Simple 3D surface creation on Civil 3D

Description

Hi,I have a DWG file for small fish pond 20 m x 10 m with 19 contour lines (all are polylines). I need this one converted to surface by some one using Civil 3D. Also I need one horizontal surface added at one of the contour lines. I think this is a maximum one hour work for someone familiar with Civil 3D.I will send the DWG to the suitable person.