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GPR Survey Report Mathew/ Aley Rental Property Project No. 03-15564 Page 2 of2 GPR Survey Results: Inspection of the GPR transect profiles indicates the depth of penetration of the radar signal ranged from 14 to 16 feet below grade for the transects completed utilizing the 500 MHz antenna, and from 20 to 23 feet below grade for the transects completed using the 250 MHz antenna. Below these depths the radar signal was attenuated, probably due to saturated and/or clayey soil conditions. The depth estimates are based on an assumed signal travel velocity of 0.45 feet/nanosecond for the dry sandy soils, as encountered in the hand auger borings completed by BCl. On most of the profiles, a series of weak to moderate intensity, continuous, subparallel, horizontal and sinuous reflection events was identified at estimated depths of 7 to 11 feet below the land surface. The reflective horizon may represent the top of a subsurface clayey soil unit (clayey sand to sandy clay). Across the site, 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 west (front) yard area, and probably represent underground utility lines or pipes (Figure 3). Copies of the GPR transect profiles are retained in the project file and are available upon request. One possible subsurface anomaly was identified in the GPR survey (Feature 1), at the location shown on Figure 3. The anomaly is located in the west yard, and lies adjacent to the ground collapse feature below the front porch of the house. The anomaly is characterized by a zone of shallow disorganized reflective patterns and associated deeper signal penetration, and is interpreted to represent a shallow zone of disturbed soils and discontinuity within the underlying subsurface soil layers. 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. It is very important to note that 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 of Citizens Property Insurance Corporation and ROL Insurance Consulting. Any other use of this report or parts of this report shall be authorized in writing by BCl Engineers & Scientists, Inc.