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4735 Bayview Lane <br />Everett, Washington Geotechnical Report <br />should not extend within 12 inches of the surface but should be capped with more impermeable <br />soils such that surface water does not freely enter the drainage layer. The drainage material must <br />hydraulically connect to the footing drain system. <br />Drainage <br />Storm water from impermeable surfaces should be collected and discharged into a city approved <br />storm water drainage system. Based on the soils encountered on the site it is our understanding <br />that the project civil engineer, Omega Engineering, is recommending downspout dispersion for <br />the project. Downspout dispersion systems can be utilized but we recommend that the surficial <br />soils be amended as per the civil plans in order to provide additional absorption capacity <br />Footing drains should be placed around all old and new foundations. We also recommend that <br />existing footing drains, if present, should be removed and replaced or at a minimum thoroughly <br />cleaned and verified as old drains are likely full of roots and sediment and no longer working <br />efficiently. Footing drains should consist of 4-inch diameter, perforated, pvc pipe that is fully <br />covered with clean drain rock and the entire system wrapped in geotextile filter fabric. The <br />perforations should be placed such that they are in the lower quadrant (approximately 5 and 7 <br />o'clock positions) of the pipe. The pipe should be placed at the bottom of the footing and be sloped <br />to gravity drain. <br />Under no circumstances should any collected storm water be discharged over the top of the steep <br />slope area. <br />Erosion <br />Suitable best management practice (BMP) erosion control measures should be implemented for <br />the project. A silt fence should be placed around the perimeter of the construction area. Soil <br />stockpiles should be covered with plastic sheeting to contain in -situ moisture and prevent storm <br />water runoff. All excavated soil that is not used for foundation backfill purposes should be <br />removed from the site. Under no circumstances should any fill soils be placed on or near any of <br />the steeply sloping areas of the site. Areas of disturbance should be limited to necessary <br />construction areas. A rocked construction entrance will not be necessary as the existing gravel <br />driveway will be utilized for a staging area. <br />Summary <br />Construction monitoring and consultation services should be provided in order to verify that <br />subsurface conditions are consistent throughout the project area and will provide suitable bearing <br />for the new footings. Other construction monitoring activities may be required by city staff. <br />Gary A. Flowers, PLLC <br />5205 23' Avenue W Everett, Washington 98203 206-819-4304 <br />7 <br />