A detailed magnetic gradiometer survey was conducted to inform proposed residential development on land at Sunnydale Close, Surfleet. The survey recorded a number of magnetic anomalies that were thought to represent the remains of a former watercourse and a recent boundary or ditch, along with a more amorphous feature towards the north-eastern corner of the site. {1}{2} Subsequent trial trenching in this area confirmed the presence of a former watercourse running across much of the site, and resolved the recent boundary or ditch anomaly as the route of an electric cable. The trenching also resolved the amorphous feature as a spread of dumped medieval saltmaking waste, with other likely associated pit features in close proximity that had not been identified by the geophysical survey (see ELI12888).