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<br />-~- <br />4. No designs or supporting calculations for an emergency spillway for <br />Pond A are included in the application. This information must be submitted. <br />5. Storm King proposes to use diversion ditches to reduce the sediment <br />inflow into Pond B. Designs for these diversion ditches must be submitted in <br />order for the Division to evaluate whether the sediment delivery ratio used is <br />appropriate. <br />Storm King's consultant calculated a sediment volume of 1.3 acre-feet for <br />Pond B during years 1-5 and 4.0 acre-feet during years 6-25. This apparently <br />conflicts with Table 4.2-1 which indicates sediment storage volumes of 0.9 and <br />3.8 acre-feet, respectively, please clarify. <br />6. It is not apparent from the sediment control plan and Figure 4.2-19 how <br />runoff will be directed to the sediment pond at the surface facilities area. <br />A detailed plan for both the low production scenario and full production <br />scenario must be submitted. Unless some major grading is done, it appears <br />that much of the runoff will never enter the sediment pond. <br />7. The Vulcan Ditch presently passes through the area to be disturbed by <br />surface facilities. How will drainage in this ditch be maintained. <br />Use of Explosives -Rule 2.05.3(6)(a) <br />The application presents a brief statement of intended compliance with our <br />regulation's blasting requirements. The application must be amended to <br />conform with the specific requirements of Rule 2.05.3(6)(a)(i) through (vii). <br />Rule 2.05.3(8) Coal Processing and Non-Coal Processing Waste <br />The application proposes the construction of a 300 foot high coal processing <br />waste slurry embankment. The application contains a geotechnical <br />investigation of the proposed site and a structural design analysis. For a <br />structure of this type and magnitude, the application must contain thorough <br />and detailed reports of geotechnical site investigation, stability analysis <br />and engineered structural design, in compliance with requirements of Rule <br />2.05.3(8), 4.09, 4.10 and 4.11. Several deficiencies exist within the <br />application presentation, which will require amendment. <br />1. The "seismic exposure" portion of the application has been referred to <br />the Colorado Geologic Survey for review. If their review identifies any <br />inadequacies, appropriate supplement comments will be forwarded to the <br />applicant. <br />2. The application states, on page 16 of appendix 3.3-3a; "...the course <br />refuse would be made up of shales and sandstones that will vary in strength <br />and durability from hard, durable rock to softer, slaking rock, which would <br />likely break down under construction equipment. The course waste material <br />that is unsuitable for construction of the embankment should be placed within <br />the impoundment area and additional borrow material substituted for embankment <br />fill." The.aQplicant should elaborate on the techniques to be used to test <br />and segregate the run-of-the-plant course refuse material. <br />