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Report October 12,2016 HGSI Project No. 16-2098 The subject site is underlain by the Quaternary age(last 1.6 million years)Willamette Formation,a catastrophic flood deposit associated with repeated glacial outburst flooding of the Willamette Valley,the last of which occurred about 10,000 years ago(Madin, 1990). Underlying the project site,these deposits consist of horizontally layered,micaceous,silt to fine sand. At least three major fault zones capable of generating damaging earthquakes are known to exist in the region. These include the Portland Hills Fault Zone,Gales Creek-Newberg-Mt.Angel Structural Zone,and the Cascadia Subduction Zone. These potential earthquake source zones are included in the determination of seismic design values for structures, as presented in the Seismic Design section. None of the known faults extend beneath the site. FIELD EXPLORATION EXPLORATORY BORINGS The site-specific exploration for this study consisted of exploratory borings. On September 21,2016,two borings,designated B-1 and B-2,were drilled to depths of approximately 16.5 feet below ground surface (bgs),at an approximate location shown on Figure 2. It should be noted that exploration locations were determined in the field by pacing or taping distances from apparent property corners and other site features shown on the plans provided. As such,the locations of the explorations should be considered approximate. The borehole was drilled using a trailer mounted drill rig and solid stem auger methods. At each boring location, SPT(Standard Penetration Test)sampling was performed in general accordance with ASTM D1586 using a 2-inch outside diameter split-spoon sampler and a 140-pound hammer equipped with a rope and cathead mechanism. During the test,a sample is obtained by driving the sampler 18 inches into the soil with the hammer free-falling 30 inches. The number of blows for each 6 inches of penetration is recorded. The Standard Penetration Resistance("N-value")of the soil is calculated as the number of blows required for the final 12 inches of penetration. If 50 or more blows are recorded within a single 6-inch interval,the test is terminated,and the blow count is recorded as 50 blows for the number of inches driven. This resistance,or N-value,provides a measure of the relative density of granular soils and the relative consistency of cohesive soils. At the completion of the borings,the holes were backfilled with bentonite. Explorations were conducted under the full-time observation of HGSI personnel. Soil samples were classified in the field and representative portions were placed in relatively air-tight plastic bags. These soil samples were then returned to the laboratory for further examination and laboratory testing. Pertinent information including soil sample depths,stratigraphy,soil engineering characteristics,and groundwater occurrence was recorded. Soils were classified in general accordance with the Unified Soil Classification System. Summary boring logs are attached. The stratigraphic contacts shown on the individual logs represent the approximate boundaries between soil types. The actual transitions may be more gradual. The soil and groundwater conditions depicted are only for the specific dates and locations reported,and therefore,are not necessarily representative of other locations and times. SUBSURFACE CONDITIONS The following discussion is a summary of subsurface conditions encountered in our explorations. For more detailed information regarding subsurface conditions at specific exploration locations,refer to the attached boring logs. Also,please note that subsurface conditions can vary between exploration locations,as discussed in the Uncertainty and Limitations section below. 16-2098 13553 Pacific Hwy GR 2 HARDMAN GEOTECHNICAL SERVICES INC. October 12,2016 HGSI Project No. 16-2098 ENGINEERED FILL On-site native soils are considered suitable for use as engineered fill in dry weather conditions,provided they are relatively free of organics and are properly moisture conditioned for compaction. Imported fill material must be approved by the geotechnical engineer prior to being imported to the site. Oversize material greater than 6 inches in size should not be used within 2 feet of foundation footings,and material greater than 12 inches in diameter should not be used in engineered fill. Engineered fill and crushed rock backfill soils should be compacted in horizontal lifts not exceeding 8 inches using standard compaction equipment. We recommend that engineered fill be compacted to at least 90 percent of the maximum dry density determined by ASTM D1557(Modified Proctor)or equivalent. On-site soils may be wet of optimum;therefore,we anticipate that aeration of native soil will be necessary for compaction operations performed during late spring to early summer. Proper test frequency and earthwork documentation usually requires daily observation and testing during stripping,rough grading,and placement of engineered fill. Field density testing should conform to ASTM D2922 and D3017,or D1556. Engineered fill should be periodically observed and tested by the project geotechnical engineer or his representative. Typically,one density test is performed for at least every 2 vertical feet of fill placed or every 250 yd3,whichever requires more testing. WET WEATHER EARTHWORK The on-site soils are moisture sensitive and may be difficult to handle or traverse with construction equipment during periods of wet weather. Earthwork is typically most economical when performed under dry weather conditions. Earthwork performed during the wet-weather season will probably require expensive measures such as cement treatment or imported granular material to compact fill to the recommended engineering specifications. If earthwork is to be performed or fill is to be placed in wet weather or under wet conditions when soil moisture content is difficult to control,HGSI should be contacted for additional recommendations. Under wet weather,the construction area will unavoidably become wet and the condition of exposed fill and native soils will degrade. To limit the impacts of wet weather on the finished building pad surface, consideration may be given to placement of a crushed aggregate pad. Where used,we recommend the working pad be constructed using 11/2"-0 crushed aggregate,and should have minimum thickness of at least 12 inches. This thickness is considered adequate to support light construction traffic,but will not be sufficient to support heavy traffic such as loaded dump trucks or other heavy rubber-tired equipment. SPREAD FOOTING FOUNDATIONS Spread footing foundations are acceptable for use on this project. We recommend a maximum allowable bearing pressure of 2,500 pounds per square foot(psf)for use in design when footings are placed on competent native or properly compacted engineered fill. The recommended maximum allowable bearing pressure may be increased by a factor of 1.33 for short term transient conditions such as wind and seismic loading. Assuming construction is accomplished as recommended herein,and for the foundation loads anticipated,we estimate total settlement of spread foundations of less than about 1 inch and differential settlement between two adjacent load-bearing components supported on competent soil of less than about'A inch. We anticipate that the majority of the estimated settlement will occur during construction,as loads are applied. Wind,earthquakes, and unbalanced earth loads will subject the proposed structure to lateral forces. Lateral forces on a structure will be resisted by a combination of sliding resistance of its base or footing on the underlying soil and passive earth pressure against the buried portions of the structure. For use in design,a 16-2098 13553 Pacific Hwy GR 4 HARDMAN GEOTECHNICAL SERVICES INC. October 12, 2016 HGSI Project No. 16-2098 coefficient of friction of 0.5 may be assumed along the interface between the base of the footing and subgrade soils. Passive earth pressure for buried portions of structures may be calculated using an equivalent fluid weight of 390 pounds per cubic foot(pcf),assuming footings are cast against dense,natural soils or engineered fill. The recommended coefficient of friction and passive earth pressure values do not include a safety factor. The upper 12 inches of soil should be neglected in passive pressure computations unless it is protected by pavement or slabs on grade. Footing excavations should be trimmed neat and the bottom of the excavation should be carefully prepared. Loose,wet or otherwise softened soil should be removed from the footing excavation prior to placing reinforcing steel bars. HGSI should observe foundation excavations prior to placing crushed rock,to verify that adequate bearing soils have been reached. HGSI should monitor crushed rock placement beneath foundations and perform density tests to verify compliance with the engineered fill density specification. CONCRETE SLABS-ON-GRADE Preparation of areas beneath concrete slab-on-grade floors should be performed as recommended in the Site Preparation section. Care should be taken during excavation for foundations and floor slabs,to avoid disturbing subgrade soils. If subgrade soils have been adversely impacted by wet weather or otherwise disturbed,the surficial soils should be scarified to a minimum depth of 8 inches,moisture conditioned to within about 3 percent of optimum moisture content,and compacted to engineered fill specifications. Alternatively,disturbed soils may be removed and the removal zone backfilled with additional crushed rock. For evaluation of the concrete slab-on-grade floors using the beam on elastic foundation method,a modulus of subgrade reaction of 200 kcf(115 pci)should be assumed for the soils anticipated at subgrade depth. This value assumes the concrete slab system is designed and constructed as recommended herein,with a minimum thickness of crushed rock of 8 inches beneath the slab. Interior slab-on-grade floors should be provided with an adequate moisture break. The capillary break material should consist of ODOT open graded aggregate per ODOT Standard Specifications 02630-2. The minimum recommended thickness of capillary break materials on re-compacted soil subgrade is 8 inches. The total thickness of crushed aggregate will be dependent on the subgrade conditions at the time of construction,and should be verified visually by proof-rolling. Under-slab aggregate should be compacted to at least 90%of its maximum dry density as determined by ASTM D1557 or equivalent. In areas where moisture will be detrimental to floor coverings or equipment inside the proposed structure, appropriate vapor barrier and damp-proofing measures should be implemented. A commonly applied vapor barrier system consists of a 10-mil polyethylene vapor barrier placed directly over the capillary break material. With this type of system,an approximately 2-inch thick layer of sand is often placed over the vapor barrier to protect it from damage,to aid in curing of the concrete,and also to help prevent cement from bleeding down into the underlying capillary break materials. Other damp/vapor barrier systems may also be feasible. Appropriate design professionals should be consulted regarding vapor barrier and damp proofing systems,ventilation,building material selection and mold prevention issues,which are outside HGSI's area of expertise. PERIMETER FOOTING DRAINS To minimize soil moisture fluctuations adjacent to the building,we recommend the outside edge of perimeter footings be provided with a drainage system consisting of 3-inch minimum diameter perforated plastic pipe embedded in a minimum of 1 ft3 per lineal foot of clean, crushed drain rock. The drain pipe and surrounding drain rock should be wrapped in non-woven geotextile(Mirafi 140N,or approved equivalent)to minimize the potential for clogging and/or ground loss due to piping. Water collected from the footing drains should be directed into the local storm drain system or other suitable outlet. A minimum 0.5 percent fall should be 16-2098 13553 Pacific Hwy GR 5 HARDMAN GEOTECHNICAL SERVICES INC. October 12,2016 HGSI Project No. 16-2098 maintained throughout the drain and non-perforated pipe outlet. The footing drains should include clean-outs to allow periodic maintenance and inspection. Down spouts and roof drains should collect roof water in a system separate from the footing drains in order to reduce the potential for clogging. Roof drain water should be directed to an appropriate discharge point well away from structural foundations. Grades should be sloped downward and away from buildings to reduce the potential for ponded water near structures. PERMANENT BELOW-GRADE WALLS Lateral earth pressures against below-grade retaining walls will depend upon the inclination of any adjacent slopes,type of backfill,degree of wall restraint,method of backfill placement,degree of backfill compaction, drainage provisions,and magnitude and location of any adjacent surcharge loads. At-rest soil pressure is exerted on a retaining wall when it is restrained against rotation. In contrast,active soil pressure will be exerted on a wall if its top is allowed to rotate or yield a distance of roughly 0.001 times its height or greater. If the subject retaining walls will be free to rotate at the top,they should be designed for an active earth pressure equivalent to that generated by a fluid weighing 35 pcf for level backfill against the wall. For restrained wall,an at-reset equivalent fluid pressure of 55 pcf should be used in design,again assuming level backfill against the wall. These values assume that the recommended drainage provisions are incorporated, and hydrostatic pressures are not allowed to develop against the wall. During a seismic event, lateral earth pressures acting on below-grade structural walls will increase by an incremental amount that corresponds to the earthquake loading. Based on the Mononobe-Okabe equation and peak horizontal accelerations appropriate for the site location, seismic loading should be modeled using the active or at-rest earth pressures recommended above,plus an incremental rectangular-shaped seismic load of magnitude 5.5H,where H is the total height of the wall. We assume relatively level ground surface below the base of the walls. As such,we recommend passive earth pressure of 390 pcf for use in design,assuming wall footings are cast against competent native soils or engineered fill. If the ground surface slopes down and away from the base of any of the walls,a lower passive earth pressure should be used and HGSI should be contacted for additional recommendations. A coefficient of friction of 0.5 may be assumed along the interface between the base of the wall footing and subgrade soils. The recommended coefficient of friction and passive earth pressure values do not include a safety factor,and an appropriate safety factor should be included in design. The upper 12 inches of soil should be neglected in passive pressure computations unless it is protected by pavement or slabs on grade. The above recommendations for lateral earth pressures assume that the backfill behind the subsurface walls will consist of properly compacted structural fill,and no adjacent surcharge loading. If the walls will be subjected to the influence of surcharge loading within a horizontal distance equal to or less than the height of the wall,the walls should be designed for the additional horizontal pressure. For uniform surcharge pressures,a uniformly distributed lateral pressure of 0.3 times the surcharge pressure should be added. Traffic surcharges may be estimated using an additional vertical load of 250 psf(2 feet of additional fill),in accordance with local practice. The recommended equivalent fluid densities assume a free-draining condition behind the walls so that hydrostatic pressures do not build-up. This can be accomplished by placing a minimum 12-inch wide zone of sand and gravel containing less than 5 percent fines against the walls. A 3-inch minimum diameter perforated,plastic drain pipe should be installed at the base of the walls and connected to a suitable discharge point to remove water in this zone of sand and gravel. The drain pipe should be wrapped in filter fabric (Mirafi 140N or other as approved by the geotechnical engineer)to minimize clogging. 16-2098 13553 Pacific Hwy GR 6 HARDMAN GEOTECHNICAL SERVICES INC. October 12,2016 HGSI Project No. 16-2098 HGSI should be contacted during construction to verify subgrade strength in wall keyway excavations,to verify that backslope soils are in accordance with our assumptions,and to take density tests on the wall backfill materials. SEISMIC DESIGN Structures should be designed to resist earthquake loading in accordance with the methodology described in the 2012 International Building Code(IBC)with applicable 2014 Oregon Structural Specialty Code(OSSC) revisions. We recommend Site Class D be used for design per the OSSC,which references ASCE 7-10, Chapter 20,Table 20.3-1. Design values determined for the site using the USGS(United States Geological Survey)Earthquake Ground Motion Parameters utility are summarized on Table 1. Table 1. Recommended Earthquake Ground Motion Parameters(2012 IBC/2014 OSSC) Parameter Value Location(Lat,Long),degrees 45.4218,-122.7843 Mapped Spectral Acceleration Values (MCE, Site Class B): Short Period, SS 0.964 g 1.0 Sec Period,S1 0.421 g Soil Factors for Site Class D: Fa 1.114 F„ 1.579 SDS=2/3 x Fa x Ss 0.716 g SDI =2/3 x F,,xSI 0.443 g EXCAVATING CONDITIONS AND UTILITY TRENCH BACKFILL We anticipate that on-site soils can be excavated to depths of at least 13 feet using conventional heavy equipment such as trackhoes. Weathered basalt bedrock was not encountered in any of the borings, excavated to a maximum depth of 13 feet bgs. Please note that if excavations extend deeper than about 13 feet bgs, caving soil conditions and perched groundwater should be anticipated. Additional geotechnical evaluations should be performed to develop specific shoring and dewatering measures for any excavations deeper than about 13 feet bgs. Maintenance of safe working conditions,including temporary excavation stability,is the responsibility of the contractor. Actual slope inclinations at the time of construction should be determined based on safety requirements and actual soil and groundwater conditions. All temporary cuts in excess of 4 feet in height should be sloped in accordance with U.S.Occupational Safety and Health Administration(OSHA) • regulations(29 CFR Part 1926),or be shored. The existing native soils classify as Type B Soil and temporary excavation side slope inclinations as steep as IFI:l V may be assumed for planning purposes. This cut slope inclination is applicable to excavations above the water table only. Flatter temporary excavation • slopes will be needed if groundwater is present,or if significant thicknesses of sandy soils are present in excavation sidewalls. Perched groundwater conditions often occur over fine-grained native deposits such as those beneath the site, particularly during the wet season. If encountered,the contractor should be prepared to implement an appropriate dewatering system for installation of the utilities. At this time,we anticipate that dewatering systems consisting of ditches,sumps and pumps would be adequate for control of groundwater where 16-2098 13553 Pacific Hwy GR 7 HARDMAN GEOTECHNICAL SERVICES INC. October 12,2016 HGSI Project No. 16-2098 encountered during construction conducted during the dry season. Regardless of the dewatering system used,it should be installed and operated such that in-place soils are prevented from being removed along with the groundwater. Vibrations created by traffic and construction equipment may cause some caving and raveling of excavation walls. In such an event,lateral support for the excavation walls should be provided by the contractor to prevent loss of ground support and possible distress to existing or previously constructed structural improvements. Utility trench backfill should consist of%"-0 crushed rock,compacted to at least 90%of the maximum dry density obtained by Modified Proctor(ASTM D1557)or equivalent. Initial backfill lift thick nesses for a %"-0 crushed aggregate base may need to be as great as 4 feet to reduce the risk of flattening underlying flexible pipe. Subsequent lift thickness should not exceed 1 foot. If imported granular fill material is used, then the lifts for large vibrating plate-compaction equipment(e.g.hoe compactor attachments)may be up to 2 feet,provided that proper compaction is being achieved and each lift is tested. Use of large vibrating compaction equipment should be carefully monitored near existing structures and improvements due to the potential for vibration-induced damage. Adequate density testing should be performed during construction to verify that the recommended relative compaction is achieved. Typically,one density test is taken for every 4 vertical feet of backfill on each 200- lineal-foot section of trench. EROSION CONTROL CONSIDERATIONS During our field exploration program,we did not observe soil types that would be considered highly susceptible to erosion. Erosion at the site during construction can be minimized by implementing the project erosion control plan,which should include judicious use of straw,bio-bags,silt fences,or other appropriate technology. Where used,erosion control devices should be in place and remain in place throughout site preparation and construction. Areas of exposed soil requiring immediate and/or temporary protection against exposure should be covered with either mulch or erosion control netting/blankets. UNCERTAINTIES AND LIMITATIONS We have prepared this report for the owner and his/her consultants for use in design of this project only. This report should be provided in its entirety to prospective contractors for bidding and estimating purposes; however,the conclusions and interpretations presented in this report should not be construed as a warranty of the subsurface conditions. Experience has shown that soil and groundwater conditions can vary significantly over small distances. Inconsistent conditions can occur between explorations that may not be detected by a geotechnical study. If,during future site operations, subsurface conditions are encountered which vary appreciably from those described herein,HGSI should be notified for review of the recommendations of this report,and revision of such if necessary. Sufficient geotechnical monitoring,testing and consultation should be provided during construction to confirm that the conditions encountered are consistent with those indicated by explorations. Recommendations for design changes will be provided should conditions revealed during construction differ from those anticipated,and to verify that the geotechnical aspects of construction comply with the contract plans and specifications. Within the limitations of scope, schedule and budget,HGSI executed these services in accordance with generally accepted professional principles and practices in the field of geotechnical engineering at the time the report was prepared. No warranty,expressed or implied,is made. The scope of our work did not include 16-2098 13553 Pacific Hwy GR 8 HARDMAN GEOTECHNICAL SERVICES INC. October 12,2016 HGSI Project No. 16-2098 environmental assessments or evaluations regarding the presence or absence of wetlands or hazardous or toxic substances in the soil,surface water,or groundwater at this site. 0.0 We appreciate this opportunity to be of service. Sincerely, HARDMAN GEOTECHNICAL SERVICES INC. ��EO PRUi <0 ..NGIN ' LA 64,t'll) • T .46 t OREGON 06.42110 f8ER 26 'r L. HO) EXPIRES: 06-30-201 Scott L. Hardman,P.E., G.E. Geotechnical Engineer Attachments: References Figure 1 —Vicinity Map Figure 2—Site Plan Logs of Borings B-1 and B-2 ®tty.®.gb-0,-Gt6.®tb-®rbo®t44-®ib.®r�®ra.®rt.®tb-®rb-®e4-®sb-®ib.Gib•eatr®&-®itAetto®rb•® REFERENCES Beeson, M.H.,Tolan,T.L.,and Madin,I.P., 1991,Geologic map of the Portland Quadrangle, Multnomah,and Washington Counties,Oregon:Oregon Department of Geology and Mineral Industries Geological Map Series GMS-75,scale 1:24,000. Madin, I.P., 1990,Earthquake hazard geology maps of the Portland metropolitan area, Oregon: Oregon Department of Geology and Mineral Industries Open-File Report 0-90-2, scale 1:24,000,22 p. Snyder,D.T.,2008,Estimated Depth to Ground Water and Configuration of the Water Table in the Portland, Oregon Area: U.S.Geological Survey Scientific Investigations Report 2008-5059,41 p.,3 plates. 16-2098 13553 Pacific Hwy GR 9 HARDMAN GEOTECHNICAL SERVICES INC. HamHARDMAN GEOTECHNICAL VICINITY MAP SERVICES INC. Practical,Cost-Effective Geotechnical Solutions • •yis �Dl,1-'; \1 ��� y r - --a Ia E est Institut Tigard ''. '" s MIR 0� 1 0° \� — h r;,1,v SW SOAK ST init r ,v„ , 000 SH'IRONWOOD" " �-r- NM4.� / N I1 7_ Y" CT _` 7. -----,, a SW SPRI±•�' ' ! SW SPRUCE ST ,M1% i- ' -'•� o) ,-.t- ' arm' ��",� r'' ' i E ' OW_CREEK I - �1 r w '� Ism II — lc uotr 1 SW N DAKOTA sr r ys;" 413IC Pig Zi - \ i , a r _.a ''+ atSW PFAFFtE Sr I 4 8 0� M yf . 1 ry # GRD 3 \� �� Tigard \\ im s i�1(1�V1�_ ..amu al If ■� \ & Park and , SUMMER ORES o" il '0 /��. Ride,.' _ 1, mi t '� * ..�''^+�. Nr,. -r-`•�� V' .411"1141%1111 11 lOkS loner v►� c �� i \ Cr tQl H sr t 4' it, I ' -' `'-- , ' \--, 7-----,s4'''' 1? --`44,5' .--'4'-'1111kr tel' L.ke c) 44.;-/ (,t... Mj �4 '\'---) ,-,------ 1 4,01s ii)wb, I Q 1 i -- i, ilk / 46-..........40, ♦ `, Tra '�-�Ydoark� 7 i if a„din 2„, _ �1 �► f ' - a •'Ride\\\ Q i Pi ter rieri."..z‘N., - ..40 .,' .,'":( ' ' Oa IP' a im %A , �)�1r"`. Q � 61 ►AN, r i I6111,7:4. ..mikwil ( JIB"• ir ajlip,s ` ilipsigok hil 1 4 .t T( iiii." � SW EDGEWOOD \'�..Lt ~ 1�S,,,"" ' l07- ' 411. r /firy� ''� ,C ,l14. moi'-I 1 � Jam. ' Dn .��' ,fij-,/ n '\ IM 1 _ �� �"" i" .��\\1r "ii _ •0. (� OCR D� t3`1t'400�SW`MCFApI \' --Tigard,w Q`f')`• 9116` Bi Il1LA p _ J/► l-vangelical Cem M�o,' .. , ,,, ' `„\ �' ♦ m Q� �\ 3��l ` __SW DONITAyRD l - -, Approximate Site Location jiaf 1 •f1 ���1 ,in-4-7,1,42„i" in§ thre[a ,` /infix i !moi,PINEBPM Ai, j VI urchi rk,as.:"rid Fide a r r,� '% rail All ( I i }} ' diczt:*.11 11 p 111 ! J fsw, r , SW-Li1DY MA. w "."/`. �3 �' yDR a SW-SATTLER STII I-Ei �n1 ,n- S�ASNFOROST A.* D.0 wo IiL4k . ' 1r SW_•SUMMERF.IECD m `^ lib.. SWDURHAM;RD d 1 SW WRHAMaq %....,t.Es/Avt i!Ai j Illy q ali 11111000"vr \``'''`');,1:3 : .4 :::oroirr— I. w '\,\ ji CaswillE ,L:s 'eilfhi/06/0 •§P I c)L. f'? 0 -r-- Project: 13553 SW Pacific Highway Project No. 16-2098 FIGURE 1 Tigard, Oregon HARDMAN GEOTECHNICAL SITE AND SERVICES INC. EXPLORATION PLAN Practical,Cost-Effective Geotechnical Solutions 354 ; 0 I �V itiitAi ,, , kl,,,,A,,,3 'N 4 AL 4 , / , I ' ** '' S 1 3599_ 4,4%,0 / /4' mak' ; ,,14.,-.:ixi 4, , �a rt , , • ' a3 - #' AP Legend Base map provided by B-i Portland Maps Boring Designation Ilillov and Approximate Location Project: 13553 SW Pacific Highway Project No. 16-2098 FIGURE 2 Tigard, Oregon • BORING LOG Project: 13553 SW Pacific Highway Tigard, Oregon Project No. 16-2098 Boring No. B-1 N O `- co . n \O w. n C 3 o g Material Description (1) � o — �`" 25 o 0_co o 0 U 4 inches of Top Soil Stiff, Silt with coarse sand, brown, dry (fill) X14 5 JX 10 Stiff, Clayey silt with sand, brown with orange and gray mottling, slightly moist to moist(native) 13 10—X 9 Medium stiff to stiff, Clayey sand, brown with orange, very moist Loose, Sand with clay, brown, wet 15 >< 3 Sample disturbed; SPT N-value at 15 feet not reliable Boring terminated at 16.5 feet Groundwater encountered at 13 feet 20 25 Neel HARDMAN LEGEND GEOTECHNICAL SERVICES INC. Date Drilled: 9-21-16 Prac:rcai,wst-Errective Geotechnical Solutims 10110 SW Nimbus Avenue,Suite B-5 Logged By: IDM Portland,Oregon 97223 STP Drive Sample Water Level at (503)530-8076 Time of Drilling • • BORING LOG Project: 13553 SW Pacific Highway Tigard, Oregon Project No. 16-2098 Boring No. B-2 N T o fn" N( 0 .N Cc Material Description0 c o — — C0-00 U 0 4 inches of T2p Soil Stiff, Silt with coarse sand, brown, dry(fill) -f// �` 11 5 �� 16 Stiff, Clayey silt with sand, brown with orange and gray mottling, slightly moist to < 10 moist (native) 10/x 4 Medium stiff to soft, Clayey sand, brown with orange, very moist Loose, Sand with clay, brown, wet 15 4 Sample disturbed; SPT N-value at 15 feet not reliable Boring terminated at 16.5 feet Groundwater encountered at 13 feet 20- 25— HARDMAN LEGEND 11831 GEOTECHNICAL SERVICES INC. Date Drilled: 9-21-16 Practical,CmFETkcir a Geotechncal Solutions 10110 SW Nimbus Avenue,Suite B-5 Logged By: IDM Portland,Oregon 97223 STP Drive Sample Water Level at (503)530-8076 Time of Drilling