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Ken Meek (Earth Science Associates, Inc.) submitted a MN Joint Application on behalf of Len Pratt (CPDC Pratt Oakwood Ltd.) on April 27, 2018 requesting sequencing, sequencing flexibility, and wetland replacement for the Oneka Place Development; formerly Leroux Site. The application was considered complete on May 2, 2018. The applicant is proposing to develop 176 single family homes on the 120 acre parcel. A wetland boundary and type application was approved for the property on Januray 29, 2018. The approved wetland delineation report identified 26 wetland basins on the property. The most common type of wetland was type 2, but wetland types 1, 3, 5, and 7 were also identified in the report. Two separate groundwater investigations were completed to better understand the hydrology of the site and determine potential impacts to wetland hydrology from site devlopment. The first report titled "Geotechnical Evaluation Report, Leroux Property, Oneka Parkway and Ethan Trail, Hugo, MN" and dated May 16, 2017, reported findings from the installation of 16 borings throughout the parcel with most of the borings concentrating on the western 2/3 of the parcel. The results of this report indicate water elevations 0.1 to 4.9' below the ground surface with most of the 12 borings that were used in the report indicating observed water within 1' of the ground surface. One station showed "no water encountered". This report indicated that this was a perched layer of water and that the static water level was below this layer. The second report titled "Groundwater Investigation Report, Oneka Place, Hugo, MN 55038" and dated March 2018, reported findings from a separate study that utilized nine (9) observation wells to determine the static groundwater level. These wells were 24 to 35' deep. Results indicate that the static groundwater elevation ranged from 5.55 to 20.03' below grade, with an average of 13.25' below grade. Average groundwater elevation was 911.73'. Wetland bottom elevations range from 912 to 925.5' with an average bottom elevation of 918.57'. Based on these reports it appears wetland hydrology is driven by lateral movement of the perched groundwater and surface runoff within the individual contributing drainage areas (CDA), with minimal to no interaction between wetland hydrology and groundwater. Wetland to groundwater hydrology may be limited to acquifer recharge from downward flow of water from wetland basins to the acquifer. To further evalutae impacts to wetland basins from surface drainage alteration from development, a review of CDA volumes and rates were completed using P8 modeling. This analysis showed that existing surface hydrology to wetlands would be maintinaed with proposed development in both the 2 year and 100 year storm events. The applicant is proposing to permanantly impact eight (8) wetland basins from a combination of excavation and fill activities. These impacts total 0.91 acres. Sequencing Flexibility The applicant has requested sequencing flexibility for impacts to seven (7) of the wetland basins proposed to be impacted. This request is based on a MnRAM Functional Assessment of all wetland basins proposed to be impacted. Results of the analysis showed that 7 of the 8 wetland basins are classified as manage 3; with most wetland functions described as low. Wetland L was classified as a Preserve and it is not included in the request for sequencing flexibility. The 7 wetland basins for which sequencing flexibility is being requested (basins B, BB, D, E, F, I, and P) mainly consist of reed canary grass and meet the requirements described under MN Rule 8420.0520 subp. 7a. BWSR Forms 11-25-09 Page 2 of 6