Site 335 - Geophysics Survey Report Heritage Non-intrusive Survey Reports Group 024

The survey was undertaken using four Bartington Grad601 sensors mounted at 1m intervals (1m traverse interval) onto a rigid carrying frame. The system was programmed to take readings at a frequency of 10Hz (allowing for a 10-15cm sample interval) on roaming traverses (swaths) 4m apart. These readings were stored on an external weatherproof laptop and later downloaded for processing and interpretation. The system was linked to a Trimble R8s Real Time Kinetic (RTK) differential Global Positioning System (dGPS) outputting in NMEA mode to ensure a high positional accuracy for each data point, in accordance with EAC guidelines (EAC 2016). All suitable areas within the Site were surveyed and no anomalies of clear archaeological potential have been identified. The Site is largely covered by a dense spread of magnetic disturbance likely caused by magnetic debris used to try and improve drainage on the site. This interpretation is supported by evidence of brick/rubble and other debris on the ground identified by the survey team. Given the strength of magnetic response it remains plausible responses from more weakly magnetic archaeological features could be masked if present in this area. The only finding of note is a curvilinear anomaly of uncertain origin recorded at the southern boundary of the Site which is also the present field boundary. A modern service/drain remains the most likely cause of this feature however an archaeological cause cannot be ruled out based on the geophysics data alone. Elsewhere a service pipe extending from the site boundary and farm to the west, towards the pond within the Site and two faint linear trends likely agricultural in origin are the only other identifiable anomalies in the survey data.