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COR Wetland Mitigation Memorandum October 7, 2021 Page 2 Under the rules in place at the time of permitting (pre-2015 WCA revisions), wetland mitigation included two basic components: New Wetland Credit(NWC)for the creation or restoration of wetland and a companion Public Value Credit(PVC)component which considered areas of storm water pond treatment and upland buffer. These components were measured by square feet, with 100% of the area determining the crediting for features. Both mitigation sites have proposed a combination of NWC and PVC. Performance standards under previous iterations of the WCA were less specific than current standards. While some sites could have an agreed upon site-specific standard, most mitigation sites were expected to be dominated by native vegetation and have a minimum number of native species present. Based on the 2011-2012 monitoring reports, the sites did not meet performance standards, and extensive work was completed to improve vegetation quality from what had developed since 2006 without any maintenance. This restoration work included herbicide applications to remove all vegetation, followed by reseeding and planting of plugs. In essence, the vegetation of the site was reset with these activities. Wetland Mitigation Goals The goal of the project is to create 70,816 ft2 of wetland (NWC), and 78,818 ft2 of Public Value Credit (PVC)through the creation of two wetland mitigation sites: Charter School Wetland and Northwest Wetland (Figure 1). A summary of the wetland mitigation area goals based on the requirements identified in the 2011 and 2012 monitoring reports is provided in Table 2. Table 2: Summary of Wetland Mitigation Goals Feature and Location Credit Type Proposed (square feet) Charter Site New Wetland NWC 24,816 Stormwater Pond and Buffer PVC 321818 Subtotal 57,634 Northwest Site New Wetland NWC 46,000 Stormwater Pond and Buffer PVC 46,000 Subtotal 92,000 Total 149,634 The 2011/2012 wetland monitoring reports discuss that the two sites appeared to generally follow the approved construction plans, but additional wetland habitat was present beyond what was anticipated. This may be from minor deviation from construction or a result of more than expected hydrology following construction. It was noted in the monitoring report that more wetland was present than proposed, but appeared to result from natural expansion of the wetland area and not from over-excavation by contractors. The 2011/2012 wetland monitoring reports also provided better precision on the proposed areas of wetland and associated features. These appear to be based on GIS-derived as-builts of the two areas, and an estimate of what is anticipated based on the conditions present at the time. This includes an estimate of wetland communities and more details on the areas of the pond and surrounding upland buffer. The as-built analysis indicates that the Charter Wetland is essentially constructed as proposed, while the Northwest Wetland appears to have been graded to create more wetland than initially proposed. The total area planned is unchanged (149,634 ft2), however the total actual area present (152,634 ft2) is larger by