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b. The as -built drawing (Figure Exh. 7-14SP-1) does not have a scale that functions with <br />electronic copies (it only works for hard copies at proper scale). Please add a scale such <br />as the one on Figure Exh. 7-14SP-2. <br />Tri-State has never scaled a drawing specifically for electronic copies, nor does it understand <br />what that means. All maps, as-builts, etc., are scaled accordingly and submitted, and this has <br />been occurring since the Division started the ePermitting process without any issues. No <br />changes are being made to Figure Exh. 7-14SP-2 as it is scaled correctly. <br />What the Division meant is that the drawing needs a scale bar. Please add this feature <br />to the drawing. <br />4. When reviewing the Streeter Pond SEDCAD: <br />a. No additional response required. <br />b. No additional response required. <br />Please confirm that the stage/storage information in SEDCAD for the Streeter Pond is <br />accurate. Note that the information on the as -built drawing for this pond may not be <br />correct, as the topography does not appear to reflect the current conditions: the large <br />amount of sediment below the fill is not shown and the peninsula near the gate is not <br />shown. If the stage/storage relationship for the pond has changed, this should be <br />reflected in the SEDCAD model. <br />The term 'full stock ponds " is never cited as a "worst case scenario " in Appendix Exh. 7-14SP, <br />Page Exh. 7-14SP-1, as the Division cites. It should be noted this is a statement made by the <br />Division, and is not language proposed on page Exh. 7-14SP-I by Tri-State. <br />As for the stock ponds, given the experience gained from constructing and managing many post <br />mine stock ponds at Colowyo to date, unless there is a constant flow to a stock pond they tend to <br />dry out through evaporation and infiltration after spring runoff is complete. Tri-State believes <br />the stock ponds in the Streeter Pond watershed will be dry or close to dry the majority of the time. <br />However, since the Division seems to have an issue with the ponds being modeled as dry, all <br />three stock ponds have been remodeled with a permanent pool elevation. <br />While checking the initial pool for the SD-1 Stockpond, the Division noticed that some <br />details for this structure in the SEDCAD results pages changed significantly between the <br />November submittal for TR-145 and the January submittal. In particular, the Elevation - <br />Capacity -Discharge Table is quite different. Please explain this change for the SD-1 <br />Stockpond. <br />d. No additional response required. <br />e. No additional response required. <br />VOLUME 2E <br />5. Please explain how the CN values were chosen for the post -mining conditions to model in <br />SEDCAD. In Figure Exh. 7-14ET-2 the large majority of the drainage area has a CN of 62 <br />(925 acres out of 1049 acres). Please explain why that is the worst -case hydrologic condition. <br />