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staff comment and applicant responseTree removal is shown outside the limit of work line within the riverfront. The limit of work should be adjusted to include proposed areas of vegetation removal. Revised plansheets submitted Organic piles and cleared areas presented as 'existing degraded' do not meet the requirements to be considered previously disturbed or degraded pursuant to 310 CMR 10.58 (5). These are limited to "areas degraded prior to August 7, 1996 by impervious surfaces from existing structures or pavement, absence of topsoil, junkyards, or abandoned dumping grounds." and must be removed from the calculations. Revised calculations and plansheets which remove all areas identified in the photo sheets from being classified as degraded from both riverfront and buffer area Regarding the house work at the upper site, the application discusses improvements related to stormwater in the lower wetland, but doesn't specifically address the new buffer zone work related to the house. The Ordinance requires that the "applicant must provide evidence deemed sufficient by the Commission that the area being disturbed will not harm the resource area values protected by the law." Could you provide a narrative as to how this standard is met? Locating the house and related improvements outside buffer areas except where previous degraded areas existed will be an option the Commission will ask about. The existing house sits at the top of the upland plateau within the outer 50’-100’ buffer zone and the existing configuration of the drive and house make vehicular circulation challenging. The existing house and driveway contribute stormwater directly into a riprap swale to the east of the drive which outfalls to the street within the Riverfront Area. The property owners were attracted to the site because of the location on the outskirts of Northampton and the wooded character of the 40.3 acre lot and neighborhood. When considering locations on the property to site a new home, a house further to the rear of the upland plateau would afford various environmental, safety and sustainability benefits, including: • the project space to accommodate turning movements of safety vehicles, • the ability to manage stormwater runoff more effectively on site, and • preservation of the wooded character of the neighborhood (e.g., along Turkey Hill Road as well as further upland on the other 38 acres of the site). Within the Upland Plateau, the majority of the house/driveway work takes place outside the 100’ Wetland Buffer. The proposed work taking placing within the 0’- 100’ buffer of the upland plateau takes place today on previously developed areas: which include an existing drive, existing house, existing sheds, existing lawn and landscaped areas. The existing drive crosses into the 0’-50’ buffer zone and serves as a rough ridge line on the plateau. Rain water falling upon existing drive slopes towards the existing house and existing drive towards points north away from the wetland. Water falling to the south is directed towards the existing wetland and to points further southeast of the project area. There is little to no existing stormwater management on site. The roof water sheet flows directly into a riprap swale along the driveway and outfalling into the street. The wetlands to the west of the upland plateau intercept stormwater runoff coming from a westerly slope before running to the south into a larger wetland feature. The proposed plan takes this natural flow condition into consideration, while protecting the resource area from negative impacts of proposed impervious surfaces. Stormwater falling on impervious surfaces within the Outer 50’- 100’ wetland buffer zone, is directed away from the wetland area. Water falling on the roof, including the portion of the roof within the outer 50’-100’ buffer zone is collected via gutters and downspouts and subsurface piping to a subsurface infiltration system to the east of the house. This system allows water to infiltrate into the ground below. An emergency outfall is provided for any storms greater than the 100 year event and is located downslope of this area, and directed away from an adjacent abutter’s house. The level spreader prevents erosion by implementing level structure which will dissipate flows. The system is sized to hold and infiltrate a 100’ year storm. For more information about storm capacity and system components, please refer to the full stormwater report prepared for the project. Similarly, rainwater falling upon the emergency vehicle turnaround and portion of the driveway which is located in the outer 50’ to 100’ wetland buffer, is directed into two storm basins on the north side of the drive to improve water quality and manage up to 100 year storm events. Together these two strategies ensure that the wetlands will be protected from runoff from these surfaces during heavy events. In addition, the project does not have a negative impact on downstream flooding, as it results in no net increase of stormwater runoff in a 100 year storm. In addition, the project adds a bioretention area at the bottom of the drive to help improve water quality for any water leaving the site. The project area does not contain any rare species habitats according to Oliver GIS’s online map viewer. The project retains the majority of the project parcel (40.3 acres as wooded areas and walking trails) providing wooded habitat and habitat for edge species flora and fauna. There are areas within the 0-50 foot zone that are proposed to be disturbed during construction, then loamed and seeded and used as a lawn area not previously permitted, how does this meet the performance standards of the Ordinance? Per the recommendation of the arborist, the project is proposing to remove dead and or diseased trees adjacent to the immediate project area which might pose a safety risk due to structural issues. Some of these trees fall within the inner wetland buffer of 0’-50’ and one tree, tree #1652 is within the wetland area itself. It is not the intent of the client to add these as lawn areas, but instead to stabilize them and allow them to transition back to forest edge over time. The plan currently calls for an upland sedge mix at the edges, but the project defers to the Commission to direct the best way to address these issues. The project is willing to entertain alternative ways of addressing these trees with the Conservation Commission so as to minimize the disturbance to the buffer zone.