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Mr. Tom Schreiner, Division of Minerals and Geology ~~ March 23, 2005 Pages CIVIL RES'aJURCES, LLC mean sea level. See attached Figure 6-R and 6-Ra for a graph of the measured groundwater levels onsite for nine months, which includes the irrigation season of 2004. 9. In conformance with Rule 6.4.7(2)(b), please define the following features: the horizontal distance to surface water features and to groundwater users in the surrounding area; any sources of existing groundwater recharge in the affected land or surrounding area; the kind of drawdown that nearby domestic and/or irrigation water users normally have from their use; the groundwater levels in the various wells or the aquifer after use by nearby domestic and/or irrigation water users during a time of maximum demand on the aquifer (presumably during the peak of irrigation season). Please respond The requested information was discussed in the Groundwater Model Report, however we will restate here. The major surface water feature in the area is the South Platte River located an average distance of approximately one-half mile to the west of the site. The Fulton Ditch Lateral runs parallel to the eastern boundary of the Site (approximately 40 feet to the east of the site) and the recharge from the ditch was incorporated in the irrigation recharge of the Groundwater Model Report as presented in Section 3.8. Sources of irrigation recharge come during mid March to mid October and is primarily from irrigation wells and some ditch shares. Groundwater levels were measured for nine months, which included the irrigation season of 2004 as presented in Figure 6-R in the groundwater model. 10. In order to better understand the regional surface and groundwater system in the area of the proposed operation, and in conformance with Rule 6.4.7(2)(b), please provide a typical cross section diagram that includes the following features: South Platte River, groundwater table during mining, groundwater fable after mining, estimated lake water surface, existing ground, Limits of mineable resource, fulton ditch lateral, the closest wetland, the closest domestic groundwater user, and the closest irrigation water user. Please respond. Figure 2a in the Groundwater Model Report is a typical cross section of the aquifer that shows the approximate location of critical hydrologic features such as; irrigation laterals, rain recharge, irrigation recharge from wells, the approximate slope of the bedrock towards the South Platte River. This section is a general section and distance to wells varies from 50 feet to thousands of feet. There are no jurisdictional wetlands on the property. 11. In conformance with Rule 6.4.4 and Rule 3.1.6(1), please describe the maximum pumping rate necessary to completely de-water all three (3) cells from top to bottom and maintain 2S4 acres of dry pit surface; and the length of pumping period(s) necessary to completely de-water 284 acres of pit surface; the expected drawdown rate of the groundwater surface at the 3 pits; and the natural elevation of groundwater at the pit prior to de-watering. Also, if the operator anticipates using multiple pumps during de-watering and/or pumping from several of more cells during mining, please describe such activities. The Division will consider a maximum "de-watering" disturbance of 284 acres to be de•watered until one or more water storage cells are completely lined, inspected, and approved by the Office of the State Engineer for use as a water storage facility. Please respond As discussed in the Groundwater Model Report, the dewatered mining area were modeled with constant head nodes and allowed to drawdown to steady-state condition. This is a far more conservative approach to estimating drawdown affects then modeling the mining phases with pumping wells. However, a condition in this permit is that the operator may not mine Pond 2 below groundwater until Pond 1 is reclaimed to