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C- 2010 -089 NHN Mine <br />PAR No. 2B <br />20- Oct -2011 <br />Page 5 of 7 <br />11. In the Unsuitable Subsoil Backfill Mitigation Plan (beginning on page 4), item 2 describes <br />scarification measures that will be undertaken when necessary. The list includes ripping and <br />chiseling. The second full paragraph on page 6 states that regraded backfill material will be <br />scarified prior to topsoil placement. These two statements appear to contradict one another; <br />in one case, scarification is optional, while in the other it is done as a matter of course. <br />Please review and revise for clarity, as warranted. <br />12. In the last paragraph on page 5, the sixth line gives the overburden thickness (above LDx) as <br />60 to 65 feet. Comparison with the cross sections seems to indicate that the thickness ranges <br />from 60 to 90 feet. Please review, and revise the text if warranted. Additionally, please <br />describe the thickness of the two thin clay (`Bentonite ") beds. <br />13. Soil Suitability is addressed beginning on page 9 of Section 2.05.4(2)(d). At the top of page <br />10 is a table, which purports to be reproduced from Table 2.04.9 -2. (Rather than being <br />found in the NHN application, the table appears to have been derived from the New Horizon <br />Mine permit; the table should be numbered differently.) There appears to be some <br />confusion over the suitability parameters and criteria that will apply to replaced soil, subsoil, <br />and overburden. Appendix I of the WyDEQ guideline lists several parameters that are not <br />included in the table on page 10. Please review the suitability parameters and criteria, to <br />ensure that the application consistently presents the appropriate information. <br />14. Available topsoil resources, as established by the baseline soil survey, are depicted on Map <br />2.04.9 -3 Topsoil Salvage Map. A table is presented in the lower right corner of this map, <br />showing salvage volumes by soil type and polygon. Soil Polygons are numbered 1 thru 45, <br />and are of varying sizes and soil types. Each polygon consists of a single soil type; the <br />volume of soil available is given for each polygon, in BCY (bulk cubic yards). The Division <br />has additional requests regarding the data presented in the table on Map 2.04.9 -3, as follows: <br />a) Soil polygons 9 and 10 straddle the line between the Glasier and Meehan properties. <br />Please divide each of these polygons by landowner, e.g. 9A and l0A for Glasier, and <br />9B and 10B for Meehan. <br />b) Soil polygons 34 and 35 straddle the line between the Meehan and Garvey properties. <br />Please divide each of these polygons by landowner, e.g. 34A and 35A for Meehan, 34B <br />and 35B for Garvey. <br />c) Please also tabulate the soil types, acreages, and volumes by landowner. <br />d) For each polygon, please include the average thickness, in inches, in the table. <br />15. The permit application is thorough in its identification of available topsoil resources, but <br />details regarding handling, storage and replacement of topsoil (and subsoil) are lacking. <br />Map 2.04.9 -3 is a very clear and detailed description of the soil type, location and volume <br />with corresponding polygons. It is not clear from this map or the text description how the <br />topsoil (type and depth) to be salvaged with each panel of the mine will be clearly delineated <br />in the field for the equipment operators who conduct stripping. <br />a) Please describe in detail the technique that will be implemented to salvage the topsoil. <br />Include in the description salvage depths for each panel /soil map unit; volumes of <br />salvaged topsoil; parameters that determine the salvage depth; which soil types will be <br />stored /mixed together and which will be salvaged / stockpiled or replaced separately. <br />