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59. Section 2.4.5.6 and 6.4.21(5) and (6) describe handling of reagents during operations. <br /> During periods of cessation and commencement of closure, a third party chemical <br /> disposal contractor will be engaged to appropriate package, transport and dispose of <br /> any remaining reagents. <br /> 60. Zephyr commits to constructing secondary containment with a capacity of 110% of the <br /> all the storage containers within a given area. <br /> 61. Section 6.4.21(6) is revised to address discharge of groundwater encountered during <br /> mine development. <br /> 62. In order to prevent submission of an SPCC based on preliminary site design and operations (that <br /> will be reviewed by the public) with the potential of revision based on Division input, Zephyr <br /> commits to providing an SPCC plan upon approval of Exhibits C and D that will include <br /> temporary tanks during site development as well as mill operation tanks. The plan will be <br /> submitted prior to commencement of site development, well before mill operation. <br /> 63. The Summary is revised to reflect the use of designated chemicals. <br /> 64. Section 6.4.21(7) is revised to more adequately evaluate the proposed facility. Appendix F of <br /> the submission included the FTSF underdrain, buttresses and contact water pond. Appendix N is <br /> the Jesik Surface Water Management document that includes storm water control structures <br /> and surface water diversion channels. Zephyr commits to providing written notification prior to <br /> construction to establish construction schedule and incremental inspection points. <br /> 65. The FTSF Design report was prepared in 2016 when the Windy Point and Windy Gulch <br /> segments were being mined in addition to the Dawson segment. At that time <br /> geochemical characterization of Dawson and Windy Point tailings had not yet been <br /> undertaken and a Windy Gulch tailings sample was classified as uncertain with respect <br /> to potential acid generation. The author's comments regarding seepage treatment <br /> were made within that context of geochemical uncertainty. Since 2016, the mine plan <br /> has been modified to mining the Dawson segment only. A more comprehensive <br /> geochemical characterization program has been completed on the Dawson segment <br /> tailings providing clarity regarding seepage treatment requirements. Appendix B-GEM <br /> Services Report supersedes Appendix E-FTSF Design Report with respect to seepage <br /> quality and seepage treatment requirements. pH neutralization will not be required. <br /> 66. Section 8.0 Emergency Response Plan is revised. <br /> 67. Appendix N contains Jesik Consulting's Surface Water Management Plan. <br /> 68. Figure 1 in Section 6.4.21(8) is revised. <br /> 69. AMEC provided precipitation statistics in their design criteria for the pre-feasibility design of the <br /> FTSF. They used data from the NOAA Canon City Weather Station USC00051294 (1950- <br /> 2016). The maximum monthly precipitation recorded within the 66-year record was 6.83 <br /> inches. The max annual precipitation is 22.63 inches. Perimeter channels around the FTSF were <br /> designed for the 10-year, 24-hour peak discharge during operations and for the 100-year, 24- <br /> hour peak discharge post-closure. These precipitation frequency estimates were obtained from <br /> NOAA Atlas 14,Vol 8, Ver. 2. The estimates are based on the mean of the annual <br /> maximums. The period of record used is from March 1893 to Oct 2011.In calculating the water <br /> holding capacity of the tailings cover, I used the 24-hour peak rainfall depths listed in AMEC's <br /> design criteria. In summary, yes the wettest year on record was taken into consideration in the <br />