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Home My WebLink AboutSubsoil Study,RECEIVED h¡o\/ T 0 20?t GARFIELÞ OOUNTY COMM U iJ ITY D EVELOPñ/iË ÑT Huddleston-Berry Engineering & Testing, LLC 2789 Riverside Parkway Crrand Junction, Colorado 81501 Phone: 970-255-8005 Info@huddlestonberry. com October 15,2021 Project#02332-0002 Stricklan Homes, LLC PO Box 1749 Rifle, Colorado 81650 Attention: Ms. Kortnie Stricklan Subject:Geotechnical Investigation 62 Meadow Creek Court Parachute, Colorado Dear Ms. Stricklan, This letter presents the results of a geotechnical investigation conducted by Huddleston-Berry Engineering & Testing, LLC (HBET) for 62 Meadow Creek Court in Parachute, Colorado. The site location is shown on Figure 1 - Site Location Map. The proposed construction is anticipated to consist of a single-family residence. The scope of our investigation included evaluating the subsurface conditions at the site to aid in developing foundation recommendations for the proposed construction. Site Conditions At the time of the investigation, the site was open with slight to moderate slopes down to the north. Vegetation consisted primarily of weeds and brush. The site was bordered to the north by Meadow Creek Court, to the south by a golf course, to the west by an existing residence, and to the east by a vacant lot. Subsurface f nvestisation The subsurface investigation included two test pits at the site as shown on Figure 2 - Site Plan. The test pits were excavated to a depth of 10.0 feet below the existing ground surface. Typed test pit logs are included in Appendix A. As indicated on the logs, the subsurface conditions at the site were consistent. The test pits encountered 1.0 foot of topsoil above brown, dry to moist, stiff to very stiff silt soils to the bottoms of the excavations. Groundwater was not encountered in the subsurface at the time of the investigation. Laboratorv Testine Laboratory testing was conducted on samples of the native soils collected from the test pits. The testing included grain-size analysis, Atterberg limits determination, natural moisture content determination, and maximum dry density and optimum moisture content (Proctor) determination. The laboratory testing results are included in Appendix B. 62 Meadow Creek #02332-0002 t0/tst2t Hud¡lltxton Bery Ëqìrdhs e Tcrint. LLC The laboratory testing results indicate that the native silt soils are slightþ plastic. In general, based on our experience with similar soils in the vicinity of the subject siteo the native silt soils are anticipated to be slightly collapsible. Foundation Recommendatio+s Based upon the results of the subsurface investigation and nature of the proposed construction, shallow foundations are generally recommended. Spread footings and monolithic (turndown) structural slab foundations are both appropriate alternatives. However, as discussed previously, the native soils are moisture sensitive. Therefore, in order to provide a uniform bearing stratum and reduce the risk of excessive differential movements, it is recommended that the foundations be constructed above a minimum of 24-inches of structural fill. The native silt soils, exclusive of topsoil, are suitable for reuse as structural frll. Imported structural fill should consist of a granular, non-expansive, non-free draínins, material approved by HBET. For spread footing foundations, the footing areas may be trenched. However, for monolithic slab foundations, the structural fill should extend across the entire building pad area to a depth of 24- inches below the turndown edges. Structural fi1l should extend laterally beyond the edges of the foundations a distance equal to the thickness of structural fill for both foundation types. Prior to placement of structural fill, it is recommended that the bottom of the foundation excavation be scarified to a depth of 6 to 8 inches, moisture conditioned, and compacted to a minimum of 95% of the standard Proctor maximum dry density, within +2Yo of the optimum moisture content as determined in accordance with ASTM D698. Structural fill should be moisture conditioned, placed in maximum 8-inch loose lifts, and compacted to a minimum of 95Yo of the standard Proctor maximum dry density for fine grained soils and 90% of the modified Proctor maximum dry density for coarse grained soils, within t2o/o of the optimum moisture content as determined in accordance with ASTM D698 and D1557, respectively. Structural fiIl should be extended to within O.l-feet of the bottom of the foundation. No more than 0.l-feet of gravel should be placed below the footings or turndown edge as a leveling course. In order for HBET to ßsue a subsrøde, øpproval letter for Gørlield Countv. øn ooen-hole inspectíon wíll be reøuired: ìncludíne proofrollíns and comoøctìon testínE. deoendíne uoon the suberade materiøL. In, ødÚìtion, ít will be necessøm for HBET to test comoactìon of the structurøl lill at everv l2-inch v?ltícøl interval. For structural fill consisting of the native soils or imported granular materials, and foundation building pad preparation as recommended, a maximum allowable bearing capacity of 1,500 psf may be used. In addition, a modulus of subgrade reaction of 150 pci may be used for structural fill consisting of the native soils and a modulus of 200 pci may be used for suitable imported structural fill. Foundations subject to frost should be at least 36-inches below the finished grade. Water soluble sulfates are common to the soils in Western Colorado. Therefore, at a minimum, Type I-II sulfate resistant cement is recommended for construction at this site. 2Z;\20fi8 ^I I.I¡ROIÊCT,5\02112 - Str irtl l¡n HoÌrrìs\02 ì ì2-llll02 ti? Mc¡dow Crmk Ct\?fxl - C*o\0211?-lXl0? LR i0l5? I ¡lo¡ 62 Meadow Creek #02332-0002 t0n5t2t úr8:n&ring& Tëring, Any stemwalls or retaining walls should be designed to resist lateral earth pressures. For backfill consisting of the native soils or imported granular, non-free draining, non-expansive material, we recommend that the walls be designed for an equivalent active fluid unit weight of 45 pcf in areas where no surcharge loads are present. An at-rest equivalent fluid unit weight of 65 pcf is recommended for braced walls. Lateral earth pressures should be increased as necessary to reflect any surcharge loading behind the walls. Non-Structural F loot S,lab a,nd Exterior f,'latwork Recommendations In order to limit the potential for excessive differential movements of slabs-on-grade it is recommended that non-structural floating floor slabs be constructed above a minimum of 18- inches of structural fill with subgrade preparation and fill placement in accordance with the Foundation Recommendations section of this report. It is recommended that exterior flatwork be constructed above a minimum of l2-inches of structural fill. Drainaee Recommendations Gradins ønd drøinase øre crít¡cal to the lons-term oerformance of the strugture. Grading around the structure should be designed to carry precipitation and runoff away from the structure. It is recommended that the finished ground surface drop at least twelve inches within the first ten feet away from the structure. It is also recommended that landscaping within five feet of the structure include primarily desert plants with low water requirements. In addition, it is recommended that automatic irrigation, including drip lines, within ten feet of foundations be minimized. HBET recommends that stnface downspout extensions be used which discharge a minimum of 15 feet from the structure or beyond the backfill zone, whichever is greater. However, if subsurface downspout drains are utilized, they should be carefully constructed of solid-wall PVC and should daylight a minimum of 15 feet from the structure. In addition, an impermeable membrane is recommended below subsurface downspout drains. Dry wells should not be used. As discussed previously, shallow groundwater was not encountered at the time of the investigation. However, a perimeter foundation drain is recommended. In general, the perimeter foundation drain should consist of prefabricated drain materials or a perfiorated pipe and gravel system with the flowline of the drain at the bottom of the foundation (at the highest point). The prefabricated drain materials or gravel should extend along basement walls to within 36-inches of the finished grade. The perimeter drain should slope at a minimum of 1.0% to daylight or to a sump with pump. The drain should also include an impermeable membrane at the base to limit the potential for moisture to infiltrate vertically down below the foundations. General Notes The recommendations included above are based upon the results of the subsurface investigation and on our local experience. These conclusions and recommendations are valid only for the propo sed construction. òJZ:U008 ALL PROÍICTS\o2332 " Stri0klän llonca\02332'0002 ó2 Mcrdow Cruck CM00 - Oro\02332-0002 LRl0152l.doc 62 Meadow Creek #02332-0002 t0/t5/21 @ Iluddleston Berry E¡tùr*lìg & T.slúg' LI-c As discussed previously, the subsurface conditions encountered in the test pits were consistent. However, the precise nature and extent of any subsurface variability may not become evident until construction. As a result, it is recofirmended that HBET provide construction materials testing and engineering oversight during the entire construction process. In addition, the homeowner and any contractors working on the project should be made aware of the risks associated with moisture sensitive soils. It is ímoort(nt to notp that the recommendatìons herein øre intende( to reduce the risk of structurøl movement ønd/or dømøgq to varvins deprees, øssocíated w¡th volume chønge of the natíve soils. Howeven HBET cønnot predict lpne-tqlm chanws ín subsurføce moìsture condítíons ønd/or the oreclse møsnítude or extent of volume chønse ín the natíve soils. ll/here sÍgnífîcant ìncreases in subsurface moßture occur due to ooor grødíng, ímorpoer stormwøter mnnosgment. utìlitv líne failure. excess irrísation, or other cause. eíther duríns co,nstruction ol the resuV of actìons of the prooertv owner, sçveral ìnches of movement arq possìble. þ adÚitíon. gryt.føilure to comolv wíth the recommendatíons in thß report releases Huddleston- Berrv Ensíneerîns & Testine. LLC of anv lìabílítu.n'íth reeørd to the structure performance. 'We are pleased to be of service to your project. Please contact us if you have any questions or comments regarding the contents of this report. Respectfu lly Submitted: Huddleston-Berry Engineering and Testing, LLC Michael A. Berry, P.E. Vice President of Engineering 42:\2008 ALLPROJËCTS\02332 - Stricklm Homes\02332{002 ó2 M@dow Cræk CtU00 - Geo\02332{oû2 LRlol52l.doc FIGURES z( I ,\ '| \.j. APPENDIX A Typed Test Pit Logs GEOTECH BH COLUMNSUS LAB.GDT 1CY15/21:0aemo-{z3Emuol\,o)o)l\)oooN)ot-mz{(t()ãotIo3(DØ\O ^ lQ iÌ{\¡ff\¡äoô¡ cÊi<-r-5 ÞFiXPæF? c- 2'!1ıo:J rD Oeg; ?iíã'trFôFCvf!1ræ^.<0ÞüE F'oÞö!.ocFrlgqf.|-o!noLmÕ{ooIoz!qtıC)o¿)o!1Pm(){zÞ=mo,N)=oqto.o€oãxooÊ={mv,{!+zc=trmn-{På.It6)mo'11zo{m(t,t-oootnc,E(Dmx()oz3mEoo-.{ıC)-(DtC)xImxC){ozooz{¡c){o7o0'c,Þmtt,vmo(ol\)ñC)4ml)xmc,E@oo3!|-m{mI(oNñttmÐmxo-{ızamzE,oïmxoD-{ızèeoo7Voo>2=-looismñtEotrÈxEeËtrttþtOIzlIâtel{mCD{!{LNmPoDEPTH(fr)GRAPHICLOG+mÐtrom(toÃtJozSAMPLE TYPENUMBERRECOVERY %(ROD)BLOWCOUNTS(N VALUE)POCKET PEN.(tsDDRY UNITWT(pcr)MOISTURECoNTENT (%)J-J=B-¡ tDøimn6)FINES CONTENT(Y.\LIQUIDLIMITPLASTICLIMIÏPLASTICITYINDEX.L'. t:.. -!rt.f'.i;-'.'.l.iLIÉ.foðo¡ı'Ø+oÌ,ØIt-*F-0)(tagt@9..(Dô-6)(!at-{=t-voıäqo39.ao;o(D€.Aã(s-g(¡,N\¡NN(¡(oo@oo3ooøE.o,9o(¡ô BH COLUMNS 023324002 62 MEADOW CREEK CT.GPJ GINT US LAB.GDT!vomo{zc=Emuot\)(¡)(¡)l\)ooo'\)c)rmz{CN=.c)ãoTo3o@\o^l!|ar-¡ry{äÕÞ ooã.r-5 Þ='{X3¡F!¡ ã :'!1do= ô oqc a ?ıF ÈryôFCv rs. u,æ<oaÈ.¡i Ë'3-ã3.üqR"Èìo'?sqr--l)!vgm()oo-{ız!n,q,Ico;,o!7emozÞ=m(t)N)(D0,o.oÉoıo-oocã{rfla{!{zc=_@#mRV--{qP.À)zomv,-ooomcl{D@mxC){oz=mdToE'-{ôc,FTD0to-ImxC){ozooz{vÕ-{o7ait'fg{mU,-{7tmtrt(oN)No¡mc)xmoTD@oo3!rnrmct(oÀ)?\).tt-{m7mxoÞÞ{ızII{mzE,o.rlmxoızo.?ono>E-roËFm{^míÐËËlhızo.2o1ozImrm=o2mU,{!{(t,ñmIoDEPTH(fr)GRAPHICLOG3+mnt-omCNon1t-{ızSAMPLE TYPENUMBERRECOVERY %(ROD)BLOWCOUNTS(N VALUE)POCKET PEN.(tsÐDRY UNITWT(pc0MOISTURECoNTENT (%)¿- -'l=äuimxoFINES CONTENT(Y,)LIQUIDLIMITPLASTICLIMITPLASTICITYINDEX"..r-. rs..i.,,'. .r.i. ¡"- .'.r..;. t¿¿ t\ . .tzjLTÉ.o(oll¡=ô6-{ol,Øo.t-otooqt@Ø¡t'o_c)fDar-+t-vgc'é=;-?o3o.Øf+ano(De6sË-.EàN(¡Nc¡,N(o(fIDoo3c}rìØıotIo(îô APPENDIX B Laboratory Testing Results Huddleston-Berry Engineering & Testing LLC 2789 Rive¡side Parkway Grand Junction, CO 81501 970-255-8005 GRAIN SIZE DISTRIBUTION CLIENT Slricklan Homes PROJÊCT NAME 62 Meador Creek Court PROJECT NUMBER 02332-OOO2 PRO.|ÊCT LOCAT¡ON Parachute. CO U.S. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER 20 40 50 60 100 t-Tg g t¡ É. IJJz lL Fz 1Ilo É. u.tÈ 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 100 10 1 GRAIN SIZE IN MILLIMETERS 0.1 0.0'l 0.001 I I 'tT { COBBLES GRAVEL SAND SILT OR CLAY coârse fine coarse medium fine Specimen ldentification Classification LL PL PI Cc Cu o TP-l GBI 9t21 SILT(ML)27 22 5 a TP-2, GBI gt2t srLr(ML)25 23 2 Specimen ldentification D100 D60 D30 D10 %Gravel %Sand %siÍt %Clay o TP-{, GBf 9t21 9.5 0.0 9.6 90.4 ñ TP-2, GBt gt21 9.5 0.0 r0.0 90.0 Huddleston-Berry Engineering & Testing, LLC ATTERBERG LIMITS' RESULTS Riverside Parkway Junction, CO 81501 970-255-8005 CLIENT Stricklan Homes PROJECT ìIAME 62 Meado¡v Creek Court PROJECT NUMBER 02332.0002 PROJECT LOCATION Parachute, CO P L A s T I c I T Y I N D E X 2 1 CL-ML @ @ 0 E 0 2A 40 1 LIQUID LIMIT Specimen ldentification LL PL PI #200 Classification a TP-1, GBl 9t2112021 27 22 5 90 srLT(ML) a TP-2, GBl 9t21t2021 25 23 2 90 s¡LT(ML) Ioô t¡J N@ NôçNo No ØF E Jo uo É.u F 3oo Uã N@ NôôIN Nô zo ts ô-Eo(.) Huddleston-Berry Engineering & Testing LLC 2789 Riverside Parkway Grand Junction, CO 81501 970-255-8005 MOISTURE.DENSITY RETATIONSHI P PROJECT NAME 62 MeadowCreek Court PRO.JECT LOCATION Parachute, COPROJECT NUMBER 02332.0002 CLIENT Stricklan Homes r0l \ \ \ \ \ \ 'I \ \ \ \ \ \ \ \ \ \ \ \ /\\/\ ./\\/\ Sample Date: Sample No.: Source of Material: Description of Material 9t2112021 GBI 14s TP-I SILT(ML} Test Method ASTM D698A 140 135 TEST RESULTS Maximum Dry Density 108.0 PCF Optimum Water Content 15.5 o/o 130 125 GRADATTON RESULTS (% PASSTNG) #200 #4 3t4" 90 100 100 (Jo.tÞ ïnz uJo É.o ATTERBERG LIII'IITS 1 20 LL PL PI 27 22 5 11s Curves of 100% Saturation for Specific Gravity Equalto: 110 2-80 2.70 2.60 105 100 95 90 5 15010 WATER CONTENT o/o 20 25 30