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large, flat area. This flat area will cover approximately 70 acres. Pursuant to Rule 4.09.2(7), please describe how Colowyo plans to divert the runoff from this large, flat area of the pile into stabilized ditches which will safely pass the 100-year, 24- hour storm event. Please include this description in the text under Rule 4.09 - Disposal of Excess Spoil, which begins on Page 20 (South Taylor/Lower Wilson-Rule 4, Page 20) in Volume 12. 22. Colowyo has provided a new Map 45 - South Taylor Fill, which shows the East Taylor and West Taylor Fill plans and cross-sections. This plan view information (less the cross-section details) for the East Taylor and West Taylor Fills is also shown on Exhibit 7, Item 20, Figures 1 C-4 and 1 C-5 - West Taylor Pond Drainage and Figure 1 of the Shannon and Wilson report. There are, however, two discrepancies between Map 45 and Figures 1 C-4 and 1 C-5 and Figure 1 of the Shannon and Wilson report with regards to the plan view for the East Taylor Fill. First, the configuration of the topography lines of the temporary overburden stockpile on the East Taylor Fill is different in the figures as compared to the map. The northwest corner of the temporary overburden stockpile is approximately a 90° angle on Map 45. The same corner of the temporary overburden stockpile on the West Taylor Pond figures and in the Shannon and Wilson report is more of a point. There is also a difference in the southeast corner of the temporary overburden stockpile plan. On Map 45 the southeast corner is basically a flat area, connecting with the southwest and northeast corners of the pile. In the West Taylor Pond figures and in the Shannon and Wilson figure the temporary overburden stockpile again comes to a point. Second, the toe of the East Taylor Fill on Map 45 and Figure 1 of the Shannon and Wilson report is not well defined as such. The plan view on the map and Figure 1 shows the toe of the pile ending abruptly at the 7,700 foot elevation line and not toeing out to a point as shown on Figures 1 C-4 and 1-C5 (where the East Taylor East Tributary Ditch and East Taylor West Tributary Ditch meet up). There is a distinct toe for the West Taylor fill on Map 45 and all of the aforementioned Shannon and Wilson figures. Please review the plan view for the East Taylor Fill on Map 45, Exhibit 7, Item 20, Figures 1C-4 and 1C-5 and Figure 1 of the Shannon and Wilson report and make the necessary changes/corrections to the temporary overburden stockpile configuration and the toe of the permanent fill. 23. The Shannon and Wilson report (21 October 2009 Addendum No. 3 to Geotechnical for Excess Spoil) contains Figure 1 - Temporary Spoil Fill Locations. This is basically the same plan view as shown on Map 45,, with the exceptions noted in question 14 above. Please explain why the Shannon and Wilson report does not show the E-E' cross- section that is shown on Map 45 and include if necessary. 24. The original July 2006 Shannon and Wilson Study concluded that no rock toe buttresses or key-way cuts are required for the South Taylor valley fills because the designed slopes were 3.8:1, which are less steep than the 2.8:1 slopes which would have possibly required toe buttresses or key-way cuts, pursuant to Rule 4.09.1(10). In TR-81, the temporary fill outslope is proposed to be 2.5:1. Section 4.09.1(10) requires that, "where the slope in the disposal area is steeper than 2.8h: l v... keyway cuts or rock toe buttresses shall be constructed to stabilize the fill. Where the toe of the spoil rests on a downslope, stability