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Wright Environmental September 15, 1997 Page 2 Parcel 5 Plate 2 shows the locations of the pertinent features. Parcel 5 is located south of Parcels 1 and 2, and west of Sacramento Street, between East Weber Avenue and East Main Street. The area of investigation measures approximately 300 feet (north- south) by 150 feet (east-west). This area is bound to the west by a chain-fence and building, and to the east by the limits shown on the site map provided by Wright Environmental. Surface conditions consist of localized areas of concrete, soil, and asphalt. Surface metal objects include pipes exposed at the surface, a billboard to the south, and utility manways. Parcel Prior to our work, Wright Environmental arranged to have the various debris in the northern portion of Parcel 6, moved to the southern portion. We investigated the northern portion of Parcel 6 on August 27. Upon completing the northern portion, all of the debris in the southern portion was moved to the north. We investigated the southern portion on September 2. For ease of presentation, we have combined the data and maps of the northern and southern portions of Parcel 6, and will refer to the work at Parcel 6 as a single investigation. Plate 3 shows the locations of the pertinent features associated with Parcel 6. Parcel 6 is located to the south of Parcel 5, between East Main and East Market Streets. The area of investigation is bound to the north, south, and east by a metal fence, and to the west by the east wall of the building. The only notable surface metal within the area of investigation consists of a 20 foot length of 4" metal plate that is set in concrete and located in the extreme southwestern corner. GEOPHYSICAL EQUIPMENT We used the vertical magnetic gradient (VMG), electromagnetic (EM), ground penetrating radar (GPR), and electromagnetic line location (EMLL) equipment to obtain the necessary geophysical data. Our instrumentation consisted of a Scintrex ENVI- MAG magnetic gradiometer, a Geonics EM-31 DL conductivity meter, a Geophysical Survey Systems Inc. SIR-3 radar system with a 500 MHz antenna, and a Fisher TW-6 Pipe and Cable Locator. The VMG equipment was used measure variations in the vertical gradient of the earth's magnetic field to determine the locations of buried ferrous metal. The EM equipment was used to map variations in the subsurface conductivity that can be caused by variations in subsurface materials. This instrument simultaneously records terrain conductivity (TC) and in-phase (IP) data. Terrain conductivity is the resultant or average electrical conductivity of the