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• Natural precipitation, non-consamed irrigation application, and leakage from ditches and canals recharge the mesa gravels; • The ground surface slopes gently from southwest to northeast; • Groundwater rechazge encounters the shale underlying the gravels in the vicinity of the site and saturate the gravels, then moves laterally down gradient (usually in a direction similar to the surface topography); • The Mancos shale underlying the gravels at the site varies in elevation and is not planer, but is undulating and channelized; • The standing water in the neighboring Metcalf Pit is seasonal and varies with irrigation; • Excavation of the gravel deposit to shale bedrock in a mile long north/south strip will diminish or eliminate flows to the Nation's water rights, located below the Spring Creek Mesa surface, dry up the Metcalf Pond, and diminish recharge flows back to Mexican Gulch; • It is unlikely that the operation would be a dry operation 6 to 9 months ofthe year The Division had concerns related to groundwater levels at the site as a result of observations made by staff during the August 8, 2003 preoperational inspection of the site. Standing water was observed outside of the proposed permit area situated at approximately 20 to 30 feet below the ground surface of the proposed Phase I location at the site. Additionally, standing water was observed at a neazby gravel operation within that pit. The applicant was advised of these concerns and was given 3 options as to how to address the groundwater concerns related to the application in a memo from the Division dated September 15, 2003. The applicant opted to propose mining to a maximum of 20 feet below ground surface while monitoring groundwater levels for one year. The applicant chose neither of the other two options, specifically to change the application to include wet mining or to postpone mining for one yeaz while obtaining groundwater levels. The above infarmation was supplied to the Board during the October 30, 2003 heazing and the Board ruled that the permit was approved with the condition that the operator must obtain one yeaz of groundwater level data prior to the commencement of mining at the site. The Lewicki report, mentioned at the beginning ofthis memo, supplies new information that better depicts the conditions at the site, including the following pertinent information: • The applicant is requesting permission to begin mining to a depth of 13 feet (3 feet of topsoil and 10 feet of gravel), instead of committing to a maximum depth of 20 feet, prior to the year's worth of groundwater level data; • Irrigation water enters the aquifer on the terrace through a network of irrigation channels, and travels down to the Mancos Shale, then flows along the dip of the shale to the lower terrace floodplain of the river and enters the river system; • It is likely that no groundwater exists on the mesa once irrigation ceases and the gravels are allowed to drain (based on observations of similaz azeas in western Colorado); • Groundwater levels on the mesa aze a function ofgravel porosity and permeability, the dip of the shale bedrock, the amount of water entering the system, proximity of the infiltration water, and other factors; • The Mancos Shale at the site dips to the northeast at between 1% and 5%; • The 6 test holes dug in March of 2003 showed the depth of the gravel and the strike and dip of the shale; • Based on the author's experience, the conditions at the site and the proximity of the irrigation would result in water levels of only 5 to 6 feet above the shale layer; • An inspection of the mesa slope revealed no evidence of phreatophyte vegetation, nor salt deposits that may be an indication that water had emanated from the slope face;