3611 FEDERAL AVE 2018-01-02 MF Import

Geologic Investigation and Geotechnical Fngineering Report Jones Residence 3611 Federal Ave. Everett, Washington 98-08-10 backfilled with a minimum 18" or 5/8" minus washed pea gravel. Downspouts and yard drains should be tied into their own minimum 4" diameter ADS drain line placed in such a manner as to allow for positive flow of water through the drain line toward an appropriate point of discharge. Cleanouts should be provided along all drain lines in locations that allow ease of maintenance and operations. The site soils are not conducive to on -site storm water retention. Permeability of the underlying silts is not high enough to provide adequate percolation of collected storm water. We recommend that collected storm water be treated in the same manner as run-off has been controlled historically on the site. Collected storm and drainage water should be discharge at an appropriate point on or immediately below the site in such a manner so as to direct the water away from any site improvements and not to degrade slopes down gradient of the site. Discharge should occur in a controlled manner so as to limit erosion potentials at the discharge point. 4.10 Erosion Control Measures Best Management Practices (BAV s), as outlined in the Washington State Department of Ecology's Storm {Pater Management Manual for the Puget .Sound Basin should be applied during the construction phase of this project. Erosion control measures should also comply with WSDOT Standard Specification section 8-01, Erosion ('orttrol. Due to the proximity and steepness of the site slopes, filter fences and straw bale filters should be placed along all construction limits at the set back limit to help control siltation off site during construction. Grading of the construction site should be completed such that drainage within the construction area flows through siltation fences and bioswale buffers Any identified surface drainage pathways off of the site should be protected from run-off and siltation with filter fences, straw bales or settling ponds. Permanent erosion control measures should be installed as soon as possible after the completion of work in any one area. 15 . GES, Inc.