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Exhibit G -Wales Groundwater and Water Wells Both Worthing Pit and the Expansion Area are located in the alluvial plain of the South Platte River. Groundwater occurs in the alluvial and sand deposits that underlie the South Platte River Valley. Alluvium in the vicinity of the mine site consists of mixtures of unconsolidated gravel, sand, silt, and clay or silty clay. Groundwater in the sands and gravels flows from the southeast to the northwest towards the South Platte River. Deep wells in the area withdraw water from several underlying aquifers, including the Lower Arapahoe and the Laramie-Fox Hills aquifers. The deeper wells in the vicinity of the mine site range from 350 to 1,150 feet below the land surface and are generally used for domestic water. Shallow wells in the vicinity of the proposed Expansion Area withdraw water from the surficial aquifer of the South Platte River. Shallow wells in the area are generally between 20 and 40 feet below the land surface and primarily used for irrigation. A search of the Colorado Division of Water Resources well records was performed to determine the locations of shallow wells within the vicinity of the Expansion Area. The approximate locations of shallow wells within 600 feet of the Expansion Area are shown on Exhibit G-1 and listed in Table G-1. The shallow wells in the area are primazily used for irrigation and domestic uses. Per the TR-2 request, dated November 1, 2000, no surface water wells would be impacted by dewatering of Worthing Pit. In 2000 there were three surface wells within 600 feet of Worthing Pit; however, these wells have now been plugged and abandoned. Should a liner be constructed to isolate the WSF from groundwater, the liner will ensure minimal infiltration of groundwater. Therefore, impacts to local groundwater wells will be negligible. Drawdown of water levels during dewatering of the Expansion Area North could potentially affect shallow wells within 600 feet to the south, east, and north of the mined area. However, there are no active shallow water wells and within 600 feet of the Expansion Area North as shown on Exhibit G-1. There are three shallow water wells within 600 feet of the Expansion Area South. Dewatering at the Expansion Areas will be short-term for two to three years. The applicant (Albert Frei & Sons, Inc.) owns the properties within one-half mile north and south of the Expansion Area North. The property to the northeast of the Expansion Area has a deep well for domestic use. The slurry wall east of the Expansion Area at the Brannan Sand and Gravel Company Pit 29 would mitigate potential effects to wells east of Brighton Road. The South Platte River would mitigate any potential effects to wells west of the Expansion Area. A temporary substitute supply plan is being prepared and will be submitted for approval to the State Engineer's Office. During mining, the temporary substitute supply plan will replace groundwater depletions for the proposed mining operations. The temporary substitute supply plan includes a grave] pit well permit. As part of the permitting process, the State Engineer's Office will assess the potential impacts of the proposed project to all wells within 600 feet of the gravel pit. The applicant will comply with all the conditions and requirements of the gravel pit well permit and will make every effort to mitigate impacts to neighboring wells. 1898-Frei 112 Exhibits_(4.20.05).doc G-5