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). The survey has not identified any anomalies of definite or possible archaeological origin. The only identifiable features in the magnetometer data are field drains and large magnetic response caused by an extant borehole marker. Occasional sporadic low magnitude and dipolar 'spike' anomalies have natural and modern causes respectively. The findings of the survey reflect the limited archaeological potential of the general area which is not recorded as within a RAZ and that was identified in the Historic Environment search conducted for the HS2 Environmental Statement and remote sensing survey data which did not identify any features within Site 94.
Matt Berry (2022) studied this question.