Laserfiche WebLink
<br />ATTACHMENT 2 <br /> <br />AU6 1 S 1994 <br /> <br />~ <br />- <br /> <br />.\ <br /> <br />LIi5~CH <br /> <br />B.A. LIESCH ASSOCIATES, INC. 13400 15TH AVE. N. MINNEAPOLIS. MN 55441 612/559-1423 FAX: 612/559-2202 <br />GROUNDWATER MONlTORING RECOMMENDATIONS <br />FOR PROPOSED <br />SHIEL Y COMPANY GRAVEL PROCESSING WELL <br />(AUGUST 1994) <br /> <br />INTRODUCTION <br /> <br />. <br /> <br />Shiely Company (Shielyl proposes to expand their sand and gravel mining operation within <br />the Elk River Sand and Gravel Mining District. The proposed expansion will include <br />utilization of an existing Mt. Simon - Hinckley well to provide process water. The existing <br />well (unique well #217977) is currently not in-use, but is permitted by the Minnesota <br />Department of Natural Resources (DNR) as a well for withdrawal of up to 50 million <br />gallons per year (DNR Permit #913086). It is understood that the well will provide a high <br />capacity water supply (more than 10,000 gallons per day or 1 million gallons per year) for <br />the mining operation. Recommendations for monitoring the effect of the high capacity <br />well use on the groundwater resource are provided herein. The proposed monitoring is <br />intended to provide data that can be used to further characterize aquifer response to <br />pumping, provide baseline data and identify and minimize potential impact on residential <br />water supply wells located outside of the mining District. <br /> <br />Development and implementation of a groundwater monitoring program was recommended <br />in the Elk River Sand and Gravel Mining District EIS and further recommended by the DNR <br />following their review of the EIS. The monitoring recommended in the following sections <br />includes installation of monitoring wells in the mining district buffer zone, water level <br />monitoring and background water quality monitoring. <br /> <br />RECOMMENDED MONITORING WELLS <br /> <br />Two monitoring wells are recommended for installation in the mining district buffer zone <br />south and west of the Shiely high capacity well. The recommended wells should be <br />targeted for completion at the approximate depth of the nearby residential wells and <br />thereby monitor the primary groundwater zone used by the residential wells for possible <br />impacts resulting from use of the Shiely well. <br /> <br />According to the EIS (Table 3.3-1) most of the residential wells west of the District are <br />completed in the first confined glacial unit which occurs at a general elevation of 860 feet <br />NGVD. The well depths range from approximately 65 to 130 feet. Therefore, a monitoring <br />well installed to approximately the same elevation as these residential wells is <br />recommended for installation west of the pumping well. The attached figure provides a <br />general location for the recommended well. <br /> <br />. <br /> <br />A monitoring well is also recommended south of the Shiely well. The EIS indicates (Table <br />3.3-1) that the majority of the residential wells south of the mining district are completed <br />in the Mt. Simon - Hinckley Aquifer at depths of 230 to 400 feet. As such a Mt. Simon - <br />Hinckley monitoring well is recommended for installation near the general location <br />