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HomeMy WebLinkAboutSWP273531 (14)REPORT OF GEOTECHNICAL STUDY LAKE WASHINTON BOULEVARD STORM AND WATER IMPROVEMENTS RENTON, WASHINGTON S&EE JOB NO. 1002 MARCH 17, 2010 C'tY of Penton Planning Division JUN 2 4 2010 fc-3) E c Efl'WED 002rpt S&EE S&EE SOIL & ENVIRONMENTAL ENGINEERS, INC. 16625 Redmond Way Suite M 124, Redmond. Washington 98052 (425) 868-5868 March 17, 2010 Mr. Barry Baker, PE Gray & Osborne, Inc. 701 Dexter Ave. N., Suite 200 Seattle, WA 98109 Report Geotechnical Investigation Lake WA Blvd Storm and Water Improvements Renton, WA Dear Barry: We are pleased to present herewith our Report of Geotechnical study for the referenced project. Our services were authorized by Gray and Osborne, Inc. and have been provided in accordance with our proposal dated December 7, 2009. We appreciate the opportunity to provide our services. Should you have any questions regarding the contents of this report or require additional information, please contact the undersigned. 28166' 4 �SIQMAL EZ1G EWIRES 1002rpt Very truly yours, SOIL & ENVIRONMENTAL ENGINEERS, INC. C. J. Shin, Ph.D., P.E. President /o S&EE TABLE OF CONTENTS Section Page 1.0 INTRODUCTION............................................................................................................................................... 1 2.0 SCOPE OF WORK............................................................................................................................................. 1 3.0 SITE CONDITIONS............................................................................................................................................ 2 3.1 SURFACE CONDITIONS................................................................................................................................2 3.2 GEOLOGY........................................................................................................................................................ 3 3.3 SUBSURFACE CONDITIONS........................................................................................................................ 3 3.4 GROUNDWATER CONDITIONS.................................................................................................................. 4 4.0 LABORATORY TESTING................................................................................................................................. 5 5.0 CONCLUSIONS AND RECOMMENDATIONS.............................................................................................. 5 5.1 STORM LINE CONSTRUCITON..................................................................................................................... 5 5.2 WATERLINE INSTALLATION...................................................................................................................... 7 5.3 TEMPORARY AND PERMANENT SLOPES................................................................................................. 7 5.4 SEISMIC CONSIDERATIONS AND HAZARDS............................................................................................ 8 5.5 CONSTRUCTION DEWATERING................................................................................................................. 8 5.6 ADDITIONAL SERVICES............................................................................................................................... 9 6.0 CLOSURE............................................................................................................................................................. 9 FIGURE 1: SITE LOCATION MAP FIGURE 2: SITE AND EXPLORATION PLAN APPENDIX A: FIELD EXPLORATION AND LOGS OF BORINGS APPENDIX B: LABORATORY TEST RESULTS 1002rpt i S&EE ' REPORT OF GEOTECHNICAL STUDY LAKE WASHINGTON BOULEVARD STORM & WATER IPROVEMENTS ' RENTON, WASHINGTON For GRAY & OSBORNE, INC. 1.0 INTRODUCTION ' This report summarizes the results of our geotechnical study for the proposed Lake Washington Boulevard Storm and Water Improvement project. A Site Location Map is shown in Figure 1 and a Site and Exploration Plan is shown in Figure 2, both are included at the end of this report. We understand that the project involves the installation of a storm water trunk line and a water line. The storm line will be ' about 900 feet in length and along the east side of the road. The majority of the line will be located in the existing drainage ditch which will be filled to the street level. As such, about 5 to 6 feet of maximum fill ' will be required. The new water line will be located in the road shoulder just to the west of the drainage ditch. Two thrust blocks will be required near the south end of the new water line where the line will turn ' west across the road. 2.0 SCOPE OF WORK ' The purpose of our study is to provide recommendations regarding the geotechnical component of the project. Specifically, our services included the followings: ' 1. Review of existing regional and local geologic information, reports, and studies relevant to the project design. ' 2. Performance of onsite subsurface investigations by the drilling of two soil test borings and mo hand ' auger borings. 3. Performance of a laboratory testing program. 4. Performance of engineering analyses to evaluate the settlement potential of compressible subsoils; ' assessment of impacts and recommendations regarding mitigation. IIo02rpt [*fllgD1 N 6. Recommendations regarding types of suitable imported fill, fill placement techniques, and compaction criteria. ' 7. Recommendations regarding passive earth pressures and coefficient of friction for the thrust block design. 8. Consideration of seismic conditions and potential impacts. ' 9. Preparation of this written report documenting our findings and recommendations. 3.0 SITE CONDITIONS 3.1 SURFACE CONDITIONS ' For most of the project area, a storm water drainage ditch currently flanks the eastside of Lake Washington Boulevard. The bottom of the ditch was about 4 to 6 feet below the street level. The slopes at the west side of the ditch were covered with crushed rock and incline at about 1.5H:IV. Flatter side ' slopes, ranging from about 2H:1 V in the southern portion to 5H:1 V in the northern portion are present along the east side of the ditch. At the time of our field exploration, the ditch bottom is covered with tall grass and about 6 to 12 inches of water was present in the ditch. The ditch connects to a culvert near the south end of the project area. The ditch bottom is about 5 feet in width, except in the northern portion of the ditch where the east side slope has been flattened, the ditch bottom becomes over 15 feet in width. An existing, single -story, metal building is present along the east side of the ditch. The distance from the center of the drainage ditch to the building varies from about 10 to 25 feet at the south and north ends of the building, respectively. ' Underground utilities along the east side of the road include power and communication. Underground utilities along the west side of the road include water, gas and an 84-inch diameter, pile -supported ' sanitary sewer pipe. The railroad (BNSF) embankment is present to the west of this pipe. 1 1002rpc 2 S&EE ' 3.2 GEOLOGY General The project site lies in the middle portion of the Puget Lowland, an elongated topographic and structural depression filled with a complex sequence of glacial and non -glacial sediments that overlie Tertiary bedrock. The soils deposited during and after the most recent glaciation dominate the surface and ' subsurface geologic conditions in the project area. These soils are highly interwoven by repeated sequences of deposition and mass wasting such as erosion and land -sliding. Published geologic ' information (Generalized Geologic Map of Northwestern King County, Washington State Department of Natural Resources) indicates that the site area is underlain by undifferentiated sedimentary deposits (Qa). The materials include inter -fingered clay, silt, peat, sand and gravel. Previous field explorations in the ' project area indicate that the depth to bedrock is about 45 feet. (Seahawks Headquarters and Practice Facility, Renton, WA by Shannon & Wilson, Inc., November 14, 2006). Seattle Fault ' The Seattle Fault is a collective term for a series of four or more east -west -trending, south -dipping south -di ifault ' strands underlying the Seattle area. The southernmost mapped strand of the Seattle Fault is the closest known fault to the site. This thrust fault zone is approximately 2 to 4 miles wide (north -south) and extends from the Kitsap Peninsula near Bremerton on the west to the Sammamish Plateau east of Lake Sammamish on the east. The four fault strands have been interpolated from over -water geophysical surveys (Johnson, et al.,, 1999) and, consequently, the exact locations on land have yet to be determined or verified. Recent geologic evidence suggests that movement on this fault zone occurred about 1,100 years ago, and the earthquake it produced was on the order of a magnitude 7.5. 3.3 SUBSURFACE CONDITIONS We explored the subsurface soil conditions along the storm line alignment by the drilling of two soil test ' borings, B-1 and B-2, and t-wo hand auger borings HA-1 and HA-2. Borings B-1 and B-2 was drilled outside and near the south and north ends of the drainage ditch, respectively. Borings HA-1 and HA-2 were drilled inside the ditch. The locations of these borings are shown on Figure 2 which is included at the end of this report. Details of the field exploration and logs of borings are included in Appendix A. In general, our borings show relatively consistent conditions, and the soils encountered are similar to 1002rpt 3 S&EE materials described in the published geologic map. From the top do�Nn, the subsurface conditions include the following strata: ' I) Fill Borings B-1 and B-2 encountered about 4 to 6 feet of fill; Boring HA -I encountered about 4 feet of fill; and HA-2 did not encounter any fill. The fill consisted of silty sand with gravel. The soil is generally damp and loose. ' II) Recent sedimentary deposits ' This layer is about 20 feet in thickness and consists of very loose to loose sand with lenses or layers of very soft silt. Trace of organics including decomposed wood was found in the ' deposits. III) Glacial soils ' This layer consists of medium dense to very dense sand with gravel. The top of this layer was found at about 30 and 28.5 feet below the ground surface at 13-1 and B-2, respectively. 3.4 GROUNDWATER CONDITIONS As previously mentioned, about 6 to 12 inches of water was present in the drainage ditch at the time of ' our field exploration on December 28, 2009. Borings B-1 and B-2 found groundwater at about the same depth during drilling. Based on a previous study "Groundwater Discipline, I-405INE 44'" Street Intersection, Renton, WA by Shannon & Wilson". The shallowest groundwater table in the project vicinity has an average depth of 15 feet below ground surface. We anticipate that the depth of this shallow groundwater will vary with season and precipitation. 00'r" 4 S&EE ' 4.0 LABORATORY TESTING ' One undisturbed, Shelby -tube sample was retrieved from the compressible silt layer at HA-2. The sample was transported to our sub -contracted soil laboratory for a consolidation test. The test results are included in Appendix B. The test results show that the silt has a moderate compression index of 7 percent (a parameter measuring ' the compressibility); and a moderate coefficient of consolidation of 2 ft2/day (a parameter measuring the speed of consolidation). 1 5.0 CONCLUSIONS AND RECOMMENDATIONS 5.1 STORM LINE CONSTRUCITON Settlement The subsurface soils at the existing drainage ditch have a moderate compressibility. Based on our evaluation, the new fill to be placed in the existing ditch will incur about 2 to 3 inches of ground settlement near the center line of the ditch. The time to reach the consolidation maturity will be about one to two months. Due to the variation of subsoils, the ground settlement would not be uniform along the ditch line. We estimate that a differential settlement of one to 2 inches may occur for every 50 lineal feet of the storm line. A higher differential settlement, on the order of 2 to 3 inches may occur at the north and south ends of the ditch line where the depth of fill will transition abruptly from minimal to about 5 feet. The differential settlement may cause pipe joins to distress and thus should be considered in material selections. Mitigation to such potential problem may include the use of flexible pipes and joints. The overburden from the ditch fill will also cause slight settlement on both sides of the ditch. Our evaluations show that about 1/2 inches of ground settlement may occur along the road shoulder. We believe that there will be a slight chance of ground fissures or cracks in the shoulder; however the chance of pavement damage is remote. An existing metal building is present to the east of the ditch line. To avoid adverse impacts by the new fill, we recommend that the edge/toe of the new fill be at least 10 feet from the building. If fill has to be l oo2rpt 5 S&EE placed closer than 10 feet, the support condition of the building foundation should be explored. The exploration may include potholing next to the building. An evaluation should also be performed to assess the settlement potential that may be induced by the new fill and mitigation options. Conventional ' solution in such scenario typically involve under -pinning the building foundations with small diameter pipe piles (pin piles). Subgrade Preparation in Existing Ditch ' Very soft silt and loose sand are present at the bottom of the existing ditch. Prior to the placement of the ' pipe bedding material, the subgrade should be prepared and stabilized. We recommend that all vegetation in the fill area be removed, and the subgrade be over -excavated 12 inches. A non -woven geotextile having a minimum grab tensile strength of 200 pounds should be placed at the over -excavated ' subgrade. The over -excavation should then be backfilled with 2-inch minus crushed rock. The rock should be placed in one lift and compacted by at least 3 passes of a mechanical compactor that weighs a minimum of 300 pounds. Pie Bedding We recommend that the pipe be bedded with at least 4 inches bedding material that meets WSDOT ' aggregate specification 9-03.12(3). I Ditch Fill ' Structural fill should be used and the materials should meet both the material and compaction requirements presented below. Material Requirements: Structural fill should be free of organic and frozen materials and can include silty sand, sand, mixture of sand and gravel (pitrun), gravel, or quarry -processed stone. Structural fill material should be approved by the project geotechnical engineer prior to use. ' Placement and Compaction Requirements: Structural fill should be placed in loose horizontal lifts not exceeding a thickness of 6 to 12 inches, depending on the material type, compaction equipment, ' and number of passes made by the equipment. Each lift should be compacted to at least 95% of the maximum dry density as determined using the ASTM D-1557 test procedures. ioo2rpt 6 S&EE Catch Basin Subgrade Wet and soft soils may be encountered at the subgrade. In this event, the subgrade should be stabilized to ' avoid excessive structure settlement. Subgrade stabilization can include over -excavation of 12 inches and backfill with compacted crushed rock. Groundwater may be encountered; we anticipate that the seepage ' rate will be low and the water can be handled by pumping from sumps. 5.2 WATER LINE INSTALLATION ITrench Excavation and Backfill ' The excavation for the water line should encounter silty sand with gravel. The trench wall should be stable without shoring if less than 3 feet in depth. We anticipate a stable trench subgrade. As such, pipe ' bedding material can be placed over subgrade once the loose cuttings are removed. We anticipate that the excavated soil can be used for trench backfill. Please note that this soil is silty in nature and thus will ' be moisture sensitive. Imported structural fill should be used if moisture -conditioning of the onsite soil is not practical. The criteria for the structural fill are stated above. IThrust Block Design ' Concrete thrust blocks can be designed with a passive soil resistance of 200 pounds per cubic feet, equivalent fluid density and a coefficient of friction 0.5 at the base. These values include a safety factor of ' 1.5. Soft silt may be present at the thrust block subgrade. This soil is susceptible to strength loss due to disturbance. If occurs, the subgrade should be stabilized to avoid excessive block settlement. Subgrade stabilization can include over -excavation of 12 inches and backfill with compacted crushed rock. 5.3 TEMPORARY AND PERMANENT SLOPES ' When temporary excavations are required during construction, the contractor should be responsible for the safety of their personnel and equipment. The followings cut angles are provided only as a general ' reference: l oo2rpt 7 S& EE For temporary excavations less than 3 feet in depth, the cut bank may be excavated vertically. For temporary excavations greater than 3 feet but less than 5 feet in depth, the cut should be sloped no steeper than 1 H:1 V from top to bottom. Flatter slopes for all temporary cuts may be required if seepage occurs. All permanent slopes should be no steeper than 2H:IV. Water should not be allowed to flow uncontrolled over the top of any slope. Also, all permanent slopes should be seeded with the appropriate species of vegetation to reduce erosion and maintain the slope stability. 5.4 SEISMIC CONSIDERATIONS AND HAZARDS The project site is situated within Seismic Zone 3. We recommend that Site Class D as defined in the 2006 ' IBC be considered for any seismic design. Due to the presence of loose sandy subsoils and shallow groundwater table, the site is susceptible to liquefaction hazards. ' Liquefaction is a condition when vibration or shaking of the around results in the excess ore pressures q g b P ' in saturated soils and subsequent loss of strength. Liquefaction can result in ground settlement or heaving. In general, soils which are susceptible to liquefaction include saturated, loose to medium dense sands. However, recent studies show that liquefaction can also occur in fine-grained (silty and clayey) soils during strong earthquakes. (Bray, J.D., et. al. 2004). It is our opinion that the soft subsoils at the site have a moderate to high liquefaction potential. Therefore, moderate to severe distortion to the storm line may occur. It is our opinion that post -earthquake maintenance will be a reasonable mitigation option. 5.5 CONSTRUCTION DEWATERING Depending on the season of the proposed construction, the subgrade of the proposed storm line may be dry ' or 6 to 12 inches below the groundwater table. We envision that if the construction occurs in the winter months, the storm water that is currently running in the ditch should be collected at an upstream location ' and discharge at a downstream location using a temporary pipe line. A temporary concrete dam may be needed at the collection point. Assuming an over -excavation depth of 12 inches below the subgrade, our ' flow net analyses show that a groundwater inflow of about 0.2 to 0.5 gallons per hour per lineal foot of the ditch may occur. We believe that this groundwater flow can be handled by sump pumps spaced at 50 to 100 ' feet along the ditch. The discharged water from the sumps will be turbid and will required sediment control before discharge. 1102rpc 8 S&EE 5.6 ADDITIONAL SERVICES Additional services may be required during the design and construction of the project. We envision that the services may include the following: 1. Review of design plans to confirm that our geotechnical recommendations are properly implemented in the design. 2. Attendance of design meetings and provision of design support. 3. Construction monitoring services. The tasks of our monitoring service will include the followings: 3.1 Review contractor's submittals. 3.2 Observe and approve structural fill material. 3.3 Monitor excavation and subgrade stabilization. 3.4 Monitoring of placement and compaction of structural fill. 4. Other geotechnical issues deemed necessary. 6.0 CLOSURE The recommendations presented in this report are provided for design purposes and are based on soil conditions disclosed by field observations and subsurface explorations. Subsurface information presented herein does not constitute a direct or implied warranty that the soil conditions between exploration locations can be directly interpolated or extrapolated or that subsurface conditions and soil variations different from those disclosed by the explorations will not be revealed. The recommendations outlined in this report are based on the assumption that the development plan is consistent with the description provided in this report. If the development plan is changed or subsurface conditions different from those disclosed by the exploration are observed during construction, we should be advised at once so that we can review these conditions, and if necessary, reconsider our design recommendations. 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HA-1 Approximate Hand Auger Boring Location Site And Exploration Plan 1 APPENDIX A FIELD EXPLORATION AND LOGS OF BORINGS ' The soil strata at the project site were investigated by the drilling of two soil test borings, B-1 and B-2 and two hand auger borings, HA-1 and HA-2 on December 28, 2009. The soil test borings were ' advanced by 3-inch I.D. hollow stem auger using a track -mounted drill rig. A representative from S&EE was present throughout the drilling to observe the operations, log subsurface soil conditions, obtain soil ' samples, and to prepare descriptive geologic logs of the exploration. Soil samples were taken at 2.5- and 5-foot interval in general accordance with ASTM D-1586, "Standard Method for Penetration Test and Split -Barrel Sampling of Soils". After the boring was terminated, the borehole was backfilled with bentonite chips. The hand auger borings were drilled with 3-inch O.D. hand auger by a field representative from our office. The hand auger boreholes were backfill with onsite soil after the drilling ' was terminated. The boring logs are included in this appendix. A chart showing the Unified Soil Classification Syste►n is included at the end of this appendix. 1002rut S&EE p —0 a a� op _; c/ J BORING B-1 Soil Description 1 18 sM Brown and dark brown silty fine sand with some crushed rock (damp)(very loose)(fill) I 1 � I 1 18 2 5 1 I I ' 2 1 I I ML Dark gray silt with fine sand lenses, some organics (wood debris)(damp)(very soft) —5 0 18 0 18 I I I 0 I I I I I 1 I ' I ' I ' i 1 18 ' 8 18 I I ' ' sP Gray fine sand with silt lenses (wet)(loose) I —10 I 4 i 18 I I I 4 18 4 I 1 I I I ' I ' I I I I I I —151 I I I 1 I ' 1 I I I 1 1 11s' 3 18 I I 4 I ' I ' I 1 ' I I I - decomposed wood at 19.5 feet (Boring log continued on Figure 1 b) Client: 0 Gray & Osborne Drilling Method: Y-ID HSA advanced by track -mount Diedrich D-50 Drill Rig Sampling Method: SPT sampler driven by 140-lb auto hammer Drilling Date: December 28, 2009 Drilling Contractor H I D 11 ocene ri ing Figure 1 a S�Bc EE Lake Wa Blvd. Storm & Water Improvement c> z N - 20 2 18 4 18 , 1 I � 1 2 I � I ' � I I ' I � I I - 26 ; ' � I ' I , I 4 18 7 18 � 1 I I I 17 I 1 I ' 1 ' � I 1 1 I ' I —30, I ' 1 I I , I I , I 7 18 7 18 I , I — 35 I I I I I I , , I I 40 ' I I I I I I h a° U j Soil Description sP � Gray fine sand with silt lenses (wet)(loose) - 10 inches silt layer with trace fine gravel at 24 feet sP I Gray fine to medium sand (wet)(medium dense) BORING B-1 (Continued) Boring terminated at a depth of 31.5 feet on December 28, 2009. Groundwater was encountered at a depth of 5 feet during drilling. Client: Gray & Osborne Drilling Method: Y-ID HSA advanced by track -mount Diedrich D-50 Drill Rig Sampling Method: SPT sampler driven by 140-lb auto hammer Drilling Date: December 28, 2009 Drilling Contractor: Holocene Drilling Figure lb SUE Job No.1002 Lake Wa Blvd. Storm & Water Improvement O —0 'O N z° 65 ; BORING B-2 Soil Description 3 18 ,\ 7 3 SM Brown silty fine sand with fine to medium gravel, 8 layers of brown fine to medium sand with fine to medium gravel (pitrun) (damp)(medium dense to loose)(fill) 5 18 7 o a 8 : 18 5 4 4 — 6 , 2 18 3 4 4 sPi Inter -bedded layers of gray fine sand and silt with occasional organics ML (damp)(looselsoft) - 3 18 4 18 \/ 4 2 18 _ 15 3 1a 1 18 2 2U,------'--- (Boring log continued on Figure 2b) Client: Gray & Osborne Drilling Method: Y-ID HSA advanced by track -mount Diedrich D-50 Drill Rig Sampling Method: SPT sampler driven by 140-I1b auto hammer Drilling Date: December 28, 2009 Drilling Contractor: Holocene Drilling Figure 2a SJ& 00E Lake Wa Blvd. Storm & Water Improvement a a BORING HA-1 p ap c; 0 J Soil Description —0 _ I SMI Dark brown silty sand with grass roots (topsoil) ML Gray silt with some organics (wood debris)(very soft) I � I Brown fine to coarse sand with some fine gravel, trace silt (loose)(fill) I I ' kM Gray silt with some organics (wood debris)(very soft) Boring terminated at a depth of 5 feet on December 28, 2009. Subgrade under inches of water. I —10, I ' —15; I I I I I -201_ I I I I Client: Gray & Osborne Drilling Method: 3" diameter hand auger Drilling Date: December 28, 2009 Figure 3 S�8c EE Lake Wa Blvd. Storm & Water Improvement a —0 —6 —10-16 —20 ----- --I -- BORING HA-2 Soil Description Gray and brown silt with some organics (wood debris)(very soft) Brown fine to coarse sand with some fine gravel, trace silt (loose)(fill) Boring terminated at a depth of 7.5 feet on December 28, 2009. Subgrade under 12 inches of water. Client: Gray & Osborne Drilling Method: 3" diameter hand auger Drilling Date: December 28, 2009 Figure 4 SUE Job Lake Wa Blvd. Storm & Water Improvement UNIFIED SOIL CLASSIFICATION SYSTEM W Z DESCRIPTION MAJOR DIVISIONS p' GW WELL -GRADED GRAVELS OR GRAVEL -SAND MIXTURES, CLEAN p, LITTLE OR NO FINES LL N GRAVELS (LITTLE OR Q o`L � °z m U J GP POORLY -GRADED GRAVELS OR GRAVEL -SAND MIXTURES, tf LITTLE OR NO FINES NO FINES) W i Q Q N W > a LL~ w N N w a w w w GM SILTY GRAVELS, GRAVEL -SAND -SILT GRAVELS MIXTURES WITH FINES (APPRECIABLE Q' ~ w w Q Q (� w w,w �o f ° = w p w W <�� Z - o N rye GC CLAYEY GRAVELS, GRAVEL -SAND -CLAY ffff MIXTURES AMOUNT OF FINES) Z F Q LLO I SW WELL -GRADED SAND OR GRAVELLY SANDS, CLEAN pp c ~ a Z U` 2 z LITTLE OR NO FINES SANDS (LITTLE OR 0m Ew <o Oz > W `� ww w W wQ SP POORLY -GRADED SANDS OR GRAVELLY SANDS, LITTLE OR NO FINES NO FINES) w O Z Q< a- U 0O Q O O Y SM <w ~ w J w WwW Ww y)Q O J m Z U _T SILTY SANDS, SAND -SILT MIXTURES SANDS WITH FINES (APPRECIABLE �Q co �// Q'a' JN > ww Op« ,U) 2) a) o' LLJ ]H wO m w SC CLAYEY SANDS, SAND -CLAY MIXTURES AMOUNT OF FINES) cr m ML INORGANIC SILTS, VERY FINE SANDS, ROCK FLOUR, SILTY OR 0> CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY SILTS &CLAYS U w N u J a � c CL INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS a O LIQUID LIMIT LESS THAN 50 w � N Q 2 o o w W z Z °o i� OL ORGANIC SILTS AND ORGANIC SILT -CLAYS OF LOW PLASTICITY ==__===_== ---= - MH INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE Q <Z ~ SANDY OR SILTY SOILS, ELASTIC SILTS <_ = x W CH INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS SILTS & CLAYS W w Z LIQUID LIMIT GREATER THAN 50 afQ u ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, OH ORGANIC SILTS u� PT PEAT AND OTHER HIGHLY ORGANIC SOILS HIGHLY ORGANIC SOILS DEPTH OF STANDARD PENETRATION TEST DEPTH OF UNDISTURBED (SHELBY TUBE) SAMPLE j7 DEPTH OF GROUNDWATER DURING DRILLING SOIL CLASSIFICATION CHART AND KEY TO EXPLORATION LOG S&EE IAPPENDIX B LABORATORY (CONSOLIDATION) TEST RESULTS ' One dimensional consolidation test was performed on a Shelby -tube sample retrieved at a depth of one to three feet at 14A-2 location. The soil sample was transported to our sub -contracted soil laboratory, ' Kleinfelder in Redmond, WA. The test results are included in this appendix. I I 002rpt S&EE Vertical Strain versus Stress Vertical Stress - psf 10 100 1000 10000 100000 0.00 2.00 —- I 4.00 0 c 6.00 N 8.00 10.00 12.00 S&EE Figure B-t Job no. Stress -Strain Curve for Consolidation Test r PROJECT: LOCATION: MATERIAL TYPE: SAMPLE SOURCE: SAMPLE TYPE.: SAMPLE PREP.: REVISED (Y/N)? S.E.E. Unknown. Client submitted. Shelby Tube HA-3 Native Yes N JOB NO: 94046 LAB NO: 9309 DATE SAMPLED: 12/29/2009 PREFORMED BY: B.Kochanski REVIEWED BY: J.Mason One -Dimensional Consolidation Using Incremintal Loading (ASTM D 2435-04) TEST SPECIMEN DATA LIQUID LIMIT: N/A PLASICITY INDEX: N/A BEFORE TEST Wet w+t (g) = 200.66 Dry w+t (g) = 171.56 Tare Wt (g) = 50.45 Height (in) = 1.00 Diameter (in) = 2.50 Moisture = 24.03% Wet Den. (pcf) = 116.57 Dry Den. (pcf) = 93.99 Void Ratio = 0.793 Spec. gray.` = 2.60 Saturation = 81.8% 'Specific gravity assumed Shearing device used: Created by ICON 3.1.3; Copyright 2004, GEOTAC Vertical ress (psf) cv (fOday) 500 0.696299 2000 1.416883 4000 1.370169 8000 0.983066 16000 0.472006 AFTER TEST Wet w+t (g) = 200.66 Dry w+t (g) = 171.56 Tare Wt (g) = 50.45 A Height (in) = 0.13 Height (in) = 0.87 Moisture = 24.03% Wet Den. (pcf) = 134.51 Void Ratio = 0.55 Saturation = 117.1 %