York Historic Environment Record

Archaeological monitoring took place during the mitigation excavation of hydrocarbon contamination hotspot S10, Leeman’s Yard, between December 2022 and the February 2023. Following several stages of excavation, the f inal area mitigated was an irregular rectangle aligned north-west to south-east. At the top, the excavation was c.65m long and up to c.30m wide, though the battered sides resulted in the deepest area being excavated c.5m less on each axis. The depth of the excavation was generally c.4.5m deep, though this varied depending on the adjacent ground levels at the time of the works. Excavations depths were to a depth of c.7m aOD in the f irst excavations ; however, once it was clear that the contamination sat above natural clays, this was reduced to c.8m aOD. Naturally occuring geological deposits were identifed at c.8.10m aOD, overlain by approximately a buried soil c.0.40m thick and then ladscaping associated with railways activity, including track bedding. No archaeological deposits of significance were encountered.