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being mined is generally less than 30 gallons per minute. Most of the water appeazs to be entering the mine workings from low permeable joints or fractures in the underground mine roof rock. The quantity of water entering the mine workings decreases over time. Thus, encountered water appears to be entering from perched zones above the mine workings and not from recharge at the outcrop. Geological and observation well data suggest faulting has created hydrological barriers to water moving down dip. The amount of water available down dip is limited in quantity and exhibits increasingly higher TDS values as water migrates down dip. In addition to the geologic structure inhibiting groundwater flow, the limited recharge area at the outcrop and subcrop (Figure 1) and the poor hydraulic characteristics of the aquifer units themselves further demonstrate that the use of these aquifers can not practically support a reasonable cost effective future water supply uses. 4.4 Groundwater Aquifer Classification The Division and the Colorado Water Quality Control Commission have not classified the groundwater in the aquifers in and adjacent to the Mine. According to DRMS guidelines, the aquifers should not be classified because the aquifers associated with the mine probably will not be used to support future domestic or agricultural uses because of poor water quality, and the economic unreasonableness of tapping deep (>300 feet), low- yielding aquifers. 4.5 Water Riehts Over 125 water right records within two miles of the permit boundary were obtained from the Colorado State Engineers office and reviewed (Attachment A) to identify potential groundwater uses within two miles of the Mine permit boundary. Our review indicates that no groundwater wells have been drilled to depths greater than 300 feet for domestic or agricultural uses. The only wells that produce more that 15 gallons a minute aze in the River alluvium and no domestic or agricultural wells are in the units mined or proposed to be mined by Bowie. 5.0 Conclusions and Recommendations As discussed above, aquifers within the Mine permit boundary and those down gradient from the Mine are not used for domestic or agricultural uses. These aquifers do not have a "classification" to support existing or future uses, have poor water quality at depths greater than 300 feet deep and exhibit poor aquifer hydraulic characteristics, including low yield. Considering these factors, along with the high cost of drilling wells to these depths, we conclude that the likelihood of water wells tapping aquifers beneath the BLM and USDA-FS managed lands in the future at depths greater than 300 feet is remote at best. On this basis, Bowie requests a variance from installing groundwater monitoring compliance wells in excess of 300 feet deep.