There are several theories about this SU. It seems most likely that this rubble layer was associated with later spoliation activity. However, another theory is that this SU was part of a leveling layer for a later floor. Note (2018-06-26): While excavating this SU, it became apparent that there were very high concentrations of mortar that cemented the rubble particularly along the northwestern corner, center area of the eastern wall, and the southeastern corner of room I-10. We decided to include these dense mortar sections in this SU, since the material and composition were the same. We photographed these dense mortar and stone areas and drew a second sketch to show these areas before removing them. Also, while pickaxing, we noticed a small echo that may indicate a cavity under the northern area of room I-18.