here is a etching of the building. it is a classic train depot style building. Thanks for the help BigH.http://files.engineering.com/getfile.aspx?folder=7533532f-714b-4516-a422-e8dc2496ffb2&file=cullpepper.pdf
I have been testing a site with about 10' of mixed fill. Mostly a clay loam and loam mix. below the fill is about 2 feet of original topsoil (river flood plan) before reaching the inorganic alluvium. Total depth to the stiff alluvium is 14'. Does over-excavation sound like the best...