2222 EVERETT AVE 2016-01-01 MF Import

• Subsurface Eip(orntiorr. Geologic Ha:nrd, aiul Evcrerr Sdmol Disrricr h/ninrenmrce Facility Preliminnrv Geoteduiirnl Engineering Report Ei�erett. lVashinqrai Design Recommendafions � 7'he on-site soils contain a moderate to high amount of tine-grained material (silt and day), which makes them moisturc-sensitive and su6ject to dismrbance when wet. The contractor mus: use care during site preparation and excavation operations so that the underlying soils are not softened. If disturbance occurs, the softened soils shuuld be removed and the area brought to eradc with structural fill. 9.0 STRUCTURr�L FILL No major grade changes are anticipated at the site and, as such, die use of strucmral fill will be limited to basement, utility, and overexcavation backtill. If strucmral fill is needed, then all referencu to strucmral fill in this report referring tu suberade preparation, fill rype, placement, and compaction of materials is discusseel in this section. If a percentage of compaction is specified under another section of this rrp��rt, ihe value given in that section shaul� br uscd w►icrc indicatcd. :\fter stripping and required overexcavation has bcen prr�urnx� to dic satisfaction of tt�e gcorechnical engineer/engineering geologist, the cxposc� �=ruund should be recompacted to 90 percent of the modified Proctor maximum density usin`� :1S"f;�i:D 1557 as the standard and to a tirm nun-yiclding condition. If the subgrade contain� too much moisture, adequate � recc�mpaction may be difticult or impossible to obtain an� �houl� probably not be attempteJ. In lieu of rccomraction, die area to receive fill should bc hLinketed with washed rock or quarry sp:ills to act as a capillary break between the nc�v til! an� the wet subgrade. Where the ezposrJ ground remains soR and further over exc,�vation is impraccical, placement of an enginecring stabilization fabric may be necessary to prevcn� �un�amination of the frec-draining laycr hy silt migration from belo�v. :\fter recumpaction of die exposed grounJ is tested un� ap��ru•:ed, or a free-draining rock course is laid, structural fill may be placed to attain desired gra�es. Structural fill is defined as non-orzanic soil, acceptable to the geotcchnical engineer, placed in maximum 4-inch loose lifts ��-hen non-vibratory compaction methods are used and S inch lil'ts when vibratory compacting, ��ith each lift being compacted to 95 percent of the modilic� Proctor maximum density using AS'C�L•U 1�57 as die standard. Compaction should be limited io static rolling by heavy drum type compactors when within 100 feet of the adjacent vihntion sensitive builJing wheie no vibratory cumpaction may be used. Vibratory compaction may be used 100 feet or further from the vibration sensitive building if monirored carefully. "I'hc rop of the compacted fill should estend hori-r.ontally outward a minimum distance of 3 I'cet beyond the location of the perimeter footings or roadway cdge before sloping down at an angle of 2H:1 V or shallower. 1'he contractor should note tLat any proposed fill soils should be evaluated by AGS[ prior to th�ir use in tills. This would require that we have ;i sample of the material 48 hours in adv:mce to perform a Proctor test and determine its licld cumpaction standard. Soils in which �b1ay 1, Z00! ;ISSOCGITED E.IRTII SC(ENCES, LVC. ��c�m,-xEao,eu r� �,,,,�e,�il.oi- �s.n Page 9 I(