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3. The Applicant has provided the locations of the settling ponds. In addition, please specify the <br />depth of the dewatering ponds and the location and dimensions of dewatering trenches. This <br />information is required to assess the stability of the pit slopes during mining and the possible <br />impacts to man-made structures in the event of a slope failure. <br />4. The Division understands the dynamic nature of mine sites makes it difficult to identify <br />stockpile locations and volumes. However, the Division requires this information in order to <br />calculate the financial warranty estimate which includes factors such as haul distances of <br />topsoil. Please specify the location and volumes of topsoil on the Mining Plan Map. Any <br />changes to the topsoil stockpile locations and volume amounts can be addressed through a <br />Technical Revision at a later date. <br />5. According to the Mining Plan, the operation will consist of four individual tracts. Please <br />commit to delineating the boundaries of each tract as they are disturbed. <br />6.4.7 Exhibit G - Water Information <br />6. The Applicant has stated a Technical Revision may be submitted to allow for the lining of the <br />pits. The Division considers lined pits to be a developed water resource, which would <br />constitute a significant change from the proposed post-mining land use of <br />industrial/commercial and would require an Amendment rather than a Technical Revision. <br />7. The Dewatering Evaluation provided by CGRS states that groundwater will be pumped into <br />unlined ponds east of the mine. However, the Mine Plan states water will be pumped into the <br />upland drainage seep and will flow to the Cache La Poudre River. Please clarify this <br />discrepancy. <br />8. The Dewatering Evaluation provided by CGRS was carried out under the assumption only <br />one pit will be dewatered at a time. The Mine Plan provides for simultaneous extraction of <br />the pits by posting of additional warranty. Please clarify if the Operator will only dewater one <br />pit at a time. If the Operator anticipates dewatering the cells concurrently, then the <br />Dewatering Evaluation must be revised to reflect this. <br />9. The Division is currently reviewing CGRS's Dewatering Evaluation and additional <br />comments will be forthcoming. <br />10. The Applicant has stated their stormwater discharge permit allows them to discharge into the <br />seep ditch at an average rate of 7.2±MGD. If water is discharged into a ditch that is unlined, <br />it may be prone to erosion. The Applicant should provide the Division with specifications as <br />to how much water the ditch can carry without experiencing erosion. <br />11. Much of the site is located within floodplain of the Cache La Poudre River. Whenever <br />mining will occur within 400 feet of the river channel, a flood analysis and flood control plan <br />must be submitted. The flood analysis should quantify the velocity and volume of flows <br />expected on site from a 100-year flood event, as well as the elevation of the 100-year base <br />flood event and its relation to the elevation of any proposed spillways and lake shore