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[On Letterhead of The Chase Manhattan Bank]
Exhibit 4.2
June 15, 2000
John Nuveen & Co. Incorporated
333 West Wacker Drive
Chicago, Illinois 60606
Re: Nuveen Unit Trusts--Series 90
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Dear Sirs:
The Chase Manhattan Bank is acting as Evaluator for the series of Nuveen
Unit Trust set forth above (the "Trust"). We enclose a list of the Securities to
be deposited in the Trust on the date hereof. The prices indicated therein
reflect our evaluation of such Securities as of close of business on June 14,
2000 in accordance with the valuation method set forth in the Standard Terms and
Conditions of Trust for Nuveen Unit Trust Series 4 and subsequent. We consent to
the reference to The Chase Manhattan Bank as the party performing the
evaluations of the Trust Securities in the Registration Statement (No.
333-34288) filed with the Securities and Exchange Commission with respect to the
registration of the sale of the Trust Units and to the filing of this consent as
an exhibit thereto.
Very truly yours,
/s/ Jennifer Polintan
Assistant Treasurer
