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Geophysicist, who is also responsible for the interpretation of <br /> the data. <br /> A nominal 10-foot grid was laid out on the pavement and <br /> planters for survey line control in the sidewalk/driveway <br /> survey area . A 5-foot grid was established over a 20--foot <br /> square area in areas of the proposed monitoring wells . The <br /> (0, 0) coordinate for all areas except MW-3 is the intersection <br /> of the curb lines at the corner of Wilson Way and Market Street <br />' (Figure 3) . The (0 , 0) coordinate for MW-3 is shown on Figure 4 . <br /> In accordance with the project specifications three geophysical <br /> instruments were provided for the survey: <br /> t1. Ground penetrating radar (GPR) : Geophysical Survey <br /> Systems, Inc. model SIR--3 with a 120 MHz antenna. <br /> 2 . Electromagnetic profiler (EM) : Fischer Research model <br /> G-3 with separate transmitter and receiver coils. <br /> 3 . Magnetometer : Geometrics model G856 -AX proton <br /> magnetometer. <br />' Continuous GPR and electromagnetic profile data were collected <br /> over the survey area on a 5-foot grid of north/south and <br /> east/west trending lines using the previously described 10-foot <br /> spaced dots as guides . In the vicinity of the proposed <br /> monitoring well sites data were collected on a 2 . 5-foot grid. <br /> Magnetometer data were unstable due to the effects of the bank <br /> building and surrounding metallic cultural features and were <br /> not collected. <br /> The GPR system provides hard copy records in the form of <br /> profiles of distance versus signal reflection time. Changes in <br /> subsurface soils electrical properties caused by buried <br /> objects, changes in soils types, or fluids may be recognized in <br /> the records . GPR data quality was very good and signal <br /> penetration with the 120 MHz antenna varied between 5 and 8 <br /> feet in most areas. However, GPR data could not be collected <br /> in the planter areas because of the high bushes and trees. <br /> The EM profile system provides audio and visual signals over <br /> metallic targets . The location of the targets is manually <br /> recorded. <br /> Results <br /> The interpreted results of the GPR and EM surveys were plotted <br /> on a field drawing as the survey progressed. The data were <br /> reviewed in the office and the final interpretations are <br /> plotted on Figures 2 , 3 , and 4 . The proposed well locations <br /> were painted in white on the pavement . The buried lines <br /> indicated in the figures were painted as dashed, red lines on <br /> 1 <br /> 2 <br />