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Ms. Jamie Gaboriau . • Apri117, 2002 Page 2 ojl ALLUVIUM CHARACTERISTICS The site is located approximately 300 feet from the east bank of the South Platte River. Information obtained from the Colorado Ground Water Circular No. 111 indicates that the transmissivity for this area ranges between 80,000 and 150,000 gpd/ft based on area well characteristics. This information generally indicates that the ability of the alluvial aquifer to transmit water is fairly good. Additionally, information prepared by the USGS found in Hydroiogic Investigations Atlas HA- 746CZ, was also reviewed. This information indicates that ground water flow in the immediate area is generally northward along the Platte River and from the east in a northwest direction . towards the Platte River. The source of ground water for wells located east of the pit would primarily come from the east, not the Platte River or the pit. Furthermore, the depth to the ground water table in the immediate vicinity of the pit for the most part ranges between 20 and 40 feet. The saturated thickness of the alluvial aquifer generally ranges between 20 and 40 feet. However, some azeas were noted as having a saturated thickness of less than 20 feet; a well may be 40 feet deep, but may only have 20 feet or less of water producing aquifer available. Water level declines were noted by the USGS that may range from 5 to 15 feet during dry years, such as what is being experienced now. Under these conditions, declines in the aquifer of 15 feet with only a saturated thickness of 20 feet would likely cause a reduction in well production. The Office of the State Engineer publishes the State's Surface Water Supply Index (SWSI) which is an indicator of water supply conditions in the major river basins. For the South Platte River basin, the SWSI value as of March 1, 2002 is -Z, which indicates that the azea is experiencing a moderate drought. AREA WELLS From preliminary review of the Application for a Mining Use by Special Review Permit prepared for C&M Companies in November 1989, several wells were noted located in azeas adjacent to the site. With exception to the Central Colorado Water Conservancy District (Central), objections were not received from any of the area landowners regarding the issuance of the gravel pit well permit by the State Engineer's Office. An agreement regazding potential impacts to Central's wells was executed on February 9, 2001. The gravel pit well permit for the site was issued by the State on Apri19, 2001. Recently, Aggregate has been contacted by adjacent landowners regarding potential impacts to their wells from Aggregate's dewatering operations at the site. In particulaz, Mr. Steve Brancucci has indicated that several of his wells have been impacted. Mr. Brancucci's wells are located between Weld County Roads 4 and 6, just west of Weld County Road 27. These wells are approximately 2,000 to 2,500 feet from the east property boundary of the pit. Aggregate has also received complaints from a landowner north of the pit site. This well is located ~ Circular 11 Ground Water Series, Pumping Tests in Colorado, Woodrow W. Wilson, United Stales Geological Survey, 1965. Based on wells located in Section 18, 19, and 3Q Township 1 North, Range 66 West, in Weld County, Colorado. ZHydrologic Investigations Atlas HA-746C, Ceohydrology of the Shallow Aguljers in the Fort Lupton-Cilcrest Area, Colorado, L'. S. Department of the Interior, U. S. Geological Survey.