The foundation runs along the western face of wall 6140 and the western edge of threshold 6171 and was constructed as part of the reorganization that delimited Room 14 on the eastern side. The northern limit is where the foundation meets a large tufo block/slab that appears to have been part of an earlier leveling layer, as it may run under wall 6131. Since walls 6140 and 6131 and threshold 6171 appear to have been constructed in phase, it seems odd that the foundation is only found along the western face of SUs 6140 and 6171. This may indicate that the tufo block/slab formed a barrier to the foundation trench or that the tufo block/slab was incorporated into the foundation for the remainder of threshold 6171 and for wall 6131.