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photography analysis showed that for the period 1981 though 1996, the acreage of <br />wetlands remained fairly constant. Beginning in 1997, however, the acreage of wetlands <br />visible on the aerial photography declined sharply. With this decline, the area of <br />wetlands visible on aerial photos became progressively smaller each year. Since this <br />decline, wetland hydrology (as defined by water pooling on the surface) has not returned <br />to pre-1997 levels, in spite of the fact that in recent years, northwestern Anoka County <br />has received normal levels of annual precipitation. Both 2000 and 2002 were determined <br />by the State Office of Climatology to be normal precipitation years. An on -site <br />assessment of wetland hydrology and vegetation completed as part of the wetland <br />delineation concurs with the aerial photography analysis. <br />A groundwater elevation and soils study was conducted by Braun Intertec in January <br />2003 to evaluate if the wetlands were influenced by groundwater. Results of the study <br />indicated the wetlands at and adjacent to the site are groundwater dependent and directly <br />linked to the regional groundwater system. The study showed that wetland hydrology is <br />not linked to localized conditions, such as impermeable clay lenses that function to <br />—perch" the wetlands above the water table. <br />There are several land use changes and other activities that might have had an impact on <br />the regional groundwater system. In 1997, County Road 116 (including wetland B) was <br />constructed along the north side of the RTC site. It is possible that this road construction <br />interrupted groundwater flows; however, wetlands both up -gradient and down -gradient of <br />the County Road 116 (with respect to ground water flow direction), appear to be <br />impacted. The City of Ramsey also installed two new municipal wells (Wells No. 3 and <br />4) along the north side of the County Road 116. Because there are no data linking <br />iuuiidwater pumping to surface water response, these mew" land uses cannot be <br />conclusively proven to have caused the changes in hydrology. It is, however, evident that <br />the groundwater influence, wherever it may come from, on the wetlands has changed. <br />Additional data on the influence of land uses and groundwater appropriations is needed to <br />conclusively determine if these activities are impacting groundwater -dependent wetlands. <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 />