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2.5 Hand Cone Penetrometer Probes A series of hand cone penetrometer probes was completed around the perimeter of the building, at the locations shown on Figure 2. These probes were completed by pushing a steel rod with a cone-shaped tip into the ground and measuring the deflection of a proving ring as the probe was advanced. The relative density of the shallow soils was then estimated. In general, very loose to loose soils were encountered around the perimeter of the building to depths of up to 102 inches below grade. The hand cone penetrometer data are summarized in Appendix C. 2.6 Ground Penetrating Radar Survey Ground Penetrating Radar (GPR) survey is a non-invasive geophysical test method that utilizes transmitted (and received) electromagnetic pulses (radar) to evaluate shallow surface soil and geological conditions. GPR measures the electrical properties of the subsurface soil materials and other buried objects and can only identify subsurface features that have a sufficient electrical contrast between the feature and the surrounding materials. The procedures used for testing were in general accordance with industry standards of care and established practices I Standard Guide for Using the Surface Ground Penetrating Radar Method for Subsurface Investigation ASTM D 6432). A site-specific GPR survey of the subject property was conducted in conjunction with the site inspection to aid in characterization of subsurface conditions at the site. The purpose of the survey was to evaluate the lateral continuity, thickness of soil, sediment, or bedrock. The goal was to identify geologic features or cultural conditions that may be of interest in our investigation and aid in the positioning of test borings. Information on settings and equipment used during the survey are included in Appendix B. The locations of the GYR transects are shown on Figure 4. Prints of the digitally recorded GPR profiles are retained in the project file and are available upon request. One reflective event was identified on the GPR profiles. Rl: Characterized by well defined, laterally continuous, undulating horizontal to broad overlapping convex reflections observed on the profiles between approximately 32 and 70 nanoseconds. The reflections correlate with the surface of the clayey soil unit encountered in the hand auger borings. Across the site, shallow chaotic hyperbolic reflections (<30 nanoseconds) were present on the profiles and probably represent areas with tree roots and/or utility lines. No features suggestive of obvious subsurface karst or sinkhole features were zdentified in the GPR survey. No downwarping of reflective layers or areas of deeper signal penetration was identified on the transect profiles. S�;t�s6c��;ce I��esti`�ati�r, BCl P��cject i�!cr. 0; 1�t�i> �li�3lif.?� i�I(�SSG213 I��ilC�l �5�04'i�i1i.,^,.;� iS?CC)i't>t�"<1t�C f'(J;li ��' �'i�elt`1 �`I!). ��.�e._i��L' J>;tl.?� 1