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  <br />provide a plan to protect adjacent wetlands, the plan shall also include a mitigation plan if <br />the wetlands are impacted post construction. <br />With regards to pond construction and potential drainage effects on adjacent wetlands: <br />  <br />• Pond 300 in the northeast portion of the development area will be a maximum of 22 feet <br />deep, has a predicted NWL of 902-ft, and has no outlet (no outlet structure or emergency <br />overflow). In reality, the open water portion of Pond 200 will be the elevation of the local <br />water table and will vary throughout the year as the water table does because the pond <br />does not have a controlled outlet to stabilize water levels. Because the pond does not <br />have an outlet to drawn water down, it will not drain nearby wetlands (there is no where <br />to drain the water if there is no outlet). For these reasons, drainage effects to Wetlands 3, <br />3a, or 3b from Pond 200 construction are not expected to occur. A similar pond with no <br />outlet was constructed onsite sometime after 1991 near the proposed wetland banking <br />wetland. That large, deep, open-water pond was excavated adjacent to wetland and has <br /> <br />not resulted in wetland drainage. <br />  <br />• Pond 200 will be excavated in around the west end of ACD 10-22-32 (west of the current <br />ditch crossing). The ditch currently drains freely to the west (no controlled outlet). Water <br />levels in the ditch were measured at 901.5-feet by the engineer. Therefore, newly <br />constructed Pond 200 will have an OSC with V notch weir invert of 901.5-ft with the top <br />of the weir at 902.5-ft. The adjacent wetland the southeast (Wetland 2) will have a NWL <br />of 902.0-ft, and will have a raised outlet (EOF only) at 902.5-ft. Wetland 2 will need to <br />be inundated with over 6 inches of water to outlet to Pond 200. That occurrence alone, <br />usually occurring early in the growing season, will meet wetland hydrology <br />requirements. For the remainder of the growing season, Pond 200 and adjacent Wetland <br />2 water levels will fluctuate with precipitation events and normal seasonal water table <br />level variations. For these reasons, drainage effects to Wetland 2 from Pond 200 <br />construction are not expected to occur. <br />  <br />• Wetland 4 to the northwest of Pond 200 will not have an outlet, will not be connected to <br />Pond 200, and will be physically separated by the pond maintenance bench/berm. For <br />these reasons, drainage effects to Wetland 4 from Pond 200 construction are not <br />expected to occur. <br />  <br />• The current and proposed ditch crossing culvert invert elevations and size are equal pre <br />and post development. Therefore, drainage effects to upstream wetlands are not expected <br />to occur. <br />  <br />Per Kjolhaug Environmental Services <br />  <br />Applicant is submitting a geotechnical report addressing the existing wetland & soil <br />conditions and present any proposals to protect the adjacent wetlands as needed. <br />See attached Wetland permit application. Geotechnical report to be submitted when <br />received. <br />  <br />4.A review of the DNR’s Natural Heritage Information System (NHIS) Database revealed <br />that rare features have been recorded in or near the wetlands on the property. In 2002, <br />toothcup (Rotala ramosior), a state threatened species, was located within one wetland