Laserfiche WebLink
Jerry Schnabel, Bob Stabo <br /> July 11, 2016 <br /> Page 6 <br /> generally unfaulted and unfractured with low permeability. As a result, if any contamination <br /> occurs within the mine site,there will be a hydraulic barrier limiting the potential migration of the <br /> contaminants to the aquifer. A ground water monitoring program will be required by the CDRMS <br /> that will include water quality monitoring. This monitoring program will provide for additional <br /> protection of the local aquifers and nearby wells. Also, pre-blast surveys will be offered to all <br /> structures within one-half mile of the quarry area, and the pre-blast survey will include water <br /> quality and quantity testing of water wells. <br /> The wells to the north and west of the proposed quarry area are upstream and up ground water <br /> gradient from the mine and there is not potential for water quality impacts to occur to these wells <br /> as a result of mining activities. <br /> As indicated above, it appears that the wells to the east of the property are not in direct hydraulic <br /> connection with Little Turkey Creek and may be recharged by sources other than the creek <br /> including but not limited to flow in other drainages and direct recharge from precipitation. <br /> Accordingly, the aquifer is buffered from any contamination risks from Little Turkey Creek and <br /> the proposed quarry. <br /> Impacts to Ground Water <br /> Comment: Comments concerned with the impacts of mining to ground water questioned whether <br /> the mining would generally impact ground water flow'and specifically whether the mining would <br /> impact ground water flow similar to the construction of the NORAD facility which "stopped most <br /> of the ground water supply to large areas down gradient. " <br /> Response: It is not appropriate to compare the proposed mine to NORAD because NORAD is an <br /> underground facility that was constructed deep inside of a mountain. We researched ground water <br /> conditions at NORAD,but could not identify public information on impacts to ground water when <br /> the facility was constructed. However, it is safe to assume that NORAD likely encountered ground <br /> water within the mountain due to the extensive construction and deep excavation associated with <br /> the facility. To the extent that ground water was encountered,that ground water would have either <br /> been drained by the excavation or grouted off. Either way, the construction of the NORAD <br /> facilities would have impacted the local ground water condition as ground water could not have <br /> been allowed to enter the facility. <br /> The excavation of the proposed mine is very different in that it will be constructed in a way that <br /> does not intercept ground water, with the possible exception of portions of the southwest portion <br /> of the mine where we lack data at this time to definitively say that ground water will not be <br /> intercepted. New monitoring well or wells will help to clarify this statement. Even at that location, <br /> if ground water is intercepted, it will occur in a low permeability portion of the rock formation <br /> where ground water is expected to be minimally present. Because of the low permeability's of the <br /> rock formation and because the interception of ground water would occur at or near the water table, <br /> the interception of any naturally present ground water is not expected to result in any significant <br /> mine inflow or ground water drainage. Accordingly, the proposed mining will have little to no <br /> impact on the local ground water systems. <br />