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C~ • EXHIBIT G Water Information The proposed mining operation is located in the West %2 of Section 29, Township North, Range 67 West in Weld County. The site is located approximately two miles north of Jo stown and 3 miles east of I-25 and is adjacent to the Big Thompson River. The operation will mpact [he Big Thompson River in the form of depletions due to evaporation and operational loss s associated with mining. These impacts, however, aze of minor consequence and can be miti ated without injury to the vested senior rights downstream of the site. The operation will consi t of sand and gravel production. `z The project will crea foy~ open gravel pit lakes with approximate) 20 acres f e posed surface. The reclamation plan will leave unlined lakes that aze hydrau ica y cone cted to the alluvial aquifer. A substitute su 1 Ian for the replacement of stream depletions during the mining phase will be submitted to the State Engineers ice. The operator w~ tam an approved augmentation plan through Colorado Water Court afrer mining is comp) ted. The length for the completion of the project is estimated at 7 years. Water Use Water use at the site will include evaporation from the wash pond, settling pond, watering trenches, and existing exposed surfaces, water retained in material removed from a site and dust control of haul roads and stockpiles. The exposed groundwater associated wi the dewatering trenches is estimated at 1.0 acre. The total exposed acreage during mi ing, including the existing gravel lakes, will b approximately 13 acres. Mining a[ the site will intercept the groundwater table. In order to enable dry mi g, dewatering trenches will be constructed around the perimeter of the pit. This water will be ro ted and pumped into existing gravel lakes and allowed to percolate back into the alluvial a uifer. The NOAA Technical Report NWS 33, (U.S. Department of Commerce) was used to determine gross evaporation. Forth' location, the annual evaporation is 41.0 inches. Monthly evaporation percentages as suggested y the Office of the State Engineer were used to calculate monthly evaporation. Precipitation was estimated using the Colorado Climate Center's Monthly Climati Data for the Windsor Weather Station. Annual precipitation at the site was assumed to be equ to the Windsor station, which is 12.54 inches. Effective precipitation was calculated as 0% of total precipitation. Net evaporation was then computed as the difference between gross evaporation and effective precipitation. The net annual evaporation at the site is 2.7 feet. Thu ,the resulting net annual evaporative consumptive use during mining operations is 34.9 acre-feet The evaporation associated with the post reclamation lakes will be approximately 53.7 cre-feet per year. The post mining augmentation requirements can be seen in Table No. 1. / l2 Amendmen! Page 9 oj23