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Well House No. 7 Feasibility Study <br />City of Lino Lakes, MN <br />WSB Project No. 013434-000 Page 5 <br />3.1.5 TEST PUMPING RESULTS <br />During the test pumping of Test Well No. 7, water levels were monitored in Lino Lakes Municipal <br />Well No. 2, the adjacent failed test well, and a nearby private well. Well No. 2 is constructed in <br />the Jordan formation, the adjacent failed test well is a Prairie du Chien well, and the private well is <br />constructed in the glacial drift. During the pumping of Test Well No. 7, there were no influences <br />observed in Well No. 2 or the private well. Drawdown results are provided in Appendix B. <br />Locations of the wells monitored during the test pumping are shown in Figure 2 <br />Further investigation of the City’s well field was completed as a part of this study and consisted of <br />using the City’s existing groundwater model to determine the impacts to the City’s drinking water <br />supply management area (DWSMA). The model was updated with existing Well No. 6 and <br />proposed Well No. 7. For Well No. 6 and Well No. 7, pumping rates of 1,200 and 1,000 gpm, <br />respectively, were applied to the model. The results of this modeling exercise resulted in the <br />expansion of the City’s DWMSA in the south/southwest portion near existing Well No. 6 and <br />proposed Well No. 7, as shown in Figure 3. <br />3.1.6 CONCLUSION AND FUTURE MUNICIPAL WELL CONSTRUCTION <br />RECOMMENDATIONS <br />Based on the site conditions and test well results, an open hole Jordan aquifer well at this site <br />appears to be feasible and should be capable of producing a pumping capacity near 1,000 gpm. <br />Using the assumed pumping rate of the 1,000 gpm, the boundary of the DWSMA is expected to <br />expand to the south/southwest. The DWSMA boundary is an estimation, as the City’s existing <br />model would need to be updated with additional information from MDH models to accurately <br />regenerate a new Wellhead Protection Area (WHPA) boundary. WHPA boundaries are analyzed <br />in conjunction with property and natural boundaries to regenerate DWSMA boundaries. Lastly, <br />the City’s groundwater model was used with estimated pumping rates, that may change during <br />future system operations. <br />If the City decides to construct a future municipal well at this site, the resulting recommendations <br />are as follows: <br />Submit an appropriations permit amendment request to the DNR. <br />Confirm with the DNR that the conversion of Test Well No. 7 into a Jordan observation <br />well will not be required. <br />The proposed Municipal Well No. 7 should be bid as an open hole well but with a bid <br />alternate to be constructed as a screened well, if deemed necessary during construction, <br />due to the observed changes in geology. <br />Work with MDH during the amendment of the City’s WHPP Part 1 to better understand <br />the changes the City’s DWSMA, associated aquifer vulnerabilities, and interactions with <br />the addition of existing and proposed wells.