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Mr. Tom Schreiner May Z5, 2005 Page 4 Colorado water laws and regulations and Colorado water quality laws and regulations (NLRB Rules, §3.1.6(1)(a) and (b)). Also, the Rules require a ground water monitoring program on acase-by-case basis where an adverse impact on ground water quality may be reasonably expected (NLRB Rules, § 3.1.7(7)). Additionally, the CMLR Act states "disturbances to the prevailing hydrologic balance ... and to the quality and quantity of water in surface and groundwater systems...shall be minimized (Act 34-32-116(7)). Review of the proposed site indicates the mining operation will directly affect both the surface and ground water systems for the following reasons: The fractured aquifer yield is not poor as claimed by the applicant. Wells developed into this aquifer in the vicinity of the proposed quarry site yield significant ground water (10-100+ gpm). For example, one of Black Hawk's wells (approximately 4 miles northwest) produces 130 gpm,Black Hawk/Central City Sanitation District's (BHCCSD) well (within 600 feet of the subject property) produces more than 20 gpm, and the Cleaz Creek Convenience store's well (within 400 feet ofthe proposed quarry entrance) yields 20 gpm. • The fractured aquifer is not classified as nontributary. Pumping tests in the area demonstrate that the fracture system is hydrologically connected to the surface water system and is, therefore, tributary. Furthermore, the State Engineer administers water in this aquifer as tributary and subject to the priority system. • Well data in the vicinity of the proposed quarry site indicate that ground water will be • encountered with mining operations and that dewatering will be necessary. Review of 300 wells within four miles of the site, shows the median depth to water is 120 feet. None ofthe wells have a depth to water greater than 500 feet and only two percent exceed 400 feet. Review of the well data also indicates that the water table is generally parallel to the ground surface. Therefore, 1) the ground water system is recharged in the upland azeas, Z) the ground water flows approximately parallel to the slope of the land, and 3) ground water discharges to the perennial streams in the azea including North Clear Creek (adjacent to the site] and Cottonwood Creek (within the site boundaries). There is a risk that the quality and quantity of local ground water supplies will be adversely affected. The BHCCSD well (permit number 59840-F, Augmentation Case No. 94C W036) and the convenience store well aze completed in the fracture zone of the Black Hawk fault (see Figure 1). This fault zone is hydraulically connected to the fractured aquifer underlying the proposed quarry site. Therefore, the existing wells aze dependent on recharge that currently occurs on the project site and flows across the site to the northeast. Significant dewatering of the quarry will very likely reduce the yield from the existing wells. • There is also a concern that the proposed mining operation (blasting, etc.) may introduce contaminants to the interconnected fractures supplying the water to the nearby wells and negatively impact the water quality. Additionally, the proposed blasting could plug the interconnected fractures and reduce or eliminate the yield from these existing wells. The permit should be denied because: LEONARD RICE ENGINEERS, INC.