; (ii) environmental mitigation; and (iii) construction contingencies; and (C) capitalized interest necessary to meet market requirements, reasonably required reserve funds, capital issuance expenses, and other carrying costs during construction and deployment. (5) Federal credit instrument The term Federal credit instrument means a secured loan, loan guarantee, or line of credit authorized to be made available under the BIFIA program with respect to a project. (6) Investment-grade rating The term investment-grade rating means a rating of BBB minus, Baa3, bbb minus, BBB (low), or higher assigned by a rating agency to project obligations. (7) Lender The term lender means any non-Federal qualified institutional buyer (as defined in section 230.144A(a) of title 17, Code of Federal Regulations (or any successor regulation), known as Rule 144A(a) of the Securities and Exchange Commission and issued under the Securities Act of 1933 ( 15 U.S.C. 77a et seq.)), including— (A) a qualified retirement plan (as defined in section 4974(c) of the Internal Revenue Code of 1986) that is a qualified institutional buyer; and (B) a governmental plan (as defined in section 414(d) of the Internal Revenue Code of 1986) that is a qualified institutional buyer. (8) Letter of interest The term letter of interest means a letter submitted by a potential applicant prior to an application for credit assistance in a format prescribed by the Assistant Secretary on the website of the BIFIA program that— (A) describes the project and the location, purpose, and cost of the project; (B) outlines the proposed financial plan, including the requested credit assistance and the proposed obligor; (C) provides a status of environmental review