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;~ <br /> <br />the caldera in the immediate area of the mine is characteristically <br />of relatively low pH. Examples of this are the waters from <br />monitoring wells CRMW-2A and 2B and from the spring under the leach <br />pad in Arequa Gulch. No significant beneficial use is apparently <br />being made or can be made of this water. <br />Admittedly, I have not located any shallow ground water quality <br />data in the area of the Ironclad waste dump. There are, however, <br />two CC&V wells listed with the State Engineer and located in the <br />northern portions of the Cresson Permit area, ie. in Sections 18 <br />and 19, so it is possible some use. of ground water in this area is <br />being made. Without quality data or more information, however, that <br />use cannot be established as conventional or potentially <br />significant. Consequently, at this time, there is no clear evidence <br />of even shallow ground water having a quality allowing domestic or <br />agricultural use in the areas immediately adjacent to the Cresson <br />Mine pits and waste dumps, ie. areas where such water could most <br />readily be impacted by the acid rock drainage from the pits and <br />waste dumps before that drainage could be fully neutralized. In <br />such a case, I don't think it practical for the Division to pursue <br />this compliance issue for areas inside the caldera. why require <br />neutralization of the acid drainage from the pit and waste dumps if <br />impacts on the quality of the local groundwater which adversely <br />affect its use or reasonably potential future use cannot be <br />demonstrated. <br />Outside of the caldera, groundwater quality is better. There is <br />apparently not the same level of exposure to sulfide rich materials <br />or to drainage from such materials. In the Wilson Gulch area, <br />groundwater of potential domestic quality has been reported in CC&V <br />monitoring wells WCMW-2-65 and WCMW-1-404. In Arequa Gulch below <br />the heap, there is ground water of potential agricultural use <br />reported from CC&V monitoring wells CWMW-3A and 3B. These waters <br />are not now used for such purposes but appear to have the potential <br />for such uses. <br />The Wilson Gulch locations are not far removed from the toe of the <br />Arequa Gulch waste dump which appears to extend beyond the margin <br />of the caldera. As a result, it seems reasonable to require that <br />the operator make some effort to address the potential of the dump <br />to generate acid drainage, ie. either by attempting to neutralize <br />the drainage or instituting some preventative measures to reduce <br />the exposure of the dump material to the atmosphere and to meteoric <br />water. As I understand, however, the operator has committed to <br />"cap" this waste dump which is a practice based permit condition <br />that could reduce the potential of this material to generate acid <br />and metals laden ground water. Since capping could probably be <br />argued by the operator as being adequate to deal with the <br />Division's concern, I have to question the practicality of pursuing <br />the potential for acid rock drainage from the dump in this area as <br />a compliance issue. This should not, however, prevent the Division <br />from insisting upon numerical permit conditions being set and <br />Points of Compliance established for the protection of the <br />downgradient groundwater in Wilson Gulch and Arequa Gulch. <br />