Archaeological mitigation took place intermittently as a watching brief between October and November 2019. The watching brief was maintained while the instalment and clearance of leaf mould from the ditch was removed to ensure that the profile of the ditch and its fills and bank were not impacted. The modern fills were excavated using a fivetonne mechanical excavator with bladed ditching buckets and hand excavation took place when required. Oxford Archaeology was commissioned by Buckingham Group on behalf of St Catherines College to undertake a watching brief during the clearance of leaf mould from a drainage ditch to the south of a possibly Saxon earthen bank. The watching brief set out to ensure that the profile of the ditch remained unaffected by the works. The works were conducted over six days with the clearance being done in sections according to site access. During the clearance, modern infilling consisting of tarram, sand and aggregate was cleared from the southern end of the ditch, and gardening waste from the northern end. A thin layer of leaf mould was cleaned along its full extent onto clean deposits. No archaeology was impacted during the works.