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EXHIBIT G <br /> Water Information <br /> The proposed mining operation is to be located in Weld County, north of the existing Hall-Irwin, <br /> Tucson gravel pit in Brighton, Colorado. The area to be mined totals to approximately 125 <br /> acres. The southwestern portion of the area will be used for aggregate washing, and concrete and <br /> asphalt production purposes. During the initial phase, a 4-acre area will be mined to serve as a <br /> lined pond to supply water that is required for these processes. Water will be taken from the <br /> Brighton Ditch to fill this pond. Eventually the remaining area, along with the 4-acre pond, will <br /> be utilized for the mining and extraction of sand and gravel. <br /> The total operation will consist of three gravel pit lakes, which will be mined in phases. Lake 1 <br /> will be mined initially, followed by Lakes 2 and 3. Lake 1 will be an open lake. There is <br /> currently an approved substitute supply plan for Lake 1, and a well permit has been issued under <br /> permit number# 47367-F (referred as #95 on Exhibit G-I). A substitute supply plan for Lakes 2 <br /> and 3 will be submitted to the State Engineer's Office. <br /> A slurry wall will be placed around the perimeter of Lakes 2 and 3 to allow for dry mining. The <br /> wall will be constructed before the start of the mining operations on each lake. Upon completion <br /> of the mining operations, the property will be purchased by Central Colorado Water <br /> Conservancy District and converted into a reservoir. The length for the completion of the project <br /> is estimated at 25 years. <br /> Water Use <br /> Water use at the site will include evaporation from the 4-acre pond, water retained in material <br /> removed from the site, dust control of haul roads and stockpiles, and water used in concrete and <br /> asphalt production. <br /> The gross annual evaporation for the site is 38 inches at the subject location, taken from NOAA <br /> Technical Report NWS 33. Evaporation Atlas for the Contiguous 48 United States. The annual <br /> mean precipitation is 15.31 inches. The precipitation at the mine site is estimated to be the same <br /> as that found at the nearest weather station to the site which is located in Denver. The <br /> precipitation was found using data from the publication, Climatographv of the United States No. <br /> 81. <br /> The effective precipitation is computed to determine the net evaporation from the 4-acre pond. <br /> The effective precipitation is calculated as 70 percent of the total precipitation. The net <br /> evaporation is then determined by subtracting the effective precipitation from the gross <br /> evaporation. The net annual evaporation from the pond is 2.27 feet. Thus, the resulting net <br /> annual evaporative consumptive use during the mining operations is 9.09 acre-feet. <br /> G-1 <br />