After further study, it appears that this is the fill of one of a series of small circular holes in the bedrock possibly associated with quarry machinery in the form of cranes or other lifting mechanism. Given the limited ceramic content of the fill, their tentative association with this phase of activity is based on their location, size, and arrangement, rather than their stratigraphic relationships to other features or their finds.

Fill of a posthole, with large pottery and tufo inclusions placed around edges to support a post. Probable association with numerous postholes in the area (near cistern SU 1153), though no pattern is immediately recognizable.