Loading...
Report (161) RECEIVED . JUL 1 0 201? BUCIIITY, Geotechnical Report 12000 SW Viewcrest subdivision Tigard, Oregon Prepared for: Chris Eschman 21 May 2015 12244 RE GON , , ' EU`t' EXPIRESu SOilSOLlitiOnS..y f Rapid LLC 3915 SW Plum Street Portland, OR 97219 503-816-3689 TABLE OF CONTENTS 1.0 GENERAL INFORMATION 3 2.0 SITE CONDITIONS 3 2.1 Surface Conditions 3 2.2 Regional Geology 4 2.3 Field Explorations and Surfaces Conditions 4 2.3.1 Field Explorations 4 2.3.2 SubSurface Conditions 5 2.3.3 Groundwater 5 3.0 GEOTECHNICAL DESIGN RECOMMENDATIONS 5 3.1 Foundation 5 3.2 Floor Slabs 6 3.3 Seimic Design 7 3.4 GeoHazard Review 6 3.5 Pavement Design 7 4.0 CONSTRUCTION RECOMMENDATIONS 8 4.1 Site Preparation 8 4.1.1 Proof Rolling 8 4.1.2 Wet Soil Conditions 8 4.1.3 House Demolition and site clearing 8 4.2 Excavation 8 4.3 Structural Fills 9 4.3.1 Native Soils 9 4.3.2 Imported Granular Fill 9 4.3.3 Pavement Base Aggregate 9 4.4 Drainage Considerations 9 5.0 CONSTRUCTION OBSERVATIONS 10 6.0 LIMITATIONS 10 SUPPORTING DATA Appendix A-Figures Figure 1 Location Plan Figure 2 Tax map Figure 3 Survey Figure 4 Site plan with testing locations Appendix B—Soil Logs and Laboratory data SW View Crest subdivision 2 5/21/2015 1.0 PROJECT AND SITE DESCRIPTIONS Rapid Soil Solutions(RSS)has conducted this geotechnical investigation at the subject site with the street address 12000 SW Viewcrest Court, Tigard, Oregon, for the proposed 7-lot subdivision. This parcel is located within the City of Tigard,near the southwestern edge of the city limits and within the southeast quarter of Washington County. Located on the northern side of SW Aspen Ridge Drive approximately 0.26 miles beyond its intersection with SW Bull Mountain Road. The flag shaped lot has a narrow protrusion from the northeastern corner of the lot,which connects the parcel to the cul-de-sac terminating SW Viewcrest Court. This cul-de-sac is approximately 0.08 miles beyond the initiation of SW Viewcrest Court on the western side of SW Aspen Ridge Drive. This is 0.34 miles west of SW Pacific Highway, 0.09 miles south of SW Bull Mountain Road, 0.19 miles north of SW Beef Bend Road and 1.29 miles north of the Tualatin River. The site is located within the Aspen Ridge subdivision, designated Lot 19. It is situated in the Southwest Quarter of the Northwest Quarter of Section 19, Township 2-South, Range 1- West W.M. and can be distinguished by state parcel identification number 2S110BC01700, alternate account number/r-number R2028585 and PortlandMaps Property ID W254307. The latitude and longitude of the site are 45.4121903 and- 122.801302 respectively. See Appendix A, Figure 1 for site location indicated on a portion of a USGS 7.5 minute topographic map. Subsequent figures include additional site location information. 2.0 SITE CONDITIONS 2.1 Surface Conditions The subject site is located on a generally southeast facing slope on the eastern edge of Bull Mountain. The site is located roughly 30'below the local high point along SW Bull Mountain Road northwest of the subject site. The slopes on this hillside, starting at the subject site and continuing down slope to SW King George Drive, are mapped as typically falling between 10% and 25%, with occasional steeper portions. After which these slopes decrease to generally less than 10%until they termination at the Tualitain River. A portion of the southern edge of the subject site is mapped with slopes over 25% and the entire site, with the exception of the northwest corner is mapped as containing greater than 10% slopes. The steepest areas on the subject site are located directly next to the Emergency Vehicle Turnaround Easement located in the southeastern corner,where the slopes were cut to create a level area on the hillside for the turnaround. Alder trees and other vegetation stabilize this slope. The site is currently occupied by a single-family residence constructed in 1975. This 3,892 square foot spiral-shaped residence is located in the northwestern portion of the 67,518 square foot(1.55 acre)lot. North of the home, and along the narrow eastward access protrusion,there is a graveled driveway. Under the covered portion of the driveway, the subgrade material changes to concrete. South of the existing residence is a concrete patio and a pool surrounded by a wooden deck. The slopes to the south and the east of the residence were covered in tall grasses, while the landscaping directly around the home contained larger bushes and trees.No running or standing water(with the exception of that found within the pool) as observed on the subject site. SW View Crest subdivision 3 5/21/2015 The site is surrounded on three sides by single-family residence with lots ranging in size from 0.14 to 0.34 acres. The parcel adjacent to the western edge of the subject site is a 4.87 acre parcel containing a single residence at the northern end, zoned R-6(subject property is zoned R-4.5)and is not part of the City of Tigard, instead falling under the jurisdiction of Unincorporated Washington County. At the time of the site visit, RSS observed that the portion of this parcel adjacent to the property contained tall grasses and slopes that approximately matched those found at the subject site. Some level areas on the site,particularly those around the southern end of the residence, appear to have been artificially cut or filled to create an artificially level area. If the area does contain fill, it may be non-structural and may require removal. 2.2 Regional Geology Current geologic literature1'2 classifies the slopes below the project site as part of the Columbia River Basalt Group. This group is a thick accumulation of flood basalts was produced by dozens of fissure eruptions in eastern Oregon and Washington in the middle Miocene. These dark grey to black basalts can be divided into 8-10 distinct Columbia River Basalt flow types, comprised of as many as two dozen individual flows. They present in the region both as weathered and unweathered flows and contain interflow zones of breccia, ash and baked soil. Unweathered materials are typically blue-black, dense and finely crystalline basalt with massive columnar to close cubic jointing. The weathered flows are reddish-brown to gray-brown, crumbly to medium dense basalt. The regional climate typically produces a thick layer of colluvium, composed of windblown silts(loess) and sand, clay and rock fragments produced from the breakdown of the bedrock units,that overlies the Columbia River Basalts. The slopes in the region are not mapped as including this surficial layer,but likely have at least a thin accumulation of loess and colluvium. In areas with steep slopes and thicker sediment accumulations, heavy rainfalls, small landslides and gravity can move these surficial materials downslope. 1 Ma,L.,Madin,I.P.,Duplantis,S.,and Williams,K.J.,(2012),Lidar-based surficial geologic map and database of the greater Portland, Oregon,area, Clackamas, Columbia,Marion,Multnomah, Washington, and Yamhill Counties, Oregon,and Clark County, Washington:DOGAMI,Open-File Report 0-2012-02, scale 1:8,000. 2 Schlicker,H.G.and Deacon,R.J., 1967,Engineering geology of the Tualatin Valley region:Oregon Department of Geology and Mineral Industries,Bulletin 60,scale 1:48,000. SW View Crest subdivision 4 5/21/2015 respectively. The bottom of exterior footings should be at least 16 inches below the lowest adjacent exterior grade. The bottom of interior footings should be at least 12 inches below the base of the floor slab. Footings placed on engineered fill or firm native sub-grade should be designed for an allowable bearing capacity of 2000 pounds per square foot(psf). The recommended allowable bearing pressure can be doubled for short-term loads such as those resulting from wind or seismic forces. Based on our analysis the total post-construction settlement is calculated to be less than 1 inch,with differential settlement of less than 0.5 inch over a 50-foot span for maximum column,perimeter footing loads of less than 100 kips and 6.0 kips per linear foot. Lateral loads on footings can be resisted by passive earth pressure on the sides of the structures and by friction at the base of the footings. An allowable lateral bearing pressure of 100 pounds per cubic foot(psf/f)below grade may be used. Adjacent floor slabs, pavements or the upper 12-inch depth of adjacent,unpaved areas should not be considered when calculating passive resistance. An angle of internal friction of 32 degrees can be used. If construction is undertaken during wet weather, we recommend a thin layer of compacted, crushed rock be placed over the footing sub-grades to help protect them from disturbance due to the elements and foot traffic. 3.2 Floor Slabs Satisfactory sub-grade support for building floor slabs can be obtained from the native sub- grade prepared in accordance with our recommendations presented below. A 6-inch-thick layer of imported granular material should be placed and compacted over the prepared sub- grade.Imported granular material should be crushed rock or crushed gravel that is fairly well graded between coarse and fine,contains no deleterious materials,have a maximum particle size of 1 inch,have less than 5 percent by weight passing the U.S. Standard No. 200 Sieve, and meet OSSC 02630.10—Dense Graded Aggregate 1"-0".The imported granular material should be placed in 6-inch-thick lifts and compacted to at least 95 percent of the maximum dry density as determined by American Society for Testing and Materials(ASTM)D 1557.A sub-grade modulus of 125 pounds per cubic inch(pci)maybe used to design the floor slab. Installation of a vapor barrier is required for all the houses built on this lot.It will reduce the potential for moisture transmission through, and efflorescence growth on, the floor slabs. Additionally, flooring manufacturers often require vapor barriers to protect flooring and flooring adhesives and will warrant their product only if a vapor barrier is installed according to their recommendations. The selection and design of an appropriate vapor barrier, if needed, should be based on discussions among members of the design team. SW View Crest subdivision 6 5/21/2015 3.3 Seismic Design Criteria The seismic design criteria for this project found herein is based on the OSSC 2012, Section 1613 and from the USGS Earthquake Hazards Program. A summary of IBC 2012 seismic design criterion below: using a Lat of 45.4122 and Long of-122.8013 Short Period 1 Second Maximum Credible Earthquake Spectral Acceleration Ss=0.96g S1 =0.42 g Adjusted Spectral Acceleration Sms= 1.07 Sml =0.66 Design Spectral Response Acceleration Perimeters Sds=0.71 Sd1=0.4 3.4 GeoHazard Review The Oregon HazVu: Statewide Geohazard Viewer3 was reviewed on May 15,2015 to investigated mapped geological hazards. This review indicates that the project site is situated outside the 100-year floodplain. The expected earthquake-shaking hazard is classified as 'very strong' with no mapped earthquake liquefaction hazard. The nearest mapped active fault is the NW-SE oriented Molalla-Canby fault, located approximately 1.15 miles northeast of the subject site. Additional fuals are mapped running parallel to SW Pacific Highway, approximately 0.34 miles east of the subject site. IMS-154 rates the site vicinity as having a peak horizontal acceleration of 0.4 to 0.5g for a magnitude 6.8 Portland Hills Fault earthquake, which would result in severe shaking and capable of producing slight damage in specially designed structures, considerable damage in ordinary substantial buildings with partial collapse, and great damage in poorly built structures.No landslides are mapped on or in close proximity to the subject site. The nearest mapped landslides are small earth flows associated with the banks of drainages on the northern and northeastern slopes of Bull Mountain. 3.5 Pavement Design Our pavement design recommendations are based on the SILT, 8"of 1 %2"minus rock with 2"of 3/4"minus rock. Compaction standards on all future streets require 92%of ASTM D1557. Asphalt thickness will be 4". The asphalt's base rock section is not intended to serve as a construction working surface. Oftentimes such use will result in contaminated bas rock and a soil sub-grade which has become disturbed. 3 http://www.oregongeology.org/hazvu/ 4 Wong,I.,Silva,W.,Bott,J.,Wright,D.,Thomas,P.,Gregor,N.,Li,S.,Mabey,M.,Sojouner,A.,and Wang,Y.,(2000),Earthquake scenario ground shaking map for the Portland, Oregon, metropolitan area: Portland Hills Fault M 6.8 earthquake,Peak horizontal acceleration(g)at the ground surface:DOGAMI, IMS-15.Scale 1:62,500 SW View Crest subdivision 7 5/21/2015 • 4.0 CONSTRUCTION RECOMMENDATIONS 4.1 Site Preparation Demolition should include removal of existing improvements throughout the project site. Underground utility lines,vaults,basement walls or tanks should be removed or grouted full if left in place. I recommend that soil disturbed during grubbing operations be removed to firm,undisturbed sub-grade. The excavations should then be backfilled with compacted structural fill or native materials if it's within its optimum moisture content. 4.1.1 Proof Rolling Following stripping and prior to placing aggregate base course,pavement the exposed sub-grade should be evaluated by proof rolling. The sub-grade should be proof rolled to identify soft, loose, or unsuitable areas. Please give 24 hour notice to observe the proof rolling. Soft or loose zones identified during the field evaluation should be compacted to an unyielding condition or be excavated and replaced with structural fill, as discussed in the Structural Fill section of this report. 4.1.2 Wet Weather Conditions The near-surface soils will be difficult during or after extended wet periods when the moisture content of the surface soil is more than a few percentage points above optimum. Soils that have been disturbed during site preparation activities, or soft or loose zones identified during probing or proof rolling, should be removed and replaced with compacted structural fill. Track-mounted excavating equipment will be required during wet weather. The imported granular material should be placed in one lift over the prepared,undisturbed sub-grade and compacted using a smooth drum,non-vibratory roller. If construction is undertaken during the wet weather the builder may choose to cement treat the top 12"of sub-grade soil on the site. This will save time over the duration of the project due to the moisture sensitive silty CLAY becoming soft and yielding which will require repeated over excavation and replacement with structural fill. The geo-textile fabric can be eliminated if the sub-grade is cement treated. 4.1.3 Demolition and site clearing RSS will verify that the area has been stripped of all organic material prior or construction debris prior to placement of any fill. Only imported material shall be used to fill old basement area. See below section for import fill materials. Please allow 24 hours to schedule inspection for post demolition. 4.2 Excavation Subsurface conditions of accessible cleared areas of the project site show predominately silty SAND to SAND to a depth explored(10 feet). Excavations in the upper soils maybe readily accomplished with conventional earthwork equipment with smooth faced bucket. SW View Crest subdivision 8 5/21/2015 4.3 Structural Fills Fills should be placed over sub-grade prepared in compliance with Section 4.1 of this report. Material used, as structural fill should be free of organic matter or other unsuitable materials and should meet specifications provided in OSSC, depending upon the application. A discussion of these materials is in the following sections. 4.3.1 Native Soils Laboratory testing indicates that the moisture content of the typical for optimum moisture content of the soil required for satisfactory compaction. This is depending on the weather conditions at the time of excavation. Native soils can use ASTM D698 and 95%compaction is required. Please supply the engineer with a 5gallon bucket of material 48hours prior to any compaction tests required. Compaction tests are required every 500 cu feet of fill or every 1.5 feet of elevation. 4.3.2 Imported Granular Fill The imported granular material must be reasonably well graded to between coarse and fine material and have less than 5%by weight passing the US Standard No.200 Sieve. Imported granular material should be placed in lifts 8 to12 inches and be compacted to at least 92% of the maximum dry density, as determined by ASTM D 1557. Where imported granular material is placed over wet or soft soil sub-grades, we recommend that a geo-textile serve as a barrier between the sub- grade and imported granular material. Please supply the engineer with a 5gallon bucket of material 48hours prior to any compaction tests required. Compaction tests are required every 500 cu feet of fill or every 1.5 feet of elevation 4.3.3 Pavement Base Aggregate Imported base aggregate for roads and parking lots should be clean, crushed rock or crushed gravel. The base aggregate should meet the gradation defined in OSSC 02630.10—Dense Graded Aggregate 1 1/2"-0,"with the exception that the aggregate should have less than 5%passing a US Standard No. 200 Sieve. The base aggregate should be compacted to at least 92%of the maximum dry density, as determined by ASTM D 1557. Please supply the engineer with a 5gallon bucket of material 48hours prior to any compaction tests required. 4.4 Drainage Considerations The Contractor shall be made responsible for temporary drainage of surface water and groundwater as necessary to prevent standing water and/or erosion at the working surface. We recommend removing only the foliage necessary for construction to help minimize erosion. Slope the ground surface around the structures to create a minimum gradient of 2% away from the building foundations for a distance of at least 5 feet. Surface water should be directed away from all buildings into drainage swales or into a storm drainage system. SW View Crest subdivision 9 5/21/2015 5.0 CONSTRUCTION OBSERVATIONS Satisfactory pavement and earthwork performance depends on the quality of construction. Sufficient monitoring of the activities of the contractor is a key part of determining that the work is completed in accordance with the construction drawings and specifications. I recommend that a geotechnical engineer observe general excavation, stripping, fill placement, and sub-grades in addition to base. Subsurface conditions observed during construction should be compared with those encountered during the subsurface explorations. Recognition of changed conditions requires experience. Therefore, qualified personnel should visit the site with sufficient frequency to detect whether subsurface conditions changes significantly from those anticipated. 6.0 LIMITATIONS This report has been prepared for the exclusive use of the addressee, and their architects and engineers for aiding in the design and construction of the proposed development. It is the addressee's responsibility to provide this report to the appropriate design professionals,building officials, and contractors to ensure correct implementation of the recommendations. The opinions,comments and conclusions presented in this report were based upon information derived from our literature review, field investigation, and laboratory testing. Conditions between, or beyond, our exploratory borings may vary from those encountered. Unanticipated soil conditions and seasonal soil moisture variations are commonly encountered and cannot be fully determined by merely taking soil samples or soil borings. Such variations may result in changes to our recommendations and may require that additional expenditures be made to attain a properly constructed project. Therefore, some contingency fund is recommended to accommodate such potential extra costs. If there is a substantial lapse of time between the submission of this report and the start of work at the site; if conditions have changed due to natural causes or construction operations at, or adjacent to,the site;or,if the basic project scheme is significantly modified from that assumed,it is recommended this report be reviewed to determine the applicability of the conclusions and recommendations. The work has been conducted in general conformance with the standard of care in the field of geotechnical engineering currently in practice in the Pacific Northwest for projects of this nature and magnitude. No warranty, express or implied, exists on the information presented in this report.By utilizing the design recommendations within this report,the addressee acknowledges and accepts the risks and limitations of development at the site, as outlined within the report. SW View Crest subdivision 10 5/21/2015 I 49 Je •,' or u,,u a ,n. ,., . _ 60 J ,Aapi�c „.•- pO°' "- .SW CORYUS COURT t S , SW t e Pr* am Aro, •° 300 50 99 Cf) 19 J m ' p e,be . 5si 1 73 9 53 i GG 00 x M: �� tr a A A 9 0 D 2^{ 7/w' .reci waa� j9G0 R 9600 5 �. .. 2V / 'T m 003 041 rJ J L i S s limit. wan 00000 6 s3� H� T sos0 e MD r S Ifni ass Ma i 1I N 0 S' x600 cel rn t g ...... ° • ..........r ROAD SW BULL MOUNTAIN g • .................................:: t wn,n .. $ Z00 „;0 &,1600 i• 0300 s I '2 ioo e N °� 3. s 0 'Y F s j;' : 3 t ? .an= € -.•_.+1__, `�5. ELEMAR DRIVE WINTERVIEW a ,l 7: i2e0011000 yy 04\i\ 501' st 0 — r'.°c 4 0 Y 310 R in n 3 5$66005 51 a' 450023—I VL.1 en o T °= 11IL lool..1300 e,ncJ 'I',8 8 IT, �,e t 5 101 400 ° g e55 0, 's SW Ty gW VIEWCREST . „......., 600 4 v ' • O621/11/6 1111131;: 0 _N11; a4 e oo� $63 DOD DRIVE 23- / 4 io . ,, amu(' Lv1:17 1. L� e,00 s a ssoo kiabo ? f J sz �.n Nil S3 36,:. ' i _ all :0 as a.n 6300 C [[ _ too . 34 5 500 6600 Subject Site 'r ? L'I a .17 ? 29 '" :1)' l SW s23-73 '�e°�'° DRIVE ,� a'Po .4e ASPEN F 600 q 2300:I0;1NW 000 g 33 34 3s _CNN , , .. sak z,00 zzoo zoo a }d1'°. e„ 39 w;, 5 I I a Pr' a. 'C . i $ 1 a,.� x ab <l Figure 2: Subject site location on the Washington County Assessor Map of the SW 1/4 NW 1/4 of Section 10, Township 2S,Range 1W W.M. COSMO V GAS ININalkt SOON 964PACE )4" IElISDIG n., LOTS 1-18M I , 45-50 'alNo MIS EISENFM -. .1 I 'r Rs""No 17 SEE SHEET 2 13 va • 9N RNr sE e _ • I unn EAOdEM 14 FEE NO.02032475 \ I c EASFwFN r- , 46 .4 I � 18 \ 1 16 1 CD g \ W g., I I 'r4,N 4, • •• • I — 'A w _ or N Ar02••w L I/ Cp S 0,.,510 331.0 n �7 N � ---- 45^ 4. = 45 vd 5.SINEW Na , k S•W. VIEWCREST COURT R • 0 �� s1..7 'C'l9 I CP °'SAMOA. 00 191.10 uIir-./�,1t s 05-5O.'a. `. maz eo.w �� gl^ s I 4 eA•F SETTER EFSENENr `wpP'--1 qj• > g! Ar0120 00 v .>3 '*CA i 20 21 g W 22 e- 23 g 24 g W 10,25S.F. "' "' 44 CD (D 10.825 S.F. ^ :g 9.280 S.F. 280 S.F. t, 1 Rnrt O t C7 TM- 13,593 S.F. �.A� MATE ihmNr =g 9,165 S.F. ^ -^ ,y, 10,194 S.F. gi .` S. 19 R $ �' 61 9••P ° STORw OAVMLL MD ^ P_` I^^ F••F C4L N er,S., _/SEE NOTES. W EASflENr S IT 141.014,..:T4.154 s MIO'Srw •' Sar ti 2 67.524 S.F. 7 i SEE NOBS,ONER a (ANt41 _ P.a+ 7475 _ N'Sr I e-0. L N 0r18*� N ern. 1.000 S 00.00" 00.00 00.00 • +#1> E CP SAO " 0000 99.N 55� /' 20'414 0RNlN0E_ `• tir N erlr 200.ie1S1__-_ -- •i 'de's �7zos— �S� 2CEsz usENEi.> F I ^ 3 a 26 43 \ ;; - 31 q 8 3 >7 9 $_w 11,534 S.F. / • 12,047 S.F. I� °r1°�5'"' b 9,775 S.F. ' 9,775 S.F. L 30 s 28 §' 27 r� u'bo�W = 9,785 S.F. o' 10,210 S.F - 11,069 S.F. `°•A , I ^ Pr.Ey 9p$Ig 818 _ " 48 Eai,� I _'.1zE 2NSs PI' ,, s• -Ig t I s 42 - ! R TRACT•A• 5.8 �.m d Axeo \ ssm '55c53 \ \ 18,950 S.F. WI CD 1...so-sow i„ 14 _ o °i55 wan 1 CD RESERVES YON STREET PLR- — _ --L--_"5"..20.•025.09 _ '• ' Ii ,•'1+.0.01 `7 \\ \\..,�, STpbI gMWr4E ;=^I 2 Vl \ \i). AN0 9W RMI 4Mm — "°° 00W • ,399 g •S.W. ASPEN RIDGE DRIVE �" � � es.00 0.5.00 eeA" -5.A f\ d?,6EFSETAINT 'I ` a 00.99 3201 • 1.r:=N 41 `\\ '�' — 32 �z 33 § 34 sa g: " S.F.^ s, 22,935 ®�\\ �tv+ 'r ^ o R 0• - 9,394 S.F. a 9,350 S.F. -N 9.350 S.F. _ 35 >� 36 s§ 37 s 38 s- 40 *.A, • ,��`;>° $a 9,350 S.F. 9,350 S.F. - -3 e,- 39 gstow .. = ^ ^ 9,350 SF. - 9,350 S.F. -- i,. 12,352 S.F. '4-4e Nro swop soot gg q ^ t0,d32 S.F. p,010•440E EASITIENT C b , _ m ^ E' " E0'MATE STOW 6+ Bay 3/f V. • N 0,10.20.0 3]032 ..•,n.]1.'. ..'NE C,,• y 0000 ). �8 19009 a fl SHEET.\ _ 11 / / 1.110 INMAL POINT \T1 Mum Y • - •0/Ys. N Winn, 03022' e/�/p'IA •W/WE • ,51,)3 - 4/r Fes. I I•ENown NEWT 1 I _ I•tEp ENS.PLT w0. 7409 SW Tech Center Dr,#145 Tigard,OR 97223 phn:503-443-3799 fax:503-620-2748 • 503.443.3999 • RAPID SOIL SOLUTIONS 3915 SW PLUM STREET PORTLAND, OR 97219-6018 PROJECT: RSS2015 LAB SERVICES JOB NO: 15-5468 LOCATION: 12000 SW VIEWCREST CT WORK ORDER NO: N/A SAMPLE SOURCE: SEE BELOW DATE SAMPLED: 5/14/15 MECHANICAL SIEVE ANALYSIS GROUP SYMBOL,USCS(ASTM D-2487) Silt or SAND GRAVEL COBBLES Clay Fine Medium Coarse Fine Coarse Location&Depth I USCS I LL PI #200 #1001 #50 #40 #30 I #16 #10 #8 I #4 11/4"13/8" 1/2"I 3/4" 1" 1 1/4" 1 1/2"( 2" 3" 6" Lab# PERCENT PASSING BY WEIGHT HAl @2' 26 4 8110 HA3 @4' 27 6 8110 BORING DEPTH MC% HAI 2' 21.9 HA2 6' 29.3 HA3 4' 29.8 HA4 6.5' 27.4 REVIEWED BY DE/is 1 HA#1 Surface Elevation:451 y 4e .0,6 ,0 eJe �4" a04e Boring Date:5114115 0 ti'c e -0 , �G Q� pec Boring Location:Tigard,OR j 0441." .0 0 00 0, �� Drilling Method:Hand Augur 0 > > > TP Top Soil - < < < N Yz > ><, 1 t><>l' a - 0-1 e g - ML Damp,tan brown,medium stiff,SILT g _ 3 i—2 P1=4, PL=26 21.9 ML End of hand augur hole at 2ft b N - f O I- I- 1 ft —5 1 m o _ fi6 - h _ —7 LOG OF BORING 12000 SW ViewCrest Road Rapid Soil Solutions Chris Eschman Plate: 1 1 ' . HA#2- / / 7 Surface Elevation:447 0 '6 i tt41' ,-"' Sib \ 4). / 4.- ' /AD Boring Date:5/14/15 Boring Location:Tigard,OR 4* /47/ / Drilling Method:Hand Augur 0 (-: . -7-- .. I '‘ 4 GP ' Fill materails consisting of gravels,sands •ihpi 40.- - 1 ieli r4riti 8, i 1 ,•s# *a- , •I 4 1 U - ii , 46 IIN .14, 1 4 ' II. I i .1 ML Damp,tan brown,stiff,SILT s - 3 i 0' -2 a- a v 1 8 It- I I:II ML-FL Damp,medium brown,medium stiff,fill that is silty mater als ;- 1 ill but not compacted in. ._3 .:.:. ; , 1111i tili1 1 t , 111 1:1:1 ix. .„. e ::.„ 1 j 4 : 1 ci i li ' :::::: U. re. ,-- --5 1 --6 ML Damp,tan brown,stiff SILT 1 , i ; ' I i 1 i I 1 1 1 - 1 if, h 1.: 29.3 Boring completed at depth of 6ft ,--- Z u 4 L -7 1 LOG OF BORING 1 12000 SW ViewCrest Road , Rapid Soil Solutions Plate 1 i 1 Chris Eschman i i 1 , HA#3 / / ' /' Surface Elevation:438 // g /\, r, %SAc •p'�ej, Boring Date:5/14/15 t , e g,'J/ Oe //4G /Qe ' / Boring Location:Tigard,OR ///41/4. 4' `%+oma /O / 0�0,_, tie` � ' f' Drilling Method:Hand Augur S} ML Damp,tan brown,stiff,SILT V.3 c i I '4? 1 vNi 5; k v; ; I r t-3 Y 1 —4 f i-. 29.8 Boring completed at depth of 4ft o w _ Zn... I E - u, 'i-5 I! A a I II , , , V ti 8 I i y i , LOG OF BORING 1 12000 SW ViewCrest Road Rapid Soil Solidi+ns Chris Eschman Plate 1 -. __ i .i._ _ i I , , 1 El A#11. / 7 / i'l / / / / / / / / / / Surface Elevation:433 , . / / (t//'46 /*I°/4164/ / 46 • (.6 / o`)" / A'IP-/ Boring Date:5/14/15 /.4,,* , e /. Boring Location:Tigard,OR / ' P - 1 07,.• 0 / 43/./ 0/ , / 0°,,/,r,,./ Drilling Method:Hand Augur ' — :';':' TP ; Topsoil and silts - , I . , 1 , I. I . , g , 1- 1 i- 5, 2 3, ML Damp,tan brown,fine grained,stiff Portland Hills SILTS cy c g ir g i i N q r 1 a x - 1 i - a 27.4 a - 1 Z 1 5 GWS Damp,medium brown SILTS wth large gravels KC - A i... 1[ t A 1 ii E 0; k A 4 1 --6 14 L GWS Damp,medium brown GRAVELS with some sifts k A ; iii U ft- A .,, .. BA Boring completed at depth of 6.5-BASALT t . , —7 I LOG OF BORING 1 _ 112000 SW ViewCrest Road Rapid Soil Solutions Plate .1 Chris Eschman i