2012-01-13_APPLICATION CORRESPONDENCE - C2010089 (2)

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C -2010 -089 New Horizon North Mine PARNos. 1- 1A -1B, 2- 2A -2B, 3 Page 16 of 60 additional description including flow direction, gradient and cross- sectional area. Please update page 4 of the application accordingly. The May -2011 response is accepted; however, the reference to Appendix 2.04.7 -2 is incorrect, and should be changed to Appendix 2.04.7 -1 in the second paragraph of revised page 5 (at 2 locations). Ire nt reso&ed in Dee-2011 res s . 5. Aquifer characteristics are described on page 5 but similar to Item 4 above there is reference to the New Horizon 2 permit and also to the New Horizon 1 Mine Area permit. Any pertinent information regarding data for the New Horizon North Mine should be readily available and provided in this NHN application. There is reference to a short term capacity test and transmissivity test at Well GW -N27 which is not located within the NHN permit area, but it is not clear if any actual aquifer testing was conducted or how the data were obtained. Please describe the test(s) performed and describe the methodology for analyzing the data. This information will aid in determining applicable discharge rates as requested in Item 4 above and will allow for a more complete evaluation of potential groundwater impacts and the probable hydrologic consequences. WFC's May -2011 response explains that GW -N27 is in the old backfill, and shows what the expected flow rate will in the "spoils ". The text was revised, and the reference to the NH2 permit was removed. I ent reso i ed in May -21111 reslwnse% 6. Please revise the first sentence under Baseline Ground Water Quality on page 5 because it is misleading. The Division does not approve baseline data collection plans prior to the submittal of anew permit application package. The Division discussed the proposed sample plans with WFC on several occasions in meetings and on the telephone during the planning stages in preparation for submittal of the permit application. The Division only gives approval of applications or plans through the proposed decision process. Please revise the first sentence of the last paragraph of page 5 as follows: "...the planned hole locations, completion techniques, water quality sampling schedules and the water quality sample parameters were discussed with CDRMS for their input and guidance." Please also correct the typo in the first line of that sentence Map 3.04.7 -1 should be changed to Map 2.04.7 -1. Item resolved ed in 1 a g -2x111 response. 7. WFC has done a good job with their initial baseline data collection efforts for ground water information with regard to monitoring well depths and locations. These are consistent with the discussions held with WFC regarding groundwater monitoring sites during the planning phases of this project. However, additional down gradient monitoring and a point of compliance well(s) may be required. The Division agrees with WFC's assessment that there are no current users for the relatively small amount of groundwater that is currently moving through the shallow bedrock zones, overburden and coal toward the crop line to the southwest. Because this groundwater is potentially usable it must be monitored and the extent and magnitude of any mining impacts must be determined. Given the information we now have as provided on geologic cross - sections, piezometric level maps, and the disturbance boundary as shown in the application the Division believes that one additional group of nested wells may be warranted. The reason for this is that the frill extent of the disturbed area is not being monitored in the downgradient direction (i.e., the southwest end of the southernmost mineable block). WFC has other existing monitoring wells in this