AgdaPkt 2009-08-03 spc, clsd and jnt

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7A Page 22 Cordilieras Cr�ek Updafe since the�eb. IO hearing .In March,BA�G excavated a trench along th�top o€the gossible landslide feaiure and submitted a report on its fin.dings.The excavation occurred without notifying the City in advan�e,so to our knowledge only BAGG personnel and�teir contractors vzewed the exposuxe revealed by the treuch.The trench was also excava#ed within the cr�ek setback zone without prior approval of the City Engineer,as is required by the City's creek protection ordinance.3n the applicant's submittal Iettex dated Aprii 20,2009,Mr.Rodi.ne states:"To elirninate any reasona.ble doubt,this Iatest report recanfrms tbe.findings set forth in BAGG's three previous site invesrigatiox�s. Simply stated,there is no scaxp,no laudslide,nor activ�erasion on the sub,�ect propert�hased tzgon the e�npiricaZ evidence prese��ec:t by BAGG engineers." This statement,unf.ortunatefy,i.s spin�n the BAGG repart.BAGG reported that they did not obs�rve soii slip or movement planes in the trench,but they do not discus�haw the geologic relativns in the trench preclude Iandslid.ing on the site.To refute our fair argument,BAG�'r wouid have to shvw that a landslide could not produce#he observed f.eatur�s.The location of the trench ad.jacent to the old foundafiion structure prachcally . guarantees that the treneh would encounter fill.Their 1og,�owever,shows�ha#fili is Iocalized adjacent to the old founda#ion,as would be expected Man-induced tlisturbance � at the creek tvp is cleazly appare�t and reiated to the foundation and ret�.ining wall canstruction;such activity would like�y serve to obliterate subtle evidence of sliding.In reality,the trench lug and unit descnpti�ns actu�ily argue against BAGG's theary that the anomalous slope feafixre,which i.ncludes an arcuate steep upper slope,flat mid slope,and oversteepened Iower slope that ea�roacbss i�nto the creek channel,Ys com�oscd af fill that was dumped into the creek to pmvide for a larger buildi.ng site. In respo�se to this report,GE�INSITE has conducted�et ano�her review and sit� visit;the resul�.s of their anatyses are attached.GEOINSITE concludes,"the tog of the trencl�presented in BAGG's report does not preclude�he presence o�Iandsliding. Rather,th�g�otogic relationships depicted on the log reinforce our opinion that Iandsiiding has occurred at this lacation,and is the most reasonabie explanation for the observed gQOlogfc and topographic conditian�." New plans submitted to the City show tha.t th�homes on lots 2,3,and 4 have been moved slightly to accommodate a 15'setba.ck from the tvp af the bank as defined by theu engineer;t�.is definition of fiop of bank was accepted by�he City's Community De�elopment director for the purpos�;s of starmwater filtration.The new pians atso provide far an alternative storm water plan that does not r�quire the construction of an outfa�t in the creek.Both vf these changes will 1ike�y reciuce the like}ihood that tbe .developmcnt will increase the erosion ha�ard of the bank.However,the top of bank ��'':�r�efined by the applicant lies well within the observed slid�mass,and i#is unclea.r,based on the evidence at hand,haw much of the bank may be s�zscepribie to catastrophic failure. CrEUINSITE has pmv�ded clear evidence that significant bank failure and erosivn have alread.y occuxred on the site and has stated that cu�rently prnposed n�uri�tions are not