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27 <br /> ea*&MM5 <br /> Geology <br /> The property is underlain by metamorphosed intrusive and volcanic units of the Hyco Formation that are <br /> 615 to 633 million years old' as shown in Figure 2. The western majority of the site is underlain by <br /> mixed epiclastic-pyroclastic rocks with interlayered dacitic lavas (Zhe/pl) and the eastern portion is <br /> underlain by dacitic shallow intrusive of the upper portion of the Hyco Formation(Zhdsi/u). <br /> r• <br /> A <br /> rj 11 � f� M1' �I 5� •"�,- ��. • <br /> Figure 2.--Bedrock Geology. <br /> These rocks contain steeply dipping (near vertical)joints and fractures and are overlain by a regolith of <br /> weathered-in-place materials that comprise partially weathered rock and saprolite. Based upon the <br /> reported depths of surface casings in the two water wells on the property this depth of weathering is 50 <br /> to 65 feet. The upper part of the regolith comprises saprolite and soil and typically does not provide <br /> significant groundwater to wells. The bottom of the regolith is referred to as Partially Weathered Rock <br /> (PWR) and generally has a greater permeability than the overlying materials. The bedrock provides water <br /> to wells from interconnected fractures and joints that are intercepted by the well bore. <br /> Hydrogeology <br /> The hydrogeologic conditions for the property have been generally described in are report by the U.S. <br /> Geological Survey for Orange County'. The hydrogeologic units of the bedrock identified by the USGS <br /> report are shown in Figure 3. The site is contained in the Phyllite (PHL)and Metavolcanic felsic (MVF) <br /> units. <br /> 'Philip J.Bradley,Heather D.Hanna and Randy Bechtel, 2011: Geologic map of the Rougemont 7.5 min Quadrangle, <br /> Orange,Durham and Person Counties,North Carolina. NCGS open-file Report 2011-8. <br /> 3 William L. Cunningham and C.C.Daniel lII,2000. Investigation of Ground-Water Availability and Quality in Orange <br /> County,North Carolina:U.S. Geological Survey Water Resources Investigations Report 2000-4286. <br /> 2 <br />