In this paper, we apply a version of the Fast Multipole Method (FMM) to reduce the storage and computation requirement of the boundary integral in the finite element-boundary integral method. By virtue of its O(N1.5) operation count, the application of the single-stage FMM, results in substantial speed-up of the boundary integral portion of the code, independent of the shape of the BI contour. We will discuss the efficiency of the method and present the application of this technique to the computation of electromagnetic scattering from large grooves recessed in a ground plane.
