EDO4265 - Southern Dorchester By-pass, soil test pits; watching brief 1986

The excavation of 23 soil test pits for geotechnical soil testing prior to the construction of the Dorchester By-pass was observed by Wessex Archaeology during August and September 1986. The soil pits were spaced around the route of the Dorchester By-pass from Monkey’s Jump in the west to Stinsford in the east. All Test Pits were dug in arable fields. No significant archaeological features were revealed. The majority of the testpits revealed only a thin ploughsoil immediately overlying the natural chalk bedrock, except towards the top of the Bridport Road ridge and at Stinsford, where there were layers of clay and gravel capping the chalk. Nine test pits, mainly to the north of Conygar Hill, had thin layers of reddish-brown clay colluvium beneath the ploughsoil and overlying the chalk bedrock. One Test Pit (T31/1), at the base of the coombe north of Conygar Hill, revealed a small irregular feature of unknown date and function. Another Test Pit (T29/1), at the base of Conygar Hill close to Herringston Road, revealed the edge of a probable swallow hole, the upper part was filled by colluvium and it was cut by a field terrace.