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Paul Madson and Associates, Ltd. . Project BABX-92-813 January 6, 1993 Page 2 B. Results B.1 Logs Log of Boring sheets indicating the depths and identifications of the various soil strata, penetration resistances and groundwater observations are attached. The strata changes were inferred from the changes in the penetration test samples and auger cuttings. It should be noted that the depths shown as changes between the strata are only approximate. The changes are likely transitions and the depths of the changes vary between the borings. � Geologic origins presented for each stratum on the Log of Boring sheets are based on the soil types, blows per foot, and available common knowledge of the depositional history of the site. Because of the complex glacial and post-glacial depositional environments, geologic origins are frequently difficult to ascertain. A detailed investigation of the geologic history of the site was not performed. B.2 Soils The soils encountered in the borings generally consisted of a thin layer of clayey topsoil overlying glacially deposited sands, gravel and clay to the termination depth of the borings. 'The soil types encountered consisted of silty sand, silty clayey sand, clayey gravel and sandy lean clay. The recorded penetration resistances in the sands ranged from 12 to 24 blows per foot (BPF), indicating these soils to be in a medium dense condition. The recorded penetration resistance in the clayey gravel layer in Boring ST-2 was 100 blows for 2 inches. This high blow count is likely due to the presence of cobbles within this layer. The recorded penetration resistances in the sandy lean clay ranged from 14 to 15 BPF, indicating these soils to be stiff in consistency. B.3 Groundwater Groundwater was not observed by our crew in any of the borings during the drilling operation or after the hollow-stem auger had reached the termination depth of the borings. After the auger had been withdrawn from the bore holes, groundwater again was not observeci in any or the borings to cave-in depths ranging from 16 1/2 to 18 feet.