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Guilarte Residence-Claim No.354110 HCE Report No. 100091.1 Page No. 5 Ground Penetrating Radar A Ground Penetrating Radar(GPR)survey was con ucted at the site in areas of the yard surrounding the house and within the interior of the residence. GPR uses transmitter/antenna pulled along the ground surface that transinits radio waves into the ground and records si nals reflected back froin soil layers. The reflected signals are recorded in digital format and represent virtual c oss-sections of the subsurface soils. The recorded signals are examined for lateral continuity of the soil stra a. The limits of discontinuities or dramatic changes in continuity are identified on a scaled site plan and d lineated as features of interest. The data interpretations, relative to the possible presence of sinlchole activity are performed by an experienced,professional geologist. The results of the survey and the interpretations of t e data are presented in the final GPR survey report. The coinplete GPR survey report is attached in A ei�dix C of this report. Standard Penetration Test(SPT)Borings The four Standard Penetration Test(SPT)borings we performed in general compliance with ASTM's procedure for standard field penetration tests,D-1586. The bor ngs extended to depths of 58 feet 9 inches,59 feet,73 feet 10 inches, and 79 feet 5 inches. The SPT borings were advanced by means of an all-t rrain vehicle(ATV)-inounted drill rig.The ATV-mounted rig was used to limit damage to the landscaping and o allow easier access to boring locations. The drilling was performed employing wash rotary drilling technique and bentonite drilling fluid to stabilize the boreholes. At periodic intervals,the soil was tested and sampled b ineans of the Standard Penetration Test. The borings were performed in general compliance ith ASTM's procedure for standard field penetration tests, D-1586. After drilling to the sainpling depth and cl aning the borehole,the standard 2-inch outside diameter, split-barrel sampler was seated by driving it 6 inch s into the soils at the bottom of the borehole. Then the sampler was driven an additional 12 inches by a 14 -pound harruner falling 30 inches. The number of blows required to produce the 12 inches of penetration is -ecorded as the penetration resistance N. This N-value is plotted on the left side of the Boring Logs which are attached in Appendi,r D. Fi�zn•es 2 ar�d 3. The SPTs were perfonned continuously to 10 feet a d at 5-foot intervals thereafter to the terminations depths. The upper 4 feet of the SPT borings are generally ad anced by hand auger to prevent dainage to possible buried utilities. The soil sainples were obtained at the deptl s where the SPTs were perforined. The soil sainples were then classified in the field,placed in sealed containe s, and retuined to our laUoratory for further evaluation Uy our project engineer. Auger Borings The auger borings were performed by manually turni g a 3-inch diameter,6-inch long sam�ler into the soil until it was full. The sampler was then retrieved and the s ils in the sampler were visually classified. The procedure was repeated until the desired tennination depth wa achieved. Sainples of representative strata were obtained for fiu-ther visual evaluation and classification in o r laboratory. The Auger Boring Records are attached in Apper7dix D. FiPan•e S of this report. Test Pits i Two test pits were excavated on the rear side near the right rear corner of the residence,and on the front side near the fi-ont right corner of the residence,and the result are presented in the following section of this report. The test pits were hand excavated next to and beneatl� t e exterior walls to obseive and record the type, size, and condition of the foundation.