York Archaeological Trust
The small percentage of the proposed development which has been evaluated has been extremely useful in determining the quality of the surviving archaeology in the area. It has proved possible, in a limited way, to define four zones of archaeological survival within the proposed development. Zone one includes the trenches contained in Groups 2, 3, 4 and 7 of the evaluation. In this area, archaeological deposits are generally shallow and of such importance that development is likely to disturb significant archaeological remains even if confined to within 1.5m of the surface. Zone two contains the evaluation trenches placed in Groups 6 and 8 together with the Carmelite Street evaluation trenches carried out in 1991 (Hunter-Mann 1991). In this area foundations would probably not disturb significant archaeological deposits within a 1.5m depth limit although waterlogged deposits are clearly present at greater depth and would be affected by sub-surface piling. Zone three contains the evaluation trenches placed in Group 5. In this area industrial deposits of 18th to 20th century date will be encountered at c.0.5m below the present ground surface in most places. These types of deposits have not been regarded highly in the past but they may be of significance to studies in the field of industrial history, particularly that of the gas industry. Other significant archaeological deposits would not be disturbed within a 1.5m depth limit but waterlogged deposits are once again likely at greater depth. Zone four is based on the results from Trench 1, which formed Group 1. The results here were totally unexpected as burials had been found close by in the past. Although none were found on this occasion, it would be advisable to investigate this area further to determine whether the disturbance found in Trench 1 is widespread or not.
Obviously only a small percentage of the development area has been evaluated and in some of the zones, especially zones two and four, archaeology may be discovered at higher levels than noted here, particularly close to The Stonebow and Hungate. The full extent of the church and graveyard of Saint John in the Marsh and the graveyard of All Saint's, Peasholme are currently unknown. Further evaluation trenches would allow more precise definition of the area concerned but these would have to await the demolition of buildings on the site. Any disturbance to the church or burials would be covered by the terms of the Burial Act of 1857 and the Disused Burial Grounds (Amendment) Act of 1981 and would probably require full archaeological excavation.
A single wall which may be part of the Carmelite Friary was identified during the evaluation. It is likely that other remains are present but these appear most likely to be either beneath the street of The Stonebow or immediately to the south of this between Garden Place and Hungate. Investigation in this area would prove difficult at present.
The effects of piling on deep waterlogged urban archaeological deposits are not well understood at present. Deposits of this type are likely to be encountered in zones 2 and 3 and possibly at greater depths than evaluated in parts of zone 1. There is a possibility that the physical disruption caused by piling may lead to changes in the hyrdological regime beneath the ground surface and alter the chemical balance within waterlogged deposits. This site would appear to present a useful test-bed within which to monitor the soil conditions before, during and after development.