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The Division accepts the removal of any excavation from the 100 year flood plain as negating <br />flooding impacts in so much as is reasonable and practical. <br />3. Natural Drainage: Deep Cut has a concern of impacts to natural drainages and erosion <br />control. <br />The applicant has applied for a storm water and discharge permit as well as consulted with the <br />Corp of Army Engineers. The pit will naturally capture any run-on from precipitation events <br />but is required by the Office of State Engineer to release it within 72 hours. Dewatering of the <br />pit will include pumping to a sedimentation pond prior to any release into the river. The <br />discharge is monitored by the Colorado Water Quality Division. Rule 3.1.9 (3) requires all <br />stockpiles of topsoil to be placed to minimize erosion and disturbance. The topsoil stockpiles <br />if left in place for longer than one growing season shall be protected with a protective cover to <br />prevent such erosion. The Corp of Army Engineers during a site visit noted no problems with <br />the river, but noted possible wetlands impact issues. With the sedimentation pond and other <br />erosion control features silting of the intake inlet should not happen. If for any reason silting <br />did occur the Division would consider this an off site impact subject to enforcement and <br />corrective actions which would include clearing the inlet and covering any costs associated <br />with re-establishment of the system at that point. <br />4. Natural mround water in the area. Deep Cut has raised a concern that excavation during <br />low water times will draw water away from the inlet and ditch into the created ponds. <br />DRMS staff hydrology person, Kate Pickford, noted during a review of the permit that the <br />concerns of the draw back from either the inlet or ditch appears unfounded. This is based on <br />the principal that groundwater levels in the pond will reflect what the natural levels are for the <br />entire area. The ponds will not pull water from the surrounding surface area resulting in a <br />higher level in the ponds than adjacent groundwater. The mining plan was revised to include <br />water discharging into the inlet via a discharge permit. This procedure may actually improve <br />water availability within the inlet as subsurface groundwater will be placed in the inlet when <br />operating even when surface waters dry up or decease significantly. DRMS staff feels this <br />issue has been addressed. <br />5. Weed infestations. Deep Cut has concerns regarding a weed managementplan. <br />Rule 3.1.10(6) states methods of weed control shall be employed for all prohibited noxious <br />weed species. All permitted sites are required to control both annual and noxious weeds on <br />active and reclaimed areas. DRMS inspects all permitted sites. Because no noxious weeds <br />were observed during a site visit a specific control plan is not required at this time. Should any <br />noxious weed infestation be observed the permit holder will be required to develop a control <br />plan approved by the Division and the local weed control authority. No permitted site can be <br />released if an infestation of noxious weeds has been noted and the operator cannot demonstrate <br />that all reasonable measures have been taken to control the infestation.