verification of ORD earthwork

Does anyone know of a way to verify the numbers we're getting for earthwork?  Either by EAV or prismoidal?  I have lobbed the question out here before, but the only way I know to check is to check the drawing cross section model and use the 'flood' option to measure an area, while making sure it is flattened to view.  I can't seem to get that to work on half of my closed areas either.  

There must be an easier way to justify the calculations, surely?

Any ideas are very welcome!!

Thanks,

Katie Wade