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GPR Survey Results: Inspection of the GPR transect profiles indicates the depth of penetration of the radar signal ranged from 11 to 13 feet below grade for the transects completed utilizing the 250 MHz antenna. Below these depths the radar signal was attenuated, probably due to clayey and/or saturated soil conditions. The depth estimates are based on an assumed signal travel velocity of 0.33 to 0.45 feet/nanosecond for the dry sandy and clayey soils, as encountered in the hand auger borings completed by BCI. On many of the profiles, a series of moderate intensity, continuous, parallel to subparallel, horizontal, and sinuous reflection events was identified between estimated depths of 1 and 5 feet below the ground surface. The reflections are interpreted to represent shallow soil layering within the surficial sandy soils. On most of the profiles, a moderate to strong intensity, continuous, generally horizontal, and sinuous reflective horizon was identified between estimated depths of 5 and 8 feet below the ground surface. The reflective horizon correlates with the upper surface of a clayey subsurface soil layer encountered in the hand auger borings. Shallow hyperbolic reflectors (< 3 feet) were present on many of the transect profiles and probably represent areas with shallow pipes, tree roots, and/or utility lines (Figure 3). Multiple series of prominent hyperbolic reflections were identified in the east and west yard areas, and likely represent underground utility lines or pipes (Figure 3). Copies of the GPR transect profiles are included in this report. No anomalies suggestive of obvious subsurface karst or sinkhole features were identified in the GPR survey. No downwarping of reflective layers or areas of deeper signal penetration were identified on the profiles. Limitations: The professional services described in this report were performed using the degree of care and skill ordinarily exercised, under similar conditions, by reputable consulting geologists and engineers practicing in this or similar localities. Ground Penetrating Radar (GPR) is a non - destructive geophysical test method that utilizes transmitted (and received) radio pulses (radar) to evaluate shallow surface soil and geological conditions. GPR measures the electrical properties of the subsurface soil materials and other subsurface objects. As with all geophysical methods, GPR does not provide a positive identification of the type, depth, or character of the subsurface. Additional ground truthing, through soil boring, test pits, or other methods, is required to fully evaluate the subsurface geological and geotechnical conditions. This report and information contained herein was prepared for the exclusive and specific use Security First Insurance/Premier Adjusting Services. Any other use of this report or parts of this report shall be authorized in writing by BCI Engineers & Scientists, Inc. Subsidence Investigation BCI Project No.: 19 -17094 Barker Residence March 2009 Claim No.: 3428 Page 2