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a \J page 2 Proposed Apartment Site� Roseville, Minnesota Ground water entered.both borings, and the levals and times of r�cording are given on th� lo�e. Thc ground water level c�.n be ex�ect�d. to vary �rit,h the s�asons of tha year and from one year to the next. We under�tand that typi�al 2�- story apartment buildinga with half buried basements ar�e planned fo�r thi$ si�.e, although no dafinite details cor�eerning the building� ar th�ir propo��d laca�ions on the sit� are available at �his time. W� assume tha i th� load under a minimum w�.c�th (2° ar less) wa,ll £ooting would not exceed 2QOa to 2�00 pounds'per �quar� footr and that th� total load would not exceed �000 tn 5000 poun�.s �er �3.nea1 foot. Tha granular scril found below dep�.hs of 3�' and 42 � in borings 1 and 2 r�spectiv��,y would be su�.table for spread footing ,foundatians using a ur�it .faoii.ng loading on �the order of 3000 pounds per squa,re foot. It should be noted that the presenae of trie unclerlying w�aker o�.ay loam could have a� adverse effect ori the allowabl� unit l��ad.. in� �iven above, d�p�nd�.ng upon final footing �lavation,a�rid tYie total footin� lmad. It may ba ��en from tt�e test resul,�� that the �lay laam has a good density. In the area of bering 2� evme consideration Qould be'giv�n to taking the footings dowm only throu�;h the or�anic gilty clay loam to the underlying clay found below a d�pt}i of 2�rr, whieh woul�l b� suitable ior only � very ligh� unit loading on th� order o.'P 1000 praunds per sque�re foot (basecl on the p�n�tration re�istanee). It may also be seen from tha test reaults that this soil has �, fairly low density �,nd a fair7�y high liquid limit, whioh would indiQate the po�sibi�.i�y o� considerablc settl�ement, Cbnsiderable differential settlemant could als� ocaurs partiaularly if the de.pth of the clay varied conaiderably ar if it was ab��nt under por�ions of the build�.ng. Fc,r the flo�ar slabs, we su�ges�c that at least the existing fill and�organie silty �lay loam be removed from th� entire buildin� area. A good acmpaated granular fill should then be placed to required fl.00r elev�tion whare necessary. Some consideration could also be given to excarrating the fi11, ihe organ�c silty �lay loam and the rather soft alay from the en�ire building area, refilling to re- quired floor elevati_on with a good. compact�sd granular fill and conatructing the footin�s on the fil.l ar natural granular s�i1 at normal elevation. Tho e:�cavation should extend bayand the edge of tha fadt�.�gs a distance at least equal to the depth of fill beneath the foatings. The sueces� of thia mathod depends upon re�moving a1Z of the undesirable soil and upon the pla�ing of a good compacted fill. 7l'his m�th- od would also provide suitabie �upport f�ar �he floor slab. � The high ground water 1�vel could caua�e some conatruGtion difficulty� depending upon final faoti.ng elevation. It appaa�-rs that the u,se of a w�ell point dewatering system would be necessary to dewater a�.�y excavation below water level in the gxane ular soil. If' thare are ariy� question� regardin� �his report, �r if we Qan be of any further service ta you� please do not hasita�e �o contaet us. We would gZadly review this report when definite buiJ.din� locati�ns and floor elevations are �ele�tcd. About 50� of the soil samples will k�e held a.t this offiae for a period of 2 months and w�,11 th�n be d�soarded unless w� are notified to hold them for a longer period _. . ... _. . , . . . . _ .,. _ ._ .