1004 BROADWAY EVCC STUDENT HOUSING - PUBLIC WORKS 2017-01-13

Geotechnical Repart - Revised Pc�oposed Apartments: 1002, 1006, anc! 1008 Broadway Street, Everett, Washington May 12, 2015 • During wet weather, the allowable fines content of the stiuctural fill should be reduced to no more than 5 percent by weight based on the po�-tion passing the 0.75-inch sieve. The iines should be non-plastic. • The ground surface within the construction area should be graded to promote run-off of surface water and to prevent the ponding of water. • Geotextile silt fences should be installed at strategic locations around the site to control erosion and the movement of soil, • Excavation slopes and soils stockpiled on site shoufd be covered with plastic sheeting. 6.4 EROSION CONSIDERATIONS Surface �unoff can be controlled during constructian by careful grading practices. Typically, this includes the construction of shallow, upgrade perimeter ditches or low earihen berms in conjunction with silt fences to collect runofti and prevent water from entcring excavations or to prevent runoff from the construction area leaving the itmnediate work site. Temporary erosion control may require the use of hay bales on the downhill side of the project to prevent water from leaving the site and potential storm water detention to trap sand and silt before the water is discharged to a suitable outlet. All collecied water should be directed under control to a positive and pernnanent discharge system. Pennanent control of surface water should be incorporated in thc final grading design. Adequate surface gradients and drainage systems sliould be incorporated into the design such that surface runoff is collected and directed away from the stiucture to a suitable autlet. Potential issues associated with erosion may also be reduced by establishing vegetation within disturbed areas immediately following graciing operations. 7.0 ADDITIONAL SERVICES To eonfi�m that our recommendations are properly incorporated into the design and constniction of the proposed developrnent, PanGEO should be retained to conduct a review of the final pt•oject plans and specifications, and to monitor the construction of geotechnical elements. PanGEO can provide you a cost estimate for consti�aetion monitoring services at a later date. 15-Q4A 100�3 Broadway, Revised Page 15 PaI1GE0, Ine.