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Colowyo, C1981 -019, PR3 adequacy No. 3 <br />July 22, 2011 <br />primary sediment control system should be addressed as small area exemptions if they will not <br />report to the sump /sediment pond. Please describe in detail, using permit text narrative, maps, <br />cross - sections, and other information as necessary, as to how future reclaimed areas in the <br />Cullom Lite pit will be routed around the temporary spoil pile that will block Collom Gulch. <br />The application remains inadequate. CCC explains that runoff will be pumped around the <br />temporary spoil pile that will block Collom Gulch, however it is the professional opinion of <br />DRMS staff that the area where the runoff will collect can be described as an impoundment and <br />that it design is needed. <br />The response is inadequate. In the SEDCAD model for the Roadside Impoundment, there <br />appears to be a contradiction between the Structure Summary table (page G -6 in Exhibit 7 -23) <br />and Figure A -2 of Exhibit 7 -23. In the figure, the south side of the spoil pile (51.97 acres <br />according to text on page G -1) is shown as a contributing area, but in the summary table it <br />appears that this portion is missing. Please revise or clarify. <br />Two sedimentation ponds have been proposed with PR -03: the Little Collom Pond and the Little <br />Collom Sump. Specific information is provided in application sections 2.05.3(4); 4.05.6; Exhibit 7, <br />Item 23; Exhibit 7, Item 26 — Collom Pond Design Maps; and Exhibit 23, Item I Shannon & Wilson <br />Geotechnical Study (S &W). Text in 2.05.3(4) of the application directs the reader to Vol. 1, Section <br />2.05 of the permit for pond construction and maintenance details and to permit Section 4.05.6 for a <br />discussion of quarterly inspections. <br />2.05.3(4)(ii) Detailed Design Plan <br />Detailed designs are provided in Exhibit 7 Item 23 (Figures I and 2). Gcotechnical analysis <br />and stability evaluation for the Pond Embankment are found in S &W pp. I4 -15 and Fig. 1 1 . <br />(A) The designs have been certified by a registered P.E. No revpmese required. <br />(L3) The Division notes several discrepancies between the notes on S &W Fig. I I and the <br />notes provided with Exh. 7 Item 26 Fig. I, as follows: <br />Fill Materials: S &W lists soil types SM, SC, GM. GC and CL as "acceptable ", while <br />Fig. I lists SC. CC, SL and CH. S &W states that high plasticity clay and silts (C II and <br />ML) arc "unacceptable ". Fig. I does riot exclude these materials, and in tact lists CH as <br />„acceptable ". <br />This item has been resolved with the August 9, 2011 submittal. <br />Fill Placement and Compaction: S &W recommend that the moisture content be <br />within 0to I -3 °" of optimum moisture content. Fig.I n:quires CMC i; -' "5. <br />This item remains inadequate. Please revise the map to agree with the values stated <br />in the cover letter, -2% to +3 %. The values stated on the map, -3% to +2 %, are <br />incorrect. Please correct Exhibit 7, Item 26, Figure 1, to reflect the correct moisture <br />content values. <br />