10200 19TH AVE SE COSTCO FUEL STATION 2016-01-01 MF Import

n'� � �� Earth Consultants Inc. �IIII I , (��IvIlpMiIII'11RI1N•Yfti.GOMryjL•1tihIJ1\lt�M1ONY11lIYI1TIR�5 I January 13, 1999 E-8556 Costco Wholesale c/o Barghausen Consulting Engineers 18215 - 72"d Avenue South Kent, Washington 98032 Attention: Mr. Jay Grubb Dear Mr. Grubb: We are pleased to submii our report titled "Geotechnical Engineering Study, Proposed Costco Retail Gasoline Facility, 10200 - 19"' Avenue Southeast, Everett, Washington." This report presents the results of our field exploration, selective laboratory tests, and engineering analyses. The purposc and scope of our study was outlined i�� our November 30, 1958 proposal. In our opinion, development of the site as planned is feasible from a geotechnical standpoint. The critical geotechnical issues to be addressed are primarily related to foundation support for the proposed freestanding fueling canopy and controller enclosure, and providing a stable excavation for the proposed underground storage tanks. In our opinion, the proposed fueling canopy can be supported on conventional spread and continuous footings bearing on the competent native soils underlying the fill or on structural fill. The existing silty sand with gravei fill can be considered for use as structural fill, provided the fili can be compacted to the specifications of structural fill described in this report. The native soils should provide adequate support for the proposed underground storage tanks. We do not anticipate groundwater seepage will present major problems in the tank excavations. ��commendations for foundation support, excavations, and controlling groundwaterseepage, if encountered, are presented in the following sections of this report. 1805- 1361h Place tJ.E..Sui(e 2D1,Bellevue,Nlashing(on 98005 Believue�425)643-3?80 FAX(425)74fi-0860 Toll Free(888)739�66i0 O