Declares that: (1) the 2.5% interest rate used in the 2006 Revised Supplemental Environmental Impact Statement 2 recommending construction of the closure of the gap in the mainline levee system for the Mississippi River and Tributaries project located at the south end of the New Madrid floodway and considered in the authorization for the closure is the appropriate interest rate; and (2) construction of the closure is a non-separable and integral element of the project.