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I/4r. F.odney Schurmat~ City of Sail Le~mdro ?2 Septcn~bcr 2003 Page 5 T'erai7e~ability iesis were performed on i-cmoided samples from bull: sample ~-J , Remolded soil samples were compacted to 85 and 90 percent relative co~~~~paction` at 0; 2, 4. and 6 1~ercetlt above optimum moisture content, "hhe resltlts of the permeability tests on the remolded samples are presented in Table 5. Pem~eabilitic, on the order of l0-r and 10'' centimeters per second (cm/sec j were zn°asured, with lower p~rmcabilitics measured ire the samples compacted to 90 hcrccnt relative compaction. n~SCLISSTi(~hr AND RIL'CC~MN7EVDAT1~~l`:S The results of ow- ~eoteclv~~ical laboratory tests ir~dicatc the insitu moisture content of the dredge material ranges from 2G.6 tv X03 percent witi~ lhe. Iower moisture contents occutzing its the upper six inches of the dredge deposits. Laboratr~ry compaction curves developed foi sanaPles S-] t.iirough S-3 indicate optiniun~ m~~isttu•c contents to be betweGtl2?.S and 24 pcrectlt. These results indicate the dredge material is pear to si~t~if~cal~tly wet of optiniununoisture content. Tn addition, pern7eabilit~~ tests on remolded dt-edgc material indicate penrteabdity d~crcascs with an increase in relative cou~paction and an increase In n~loisnire content above optimum moisture. We anticipate a permeability on the order or 10~~cm/sec will require dredge material be moisture- conditioned to 2 to b percent above optimum moisture contierlt and co~r~pacted to at least 90 percent relative compaction. Because the insitu moist~~rc content ranges from 26.6 to 50.3 percei.~t, and the target moisture content is approximately 25.5 to 2~.5 percent, the moisture. content of the ~nsittt dredge material wili reed to be reduced prior to coir,paction. ~~Jc st~Geest dredge material be disced and aerated to acl~icve tuliforrn reduction in toisture content 7f dredge. rnateria~ is to be used as select :fill 1~or constttirct;on cif ti landfill cap, the dredge n~ateria] should consist of p~.-imarily clay and relatively free of sands and travel. We did not encou»ter siont~icatZt sand deposits during our field investiQat~on; ho~~~cvcr, we anticipate That pockets of sang »~ay be present at Ioeali«tl areas within the ponds. .~~ ~eotcchnical engineer or his representative should obser~~e the excawatior~ of dredge. material and flag locations of lri~h sand content. excavated dredtre material si~o~lld be disced and dried back to rviltiin the target nloistur~ C;OniCnt ranee prior to placement arrd compaction as IandF'iL cap material. The Clredge material should ve placed in lifts not excecdin~ eight inches iu loose tlziclcness, i»olsture-condilioned to 2 to 6 perce~~~t above c~ptimun~ moisture content, and con~hactcd to at least 9U percent relative compaction. ~Relstive compaction refers to il~c il~-l,~le,ce dry density of sell expressed as a percentage of the l~~~axlmtm~ dr}' di~~~sity o`t11e sri~nr material as dc~crm=ued by the AS'l~h~~t D] 55 i-00 ]aboratory c~mpachon procedure