5.5. SR 04-04-2011 - Laserfiche WebLink

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Minnesota Department of Natural Resources (DNR) Central Region, March 7, 2011 From a natural resources perspective, the proposed project does not require the preparation of an Environmental Impact Statement (EIS). However, the following comments are for your consideration. Please be advised that the document posted online, along with the agency distributed copies, appeared to be missing some of the attachments referenced in the document. Item 5 and Item 16 made reference to a Figure 5, and item 11 b referenced an Appendix A. At this time it does not appear that these omissions warrant concern for the potential of significant impacts. These errors should, however, be noted for reviewers and these documents should be made available. So noted. The EAW does not directly indicate the proposed mining depths, or the potential for the mining operation to impact groundwater. Item 19 indicates that the minimum depth to groundwater is 20 feet. The description of the stockpile locations provided in Item 7 indicates that the pit floor would be approximately 20 feet below grade. While Figure 3, Mining Excavation Plan, indicate that depth would be a minimum of 990 feet mean sea level (with surface elevations varying from 1,000 to 1,025 feet mean sea level) and that actual excavation depth may vary depending on the quality of aggregates encountered. Given this information, it may be possible that the proposed activities could encounter and/or impact groundwater resources. It does not appear from review of other Item information provided that the proposed project includes in-water mining activities. The potential to impact groundwater should be addressed, or the information discussed above should be clarified so that it is clearly understood how this potential impact will be avoided. The project does not involve "in-water mining activities" and groundwater resources will not be encountered and/or impacted. Based on drilling work to define the aggregate resources, the groundwater elevation occurs at approximately 970 feet mean sea level. This explains the information in Item 19. The 990 feet mean sea level for the Mining Excavation Plan indicates the lowest elevation. There is a potential that excavation depth could be less than the planned depth based on quality of aggregates encountered. The City of Elk River will place specific requirements within the Conditional Use Permit (CUP) that no excavation occur below the groundwater table. The DNR Natural Heritage Database letter dated November 15, 2010 identified that Blanding's turtles (Emydoidea blandingill), astate-listed threatened species, have been documented in the vicinity of the proposed project. The letter also stated that the response to Item 11 b of the project EAW should clearly discuss potential impacts to Blanding's turtles and identify any avoidance or mitigation measures that will be implemented. Possible avoidance or mitigation measures were included in the Blanding's turtle fact sheet that was attached to the letter. While the EAW document acknowledged this comment, the document does not indicate how or to what extent the