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-8- <br />viii. Details regarding the method to be used to ensure compliance <br />with Rule 4.05.6(8). <br />ix. The method by which sediment accumulation will be monitored, <br />and the level at which sediment removal will occur. The <br />level should never exceed 60% of the total three year <br />accumulation. <br /> 2.05.6.3.2 - Surface Water <br /> 1. This section uses the SEDCAD computer model to project peak flows and <br /> total flow volumes for the Engleville Gulch at a point upstream of the <br />~~. mine area and at a point considerably downstream of the mine area. The <br />, <br />. analysis should have provided the hydrologic calculations also for <br />, , <br />~'-;~ ':, Engleville Gulch inside of the permit area, at the junction of the east <br />,.;.~~ and west forks that join near the south permit boundary, and far a point <br />N` immediately adjacent, and outside of the north permit boundary. <br />2. Also provided are summary hydrology calculations for the actual mine <br />area. These calculations include peak flow estimates for Phase 1, Phase <br />2, the remaining areas outside of these two phases and for the entire <br />permit area. I suggest that the study should have provided peak <br />flow/volume estimates also for the upland areas for which diversion <br />ditches must be designed, and for the specific areas that will contribute <br />flow to the sediment pond. For example, a peak flow estimate is provided <br />for the Phase 1 area, but this value does not account for the additional <br />runoff from the flatter areas below Phase 1 which will be contained by <br />the Phase 1 ditches. <br />3. The methods used to derive the peak flow and volume values in the Applied <br />Hydrology Associates SEDCAD runs are reasonable. <br />4. The requirements of Rule 2.05.6(3)(9)(1), (ii), and (iii) do not seem <br />to be addressed adequately within this application section. <br />Rule 2.05.6(3)(b)(iii) specifically requires a plan for the collection, <br />recording, and reporting of ground and surface water quality and quantity <br />data, according to 4.05.13. Such a plan must be provided. Specific <br />,, elements should include: <br />C <br />~'~ a. Monitoring station locations which are clearly marked in the field; <br />~` b. Monitoring frequency with specific data collection and report <br />submittal dates; <br />c. Specific sample parameters to be analyzed; and, <br />d. Specific methods and equipment to be used for data collection. <br />`,'-`~,~\ 5. Rule 2.05.6(3)(b)(iv) requires a projection of mine related impacts on <br />~~~`~. both water quality and quantity. No such projection is provided. <br />`~ r <br />~~ ~~ ~ <br />(`;``1 ~ ` 1t ``r ~^ <br />. `.. W .h <br /> <br />