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                                                                     Exhibit 8.1

               [Letterhead of Orrick, Herrington & Sutcliffe, LLP]


                               February 20, 2001



PPL Montana, LLC
303 North Broadway,
Suite 400
Billings, Montana  59101

Ladies and Gentlemen:

        We are acting as legal counsel to PPL Montana, LLC. (the "Company"), a
Delaware limited liability company, in connection with the offer to exchange
(the "Exchange Offer") new pass through trust certificates (herein referred to
as the "New Pass Through Trust Certificate") for an equal principal amount of
existing 8.903% Pass Through Trust Certificates due 2020, (the "Existing Pass
Through Trust Certificates"), and in connection with the preparation of the
prospectus (the "Prospectus") contained in the registration statement on Form
S-4 (the Registration Statement") filed with the Securities and Exchange
Commission by the Company for the purpose of registering the New Pass Through
Trust Certificates under the Securities Act of 1933, as amended (the "Act").

        In rendering our opinion expressed below, we have assumed that all of
the transactions contemplated by the Exchange Offer and described in the
Registration Statement did, in fact, occur in accordance with the terms and
descriptions thereof.

        Based upon the foregoing, and subject to the assumptions and other
limitations set forth in the discussion in the Registration Statement under the
caption "Material U.S. Federal Income Tax Consequences," it is our opinion that,
although such discussion does not address all of the tax consequences of the
Exchange Offer or of owning and disposing of the new pass through trust
certificates, it does address the material U.S. federal income tax consequences
(other than those consequences that may be material to an investor based on its
particular tax situation) and, insofar as it describes matters of law or legal
conclusions for holders, constitutes our opinion with respect thereto and it is
accurate in all material respects.

        We express no opinion as to any matter other than the opinion set forth
above. Our opinion is based on the Internal Revenue Code of 1986, as amended,
Treasury regulations promulgated thereunder, and administrative and judicial
interpretations thereof, all as in effect on the date hereof. The conclusions
reached in this opinion may change as a result of changes in any of the
foregoing.

        We hereby consent to the use of our name under the captions "Material
U.S. Federal Income Tax Consequences" and "Legal Matters" in the Prospectus
forming part of the
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Registration Statement and to the filing of this opinion as an exhibit to the
Registration Statement.


                                       Very truly yours,


                                       /s/ Orrick, Herrington & Sutcliffe, LLP


                                       Orrick, Herrington & Sutcliffe, LLP













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