17 E MARINE VIEW DR 2019 Geotech Report 2025-10-01

Drainage Considerations We recommend that all surfaces be sloped to drain away from the proposed structures.Pavement surfaces and open space areas should be sloped such that the surface water is collected and routed to suitable discharge points. As discussed previously, the large stockpiles will result in settlement beneath and surrounding the area of the stockpiles. Site grading for drainage should include provisions for this anticipated settlement. Based on the soil conditions observed in the explorations, we anticipate that groundwater in temporary shallow excavations can be controlled by pumping water from shallow sumps.The contractor should have the responsibility to determine what dewatering measures are needed. Site Preparation and Earthwork We recommend that site preparation and earthwork be completed during the normally dry season of the year(generally July through September)if practical,as the workability of the soil becomes difficult and the erosion potential of the onsite soils is increased during extend periods of wet weather. Erosion and Sedimentation Control Potential sources or causes of erosion and sedimentation depend upon construction methods,slope length and gradient, amount of soil exposed and/or disturbed, soil type, construction sequencing and weather. The project impact on erosion-prone areas can be reduced by implementing an erosion and sedimentation control plan. The plan should be designed in accordance with the City of Everett and/or applicable Snohomish County standards.The plan should incorporate basic planning principles including: ■ scheduling grading and construction to minimize soil exposure, ■ retaining existing vegetation whenever feasible, ■ revegetating or mulching denuded areas, ■ directing runoff away from denuded areas, ■ minimizing the length and steepness of slopes with exposed soils, ■ decreasing runoff velocities, ■ preparing drainage ways and outlets to handle concentrated or increased runoff, ■ confining sediment to the project site,and ■ inspecting and maintaining control measures frequently. Temporary erosion protection should be used and maintained in areas with exposed or disturbed soils to help minimize erosion and reduce transport of sediment to adjacent areas and receiving waters.Permanent erosion protection should be provided by re-establishing vegetation by hydroseeding or landscape planting. Until the permanent erosion protection is established and the site is stabilized, site monitoring should be performed by qualified personnel to evaluate the effectiveness of the erosion control measures and repair and/or modify them as appropriate. Provisions for modifications to the erosion control system based on monitoring observations should be included in the erosion and sedimentation control plan. GEOENGINEERS� August 3,2018 Page 12 File No.0043-015-00