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Preliminary Adequacy Issues for CN-01 10 <br />May Day Idaho Mine Complex <br />35. Figure C-6 does not provide the information required by Rule 6.4.21(8)(a). Please <br />provide the information required under Rule 6.4.21(8)(a). <br />36. Please provide the information required under Rule 6.4.21(8)(b), (c), (d) and (e). Please <br />identify all known aquifers and related subsurface water bearing fracture systems within <br />two miles of the affected lands. Please illustrate the descriptions provided in Section <br />6.4.20(8) of Exhibit T, with geologic and/or stratigraphic cross-sections, underground <br />mine maps and surface maps. Please identify and locate on maps, known fracture <br />systems. Please provide a plan whereby the general direction and rate of flow of <br />ground water in the aquifers and fracture systems may be verified. Please provide a <br />plan whereby hydrologic testing and analysis of the ground water in these systems may <br />occur. <br />37. In sections 6.4.20(8), (9), (12) and (19) of Exhibit T, Environmental Protection Plan, the <br />Applicant proposes to characterize ground water and establish baseline conditions by <br />sampling from only one location; the discharge from the collapsed Idaho No. 1 Adit. The <br />application proposes the same as the only ground water monitoring location and the <br />Point of Compliance for the life of mine. <br />According to the application, the permit area includes 274.7 acres of steep slope <br />topography with complex geology, cut by a series of east-west faults with substantial <br />vertical displacement along the faults. Section 6.4.20(8)(b) of Exhibit T indicates the <br />ore-bearing veins are located below the reported aquifer. <br />Such conditions suggest a highly variable ground water system. The application fails to <br />demonstrate how the ground water system for the entire permit area can be <br />characterized at a single sampling location. The proposed plan does not satisfy the <br />requirements of Rule 6.4.21(9). <br />The discharge from the collapsed Idaho No. 1 Adit should be included in the ground <br />water monitoring plan but the plan must also include monitoring wells at up-gradient <br />locations, down-gradient locations, and in the immediate area of the mill facility and <br />underground tailings disposal locations. Please submit a ground water monitoring plan <br />showing the approximate locations, depth, and method of construction for the <br />monitoring wells sufficient to characterize ground water conditions and verify <br />compliance with ground water regulations. Please provide a list of parameters and <br />detection limits for ground water analysis for Division review and approval. Please <br />ensure the list of ground water parameters includes the full suite of parameters listed <br />on Table 1 through 4 in CDPHE Regulation 41, Basic Standards for Ground Water. If the <br />Applicant desires a variation from the full suite of parameters and detection limits listed <br />in Regulation 41, please submit such request for Division review. <br />After the five quarters of ground water data have been submitted and reviewed the <br />Division will approve baseline conditions through the permit modification required <br />under paragraph (3)(b) of the Joint Stipulation.