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Response to DRMS Adequacy Review — Cotter JD -8 Mine Reclamation Plan Amendment <br />potentially flowing under or through current or proposed mining areas. The applicant <br />needs to submit relevant geological information and a plan to characterize groundwater, <br />or lack thereof for the areas being or proposed to be mined, not just the surface <br />disturbance area. An example cross - sectional map of a site under similar review near the <br />JD -8 is attached for reference. Also a map showing elevations in relation to mining will <br />be needed. A three dimensional evaluation is needed to analyze where compliance and <br />monitor wells may need to be placed. It is suggested that the applicant gather as much <br />data as possible and meet with the Division to discuss the groundwater characterization <br />plan prior to submittal. <br />Cotter response: Additional site - specific information has been compiled for the JD- <br />8 Mine, which includes cross sections and water level information from 559 <br />exploration drill holes. This information was presented to DRMS in a meeting with <br />Cotter and Whetstone on November 30, 2011, to review cross sections and discuss <br />the existing groundwater conditions at the site. The information that was provided <br />at that meeting has been summarized in a technical memorandum, entitled <br />"Hydrogeologic Data Compilation for the JD -8 Mine," dated April 13, 2012, in <br />Attachment 6 (see Revised Supporting Documentation for Exhibit U)). <br />(10) Rule 6.4.21(8) (d) requires the identification and location on a map, in Exhibit C, "of <br />known major fracture systems that affect rock formations under proposed sites ... " The <br />Division does not note the information on Maps C -1, C -2, or C -3. <br />Cotter response: Regional -scale faults and fracture systems were shown in Figure 7 <br />of the EPP. The USGS geologic map has been added to the maps provided with <br />revised Exhibit C — Pre - mining and Mining Plan Maps of Affected Lands. <br />(11) Section 8, Surface water, indicates an unnamed perennial stream 1,270 feet from the <br />mine. The head of this stream indicates the possibility of a spring from groundwater at an <br />elevation below the mine workings. An onsite visit notes that there is a drainage there, <br />but no indications of a perennial stream. Cotter needs to clarify the map and actual site <br />conditions through a drainage reconnaissance report. The Division may require five <br />quarters of sampling under Rule 6.4.21(11) (b) if a spring or seep is discovered as <br />indicated on the maps. <br />Cotter response: Attachment 5 is a technical memorandum entitled "Drainage <br />Reconnaissance Survey near JD -8 Mine" dated January 13, 2012 (see Revised <br />Supporting Documentation for Exhibit U). It provides a summary of the drainage <br />reconnaissance survey that was conducted on October 12, 2011. The purpose of the <br />survey was to determine whether the stream, which had been shown as perennial on <br />a USGS topographic map of the area, was indeed perennial. The field survey was <br />conducted by hydrologists from Whetstone Associates, and included hiking the <br />drainage from its intersection with the DD19 road, down to the valley floor (990 <br />vertical feet), and approximately 2,200 feet across the alluvium on the valley floor. <br />The survey concluded that no perennial seeps or springs occur in the drainage. The <br />drainage is not flowing perennially, and water samples cannot be collected. <br />Page 11 <br />