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<br />City of New Brighton is currently using the Mount-Simon Hinckley Aquifer to supply its <br />water system. <br /> <br />Description <br />The Mount -Simon Hinckley Aquifer is the deepest bedrock formation in the Twin Cities <br />and at a significantly deeper depth than the Jordan Aquifer. This aquifer is confined and <br />less suscept ible to surficial contaminants such as Dioxane that exists in the Jordan <br />Aquifer. Options were analyzed to convert the existing wells into deeper Mount-Simon <br />Hinckley wells or drill new wells into the Mount-Simon Hinckley Aquifer. <br /> <br />New Mount-Simon Hinckley wells can potentially be drilled although it is very <br />uncommon for the DNR to approve them. The State of Minnesota currently has a <br />moratorium that restricts the use of the Mount -Simon Hinckley Aquifer in the Twin <br />Cities Metropolita n Area. Therefore, the DNR does not issue appropriation permits to <br />cities to pump groundwater from this aquifer. <br /> <br />The City would be required to receive a variance from the DNR before this option could <br />be fully analyzed. There is no guarantee that the DNR would issue a variance for these <br />wells to St. Anthony Village. Variances are provided only when no other water supply <br />options exist for a public water system. <br /> <br />Well No. 4 in St. Anthony Village cannot be converted into a deeper Mount-Simon <br />Hinckley well because a 10-inch casing would need to be installed inside the existing 18- <br />inch casing to comply with the Minnesota Well Code. The 10-inch casing would not <br />allow a large enough well pump to be installed inside the well to produce the needed <br />capacity to make this option feasible. Well Nos. 3 and 5 could potentially be converted <br />to Mount-Simon Hinckley wells; however, this option is not cost effective since it would <br />require the open hole at that base of the existing Jordan wells to be completely grouted. <br />This is very costly and difficult from a constructability standpoint. <br /> <br />Advantages <br />This option would provide the following advantages: <br /> <br />1. The Mount Simon-Hinckley Aquifer does not contain any known concentrations <br />of TCE or Dioxane. <br /> <br />2. The Mount -Simon Hinckley Aquifer is better confined and protected from other <br />potential contaminants or sources of surface contamination compared to the upper <br />aquifers (Jordan Aquifer , etc.). <br /> <br />3. The City of St. Anthony would maintain control of its water production and water <br />rates. <br /> <br />Disadvantages <br />This option would provide the following disadvantages: <br /> <br /> <br />1,4-DIOXANE PROJECT <br />FEASIBILITY REPORT <br />CITY OF ST. ANTHONY VILLAGE <br />WSB PROJECT NO. 3183-00 PAGE 7