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Groundwater -Surface Water Interaction and Wetland Impacts <br />A wetland delineation on the site was performed in October 2002 by North American <br />Wetland Engineering (NAWE) and reported in November 2002. The results of the <br />delineation were revised on March 14, 2003 after discussion with the WCA Technical <br />Evaluation Panel (TEP) convened to review the delineation. The final delineation is <br />reported in Appendix A and was discussed previously in Item 10. <br />Prior to performing the fieldwork, historical aerial photos were gathered from 1981-2001 <br />to evaluate the presence of potential wetland conditions through aerial photo <br />interpretation. Details and the photos are contained in Appendix A of this document. For <br />the time period of 1981 to 1989, the aerial photos show changes in the wetland hydrology <br />in and around the project site. Beginning about 1985, surface hydrology visibly <br />decreased in the flow -through wetland that runs from the northwest to the southwest of <br />the site. In addition, the large wetland located outside of and to the north of the site, <br />which in previous photos shows a large wetland with visible surficial hydrology, also <br />loses all signs of surface hydrology. In 1990, the hydrology of the wetlands begins to <br />recover until about 1997 when a similar pattern of surface hydrology losses occurs. As a <br />result, interpretation of the aerial photos suggest the presence of Type 1 (seasonally <br />flooded), Type 2 (wet meadow), Type 3 (shallow marsh), and Type 4 (inland deep marsh) <br />wetlands. <br />In 1997, several land use changes occurred in and around the RTC site. These include <br />the extension of County Road 116, the installation of three new municipal wells, and the <br />construction of a mitigation wetland in the northwest corner of the site. Both regulators <br />and local residents have questioned whether or not these land use changes where <br />responsible for the most recent observation of changes in wetland surface hydrology. <br />Due to the presence of a photographic record showing similar changes occurring prior to <br />the land use changes, it is not possible to tie the changes conclusively to any cause(s). <br />To address these concerns, the City of Ramsey is proposing to investigate this matter in <br />cooperation with the Anoka Conservation District, the Minnesota Department of Natural <br />Resources, and other resource agencies. The purpose of this collaboration is to determine <br />the effects of local groundwater interaction with wetlands, to monitor wetland hydrology <br />and to collect other pertinent information concurrent with the design phase." <br />Summary of Environmental Impact. <br />Wetlands Direct Impacts: Table 12.2 summarizes direct wetland impacts associated <br />with the RTC. A total of 6.94 acres of wetland impact will result from the RTC. A <br />break down of wetland types impacted is also shown. <br />12-4 <br />