects are made of all dealings and transactions in relation
to its business and activities. The Borrower will, and will cause each of its
Subsidiaries to, permit any representatives designated by the Administrative
Agent or any Lender, upon reasonable prior notice, to visit and inspect its
properties, to examine and make extracts from its books and records, and to
discuss its affairs, finances and condition with its officers and independent
accountants, all at such reasonable times and as often as reasonably requested.
The Borrower shall at all times retain a nationally recognized independent
accounting firm.

               SECTION 5.09.  Compliance with Laws. The Borrower will, and will
                              --------------------
cause each of its Core Subsidiaries to, comply with (a) all laws (including
Environmental Laws), rules, regulations and orders of any Governmental Authority
applicable to it or its property, and (b) its material contractual obligations,
except in each case where the failure to do so, individually or in the
aggregate, could not reasonably be expected to result in a Material Adverse
Effect.

               SECTION 5.10.  Use of Proceeds and Letters of Credit. The Letters
                              -------------------------------------
of Credit shall be issued solely to satisfy the Borrower's or a Core
Subsidiary's obligation to provide letters of credit required in the ordinary
course of business, provided that letters of credit required to support the
Borrower's or any of its Core Subsidiary's obligations in respect of
Indebtedness shall not be deemed to be in ordinary course of business. The
proceeds of the Loans shall be used solely to finance the Borrower's
reimbursement obligations in respect of such Letters of Credit. No part of the
proceeds of any Loan will be used, whether directly or indirectly, for any
purpose that entails a violation of any of the Regulations of the Board,
including Regulations T, U and X.

               SECTION 5.11.  Additional Subsidiaries. If any additional
                              -----------------------
Subsidiary is formed or acquired after the Closing Date, the Borrower will,
within three Business Days after such Subsidiary is formed or acquired;

               (a)  notify the Administrative Agent thereof;

               (b)  if such Subsidiary is a Core Subsidiary, cause such Core
     Subsidiary to execute and become party to a Subsidiary Guarantee Agreement;
     and

                                       52
<PAGE>

               (c)  deliver to the Administrative Agent the certificate of
     incorporation, by-laws or other organizational documents of such Subsidiary
     and any other documents regarding such Subsidiary as the Administrative
     Agent shall reasonably request.

               SECTION 5.12.  Energy Regulation. Each of the Borrower and its
                              -----------------
Core Subsidiaries shall (a) maintain its status as an Exempt Wholesale
Generator, (b) have the benefit of an exemption from regulation under PUHCA that
is not materially different from the exemption provided by Section 32 of PUHCA
or (c) not be subject to regulation under PUHCA because PUHCA shall have been
repealed.

               SECTION 5.13.  Further Assurances. The Borrower will, and will
                              ------------------
cause each of its Core Subsidiaries to, execute any and all further documents,
agreements and instruments, and take all such further actions as are necessary
to give effect to the transactions contemplated by the Loan Documents and to
protect the rights of the Administrative Agent and the Lenders thereunder, or as
are reasonably requested by the Administrative Agent or the Required Lenders.

               SECTION 5.14.  Power Marketing Plan. The Borrower shall update
                              --------------------
the power marketing plan delivered pursuant to Section 4.01(j) every three years
                                               --------------
and shall deliver such updated power marketing plan to the Administrative Agent.

               SECTION 5.15.  Ownership of Core Subsidiaries. The Borrower shall
                              ------------------------------
at all times own, directly or indirectly through a Core Subsidiary, more than
50% of the voting and economic interests in each Core Subsidiary.

                                  ARTICLE VI

                              Negative Covenants
                              ------------------

          Until the Commitments have expired or terminated and the principal of
and interest on each Loan and all fees payable hereunder have been paid in full
and all Letters of Credit have expired or terminated and all LC Disbursements
shall have been reimbursed, the Borrower covenants and agrees with the Lenders
that:

               SECTION 6.01.  Indebtedness
                              ------------

               (a)    The Borrower will not, and will not permit any Core
Subsidiary to, create, incur, assume or permit to exist any Indebtedness,
unless, after giving effect to the incurrence of such Indebtedness (as if
incurred and applied on the first day of any period for which the Cash Flow to
Fixed Charges Ratio is calculated pursuant to the following clause (i) or (ii),
as the case may be), the making of any Restricted Payments to be made in
connection therewith, the receipt and application of the proceeds thereof and
the consummation of any other transactions related thereto:

                    (i) the Cash Flow to Fixed Charges Ratio for the previous
     four fiscal quarters of the Borrower shall be equal to or greater than 2.5
     to 1.0, and

                                       53
<PAGE>

           (ii) the projected Cash Flow to Fixed Charges Ratio (determined on a
     pro forma basis which is (A) consistent with the then applicable power
     marketing plan delivered pursuant to Section 4.01(j) or 5.14, as applicable
                                          ---------------    ----
     or, (B) if no such power marketing plan is available, consistent with
     projections prepared by the Borrower in good faith based on assumptions
     consistent in all material respects with the relevant contracts and
     agreements, historical operations, and the Borrower's good faith
     projections of future revenues and projections of operating and maintenance
     expenses for the Borrower and its Core Subsidiaries in light of the then
     existing or reasonably expected regulatory and market environments in the
     markets in which its assets is or will be operated and upon the assumption
     that there will be no early redemption or prepayments of Indebtedness other
     than early redemptions or prepayments occurring concurrently with such
     incurrence of Indebtedness) for each year during the term in which such new
     Indebtedness is outstanding shall be equal to or greater than 2.5 to 1.0,

in each case as certified by a Financial Officer; provided, however, that no
Indebtedness shall be incurred pursuant to this clause (a) if a Default shall
have occurred and be continuing or would result from the incurrence of such
Indebtedness.

     (b)    Notwithstanding the provisions of clause (a) of this Section 6.01,
                                                                 ------------
the Borrower and its Core Subsidiaries may incur the following Indebtedness at
any time:

           (i)    the Indebtedness hereunder and any refinancing thereof;

           (ii)   the Lease Debt;

           (iii)  Indebtedness under the Existing Credit Agreement;

           (iv)   commercial paper issued by the Borrower which has been
     purchased based on the availability of all or a portion of the commitments
     then outstanding under the Existing Credit Agreement;

           (v)    Indebtedness up to an amount equal to, at any time
     outstanding, (A) $150,000,000 less (B) the then outstanding principal
     amount of the outstanding commitments under the Existing Credit Agreement
     incurred for the purpose of financing all or any part of the cost of the
     construction, installation, lease, development or improvement of any assets
     used or useful in a Permitted Business;

           (vi)   Subordinated Indebtedness (other than Subordinated
     Indebtedness issued to Affiliates of the Borrower) in an amount up to
     $25,000,000;

           (vii)  Subordinated Indebtedness issued to Affiliates of the Borrower
     in an amount up to $100,000,000;

           (viii) Non-Recourse Indebtedness incurred by Additional Subsidiaries
     for the purpose of financing all or any part of the costs of construction,
     installation, lease, development or improvement of any assets used or
     useful in a Permitted Business, provided that if any such Indebtedness
     ceases to be Non-Recourse Indebtedness of an

                                       54
<PAGE>

     Additional Subsidiary, such event shall be deemed to constitute an
     incurrence of Indebtedness by a Core Subsidiary that was not permitted by
     this clause (viii); and

              (ix) Indebtedness incurred in exchange for, or the net proceeds of
     which are used to refund, refinance or replace Indebtedness permitted to be
     incurred pursuant to Section 6.01(a), provided that (A) the principal
                          ---------------
     amount of such new Indebtedness shall not exceed the principal amount of
     the Indebtedness so refinanced plus a reasonable premium in connection with
     the redemption or repurchase of such refinanced Indebtedness, (B) the final
     maturity date of such new Indebtedness shall not be earlier than the final
     maturity date of the Indebtedness so refinanced and (C) the average life of
     such new Indebtedness shall be equal to or greater than the average life of
     the Indebtedness so refinanced;

          (c)    provided, however, that no Indebtedness shall be incurred
     pursuant to clause (b) if a Default shall have occurred and be continuing
     or would result from the incurrence of such Indebtedness.

          SECTION 6.02.  Liens. The Borrower will not, and will not permit any
                         -----
Core Subsidiary to, create, incur, assume or permit to exist any Lien on any
property or asset now owned or hereafter acquired by it, or assign or sell any
income or revenues (including accounts receivable) or rights in respect of any
thereof except Permitted Liens.

          SECTION 6.03.  Fundamental Changes.
                         -------------------

          (a)    The Borrower will not and will not permit any Core Subsidiary
to, merge into or consolidate with any other Person, or permit any other Person
to merge into or consolidate with it, or liquidate or dissolve, except that, if
at the time thereof and immediately after giving effect thereto no Default shall
have occurred and be continuing (i) any Core Subsidiary may merge into the
Borrower in a transaction in which the Borrower is the surviving corporation,
(ii) any Subsidiary may merge into any Subsidiary in a transaction in which the
surviving entity is a Subsidiary and, if any party to such merger is a Core
Subsidiary, is a Core Subsidiary, and (iii) any Subsidiary may liquidate or
dissolve if the Borrower determines in good faith that such liquidation or
dissolution is in the best interests of the Borrower and its Subsidiaries, taken
as a whole, and is not materially disadvantageous to the Lenders; provided that
any such merger involving a Person that is not a wholly-owned Subsidiary
immediately prior to such merger shall not be permitted unless also permitted by
Section 6.05.
------------

          (b)    The Borrower will not, and will not permit any of its
Subsidiaries to, engage to any material extent in any business other than a
Permitted Business.

          SECTION 6.04.  Asset Sales. The Borrower will not, and will not permit
                         -----------
any of its Core Subsidiaries to, sell or otherwise dispose of any assets
(including any issuance or sale by the Borrower or any of its Core Subsidiaries
of Equity Interests in any of their respective Core Subsidiaries and any
designation of a Core Subsidiary as an Additional Subsidiary), if the aggregate
net book value of all such asset sales consummated since the Closing Date would
exceed 15% of the Borrower's Consolidated Tangible Net Assets as of most
recently ended fiscal

                                       55
<PAGE>

quarter; provided that the following asset sales shall not be subject to such
limitation and shall not be included in such calculation of net book value:

           (i)      dispositions of worn out, obsolete or surplus items of
     equipment which are not necessary in the conduct of the Borrower's or its
     Core Subsidiaries' businesses;

           (ii)     asset sales the proceeds of which are invested by the
     Borrower or any of its Core Subsidiaries in a Permitted Business or used by
     the Borrower or any of its Core Subsidiaries to repay other existing
     Indebtedness of the Borrower or any of its Core Subsidiaries;

           (iii)    transfers of assets among the Borrower and any of its
     wholly-owned Core Subsidiaries;

           (iv)     sales of inventory (including, but not limited to, fuel and
     coal), products or obsolete items and other similar dispositions and sales
     of power in the ordinary course of business;

           (v)      a transfer of ownership of the Kerr hydroelectric generating
     facility by the Borrower or any Core Subsidiary to the Confederated Salish
     and Kootenai Tribes or any successor in interest;

           (vi)     sales of assets required to be made pursuant to any change
     in law, regulation or any imposition by the FERC or any other Governmental
     Authority having or claiming jurisdiction over the Borrower, its Core
     Subsidiaries or the Montana Assets of any conditions or requirements;

           (vii)    an issuance of Equity Interests by a wholly-owned Core
     Subsidiary to the Borrower or to another wholly-owned Core Subsidiary;

           (viii)   a sale or liquidation of Cash Equivalents in the ordinary
     course of business;

           (ix)     a Restricted Payment that is made in cash or Cash
     Equivalents that is permitted under Section 6.05; and
                                         ------------

           (x)      Permitted Investments other than those made in Additional
     Subsidiaries.

        SECTION 6.05.  Restricted Payments; Certain Payments of Indebtedness.
                       -----------------------------------------------------
The Borrower will not, and will not permit any of its Core Subsidiaries to, make
any Restricted Payment, unless:

        (a)    such Restricted Payment is a payment of interest on Subordinated
Indebtedness that (1) is due and payable and (2) when made is permitted to be
made under the subordination terms contained in the instrument evidencing such
Subordinated Indebtedness,

                                       56
<PAGE>

        (b)    such Restricted Payment is a payment of principal of Subordinated
Indebtedness that (1) is due and payable, (2) was counted as Fixed Charges at
the time of the incurrence of such Subordinated Indebtedness pursuant to Section
                                                                         -------
6.01 and (3) when made is permitted to be made under the subordination terms
----
contained in the instrument evidencing such Subordinated Indebtedness,

        (c)    at the time of and after giving effect to such Restricted
Payment,

           (i)   no Default shall have occurred and be continuing or shall
     result from the making of such Restricted Payment,

           (ii)  the Cash Flow to Fixed Charges Ratio for the previous four
     fiscal quarters of the Borrower is equal to or greater than 1.7 to 1.0, and

           (iii) The projected Cash Flow to Fixed Charges Ratio (determined on
     a pro forma basis which is (A) consistent with the then applicable power
     marketing plan delivered pursuant to Section 4.01(j) or 5.14, as
                                          ---------------    ----
     applicable, or (B) if no such power marketing plan is available, consistent
     with projections prepared by the Borrower in good faith based on
     assumptions consistent in all material respects with the relevant contracts
     and agreements, historical operations, and the Borrower's good faith
     projections of future revenues and projections of operating and maintenance
     expenses for the Borrower and its Core Subsidiaries in light of the then
     existing or reasonably expected regulatory and market environments in the
     markets in which its assets is or will be operated and upon the assumption
     that there will be no early redemption or prepayments of Indebtedness other
     than early redemptions or prepayments occurring concurrently with such
     incurrence of Indebtedness) for each of the two following periods of four
     full fiscal quarters shall be equal to or greater than 1.7 to 1.0;

provided further that, so long as no Default or Event of Default shall have
occurred and be continuing or shall result from the making of such Restricted
Payment, this Section 6.05 shall not prohibit the redemption, repurchase,
              ------------
retirement, defeasance or other acquisition of any Subordinated Indebtedness of
the Borrower or of any Equity Interests in the Borrower in exchange for, or out
of the Net Proceeds of the substantially concurrent sale (other than to a
Subsidiary) of, Equity Interests in the Borrower.

        SECTION 6.06.  Transactions with Affiliates. The Borrower will not, and
                       ----------------------------
will not permit any of its Core Subsidiaries to, sell, lease, transfer or
otherwise dispose of any of its properties or assets to, or purchase any
property or assets from, or enter into or make or amend any contract, agreement,
understanding, loan, advance or guarantee with, to or for the benefit of, any
Affiliate (other than transactions contemplated by any agreement entered into
between the Borrower or any of its Core Subsidiaries and any of their respective
Affiliates in effect on the Closing Date) unless such transaction or series of
transactions is on terms that are no less favorable to the Borrower or such Core
Subsidiary than would be available in a comparable transaction with an unrelated
third party.

        SECTION 6.07.  Amendment of Material Documents. The Borrower will not,
                       -------------------------------
and will not permit any Core Subsidiary to, materially amend or modify any of
its rights under its

                                       57
<PAGE>

certificate of incorporation, by-laws or other organizational documents. The
Borrower will not, and will not permit any Core Subsidiary to, enter into any
material amendment, modification or assignment of, or waiver of rights under,
any Material Agreement, in each case which is material to the Lenders as
determined by the Required Lenders.

               SECTION 6.08.  Guarantees and Indemnities. The Borrower will not,
                              --------------------------
and will not permit any of its Core Subsidiaries to, be or become liable under
any Guarantee (other than a Guarantee permitted under Section 6.01) or any
                                                      ------------
indemnity obligation (other than obligations incurred in the ordinary course of
business or in connection with the Transactions).

               SECTION 6.09.  Fiscal Year. The Borrower will not, and will not
                              -----------
permit any of its Core Subsidiaries to, change its fiscal year from that in
effect on the Closing Date.

               SECTION 6.10.  Ownership of Core Subsidiaries. The Borrower will
                              ------------------------------
not, and will not permit any Core Subsidiary to, engage in any transaction which
results in any Core Subsidiary ceasing to be a Subsidiary following the
consummation of such transaction, unless (a) such transaction is permitted under
Section 6.04 and (b) the Borrower does not own, directly or indirectly, any of
------------
the Equity Interests of such Subsidiary following the consummation of such
transaction.

               SECTION 6.11.  Debt to Capital Ratio. The Borrower will not
                              ---------------------
permit the Debt to Capital Ratio to exceed 0.6 to 1.0.

               SECTION 6.12.  Additional Subsidiaries and Core Subsidiaries. The
                              ---------------------------------------------
Borrower may designate any Subsidiary as an Additional Subsidiary if:

               (a)    such designation is in compliance with Section 6.05;
                                                             ------------

               (b)    after giving effect to such designation, such Subsidiary
does not own, directly or indirectly, 50% or more of the Equity Interests in any
Core Subsidiary;

               (c)    such Subsidiary has no Indebtedness other than Non-
Recourse Indebtedness;

               (d)    such Subsidiary is not party to any agreement, contract,
arrangement or understanding with the Borrower or any Core Subsidiary other than
any such agreement, contract, arrangement or understanding the terms of which
are no less favorable to the Borrower or such Core Subsidiary than the terms
that the Borrower or such Core Subsidiary could obtain at the time from Persons
who are not Affiliates of the Borrower or such Core Subsidiary;

               (e)    such Subsidiary is a Person with respect to which neither
the Borrower nor any of its Core Subsidiaries has any direct or indirect
obligation (i) to subscribe for additional Equity Interests (unless the amount
of such subscription could be made as a Restricted Payment) or (ii) to maintain
or preserve such Person's financial condition or to cause such Person to achieve
any specified levels of operating results; and

               (f)    such Subsidiary has not Guaranteed or otherwise directly
or indirectly provided credit support for any Indebtedness of the Borrower or
any of its Core Subsidiaries.

                                       58
<PAGE>

The Borrower may designate an Additional Subsidiary as a Core Subsidiary if (a)
the Indebtedness of such Additional Subsidiary would have been permitted under
Section 6.01(a) if such designation had been made on the first day of the period
---------------
referred to in Section 6.01(a)(i); and (b) no Default shall have occurred and be
               ------------------
continuing or shall result from such designation.  Any designation of a Core
Subsidiary as an Additional Subsidiary, and any designation of an Additional
Subsidiary as a Core Subsidiary, shall be evidenced by filing with the
Administrative Agent a certified copy of the resolution of the board of
directors of the Borrower giving effect to such designation and an officer's
certificate of the Borrower certifying that such designation complies with the
applicable requirements set forth in this Section 6.12.  Any Core Subsidiary
                                          ------------
designated as an Additional Subsidiary in accordance with this Section 6.12
                                                               ------------
shall be released from its obligations under the Subsidiary Guarantee Agreement.

               SECTION 6.13.  Letters of Credit. The Borrower will not, and will
                              -----------------
not permit any Core Subsidiary to, enter into any agreement, document or
instrument pursuant to which the Borrower or any Core Subsidiary is obligated to
provide any letter of credit, the stated amount of which could materially
increase other than (i) fixed price forward contracts that require physical
delivery of a commodity or (ii) derivative financial instruments entered into to
manage risks associated with energy price fluctuations that require a letter of
credit (or other financial assurances that can be provided in the form of a
letter of credit).

                                  ARTICLE VII

                               Events of Default
                               -----------------

          If any of the following events ("Events Of Default") shall occur:

          (a)    the Borrower or any Core Subsidiary shall fail to pay any
principal of any Loan or any reimbursement obligation in respect of any LC
Disbursement when and as the same shall become due and payable, whether at the
due date thereof or at a date fixed for prepayment thereof or otherwise;

          (b)    the Borrower or any Core Subsidiary shall fail to pay any
interest on any Loan or any fee or any other amount (other than an amount
referred to in clause (a) of this Article) payable under this Agreement or any
other Loan Document, when and as the same shall become due and payable, and such
failure shall continue unremedied for a period of 5 Business Days;

          (c)    any representation or warranty made or deemed made by or on
behalf of any Loan Party in or in connection with any Loan Document or any
amendment or modification thereof or waiver thereunder, or in any report,
certificate, financial statement or other document furnished pursuant to or in
connection with any Loan Document or any amendment or modification thereof or
waiver thereunder, shall prove to have been incorrect in any material respect
when made or deemed made;

                                       59
<PAGE>

          (d)    the Borrower or any Core Subsidiary shall fail to observe or
perform any covenant, condition or agreement contained in Section 5.02, 5.04
                                                          ------------  ----
(with respect to the existence of such Loan Party) or 5.10 or in Article VI;
                                                      ----       ----------

          (e)    any Loan Party shall fail to observe or perform any covenant,
condition or agreement contained in any Loan Document (other than those
specified in clause (a), (b), (d) or (o) of this Article), and such failure
shall continue unremedied for a period of 30 days after notice thereof from the
Administrative Agent to the Borrower (which notice will be given at the request
of any Lender);

          (f)    the Borrower or any Core Subsidiary shall fail to make any
payment of principal or interest (regardless of amount) in respect of any
Material Indebtedness, when and as the same shall become due and payable after
the expiration of any applicable grace period;

          (g)    any event or condition which occurs and continues after the
expiration of any applicable grace period that (i) results in any Material
Indebtedness becoming due prior to its scheduled maturity or amortization or
(ii) enables or permits the holder or holders of any Material Indebtedness or
any trustee or agent on its or their behalf to cause any Material Indebtedness
to become due, or to require the prepayment, repurchase, redemption or
defeasance thereof, prior to its scheduled maturity or amortization;

          (h)    an involuntary proceeding shall be commenced or an involuntary
petition shall be filed seeking (i) liquidation, reorganization or other relief
in respect of any Loan Party or its debts, or of a substantial part of its
assets, under any Federal, state or foreign bankruptcy, insolvency, receivership
or similar law now or hereafter in effect or (ii) the appointment of a receiver,
trustee, custodian, sequestrator, conservator or similar official for any Loan
Party or for a substantial part of its assets, and, in any such case, such
proceeding or petition shall continue undismissed for 60 days or an order or
decree approving or ordering any of the foregoing shall be entered;

          (i)    any Loan Party shall (i) voluntarily commence any proceeding or
file any petition seeking liquidation, reorganization or other relief under any
Federal, state or foreign bankruptcy, insolvency, receivership or similar law
now or hereafter in effect, (ii) consent to the institution of, or fail to
contest in a timely and appropriate manner, any proceeding or petition described
in clause (h) of this Article, (iii) apply for or consent to the appointment of
a receiver, trustee, custodian, sequestrator, conservator or similar official
for any Loan Party or for a substantial part of its assets, (iv) file an answer
admitting the material allegations of a petition filed against it in any such
proceeding, (v) make a general assignment for the benefit of creditors or (vi)
take any action for the purpose of effecting any of the foregoing;

          (j)    any Loan Party shall become unable, admit in writing its
inability or fail generally to pay its debts as they become due;

          (k)    one or more judgments for the payment of money in an aggregate
amount in excess of $10,000,000 shall be rendered against the Borrower, any
Subsidiary or any combination thereof and the same shall remain undischarged for
a period of 30 consecutive days during which execution shall not be effectively
stayed, or any action shall be legally taken by a

                                       60
<PAGE>

judgment creditor to attach or levy upon any assets of the Borrower or any
Subsidiary to enforce any such judgment;

          (l)  an ERISA Event shall have occurred that, in the opinion of the
Required Lenders, when taken together with all other ERISA Events that have
occurred, could reasonably be expected to result in a Material Adverse Effect;

          (m)  the Subsidiary Guarantee Agreement shall fail to be in full force
and effect, enforceable against the parties thereto in accordance with its
terms, or any party thereto shall be released from any of its obligations
thereunder except as expressly permitted under Section 6.12 hereof;
                                               ------------

          (n)  a Change in Control shall occur; or

          (o)  any default under Section 2 of the Parent Letter Agreement;
                                 ---------

then, and in every such event (other than an event with respect to the Borrower
described in clause (h) or (i) of this Article), and at any time thereafter
during the continuance of such event, the Administrative Agent may, and at the
request of the Required Lenders shall, by notice to the Borrower, take either or
both of the following actions, at the same or different times: (i) terminate the
Commitments, and thereupon the Commitments shall terminate immediately, and (ii)
declare the Loans then outstanding to be due and payable in whole (or in part,
in which case any principal not so declared to be due and payable may thereafter
be declared to be due and payable), and thereupon the principal of the Loans so
declared to be due and payable, together with accrued interest thereon and all
fees and other obligations of the Borrower accrued hereunder, shall become due
and payable immediately, without presentment, demand, protest or other notice of
any kind, all of which are hereby waived by the Borrower (except as expressly
provided above in this Section); and in case of any event with respect to the
Borrower described in clause (h) or (i) of this Article, the Commitments shall
automatically terminate and the principal of the Loans then outstanding,
together with accrued interest thereon and all fees and other obligations of the
Borrower accrued hereunder, shall automatically become due and payable, without
presentment, demand, protest or other notice of any kind, all of which are
hereby waived by the Borrower.

          Furthermore, upon the occurrence of any Event of Default, the
Administrative Agent may direct the Borrower to pay (and the Borrower agrees
that upon receipt of such notice by the Borrower, or upon the occurrence of an
Event of Default under either clause (h) or (i) above they shall immediately
pay) to the Administrative Agent additional cash, to be held by the
Administrative Agent as cash collateral, for the benefit of the Lenders, as
additional security for the LC Exposure in an amount equal to the outstanding LC
Exposure in accordance with Section 2.02(j).
                            ---------------

                                       61
<PAGE>

                                 ARTICLE VIII

                           The Administrative Agent
                           ------------------------

          Each of the Lenders and the Issuing Bank hereby irrevocably appoints
the Administrative Agent as its agent and authorizes the Administrative Agent to
take such actions on its behalf and to exercise such powers as are delegated to
the Administrative Agent by the terms of the Loan Documents, together with such
actions and powers as are reasonably incidental thereto.

          The bank serving as Administrative Agent hereunder shall have the same
rights and powers in its capacity as a Lender as any other Lender and may
exercise the same as though it were not the Administrative Agent, and such bank
and its Affiliates may accept deposits from, lend money to and generally engage
in any kind of business with the Borrower or any Subsidiary or other Affiliate
thereof as if it were not the Administrative Agent hereunder.

          The Administrative Agent shall not have any duties or obligations
except those expressly set forth in the Loan Documents.  Without limiting the
generality of the foregoing, (a) the Administrative Agent shall not be subject
to any fiduciary or other implied duties, regardless of whether a Default has
occurred and is continuing, (b) the Administrative Agent shall not have any duty
to take any discretionary action or exercise any discretionary powers, except
discretionary rights and powers expressly contemplated by the Loan Documents
that such Agent is required to exercise in writing by the Required Lenders (or
such other number or percentage of the Lenders as shall be necessary under the
circumstances as provided in Section 9.02), and (c) except as expressly set
                             ------------
forth in the Loan Documents, the Administrative Agent shall not have any duty to
disclose, and shall not be liable for the failure to disclose, any information
relating to the Borrower or any of its Subsidiaries that is communicated to or
obtained by it serving as Administrative Agent or any of its Affiliates in any
capacity.  The Administrative Agent shall not be liable to the Lenders for any
action taken or not taken by it with the consent or at the request of the
Required Lenders (or such other number or percentage of the Lenders as shall be
necessary under the circumstances as provided in Section 9.02) or in the absence
                                                 ------------
of its own gross negligence or willful misconduct.  The Administrative Agent
shall not be deemed to have knowledge of any Default unless and until written
notice thereof is given to the Administrative Agent by the Borrower or a Lender,
and the Administrative Agent shall not be responsible for or have any duty to
ascertain or inquire into (i) any statement, warranty or representation made in
or in connection with any Loan Document, (ii) the contents of any certificate,
report or other document delivered thereunder or in connection therewith, (iii)
the performance or observance of any of the covenants, agreements or other terms
or conditions set forth in any Loan Document, (iv) the validity, enforceability,
effectiveness or genuineness of any Loan Document or any other agreement,
instrument or document, or (v) the satisfaction of any condition set forth in
Article IV or elsewhere in any Loan Document, other than to confirm receipt of
----------
items expressly required to be delivered to the Administrative Agent.

          The Administrative Agent shall be entitled to rely upon, and shall not
incur any liability for relying upon, any notice, request, certificate, consent,
statement, instrument, document or other writing believed by it to be genuine
and to have been signed or sent by the proper Person.  The Administrative Agent
also may rely upon any statement made to it orally or

                                       62
<PAGE>

by telephone and believed by it to be made by the proper Person, and shall not
incur any liability for relying thereon. The Administrative Agent may consult
with legal counsel (who may be counsel for the Borrower), independent
accountants and other experts selected by it, and shall not be liable to the
Lenders for any action taken or not taken by it in accordance with the advice of
any such counsel, accountants or experts.

          The Administrative Agent may perform any and all its duties and
exercise its rights and powers by or through any one or more sub-agents
appointed by the Administrative Agent.  The Administrative Agent and any such
sub-agent may perform any and all its duties and exercise its rights and powers
through their respective Related Parties.  The exculpatory provisions of the
preceding paragraphs shall apply to any such sub-agent and to the Related
Parties of each Administrative Agent and any such sub-agent, and shall apply to
their respective activities in connection with the syndication of the credit
facilities provided for herein as well as activities as Administrative Agent.

          Subject to the appointment and acceptance of a successor to the
Administrative Agent as provided in this paragraph, the Administrative Agent may
resign at any time by notifying the Lenders, the Issuing Bank and the Borrower.
Upon any such resignation, the Required Lenders shall have the right, with the
prior written consent of the Borrower (such consent not to be unreasonably
withheld) unless a Default shall have occurred and be continuing, to appoint a
successor.  If no successor shall have been so appointed by the Required Lenders
and shall have accepted such appointment within 30 days after the retiring
Administrative Agent gives notice of its resignation, then the retiring
Administrative Agent may, on behalf of the Lenders and the Issuing Bank, appoint
a successor Administrative Agent which shall be a bank with an office in New
York, New York, or an Affiliate of any such bank.  Upon the acceptance of its
appointment as an Administrative Agent hereunder by a successor, such successor
shall succeed to and become vested with all the rights, powers, privileges and
duties of the retiring Administrative Agent, and the retiring Administrative
Agent shall be discharged from its duties and obligations hereunder.  The fees
payable by the Borrower to a successor Administrative Agent shall be, without
duplication, the same as those payable to its predecessor unless otherwise
agreed between the Borrower and such successor.  After an Administrative Agent's
resignation hereunder, the provisions of this Article and Section 9.03 shall
                                                          ------------
continue in effect for the benefit of such retiring Administrative Agent, its
sub-agents and their respective Related Parties in respect of any actions taken
or omitted to be taken by any of them while it was acting as Administrative
Agent.

          Each Lender acknowledges that it has, independently and without
reliance upon the Administrative Agent or any other Lender and based on such
documents and information as it has deemed appropriate, made its own credit
analysis and decision to enter into this Agreement.  Each Lender also
acknowledges that it will, independently and without reliance upon the
Administrative Agent or any other Lender and based on such documents and
information as it shall from time to time deem appropriate, continue to make its
own decisions in taking or not taking action under or based upon this Agreement,
any other Loan Document or related agreement or any document furnished hereunder
or thereunder.

                                       63
<PAGE>

                                  ARTICLE IX

                                 Miscellaneous
                                 -------------

          SECTION 9.01.  Notices. Except in the case of notices and other
                         -------
communications expressly permitted to be given by telephone, all notices and
other communications provided for herein shall be in writing and shall be
delivered by hand or overnight courier service, mailed by certified or
registered mail or sent by telecopy, as follows:

          (a)  if to the Borrower, to it at 303 North Broadway, Suite 400,
     Billings, Montana 59101 Attention of General Counsel (Telecopy No. (406)
     869-5149);

          (b)  if to the Administrative Agent, to The Chase Manhattan Bank, Loan
     and Agency Services Group, One Chase Manhattan Plaza, 8th Floor, New York,
     New York 10081, Attention of Rob Bowen (Telecopy No. (212) 552-7777), with
     a copy to The Chase Manhattan Bank, 270 Park Avenue, 21/st/ Floor, New
     York, New York 10017, Attention of Jaimin Patel (Telecopy No. (212) 270-
     2101);

          (c)  if to the Issuing Bank, to The Chase Manhattan Bank, as Issuing
     Bank, Standby Letter of Credit Department, 4 Chase MetroTech Center, 8/th/
     Floor, Brooklyn, New York 11245, Attention of Roshdy Botros (Telecopy No.
     (718) 242-6501, Phone: (718) 2424-5045) with a copy to The Chase Manhattan
     Bank, 270 Park Avenue, 21/st/ Floor, New York, New York 10017, Attention of
     Jaimin Patel (Telecopy No. (212) 270-2101); and

          (d)  if to any other Lender, to it at its address (or telecopy number)
     set forth in its Administrative Questionnaire.

Any party hereto may change its address or telecopy number for notices and other
communications hereunder by notice to the other parties hereto.  All notices and
other communications given to any party hereto in accordance with the provisions
of this Agreement shall be deemed to have been given on the date of receipt.

          SECTION 9.02.  Waivers; Amendments.
                         -------------------

          (a)  No failure or delay by the Administrative Agent, the Issuing Bank
or any Lender in exercising any right or power hereunder or under any other Loan
Document shall operate as a waiver thereof, nor shall any single or partial
exercise of any such right or power, or any abandonment or discontinuance of
steps to enforce such a right or power, preclude any other or further exercise
thereof or the exercise of any other right or power. The rights and remedies of
the Administrative Agent, the Issuing Bank and the Lenders hereunder and under
the other Loan Documents are cumulative and are not exclusive of any rights or
remedies that they would otherwise have. No waiver of any provision of any Loan
Document or consent to any departure by any Loan Party therefrom shall in any
event be effective unless the same shall be permitted by paragraph (b) of this
Section, and then such waiver or consent shall be effective only in the specific
instance and for the purpose for which given. Without limiting the generality of
the foregoing, the making of a Loan or issuance of a Letter of Credit shall not
be construed as a

                                       64
<PAGE>

waiver of any Default, regardless of whether the Administrative Agent, any
Lender or the Issuing Bank may have had notice or knowledge of such Default at
the time.

          (b)  Neither this Agreement nor any other Loan Document nor any
provision hereof or thereof may be waived, amended or modified except, in the
case of this Agreement, pursuant to an agreement or agreements in writing
entered into by the Borrower and the Required Lenders or, in the case of any
other Loan Document, pursuant to an agreement or agreements in writing entered
into by the Administrative Agent and the Loan Party or Loan Parties that are
parties thereto, in each case with the consent of the Required Lenders; provided
that no such agreement shall:

               (i)   increase the Commitment of any Lender without the written
     consent of such Lender,

               (ii)  reduce the principal amount of any Loan or LC Disbursement
     or reduce the rate of interest thereon, or reduce any fees payable
     hereunder, without the written consent of each Lender affected thereby,

               (iii) postpone the maturity of any Loan, or the required date of
     reimbursement of any LC Disbursement, or any date for the payment of any
     interest or fees payable hereunder, or reduce the amount of, waive or
     excuse any such payment, or postpone the scheduled date of expiration of
     any Commitment, without the written consent of each Lender affected
     thereby,

               (iv)  change Section 2.15(b) or (c) in a manner that would alter
                            ---------------    ---
     the pro rata sharing of payments required thereby, without the written
     consent of each Lender,

               (v)   change any of the provisions of this Section or the
     percentage set forth in the definition of "Required Lenders" or any other
     provision of any Loan Document specifying the number or percentage of
     Lenders required to waive, amend or modify any rights thereunder or make
     any determination or grant any consent thereunder, without the written
     consent of each Lender, or

               (vi)  release any Core Subsidiary from its obligations under the
     Subsidiary Guarantee Agreement (other than as set forth in Section 6.12),
                                                                ------------
     or limit its liability in respect of such obligations, without the written
     consent of each Lender,

provided further that (A) no such agreement shall amend, modify or otherwise
affect the rights or duties of the Administrative Agent or the Issuing Bank
without the prior written consent of the Administrative Agent or the Issuing
Bank, as the case may be.  Notwithstanding the foregoing, any provision of this
Agreement may be amended by an agreement in writing entered into by the
Borrower, the Required Lenders, the Administrative Agent and the Issuing Bank if
(i) by the terms of such agreement the Commitment of each Lender not consenting
to the amendment provided for therein shall terminate upon the effectiveness of
such amendment and (ii) at the time such amendment becomes effective, each
Lender not consenting thereto receives payment in full of the principal of and
interest accrued on each Loan made by it and all other amounts owing to it or
accrued for its account under this Agreement.

                                       65
<PAGE>

          SECTION 9.03.  Expenses; Indemnity; Damage Waiver.
                         ----------------------------------

          (a)     The Borrower shall pay:

               (i)   all reasonable out-of-pocket expenses incurred by the
     Administrative Agent, including the reasonable fees, charges and
     disbursements of counsel for the Administrative Agent, the preparation and
     administration of the Loan Documents or any amendments, modifications or
     waivers of the provisions thereof (whether or not the transactions
     contemplated hereby or thereby shall be consummated),

               (ii)  all reasonable out-of-pocket expenses incurred by the
     Issuing Bank in connection with the issuance, amendment, renewal or
     extension of any Letter of Credit or any demand for payment thereunder and

               (iii) all out-of-pocket expenses incurred by the Administrative
     Agent, the Issuing Bank or any Lender, including the fees, charges and
     disbursements of any counsel for the Administrative Agent, the Issuing Bank
     or any Lender, in connection with the enforcement or protection of its
     rights in connection with the Loan Documents, including its rights under
     this Section, or in connection with the Loans made or Letters of Credit
     issued hereunder, including all such out-of-pocket expenses incurred during
     any workout, restructuring or negotiations in respect of such Loans or
     Letters of Credit.

          (b)     The Borrower shall indemnify the Administrative Agent, the
Issuing Bank, each Lender, and each Related Party of any of the foregoing
Persons (each such Person being called an "Indemnitee") against, and hold each
Indemnitee harmless from, any and all losses, claims, damages, liabilities and
related expenses, including the reasonable fees, charges and disbursements of
any counsel for any Indemnitee, whether or not suit is brought, incurred by or
asserted against any Indemnitee arising out of, in connection with, or as a
result of any actual or prospective claim, litigation, investigation or
proceeding relating to (i) the execution or delivery of any Loan Document or any
other agreement or instrument contemplated hereby, the performance by the
parties to the Loan Documents of their respective obligations thereunder or the
consummation of the Transactions or any other transactions contemplated hereby,
(ii) any Loan or Letter of Credit or the use of the proceeds therefrom
(including any refusal by the Issuing Bank to honor a demand for payment under a
Letter of Credit if the documents presented in connection with such demand do
not strictly comply with the terms of such Letter of Credit), or (iii) any
actual or alleged presence or release of Hazardous Materials on or from any
property currently or formerly owned or operated by the Borrower or any of its
Subsidiaries, or any Environmental Liability related in any way to the Borrower
or any of its Subsidiaries, whether based on contract, tort or any other theory
and regardless of whether any Indemnitee is a party thereto; provided that (i)
such indemnity shall not, as to any Indemnitee, be available to the extent that
such losses, claims, damages, liabilities or related expenses are determined by
a court of competent jurisdiction to have resulted from the gross negligence,
bad faith or willful misconduct of such Indemnitee.

          (c)     To the extent that the Borrower fails to pay any amount
required to be paid by it to the Administrative Agent or the Issuing Bank under
paragraph (a) or (b) of this Section, each Lender severally agrees to pay to the
affected Administrative Agent or the Issuing Bank, as

                                       66
<PAGE>

the case may be, such Lender's pro rata share (determined as of the time that
the applicable unreimbursed expense or indemnity payment is sought) of such
unpaid amount; provided that the unreimbursed expense or indemnified loss,
claim, damage, liability or related expense, as the case may be, was incurred by
or asserted against the affected Agent or the Issuing Bank in its capacity as
such. For purposes hereof, a Lender's "pro rata share" shall be determined based
upon its share of the sum of the total Committed Exposures and unused
Commitments at the time.

          (d)     To the extent permitted by applicable law, the Borrower shall
not assert, and hereby waives, any claim against any Indemnitee, on any theory
of liability, for special, indirect, consequential or punitive damages (as
opposed to direct or actual damages) arising out of, in connection with, or as a
result of, this Agreement or any agreement or instrument contemplated hereby,
the Transactions, any Loan or Letter of Credit or the use of the proceeds
thereof.

          (e)     All amounts due under this Section shall be payable promptly
after written demand therefor.

          SECTION 9.04.  Successors and Assigns.
                         ----------------------

          (a)     The provisions of this Agreement shall be binding upon and
inure to the benefit of the parties hereto and their respective successors and
assigns permitted hereby (including any Affiliate of the Issuing Bank that
issues any Letter of Credit), except that the Borrower may not assign or
otherwise transfer any of its rights or obligations hereunder without the prior
written consent of each Lender (and any attempted assignment or transfer by the
Borrower without such consent shall be null and void). Nothing in this
Agreement, expressed or implied, shall be construed to confer upon any Person
(other than the parties hereto, their respective successors and assigns
permitted hereby (including any Affiliate of the Issuing Bank that issues any
Letter of Credit) and, to the extent expressly contemplated hereby, the Related
Parties of each of the Administrative Agent, the Issuing Bank and the Lenders)
any legal or equitable right, remedy or claim under or by reason of this
Agreement.

          (b)     Any Lender may assign to one or more banks or other financial
institutions all or a portion of its rights and obligations under this Agreement
(including all or a portion of its Commitment and the Loans at the time owing to
it); provided that:

               (i)   except in the case of an assignment to a Lender or an
     Affiliate of a Lender, each of the Borrower, the Administrative Agent and
     the Issuing Bank must give their prior written consent to such assignment
     (which consent shall not be unreasonably withheld),

               (ii)  except in the case of an assignment to a Lender or an
     Affiliate of a Lender or an assignment of the entire remaining amount of
     the assigning Lender's Commitment or Loans, the amount of the Commitment or
     Loans of the assigning Lender subject to each such assignment (determined
     as of the date the Assignment and Acceptance with respect to such
     assignment is delivered to the Administrative Agent)

                                       67
<PAGE>

     shall not be less than $5,000,000, unless each of the Borrower and the
     Administrative Agent otherwise consent,

               (iii) each partial assignment shall be made as an assignment of a
     proportionate part of all the assigning Lender's rights and obligations
     under this Agreement,

               (iv)  the parties to each assignment shall execute and deliver to
     the Administrative Agent an Assignment and Acceptance, together with a
     processing and recordation fee of $3,500, and

               (v)   the assignee, if it shall not be a Lender, shall deliver to
     the Administrative Agent an Administrative Questionnaire;

and provided further that any consent of the Borrower otherwise required under
this paragraph shall not be required if an Event of Default under clause (h) or
(i) of Article VII has occurred and is continuing.  Subject to acceptance and
       -----------
recording thereof pursuant to paragraph (d) of this Section, from and after the
effective date specified in each Assignment and Acceptance the assignee
thereunder shall be a party hereto and, to the extent of the interest assigned
by such Assignment and Acceptance, have the rights and obligations of a Lender
under this Agreement, and the assigning Lender thereunder shall, to the extent
of the interest assigned by such Assignment and Acceptance, be released from its
obligations under this Agreement (and, in the case of an Assignment and
Acceptance covering all of the assigning Lender's rights and obligations under
this Agreement, such Lender shall cease to be a party hereto but shall continue
to be entitled to the benefits of Sections 2.12, 2.13, 2.14 and 9.03).  Any
                                  -------------  ----  ----     ----
assignment or transfer by a Lender of rights or obligations under this Agreement
that does not comply with this paragraph shall be treated for purposes of this
Agreement as a sale by such Lender of a participation in such rights and
obligations in accordance with paragraph (e) of this Section.

          (c)     The Administrative Agent, acting for this purpose as an agent
of the Borrower, shall maintain at one of its offices in The City of New York a
copy of each Assignment and Acceptance delivered to it and a register for the
recordation of the names and addresses of the Lenders, and the Commitment of,
and principal amount of the Loans and LC Disbursements owing to, each Lender
pursuant to the terms hereof from time to time (the "Register"). The entries in
the Register shall be conclusive, and the Borrower, the Administrative Agent,
the Issuing Bank and the Lenders may treat each Person whose name is recorded in
the Register pursuant to the terms hereof as a Lender hereunder for all purposes
of this Agreement, notwithstanding notice to the contrary. The Register shall be
available for inspection by the Borrower, the Issuing Bank and any Lender, at
any reasonable time and from time to time upon reasonable prior notice.

          (d)     Upon its receipt of a duly completed Assignment and Acceptance
executed by an assigning Lender and an assignee, the assignee's completed
Administrative Questionnaire (unless the assignee shall already be a Lender
hereunder), the processing and recordation fee referred to in paragraph (b) of
this Section and any written consent to such assignment required by paragraph
(b) of this Section, the Administrative Agent shall accept such Assignment and
Acceptance and record the information contained therein in the Register. No

                                       68
<PAGE>

assignment shall be effective for purposes of this Agreement unless it has been
recorded in the Register as provided in this paragraph.

          (e)     Any Lender may, without the consent of the Borrower, the
Administrative Agent or the Issuing Bank, sell participations to one or more
banks or other entities (a "Participant") in all or a portion of such Lender's
rights and obligations under this Agreement (including all or a portion of its
Commitment and the Loans owing to it); provided that (i) such Lender's
obligations under this Agreement shall remain unchanged, (ii) such Lender shall
remain solely responsible to the other parties hereto for the performance of
such obligations and (iii) the Borrower, the Administrative Agent, the Issuing
Bank and the other Lenders shall continue to deal solely and directly with such
Lender in connection with such Lender's rights and obligations under this
Agreement. Any agreement or instrument pursuant to which a Lender sells such a
participation shall provide that such Lender shall retain the sole right to
enforce the Loan Documents and to approve any amendment, modification or waiver
of any provision of the Loan Documents; provided that such agreement or
instrument may provide that such Lender will not, without the consent of the
Participant, agree to any amendment, modification or waiver described in the
first proviso to Section 9.02(b) that affects such Participant. Subject to
                 ---------------
paragraph (f) of this Section, the Borrower agrees that each Participant shall
be entitled to the benefits of Sections 2.12, 2.13 and 2.14 to the same extent
                               -------------  ----     ----
as if it were a Lender and had acquired its interest by assignment pursuant to
paragraph (b) of this Section.  To the extent permitted by law, each Participant
also shall be entitled to the benefits of Section 9.08 as though it were a
                                          ------------
Lender, provided that such Participant agrees to be subject to Section 2.15(c)
                                                               ---------------
as though it were a Lender.

          (f)     A Participant shall not be entitled to receive any greater
payment under Section 2.12, 2.13 or 2.14 than the applicable Lender would have
              ------------  ----    ----
been entitled to receive with respect to the participation sold to such
Participant. A Participant that would be a Foreign Lender if it were a Lender
shall not be entitled to the benefits of Section 2.14 unless the Borrower is
                                         ------------
notified of the participation sold to such Participant and such Participant
agrees, for the benefit of the Borrower, to comply with Section 2.14(e) as
                                                        ---------------
though it were a Lender.

          (g)     Any Lender may at any time pledge or assign a security
interest in all or any portion of its rights under this Agreement to secure
obligations of such Lender, including any pledge or assignment to secure
obligations to a Federal Reserve Bank, and this Section shall not apply to any
such pledge or assignment of a security interest; provided that no such pledge
or assignment of a security interest shall release a Lender from any of its
obligations hereunder or substitute any such pledgee or assignee for such Lender
as a party hereto.

          SECTION 9.05.  Survival. All covenants, agreements, representations
                         --------
and warranties made by the Loan Parties in the Loan Documents and in the
certificates or other instruments delivered in connection with or pursuant to
this Agreement or any other Loan Document shall be considered to have been
relied upon by the other parties hereto and shall survive the execution and
delivery of the Loan Documents and the making of any Loans and issuance of any
Letters of Credit, regardless of any investigation made by any such other party
or on its behalf and notwithstanding that the Administrative Agent, the Issuing
Bank or any Lender may have had notice or knowledge of any Default or incorrect
representation or warranty at the time any credit is extended hereunder, and
shall continue in full force and effect as long as the

                                       69
<PAGE>

principal of or any accrued interest on any Loan or any fee or any other amount
payable under this Agreement is outstanding and unpaid or any Letter of Credit
is outstanding and so long as the Commitments have not expired or terminated.
The provisions of Sections 2.12, 2.13, 2.14 and 9.03 and Article VIII shall
                  -------- ----  ----  ----     ----     ------- ----
survive and remain in full force and effect regardless of the consummation of
the transactions contemplated hereby, the repayment of the Loans, the expiration
or termination of the Letters of Credit and the Commitments or the termination
of this Agreement or any provision hereof.

          SECTION 9.06.  Counterparts; Integration; Effectiveness. This
                         ----------------------------------------
Agreement may be executed in counterparts (and by different parties hereto on
different counterparts), each of which shall constitute an original, but all of
which when taken together shall constitute a single contract. This Agreement,
the other Loan Documents and any separate letter agreements with respect to fees
payable to the Administrative Agent constitute the entire contract among the
parties relating to the subject matter hereof and supersede any and all previous
agreements and understandings, oral or written, relating to the subject matter
hereof. This Agreement shall become effective on the Closing Date, and
thereafter shall be binding upon and inure to the benefit of the parties hereto
and their respective successors and assigns. Delivery of an executed counterpart
of a signature page of this Agreement by telecopy shall be effective as delivery
of a manually executed counterpart of this Agreement.

          SECTION 9.07.  Severability. Any provision of this Agreement held to
                         ------------
be invalid, illegal or unenforceable in any jurisdiction shall, as to such
jurisdiction, be ineffective to the extent of such invalidity, illegality or
unenforceability without affecting the validity, legality and enforceability of
the remaining provisions hereof; and the invalidity of a particular provision in
a particular jurisdiction shall not invalidate such provision in any other
jurisdiction.

          SECTION 9.08.  Right of Setoff. If an Event of Default shall have
                         ---------------
occurred and be continuing, each Lender and each of its Affiliates is hereby
authorized at any time and from time to time, to the fullest extent permitted by
law, to set off and apply any and all deposits (general or special, time or
demand, provisional or final) at any time held and other obligations at any time
owing by such Lender or Affiliate to or for the credit or the account of the
Borrower against any of and all the due and owing obligations of the Borrower
now or hereafter existing under this Agreement held by such Lender, irrespective
of whether or not such Lender shall have made any demand under this Agreement
and although such obligations owing by such Lender or Affiliate may be
unmatured. The rights of each Lender under this Section are in addition to other
rights and remedies (including other rights of setoff) which such Lender may
have.

          SECTION 9.09.  Governing Law; Jurisdiction; Consent to Service of
                         --------------------------------------------------
                         Process.
                         -------

          (a)     This Agreement shall be construed in accordance with and
governed by the law of the State of New York.

          (b)     The Borrower hereby irrevocably and unconditionally submits,
for itself and its property, to the nonexclusive jurisdiction of the Supreme
Court of the State of New York sitting in New York County and of the United
States District Court of the Southern District of New York, and any appellate
court from any thereof, in any action or proceeding arising out of or relating
to any Loan Document, or for recognition or enforcement of any judgment, and
each

                                       70
<PAGE>

of the parties hereto hereby irrevocably and unconditionally agrees that all
claims in respect of any such action or proceeding may be heard and determined
in such New York State or, to the extent permitted by law, in such Federal
court. Each of the parties hereto agrees that a final judgment in any such
action or proceeding shall be conclusive and may be enforced in other
jurisdictions by suit on the judgment or in any other manner provided by law.
Nothing in this Agreement or any other Loan Document shall affect any right that
the Administrative Agent, the Issuing Bank or any Lender may otherwise have to
bring any action or proceeding relating to this Agreement or any other Loan
Document against the Borrower or its properties in the courts of any
jurisdiction.

          (c)     The Borrower hereby irrevocably and unconditionally waives, to
the fullest extent it may legally and effectively do so, any objection which it
may now or hereafter have to the laying of venue of any suit, action or
proceeding arising out of or relating to this Agreement or any other Loan
Document in any court referred to in paragraph (b) of this Section. Each of the
parties hereto hereby irrevocably waives, to the fullest extent permitted by
law, the defense of an inconvenient forum to the maintenance of such action or
proceeding in any such court.

          (d)     Each party to this Agreement irrevocably consents to service
of process in the manner provided for notices in Section 9.01. Nothing in this
                                                 ------------
Agreement or any other Loan Document will affect the right of any party to this
Agreement to serve process in any other manner permitted by law.

          SECTION 9.10.  WAIVER OF JURY TRIAL. EACH PARTY HERETO HEREBY WAIVES,
                         --------------------
TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A
TRIAL BY JURY IN ANY LEGAL PROCEEDING DIRECTLY OR INDIRECTLY ARISING OUT OF OR
RELATING TO THIS AGREEMENT, ANY OTHER LOAN DOCUMENT OR THE TRANSACTIONS
CONTEMPLATED HEREBY (WHETHER BASED ON CONTRACT, TORT OR ANY OTHER THEORY). EACH
PARTY HERETO (A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY
OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD
NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER AND (B)
ACKNOWLEDGES THAT IT AND THE OTHER PARTIES HERETO HAVE BEEN INDUCED TO ENTER
INTO THIS AGREEMENT BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND
CERTIFICATIONS IN THIS SECTION.

          SECTION 9.11.  Headings. Article and Section headings and the Table of
                         --------
Contents used herein are for convenience of reference only, are not part of this
Agreement and shall not affect the construction of, or be taken into
consideration in interpreting, this Agreement.

          SECTION 9.12.  Confidentiality. Each of the Administrative Agent, the
                         ---------------
Issuing Bank and the Lenders agrees to maintain the confidentiality of the
Information (as defined below), except that Information may be disclosed:

          (a)     to its and its Affiliates' directors, officers, employees and
agents, including accountants, legal counsel and other advisors (it being
understood that the Persons to

                                       71
<PAGE>

whom such disclosure is made will be informed of the confidential nature of such
Information and instructed to keep such Information confidential),

          (b)     to the extent requested by any regulatory authority,

          (c)     to the extent required by applicable laws or regulations or by
any subpoena or similar legal process,

          (d)     to any other party to this Agreement,

          (e)     in connection with the exercise of any remedies hereunder or
any suit, action or proceeding relating to this Agreement or any other Loan
Document or the enforcement of rights hereunder or thereunder,

          (f)     subject to an agreement containing provisions substantially
the same as those of this Section, to any assignee of or Participant in, or any
prospective assignee of or Participant in, any of its rights or obligations
under this Agreement,

          (g)     with the consent of the Borrower or

          (h)     to the extent such Information (i) becomes publicly available
other than as a result of a breach of this Section or (ii) becomes available to
the Administrative Agent, the Issuing Bank or any Lender on a nonconfidential
basis from a source other than the Borrower.

For the purposes of this Section, "Information" means all information received
from the Borrower relating to the Borrower or its business, other than any such
information that is available to the Administrative Agent, the Issuing Bank or
any Lender on a nonconfidential basis prior to disclosure by the Borrower;
provided that, in the case of information received from the Borrower after the
Closing Date, such information is clearly identified at the time of delivery as
confidential.  Any Person required to maintain the confidentiality of
Information as provided in this Section shall be considered to have complied
with its obligation to do so if such Person has exercised the same degree of
care to maintain the confidentiality of such Information as such Person would
accord to its own confidential information.

          SECTION 9.13.  Interest Rate Limitation. Notwithstanding anything
                         ------------------------
herein to the contrary, if at any time the interest rate applicable to any Loan,
together with all fees, charges and other amounts which are treated as interest
on such Loan under applicable law (collectively the "Charges"), shall exceed the
maximum lawful rate (the "Maximum Rate") which may be contracted for, charged,
taken, received or reserved by the Lender holding such Loan in accordance with
applicable law, the rate of interest payable in respect of such Loan hereunder,
together with all Charges payable in respect thereof, shall be limited to the
Maximum Rate and, to the extent lawful, the interest and Charges that would have
been payable in respect of such Loan but were not payable as a result of the
operation of this Section shall be cumulated and the interest and Charges
payable to such Lender in respect of other Loans or periods shall be increased
(but not above the Maximum Rate therefor) until such cumulated amount, together
with interest thereon at the Federal Funds Effective Rate to the date of
repayment, shall have been received by such Lender.

                                       72
<PAGE>

          SECTION 9.14.  Nonliability of Documentation Agent. The Documentation
                         -----------------------------------
Agent shall not have any fiduciary responsibilities to the Borrower. The
Documentation Agent does not undertake any responsibility to the Borrower to
review or inform the Borrower of any matter in connection with any phase of the
Borrower's business or operations. The Borrower agrees that the Documentation
Agent shall not have any liability to the Borrower (whether sounding in tort,
contract, or otherwise) for losses suffered by the Borrower in connection with,
arising out of, or in any way related to, the transactions contemplated and the
relationship established by the Loan Documents, or any act, omission or event
occurring in connection therewith, unless it is determined in a final non-
appealable judgment by a court of competent jurisdiction that such losses
resulted from the gross negligence or willful misconduct of the Documentation
Agent or a breach of the Loan Documents by the Documentation Agent. Nothing in
this Section 9.14 shall affect the relationship between the Borrower and any
Lender.

                                       73
<PAGE>

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

                                      PPL MONTANA, LLC,
                                      as Borrower

                                             by   ______________________________
                                                  Name:
                                                  Title:

                                      [additional signature pages to follow]
<PAGE>

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

                                      THE CHASE MANHATTAN BANK,
                                      as Lender and as Administrative Agent

                                            by   _______________________________
                                                 Name:
                                                 Title:

                                      [additional signature pages to follow]
<PAGE>

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

                              JP MORGAN, A DIVISION OF CHASE SECURITIES INC.,
                              as Lead Arranger and Book Runner

                                    by   _________________________________
                                         Name:
                                         Title:

                              [additional signature pages to follow]

                                       76
<PAGE>

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

                              THE BANK OF NOVA SCOTIA,

                              as Lender and as Syndication Agent

                                    by   __________________________________
                                         Name:
                                         Title:

                              [additional signature pages to follow]

                                       77
<PAGE>

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

                              THE INDUSTRIAL BANK OF JAPAN, LIMITED,

                              as Lender and as Documentation Agent

                                    by   ___________________________________
                                         Name:
                                         Title:

                              [additional signature pages to follow]

                                       78
<PAGE>

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

                              CREDIT SUISSE FIRST BOSTON,
                              as Lender

                                    by   _____________________________________
                                         Name:
                                         Title:

                                    by   _____________________________________
                                         Name:
                                         Title:

                              [additional signature pages to follow]

                                       79
<PAGE>

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

                              PNC BANK, NATIONAL ASSOCIATION,
                              as Lender

                                    by   ____________________________________
                                         Name:
                                         Title:

                              [additional signature pages to follow]

                                       80
<PAGE>

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

                              KBC BANK, N.V.,
                              as Lender

                                    by   ____________________________________
                                         Name:
                                         Title:

                              [additional signature pages to follow]

                                       81
<PAGE>

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

                              UNION BANK OF CALIFORNIA, N.A.,
                              as Lender

                                    by   ____________________________________
                                         Name:
                                         Title:

                              [additional signature page to follow]

                                       82
<PAGE>

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

                              MELLON BANK, N.A.,
                              as Lender

                                    by   ____________________________________
                                         Name:
                                         Title:

                                       83<PAGE>

                                                                   EXHIBIT 10.34

PORTIONS OF THIS EXHIBIT WERE OMITTED AND FILED SEPARATELY WITH THE SECURITIES
AND EXCHANGE COMMISSION PURSUANT TO AN APPLICATION FOR CONFIDENTIAL TREATMENT
FILED WITH THE COMMISSION PURSUANT TO RULE 24b-2 UNDER THE SECURITIES EXCHANGE
ACT OF 1934.  SUCH PORTIONS ARE MARKED BY ASTERISKS.

                       COMMERCIAL MANUFACTURING AGREEMENT

THIS COMMERCIAL MANUFACTURING AGREEMENT (the "Agreement") is entered into on
this May 22, 2001 (the "Effective Date"), by and between ViroPharma Incorporated
("ViroPharma"), a Delaware corporation having a place of business at 405
Eagleview Boulevard, Exton, Pennsylvania 19341, and Produits Chimiques
Auxilliaires et de Synthese, SELOC France Division ("PCAS") having a place of
business at 23, rue Bossuet-Z.I. de la Vigne aux Loups, 91161 Lonjumeau, France.
ViroPharma and PCAS may each be referred to herein individually as a "Party" and
collectively as the "Parties".

WHEREAS, ViroPharma has developed a new pharmaceutical active ingredient,
pleconaril and would like to obtain commercial supplies of Pleconaril;

PCAS has worked for ViroPharma, under previous agreements, to develop the
manufacturing process of Pleconaril, and has already supplied ViroPharma with
initial commercial quantities of Pleconaril, and has the ability and desire to
go on supplying ViroPharma with commercial quantities of pleconaril; and

InterChem Corporation, ("InterChem"), a corporation having an address at 120,
Route 17 North, Paramus, NJ, 07653-1579, has been appointed by PCAS as its
distributor for Pleconaril and other products in the USA and Canada.

NOW THEREFORE, in consideration of the mutual promises and covenants set forth
below and other good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledged, the Parties agree as follows:

1.   DEFINITIONS.  The following terms shall, unless the context otherwise
     requires, have the respective meanings set out below, and grammatical
     variations of such terms shall have corresponding meanings:

     1.1  "AFFILIATE" means a corporation, partnership, entity, person, firm,
          company, or joint venture, whether de jure or de facto, that controls,
          is controlled by or is under the common control with the referenced
          Party.  For the purposes of this definition the word "control"
          (including, with correlative meaning, the terms "controlled by" or "is
          under the common control with") means (a) ownership directly or
          indirectly of at least fifty percent (50%) of the voting stock of the
          applicable entity, or such lesser percentage that is the maximum
          allowed to be owned by a foreign corporation in a particular
          jurisdiction, or (b) the actual ability to control the management and
          operations of the applicable entity.

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                 Page 1
<PAGE>

     1.2  "API" means Pleconaril manufactured at the Manufacturing Site in
          accordance with the Specifications.

     1.3  "API COMPONENTS" means Raw Material, Starting Material, and Packaging
          Material that comply with the Specifications and that are necessary
          for the manufacture and packaging of API pursuant to this Agreement.

     1.4  "CERTIFICATE OF ANALYSIS AND CONFORMANCE" means a certificate for a
          batch of bulk API in a form to be mutually agreed to by the Parties,
          as may be amended from time to time with the agreement of the Parties.

     1.5  "cGMP" means the current good manufacturing practices for drug
          substances as set forth in the U.S. Food, Drug, and Cosmetic Act and
          applicable regulations promulgated thereunder, as amended from time to
          time.

     1.6  "CONFIDENTIAL INFORMATION" means:

          1.6.1  all secret, confidential or proprietary information or data,
                 whether provided in written, oral, graphic, video, computer or
                 other form, provided by ViroPharma to PCAS pursuant to this
                 Agreement or any previous agreement between the Parties, or
                 generated by either Party pursuant to this Agreement or any
                 previous Agreement between the Parties, including, but not
                 limited to, ViroPharma Know-How, information relating to
                 ViroPharma's existing or proposed research, development
                 efforts, business, products, the terms of this Agreement and
                 any other materials that have not been made available by
                 ViroPharma to the general public. Failure to mark any of the
                 Confidential Information as confidential or proprietary shall
                 not affect its status as Confidential Information under the
                 terms of this Agreement.

          1.6.2  Notwithstanding the foregoing Section 1.6.1, Confidential
                 Information shall not include any information or materials
                 that: (i) at the time of disclosure by ViroPharma to PCAS is
                 in, or after disclosure by ViroPharma to PCAS becomes part of
                 the public domain, through no improper act on the part of PCAS
                 or on the part of any of its respective employees or
                 contractors; (ii) was in PCAS' possession at the time that such
                 information was first disclosed by ViroPharma, as shown by
                 written evidence, and was not acquired, directly or indirectly,
                 from ViroPharma; (iii) PCAS receives from a third party,
                 provided that such Information was not obtained by such third
                 party, directly or indirectly, from ViroPharma; or (iv) is
                 required to be disclosed by law, provided that ViroPharma is
                 given reasonable advance notice of such requirement to divulge
                 and an opportunity to obtain a protective order.

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                 Page 2
<PAGE>

          1.6.3  all secret, confidential or proprietary information or data,
                 whether provided in written, oral, graphic, video, computer or
                 other form, provided by PCAS to ViroPharma pursuant to this
                 Agreement or any previous agreement between the Parties, or
                 generated by either Party pursuant to this Agreement or any
                 previous Agreement between the Parties, including, but not
                 limited to, PCAS know-how, information relating to PCAS'
                 existing or proposed research, development efforts, business,
                 products, the terms of this Agreement and any other materials
                 that have not been made available by PCAS to the general
                 public. Failure to mark any of the Confidential Information as
                 confidential or proprietary shall not affect its status as
                 Confidential Information under the terms of this Agreement.

          1.6.4  Notwithstanding the foregoing Section 1.6.3, Confidential
                 Information shall not include any information or materials
                 that: (i) at the time of disclosure by PCAS to ViroPharma is
                 in, or after disclosure by PCAS to ViroPharma becomes part of
                 the public domain, through no improper act on the part of
                 ViroPharma or on the part of any of its respective employees or
                 contractors; (ii) was in ViroPharma's possession at the time
                 that such information was first disclosed by PCAS, as shown by
                 written evidence, and was not acquired, directly or indirectly,
                 from PCAS; (iii) ViroPharma receives from a third party,
                 provided that such Information was not obtained by such third
                 party, directly or indirectly, from PCAS; or (iv) is required
                 to be disclosed by law, provided that PCAS is given reasonable
                 advance notice of such requirement to divulge and an
                 opportunity to obtain a protective order.

     1.7  "(Euro)/$ EXCHANGE RATE" means the Euro per U.S. dollar exchange rate
          as published in The Wall Street Journal on the specified date, or if
          no rate is reported on that date, on the next subsequent date on which
          the rate is reported.

     1.8  "FDA" means the United States Food and Drug Administration.

     1.9  "INVENTION" means any invention, modification, discovery, improvement,
          technology, trade secret, chemical or biological material, assay,
          method, process, technique, documentation, scientific and technical
          data, drawing or other information, whether patentable or not,
          resulting from the use of the Specifications, any process information,
          any Confidential Information of ViroPharma, or resulting from the
          manufacture of API or Starting Material.

     1.10 "MANUFACTURING SITE" means PCAS' sites at 19, route de Meulan, F-
          78520, Limay, France; route de Lassay, F-61410, Couterne, France; rue
          des Freres Lumiere, F-38300, Bourgoin-Jallieu France; and any other
          site approved by ViroPharma in accordance with Section 3.7.1.

     1.11 "PACKAGING MATERIAL" means any materials needed to contain, store,
          package and/or ship API.

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                 Page 3
<PAGE>

     1.12 "PLECONARIL" means the compound pleconaril with CAS No. 153168-05-9,
          also known as VP 63843.

     1.13 "RAW MATERIAL" means chemicals, ingredients, and other supplies
          necessary for the manufacture of API, other than the Starting
          Materials, that meet reasonable industry standards and the
          Specifications.

     1.14 "REGULATORY AUTHORITY" means any national (e.g., the United States
          Food and Drug Administration), supra-national (e.g., the European
          Commission, the Council of the European Union, or the European Agency
          for the Evaluation of Medicinal Products), regional, state or local
          regulatory agency, department, bureau, commission, council or other
          governmental entity in each country of the world involved in the
          granting of regulatory approval for the marketing of Pleconaril.

     1.15 "SAMPLE" means 100 g of a substance, unless otherwise stated in the
          Specifications.

     1.16 "SPECIFICATIONS" means:  (a) the product, formula, processing,
          testing, storage, packaging, handling, and shipping specifications,
          including, without limitation, the master batch record, that will be
          supplied by ViroPharma to PCAS; (b) the quality assurance and quality
          control specifications and analytical methods that will be supplied by
          ViroPharma to PCAS; and (c) the requirements of cGMP, in each case as
          may be amended to meet the requests or requirements of FDA or another
          Regulatory Authority.  The complete and comprehensive Specifications
          to be supplied by ViroPharma to PCAS under Sections 1.16(a-b) shall be
          substantially similar to the summary specifications set forth in
          Exhibit 1.16(a-b) attached to and included in this Agreement.

     1.17 "STARTING MATERIALS" means:  ***********, also known as *********,
          and *********** also known as *********, that meet the Specifications.

     1.18 "VALIDATION BATCH" means a batch of approximately 580 kg of API, but
          in no event less than 450 kg of API, produced pursuant to Section 3.8
          and the Validation Protocol.

     1.19 "VALIDATION CAMPAIGN" means three Validation Batches made
          consecutively, with no failed attempts to make a Validation Batch
          intervening.

     1.20 "VALIDATION PROTOCOL" means the protocol for the production of the
          Validation Campaign of API, set forth in Exhibit 1.20 attached to and
          included in this Agreement, as may be amended from time to time by
          written agreement of the Parties.

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     1.21 "VALIDATION REPORT" means the report and related documentation
          described in the Validation Protocol, regarding the manufacture and
          testing of all Validation Batches and the Validation Campaign.

     1.22 "VIROPHARMA KNOW-HOW" means all inventions, technology, trade
          secrets, physical, chemical or biological material, assays, methods,
          documentation, scientific and technical data and other information
          (excluding ViroPharma Patents) that ViroPharma owns or otherwise has a
          right to use as of the date of this Agreement or at any time during
          the term of this Agreement.

     1.23 "VIROPHARMA PATENTS" means all United States and foreign patents and
          patent applications, including divisions, continuations,
          continuations-in-part, additions, renewals, extensions, re-
          examinations and reissues of all such patents and patent applications,
          that are owned or licensed by ViroPharma.

2.  TERM

The term of this Agreement will begin on the Effective Date, and unless earlier
terminated as provided in Article 13, shall continue in effect until
December 31, 2003.

3.  API MANUFACTURE AND SUPPLY

     3.1  Manufacture.  PCAS shall manufacture API at the Manufacturing Site in
          accordance with the Specifications, including, without limitation
          cGMP, and with its representations, warranties and covenants under
          this Agreement, for delivery to ViroPharma in accordance with
          Section 4.5.

     3.2  REQUIREMENTS AND MINIMUM SUPPLY.

          3.2.1  PCAS agrees to supply up to ********** kg of API in calendar
                 year 2001, up to ********* kg of API in calendar year 2002, and
                 up to ********* kg of API in calendar year 2003 and subsequent
                 calendar years, if any, of the Agreement. In the event that
                 ViroPharma requires more than these amounts from PCAS, PCAS
                 shall use its best efforts to supply such increased
                 requirements.

          3.2.2  ViroPharma commits to purchasing from PCAS at minimum:

                 a.  in calendar year 2001  ********* kg of API;

                 b.  in calendar year 2002, the lesser of (i) ********* kg of
                     API, or (ii) *****% of its requirements for API in such
                     year; and

                 c.  in calendar year 2003, the lesser of (i) ********* kg of
                     API, or (ii) *****% of its requirements for API.

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                 Nothing in this Section 3.2.2 shall prevent ViroPharma from
                 purchasing more than these amounts from PCAS.

          3.2.3  If PCAS is unable to fulfill its commitments under
                 Section 3.2.1, or ViroPharma has fulfilled its commitments
                 under Section 3.2.2, nothing in this Agreement shall prevent
                 ViroPharma from purchasing Pleconaril from a third party.

          3.2.4  Nothing in this Agreement shall preclude ViroPharma from taking
                 whatever steps necessary to qualify alternative suppliers of
                 Pleconaril, including, but not limited to selling any batches
                 of Pleconaril reasonably required to be manufactured for
                 purposes of the qualification of such alternative suppliers,
                 and for maintaining such qualifications, e.g., validation
                 batches.

          3.2.5  If ViroPharma exercises its right to have quantities of API
                 manufactured by one or more alternative suppliers, and if such
                 alternative suppliers require ViroPharma to supply Starting
                 Materials, then PCAS shall have a right of first offer to
                 produce a minimum of *****% of ViroPharma's requirements of
                 such Starting Materials, provided that PCAS is able to supply
                 the said quantities at a competitive price.

     3.3  THIRD PARTIES.  PCAS shall not manufacture Pleconaril for or sell
          Pleconaril to any third parties during the term of this Agreement
          without the prior written consent of ViroPharma.

     3.4  DOCUMENTATION.  PCAS will prepare a Certificate of Analysis and
          Conformance for each batch of API confirming that such batch conforms
          with the Specifications.  With its shipment of such batch pursuant to
          Section 4.5 and Article 5 below, PCAS shall include the Certificate of
          Analysis and Conformance, identifying to which batch the certificate
          relates, and, at the request of ViroPharma, or as required in the
          Specifications or the Certificate of Analysis and Conformance, any raw
          data or executed batch records regarding the manufacture of the batch
          that ViroPharma reasonably requests.

     3.5  SAMPLE RETENTION.  PCAS shall retain Samples of the Starting Material,
          each Raw Material identified for sample retention in the
          Specifications, and the manufactured API, identifying them by batch of
          manufactured API.   PCAS shall retain such Samples under normal
          warehouse conditions for the longer of:  two years after the delivery
          of the relevant batch of API to ViroPharma, or the period required by
          law.  PCAS shall promptly deliver such samples to ViroPharma upon
          ViroPharma's request.  PCAS will contact ViroPharma at least sixty
          days before the planned destruction of any such Samples, at which time
          ViroPharma may request that PCAS deliver such Samples to ViroPharma at
          ViroPharma's cost.  PCAS shall promptly notify ViroPharma in writing
          of any accidental loss or destruction of such Samples.

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     3.6  API COMPONENT SUPPLY.  PCAS shall be solely responsible for obtaining
          or manufacturing at its own costs sufficient inventories of API
          Components to complete the manufacture and delivery of the batches of
          API ordered pursuant to the Agreement.  The foregoing sentence shall
          not preclude ViroPharma from assisting in obtaining supply of API
          Components on behalf of PCAS if PCAS and ViroPharma so agree.  PCAS
          shall be solely responsible for inspecting the API Components to
          ensure that they comply with the Specifications and PCAS is solely
          responsible for the return or other disposal of API Components that do
          not meet the Specifications.  PCAS shall supply, at ViroPharma's
          request, written reports and analyses of API Components to demonstrate
          conformance to applicable Specifications.

     3.7  CHANGES.

          3.7.1  PRIOR APPROVAL AND NOTICE. PCAS shall not change the
                 Manufacturing Site, the Specifications, the API Components, or
                 any material aspect of the manufacture of API without the prior
                 written consent of ViroPharma, regardless of whether any such
                 change requires FDA or other Regulatory Authority approval.
                 PCAS shall provide ViroPharma with all reasonably requested
                 data, documentation and assistance to effectuate such change.
                 PCAS shall provide ViroPharma with thirty (30) days written
                 notice before any planned move of the manufacturing of Starting
                 Materials or API between PCAS' Bourgoin-Jallieu, Couterne, and
                 Limay sites, and may proceed with such move if ViroPharma does
                 not object to such written notice within fifteen (15) days.
                 PCAS may sub-contract the manufacturing of Starting Materials
                 after providing notification to and receiving written approval
                 from ViroPharma.

          3.7.2  CHANGES REQUIRED BY REGULATORS. If FDA or another Regulatory
                 Authority requires ViroPharma to change the Manufacturing Site,
                 the Specifications, or the API Components for manufacturing
                 API, PCAS shall make such changes. If changes in manufacturing
                 made pursuant this Section 3.7.2 change the costs of
                 manufacturing API by more than 10%, then the Parties shall
                 negotiate in good faith to share the costs between them.

          3.7.3  PERMISSIVE CHANGES.

                 a.  PCAS may propose changes to the Manufacturing Site, the
                     Specifications, or the API Components for manufacturing API
                     by providing ViroPharma with a detailed written report
                     describing such proposed changes, for ViroPharma's review
                     and approval. Except as set forth in Section 6.5, PCAS
                     shall bear the costs of such changes.

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                 b.  If ViroPharma requests a change in the Manufacturing Site,
                     the Specifications, or the API Components for manufacturing
                     API that is not the result of a requirement of FDA or
                     another Regulatory Authority, PCAS shall use its best
                     efforts to accommodate such request, and ViroPharma will
                     reimburse PCAS for the costs of such changes.

          3.7.4  COMPLIANCE WITH STANDARDS. In the event that PCAS's activities
                 are not performed at the previously approved Manufacturing
                 Site, or in accordance with the previously approved
                 Specifications, PCAS's efforts to bring its activities into
                 compliance with such requirements shall not constitute a change
                 under this Section 3.7.

     3.8  VALIDATION BATCHES AND VALIDATION CAMPAIGNS.

          3.8.1  REQUIREMENTS BEFORE MANUFACTURE OF VALIDATION BATCHES.  PCAS
                 shall not begin manufacturing any Validation Batch until both:

                 (a)  PCAS has received the complete and comprehensive
                      Specifications from ViroPharma pursuant to Section 1.16,
                      and

                 (b)  the Parties have agreed to the form of a Certificate of
                      Analysis and Conformance.

          3.8.2  MANUFACTURE. PCAS shall manufacture a Validation Campaign of
                 API consistent with the Validation Protocol, each Validation
                 Batch of which will be ordered and shipped like a standard
                 batch, except as set forth in the Validation Protocol. PCAS
                 shall deliver to ViroPharma a draft Validation Report within
                 twenty-one (21) days after the shipment of the final Validation
                 Batch in a Validation Campaign. ViroPharma will provide PCAS
                 with comments on the draft Validation Report within fifteen
                 (15) days of receiving such draft. PCAS shall provide
                 ViroPharma with a final Validation Report within fifteen (15)
                 days after receiving ViroPharma's comments on the draft report.
                 PCAS shall make all reasonable changes to the Validation Report
                 requested by ViroPharma. If requested by ViroPharma, PCAS will
                 provide a copy of the final Validation Report in electronic
                 format.

     3.9  TECHNOLOGY TRANSFER.  At ViroPharma's request, PCAS shall assist
          ViroPharma in transferring to third parties manufacturing Pleconaril
          for ViroPharma all technology and know-how necessary to manufacture
          Pleconaril to the Specifications and in compliance with all applicable
          laws and regulations.  Such transfer shall be for consulting fees of
          $1000 per person per day and reasonable  travel and out-of-pocket
          expenses.

4.  ORDERING AND SHIPMENT

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     4.1  FORECASTS.  On or before the fifteenth day of each calendar quarter
          starting respectively in January, April, July, and October, ViroPharma
          shall update the eighteen-month quarterly forecast of API needs set
          forth in Exhibit 4.1 attached to and included in this Agreement,
          beginning with the next calendar quarter.  Notwithstanding the
          foregoing, ViroPharma shall promptly update such forecast if its
          anticipated requirements for the first three months of such forecast
          have changed by more than twenty percent.

     4.2  MINIMUM BATCH SIZE.  Orders for API shall be in multiples of whole
          batches.

     4.3  FIRM ORDERS.  On or before the fifteenth day of each month, ViroPharma
          shall provide PCAS with a firm written order (a "Firm Order") for the
          amount of API to be produced and delivered to ViroPharma by the end of
          the ******* month following the month in which such Firm Order is
          made, unless ViroPharma specifies a different later date for delivery.
          The Firm Order shall include a purchase order number and specify the
          amount of API to be manufactured and the location of delivery.  The
          amount of API ordered by ViroPharma in a Firm Order shall be binding
          on ViroPharma and PCAS, and shall not be subject to reduction.  PCAS
          shall have the right to reject any Firm Offer for an amount in excess
          of the amount of its annual agreed supply set forth in Section 3.2.1.
          within fifteen (15) days of the receipt of such Firm Order.

     4.4  TIME OF THE ESSENCE.

          4.4.1  GENERAL. PCAS understands that time is of the essence to the
                 manufacture and delivery of API under this Agreement. If at any
                 time PCAS reasonably believes that it will be unable to satisfy
                 a Firm Order that was not properly rejected in accordance with
                 Section 4.3, in either amount or delivery time, it shall notify
                 ViroPharma immediately, except that PCAS may use the Safety
                 Stock to avoid any such shortfall or delay. After discussion
                 with PCAS about how to remedy any such problem, ViroPharma may
                 accept that amount of such Firm Order that PCAS is able to
                 deliver. If ViroPharma elects to accept a reduced delivery,
                 then, in accordance with Section 6.2, the charge for such
                 amount of API shall be based on the amount ordered, and not the
                 amount delivered.

          4.4.2  COST. If ViroPharma accepts a reduced Firm Order after notice
                 from PCAS pursuant to Section 4.4.1, ***********************
                 incurred by ViroPharma in obtaining an equivalent amount of
                 Pleconaril from a third party in excess of what PCAS would have
                 charged for such quantity of Pleconaril (the "Excess"),
                 provided that ViroPharma reasonably believes that such third
                 party can deliver the replacement Pleconaril to ViroPharma
                 before PCAS would have delivered the delayed order, and except
                 to the extent that such Firm Order would have exceeded PCAS'
                 supply obligations under Sections 3.2.1 or 4.5.1., as follows:

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                 (a)  if the Excess is ****% or less of the amount that PCAS
                      would have charged for the relevant quantity of
                      Pleconaril, PCAS shall pay all of the Excess;

                 (b)  if the Excess is more than ****%, but less than or equal
                      to *****% of the amount that PCAS would have charged for
                      the relevant quantity of Pleconaril, then PCAS shall pay a
                      portion of the Excess equal to *****% of the amount that
                      PCAS would have charged for the relevant quantity of
                      Pleconaril, and the Parties shall split equally the
                      remainder of the Excess; and

                 (c)  if the Excess is more than ****% of the amount that PCAS
                      would have charged for the relevant quantity of
                      Pleconaril, then PCAS shall pay a portion of the Excess
                      equal to *****% of the amount that PCAS would have charged
                      for the relevant quantity of Pleconaril, and ViroPharma
                      shall pay the remainder of the Excess.

     4.5  SHIPMENT.  PCAS shall deliver all API to ViroPharma "DDP, Exton,
          Pennsylvania," or such other place within the USA as ViroPharma may
          designate in its Firm Order, as the term DDP is defined in INCO Terms
          1990, Pub. No. 460.  Transport conditions shall comply with all
          applicable laws and regulations, and with the Specifications.  PCAS
          shall notify ViroPharma immediately of any loss of or damage to API in
          transit.  If any shipment of API is lost or damaged, the Parties will
          cooperate in attempting to locate such shipment, or to obtain
          insurance reimbursement for such shipment, and to arrange a production
          schedule for PCAS to replace the lost or damaged API.  If Pleconaril
          is removed from the Pharmaceutical Appendix and results in a new duty
          rate classification, the prevailing price to ViroPharma will be
          adjusted to fully compensate PCAS for this cost.

     4.6  SAFETY STOCK.  During 2002 PCAS shall build up a commercially
          reasonable safety stock of API.  PCAS shall refresh such safety stock
          regularly on a "first-in-first-out" basis from batches of API
          manufactured during the course of this Agreement.

5.  ACCEPTANCE

     5.1  RIGHT OF REJECTION.  Without limiting ViroPharma's other rights and
          remedies under this Agreement or in law or equity, ViroPharma shall
          have the right to reject any API that fails to meet the
          Specifications, or that otherwise fails to comply with PCAS' warranty
          under Section 11.2 of this Agreement ("Non-Conforming API").

     5.2  PROCEDURES FOR REJECTION.

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          5.2.1  Within thirty (30) days of receipt of any API, ViroPharma or
                 its designee shall inspect such API and give PCAS written
                 notice of: (i) any Non-Conforming API, or (ii) any shortages in
                 the amount of API delivered (together, a "Deficiency Notice").
                 The Deficiency Notice shall identify the rejected API by lot
                 number and describe the basis for rejection.

          5.2.2  Within fifteen days of receiving a Deficiency Notice, PCAS
                 shall notify ViroPharma in writing as to whether it agrees with
                 the rejection. If ViroPharma and PCAS fail to agree on the
                 validity of such rejection within ten days after PCAS' notice,
                 the Parties shall agree on an independent laboratory or
                 consultant (the "Lab"), whose decision shall be binding, to
                 test the rejected API. If such testing reveals that the API in
                 fact was Non-Conforming API, PCAS shall pay the costs, fees and
                 expenses that the Lab incurred in testing the API in question.
                 If such testing reveals that the API in fact was not Non-
                 Conforming Product, ViroPharma shall pay the costs, fees and
                 expenses that the Lab incurred in testing the API in question.

     5.3  RESPONSIBILITY FOR NON-CONFORMING API AND SHORTAGES.

          5.3.1  PCAS shall be responsible for replacing at its sole cost any
                 Non-Conforming API properly rejected in accordance with Section
                 5.2 within a reasonable time not to exceed sixty (60) days from
                 the date that the Parties agree that the API is Non-Conforming,
                 or that a Lab confirms that the API is Non-Conforming.

          5.3.2  In the event of any shortage of API in excess of ****% of the
                 total amount ordered, where each batch is expected to contain
                 **** kg, at ViroPharma's sole discretion, either:

                 (a)  PCAS shall at its sole expense prepare sufficient
                      additional API to remedy the shortage, or

                 (b)  The amount due for the full amount of API requested shall
                      be prorated to reflect the shortfall, and this reduced
                      amount shall be full payment for the amount of API
                      actually delivered. For purposes of Sections 3.2.2 and
                      6.2, ViroPharma shall be deemed to have ordered and
                      purchased the full amount ordered.

     5.4  DISPOSAL OF NON-CONFORMING PRODUCT.  At PCAS' request, direction, and
          sole cost, ViroPharma shall either return to PCAS, or destroy any Non-
          Conforming API.  PCAS shall reimburse ViroPharma within thirty days of
          receiving any invoice for the costs of destroying or returning any
          Non-Conforming API.

     5.5  INVESTIGATION.  PCAS will cooperate with ViroPharma at PCAS's cost in
          investigating the cause of any production of Non-Conforming API.

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6.  PRICE AND PAYMENT.

     6.1  GENERAL TERMS.

          6.1.1  INVOICES AND PAYMENTS. PCAS shall include an invoice with each
                 batch of API delivered to ViroPharma. All invoices that are not
                 reasonably disputed by ViroPharma in accordance with Article 5
                 or otherwise shall be payable within forty-five (45) days after
                 ViroPharma's receipt. The fees and charges due hereunder shall
                 be payable in U.S. dollars. All payments due from ViroPharma
                 hereunder shall be paid to PCAS by a bank transfer sent to
                 PCAS's bank or by a check payable to the Designee on behalf of
                 PCAS. Notwithstanding the foregoing, PCAS may designate
                 InterChem, or another third party, in writing (the "Designee")
                 to assist PCAS in shipping API to ViroPharma. In such case, all
                 sums due hereunder from ViroPharma shall be paid to Designee on
                 behalf of PCAS, and upon such payment, ViroPharma shall have no
                 further obligation in respect of such payment to PCAS. The use
                 of Designee by PCAS and the receipt by ViroPharma of any API
                 delivered to it by Designee, shall in no way diminish any
                 rights that ViroPharma may have against PCAS, and shall not act
                 as a waiver or estoppel of any claim that ViroPharma may have
                 at any time against PCAS arising from or relating to this
                 Agreement. The Parties acknowledge that the use of Designee is
                 for the convenience of PCAS.

          6.1.2  INVOICE RATE AND CORRECTIONS. The amount invoiced for any batch
                 of API delivered to ViroPharma shall be at the per kilo rate
                 set forth in Section 6.2 for the full amount of API projected
                 to be ordered in the calendar year in which the order is made.
                 If at the end of a calendar year, because of the amount of API
                 ordered in such calendar year ViroPharma was entitled to a
                 lower rate per kilo than was actually invoiced, PCAS shall
                 refund ViroPharma the difference within sixty days of the end
                 of such calendar year. If at the end of a calendar year PCAS
                 was entitled to a higher rate per kilo than was actually
                 invoiced, PCAS may invoice ViroPharma for the difference, which
                 invoice shall be payable in accordance with Section 6.1.1
                 above.

          6.1.3  DEDUCTION FOR PRIOR PAYMENTS FOR STARTING MATERIALS. ViroPharma
                 shall be credited for any amounts paid under the agreement
                 between ViroPharma and PCAS dated February 8, 2001, for
                 "Materials" as that term is defined in such agreement. Any
                 invoices under Section 6.1 shall be offset by the amount of
                 such credit until the full amount of the credit has been
                 reached.

     6.2  PRICE FOR API.   Pricing for API delivered shall be based on the total
          amount of API ordered by ViroPharma in a calendar year as follows. If
          the amount of API

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          delivered is lower than the amount of API ordered, ViroPharma
          shall be charged for each kg delivered at the rate for the total
          amount ordered:

          6.2.1  CALENDAR YEAR 2001.  In calendar year 2001:

                 a.  If the total amount of API ordered by ViroPharma is less
                     than ****** kg, then ViroPharma shall pay $****** for each
                     kg;

                 b.  If the total amount of API ordered by ViroPharma is ******
                     kg or more, but less than ****** kg, then ViroPharma shall
                     pay $****** for each kg;

                 c.  If the total amount of API ordered by ViroPharma is ******
                     kg or more, but less than or equal to ****** kg, then
                     ViroPharma shall pay $****** for each kg; and

                 Notwithstanding the foregoing, if PCAS is unable to manufacture
                 any amount of API ordered by ViroPharma in calendar year 2001
                 up to ****** kg in accordance with Article 4, then such amount
                 of API shall be manufactured and delivered as soon as possible,
                 and shall be priced as if the order were placed in calendar
                 year 2002, in accordance with Section 6.2.2, below.

          6.2.2  CALENDAR YEAR 2002.  In calendar years 2002 and 2003:

                 a.  If the total amount of API ordered by ViroPharma is less
                     than ****** kg, then ViroPharma shall pay $****** for each
                     kg;

                 b.  If the total amount of API ordered by ViroPharma is
                     ****** kg or more, but less than ****** kg, then ViroPharma
                     shall pay $****** for each kg;

                 c.  If the total amount of API ordered by ViroPharma is
                     ****** kg or more, but less than ****** kg, then ViroPharma
                     shall pay $****** for each kg;

                 d.  If the total amount of API ordered by ViroPharma is
                     ****** kg or more, but less than ****** kg, then ViroPharma
                     shall pay $****** for each kg;

                 e.  If the total amount of API ordered by ViroPharma is
                     ****** kg or more, but less than ****** kg, then ViroPharma
                     shall pay $****** for each kg; and

                 f.  If the total amount of API ordered by ViroPharma is ******
                     kg or more, then ViroPharma shall pay $****** for each kg.

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     6.3  CHARGE FOR VALIDATION CAMPAIGN.

          6.3.1  Notwithstanding anything to the contrary in Section 6.2.1
                 above, ViroPharma shall pay PCAS $****** for each kg of API
                 delivered by PCAS to ViroPharma as part of a Validation
                 Campaign. Each such kg of API manufactured as part of a
                 Validation Campaign shall be included in the amounts ordered in
                 that calendar year for purposes of determining the price per kg
                 for the rest of the orders made in that calendar year.

          6.3.2  ViroPharma shall pay PCAS $********* for the Validation Report.

     6.4  EXCHANGE RATES.  The exchange rate to be used for Orders shall be as
          of the date of the Order, and shall be midway between 1.189 and the
          (Euro)/$ Exchange Rate on the Effective Date as set forth on Exhibit
          6.4 attached to and included in this Agreement, except that if the
          exchange rate on such date differs from the average of 1.189 and the
          (Euro)/$ Exchange Rate on the Effective Date by less than +/- 10% in
          calendar year 2001, and +/- 7% in subsequent calendar years, there
          will be no price adjustment. If the variance is greater than these
          amounts, the price adjustment will be equal to 50% of the total
          variance, or, stated algebraically, the amount in dollars charged for
          the API in accordance with Section 6.2, shall be multiplied by the
          following factor:

                         1 + (((1.189 + X) / 2)-Y) x 0.5
                              --------------------
                               (1.189 + X)/2

          where X is the (Euro)/$ Exchange Rate on the Effective Date and Y is
          the (Euro)/$ Exchange Rate on the date of the Order for API.

     6.5  SHARING OF EFFICIENCIES.  If pursuant to Section 3.7.3, the parties
          agree to implement any change for the purpose of obtaining cost
          reductions for manufacturing API, the parties shall share equally in
          the cost of such implementation, other than the cost of any regulatory
          filings, and in the cost reduction effected by such change.

7.  AUDITS.

Upon reasonable advance notice, ViroPharma, Sanofi-Synthelabo, or the authorized
representative of either company shall have the right at all reasonable times to
enter the facilities of PCAS to inspect all activities performed pursuant to
this Agreement and related documents and materials, including, without
limitation, the manufacturing facilities and warehouses of PCAS, API Components,
API, batch records, and SOPs.  PCAS shall make all documents and records
available for review and copying.  PCAS shall adopt reasonable suggestions of
ViroPharma or its authorized representative to correct any deficiencies
identified in any site visit or audit.  Provided that no significant adverse
findings are made during any audit in a calendar year, and there are no
indications of non-compliance with PCAS' representations and warranties

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in Section 11.2, including, without limitation, any adverse findings during an
inspection by FDA or any other Regulatory Authority, the maximum audit days per
year shall be five (5) with not more than three (3) representatives at a time.

8.  REGULATORY COMPLIANCE.

     8.1  General.  PCAS shall perform all activities under this Agreement in
          compliance with all applicable laws and regulations, and with any
          applicable professional standards.

     8.2  RECORDKEEPING.  PCAS shall maintain all records required by all
          applicable laws and regulations, and by any applicable professional
          standards.  Without in any way limiting the foregoing, PCAS shall keep
          records of the manufacturing, testing and shipping of API adequate to
          assist in resolving product complaints, conducting failure
          investigations, and performing recalls, field alerts, product
          withdrawals, field corrections or other similar actions.

     8.3  PERMITS AND AUTHORIZATIONS.  PCAS shall obtain and maintain all
          necessary manufacturing licenses and approvals for the manufacturing
          facilities required to perform the activities under this Agreement.

     8.4  INQUIRIES FROM REGULATORY AUTHORITIES.  PCAS shall promptly notify
          ViroPharma in writing if FDA or any foreign equivalent makes inquiries
          to PCAS regarding its activities under this Agreement.

     8.5  INSPECTIONS BY REGULATORY AUTHORITIES.  PCAS shall promptly notify
          ViroPharma if FDA or any foreign equivalent inspects PCAS regarding
          activities under this Agreement.  PCAS shall provide ViroPharma with a
          written report of any such inspection, noting with specificity any
          record or document reviewed by the regulatory inspector.  When a copy
          of a document or record is supplied to the inspector on request, that
          fact will be noted in the report.  PCAS shall keep copies of each of
          these records or documents in a separate inspection file and, on
          ViroPharma's request, will provide ViroPharma with copies of any or
          all of these records or documents.

     8.6  COMMUNICATIONS WITH REGULATORY AUTHORITIES.  PCAS shall promptly
          provide ViroPharma with a copy of all correspondence between PCAS and
          FDA or any foreign equivalent regarding activities under this
          Agreement, including, without limitation, any Form 483s, or similar
          notices or observations.  PCAS shall provide ViroPharma with a copy of
          any proposed response or correspondence to such regulatory authority
          that relates directly to activities under this Agreement for
          ViroPharma's approval at least five business days before the
          submission of such response or correspondence.

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<PAGE>

     8.7  NOTICE OF ACCIDENTS.  PCAS shall promptly notify ViroPharma of all
          accidents related to the manufacture of API, including, without
          limitation, those involving injury to persons, damage to property, or
          environmental release of chemicals.

     8.8. RECALLS.  PCAS shall immediately notify ViroPharma of any information
          in its possession relating to any batches of API that may require a
          recall, field alert, product withdrawal, field correction or other
          similar action whether based on design defect, manufacturing defect or
          otherwise.  The decision to initiate a recall, field alert, product
          withdrawal, field correction or other similar action, if any, shall be
          made and implemented by ViroPharma.  PCAS shall cooperate as
          reasonably necessary in planning and implementing any such action.
          PCAS shall bear the costs of any such action resulting from or arising
          out of any of the causes set forth in Section 12.1.1(a-c) up to
          (Euro) 45 million.

9.   OWNERSHIP OF INVENTIONS.

Any and all Inventions by PCAS shall be the sole and exclusive property of
ViroPharma.  PCAS hereby irrevocable assigns and transfers to ViroPharma, and to
the extent that an executory assignment is not enforceable, PCAS hereby agrees
to assign and transfer to ViroPharma, in writing, from time to time, upon
request, any and all right, title and interest that PCAS may have or may later
acquire in the Inventions under copyright, patent, and trade secret law in
perpetuity or for the longest period otherwise permitted by law, without the
necessity of further consideration.  Within thirty (30) calendar days of making
any Invention, PCAS shall notify ViroPharma, in writing, of the event and shall
assist ViroPharma in protecting ViroPharma's proprietary rights to said
Invention.  ViroPharma shall grant a royalty-free license to PCAS for use of
such Invention; provided, however, that without the prior written approval of
ViroPharma, PCAS shall not use such Invention in connection with a product
intended to treat or prevent the effect of viral infections in man.

10.  CONFIDENTIALITY.

     10.1  During the term of this Agreement and for a period of five years
           thereafter, PCAS shall maintain in confidence and shall use only for
           purposes of this Agreement all Confidential Information disclosed by
           ViroPharma under the Agreement, except as may be otherwise provided
           herein. Notwithstanding the foregoing, PCAS may disclose ViroPharma's
           Confidential Information to those of its directors, officers,
           employees, agents and consultants that have a need to know such
           Confidential Information in order to achieve the purposes of this
           Agreement (a "Recipient"), provided that such Recipient is bound by
           an obligation to hold in confidence and not make use of such
           Confidential Information for any purpose other than those permitted
           by this Agreement. PCAS will promptly notify ViroPharma upon
           discovery of any unauthorized use or disclosure of the Confidential
           Information. Any breach of this obligation of confidentiality by a
           Recipient or any other director, officer, employee, agent or
           consultant of PCAS shall be deemed a breech by PCAS. PCAS agrees that
           ViroPharma shall remain the owner of the

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                Page 16
<PAGE>

           Confidential Information, and all patent, copyright, trade secret,
           trademark and other intellectual property rights therein.

     10.2  During the term of this Agreement and for a period of five years
           thereafter, ViroPharma shall maintain in confidence and shall use
           only for purposes of this Agreement all Confidential Information
           disclosed by PCAS under the Agreement, except as may be otherwise
           provided herein. Notwithstanding the foregoing, ViroPharma may
           disclose PCAS' Confidential Information to those of its directors,
           officers, employees, agents and consultants that have a need to know
           such Confidential Information in order to achieve the purposes of
           this Agreement (a "Recipient"), provided that such Recipient is bound
           by an obligation to hold in confidence and not make use of such
           Confidential Information for any purpose other than those permitted
           by this Agreement. ViroPharma will promptly notify PCAS upon
           discovery of any unauthorized use or disclosure of the Confidential
           Information. Any breach of this obligation of confidentiality by a
           Recipient or any other director, officer, employee, agent or
           consultant of ViroPharma shall be deemed a breech by ViroPharma.
           ViroPharma agrees that PCAS shall remain the owner of the
           Confidential Information, and all patent, copyright, trade secret,
           trademark and other intellectual property rights therein.
           Notwithstanding the foregoing, this Section 10.2, shall not prevent
           or restrict ViroPharma in any way from using or disclosing ViroPharma
           Confidential information, from exercising its rights in and to the
           Inventions, or from performing any activity contemplated under this
           Agreement, including, without limitation: complying with applicable
           laws and regulations; submitting filings to Regulatory Authorities;
           responding to requests or questions from Regulatory Authorities;
           protecting or expanding its intellectual property rights; marketing
           or selling Pleconaril; and discussing, negotiating, or entering into
           collaborative agreements regarding Pleconaril.

11.  REPRESENTATIONS AND WARRANTIES.

     11.1  Representations and Warranties of the Parties.  Each of ViroPharma
           and PCAS represents, warrants and covenants to the other Party that:

           11.1.1  It is duly organized and validly existing and in good
                   standing under the laws of its organization or formation, and
                   has full corporate power and authority to enter into this
                   Agreement and to carry out the provisions hereof.

           11.1.2  It is duly authorized to execute and deliver this Agreement
                   and to perform its obligations hereunder.

           11.1.3  This Agreement is a legal and valid obligation binding upon
                   it and enforceable in accordance with its terms, except to
                   the extent limited by applicable bankruptcy and creditor's
                   rights laws. The execution, delivery and performance of this
                   Agreement by it does not conflict with any agreement,
                   instrument or understanding, oral or written, to which it is

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                Page 17
<PAGE>

                   a party or by which it may be bound, nor violate any material
                   law or regulation of any court, governmental body or
                   administrative or other agency having jurisdiction over it.

           11.1.4  It has obtained all necessary consents, approvals and
                   authorizations of all governmental authorities and other
                   entities and persons required to be obtained by it in
                   connection with entry into this Agreement.

           11.1.5  No agreement between it and a third party in existence as of
                   the Effective Date would prevent it from performing its
                   obligations under this Agreement or granting to the other
                   Party the rights granted hereunder, and it shall not enter
                   into any such third party agreement that would prevent it
                   from performing its obligations under this Agreement or
                   granting to the other Party the rights granted hereunder.

           11.1.6  It shall at all times comply with all applicable material
                   laws and regulations relating to its activities under this
                   Agreement.

     11.2  PCAS REPRESENTATIONS AND WARRANTIES. In addition to representations,
           warranties and covenants made elsewhere in this Agreement, PCAS
           represents, warrants and covenants that:

           11.2.1  As of the date of shipment or delivery to ViroPharma of any
                   API manufactured by PCAS, such API shall conform in all
                   material respects to the Specifications, and all applicable
                   laws and regulations, and shall be free from material defects
                   in materials and workmanship.

           11.2.2  As of the date of shipment or delivery to ViroPharma of any
                   API manufactured by PCAS, such API will not be adulterated or
                   misbranded within the meaning of the U.S. Food, Drug, and
                   Cosmetic Act, and will not be an article which may not, under
                   the provisions of Sections 404, 505, or 512 of the U.S. Food,
                   Drug, and Cosmetic Act, be introduced into U.S. interstate
                   commerce.

           11.2.3  PCAS will not use in its performance of its obligations under
                   this Agreement any person, corporation or other entity
                   debarred or suspended under the provisions of the Generic
                   Drug Enforcement Act of 1992, including without limitation,
                   21 U.S.C. Section 335a.

           11.2.4  PCAS does not currently have, and covenants that it will not
                   hire, as an officer or an employee any person who has been
                   convicted of a felony under the laws of the U.S. for conduct
                   relating to the regulation of any drug product under the U.S.
                   Food, Drug, and Cosmetic Act.

           11.2.5  PCAS has the right to assign Inventions to ViroPharma, such
                   Inventions will not infringe the rights of any third parties,
                   and PCAS has obtained an enforceable written agreement from
                   each person providing services under this Agreement
                   transferring all right title and interest in any Invention
                   either directly, or through PCAS, to ViroPharma.

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May 22, 2001                    ViroPharma-PCAS Agreement                Page 18
<PAGE>

     11.3  VIROPHARMA REPRESENTATIONS AND WARRANTIES. In addition to
           representations, warranties and covenants made elsewhere in this
           Agreement, ViroPharma represents, warrants and covenants that:

           11.3.1  ViroPharma owns or otherwise has the right to disclose the
                   Specifications to PCAS.

           11.3.2  PCAS may use the ViroPharma Know How for the purposes of
                   manufacturing the API pursuant hereto and that to the best of
                   ViroPharma's knowledge, such use shall not result in PCAS
                   infringing or misappropriating any third party right thereto.

           11.3.3  ViroPharma has identified potential suppliers of Starting
                   Materials at the following prices:

                   (a)  ********:  $****** /kg; and

                   (b)  ********:  $****** /kg.

12.  LIABILITY.

     12.1  Indemnifications.

           12.1.1  PCAS Indemnification of ViroPharma. PCAS will indemnify,
                   defend and hold harmless ViroPharma and its employees,
                   officers, directors and agents (each, a "ViroPharma
                   Indemnified Party") from and against any and all liability,
                   loss, damage, expense (including reasonable attorneys' fees
                   and expenses) and cost (collectively, a "Liability") that the
                   ViroPharma Indemnified Party may be required to pay to one or
                   more third parties resulting from or arising out of:

                   (a)  any PCAS representation or warranty set forth herein
                        being untrue in any material respect when made;

                   (b)  any claim of any nature, including any products
                        liability claim, directly arising from the failure of
                        API to have been manufactured, processed, prepared,
                        packed, or held in accordance with the Specifications,
                        applicable laws and regulations, or PCAS'
                        representations or warranties hereunder; and/or

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                Page 19
<PAGE>

                   (c)  any negligent act or omission or willful misconduct on
                        the part of PCAS, its employees, officers, directors or
                        agents.

                   except in each case, to the extent caused by the negligence
                   or willful misconduct of ViroPharma or any ViroPharma
                   Indemnified Party.

           12.1.2  VIROPHARMA INDEMNIFICATION OF PCAS. ViroPharma will
                   indemnify, defend and hold harmless PCAS and its employees,
                   officers, directors and agents (each, a "PCAS Indemnified
                   Party") from and against any and all liability, loss, damage,
                   expense (including reasonable attorneys' fees and expenses)
                   and cost (collectively, a "Liability") that the PCAS
                   Indemnified Party may be required to pay to one or more third
                   parties resulting from or arising out of:

                   (a)  any ViroPharma representation or warranty set forth
                        herein being untrue in any material respect when made;

                   (b)  the testing, consumption, promotion, sale or advertising
                        of API, except to the extent arising from the failure of
                        API to have been manufactured, processed, prepared,
                        packed, or held in accordance with the Specifications,
                        applicable laws and regulations, or PCAS'
                        representations or warranties hereunder; and/or

                   (c)  any negligent act or omission or willful misconduct on
                        the part of ViroPharma, its employees, officers,
                        directors or agents.

                   except in each case, to the extent caused by the negligence
                   or willful misconduct of PCAS or any PCAS Indemnified Party.

     12.2  Procedures for Indemnification. If a Party seeks indemnification
           under Section 12.1, it shall inform the other Party (the
           "Indemnifying Party") of a claim as soon as reasonably practicable
           after it receives notice of the claim, shall permit the Indemnifying
           Party to assume direction and control of the defense of the claim
           (including the right to settle the claim solely for monetary
           consideration), and, at the Indemnifying Party's expense, shall
           cooperate as reasonably requested in the defense of the claim. The
           Indemnified Party shall have the right to retain its own counsel,
           subject to the approval of any such outside counsel by the
           Indemnifying Party, with the fees and expenses to be paid by the
           Indemnifying Party if representation of such Party by the counsel
           retained by Indemnifying Party would be inappropriate due to actual
           or potential differing interests between such indemnitee and any
           other party represented by such counsel in such proceedings. The
           Indemnifying Party may not settle such action or claim, or otherwise
           consent to an adverse judgment in such action or claim, without the
           express written consent of the Indemnified Party if such settlement
           or adverse judgment

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                Page 20
<PAGE>

           diminishes the rights or interests of, or imposes any obligation on,
           the Indemnified Party.

     12.3  INSURANCE. Each Party hereby agrees to maintain, during the term of
           this Agreement, insurance with reputable and sound independent
           insurers at commercially reasonable levels of coverage in relation to
           the type, scope and size of business it conducts and to all its
           obligations herein contained and shall give the other Party an
           opportunity from time to time to review the insurance policies so
           that the other Party may satisfy itself that such insurance policies
           are valid, that the premiums are being paid regularly and that the
           policies are kept in full force and effect.

13.  TERMINATION.

     13.1  TERMINATION FOR DIVERGENCE FROM VIROPHARMA QA/QC REQUIREMENTS.

            13.1.1  NOTICE OF COMPLIANCE. Before ViroPharma submits the first
                    Firm Order pursuant to Section 4.3, for a Validation Batch
                    pursuant to Section 3.8, ViroPharma shall provide PCAS with
                    written notice of ViroPharma's determination that the
                    quality assurance, quality control, and GMP compliance
                    functions and standards of PCAS are substantially in
                    compliance with FDA's requirements.

            13.1.2  TERMINATION. If ViroPharma does not provide notice of
                    compliance to PCAS pursuant to Section 13.1.1 by June 29,
                    2001, because ViroPharma concludes that the quality
                    assurance, quality control, and GMP compliance functions and
                    standards of PCAS are not substantially in compliance with
                    FDA's requirements, then on June 29, 2001, ViroPharma may
                    provide PCAS with written notice of termination under this
                    Section 13.1.2 by facsimile, which termination shall be
                    effective on July 6, 2001, or as set forth in Section
                    13.1.3.

            13.1.3  DISPUTE RESOLUTION. If ViroPharma provides notice of
                    termination to PCAS pursuant to Section 13.1.2, and PCAS
                    disagrees with ViroPharma's conclusion that the quality
                    assurance, quality control, and GMP compliance functions and
                    standards of PCAS are not substantially in compliance with
                    FDA's requirements, then PCAS shall notify ViroPharma by
                    July 6, 2001 of its disagreement. By July 13, 2001, the
                    Parties shall agree on an expert in QA/QC and GMP compliance
                    to arbitrate the dispute. If the Parties cannot agree on an
                    expert, then by July 18, 2001, each Party shall select one
                    expert, both of which experts together shall by July 20,
                    2001, select another expert who shall be treated as the
                    expert agreed to by the Parties. Within three (3) weeks of
                    being selected, the expert agreed to by the Parties shall
                    perform an audit of PCAS, and determine whether the quality
                    assurance, quality control, and GMP

--------------------------------------------------------------------------------
May 22, 2001                    ViroPharma-PCAS Agreement                Page 21
<PAGE>

                    compliance functions and standards of PCAS are or are not
                    substantially in compliance with FDA's requirements. If the
                    expert agrees with ViroPharma's assessment, then PCAS shall
                    bear all the costs of such determination under this Section
                    13.1.3, and the Agreement shall be terminated effective upon
                    such decision of the expert. If the expert agrees with PCAS,
                    then ViroPharma shall bear all the costs of such
                    determination under this Section 13.1.3, and the Agreement
                    shall not be terminated.

     13.2  TERMINATION FOR MATERIAL BREACH. A non-defaulting Party shall have
           the right to terminate this Agreement after written notice to the
           other that the other is in material breach of this Agreement (the
           "Defaulting Party"), unless the Defaulting Party cures the breach
           before the expiration of sixty days after such written notice.

     13.3  TERMINATION FOR INSOLVENCY. Either Party may terminate this Agreement
           if, at any time, the other Party shall file in any court or agency
           pursuant to any statute or regulation of any state or country, a
           petition in bankruptcy or insolvency or for reorganization or for an
           arrangement or for the appointment of a receiver or trustee of the
           Party or of its assets, or if the other Party proposes a written
           agreement of composition or extension of its debts, or if the other
           Party shall be served with an involuntary petition against it, filed
           in any insolvency proceeding, and such petition shall not be
           dismissed within sixty days after the filing thereof, or if the other
           Party shall propose or be a party to any dissolution or liquidation,
           or if the other Party shall make an assignment for the benefit of
           creditors.

     13.4  TERMINATION FOR DEBARMENT. ViroPharma may terminate this Agreement
           effective immediately upon notice if at any time during the term of
           this Agreement PCAS becomes debarred or receives notice of action or
           threat of action with respect to its debarment. PCAS shall notify
           ViroPharma immediately if at any time during the term of this
           Agreement PCAS becomes debarred, or receives notice of action or
           threat of action with respect to its debarment.

     13.5  TERMINATION FOR DELAY IN REGULATORY APPROVAL. At any time before
           June1, 2001 ViroPharma may terminate this Agreement upon fifteen days
           advance written notice if ViroPharma reasonably believes that
           regulatory approval of pleconaril is likely to be delayed
           significantly beyond current projections. ViroPharma shall pay PCAS
           $630,000 within thirty days of exercising its right of termination
           under this Section 13.5.

     13.6  TERMINATION FOR ADVERSE REGULATORY ACTION. ViroPharma may terminate
           this Agreement upon sixty days advance written notice if the FDA or
           any other Regulatory Authority directly or indirectly prohibits or
           prevents the manufacture or sale of Pleconaril or any finished dosage
           form containing Pleconaril.

     13.7  TERMINATION UPON PURCHASE OF ************** TONS OF API. If at any
           time before December 31, 2003, the total amount of API that
           ViroPharma has purchased from PCAS under this Agreement exceeds
           ********** kg, ViroPharma may terminate this Agreement upon three (3)
           months advance written notice.

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May 22, 2001                    ViroPharma-PCAS Agreement                Page 22
<PAGE>

     13.8  EFFECT OF TERMINATION.

           13.8.1  GENERAL. Upon the expiration or any termination of this
                   Agreement: (a) all licenses under this Agreement shall be
                   terminated; and (b) upon the written request of ViroPharma,
                   PCAS shall destroy and shall not retain any copies of any
                   Confidential Information provided by ViroPharma hereunder,
                   except for one copy to be retained by legal counsel solely
                   for archival purposes.

           13.8.2  SURVIVAL OF RIGHTS. Termination or expiration of this
                   Agreement shall not affect any rights to payment or other
                   rights that accrued before the date of termination or
                   expiration. The terms of the following Articles and Sections
                   shall survive any termination or expiration of this
                   Agreement: 3.5, 4.4, 5.3, 6.1.2, 8.2, 8.4-8.6, 8.8, 9, 10,
                   11.2-11.3, 12, and 13.8.

           13.8.3  RIGHTS NOT EXCLUSIVE. All rights to terminate, and rights
                   upon termination, provided for either Party in this Agreement
                   are in addition to other remedies in law or equity which may
                   be available to either Party.

14.  GENERAL TERMS.

     14.1  ENTIRE AGREEMENT. This Agreement constitutes and contains the
           complete, final and exclusive understanding and agreement of the
           Parties and cancels and supersedes any and all prior negotiations,
           correspondence, understandings and agreements, whether oral or
           written, between the Parties respecting the subject matter hereof and
           thereof.

     14.2  AMENDMENT. No amendment, modification or supplement of any provision
           of this Agreement shall be effective unless made in writing and
           signed by a duly authorized officer of each Party.

     14.3  ASSIGNMENT. Neither this Agreement nor any interest hereunder shall
           be assignable by either Party without the prior written consent of
           the other Party, except for an assignment by a Party to a successor
           to substantially all of the business of such Party or to an Affiliate
           of such Party. This Agreement shall be binding upon the successors
           and permitted assigns of the Parties. Any assignment not in
           accordance with this Section 14.3 shall be void.

     14.4  WAIVER. No provision of the Agreement shall be waived by any act,
           omission or knowledge of a Party or its agents or employees except by
           an instrument in writing expressly waiving such provision and signed
           by a duly authorized officer of the waiving Party.

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May 22, 2001                    ViroPharma-PCAS Agreement                Page 23
<PAGE>

     14.5  SEVERABILITY. If any part of this Agreement is for any reason held to
           be invalid, illegal or unenforceable, the Agreement shall be
           construed as if such part had never been contained in this Agreement,
           and there shall be deemed substituted for such part a provision that
           will most nearly carry out the intent of the Parties in this
           Agreement.

     14.6  GOVERNING LAW. This Agreement shall be governed by and interpreted in
           accordance with the substantive laws of the Commonwealth of
           Pennsylvania, U.S.A., without regard to conflict of law principles
           thereof or of any other jurisdiction.

     14.7  NOTICES. All notices, requests and other communications required
           under this Agreement, shall be in writing and, unless otherwise
           provided herein, shall be deemed to have been given:

           a.  when delivered by hand;

           b.  if communicated by facsimile, cable or similar electronic means,
               at the time that receipt thereof has been confirmed by return
               electronic communication or signal that the message has been
               received;

           c.  five days after being deposited in the United States mail,
               postage prepaid, certified, return receipt requested; or

           d.  three days after being deposited with an internationally
               recognized overnight courier, return receipt requested.

           Unless otherwise agreed, notices shall be addressed to the parties as
           follows:

           If to ViroPharma:  ViroPharma Incorporated
                              Attn: Director of Manufacturing
                              405 Eagleview Boulevard
                              Exton, PA  19341
                              U.S.A.
                              Fax:  (610) 458-7380

           With a copy to:    ViroPharma Incorporated
                              Attn: General Counsel
                              405 Eagleview Boulevard
                              Exton, PA  19341
                              U.S.A.
                              Fax:  (610) 458-7380

           If to PCAS:        PCAS
                              Attn:  Directeur General
                              Boite Postale 181
                              91161 Longjumeau Cedex
                              France
                              Fax:  33 (0)1 64 48 23 19

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May 22, 2001                    ViroPharma-PCAS Agreement                Page 24
<PAGE>

           Either party may change the facsimile number, name or address to
           which notices should be sent by a notice given to the other party in
           the manner set forth above.

     14.8  LANGUAGE. All documents, records or notices required under this
           Agreement shall be kept or made in English, or shall be translated
           into English at ViroPharma's request and at the expense of PCAS,
           except for current working procedures such as batch records, working
           instructions and SOP's.

     14.9  FORCE MAJEUR. Neither Party shall be liable to the other for delay or
           failure in the performance of the obligations on its part contained
           in this Agreement if and to the extent that such failure or delay is
           due to circumstances beyond its control which it could not have
           avoided by the exercise of reasonable diligence. It shall notify the
           other Party in writing promptly should such circumstances arise (the
           "Force Majeure Notice"), giving an indication of the likely extent
           and duration thereof, and shall use all commercially reasonable
           efforts to resume performance of its obligations as soon as
           practicable. In the event that such Party has been unable to perform
           its obligations under the Agreement within sixty days of the Force
           Majeure Notice, the other Party shall have the right to terminate
           this Agreement without penalty.

     14.10 RELATIONSHIP OF THE PARTIES. Both Parties are independent contractors
           under this Agreement. Nothing in this Agreement creates an
           employment, agency, joint venture or partnership relationship between
           the Parties hereto or any of their agents or employees, or any other
           legal arrangement that would impose liability upon one Party for the
           act or failure to act of the other Party.

     14.11 COUNTERPARTS. This Agreement may be executed in any number of
           counterparts, each of which need not contain the signature of more
           than one Party but all such counterparts taken together shall
           constitute one and the same agreement.

     14.12 REPRESENTATION BY LEGAL COUNSEL. Each Party hereto represents that it
           has been represented by legal counsel in connection with this
           Agreement and acknowledges that it has participated in the drafting
           hereof. In interpreting and applying the terms and provisions of this
           Agreement, the Parties agree that no presumption shall exist or be
           implied against the Party that drafted such terms and provisions.

IN WITNESS WHEREOF, the Parties hereto have duly executed this Agreement as of
the date first above written.

VIROPHARMA INCORPORATED                  PCAS

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May 22, 2001                    ViroPharma-PCAS Agreement                Page 25
<PAGE>

By: /s/ Michel de Rosen                    By: /s/ A. Galigne  /s/ B.J. Pons
   --------------------------                 ------------------------------
     Michel de Rosen                       Name: A. Galigne     B.J. Pons
     President & CEO                            ----------------------------
                                           Its: Director, Pharma Synthesis
                                               -----------------------------

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May 22, 2001                    ViroPharma-PCAS Agreement                Page 26
<PAGE>

                               EXHIBIT 1.16(A-B)
                             SUMMARY SPECIFICATIONS

NDA Commercial Specification for Pleconaril Drug Substance (Unmicronized)

=============================================================================
Tests                      Method Number         Acceptance Criteria
-----------------------------------------------------------------------------
DESCRIPTION                 *********                **********
-----------------------------------------------------------------------------
Identification              *********                **********

-----------------------------------------------------------------------------
Assay (HPLC)                *********                **********
-----------------------------------------------------------------------------
Chromatographic Impurity    *********                **********
 (HPLC)
-----------------------------------------------------------------------------
Residue on Ignition         *********                **********
-----------------------------------------------------------------------------
Heavy Metals                *********                **********
-----------------------------------------------------------------------------
Polymorphic Form (DSC)/1/   *********                **********
-----------------------------------------------------------------------------
Melting Range               *********                **********
(DSC)
=============================================================================

/1/ : Carried out by a contract laboratory under the responsibility of
      ViroPharma

Appendix: In-House Tests for *******  Drug Substance  (Unmicronized)

=============================================================================
Tests                           Methods          Internal Guidelines
-----------------------------------------------------------------------------

Water                          *********             **********
(Karl Fischer)
-----------------------------------------------------------------------------
 *************                 *********             **********
=============================================================================
1 : Carried out by a contract laboratory under the responsibility of
    ViroPharma

--------------------------------------------------------------------------------
May 22, 2001                            Exhibit 1.16(b)                   Page 1
<PAGE>

NDA Commercial Specification for ***********

==============================================================================
   Tests                        Method Number         Acceptance Criteria
------------------------------------------------------------------------------
Description                       *********                **********
------------------------------------------------------------------------------
Identification (IR)               *********                **********
------------------------------------------------------------------------------
Water (Karl Fischer)              *********                **********
------------------------------------------------------------------------------
Chromatographic Impurity (HPLC)   *********                **********
==============================================================================

NDA Commercial Specification for *******

==============================================================================
TESTS                     Method Number         Acceptance Criteria
------------------------------------------------------------------------------
DESCRIPTION                 *********                 **********
------------------------------------------------------------------------------
IDENTIFICATION (IR)         *********                 **********
------------------------------------------------------------------------------
WATER (KARL FISCHER)        *********                 **********
------------------------------------------------------------------------------
CHROMATOGRAPHIC IMPURITY    *********                 **********
 (HPLC)
==============================================================================

--------------------------------------------------------------------------------
May 22, 2001                            Exhibit 1.16(b)                   Page 2
<PAGE>

NDA Commercial Specification for ********

===============================================================================
TESTS                           METHOD NUMBER          ACCEPTANCE CRITERIA
-------------------------------------------------------------------------------
DESCRIPTION                       *********                **********
-------------------------------------------------------------------------------
IDENTIFICATION (IR)               *********                **********
-------------------------------------------------------------------------------
CHROMATOGRAPHIC IMPURITY          *********                **********
 (GC)
===============================================================================

APPENDIX: IN-HOUSE TEST FOR ********

===============================================================================
TESTS                              METHODS                INTERNAL GUIDELINES
-------------------------------------------------------------------------------
CHROMATOGRAPHIC IMPURITY          *********                    **********
 (GC)
===============================================================================

NDA Commercial Specification for ********

===============================================================================
Tests                     Method Number          Acceptance Criteria
-------------------------------------------------------------------------------
DESCRIPTION                 *********                **********
-------------------------------------------------------------------------------

IDENTIFICATION (IR)         *********                **********
-------------------------------------------------------------------------------
CHROMATOGRAPHIC IMPURITY    *********                **********
 (GC)
-------------------------------------------------------------------------------
ASSAY (HPLC)                *********                **********
-------------------------------------------------------------------------------
WATER (KARL FISCHER)        *******                  **********
===============================================================================

--------------------------------------------------------------------------------
May 22, 2001                            Exhibit 1.16(b)                   Page 3
<PAGE>

                                 EXHIBIT 1.20
                              VALIDATION PROTOCOL

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

VALIDATION PROTOCOL AND VALIDATION PLAN

  -----------------------------------------------------------------------------
  |  Production:                     PLECONARIL                                |
  |----------------------------------------------------------------------------|
  |  Validation type:                Prospective validation                    |
  |----------------------------------------------------------------------------|
  |  Initial references:             Validation report VALPLE1/ 08/10/99, see  |
  |                                  also chapters 3 and 9 of the present      |
  |                                  protocol.                                 |
  |----------------------------------------------------------------------------|
  |  Applicable SOP's:               Validation of New Productions             |
  |                                  Quality manual sections 4.4, 4.9 and 4.10 |
  -----------------------------------------------------------------------------

  Approved by:

  ---------------------------------------------------------     --------------
  Claude Becker, Quality Manager, Seloc                              Date

  ---------------------------------------------------------     --------------
  Jean Marie Schneider, R&D Manager, Seloc                           Date

  ---------------------------------------------------------     --------------
  Muriel Janvion, Quality Control Supervisor, Seloc                  Date

  ---------------------------------------------------------     --------------
  Benoit Peure, Chemical Development, Seloc                          Date

  ---------------------------------------------------------     --------------
  Kimm Galbraith, Manufacturing, ViroPharma                          Date

  ---------------------------------------------------------     --------------
  Cynthia Gallagher, CMC, ViroPharma                                 Date

  ---------------------------------------------------------     --------------
  Crispin Cebula, Chemical Development, ViroPharma                   Date

  ---------------------------------------------------------     --------------
  Valerie Brower, Quality Manager, ViroPharma                        Date

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                         Page 1
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

TABLE OF CONTENTS

Table of Contents..............................................................2

1   Objective and Scope........................................................3

2   Responsibilities...........................................................3

    2.1. Research and Development..............................................3
    2.2. Production............................................................3
    2.3. Quality Control.......................................................3
    2.4. Quality Assurance.....................................................4
    2.5. ViroPharma............................................................4

3   Type of Validation.........................................................4

4   Number of Validation Batches...............................................5

5   Quality of Materials.......................................................5

6   Process Description........................................................5

7   Process Equipment..........................................................6

8   Specifications.............................................................6

    8.1. In Process Controls...................................................6
    8.2. Starting Materials....................................................7
    8.3. Intermediates.........................................................8
    8.4. Pleconaril Drug Substance.............................................8

9   Process Parameters.........................................................9

10  Sampling Plans............................................................10

11  Validation Review and Validation Report...................................11

12  Validation Acceptance Criteria............................................12

13  Process Validation Failure................................................13

14  Validation Plan...........................................................14

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 2
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

1    OBJECTIVE AND SCOPE

     The objective of this Protocol is to describe the commercial manufacturing
     process for the production of pleconaril drug substance at the 600 kg
     scale. It also defines the requirements for process validation and the
     acceptance criteria for this process validation. The successful completion
     of this Protocol will provide assurance that the commercial manufacturing
     process for pleconaril will consistently produce material that meets the
     Specifications for pleconaril, including polymorph form (Form III), and is,
     therefore, validated.

2    RESPONSIBILITIES

     2.1. RESEARCH AND DEVELOPMENT

          The Research and Development Department will:

              Establish the Summary Development Report and provide Quality
              Assurance with the information necessary for the development of
              the Validation Protocol.

              Review and approve the Validation Protocol prior to execution.

              Assist the Production Department during the manufacture of the
              validation batches.

              Review and approve the final Validation report.

     2.2. PRODUCTION

          The Production Department will:

              Review and approve the Validation Protocol prior to execution.

              Review and approve the Master Batch Records prior to execution.

              Manufacture the validation batches in accordance with the approved
              Master Batch Records and the specific instructions of this
              Validation Protocol.

              Remove the in-process control samples according to the sampling
              plan during manufacturing for analysis.

              Review the executed Batch Records for completeness and accuracy
              prior to submission to the Quality Assurance Department for final
              review and approval.

              Review and approve the final Validation report.

     2.3. QUALITY CONTROL

          The Quality Control Department will:

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 3
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

              Review and approve the Validation Protocol prior to execution.

              Receive in-process samples for analysis.

              Remove samples of intermediate or final API for release testing.

              Test the in-process control samples as well as the samples for the
              final product of each manufacturing step in accordance with the
              validated and/or approved analytical methods.

              Review the analytical results for completeness and accuracy,
              prepare the analytical reports prior to submission to Quality
              Assurance for final review and approval.

              Review and approve the final Validation report.

     2.4. QUALITY ASSURANCE

          The Quality Assurance Department will:

              Prepare and approve the Validation Protocol prior to execution.

              Review and approve the Master Batch Records prior to execution.

              Review and approve the executed Batch Records and the analytical
              results for completeness, accuracy and compliance with the Master
              Batch Records, analytical methods and current Good Manufacturing
              Practices.

              Prepare and approve the final Validation report.

     2.5. VIROPHARMA

          ViroPharma Incorporated as Sponsor will:

              Review and approve the Validation Protocol prior to execution.

              Review and approve the Master Batch Records prior to execution.

              Review and approve the executed Batch Records.

              Review and approve the final Validation report.

3    TYPE OF VALIDATION

     The validation is a prospective validation of the three-step synthesis of
     pleconaril. The validation will verify the previous validation results for
     steps 1 and 2 with a 1.5 time batch size increase in these steps and to
     demonstrate that control of crystallization will consistently produce
     polymorphic form III of pleconaril.

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 4
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

4    NUMBER OF VALIDATION BATCHES

     The validation will be carried out on all three (3) steps of the synthesis
     on the new production campaign. The relevant data will be collected for all
     the batches produced during that additional campaign. The campaign will
     consist in 5 batches of both 1st and 2nd steps and 4 batches of the 3rd
     step.

     After completion of each batch, the batch record will be reviewed to
     determine the effect of any modifications and/or deviations to the
     procedure described in the applicable Master Batch Record (MBR) on the
     validation. For a successful validation, at least three (3) consecutive
     batches of each step will be produced without deviations of the critical
     process parameters. In addition, the three consecutive batches of each step
     must conform to the critical quality attributes.

     If any step requires modifications to the process and MBR, this validation
     protocol will be amended and additional batch(es) will be produced so that
     the validation includes three consecutive batches by the amended process
     and if a validation batch fails for reasons unrelated to process
     performance (e.g., power failure or equipment or equipment breakdown), that
     batch will be removed from the validation study and an additional batch
     will be produced, which will be considered consecutive to the batch
     preceding the batch that failed for non-process related reasons.

5    QUALITY OF MATERIALS

     Only fresh, not recovered, solvents are used . All reagents, solvents and
     other materials used in this validation will meet their currently approved
     specifications.

6    PROCESS DESCRIPTION

STEP 1: PREPARATION OF *********** (**************)

**************

STEP 2: PREPARATION OF *********** (**************)

**************

STEP 3: PREPARATION OF *********** (**************)

**************

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 5
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

7    PROCESS EQUIPMENT

     Major equipment used for the manufacture of pleconaril is specified in the
     batch record. The equipment is multi-purpose, has been previously qualified
     and is subject to periodic calibrations.

8    SPECIFICATIONS

     The specifications for In Process Controls, Pleconaril, the two
     intermediates and the starting materials are listed in the tables below:

     8.1.IN PROCESS CONTROLS (IPC's)

     The following are the acceptance criteria for IPC's.

     =========================================================================
      IPC # AND
      DESCRIPTION          METHOD NUMBER     ACCEPTANCE CRITERIA
      ------------------------------------------------------------------------
      203-1
      Chromatographic      ***************   ***************
      Impurity
      ------------------------------------------------------------------------
      203-1.5
      Loss on drying       ***************   ***************
      ------------------------------------------------------------------------
      203-2
      Chromatographic      ***************   ***************
      Impurity
      ------------------------------------------------------------------------
      203-3
      Water (Karl          ***************   ***************
      Fischer)
      ------------------------------------------------------------------------
      203-4
      Residual             ***************   ***************
      solvents
     =========================================================================

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 6
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

     8.2. STARTING MATERIALS

          The following are the acceptance criteria for the starting materials.

          *********** (************)

         =======================================================================
          TESTS                   METHOD NUMBER           ACCEPTANCE CRITERIA
         -----------------------------------------------------------------------
          Description             ***************         ***************
         -----------------------------------------------------------------------
          Identification (IR)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Chromatographic
          Impurity (GC)           ***************         ***************
         -----------------------------------------------------------------------
          Assay (HPLC)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Water (Karl
          Fischer)                ***************         ***************
         =======================================================================

          ************ (**************)

         =======================================================================
          TESTS                   METHOD NUMBER           ACCEPTANCE CRITERIA
         -----------------------------------------------------------------------
          Description             ***************         ***************
         -----------------------------------------------------------------------
          Identification (IR)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Chromatographic
          Impurity (GC)           ***************         ***************
         =======================================================================

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 7
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

     8.3. INTERMEDIATES

          The following are the acceptance criteria for each intermediate.

          ************ (**************)
         =======================================================================
          TESTS                   METHOD NUMBER           ACCEPTANCE CRITERIA
         -----------------------------------------------------------------------
          Description             ***************         ***************
         -----------------------------------------------------------------------
          Identification (IR)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Water (Karl
          Fischer)                ***************         ***************
         -----------------------------------------------------------------------
          Chromatographic
          Impurity (HPLC)         ***************         ***************
         =======================================================================

          ************ (**************)
         =======================================================================
          TESTS                   METHOD NUMBER           ACCEPTANCE CRITERIA
         -----------------------------------------------------------------------
          Description             ***************         ***************
         -----------------------------------------------------------------------
          Identification (IR)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Water (Karl
          Fischer)                ***************         ***************
         -----------------------------------------------------------------------
          Chromatographic
          Impurity (HPLC)         ***************         ***************
         =======================================================================

     8.4. PLECONARIL DRUG SUBSTANCE

          The following are the acceptance criteria for pleconaril drug
          substance.

         PLECONARIL DRUG SUBSTANCE (UNMICRONIZED), ************

         =======================================================================
          TESTS                   METHOD NUMBER           ACCEPTANCE CRITERIA
         -----------------------------------------------------------------------
          Description
                                  ***************         ***************
         -----------------------------------------------------------------------
          Identification
                                  ***************         ***************
         -----------------------------------------------------------------------
          Assay (HPLC)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Chromatographic
          Impurity (HPLC)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Residue on
          Ignition
                                  ***************         ***************
         -----------------------------------------------------------------------
          Heavy Metals            ***************         ***************
         -----------------------------------------------------------------------
          Polymorphic
          Form III (DSC)
                                  ***************         ***************
         -----------------------------------------------------------------------
          Melting Range
          (DSC)                   ***************         ***************
         =======================================================================

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 8
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

9    PROCESS PARAMETERS - CRITICAL PROCESS PARAMETERS

     The critical process parameters for the manufacture of pleconaril are
     discussed in:

     o  Validation Plan and Validation Protocol for Pleconaril - Limay,
        June 29, 1998
     o  Pleconaril Production Batches - Development Report, B. Peure, Seloc,
        September 21, 1999

     o  Pleconaril Process Control - Critical Parameter Justification,
        C. Becker, February 2, 2000
     o  Summary of Development Report, C. Becker February 12, 2001

     As defined during the development of the manufacturing process for
     pleconaril, the following parameters are critical to the manufacturing
     process:

     PROCESS STEP 1:

     No critical parameters.

     PROCESS STEP 2:

     o  The addition of ************** will be within ************** % of the
        ******* ratio target.

     o  The water content of isolated ************** (**************) will be
        ************** %

     PROCESS STEP 3:

     o  Temperature prior to ***********: ********  to ******** (degree)C

     o  Seed amount will be ***%-*****% of target batch size and seed quality
        will be ********% form III determined by DSC.

     o  Temperature and time for drying: ***** to *******(degree)C for Not Less
        Than ***** hours

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 9
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

10   SAMPLING PLANS

     Sampling of raw materials, in-process control materials, intermediates and
     final product will be carried out according with current SOPs. Any specific
     sampling is indicated in the batch instructions.

     The proposed sampling plan for the validation batches is as follows:

     PROCESS STEP 1

     .  IPC#203-1 Samples taken and analyzed at *********** hours to profile
        completion of reaction. When IPC#203-1 results are ********%
        ***********, then the reaction will be cooled and no further samples
        taken. The IPC results from all three validation batches will be
        evaluated in conjunction with previous pilot and production batches to
        confirm that the target reaction time is consistently between ********
        hours.

     .  At least three samples are taken from each batch (first centrifuge shot,
        half-way through-centrifugation and last centrifuge shot) and each
        sample analyzed individually for impurities (method no. 61834.000) to
        evaluate efficiency of the washing procedure and an LOD (IPC 203-1.5) to
        evaluate centrifugation efficiency.

     PROCESS STEP 2

     .  After drying, a representative sample from the first drum, middle drum
        and last drum of total number of drums will be taken and each sample
        analyzed individually for water content (IPC#203-3).

     PROCESS STEP 3

     .  During and after drying and sieving, sampling and testing are carried
        out according to the following plan:

                                 Production          Batch             Number
                                 ----------          -----             ------
            Drying time/1/           5                 6                  7
     ---------------------------------------------------------------------------
               24 h                  B                 B                  B
     ---------------------------------------------------------------------------
               32 h*                 A                 A                  A
     ---------------------------------------------------------------------------
               40 h*                 A                 A                  A
     ---------------------------------------------------------------------------
               48 h*                 A                 A                  A
     ---------------------------------------------------------------------------
               60 h*                 A                 A                  A
     ---------------------------------------------------------------------------

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 10
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

     ---------------------------------------------------------------------------
               72 *                  A                 A                  A
     ---------------------------------------------------------------------------
         After IPC passes
        remove from dryer            B                 B                  B
           and sample
     ---------------------------------------------------------------------------

          After sieving              C                 C                  C
     ---------------------------------------------------------------------------

/1/ All sampling times are plus or minus 1 hour
*If necessary (IPC results exceed specs).

Sampling:

 .  for samples A and B, the sampling is carried out as per SOP G3-033

 .  for sample C (final sampling of the batch after sieving), a representative
   sample from the first drum, middle drum and last drum of total number of
   drums will be taken per SOP G3-032.

Testing; according to the sampling identification, the following testing is
carried out:

A:    Residual solvents  (method 3482)

B:    Residual solvents  (method 3482)
      Chromatographic purity  (Method-1 63843DS.003)
      Polymorphic form III (DSC) (Method 63843DS.600)

C:    Residual solvents  (method 3482) and full release testing as per
      section 8.4

11   VALIDATION REVIEW AND VALIDATION REPORT

     The studies, documents and data listed in the validation plan will be
     subject to periodic reviews and a final review. A validation report will be
     written. The final review and the approval of the validation report will be
     carried out by the functions involved for the approval of the present
     protocol as defined in section 2.

     The validation report will include the following, at a minimum:

     Copy of the Control Sheets of the Executed Batch Records.

     o  Listing of all modifications and deviations from the MBR for each batch
        for each step, as well as an evaluation of the impact on the validation
        of each modification and deviation.

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 11
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

     o  Table listing steps with defined process parameters, the acceptance
        criteria for each listed process parameter, the actual conditions for
        those parameters for each batch and an evaluation as to whether the
        actual conditions met the acceptance criteria.

     o  Tables with the analytical results of the testing in the quality
        specifications for Intermediates and pleconaril, as well as an
        evaluation as to whether each batch met the acceptance criteria.

     o  Evaluation to determine that each step met all acceptance criteria and
        is considered validated.

     o  Conclusions.

   The complete validation file will contain the above validation report and all
   documentation collected.

12   VALIDATION ACCEPTANCE CRITERIA

     The validation acceptance criteria are as follows:

     o  Acceptance of each executed batch record demonstrating that the process
        parameters have been met within the defined ranges.

     o  The two starting materials, two intermediates and the final API will
        meet all specification acceptance criteria as outlined in section 8.

     o  The following samples described under the sampling plan section will
        meet the following acceptance criteria:

     12.1. PROCESS STEP 1:

           .  IPC 203-1 Samples: IPC 203-1 results are ********% ***********.
              The IPC results from all three validation batches will be
              evaluated in conjunction with previous pilot and production
              batches to confirm that the target reaction time is consistently
              ****** hours.

           .  Centrifuge Shots: Each sample will be analyzed for residual
              solvents by LOD (IPC 203-1.5). Acceptance criteria: Any individual
              LOD value across all batches will not be ************%.

     12.2. PROCESS STEP 2:

           .  IPC 203-2 Samples: IPC 203-2 results are *********% *************.

           .  Samples from Dryer: Each sample will be analyzed using the most
              current version of the water content method (IPC#203-3).
              Acceptance criteria: Water content ********%

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 12
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

     12.3. PROCESS STEP 3:

           .  Samples from the Dryer: The samples are analyzed according to the
              plan given in section 10 - process step 3. The samples will
              validate

               -  Purity, polymorphic form at "middle" (about 24 hours), end of
                  drying and after sieving

               -  That the IPC will determine end of drying and batch
                  homogeneity.

              The intention of this plan is not to validate a certain drying
              time.

           .  Samples from Drums: Each sample will be analyzed using the most
              current version of methods listed in section 8.4. Acceptance
              criteria: Each sample must meet all specifications acceptance
              criteria listed in section 8.4. of this protocol.

           .  The analytical results on both samplings will be evaluated for the
              incidence of drying and sieving on the polymorphysm and on the
              impurities profile.

13   PROCESS VALIDATION FAILURE

     If any step fails to meet the process validation criteria specified in
     Section 12, an investigation will be carried out to determine the cause of
     the failure. If necessary, additional developmental work may be carried
     out. Based on the results of the investigation and any additional work,
     this protocol will be amended to describe the additional work required to
     complete the validation.

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 13
<PAGE>

Protocol number                      Process Validation Protocol-PLECONARIL-DATE

<TABLE>
<CAPTION>
14   VALIDATION PLAN - Studies, Activities, Documentation and responsibilities
<S>    <C>                                                                            <C>
--------------------------------------------------------------------------------------------------------
#      STUDIES / ACTIVITIES / DOCUMENTS                                                 RESPONSIB.

--------------------------------------------------------------------------------------------------------
 1     Specifications and specifications change history                                 MJ
--------------------------------------------------------------------------------------------------------
 2     Review of analytical data of raw material prior to batches launches              MJ
--------------------------------------------------------------------------------------------------------
 3     Follow up  of specific additional IPC sampling and relative additional           BP
       instructions to the Batch Manufacturing Instructions
--------------------------------------------------------------------------------------------------------
 4     Follow up of specific cleaning validation sampling and update of cleaning        BP /  BD
       validation matrix
--------------------------------------------------------------------------------------------------------
 5     Production review of executed Batch Records and evaluation of deviations         BD
       prior to submission to QA and  reporting on the Batch Records control forms
--------------------------------------------------------------------------------------------------------
 6     Shipment of samples to be studied for polymorphysm (DSC)                         MJ
--------------------------------------------------------------------------------------------------------
 7     Follow up analytical work for drying validation                                  SF
--------------------------------------------------------------------------------------------------------
 8     Review of the executed Batch Records and related analytical results              JLH
       QA Batch approval
--------------------------------------------------------------------------------------------------------
 9     Analytical profiles for intermediates and final product - Chromatographic        MJ / SF
       profiles
       Summaries for drying and cleaning validation
--------------------------------------------------------------------------------------------------------
10     Intermediate reviews and actions in case of deviations on individual             BP / MJ / CB
       intermediate or API batches
--------------------------------------------------------------------------------------------------------
11     Analytical data summary tables                                                   MJ
--------------------------------------------------------------------------------------------------------
12     Global review of data and documentation relative to the validation batches       BP / MJ / CB /
                                                                                        JMS
--------------------------------------------------------------------------------------------------------
13     Preparation and approval of the final Validation Report including the Summary    BP / MJ / CB /
       of Validation.                                                                   JMS
--------------------------------------------------------------------------------------------------------
</TABLE>

Responsibilities (full names):

JMS     Jean Marie SCHNEIDER                 R&D Manager

SF      Sandrine FERAUD                      Analytical Methods Engineer

MJ      Muriel JANVION                       Quality Control Supervisor

BD      Bruno DOUGUEDROIT                    Chemical Development Technician

BP      Benoit PEURE                         Chemical Development Engineer

JLH     Jean Luc HELLO                       Quality Assurance Supervisor

CB      Claude BECKER                        Quality Manager

--------------------------------------------------------------------------------
May 22, 2001                         Exhibit 1.20                        Page 14
<PAGE>

                                  EXHIBIT 4.1
                       Rolling Annual Forecast by Quarter

                                     PCAS
                   Quarterly Forecasted Material Requirements
                        July 2001 through December 2002

   Quarter            1st         2nd         3rd         4th       Total
------------------------------------------------------------------------------
Calendar Year 2001
  Forecast (kg)      ******      ******      ******      ******     ******
     Batches         ******      ******      ******      ******     ******
------------------------------------------------------------------------------
Calendar Year 2002
  Forecast (kg)      ******      ******      ******      ******     ******
     Batches         ******      ******      ******      ******     ******
------------------------------------------------------------------------------

Assumes a yield and order quantity of ******* kg per batch

--------------------------------------------------------------------------------
May 22, 2001                           Exhibit 4.1                        Page 1
<PAGE>

                                  EXHIBIT 6.4
                       (Euro)/$ EXCHANGE RATE - EFFECTIVE DATE

The (Euro)/$ Exchange Rate on the Effective Date is: 1.140

--------------------------------------------------------------------------------
May 22, 2001                           Exhibit 6.4                        Page 1

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