exposed on July 3. Excavation begins on july 3rd by trowel. What we initially thought was a foundation trench, it was realized during excavating was not. The constructors of wall 8122 filled the foundation trench with poured concrete instead of soil and rubble. For this reason, It is not possible to excavate this foundation trench. Likely, the soil around the wall 8122 was Looser owing to water or root activity. This SU has been put as equal to SU 8339.