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5.3 PHYSICAL. Sf=TtTNG SOURCES Topographv: The 1993 United States Geological Survey (USGS) Midland, NC 7.5-minute series quadrangle was reviewed to examine the topography and drainage of the subject site and vicinity. A 2005 Cabarrus County GIS contour map was reviewed and compared to the USGS quadrangle. The maps indicate that the highest elevation is located in fhe southwest portion and on a knoll in the northwest portion of parcel number 5544636383 at 535 feet MSI_. The site slopes moderately downward to the northeast and southeast to a low elevation of 480 feet MSL. Drawing 2 represents a portion of the USGS quadrangle that was reviewed. The 2005 Cabarrus County GIS contour map is included as Drawing 3. Both drawings are incorporated in Appendix A. Surface and Groundwater Flow Directions: Surface water flow is by sheet drainage and is governed by the ground contours. The general surface water flaw is likely taward Muddy Creek. Groundwater flow was not determined as part of this assessment. Groundwater flow directions in the Piedmont are controlled by morphology with flow occurring perpendicular to the contours from high to low elevations. We expect the general groundwater flow direc#ion to be toward Muddy Creek. According to FEMA Flood Panel numbers 3710554300 J and 3710554400 J, the majority of the subject site encompasses land located inside Zone "X" {areas determined to be outside fhe 0.2% annual chance floodplain). Areas around Muddy Creek and the former quarry area are located inside Zane "AE" (Special flood hazard areas subject to inundation by the 1°!o annual chance flood event. The base flood elevations are determined.) The FEMA Effective Date of the map is May 25, 2007 (Preliminary). Surficial Geology: Based on a review of the Soil Survey of Cabarrus County, North Carolina and the I National Cooperative Soil Survey of the Natural Resources Conservation Service, the majority of fhe soil J on fhe subject site is in the Badin series. These soils are well drained and are located on undulating upland ridges that are highly dissected by intermittent drainageways. The surface layer is brown channery sift loam. The subsoil is comprised of yellowish red channery silty clay loam to red silty clay to mottled yellowish red and strong brown channery silty clay loam. The underlying material is moderately hard, highly fractured slate. Unweathered bedrock can be found at a depth of 40 inches. If left unprotected, runoff is rapid and erosion is a moderate hazard. The flat slate fragments in the surface layer help hold wa#er and reduce erosion. The shrink-swell potential and permeability are moderate. Chewacla sandy loam, located along the south side of Muddy Creek, is somewhat poorly drained and is found on broad and flat floodplains along major streams and long, narrow, and flat floodplains along minor creeks and drainageways. This soil has moderate permeability and the available wafer capacity is high. It is subject to frequent flooding for brief periods from November through April of most years. The surface layer is typically dark brown sandy loam. The subsoil consists of yellowish brown loam to mottled grayish brown and dark yellowish brown loam to grayish brown sandy clay loam. The underlying material is gray mixed fine sand and loamy sand. 1 Goldston very channery silt loam is located in the southwest portion of the subject site. !t is well drained to excessively drained and is located on rolling side slopes, knolls, and narrow ridge crests throughout the slate belt of Cabarrus County. The landscape is typica]{y uneven and highly dissected by intermittent drainageways. The surface layer is characteristically brown very channery silt loam. The subsoil is made up of pa#e yellow very channery silt foam. The underlying material is mixed slate fragments and silt Wallace Property Ph 1 ESA CESI Protect No. 080913.000 October 14, 2008 Page 13 Attachment number 1 G-9 Page 505 of 627