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Home My WebLink AboutSubsoil StudyLI(P Engineering, fnc. qVII./GEOTECHNICAL SOIL AND FOUNDATION INVESTIGATION F'OR A MAIN RESIDENCE AND BARNiADU 4C RANCH GARFTELD CREEK ROAD, CR #312 NE\il CASTLE PIN 218334300058 GARFTELD COUNTY, COLORADO PROJECT NO. 22-3661 MAY 31,2022 REVISED AUGUST 8,2022 PREPARED FOR: BRENT SCOTT P.O. BOX 55s9 EAGLE, CO 81631 Br,ent. S cott@moun@inbevera ge. com P.O. Box 724,Eagle, CO 81631 Tel. (970) 390-0307 www.LKPEneineering.com TABLE OF CONTENTS EXECUTIVE SUMMARY ........... SCOPE OF STUDY SITE DESCRIPTION. PROPOSED CONSTRUCTION FIELD INVESTIGATION SUBSURFACE SOIL AND GROUNDWATER CONDITION FOUNDATION RECOMMENDATION S SLAB CONSTRUCTION CRA\ML SPACE RETAINING TVALLS UNDERDRAIN SYSTEM... SITE GRADING AND DRAINAGE LAWN IRruGATION.,......... LIMITATrON................ FIGURES LOCATION SKETCH ..... AREA MAP. 2 2 2 3 3 J 4 5 6 6 6 7 7 I SUBSURFACE EXPLORATION LOGS. ...DRAWING NO. 1 ..DRAWINGNO.2 .FIGURE NO's 1-3 .FIGURE NO. 4GRAIN.SIZE DISTzuBUTION. PERIMETER DRAIN DETAIL. STRUCTURAL FILL WITH GEOGRID ,..FIGURE NO. 5 .....FIGURENO.6 OVEREXCAVATION AND COMPACTION...-,... ."..........FIGUR8 NO. 7 P.O. Box 7Z4,Eagle,CO 81631 Tel (970) 390-0307 www.lkpengineering.com EXECUTIVE SUMMARY The proposed bamlresidence should be supported with conventionel type spread footings, designed for an allowable soil bearing pressure of 1500 psf. They should constf,uct the footings on the undisturbed silty to sandy clay to silty-clayey sand with cobbles and boulders or on geogrid improved structural fill. See Foundation Recommendations. SCOPE OF'STUDY This report presents the results of a subsurface Soil and Foundation Investigation for a proposed single-family residence and a barn with an apartment at4C Ranch, New Castle, County Road 312, PIN 218334300058, Garfield County, Colorado. The purpose of the subswface soil and foundation investigation was to determine the engineering characteristics of the foundation soil and to provide recommendations for the foundation design, grading, and drainage. Geologic hazard studíes are outside of our scope oJ'services. SITE DESCRIPTION The 4C Ranch is 1163.959 acres property, south of New Castle, Garfìeld County, Colorado. The proposed building sites are located in the northwest portion of Section 3, as shown on the area map, drawing 2 and on the Location Sketch, Drawing L The building sites tÌrr the proposed barn/residence are on meadows. Vegetation within the proposed building site LKP Engineering,Inc, 4J consisted of grass. The topography within the selected building areas (where the test pits were excavated) is relatively flat.Drainage is to the north and northwest. Garfield Creek and Garfield Creek Road are to the north of the proposed building sitc for the main residence. The area was surrounded by mountains. PROPOSED CONSTRUCTION W'e understand that the proposed main residence will be fwo story, wood frame construction without a basement, on a concrete foundation, and the bam building will also be two story wood frame construction with an apartment above on one side, and a large barn on the other. We anticipate loads to be light, typical of residential construction. If the finalized plans differ significantly from the above understanding, they should noti$r us to reevaluate the recoûlmendations of this report. FIELD INVESTIGATION The field investigation, conducted on May 25,2022, consisted of logging and sampling three test pits. Approximate locations of the test pits are shown on Drawing No. l- We show the soil profile of the test pits on the Subsurf¿ce Exploration Logs, Figure No's 1 through 3. Soil samples for laboratory soil anaþsis and observation were taken at selected intervals. We understand that your excavator dug the test pits prior to our site visit. SUBSURFACE SOIL AND GRCIUNDTVATER CONDITION The soil profiles encountered in the three test pits were fairþ uniform, consisting of 2 to 5 feet of topsoil over brown to light brown, silty-sandy clay to silty-clayey sand, gravelly with cobbles and varying amounts of boulders. Moishue content was high (15 to 17%) but free P.O. Box 724,Eagle, CO 81631 Tel. (970) 390-0307 wwlv.LKPEngineering.com 4 ground water or bedrock were not encountered in any of the test pits. We sampled the soil in the test pits at random intervals. The samples were tested for natural moisture content and grain-size distribution. The test results are shown on Figure numbcr 4. FOUNDATION REC OMMENDATIONS The proposed main residence and the barn with an additional dwelling unit, should be supported with conventional type spread footings, designed for an allowable soil bearing pressure of 1500 psf. They should construct the footings on the undisturbed silty to sandy clay to silty-clayey sand, gravelly with cobbles and some boulders. If unsuitable soils (thick layers of topsoil) are encountered within the foundation excavation, the proposed residence and the additional dwelling unit should be supported with conventional fype spread footings constructed on ø structuralfll, designed for a maximum allowable soil bearing pressure of 2000 psf. The footings will be placed on overexcavated aryd corwcted,.stqucturql..fr-ll improvedwith three (3,) la:¡ers of Tensør, Triaxial-Geogrid, as shown on the attached detail, Structural Fill with Geogrid, Figure No. 7. Minus 3-inch road base or other approved, imported structural material, free from topsoil, organics and volcanic ash, can be used as a structural filI. A minimum of four feet of the unsuitable subgrade material (topsoil or other soft or wet soils) should be overexcavated uncler the entire foundation. The width of the overexcavation should be according to the attached overexcavation and compaction detail with a minimum of five feet on the outside perimeter of the excavation. The completedfoundation excavation should be observed and/or tested by the wtdersi.gned engineer to verify that the soil conditions encountered durtng construction are ds anticipated ín this report. We recommend a minimum width of 16 inches for the continuous footings and? feet for the isolated footing pads. Continuous foundation walls should be reinforced top and bottom to span an unsupporfed length of at least 10 feet. The proposed fbundation should be set at a minimum depth of four feet below the fînished grade or at the minimum depth required by the local building code. The foundation P.O. Box 724,Eagle, CO 81631 Tel. (970) 390-0307 www.LKPEngineerins.com 5 excavation should be free from excavation spoils, frost, organics and standing water. 'We recommend prooÈrolling of the foundation excavation. Soft spots detected during the proof- rolling, should be removed by overexcavation. Any overexcavation within the proposed foundation should be backfilled, in I inches loose level lifts and compacted to 100% of the maximum dry density and within 2 percent of the optimum moisfure content as determined in a laboratory from a Standard Proctor test (ASTM D-698). A structural fill, placed under footings shoulcl be tested by a qualified professional, SLAB CONSTRUCTION The natural on-site soils, exclusive of topsoil and organics, are suitable to support lightly loaded slab-on-grade construction. In the event that the thick topsoil layer is also encountered under the proposed slab on grade areas, the unsuitable soil should be overexcavated and replaced with a non-swelling, structprqlfrll, reiryforced with lat¡ers of Tensør .Geogrid, as described above in the foundation recommendations section. The subgrade for the slab-on-grade construction should be proof compacted to detect and remove soft spots. They should backfill overexcavated soft spots and other underslab fill with the on'site soil, free from topsoil and organics, or other suitable material, compacted to a minimum of 95 percent of the maximum standardProctor density (ASTM D-698). Suitable material should be free from topsoil, organics and rock fragments greater than 3 inches. The concrete slab should be constructed over a 4-inch layer of clean gravel consisting of -314-inch gravel with at least 50% retained on the No. 4 sieve and less than 3 percent passing the No.200 sieve. They should reinforce the concrete slab-on-grade and score controljoints according to the Arnerican Concrete Institute requirements and per the reçornmendations of the designer to reduce damage due to shrinkage. The concrete slab should be separated from the foundation walls and columns with expansion joints to allow for independent movement without causing damage. P.O. Box 724,Eagle, CO 81631 Tel. (970) 390-0307 www.LKPEngineerine.com 6 CRAWL SPACE If topsoil is encountered in the crawl space al€as, it should be overexcavated and replaced with non-organic soil. Thc organic matter contained in the topsoil will decompose with time releasing odors (like row sewage) that might not be acceptable by the homeowner. Crawl spaces should be vented according to the building code. RETAINING WALLS Foundation walls retaining earth and retaining structures that are laterally supported should be designed to resist an equivalent fluid densify of 60 pcf for an "at-rest" condition. Laterally unrestrained structures, retaining the on-site earth, should be designed to resist an equivalent fluid density of 40 pcf for the "active" case. The above design recommendations assume drained backfill conditions and a horizontal backfill surface. Surcharge loading due to adjacent stnrcftues, weight of temporary stored construction materials and equipment, inclined backfill and hydrostatic pressure due to undrained backfill should be incorporated in the desigu. They should try to prevent the buildup of hydrostatic pressure behind the retaining wall. Passive earth pressure of360 psfcan be used for the lateral pressure against the sides of the footings. Resistance to sliding at the bottom of the footings can be calculated based on a coefficient of friction of 0.5. Undisturbed soil or a structural fill compacted to 100 percent of the maximum dry density and within 2 percent of the optimum moisture content will be used to resist lateral loads at the sides of the footings. UNDERDRAIN SYSTAM To reduce the risk of surface water infiltrating the foundation subsoil, we recommend installation of a fbundation perimeter drain (see Figure No. 5). The foundatíon perimeter drain should consist of a 4-inch diameter, perforated pipe, sloped to a suitable gravity outlet, at a 114 P.O. Box 724,Eagle, CO 81631 Tel. (970) 390-0307 www.LKPEngineering.com 7 inch per foot for flexible or at a 1/8 of an inch for rigid pipe. The bottom of the trench adjacent to the footing should be lined with a polyetþlene moisture barrier glued to the foundation wall. The drain pipe should be covered with a minimum of 6 inches af -3/4-inch free-draining granular material. Geotextile (Mirafi 140N or equivalent) should be used to cover the free- draining gravel to prevent siltation and clogging of the drain. The backfill above the drain should be granular material to within 2 feet of the ground surface to prevent a buildup of hydrostatic pfessure. STTE GRADING AND DRAINAGE The following recommendations are general, Exterior backfill should be compacted at or near the optimum moisture content to at least 957o of the maximum standard Proctor density under pavement, sidewalk and patio areas and to at least 90% of the maximum standard Proctor density under landscaped areas. They should use mechanical methods of compaction. Do not puddle the foundation excavation. The site surrounding the building structure should slope away from the building in all directions. A minimum of 12 inches in the first 10 feet is recommended in unpaved areas, and three inches in the first 10 feet in paved areas. The top of the granular foundation backfill should be covered with a minimum of I foot of relativeiy impervious fill to reduce the potential of surface water infiltrating the foundation subsoils. Surface water natrually draining toward the proposed building site should be diverted around and away from it by means of drainage swales or other approved methods. The roof drains and downspouts should extend and discharge beyond the limits of the backfill. LAWN IRRIGATION It is not recommended to introduce excess water to the foundation soils by installing sprinkler systems next to the building. The installation of the sprinkler heads should ensure that the spray from the heads will not fall within 10 feet of foundation walls, porches or patio slabs. P.O. Box 724,Eagle, CO 81631 Tel. (970) 390-0307 www.LKPEngineering.com I Lawn inigation mustbe controlled. LIMITATION This report has been prepared according to locally accepted Professional Geotechnical Engineering standards for similar methods of testing and soil conditions at this time. The type of soil testing was selected by the ovrner as the preferred method for the soil and foundation investigation over a soil and foundation investigation with a drill ng. There is no other warranty either expressed or irnplied. The findings and recoürmendations of this report are based on field exploration, laboratory testing of samples obtained at the specific locations shown on the Location Sketch, Drawing No.1 and on assumptions stated in the report. Soil.conditions at other locatigns may vary. which m4y,Oot begome evident until 1þ-e,.fouqdation excqvation is coryplqtgd. If soil or water conditions seem different trom those described in this report, we should be contacted immediately to reevaluate the recofirmsndations of this report. '!V'e are not responsible for technical interpretation by others of the data presented in this report. This report has been prepared for the exclusive use of Brent Scott, for the specific application to the proposed Main Residence and Bam with an ADU at 4C Ranch, New Castle, County Road 312, PIN 218334300058, Garfield County, Colorado. Sincerely, LKP ENGINEERING,INC. t''\ i¡ìjj.ìi!,1i LuizaPetrovska, PE J :\_WP X4-LKPV022U2 -3 60 6CLAY-PITS. DOCX P.O. Box 724,Easle, CO 81631 Tel. (970) 390-0307 wyvw.LKPE¡rgine.-e_ring.cogr NOTE: THE LOCATION OF THE TEST PITS lS APPROXIMATE. IT IS NOT BASED ON A SURVEY crvrL/GEolEcHNrcAL Engineering, Inc. P.O. Box 724, Eogle, CO 81631 Tel (97O) 390*0307 www.LKPEngíneering.com LKP LOCATION SKETCH 4C RANCH CR 312, NEW CASTLE PIN: 218 334 3000 58 GARFIELD COUNry, COLORAÐO PROJECT NO.: 22-3619 SCALEi DMWNGNO.: 1 +TS5 #:)i3!3 f'{: ql ffi$å.:5T¡J 'l"t ç IT8$UTI $rr {i ftfti 'Jj' 'i:¿: i rll,r:l'rl. TdiÊ Fì$'i q,ï Tes åtsr']ifuÌ 'li.¡i' Ël{}!lJ'i¡ ,-,1 t i.|.\; ,:}P {: Ë.L/-r. iti¡'l'r¡d rr-ì,7t å"t'iäi't'{d r ! o.à lf5 fì613W i ¡t¡rllilrlþ_, af .--¿ i::,jr r i ' T¡]i tìf 'li{J .t-fj$ Êl'x!!3 'l'$;'i R$*1tr l¡¡¡..¡ç=::::F ={J 1 2ntì NOTE: THE LOCATION OF THE TEST PITS lS APPROXIMATE, IT IS NOT BASED ON A SURVEY cMrlçEoTECIINICAI Engineering, Imc. P.O. Box 724, Eogle, CO 81631 Tel (970) 390-0307 www.LKPEngineer¡ng.com LKP AREA MAP 4C RANCH CR 312, NEW CASTLE PIN: 218 334 3000 58 GARFIELD COUNTY, COLORADO PROJECT NO,:22-3619 scALE: -1"=Bo' DRAWING NQ.:.2 DATE OBSER\ED: Moy 25,2022 ELEVATION: Test PÍt-t/ProtÍhe Hole-t ItaÍn frouse DEPTH FEET .s Y M B o L s A M P L E DESCRFNON OF MATERIAL AND SAIIPLE LOCANON UBORATORY TãST RE.'U¿rs REMARKS 5 _10 _f5 t0 Topsoil, thickness varies from 2 to 5 feet Brown, cla¡ælrgrovelly sond wîth cobbles ond boulders MC=í5.1i Light brown, sandy clay motrix with cobbles ond boulders -2OO=J5.61 Bottom of Test Pit @ 7.ı feet No Ground Woter Encountered I,EGEND: tr T DD MC - Z-lnch O.D. Callfomia Lînar Sample- Eulk Samplc - Noturql Dry Denslty (pcf) - Natural Molsture Content (x) S/eæ-2O0 - Perccnt Passlng No. 200LL - Llquld LlmitPl - Plostlclty lndexOW - Qround votçr IJ(P ENGINEERING, INC.SUBSUNFACE EXPI,ORATION LOG Ffrüæf Iø!22-J619 IfløÆflq,, DAIE OBSER\ED: Moy 26,2A22 ELEVATOT'I: Teet, Plt-?Ifain Ilouse DEPIH FEET s Y M B o L s A M P L E DESCRIPNON OF MA'IERIAL AND SAMPLE LOCANAN LABORATORY TEST RESULïS REMARKS 5 -lo -1ü _20 Å Topsoil, thicknees varies from 2 to 4 feet LÍght brown, motrÍx wlth boulders silty-sondy clay cobbles and large Bottom of Test P¡t @ 6.5 feet No Ground Water Encountered I.EGEND: t]t DD MC -200u PI GW - 2-lnch O.D. Callfomla Llner Sample - Bulk Sample - Naturql Dry Denslty (pcf) - Natural Molsture Content (fr) - Pereant Paeslng No, 200 Slaw - Uqufd Llmlt - Plastîcìty lndex - Ground watar I,KP ENGINEEMNG, INC.SUBST'BFACE HTPTORA1TON IOG mqãçt tfr t 22-3619 2FIølæ NO.: DATE OBSER\ED: Moy 25,2022 ELEVATON: Test PÍt-fl Barn-AIIU DEPTH FEET s Y M B o L .9 A M P L E DESCHPNON OF NATERIAL AND SATIPLE LOCANON LABORATORY EST RESU¿TS RETIARKS 5 _10 - t5, _20 I Topsoil, thickness vor¡es from 2 to 4 feet Light brown, motrix with boulders silty-sandy cldy cobbles and large Bottom of Test P¡t AÐ 7 feet No Ground Water Encountered I.EGEND¡ t]I DD MC -200 LL PI êw - 2-Ínch O.D. Callfornla Llner Sampla - Bulk Sample - Naturql Dry Ðenslty (pcf) - Natural Moleture Contant (E) - Parcent Paaslng No. 20O Slave - Llquld Llmît* Plaetlcîty lndax* Ground watdr IJ(P NNGINEDRING, INC.SUBSURFACD E¡(PTORATION TOG Fnøñf 'dlr:22-36t9 FtcÆNo,t J ì$Bo$sIs)$IaNeU,)dUqIo=àFROt'l: Test PÍt I at 5 feetU.S' SrrrûDtnD trrf æE¡mrc rrv fìlC#S US STÁI,IDARD gEtf ,!üldæçS6 43 zttê I *t tûÐ J I 6 8lO tl ,6 ã, &r¿Xr5070|OO14O2O0H'ffiÆER090'to203AIo40È50Ëðq60 .b\"ì7098090EO70Iä60I350q€roñS¡onro,ao10a5CIOrco 50105'î 0.50,'t o.o5o.ao50.o01Sand: 35.6tFfines: 35.62\\ìI\\Sllt or ClaySondfînemedíumcoars€GrovdfrnecoctrseCobblesMolsture Content: 15.48Craval: 28.7ßDescrìptlon: Brown, sÍlt¡-clayey, gravelly eend .t. A Þ !! S ð R=-( :JÕl.- Þ Þ Þ À Þ' Þ AWAY FROM BUILDING BACKFILL WITH A MINIMUM OF ONE FOOT OF RELATIVELY IMPERVIOUS SOIL FABRIC (MIRAFI 140N OR EQUTVALENT) 3/4.INCH DIAMETËR, COARSE, CLEAN CRUSH ROCK 30 MIL MINIMUM THICKNESS,DIAMETER PERFORATED PIPE SLOPED TOPLASTIC LINER, GLUED TO A DAYLIGHT LOCATION AWAY FROM THE FOUNDATION AT 1/4INCH PER FOOT FOR FLEXIBLE AND 1/8-INCH MINIMUM FOR RIGID PIPE FOUNÐATION WALL cryIL/cEoTEcHNrCÀI, Engineering, Inc. P.O. Box 724, Eoglo, CO 81631 Tel (970) 390-0307 www.LKPEngìneering.com LKP PERIMETER DRAIN 4C RANCH CR 312, NEW CASTLE PIN:218 334 3000 58 GARFIELD COUNTY, COLORADO PROJECT NO.:22-3619 scALL: N.T.s. 5 FIGURE NOi î 2 FROsT DEPTH COTIPACTED FILL FOOnN6 I 2 FOR C,QN,nNUOUS FQOnNq d : DEPTH TO ADEOUATE BEARING MA|ERALd:2xþ tüilcHEWR /S ¿Ê'SS SOUAE€ FQONNG d : DEPTH TO ADEQUATF BEARINê MÅTER|ALd*l-1/2xb tl,tilCHEWR /.S ¿ßS NOTî: Source of ìnformatÌon from Foundations and Eorth Structures, Design Manual 7.2 Deportment of the Nauy, Novol Focilitìes Engneering Commond LKP cnm,/cnomcENIca¡. Engineering, lnc. P.o. Box 724, Eqglo, CO 81631 Td (97O) 390-0307 wwv.LKPEnglncoring,com OVEREXCAVATION & RECOMPACTION 4C RANCH CR 312, NEW CASTLE PIN:218 334 3000 58 GARFIELD COUNTY, COLORADO 22-3619 /vrs 6 FOOTING ,| 1 I ¡" .j '.;.... Þ't:b À JÞ , Tv¡ Þ. I .: , .:.r i'. r .) "'. É l¡.1È J-Þô- u¡o t--U'o É.IL ulff,o C)J (JoJ 5'min 6" max. 6" min. SOFT (or Uneuitable) BEARING SO TENSAR TRIAXIAL GEOGRID MINUS 3.INCH ROAD FOR STRUCTURAL FILL PLACEMENT OVEREXCAVATE 4 FEET BELOW THE FOOTINGS AND 3 FEET BELOWTHE SLAB ON GRADE cIVII,/GEorlcÍMcå¡, Engineering, fnc. P,O. Box 724, Ëagle, CO 81631 Tel (970) 39G0307 www.LKPEngln€er¡ng.æm LKP GEOGRID REINFONCW¡ STRUCTURAL FTTI. 4C RANCH CR 312, NEW CASTLE PIN:2f I 334 3000 58 GARFIELÐ COUNTY, COLORADO 22-3619 scALE: N.T.s. 7 L'RAwlNt; NU.: