The ARCHIAL Group commissioned Orkney Research Centre for Archaeology (ORCA) on behalf of National Health Services Orkney (NHS Orkney) to undertake a magnetometry survey at the site of Grainbank. The site is located in the vicinity of the Pickaquoy burnt mound and associated traces of settlement (Schedule Ancient Monument No 4346) and of Grain Earth House and Grainbank, a pair of souterrains (SAM No 90154). During a previous walkover survey, a portion of wall was recorded on the site's periphery and was attributed to 19th century agricultural improvement (ORCA 2013). A fluxgate gradiometer survey covering 1.8ha was conducted on the 21th November 2013 in order to identify any potential archaeological features within the survey area to inform on any mitigation strategies that may be required. The geophysical survey has demonstrated the presence of ridge and furrow and the possibility of an associated headland. The rest of the site presents very little magnetic enhancement which can be associated with low potential for the presence of subsurface archaeology. The decision as to the appropriate mitigation response lies with the Local Authority's designated Planning Archaeologist.
Thomas De Salle (Wed,) studied this question.