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® <br /> Geomatrix Consultants <br /> October 14,2003 <br /> Page 2 <br /> and dense brush/tree covered regions. There is also an above ground water tank and a water well <br /> in this area. The water tank appears to be in use by several buildings/trailer residences to the west <br /> of the.survey area. Continuing to the south, an open, gravel-covered region in the south-central <br /> portion of the survey area is relatively free of above ground features. Debris piles exist to the east <br /> and west of this area. To the south are several areas of stored cars, boats, trailers and storage <br /> containers. In the southeast comer of the survey area,we also noted several large debris areas,soil <br /> piles, trucks,trailers, and storage containers. There appears to be active dumping and removal of <br /> debris from the premises that may lead to significantly different future site conditions than those <br /> encountered during the time of our field survey and presented on Plate 1. <br /> GEOPHYSICAL APPROACH <br /> Due to the variable site conditions and access,we performed the geophysical investigation using <br /> three geophysical methods: electromagnetic terrain conductivity(TC),electromagnetic line locating <br /> (EMLL), and electromagnetic metal detection (AM). The TC method was used to delineate <br /> variations in the electrical conductivity of the shallow subsurface..These variations maybe caused <br /> by a variety of sources,including utilities,changes in subsurface materials,as well as large areas of <br /> buried objects. For the purpose of this survey,the focus was on determining the variations caused <br /> by underground utilities. The EMLL and MD methods were used to search for detectable.milities <br /> as well as shallow metal debris that may or may not have been indicated by the TC data. Detailed <br /> descriptions of these geophysical methods including the associated instrumentation and limitations <br /> can be found in Appendix A. <br /> DATA ACQUISITION <br /> Horizontal Control <br /> Prior to data acquisition, we established a horizontal control survey grid over the site using a <br /> fiberglass measuring tape. The survey grid was based on a rectangular coordinate system. Grid <br /> points were marked on the ground surface with pink spray paint and stakes placed on 100-foot <br /> centers(labeled withrespective coordinates). These stakes maybe used for future location reference. <br /> The grid axes are shown on the Terrain Conductivity Contour Map (Plate 2). We established a 0 <br /> Northing axis as the east-west trending fence-line at the southern boundary of the survey area. A 0 <br /> Easting axis was established approximately 50 feet west of the westemmost building foundation. <br /> Survey Coverage and Procedures <br /> In general,we surveyed the accessible portions of the site within the limits of the investigation area <br /> shown by the perimeter dashed line on Plate 1. This area included those portions of the site free <br /> from above ground debris and dense brush cover, and where the geophysical equipment could be <br /> reasonably carried and relatively unaffected by adjacent above ground debris.We collected TC data <br />