Layer of accumulation, predominately silt with mixed geological and anthropic inclusions, both of a fragmentary nature. The layer appears to continue under wall 4004. Abuts 4006 on the western side. Continues past excavation limit to the east. Underneath the layer we uncovered a layer with fragmentary ceramic and yellow tufo to the north-east. Underneath 4017, a similar layer of sandy silt was uncovered, and it extends throughout the entire room (4018) and covers wall 4007