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Home My WebLink AboutDEV 2016-0043; Vaughn Residence; Geotechnical Update; 2017-09-18GEOTECHNICAL UPDATE Proposed Single-Family Residence 2605 Crest Drive Carlsbad, Californ ia HETHERINGTON ENGINEERING, INC. I RECORD COPY I I ·--~ ~L fo/1A1 ~nHfat Date -------·----- ;, HEJ~ERiNGTOlN ISNGINIEIER~NG, INt. SOIL&'FOtJNGATION ENGINEERING o ENGINEERINGGEQLOGY o HYDROGEOLOGY -· • :· ' • • • ',O • 0 ' •• •• ' ' ''''a •· • ' •' ' ., ., ' •' • Stie and Ryan Vaughn cl o .J epnifet· Chai'les • Ai·.chitecture 817 Kalpaii Cirqle, Uilit lH Carlsbad, California 92008 :Attention: Sul:>jeet: Ms. Jem1ife1: Charles \ .. ",' .. .,. GI\QTECHNICAL llPDAtE Propos.ed SingJecFamily Residencc· 2605 Cr6st Drive Carlsbad? California References: · Att:a6\led Dem, Ms. Charles: September 18, 2017 ProjectNo. 8427.) . Lci~Nci. 1'9355 In accordanCle with yqur request, we. have pefforlned a geotechnical upd!lte for the pro11osed sihgle-falni!y 1:esidence at. the subject she, Om work for the, update was · performed in September 2017: J'he pu1pose of om work was to updat~ tl16 previous ge9technical work performed by B &, B Engineering, In.c. (Referenc~s 10 .and 11). We have been provided with a "Grading Pian .. .?' (Reference. 13) depicting the CUIT()l).t proposed development Tl:tls update in:ciudes .seismic design• criteria in acco1'dance with the 201 <j Califsnma Building Code, . Oiu· scope of.work for this llpdate-ihcluded the.following: • Resear9h l)lld review 'of the available plans and. reports pertinent to the site. (see References). • Site.recommissance. • Engineering and.geologic imalysis, • Preparation of this rep01t providing 0111··findihgs, conclusions and recolil!Ilegdations. 5365 A\/enlda Encinas, Suite A • Carlsbad, CA92008-4369 • (760). 931-1917 • Fax (760) 931-0545· 333 Third Street: Suite 2 • Laguna Beach, CA 92,651-:/306 • (949) 715°5440 • Fax. (760) 931'0545 www.hetheringtonengineeiihg.com ' . . . ' ' ' ' GEOTECHNtCAL UPDATE fi:oject'No. ~427'.1 · LogNo, 193.55 . Septem)Jer }8, 201'7 Pa.ge2 ' ,;. The "Lill1ited ~ite, $peqific $oil Investigation ... " (Reference JO) shpuld be reviewed for (\ie r~ults of . ficlcl ·arid laboratory .. work previm,sly perfo11ned and geotechnic~l reccinnn~,1daticn1s that are nottevi$ed or dtiplicaJ~d'.in thi_s repo1:t: ' 'th~ subje'<:t .propei'ty is located at2605 Creit Drive,. Carlsbad, California (see Location M!!p'. F:igure 1). TJ1e,sit~t9\l11Sists of a:.reJatively level, vacahtprciperty: The pr,operty Js boyn,d~chby re~idential properties to the north; west and south, andby:trest Dih,e fo'\fie east, 1Jf site i$ covered wi\h a s,earse growth of we.eds and ~i'asses. PREVI©BS GRA.DING 1s iljdicatef ln tfie "Results of. 901npac.tion Testmg and Inspection .. ;" .(Ref§rel)ce,JJ), th'e .site !;as lJeeil 'previously waded for a previously proposed ,residence (R.eferen'd() 12). the cunent plan djJfers f~olll the wior plan, consequently; .the Iimjts of' p11st report~d gr!!dirtg•are not adequate)o provide sup1fort for, the proposed .inil)toverrieti:ts·. The o_nsite s_oils fopbr_teclly ·po~sciss a very low expansion potential and ne'gligjjlle water-soluble. · sul:fates.(R.efererice l()). · · · PROPOSED DEVELOPMENT It is. otJr up.dei'standing that proposed deyeloprnent consists gene1-ally' of a c11stom, two- story, ,sing\e0:fa,mily resid~n<;e with attached garage, raised decks, ahd,conqi:ete flatwot)<. We aritipipate WOOdtfra111e constructioJ.1 founded on conv.ention!)l coniinµous/~p1·ead footings with a, raise<l-wood floor for the residence and sJabcon°grade floors for. the garage: Biiilding .Jo~ds · ate exl)ected to be typical of this typ<: pJ,' relll.tively light 'construction, · · · The "cu!;·ent "Gradipg Plan .. .'' (Reference 13) indi'c!!tei; that proposed gradJng cobsi~ts.of 9utand fill. MitxmlU111 design cut and fill depthsate.approximately 5-feet or less. No slope~· are:proposed'. · · SEISMICITY The site: is l9cateµ in· a mo,derately active sei.smfo n;gioQ. Ground 'shaking d11e to earthquakes ~ho,µld be anticipated dudng the life of the proposed. improv.em:ents. The following. fable .lists the known active faults that would have. the most significant impact on the' site:. · HETHERINGTON ENGINEERING, INC, LOCATION MAP HETHERINGTON ENG IN EERING, INC. ~ N I SCALE: 1" -2000' (1 Grid Equals: 0.5 x 0.5 miles) 2605 Crest Drive Carlsbad California GEOTECHNICAL CONSULTANTS PROJECT NO. 8427.1 I FIGURE NO. 1 GEOTECHNICALUPDATE Project No. 8427.i · I..og No. 193~5· Septe1i1ber 18, 2.017 ·Page 3 · . Fau,lt N ewport-lliglewood/Rose Cahyon . · · (Pel !Y.\ar'Section) <2..S-rriilesZ4~kilomefors sciuihwest) C;oi-onado Batik · · ) f18.6-mili,s/30.ldiomefer;"southwest) · .. . Elsihore.(JuliairSection) . (2.8-ni\!es/45Cki)oil1eters:n01't!foast) .. SEISMIC,EFFEC::TS 1. Ground Accelerations Maximum Pl'obable Jl:ai,thqti~ke .. SlipRat,e rM.onieht Ma•nitude1 rmm/vJari 1:0 \. 1.5 7:4 3.0. . 7.3 3.0 'fl?.e most signit),9ant prob~qle earthqualfo to effect 1:he .site would_ be a 7:omagnittide ,yartp.quake oir. the Newpoi:t Inglewoo_d/R9se Canyon fault: Bas~d O!l Section 1803.5.17 ofthe. 201.6 Califoi:nia Building Code, peak ground .. accelerations (PGAM) of 0:466g iµ·e p9ssib\e for the desigl). earthquake. 2. Landsliding Review of the _referen~ed geologi<; literature indicates thM the relatively lllvel property has. no pi·eviously mapped landslide deposits and none were foil_nd dµring prc;vious site subsurface expl_oration, The risk of seismically i11duced landsliding effecting the _site js ~onsidered low due to the dense undedying tetrfu:e deposits and relativel~r.flat topography. . . J. Ground Cracks TJ1e risk. of fault sw;facc, rnpture due to, acp.ve faulting is considered· low due to the abse11ce ofari active .fault on site. Grourid cracks due to shaking from ·seismic events in the r~gibn are possibl~, as With all of souther.11 Ciiliforcia. · · · ' · · · · 4. Liquefaction The 'risk' of seismically induced liquefaction within the site is considered fow due to the und~dying'dense terrace deposits and lack of shallow groundwater. · · HETHERINGTON ENGINEERING, INC. GEOTE<:lHt-ITCt\LUPDA'l'E PioJ~ctN<'>, ~427:I . . . . . J.:og~o. }93.S5 . Septem!J,er l8i2017. Pag¢4 s, Tsui1amis t TI}e· risJc of i i~un~i :av~rs~i/.tmpi?tihg' ,th{Mt~ ·is coµsic;I~reg Igw d~¢ to. the elevatj9po:fthe•s/te•llo,pv,e s,ea··1e~eJru;tddi§t#ncefi·ow the·coa~t1i . .ne: ,, ' eoNcLesr0'Ns:ANooocotviMENbA::tr0'Ns ·· t Gelieral . ~a~_ectonoliJ; ~iter~?Olll!ais~~*CiJ; the,$it~'is i,11a·.·sitjJHiJrion,dj#oJJ}s ~tlpQitecJ,,,in the "Re~\JJtl pf QoinpA?tibn '(estJng md J11specti9\1,·· }\ (~efor~n,ce J'J), 'I'lj:t: J?['OPQ?ed si11gle.sfanill:Y. r~sic;l".11cf i,s i;:6µsid~r~d· Je!lsi151~ from,. a. ' geptilclu\jcal .• sta11qpoint CJritilitjg,and, founc;latiqn pJ~[iS sijoul\i, fOn?)c;l~r theiappfol?#ate geoiec;JuilcaJ ~eaitJf,es . . of the ,site. TJ1e, proposed ,CQJllil!'llC,HOn fa 11,0(!l!lticiJ?afec;I tp ~c:jy~isei:Y i111pictthe adjacent pi'opilrties from .a geotec;lmip'al ~tl)il.dJJoint 'provided the rec9!11ffienf!ation.s. presented in ,this report and ,gqoci coµs{ri\ctioh iii-actices are iniplerile!lted q.tii:ing design 811d constrqction. . . ' · ' S.ome cjoC!llIJ,el}ted.eidsting c;o111pacted l;il[exists. on, the site .. Dui,:jng p):opbsed iufi!ie site gradin.g, the existing compacted fi!r will be tested to . deterp:rirw if ii i.s sµitab.!e in its C!JJTentpClp.djtipilfor ~Upportcifthepl'QP,OSed,iiJiprovements, 2,. Seis11:foiafardetets for StrncfurafDesign Seismic considerations thar may be used for structural design at the· site, based .on Section .l(il~ of the. 2016 C:hlifomiii Building Code and AS.CE 7,,10, ;inchiq6 the Jojlowio:g; · , · · ' a; Ground11oH?ri • Tli,e.:]?ropcisePr~sidence sli.ould,be qesig~eil aild cppstt;ucteci tp tt;si.~t the .effe~t.s 9f s¢i$mjc, gr<iup.d' rocit\ons' ~s prpvicleq in Se~tio1,1 1613 9f t]:ie 2016Califorllia.13li(ldihg·Code, ~itef\1di'ess; 260Q Crest I:)~\ve, Ci1rlsbfld,,C;~lifofnia ' Latittid~: 3.3.J729°N /' ~ET~ERINGTQI\! ~NQINEERING;. INC. ' GEQTECHNICAL UPDATE Project No .. 8427. l · LogNo. 1'9355 Siiptember 18, 20.17 Page 5. ,b. Spectral Response Accelerations • Using the. locatiori of the property and data obtained. frori1 the tr.S:G:S .. Earthquake Hazards Progran1, shortp~dod Spectral Response Acceleratio11s'S, (02· second period) ruici S1 (1,Q secqnd period) are: s, = 1.125g Si.,=0.432g c, Site Class -fa a_ccor~ance with Chapter ;w of AS.CE 7°10 and: the,.undeflying. ge,016gic condjtj611s, a Site Class J? is considered appi·qpri11te for the .subject pfopeity. -· d. Site Coefficie11ts.F0 and .Fv "Jn accordance with Table 1613.3.~ arid considering the values df S, and ,S1; Site Coefficients are: · , Fa= LOSO Fv= 1:568 e. Spectral Response Acceleration Parameters SMs and SM1 • In accqrdance with Section '1613.5.3 and 'co'1istdering the values of s; anfS1, ahd' Fa.and Fv, Specti'al Resporise Acceleration Farameters for Maximum Considered Eat'thquake are: SMs = l.18Jg SMr=0:678g f. Design Spectral Response Acceleratici1LParameters Sos andSm -In accordance with Sectio1116l3.~A and considerilig the valµes bf S111s and Sm1, J;:,esign,Spectral Response Accelera,tiqn:Parameters fot MaxilllUlll Co11sidered:Earthquake are: Sos"-0.78'7g So1=0.452g g. Long Period Transition Period -A Long Period Transitimi. ~e1fod of TL: = 8 seconds is proviileilcfor u~e in San Diego County. Ii. Seismic .Design Category -In aqcordance with Tables 1604.5, 1613.3.5., and ASCE 7-10, a Risk, Category fr and• a Seismic Design Category D are considered appropriate for th(l sµbject prope1ty. 3. Site Gritdfog Prior to grading, the <ll:ea of the proposed impi-ovements should be cleared of existing surface obstnwtions, vegetatio11 and debris, Materials generated during cl~arihg HETHIERING'll"ON ENGINEERING, INC .. -• ., -> -l . GEOTECHNICM, UPDATE' P;·ojectN~·. 8427:l · · ·· LoifNo.19355 September l lt,2017 Page.<i ' ' \ ' ' . ' " ' ' .. ' . should. b.e dispos~d 9f at iµ1 ilpprqved locati.Qp ,off0*e,. H~J,es re~ulti11g froni (11e: 1·e,111qvals of b(lried oqstrnc~ibris which'el(teiid below f1;i)ish:ed site grade, should.qe backfilleci with compac,ted fiii: qr\Ji:ail co~ciete. ' ' • ,. ' ' . ., ' Withill• the,Ji!llit~ pf)h~:pl'Clj)O~e/1 tesiden!S!); ,gai'ag¢,9n-gradi,dinpr,01:1eme11fs, !!1'1c! to 5,feet;bey()pd, 'where po~si,9Ie;. el(istfog .. lqose weafl{e,l'ed' teij'a<:eicJeJ?OSits an'.d ·exfstil}g .fill ·sh9t1W;Pe .. reni:oyeq d\i~vfrto gpp1:9v¢d teiracc;:deppefifs,.'D.l,iring,:,proppse,d .•fufute . · ··sitegq~iiiln~; tiw~l'i~iil1t go.ntpa~ieiit1I~:wiJ.f ~e. t&~te{t/1 :d~tef11jjne:ifiit ·i.s:,sJlJt~We for . ·Sllppo1i of tiJ:e proposed' unproveine'r)ts, if;Ys51;,fl1e.,existjrig:Jill·:cafr: ]'eajafo ii1 its. existii1g qqnciition: We iiJ'i~ciJ?.ate ;'.emov~l .c\¢ptns' oµcthe•or(,l~y .'.qf)Ife~t .bel6v,exi~tii1g, site. grades. · A'.ctµal l'llmo:vat deptlis sl19ulcl, 'PB' ·cieiei'l11/n'.ed hi tlie, field' by 'the Geotecb;riical ~citis~lt!111tpa~ed,imcon,ditipns ~xpq~ec(dii}ih~ftr~diµi:' . . . . Foll9wipg remoy'als, {heel(pps~dsii\Jgracl\\ .sOil; siio,ti\c;l · 1Jtsc;arifi¢c!ct.~ ·a clepthpf 6 .tp 8°iAches, moi~tureQqnditionec! tci,~b.oi,t optjii:)firi:r1;ipi~t1lre,ccin,fe~t ~d·~oippacted·to' at 1¢ast 90-percent l'ehitiye CO!IJpai:tion (ASTlvI: I)') 5,~7). , - Eill shoulcl b,e 111qi~·e. coqclitiol).ecl to apcYµt. dptjtpiliµ nj.ois~~ gcintent .and c9lllp,acted by·,mf6fianical w~a\lf in urtiforin:, horizontal lifts of 6. to, 8)11qhes ht ilii9kness. A1J. 'fill sh9,uld _be, 90111p·a~ted tp a m,iriirri.uin relative ,c6n'ip11ctiPP \if 90, pefcent qased 1ipo11 AST!V1: D 155J: The on-site h1aterials ani suitable: for use as qompacted fill proyicled. fill.vc,,g~tation anc!; 1i:.br~s ai:e !emoveq. R:9ci ~;agIJ?,ell,ts over 6-iµches in dimension and other .perishable or unsuitable materials shotild b'e ' excluded froin the fill. . . ' ' ' ' ' ' ' ' -.. All· gr!icling and c;oµ1pactio11 should pe qbseD1ed l'!nil test~ as hecess!ll'y by the Geotechni~a.l Con.sultant. · · ' . 4. Foundation and Slab,Recommendations The .. proppsed ,structure ~h~1!1'd' be. ;~uppprtec\ on , co_riveritjgniil co1\#nu61.jii/spre~cl (ootJiigs Joiµi,9eq · at \east J84i11.ches, info co!IJpactec! 1111 ·· aµd/or ,apprqyed; te;nipe deposits. Cori\inq/)us .footings sliollld be at ie!!eft liinchis wide, and reinforced wi.'t!i an;!inii,num of four f!4hars,. two t9pa!!d .i~o.Bottoip, Foundations l.ocated adNcimtfo utmty trenches should eX.t!;lJ\d below a l} l Jho11zonfal to ve~tical), pl~e )\'cijected upward from the bqttolfi of the trench. · · , -,-., ' -.. . ' .,· Foundations bearing as t'ecommended may be designed .for a deadplus live: load bearing value of 2900°pou11cls~per;;square0fo6t. This V~\t1e, may ptdl!creased by 01,ie- thfrfror loads including wind .. and s..iismic forces. A latetal~earjng'value of 300- l:IETHERINGTON ENGINEEI.CilNG, !N~ •. ,I • GE(YI'EGHNICAL UPDATE PtoJectNo. 8427:l ]'.,qg No. 19355 . Septl;lmber 1~, 2017 Page? ,pOU)ids~perasqual'e-foot per foot of depth and a COefficierit of friction qetween. foundaHo~ soi] and co11c1·ete of 0.25. may be assumed .. These values assm)le that focitmgs will' ~e P,OU!'t;d,)1~a\agait1st !lie fo1.1i~dati01i soil,s: f q~ti~~ 'eirn\l,Vlllior~ s~oµ!<;I be ob,stiryed ·by the peptt,chnical GonSlJ,ltf/,I1t prior to the p\acemerit of re:mfotciJig steenn ordei:to verify tliat they.are fow1ded in suitable lfoaring ni.aterials: .. . , . . tot~! ancl"differep.tiar sy'tti~n:ient due to fom1datiori load~ fa cbns,idered0~o. l,le. less than. 3/4 ~p.d 3/8°mcJ1,,ies'pective]y;'forfojjJ1da!ions fotinded as,1:ecOIJ1llltfodea, , • . -' . . ' . '. . ., ' ~1;:ib-on-gra<Je floors supported by compacted fill and/or ~pprovect te1,·~ce: dWosits , sliould. have a. 111ipim.um thJcknesR of s-h1ches and' sJfouid ber~inf()rceci with #4 bars spacf,4 at l.~-iqc;h~s, c~nte:r·to center, i11 two directions, and SlJppo~ted 011 cl:i~irs so th~t ihi:: rein'forcerrj!,nt)s iit,,m,islsheightiri.the slab, . Flopr slabs' ~i;ioµId be underlain: with ·a mdistute· Yapqr ,retarder cqnsistmg of a 111hlfo1ilin. lO"nnl •pQlyethylene me1I1brane. At least 2sinch.es of sand sho~ld be ,placed 'over tl:ie vapor retarqer to assist iJi concrete curfug and at least 2-inches of sand shoajd oe pl~ced lielo\.v the vapor teti!]:der. The ·vapor retarder shoulc! be placec! in agcorclan.c\l wi,th AST]y[: .E 1643. Prior to placing cdncrete, the slab subgrade soil~ should be. thorb~ghly moistened. \· . ~ Vapor retarc!ers ,are rt9t intended to provide a watemroofing function. -Shoitld .niois.{ure V~JlOl' S\)rtsitjve floor coverings be planned, a qualified Q,On5ultant/c9p.tr~Qtbr should lie consulted, to evaluate moisture vapor tr1111srriission rates ahd to provi9,e ,reconunehdations to · mitigate · potential adverse m1pac_ts of moisture · vapor trailsmissiorts on tlie,proposed flooring . . ' 5. eonci'efo Flatwork: Concrete flatwotk should,be at le11stS-inches thiclc(actuaj) arid reinfoi'ced with No. 4 barf spaced at·l8~ilich~s on°center (two diJ:ections} and placed on cha,iJ:s so .that tlie reinforceinent is· in· the center, ofthe concrete. Contraction joirtts should be providec! at 10-(eet spacing (maxinmm} Joints should creatti SCfllafo panejs wh~i·\l possible. For rectangular panels (where necessary) the long dimension: sho4!4 be ho more than 1.5 times the shint~ension. J.oint depth shoµld be at leait 0,25 times_,the flatwork thickness, Expansion jofuts .should be thoroughly sealed to. prevep.t.the infi!'ti·ation:of water into the uridt":rlying soils. HE:fHER.11\!GTDN ENGINEERING, . INC, GE0TECHNICAL UPDATE Project No. 8427.1 ·· · · · Log}~Q. 193$5 Septembei·J~,.2017 "Page 8, . 6. Sulfate Conteilf ' 'A-.. repre~~j1t~#ve :sanip\~·'o.f ithi:l(oµC~ite, S~ils' ~ils, preyi~tisly SUbgii(\~\I: J\r. ~(1)J'fite t~stmg .. 111¢ Jesuit of tne sulfotfcoIJ°tenftesVis,\¢po1iedly '()'.Q03o/ci (Ref¢1'l;nqe · 1q~. 'Fh,e/SU[{afe,Qoi1t,e11t··js,qQJ].$i~\ep.t,with .. ~·.;neglif!;jble:.st\lf!it~· e,){pQS,~\)\Cla~.~ifida!jonp¢1' 1'!,ibleA.2.1 . 0~ ![1.e A:ni~ri~!l11 Coiicrete Iri~hute J>ublfoat\01T. }18; . c9n.secjye11Uy, im speci'al prQvis~ons for(SuJfat~!'esist!\llt· 9q11crete: are consid<;red:)1ece~iart .. Qtlier corro.sivity te~tiiig has n<Jtfi~el'1° p~1t~i·rned:; cqn.;egqentJy,·th~ op.0sifr·· sciiis, ·W?tU~lie ass.urned tb be. ~9yerefr conosive ~9. b1.ni~4>1Iletal~ ti11les$ 'testi1\g '.is p~rforrned to indicat\') otb.erwise.. '· . . . ' 7 .. · Utility Ti·enc!J..Ba:cikfill ;:\ Utility tI'euch tii9Ihill sh<:lµld be compacted• to at· least · 90, p¢rce/J.t . J,'e)a,tive compitction (AS'J7l\lI: P 1?5;t). Biic,1&11 sholild be tested !111d: 6bservec.J · liy 11\e Seot~.chnical'·C<Jnsultaht. 8. Site Drainage The following l'ecomrne11dati<Jns are •iittended to 1ninimize the pot~riti(ll ad.verse . effects of water on the sti:ilctin:e,a11d.appiu'!en_anc~s, •. a. Conside1'ittion, shoµld, ·~e .giy~I} .to 'providiµg roofi.g11,tters ap,d cl,o'wl,1spquts' that · discharge to an !\!'ea drain,systero and/or: to· sbit.able lo'c;ations away from the strncfute, , .b.. !,I.IL ~t.e drainage shoJJld birdfr~cted ·awa'y .frp1ll the st11,ict1,1re \\llcl nqt.1?~· ;illpwe,d to flow 9ver slopes. . ' c: ,No landscaping sho11Jd.be,allowe4,,gai.n~tthe sut16tin;e, rvioisture accumulation o~ wateriJrg :adja~ent to . fotind1ttioiis cijn· .reslil,t -in deterioratidn of. building mateI\alf!t11d Wll:Y effectJ6undatj9n pe1TOI1I)aI1i;e~ . . . . d; Inigated.,areas should not be over-watered. 0 lrrigation.'sho~fd be !intltedto that required to maintain the "v.egetati,im: ,Adtliti~hally, ~utbmatic syste)IlS 1lll)St be seasonally adjusted to mininiize overC:saturation J:iotential. pruticuiarly in the winter (rajiw)season; · ' . ' e. AU yarcl. an.d rqof drains shou,ld )le periodically c~ecked to verify they are 11ot blocked and flow property. This may be ac~orhplished either visually or,.in the HETHERINc;toru El\!1:;INEERiNc;, l!\IC:::; j Ii. .• QE0TE<Jf!NI¢MUPDA'I'E Project No. 8427.1 Log No.19.355 September 18, 2017 Page9 case of subsurface drains, by placing a hose at the inlet .and checldng th,e outletfpr fio.w. 9:. Rec_ommended Obse!'viition'and Testing Durin!; Gonstrnctign Tlw follo';Ving ·· 'te.sts and/or observations ~Y tlw Geotechnjcal Consultant are recoinrii.endl\d: ,, a, Obsetvatipn ru)d testing of grading. b. 'Foundation,excavations prior to placement offom'Is anclteinforcell]ent, c.,. CutjlltyJrench backfill. . . ·, ' d. ..Flaiwork subgfode. io, Gfading and Foundation Plan Review Gra,ding ancl foundation plai).s should be. reviewed by the Geotechnical Consultant to corrlirm conf911nance with the recommendations: pi·esented hen;iiIJ or to in,odify the . recommendations as necessary'.; LIMITATIONS The flllalyses, cpncll!?io11s ancl reco~enqati6ns contained. in this report are based on site conditions as.reported<in the. i'eferenced documents 811d further-assume ilie excavations to be rernesentati\f!l ofthe,sui,sllrfaCe COn'<l!tions thrifogho\Jt the. site. If different Sllbsu1faC~ cojlditions fron;i. those reported are obseivecl or appear to be present in previous excaya\io,ns d,ui"µig grading, th\l Geotechnical C.o.nsultantshould be.pj:Omptly 11otified for review and i:ec9nsidera,tion 'ofrecoinmendations. · Qur investigation. was,pe1formed using the degree pf ca.re and skill 01·djriariJy exercised, under similar c.irc:umstances, by reputable Geotechnical C:::onsul~811t~,practiciiig iii' this 01: iiimilru' localities. No othei warranty, express orimp!ied; is macleas fo the conclusiOns and prQfessional advice i.n'cludecl in this rej:Jmt, I · HETHERINGTON ENGINEERING, INC .. GEOTECHNICAL UPDATE Project No. 8427.1 Log No. 19355 September 18, 2017 Page 10 This opportunity to be of service is sincerely appreciated. If you have any questions, please caJl this office. au) . ogseth Professional Geologist 3772 Attachments: Location Map Figure 1 Distribution: 4-Adclressee 1-via e-mail (jennifer@jcharlesarch.com) I-via e-mail (marin.vaughn@gmail.com) I-via e-mail (rkvaughn@gmail.com) HETHERINGTON ENGIN EERING, INC. REFERENCES Published L ASCfi, "\Yfininmm Disign L.oads for Buildings and Other Struct11res", ASC):1·7-19, dated May.2010. ,. -. . -' -' . . . --I " .. '. 2. Cali(ornia. Errierg¢nc:y . Management Agency, "Tqum;uni: u)ltndation : Map. for Eh).ergency l3laiipfug; Qceanside Quadrangle/San Lui.s Rey Ql)adrangle/ datefl Juqe l,2009, . . 3. ICil'b, C~lifo1'ilia.Buildih~ <;:!ode, 2016 Edition, 4, IE)BO, "!y[aps 6fKhoWq A9ti've Fault,Near-$ource Zones ii1 California and Adjacent l'mtions of Nevada," Cfillfornia Division oflqines and Geo'iogy, 1998. . , . 5. Pet~rson, Marl~ P., et aJ, ''D()cumentaticm fol' tl).e 20l/8 Update ofHw I:(1utrd :Siates flationaf $\!ismi~ Hazards Maps," USGS Ope11;File Reporq008-1 i 28; di)ted2008. 6. Tllh, Sjailg S . .and Kennedy, Michael P., "Geologic ly[ap~ oftheNoftliwesten1.Pmt of SanDiego County, Ca!ifo.rnia," California Division. of Mines.and Geology, Open-File. Report 96-02; dated 1996: . 7. United States Geol9gic;al Survey, Emthquake Hazm·ds Pro grain, Seismip Hazards Map website: 8. Weber, F,H. Sr,; '':R.ecentBlope Failures, Allcierit Landslid.¢s, aµtl Rel!lted Geology of the N6rth-Ce1itral C.oiist.al Area; Sm1 Diego County, California," California. Division of Mines and Geology, Open-File Report 89-12LA, dated 1982, ' 9. 20Q7 W9rldng Group a11d California Earthqtialce P1·obability, "The Unifonn, California Ea1thqual(e Rupture)otecast, Version 2 (UCERF-2)," USG$ 9pen fil.e Repci1~ 2007- 1437 mid Califo~a: Geological Survey Special Report 203., dated 200~; ~ite Sp~ific 10. ''Limited Site .. Specific Soil Investigatipn for the Proposed Residential. €onsti'uction Lqc:;iti01} on Creit Drive, Carisbap, CA\ by B &. B Ehgineeriqg,Jp,i::., da~ed February ;24,2015.. . . l.L "Results of <;:ompaction Testing .and Inspectihn for the Residence, Lo911ted at 2605 Crest Drive, Carlsbad, CA", by B & B Engineering, Inc., dated OctbberJS, 2015. 12. "Grading Plan for Kapl1:1n Residence, 2605 Crest Drive, Cm:\sbad", by B & B Engineering, Inc,, dated "As-Built", November 19, 2015. HETHEFHNGTON ENGINEERING, IN~,. ProjcclNo. 8421:1 Log No, :19355 REFERENCES 13. "Qrading Plan for y~ughn _ ~esidei1ce, 2605 Cf¢st bdve\ by Coffey Eiigiiieering, Inc., revised elate February 1.'.i; 2017: . . ' 14. "Transfer J>f Geote.chnical Responsibility, 2605 CfestPri:ve, Cad~bad, Cajif9mia", ]?y Hetherington·Engi,rieering, Inc, dated September 8, 2017. projept-:t'{o. s427, ! Log.J'!o. 1~355 .HE!HERil\ll!llTON lei\lGINEE!i:IING, UH\!IC.