Further study indicates that this rubble fill of SU1113 may represent a failed attempt to probe for further quarry sources (since to the North in Area A, the bedrock crops up much higher and closer to the topsoil than in this southern section). It may also simply be evidence of a later shoring up of packing of wall 1058.
Granular silt mixed with smaller fragments of tufo, fill within ditch SU 1113