Further study indicated that this large layer was associated with the collapse and abandonment of the Republican house.
Large layer of natural accumulation between the house to the west and bounded on the north, south, and east mostly by bedrock; several rock-cut channels appear to run under this layer (see sketch). The layer covered SU514 and SU515 (the infant burial excavated in 2010) and was partially removed to expose the edges of the cut. There are two notable features in the southeast corner of the SU: a cluster of large tufo and basalt chunks surrounded by pottery and a circular patch of reddish-orange soil that has not been assigned a separate SU yet (excavated in 2011- cut SU581). We excavated SU516 in 2011. The layer covered bedrock to the north and east. On the west we encountered a greater concentration of tufo, basalt and other materials along the line of the east side of the house. Under SU516 on the east we found a more compact, brown layer with crumbling tile and pottery. See also SU583.