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extensive discussion of overburden geochemistry in the PR-7 area (Section 2.7.2.3; Pages <br /> 2-391a through 2-391z) and Section 2.74, Pre-mining Conditions— Surface Water. No <br /> additional text is proposed that refers to or explains the significance of the figure. <br /> Please explain proposed Figure 2.7-5. <br /> Rule 2.04.7(1)Hydrology Description; Groundwater Information <br /> DRMS 28 February 2023 <br /> 41. Section 2.7.5.1d (Page 2-462o) describes aquifer characteristics of the I and J pits, <br /> it was last updated with PR-10. <br /> Please update Section 2.7.5.1d to address the mine plan proposed with PR-11. <br /> 42. The water levels in the Twentymile Sandstone,Third White Sandstone, Second White <br /> Sandstone and Alluvial Aquifers are presented on Map 54G,which was last updated with <br /> PR-7 in 2014.The map shows projected contour lines at 100' intervals of the potentiometric <br /> surface in each of the named aquifers,from which the direction of groundwater flow can be <br /> inferred.The map suggests that groundwater flows generally to the NNW across most of the <br /> permit area in all three of the identified bedrock aquifers.There is an anomaly in the Third <br /> White Sandstone in the region of the PR-I I addition to the permit area(see Figure 2),where <br /> the 6300' contour line is shown curving dramatically around by 180°. If this line were <br /> accurate groundwater flow in the Third White Sandstone would be to the W,or possibly <br /> SW,beneath the proposed I Pit West,and neither of monitoring wells 81-03A or CY-3 <br /> would be downgradient of the proposed disturbance. Based on the information available in <br /> the PAP,the Division finds the projected potentiometric surface shown on the currently <br /> approved Map 54G implausible,particularly given that no such anomaly is shown in the <br /> Second White Sandstone which overlies it.According to Figure 2.7-4(page 2-356)the axis <br /> of the synclinal basin is approximately 2 miles to the north, so there is no structural rationale. <br /> Given that the Third White Sandstone is immediately below the G-seam(according to figure <br /> 2.7-18p,page 2462b),further characterization of this aquifer in the PR-I I area is warranted. <br /> Characterization of the the alluvial aquifers in the three drainages in the west of the permit <br /> area appears to be lacking. <br /> (a) Please discuss the anomaly in the Third White Sandstone aquifer described <br /> above. <br /> (b) Please update Map 54G with the most recent data available to show the best <br /> possible prediction of the potentiometric surface in each of the named aquifers. <br /> (It may be necessary to collect data from another point south and west of 81- <br /> 03A and CY-3) <br /> (c) Depending on the response to(a) and(b),please propose an additional <br /> downgradient monitoring well in the Third White Sandstone if necessary. <br /> (d) Please discuss the characterization of the alluvial aquifers in the west of the <br /> permit area. <br /> 17 <br /> Trapper Mine PR I ADQ No 2 <br /> 2023 February <br />