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Mr. Jack Henris July 13, 2016 Page 12 m:\min\tc1\_teller\m-1980-244 cc-v\am-11\m-80-244-am-11maincommentr12016-07-13.docx percent operating level in the PSSA’s? If not, what is the purpose of the five feet of freeboard? 47. Appendix 7, Figures 4 and 5. These two figures show a constant Squaw Valley [sic] PSSA pond volume over 225 months. This is counterintuitive unless the assumption is to turn off the pumps once the PSSA water level falls to a given level, which is not what the Division staff has observed in the field for the Arequa Gulch VLF operation. Please clarify the assumption and provide the Division assurance the proposed operational plans for the Squaw Gulch PSSA are reflected in the water balance. 48. Appendix 7, Figures 11, 12, 15, 16, 19, 20, 23, 24, and 27. These figures show a constant PSSA pond volume over the entire simulation period. This is counterintuitive unless the assumption is to turn off the pumps once the PSSA water level falls to a given level, which is not what the Division staff has observed in the field for the Arequa Gulch VLF operation. Please clarify the assumption and provide the Division assurance the proposed operational plans for the Arequa Gulch PSSA’s are reflected in the water balance. 49. Appendix 7, Table B.1. The water balance is dated November 2015. The Division received an update to the Squaw Gulch PSSA elevation-storage capacity based on survey data in January 2016. Does Table B.1 reflect the as-constructed survey or does it need to be updated? Volume IV – Appendices 9 through 14 50. Appendix 9, Water Purchase Agreements. These agreements are signed by AngloGold Ashanti (Colorado) Corp. representatives for Cripple Creek and Victor Gold Mining Company, and not Newmont representatives. Are these water purchase agreements still valid as the Cripple Creek and Victor Gold Mining Company is now controlled by Newmont? 51. Appendix 10, Chicago Tunnel Site (p. 5). The second paragraph states “An existing 18- inch culvert beneath the Cripple Creek access road will be replaced with a 24-inch culvert that can discharge the 10-year flow. Excess flow above 17-cfs will spill over a constructed riprap spillway and flow across the access road in an armored swale”. a. Why not use a larger culvert or put two 24-inch culverts in place of the existing 18- inch culvert and pass the entire 100-year peak flow without overtopping the road? b. If not, how is traffic to cross the riprap-lined spillway? 52. Appendix 10, Chicago Tunnel Site (p. 6). The Chicago Tunnel site is to be considered a designated mining operation (DMO) with the approval of AM-11. As such stormwater conveyances are required to pass the peak flow resulting from the 100-year, 24-hour design storm. The first paragraph states the upper channel has been designed for the 10-year/24- hour event. This channel must be redesigned to convey the 100-year event. 53. Appendix 10, Chicago Tunnel Site Detention Pond (p. 6). The third paragraph implies that the entire 0.46 acre feet of storage capacity can be used to attenuate the peak flow. All spillways must be designed to pass the 100-year design flow assuming the pond is full to