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Camposeo_2022_Project_Narrative_Revised_7_5_22 (1).pdf2.00 PROJECT DESCRIPTION The items contained in the following sections supplement, as noted, the Project Description Narrative submitted with the 2019 Notice of Intent. 2.10 Description of Amended Plan — Supplement to § 1.1 of 2019 Project Description Narrative The current proposed Plan (4/10/22) relocates the driveway approximately 8 feet south of the location approved in the 2019 Plan (6/3/19). With earthen fill side slopes, the horizontal reach of the wetland disturbance footprint varies, to meet the underlying existing terrain. In some places the horizontal extent of disturbance is wider than proposed in 2019, while in other places the horizontal extent of disturbance is narrower than in the 2019 Plan. The net result is an overall decrease of 158 s.f. in wetland disturbance by utilizing earthen fill for the edges of the driveway. The following Table summarizes the extents of wetland disturbances in three areas of the driveway, comparing the areas disturbed in the 2019 Plan to the areas disturbed in the currently proposed 2022 Plan. Plan date (Year) West Disturbance (s.f.) Middle Disturbance (s.f.) East Disturbance (s.f.) TOTALS (s.f.) 2019 666 1,518 2,222 4,406 2022 661 1,640 1,947 4,248 CHANGE: (-5) +122 (-275) (-158 s.f.) We are forwarding an electronic version of the plan which shows the areas of wetland disturbance polygons. The polygon areas coincide with the square footage numbers reported on the Plan view. 2.20 Wetland Mitigation Measures Supplement to § 1.5 of 2019 Project Description Narrative 2.21 Erosion Control Driveway Side Slopes — Construction Materials The side slopes on each side of the proposed driveway repose at a slope of 1.75' :1' (horizontal:vertical). Due to the flatness of the underlying terrain, the modest horizontal extents of earthen side slopes range in width on each side from 1.7' to 3.5.' The finished grades are not higher than 3 feet above existing grade at any point where the driveway crosses wetland. In most places, the finished grades are only 2 feet higher than existing grades. In the 2022 Plan, the earthen side slopes stabilization is enhanced with the permanent placement of 2" crushed stone for a depth of 4", over the entire side slope. In addition, filter fabric will be placed on top of the prepared earthen side slope and under the 2" crushed stone. Filter fabric keeps the crushed stone from mixing with the underlying imported soil. Filter fabric also helps keep the crushed stone in place as the underlying soil settles after placement and compaction. Once in place, the crushed stone will minimize side slope erosion. As with the earlier approved plan, a silt fence would be used for erosion control during construction. Pre-Construction The limit of work follows the furthest lateral extent of the finished grade(s) (lowest elevation). The enclosed version of the Plan is produced in color, with additional notes to provide clear direction to the excavation contractor. The lowest finished grade elevations/silt fence lines are depicted by a red line. Prior to the commencement of work, the horizontal extents of silt fence/finished grade will be pre- marked on the ground by the registered land surveyor. The construction contractor will install the silt fence along the surveyor's pre-marked lines. This precise approach enables the erosion control to be established without following parallel lines. Silt fence will be continuous. Silt fence will be installed in between any gaps between plan drawn finished grade lines. Post Construction When driveway construction is complete, the silt fence will be removed. The finished sides will remain intact. Three characteristics of the side slopes will prevent future soil erosion. • Light compaction of imported side slope soil • Placement of filter fabric over the imported soil, and under the crushed stone • Placement of the 2" crushed stone over the filter fabric. [See letter of George Costa, P.E. dated 7/5/22 characterizing side slope stability.] 2.22 Wetland Replication Area Amends § 1.51 of 2019 Project Description Narrative The configuration of the wetland replication area is fundamentally the same in this proposed 2022 Plan as it was in the 2019 approved Plan at a 1:1 ratio. For the 2022 Plan, the amount of wetland disturbed is 4,248 s.f. and the wetland replication design area is slightly larger at 4,337 s.f. In the 2019 Plan, the amount of wetland disturbed was 4,406 s.f. and the wetland replication area was exactly equal at 4,406 s.f.