2219 PINEHURST AVE BASE FILE 2020-07-14

Stormwater Pollution Prevention Plan 2.0 Site Description 2.1 Existing Conditions The current parcel is 8,941 s.f.; the proposed duplex lot is covered with soil and gravel, with some grass. There are no trees or shrubs. There is an existing garage that will be demolished as a part of the proposed construction of a new garage and driveway for the adjacent existing house. There are no wetland and/or associated buffers located on the Proposed Lot. The proposed lot boarders and takes access from Pinehurst Avenue along the south property line, and boarders other adjacent parcels along the west, north and east property lines. The roof run-off of the proposed house will be connected to downspouts to cleanouts and then tight lined to the existing combined sanitary sewer/Stormwater system. As per the WSDOE Stormwater management manual, the project is required to infiltrate or disperse Stormwater whenever possible. As the site has glacial till soils, and hardpan at an average depth of 32 inches, and very limited flowpath lengths, infiltration and dispersion is simply not feasible and would not work. The area of the proposed roof is 2632 SF. The additional 1043 sf of PGIS area (proposed driveway) will be allowed to sheet flow to the south into Pinehurst Avenue. Per the United States Department of Agriculture NRCS Web Soil Survey, site soils are Alderwood Urban Land Complex, 2 to 8 percent slopes. Test pits excavated on the property for the drainage design for the proposed residence are consistent with this soil type. Soil investigations indicate depth to restrictive feature: 28 to 39 inches to cemented horizon; 20 to 39 inches to densic material. The Natural drainage class is poorly drained. The depth to the water table is about 18 to 36-inches. The interpretive Hydrologic Soil Group is C. 2.2 Proposed Construction Activities The Pinehurst Ave Duplex project proposes the construction of one Duplex Structure on 3 existing lots in central the City of Everett. The project is located at 2215 Pinehurst Avenue, Everett, WA 98503 0, in the SW 1/4, of the SW 1/4 of Section 5, Township 28N., Range 5 E., W.M. in The City of Everett. More specifically, the project occupies The City of Everett tax lot number 00544701002900. Construction activities will include site preparation, TESC installation, grading, and excavation for the proposed structure. Temporary sedimentation facilities will be provided on the site during detention system construction to assure flow rates are controlled, although a summer construction schedule does not expect elevated rainfall volumes. The following table summarizes details regarding site areas 5