1415 75TH ST SW BASE FILE 2016-01-01 MF Import

_� 0'Donnell, Drigham 6 Partners, N. W. E-1548 May 19, 1901 Page 6 No well defined groundwater level was observed during tl�is study. tlowever, light to heavy groundwater seepage was observed in the majority of. ttie Test pits from the ground surEace to a dep:h of about nine (9) feet below the exiating grade. This seepage generally m rresponds with ��e contact betwer.n lhe looser surficial soils and the dense till and ic r�m:noi;ly referred to as a"perched" groundwater condition. 7'his occurs as runoFf and precipitation, upon infiltrating tlie looser sur[icial soils, encounters a less permeable soil, such as the dense till, and becomes "perched" above tlic dense zone. This condition would reach a maximwn durinq periods of sustained precipitation, but may be expected to flucluate seasonally. Further, considerable amounts oE caving occurred witl;in tlie loose surticial fills encountered in Test Pits TP-10 and TP-2�• DISCUSSION AND RECOMMENDATIONS General Uased on our Cield exE:loration, laboratory testing and engi- neering analyses, it is our opinion that the proposed buildings may be satisfactorily supporled on conventional spread footings bearing on eitlier tlie dense �nderlying native till soils or, if required, on structural fill. Even thou h the test its-diri.-��r P1tond to proposed E�un�� t s our opinion, based on our knowledge of geologic and soil conditions, tliat tlie glacial till or otlier glacially consolidated soils will be encountered at Einished grades. All structural fill sho.ld Ue pla^ed and compacted in accordance with the Site Preparalion section of tliis report. The primary soil engineering features to be considered Eor development of this site are the plaeement and compaction of the deep fills, particularly along tlie edge of tlie swamp area on tlie western site, nnd tlie'removal or relocation of the existing fills and the retention pond in the northeast corner oE the site. We anticipate that.total settlements under the proposed fill and building loads will be on the order of one (1) inch where buildings or fills are pla�:ed on the dense native till / To provide a stable slope along the west edge of the deep fill in the swatnp area on the wesCern site it will be necessary to key �tl:e toe of tlie [ill into firm nal:ive soils. io accomp- lish this, substantial amounts of tlie existiny organically con- taminated peaty matcrials will requir.e removal. If they are not rennved then a potentially unstable condition will exist in tt� fiJl embankment. (fiie remova o the organic mater a s may Grih Consullanls, Inc.