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Exhibit G <br /> Page 5 <br /> (b) Identify all known aquifers. <br /> Regionally,two principal aquifers exist in the vicinity of the Permit Area,the Laramie-Fox Hill Aquifer and <br /> the Dakota-Cheyene Aquifer,and one local aquifer system,the Fort Hays-Codell Aquifer.The Laramie-Fox <br /> Hills Aquifer occurs in the basal sandstone units of the Cretaceous Laramie Formation and the upper sandstone <br /> and siltstone of the underlying Cretaceous Fox Hills Sandstone. This aquifer averages 200 to 300 feet in <br /> thickness and consists of relatively thin siltstone and sandstone units interlayered with shale in the lower parts <br /> of the aquifer and one or more sandstone units 40 to 100 feet thick near the top of the aquifer(Robson and <br /> Banta, 1987). <br /> The first encountered economic aquifer beneath the Permit Area is the Laramie-Fox Hills Aquifer. The base of <br /> the Laramie-Fox Hills Aquifer in the vicinity of the Kersey Mine Permit Area is approximately 4,420 ft-amsl <br /> and the Fox-Hills Sandstone is an approximate 150 to 200-feet thick lithology comprised of fine-to medium- <br /> grained sandstone and siltstone deposits interbedded with shale and claystone(Robson and Banta, 1987). <br /> Records indicate that the static groundwater level is approximately 30 ft-bgs near the southeastern section of <br /> the Permit Area and increases to greater than 100 ft-bgs in the northwest section of the Permit Area(CO DWR, <br /> 2023). Comparatively,the anticipated maximum mining depth at the Kersey Mine will be less than 50-ft. <br /> (nominally,in the range of 20-ft.to 30-ft. depth, subject to variation/undulation in topography and <br /> economically mineable limits as may be dictated by sand presence and/or quality characteristics). All mining <br /> will be carried out within the unconsolidated surficial(eolian)sand zone.As indicated in Item(1)above,there <br /> is the potential for mining activity to encounter saturated zones and/or groundwater(to the extent present), <br /> near the southern Permit Area boundary. <br /> With respect to the regional and localized geology,CSC notes that the Site is located in the Denver Julesburg <br /> Basin(D-J Basin).The D-J Basin is a tectonic basin that is located in northeast Colorado,southeast Wyoming, <br /> and southwest Nebraska.The D-J Basin is bounded on the west by the Colorado Front Range(Dechesne,M. et <br /> al.,2011).Areas of the D-J Basin that are adjacent to the Rocky Mountain Front Range have been divided into <br /> two sub-basins.The southern sub-basin is the Denver Basin and the northern sub-basin is the Cheyenne Basin. <br /> The Denver and Cheyenne Basins are defined by the extent of the Laramie Formation and are separated by a <br /> structural feature called the Greeley Arch(Kirkham and Ladwig, 1979). <br /> The Fox Hills Sandstone is 150 to 200 feet thick and is comprised of fine-to medium-grained,olive-brown to <br /> orange-tan,poorly consolidated sandstone and siltstone deposited with shale and claystone in a marine deltaic <br /> or barrier-bar environment. The Fox Hills Sandstone conformably overlies the Pierre Shale and has a difficult- <br /> to-recognize transitional zone. The lower part of the Fox Hills Sandstone typically consists of relatively soft, <br /> sandy shale interbedded with thin,upward-coarsening layers of fossiliferous and concretionary sandstone. The <br /> upper 50 feet commonly consists of medium-bedded to massive,soft to hard sandstone interbedded with layers <br /> of shale(Robson and Banta, 1987). <br /> The Laramie Formation lies conformably above the Fox Hill Sandstone and has a genesis associated with an <br /> alluvial and deltaic continental deposit consisting of two members,a predominately sandstone member(lower) <br /> and a predominantly shale and claystone member(upper). The lower member is generally 100 to 200 feet thick <br /> and consists of tan to light,yellow-gray to white,relatively clean,fine-to medium-grained sandstone <br /> interbedded with lignitic shale and coal. The upper member of the Laramie Formation consists of 300 to 900 <br /> feet thick interlayered fresh-to brackish-water shale and siltstone,lignitic shale,coal seams,and thin, <br /> lenticular beds of fine-to medium-grained 400-foot grained sandstone. This part of the Laramie Formation is <br /> commonly about 300 to 400 feet thick in the central D-J Basin and thickens to approximately 8,900 feet thick <br /> in the northern Denver Basin near Greeley. The sandstone sequence overlying the Laramie Formation has been <br /> Colorado Sand Company II,LLC <br /> Kersey Mine Construction Material Regular(112)Operation Reclamation Permit Application <br /> June 7,2024 <br />