INTERSTATE POWER AND LIGHT COMPANY (an Iowa corporation) 6.30% SENIOR DEBENTURES DUE 2034 PURCHASE AGREEMENT Dated: May 3, 2004Purchase Agreement • May 5th, 2004 • Interstate Power & Light Co • Electric & other services combined • New York
Interstate Power and Light Company, an Iowa corporation (the “Company”), confirms its agreement with Lehman Brothers Inc. (“Lehman Brothers”) and Merrill Lynch & Co. and Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”) and each of the other Underwriters named in Schedule A hereto (collectively, the “Underwriters”, which term shall also include any underwriter substituted as hereinafter provided in Section 10 hereof), for whom Lehman Brothers and Merrill Lynch are acting as representatives (in such capacity, the “Representatives”), with respect to the issue and sale by the Company and the purchase by the Underwriters, acting severally and not jointly, of the respective principal amounts set forth on Schedule A of $100,000,000 aggregate principal amount of the Company’s 6.30% Senior Debentures due 2034 (the “Securities”). The Securities will be issued pursuant to an indenture dated as of August 20, 2003 (the “Indenture”) between the Company and J.P. Morgan Trust Compa
