APPENDIX A_CH09.0088.GE Building 42 Phase III.Salisbury.GeoRpt.pdf

This is a geotechnical engineering report documenting subsurface exploration findings for Building 42 Additions & Renovations Phase III at the W.G. Hefner Veterans Affairs Medical Center in Salisbury, North Carolina. The report was prepared by Geoscience Group, Inc. for RPA Design, P.C., dated October 18, 2011, under Geoscience Project No. CH09.0088.GE.

The subsurface exploration comprised four soil test borings (B-1 through B-4) advanced to approximately 15 feet below ground surface and one hand auger boring (HA-1) extended to approximately 10 feet below ground surface. Standard Penetration Tests and Dynamic Cone Penetrometer tests were performed to evaluate soil strength and density. Findings indicate existing fill materials consisting of sandy SILT and silty CLAY soils to depths of 3 to 6.5 feet, underlain by residual very clayey SILT soils. Penetration test results ranged from 3 to 23 blows per increment. No measurable groundwater was observed during boring activities. The report recommends that existing fill be removed and replaced with properly compacted structural fill for foundation support, with two alternative site development options presented: complete removal with undercutting, or selective undercutting with compaction and bridging of existing fill. Design recommendations specify a net allowable bearing pressure of 3,000 PSF for shallow foundations, minimum footing dimensions of 16 by 24 inches, and a Site Class C classification for seismic design. Temporary slopes require inclinations of at least 1¼(H):1(V), and all excavations must comply with OSHA regulations. The report includes generalized subsurface profiles and detailed test boring records in the appendix.