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Trapper Mine; TR115 <br />Page 2 <br /> <br />DRMS Response: The Division has the following adequacy comments: <br />1.1. With regard to the Deal Diversion SEDCAD model, the Division must review all <br />variables used to derive the structure outputs. Based on the Division’s review all <br />variables appear adequate for the diversion. However, the structure networking and <br />individual structures associated with the drainage of the watershed require clarification. <br />The SEDCAD model for the Deal Diversion identifies the watershed itself as structure <br />#1 and the Deal Diversion as structure #2. Based on proposed Map M51, the Deal <br />Diversion is identified as structure #1 flowing into a drainage labeled stru 1, sws 2, <br />which flows into Junction 1, which flows into the Deal 1 Pond. In order for the Deal <br />Diversion design to be adequate, every structure must have a designated down-gradient <br />structure. Based on the Deal Diversion design the diversion does not have a designated <br />down-gradient structure. Please provide clarification to the Deal Diversion model to <br />discuss all linkages and appropriate run-off calculations derived from the linkages <br />to ensure that the diversion is adequately designed and to account for the <br />additional run-off to all down-gradient structures. <br /> <br />1.2. Based on the information in comment #1 above. A revised design for the Deal 1 Pond <br />which would include the Deal Diversion run-off, was not included in the TR115 <br />submittal. In order to ensure that the Deal 1 Pond will have the adequate capacity to <br />contain and treat the run-off or inflow entering the pond, the Deal 1 Pond design must <br />include the additional inflow resulting from the 23.74 acres of run-off from the deal <br />diversion. Please submit a revised Deal 1 Pond design that includes the additional <br />inflow as a result of the Deal Diversion SEDCAD model or provide the Division <br />with a justification that the current design is adequate. <br /> <br />1.3. As noted in comment #1 above, the Division must review all variables used to derive the <br />structure outputs with the Deacon/Jeffway Diversion. Based on the Division’s review <br />all variables appear adequate for the diversion. However, the structure networking and <br />individual structures associated with the drainage of the watershed and the resulting peak <br />discharge require clarification. The SEDCAD model for the Deacon/Jeffway Diversion <br />does not provide a description of the structures associated with the model. It appears <br />that the design includes two ponds as structures. These additional ponds are not noted in <br />any proposed or approved text or on any proposed or approved Maps. Based on the <br />Division’s review of Map M51, the structure networking is as follows: South <br />Section=>Central Section=>North Section=>Junction 1=>East Flume Pond. No <br />additional Ponds are noted on Map M51. Please clarify the Deacon/Jeffway Diversion <br />model to identify the correct network structuring and the inclusion of the two <br />ponds identified as structures #8 and #10 within the SEDCAD model. <br /> <br />1.4. Based on the information in comment #1.3 above. A revised design for the East Flume <br />Pond which would include the Deacon/Jeffway Diversion run-off, was not included in