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of the ash disposed of at the site, particularly with respect to ash density. Has Trapper information pertinent to this topic? If so, would TMI be so kind as to provide this information. 27. Please describe and provide a diagram of runoff routing and indicate the receiving water body for runoff emanating from the utility waste disposal area. Trapper Response to Comment 27: With the additional material from N Pit that will be utilized to create the "ridge feature" that appears on the M 12 Map, the water will be routed both north and south of the proposed contours and will drain east into the Johnson Drainage Area, near Johnson #6 Pond. This run-off will be routed through the existing constructed drainage in Johnson Gulch. 24 December DRMS: Trapper's response is adequate. 28. With respect to revised page 3-15a paragraph 6, please discuss why language was removed regarding placement of spoil as a buttress to the North of K pit as per AAI recommendation? It seems to be pertinent information to the description of spoil disposal as per Rule 2.05.3 (6)b. Trapper Response to Comment 28: As a result of the landslide of October 2006, K Pit, which was directly in the slide area, was extensively evaluated from a geotechnical perspective to develop a mining plan that would ensure the safest possible operation for personnel and equipment. In May of 2009 Trapper's Geotechnical Consultants conducted a study that suggested that Trapper should construct a toe buttress at the northern boundary of K pit. This buttress was expected to enhance the stability of K Pit mining and was included in the PR7 Permit Revision document; however, later modeling, based on updated information, indicated that the buttress would not stabilize the slopes for the mining below the K1L-10 cut. It was determined that the stability of this area would be better achieved by reducing the slope through pre -stripping cuts KIL-13 and kll-14s KI L-13 and KI L-14 to the 1 -Seam. Trapper followed this guidance which did not require the construction of the toe buttress. A summary of the primary reasons why the toe buttress information was not included in the PR9 application are as follows: • As mentioned, later modeling based on more accurate information led the Geotechnical consultants to the conclusion that the toe buttress would not enhance the stability of the mining operation and was therefore not recommended, and not constructed. The absence of the toe buttress had no relevance and was therefore deemed unnecessary to the 2018 through 2022 Mining Plan (PR -9 application). • The original recommendation for the toe buttress was based on mining stability and not spoil disposal stability (as per rule 2.05.3(6) b), and therefore was not pertinent to the PR - 9 application. • K Pit has been safely and successfully mined and is presently in the process of being backfilled and reclaimed, thus the toe buttress language has no relevance to the 2018 through 2022 Mining Plan (which involves L Pit and N Pit development) and was therefore not addressed in PR -9. 24 December DRMS; Trapper's response is adequate. Rule: 2.05.4 (2a,c h) Reclamation Plan This is a review of the reclamation plan to achieve post mining land use. Map series M10A provides the mining and regrade time table for the five year permit term, through 2022. The Life of Mine Plan, map M4 illustrates the mining Trapper PR9 2" Adequacy Prepared by: R. Reilley, GISP, M.S. Page 12 Date: December 2018