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38 <br /> � e&MMes <br /> Geology <br /> The bedrock underlying the Property is underlain by metamorphosed volcanic dacitic <br /> lavas and tuffs. These rocks are overlain by a thick layer of regolith that resulted from <br /> the in-place weathering of the parent rocks. The upper part of the regolith comprises <br /> saprolite and soil and typically does not provide significant groundwater to wells. The <br /> bottom of the regolith is referred to as Partially Weathered Rock (PWR) and generally <br /> has a greater permeability than the overlying materials. The bedrock provides water to <br /> wells from interconnected fractures and joints that are intercepted by the well bore. <br /> The hydrogeologic units of the bedrock identified by the USGS report are shown in <br /> Figure 2. The site is contained in the metavolcanic felsic (MVF) unit. <br /> s Wells <br /> The USGS study for well yields was based <br /> upon a county-wide inventory of 649 wells <br /> that are completed in in nine hydrogeologic <br /> PHL units in Orange County, North Carolina. <br /> Estimates of ground-water availability were <br /> based upon the well completion records for <br /> WO r17 these wells that provide information on the <br /> drilled depth, reported yields, and depths to <br /> water levels. <br /> ti <br /> r The USGS study concluded the following: <br /> AN s rs� rHL <br /> 4 WN " The typical well in Orange County has an <br /> UffP«��°Y .� average depth of 208 feet, an average casing <br /> length of 53.6 feet, a static water level of 26.6 <br /> feet, a yield of 17.6 gallons per minute, and a <br /> MV well casing diameter of 6.25 inches. The <br /> saturated thickness of the regolith averages <br /> 27.0 feet and the yield per foot of total well <br /> 5 depth averages 0.119 gallon per minute per <br /> foot. Two areas of the County are more <br /> favorable for high-yield wells—a west- <br /> a 5 1UIMMELE95 southwest to east-northeast trending area in <br /> EXPLAI4ATION <br /> "DFOGEQOMUMM the northwestern part of the County, and a <br /> 0OMIAMMM ® IM MM7AV%rANEC.FUSIC southwest to northeast trending area in the <br /> �.4W KTAJ6NEOU&.FE4MC I)AV0MUAVQLCAVAT� <br /> IC.IHTEAMEOI <br /> MJWI)METAIGNEDUS.lNtEMW[M,;% ❑ IpHLIPWLM southwestern part of the County. Well yields <br /> IMmIMETJ7,IGNEm.MUFK [J rTRPITRAA.SSICSE°IMEIffAAYRDCKS in Orange County show little correlation with <br /> �PMfAIETArOECAIlICE1CtD1911C BA511NflUJ"°AI;Y topographic or hydrogeologic setting." <br /> Figure 2. Hydrogeologic Bedrock Units. <br /> 2 <br />