AutoCAD Civil 3D :: Create A Subgrade Surface For Landfill Project

I need to create a subgrade surface for a landfill project.  I have already created profiles and sections on a 200x200 ft grid along a baseline alignment that follows the center of the proposed landfill.  In my profiles and section views I have drafted in my proposed subgrade elevations.

Is there any way to create a surface by selecting critical points along the profiles & sections?  I would prefer not to use a grading group b/c the site is in excess of 200 Acres, and the grading tools tend to crash Civil 3D 2009 on large sites.