9300 W MALL DR 2018-01-01 MF Import

; �-, Mr. C� �a� ��s Morga�, AIA 23 December 1fi93 �'age 2 supported entirely by local precipitation. '3urFace runoff ente�s the site from the east (west of the sidewalk), from the nortn (south of the existing drainageway), and from the we:st (both as sheet flow and frorti a culvert in the northwestern corner of the site). A review Qf the City of Everett':: draina� � maps revealed that the amount of drainage area above the site is about tr�ree times the area of the site itself, or about six times the area of impervious surface on-site. Consequently, if ai! precipitation collected on impervious surfaces were discharged off site there would he Ic .s than a 20°k reducti�}�; in runoff to ihe weflands. However, no collected stormwater would be discharged from the site. in fact, runuff from impervious surfaces on the site would be directed to the north end of the site via a bioswale and er•!er the head of the wetland system, thereby resulting in grr,ater hyc:rologicai support oi �ne wetlands folloH•ing project development. In c;n�er to miriic natural discharge of water into the w�3tlands, a dispersic,n trench wow� be u� ed at the outfall of both the northern and southeastern biosv�ales. Further�iore, Geotech Consult��ts, Inc. stated in their 3eoteohnical engineering stud�i (dated N,ovember 11, 19q3) that it was their opinion that the project would have no effect on the wetlands on the site due to the relatively impervious soil conditions located between the drains required for the basement and the wetland areas. Monitoring Plan A plan that monitc,rs the wetland F�ydrology and the wetland and buffer vegetation for a mini�um of three years is being prepared and will be submitted to the Planning Department for review and approval. If you have any questions regarding this letter, or if you would like further information, please call me at (206) 641-4710. Sincerely, TALASA CO l!!_TANTS � , � L� Wil iam . Shie PrinciFal cc: Mike Mastro, G&M Investments