York Historic Environment Record

The change of use to the building did not require any significant groundworks to be undertaken beneath the existing basement floor. Groundworks were initially limited to the two investigative boreholes, which were archaeological monitored. Following a review of the results of the boreholes further groundworks were designed to be limited to the insertion of a series of driven steel mini piles to support a proposed lift. As the driven piles would not result in any arisings, agreement was reached with the City Archaeologist that the piling could be undertaken without archaeological monitoring. This report details the deposit sequence recorded in the two geotechnical boreholes. Both boreholes encountered highly organic archaeological deposits immediately below the existing basement floor and its associated sub-base, which were a combined thickness of between 0.50m and 0.55m. Although datable artefacts were rare the organic deposits are likely to be of early medieval date, as indicated by a later 9th to mid 10th century sherd of pottery and the sequence of deposits recorded beneath the basement in 1999. This programme of archaeological monitoring has confirmed the results of previous investigations in this area , that up to 4m of well-preserved organic archaeological deposits are present directly beneath the basement floor of this site. With the exception of the very limited, localised impact caused by the insertion of the driven piles these deposits remain in-situ under the site.