Agenda - Council - 05/27/2003 - Laserfiche WebLink

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and its water supply potential in the northwestern part of the Twin Cities Metropolitan Arca (Chris Elwum at the Met Council, 651-602-1066). Understanding the system clynamics oFthe FiG locally and regionally will help the City respond to (and perhaps avoid) complaints about its municipal pumping interfering with other local resources such as private wells and surface water bodies. Response: The City acknowledges the differences in the FIG within the region and is committed to undertaking the study identified in the AUAR to further its knowledge of the FIG behavior locally. The City will follow the progress of the MGS/Met Council study and will cooperate to the extent possible with all of the agencies involved in researching and regulating use of the FIG. The City recognizes the need to provide observation wells in the glacial aquifer and the need to perform botln a pump test and long term trending analysis. It also concurs with the observation that the local transmissivities observed in Municipal Wells No. 3 and 4 are probably not representative of average conditions with the FIG. As a result, a more extensive hydrogeologic investigation of the Io¢a~l lrlG capacity is planned prior to installation of additional wells. Comment 13.2: I would encourage the recommendation made on pages 13-7 and 13-8 (as well as Appendix F) that one or more nests of monitoring wells be placed in the area around the well filed to monitor water level changes in the glacial materials over time. I might also suggest that, if these wells were to be placed, a pumping test could be peribrmed using one of the city's existing wells. Such a test would establish the nature of the hydraulic connection between the bedrock and the (surficial) drift and could probably be accomplished at little cost to the City. MDH staff and equipment are available to assist with such an eft:oft because the results could be used to refine the wellhead protection planning el'[brts of the City. In the end, the kind of data generated from long term monitoring and fi'om pumping tests will be of greater value in establishing the el'l. Ect, if any, of municipal pumping on groundwater elevations in the area than just about ~lny other kind o[~data or analysis. Response: The City acknowledges the comlnents and will incorporate them into its monitoring program as it develops. The offer of staff and equipment assistance is gratefully acknowledged, and will be considered as well. .~4-_7 -175-