Much of the former refinery and surrounding area is underlain by historic fill material, which was primarily placed for the purpose of reclaiming lowlands along the banks of the tidal Delaware and Schuylkill Rivers during industrialization. The fill materials are heterogeneous in nature and have been characterized as a mixture of compacted soil and anthropogenic debris, including sand, clay, silt, gravel, cinders, concrete, asphalt, crushed stone, ash, glass, brick fragments, and wood. Apparent fill thickness ranges from a veneer where historic land surfaces were highest to more than 20 feet within the locations of former lowlands such as stream valleys, marshes, and open pits.
Fill may or may not have been encountered in each boring. If fill was encountered and was characterized by the person logging the hole, the boring log would contain the description. Evergreen is not aware of and cannot speculate on all potential sources of historic fill at the site. The general descriptor “fill” is not necessarily indicative of imported materials but of disturbed native soils with man-made debris.