Geophysical Survey, Evaluation at Proposed Energy STorage System, Indian Queens Substation, St. Enoder, Cornwall

The geophysical (gradiometer) survey was undertaken in accordance with current best practice and CIfA guidance; and follows the guidance outlined in Geophysical Survey in Archaeological Field Evaluation (English Heritage 2008); Standard and Guidance for Archaeological Geophysical Survey (CIfA 2014 updated 2020); EAC Guidelines for the use of geophysics in Archaeology: Questions to Ask and Points to Consider (Europae Archaeologiae Consilium/European Archaeological Council 2016). 'Archaeological geophysical survey uses non-intrusive and non-destructive techniques to determine the presence or absence of anomalies likely to be caused by archaeological features, structures or deposits, as far as reasonably possible, within a specified area or site on land, in the inter-tidal zone or underwater. Geophysical survey determines the presence of anomalies of archaeological potential through measurement of one or more physical properties of the subsurface.' (Standard and Guidance for Archaeological Geophysical Survey 2014). The results of the survey will, as far as possible, inform on the presence or absence, character, extent and in some cases, apparent relative phasing of buried archaeology to inform a strategy to mitigate any threat to the archaeological resource. The survey identified four groups of anomalies across the field. These were predominantly linear ditch boundary features associated phases of the existing and historic field-system and probable drainage features. Possible pits and/or tree-throws as well as possible mining activity alongside anomalies associated with agricultural activity, metallic debris and ground disturbance were also apparent. The degree of preservation of the identified features appears to be poor. The majority of the anomaly responses are weak, with some intermittent and barely discernible from the background geology. This suggests that many of the identified features only survive to a shallow depth, their intermittent nature suggesting only partial survival. However, it is possible that additional, even more ephemeral features, are masked by the background geology and modern disturbances. The results of the geophysical survey would suggest that the archaeological potential for the site is low. The majority of the identified features relate to land drainage, and whilst the presence of the Medieval farmstead to the north-east and Prehistoric or Romano-British activity in the wider landscape mean that the presence of features of either period cannot be ruled out, the results of the geophysical survey and extent of disturbance would suggest that these are unlikely to survive. Any development of the site is likely to encounter and destroy the buried archaeological resource (should it be present), and whilst further mitigation through targeted evaluation trenching may validate and clarify the results of the geophysical survey, it appears unlikely that any remains (if present) would be of any significance.