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650 <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 /> ems, '3IT Wells <br /> The USGS study for well yields was based <br /> e upon a county-wide inventory of 649 wells <br /> r that are completed in in nine hydrogeologic <br /> } � k <br /> ' PHL units in Orange County, North Carolina. <br /> t <br /> Estimates of ground-water availability were <br /> based upon the well completion records for <br /> these wells that provide information on the <br /> "F drilled depth, reported yields, and depths to <br /> water levels. <br /> rIMF <br /> Awe ` y HL The USGS study concluded the following: <br /> +f+ .L�- Y + <br /> t "M The typical well in Orange County has an <br /> ProPc°Y ,-r I average depth of 208 feet, an average casing <br /> length of 53.6 feet, a static water level of 26.6 <br /> YF"t feet, a yield of 17.6 gallons per minute, and a <br /> NJF well casing diameter of 6.25 inches. The <br /> saturated thickness of the regolith averages <br /> s 27.0 feet and the yield per foot of total well <br /> a 52 317 MW Jdepth averages 0.119 gallon per minute per <br /> foot. Two areas of the County are more <br /> ° I mM s favorable for high-yield wells—a west- <br /> 5 1°ULUMETEHS southwest to east-northeast trending area in <br /> EXPLANATION <br /> 1HOW T01°BkUWTS the northwestern part of the County, and a <br /> .;,1flc)AAGIIITE ❑ 1MVFIW7ffiOLCANIC.WIC southwest to northeast trending area in the <br /> Q JMIFI MUAIAEQU&FEL$IC E 16MV0 Mf:7AVQ4GN1r,IWWMEDIATE <br /> MINIII)MErAIGNEDUS,NTERFADIAM ■ "LlPWLM southwestern part of the County. Well yields <br /> �(MIMI METAIGNEM.iMIK ❑ rWTMS9ICSEarmwAAYPxKs in Orange County show little correlation with <br /> ;NluEaklETAVOLtlWIC�ICLA511C — —6A�In64uNd3Rr topographic or hydrogeologic setting." <br /> Figure 2. Hydrogeologic Bedrock Units. <br /> 2 <br />