1011 39TH ST 2016-01-01 MF Import

GEOTECHNICAL ENGINEERING STUDY Susan and Tliomas Zakos E-10138 August 20, 2002 Page 5 DISCUSSION AND RECOMMENDATIONS General Besed nn our subsuriace exploration, the backyard area along the existing wall alignment is underla�r� by up to eight feet ot very loose to loose fill and native soil. As su�h, the wall and deck supports are likely foundecl in the very loose to loose fill or native soils. In our opinion, the rotation of the retaining wa!I and deck supports is likely a result o( settlement and gradual dow;�slope creep of tlie existing fill and underlying surficial native soils. At the time of our study, the foundation of the residence showed no indications of pronounced cracking or offset and does not appear to be settling. In our opinion, the existing residence is not at risk in its present condition, ancl no remedial foundation or stabilization measures are recommended at this time. However, continued movement and settlement oi the fills north of tlie residence could compromise foundation support of the residence. In our opinion, the very loose to loose fill and native soil encountered on tl�e nortli side of the residence will likely continue to setUe and creep downslope. Additional setUement and creep will likely result in increased ofiset of tlie retaining wai! and deck supports. In our opinion, several remediation options may be employed tc mitigate tlie sottlement and lateral movement of the slope fills. In our opinion, the existing fill located on the north and east sides oi tl�e residence siiould be stabilized. Based on tl�e results of our study, we recommend construction of a new retaining wall in place of the existinc� timber wall which is exliibiting signs of failure. As an alternative, thA loose fill czn be removed, provided measures to stabilize tlie slope are implemented. Measures to improve suriace and subsurface drainage should also be implemented. These altemati�•es are described in greater detail in tlie fcllowing sections of tl�is report. Ednh Consul[nnis, Inc.