Locus 28 is a dark brown highly compacted and clay dense soil present in the section under the plaster floor surface of Locus 27. Like Locus 27, it lies between a northern and middle column base and directly abuts the middle column base. It is 0.08 meters west of the 179 E line and roughly 0.5 meters north of the 71 S line. The locus is 2 meters long and one meter wide, and roughly 0.25 meters in depth.

The soil has inclusions of carbon, rocks, and roots. Small amounts of bone, coarsewares, and finewares including bucchero are included in the layer. The locus yielded more bucchero and fine impasto than any other locus in T26 in 2023. One fine impasto body fragment with two inscribed letters was found, as well as a fine impasto fragment with a net pattern in the interior (PC20230042, PC20230043). A fragment of Greek painted imported pottery was also recovered (PC20230024), as well as another possibly imported painted rim (Small Find #17). Along with the large yields of fineware, two diagnostic bones were revealed (PC20230032 and PC20230031). As they were found beneath the plaster floor, the ceramic finds recovered from the locus offer a clear stratigraphic sequence and predate the construction of the building.

The color, compaction, and composition of the locus indicate that it may have functioned as a leveling course for the construction of the OC2/Workshop’s plaster floor. In the process of excavating and leveling Locus 28, a layer of dark reddish-brown soil was revealed in the southern extent of the locus. This layer was declared Locus 32.