Two percussion test boreholes was put down at two alternative sites at the Railway Yards, Wolsely, to test the foundation conditions below a proposed silo site. Subsurface conditions at both sites A and B are essentially similar, consisting of a series of Pleistocene to Recent fluviatile clays overlaying Pliocine estuarine sands (Loxton Sands). The test bores at both sites did not encounter the water table. At site A, the clays are of moderate strength, but would be subject to settlement under load. At site B, the clays are of low strength and would be subject to both shear failure and settlement under load.