This report supplements the safety evaluation report (SER), NUREG-0847 (June 1982), Supplement No. 25 (November 2011, Agencywide Documents Access and Management System (ADAMS) Accession No. ML12011A024), with respect to the application filed by the Tennessee Valley Authority (TVA), as applicant and owner, for a license to operate Watts Bar Nuclear Plant (WBN) Unit 2 (Docket No 50-391).