6600 MERRILL CREEK PKY BLDG A SHELL 2016-01-01 MF Import

Remove standing water Crom the excavation area. Outfall water should be filtered or run through a sedimentation basin. Use surface crosion measures in areas in which surface water is anticipated to drain from the excavation area. Require control measures to be designed by a professional civil or geotechnical engineer, to prevent ofC:ite surface drainage of sediments. Methods may include, but are not limited to, use of'silt ferces and/or settlement ponds. hnplement a plan to minimize the extent to which these soils become disturbed. Soils which become disturbed, and �vhich are above their optimum moisture content, should either be allowcd to dry to within Qieir optimum moisture content and be re-co:npacted, or be removed from the construction site. (SEPA Eartl� and Water Policies) 3. Any watrr quality enhancement or detention facilities proposed near steep slopes will require detailed geotechnical analysis and design that documents and ensures their safery. (SEPA Earth and Water Policics) 4. Prior to issuance of grading permits for removing earth from a site, the applicant must demonstrate that permits have been obtained for placement ofthe earth off-site. (SEPA Earth and Water Policies) During Construclion/Earthwork 5. All earthwork within a geologically hazardous area or its required buffer must be perfomied under the supervision of a professional civil or geotechnical engineer. The engineer must provide certification to the Ciry that all work was done in compliance with requirements set forth in the Ciry approved geotechnical report. (SEPA Earth and Watcr Policies) G. In order to minimize erosion during construction, all soil piles shall be covered with plastic sheeting or other impervious covering staked to the ground or anchored with rocks or sandbags. Berms, earthen or othenvise, must be constructed at the perimeter of excavated areas to prevent adjacent site runoff from entering the excavations. (SEPA Earth and Water Policies) 7. Temporary slopes within native glacial soils shall be limited to a maximum angle of 1/2 foot horizontal (H) to 1-foo[veriical (V). Temporary slopes within fill soils shall be limited to a maximum angle of l H:1 V. Temporary slopes must be covered with an impermeable memLranc, such as visqueen or mulch, in order to prevent precipitation from coming in contact with the soils. (SEPA Earth and Water Policies) Pennanent slopes steeper than 25% shall be designed by a professional civil or geotechnical enginecr. The design should present appropriate erosion control measures which may include hydrosecding, erosion control blankets, rip-rap,jute matting, and visqueen. (SEPA Earth and Water Policies) 8. Grading/filling must not adversely afT'ect the hydrology of strcams and existing or created wetlands. (SEPA Earth and Water Policics) �