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HomeMy WebLinkAbout04016 - Technical Information Report - Geotechnical 21312 30th Dr. SE, STE. 110, Bothell, WA 98021 | 425.774.0106 | hwageo.com December 4, 2019 HWA Project No. 2018-167-21 KPG 3131 Elliott Avenue, Suite 400 Seattle, Washington 98121 Attention: Kirk Smith, P.E. Subject: GEOTECHNICAL ENGINEERING REPORT NE 16th Street - Jefferson Avenue NE Stormwater Green Connections Renton, Washington Dear Mr. Smith, This letter presents the results of geotechnical engineering studies for the NE 16th Street - Jefferson Avenue NE Stormwater Green Connections project in Renton, Washington. This report includes the results of our field explorations, laboratory testing, evaluation of infiltration feasibility and infiltration rates. The approximate location of the project site is shown on the Vicinity Map, Figure 1, and on the Site Exploration Plans, Figure 2A through 2C. PROJECT UNDERSTANDING It is our understanding that the City of Renton proposes to improve pedestrian mobility, improve stormwater quality and reduce the quantity of stormwater runoff to enhance the neighborhood. Improvements will include bioretention facilities and pervious sidewalks on segments of NE 16th Street and Jefferson Avenue NE. A new curb, gutter, and pervious concrete sidewalk will replace the existing pedestrian path and improve pedestrian safety. A stormwater conveyance system will collect and convey street roadway runoff flow from the underdrain system for the bioretention facilities. Design of these improvements will require evaluation of the subsurface soil conditions and geotechnical recommendations. GEOTECHNICAL SUBSURFACE EXPLORATIONS As part of the initial phase of this project, HWA GeoSciences Inc. (HWA) conducted nine geotechnical borings to evaluate subsurface conditions for the purpose of assessing infiltration potential. The locations of the boreholes are shown on the Site Exploration Plans, Figures 2A through 2C. The borings, designated BH-1 through BH-9, were each drilled to a depth of 11.5 feet below ground surface (bgs) with the exception of boring BH-2 which was drilled to 2 feet bgs due to refusal on concrete. The borings were drilled by Geologic Drill Partners, of Bellevue, December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 2 HWA GeoSciences Inc. Washington, on May 14, 2019 using a limited-access, Bobcat MT52 mounted tracked drill rig equipped with hollow stem augers. In each of the borings, Standard Penetration Test (SPT) sampling was performed using a 2-inch outside diameter split-spoon sampler driven by a 140-pound hammer raised using a rope and cathead. During the SPT, samples were obtained by driving the sampler 18 inches into the soil with the hammer free-falling 30 inches. The numbers of blows required for each 6 inches of penetration were 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. This resistance, or N-value, provides an indication of relative density of granular soils and the relative consistency of cohesive soils; both indicators of soil strength. Following evaluation of the subsurface conditions encountered in the borings, KPG selected three locations for small-scale Pilot Infiltration Testing (PIT). The PITs were completed in July 2019. The PITs were excavated by Harding and Sons, of Duvall, Washington, using a Case CX 80 Tracked Excavator. The PITs were performed at depths between 3 to 3.5 feet. The day following the PIT, the excavations were extended to depths of about 9 feet in order to evaluate receptor soils prior to backfilling. The locations of the PITs are shown on the Site Exploration Plans, Figures 2A through 2C. An HWA geotechnical engineer logged each exploration and recorded all pertinent information. Soil samples obtained from the explorations were classified in the field and representative portions were placed in plastic bags. These soil samples were then taken to our Bothell, Washington, laboratory for further examination and testing. Pertinent information including soil sample depths, stratigraphy, soil engineering characteristics, and ground water occurrence was recorded. The stratigraphic contacts shown on the individual exploration logs represent the approximate boundaries between soil types; actual transitions may be more gradual. The soil and ground water conditions depicted are only for the specific date and locations reported and, therefore, are not necessarily representative of other locations and times. A legend of the terms and symbols used on the exploration logs is presented in Figure A-1. Summary logs of the borehole explorations are presented in Figures A-2 through A-10. Summary PIT logs are presented in Figures A-11 through A-13. LABORATORY TESTING Representative soil samples obtained from the subsurface explorations were taken to the HWA laboratory for further examination and testing. Laboratory tests, as described below, were conducted on selected soil samples to characterize relevant engineering properties of the sampled soils. The tests included visual classifications, natural moisture contents, and grain size distributions. The tests were conducted in general accordance with appropriate American Society of Testing and Materials (ASTM) standards, as described below. The test results are December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 3 HWA GeoSciences Inc. also presented in Appendix B, and/or displayed on the exploration logs in Appendix A, as appropriate. Moisture Content of Soil: The moisture content of selected soil samples (percent by dry mass) was determined in accordance with ASTM D 2216. The results are shown on the logs in Appendix A. Particle Size Analysis of Soils: Selected samples were tested to determine the particle size distribution of material in accordance with ASTM D422 (wet sieve or wet/hydrometer method). The results are summarized on the attached Grain Size Distribution Reports, Figures B-1 through B-7, which also provide information regarding the classification of the samples and the moisture content at the time of testing. SITE DESCRIPTION The site is located in Renton, Washington, east of I-405 as shown on the Vicinity Map (Figure 1). The improvements proposed along NE 16th Street and Jefferson Avenue NE extend from the intersection of Harrington Avenue NE and NE 16th Street to NE 12th Street and Jefferson Avenue NE. Both roadways consist of one travel lane in each direction. Surrounding land use is predominately residential housing with an elementary school north of the intersection of NE 16th Street and Jefferson Avenue NE. The alignment slopes uphill from the intersection of Harrington Avenue NE and NE 16th Street to the high point, just east of the intersection of NE 16th Street and Jefferson Avenue NE. Elevation then descends along Jefferson Avenue NE to the low point of the alignment at the intersection of NE 12th Street and Jefferson Avenue NE. Elevation along the alignment varies from 355 to 383 feet. GENERAL GEOLOGIC CONDITIONS The site is in the central portion of the Puget Sound Lowland, an elongated topographic and structural depression bordered by the Cascade Mountains on the east and the Olympic Mountains on the west. The Lowland is characterized by low-rolling relief with some deeply cut ravines. In general, the ground surface elevation is within 500 feet of sea level. The Puget Lowland was filled to significant depths by glacial and non-glacial sediments during the Pleistocene Epoch, although bedrock does outcrop in scattered locations throughout the area. Generally, the rock is deeply buried by Pleistocene and recent sediments. Geologists have generally agreed that the Puget Sound area was subjected to four or more major glaciations during the Pleistocene Epoch. Ice for these glacial events originated in the Coastal Mountains and the Vancouver Range of British Columbia. The maximum southward advance of ice was about halfway between Olympia and Centralia. The Pleistocene stratigraphic record in the central portion of the Puget Lowland is a complex sequence of glacially-derived and interglacial sediments. Erosion of certain deposits, as well as local deposition of sediments, further complicate the geologic setting. December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 4 HWA GeoSciences Inc. According to the Preliminary Geologic Map of Seattle and Vicinity, Washington (Waldron et. al., 1961), the project vicinity is primarily underlain by glacial till deposits. Glacial till soils were deposited along the sole of the glacial ice. They consist of an unsorted mixture of clay, silt, sand and gravel, which is very dense, having been consolidated by the weight of greater than 2,000 feet of ice. SUBSURFACE SOIL CONDITIONS The soils encountered in our explorations consist of near surface fill soils over recessional outwash and glacial till deposits. Further descriptions of soils encountered in our explorations are presented below in order of deposition, beginning with the most recently deposited. The exploration logs in Appendix A provide more detailed description of subsurface conditions observed at specific locations and depths. Fill: A layer of fill was encountered in borings BH-2, BH-5, BH-6, BH-8 and BH-9 and test pit PIT-3 from ground surface to approximately 1.5 to 6 feet bgs. Minor quantities of organics were observed in the fill. The fill consisted of very loose to medium dense, silty sand with gravel. The fill was likely placed during past grading and construction in the area. Recessional Outwash: Recessional outwash deposits were encountered in test pits PIT-1, PIT-2 and PIT-3 and borings BH-1, BH-3, BH-4 and BH-9. The recessional outwash generally consisted of loose to dense, clean to silty, sand with varying amounts of gravel. Test pit PIT-3 and borings BH-1, BH-3 and BH-9 were terminated in this deposit. Clean sand lenses were observed within this deposit. This unit was deposited in the meltwaters of the receding glacier and therefore is not as dense as glacially overridden deposits. These soils are likely the most feasible for stormwater infiltration. Glacial Till Deposits/Weathered Glacial Till Deposits: Test pits PIT-1 and PIT-2 and borings BH-4, BH-5, BH-6, BH-7 and BH-8 encountered glacial till, typically consisting of medium dense to very dense, silty sand with varying amounts of gravel. Clean sand lenses were observed within this deposit. Interlayered silty sand and clean sand layers were observed in BH-5 within the glacial till deposit. Till was encountered below fill or recessional outwash. Test pits PIT-1 and PIT-2 and borings BH-4, BH-5, BH-6, BH-7 and BH-8 were terminated in glacial till. Locally, the upper portions of the till are weathered, somewhat less dense and finer grained. Glacial till is locally referred to as "hardpan", because of its induration and an appearance similar to concrete. Till is relatively impermeable, except where sandy zones are encountered. Where sand overlies the till, water is often perched on top of the till. Glacial till is also known to contain scattered cobbles and boulders. GROUND WATER CONDITIONS During the explorations in July 2019, no ground water seepage was observed in the test pits (PIT-1 through PIT-3) at the time of excavation. The test pits were excavated in the dry season. December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 5 HWA GeoSciences Inc. No ground water seepage was observed in any of the borings at the time of drilling (May 14, 2019). However, within the weathered till and recessional outwash deposits in borings BH-7, BH-8 and BH-9, oxidation (rust) staining was observed within the soils at depths below 5 feet below ground surface. This suggests that perched water may develop seasonally above the very dense glacial till deposits. We expect that the water is highest during the wet winter months and lowest during the dry summer months. INFILTRATION TESTING HWA conducted three, small-scale Pilot Infiltration Tests (PITs) between July 23 and 26, 2019 in general accordance with the 2017 City of Renton Surface Water Design Manual (SWDM), Reference Section 6-A. The excavations for the PITs were made by Harding and Sons, of Duvall, Washington, under subcontract to HWA. Each test location consisted of an approximate 19 to 23 square foot excavation to a native soil receptor depth, at approximately 3 to 3.5 feet below existing grade. The PIT excavation depth (D) and dimension of width by length (W x L) are as follows, PIT-1: 42 inches (D) by 42 x 78 inches (W x L), PIT-2: 43 inches (D) by 37 x 75 inches (W x L), PIT-3: 36 inches (D) by 38 x 80 inches (W x L). Infiltration testing was conducted by maintaining a stable water level in the excavations. Specific procedures and observations for the PITs are as follows: PIT-1: Water was introduced into the excavation with a garden hose and into a perforated diffuser pipe. Water rose to approximately 1.1 feet above the excavation bottom and remained at that level during the 6-hour presoaking period with the addition of approximately 3 gallons per minute (gpm) of water being introduced. Presoaking was followed by a 1-hour constant head test, with water level readings and instantaneous flow rates taken every 15 minutes. After one hour, the water was shut off and the falling head test was started at 3:15 PM on July 25, 2019, with stage at 1.1 feet. A datalogging level and pressure transducer recorded the fall in stage every 15 seconds and physical readings were also taken during the test. The water level reached the bottom of the excavation approximately 62 minutes after flow was terminated. Short-term hydraulic conductivity, determined using the rates from the falling head test, was approximately 10.7 inches per hour (in/hr). PIT-2: Water was introduced into the excavation with a garden hose and into a perforated diffuser pipe. Water rose to approximately 1.1 feet above the excavation bottom and remained at that level during the 6-hour presoaking period with the addition of approximately 0.2 gpm of water being introduced. Presoaking was followed by a 1-hour constant head test, with water level readings and instantaneous flow rates taken every 15 minutes. After one hour, the water was shut off and the falling head test was started at 3:00 PM on July 24, 2019, with stage at 1.1 feet. A datalogging level and pressure transducer recorded the fall in stage every 15 seconds. After 6.7 hours the water level was still at 0.5 feet in the excavation. Short-term hydraulic conductivity, determined using the rates from the falling head test, was approximately 1 in/hr. December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 6 HWA GeoSciences Inc. PIT-3: Water was introduced into the excavation with a garden hose and into a perforated diffuser pipe. Water rose to approximately 1.1 feet above the excavation bottom and remained at that level during the 6-hour presoaking period with the addition of approximately 3.5 gpm of water being introduced. Presoaking was followed by a 1-hour constant head test, with water level readings and instantaneous flow rates taken every 15 minutes. After one hour, the water was shut off and the falling head test was started at 4:00 PM on July 23, 2019, with stage at 1.1 feet. A datalogging level and pressure transducer recorded the fall in stage every 15 seconds and physical readings were also taken during the test. The water level reached the bottom of the excavation approximately 45 minutes after flow was terminated. Short-term hydraulic conductivity, determined using the rates from the falling head test, was approximately 11.5 in/hr. After infiltration testing was completed, each PIT was over-excavated, and logged as test pits PIT-1 through PIT-3, to depths between 8.8 and 9 feet bgs. The purpose of test pitting through the PIT excavations was to determine adequate vertical separation from ground water/restrictive layers and to retrieve soil samples of the proposed receptor soils for laboratory testing. Ground water seepage or mounding of water was not observed in any test pit excavation. The water level data in feet per date and time for PIT-1 through PIT-3 is presented in Figures 3A through 3C. The falling head test data plotted in feet versus test time in min is presented in Figures 4A through 4B. Summary logs of the test pit explorations are presented in Appendix A, A-11 through -13. More information regarding the PIT procedure and results are presented later in this report. DESIGN RECOMMENDATIONS GENERAL Below any fill soils, the native subgrade soils consist of recessional outwash sands and glacial till (predominately silty sand with varying amounts of gravel). The results of our investigations and laboratory testing indicate that the some of the soils encountered along the project alignments have potential for stormwater infiltration facilities. Pilot Infiltration Tests (PITs) were completed in proposed infiltration locations to determine the design infiltration rates. Our analyses suggest that the beginning and end of the project alignment is suitable for use of onsite infiltration with design infiltration rates between 3.7 and 4.0. However, due to the presence of glacial till near the surface between Stations 17+00 and 24+00 on NE 16th Street and between Stations 70+00 and 81+00 on Jefferson Avenue NE, infiltration is limited to 0.3 in/hr. For permeable sidewalks proposed near glacial till, we recommend a reservoir of clean gravel be provided below the sidewalk to collect water and that an underdrain system be installed to convey excess stormwater to an appropriate outlet or stormwater system. December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 7 HWA GeoSciences Inc. STORMWATER MANAGEMENT AND INFILTRATION RECOMMENDATIONS We understand infiltration of stormwater is desired using bioretention and pervious concrete sidewalks. The depth to the bottom of the facility for bioretention is proposed to be 3 to 3.5 feet bgs. The results of our infiltration feasibility analyses, based on widely spaced subsurface explorations and three Small-Scale Pilot Infiltration Tests (PIT), are described below. Measured Infiltration Rate Small-Scale Pilot Infiltration Testing (PIT) was performed in general accordance with the 2014 Stormwater Management Manual for Western Washington (SWMMWW), published by the Washington State Department of Ecology (Department of Ecology, 2014) and the City of Renton Surface Water Design Manual (Renton, 2017). The infiltration tests were performed at three locations, designated PIT-1 through PIT-3. Based on the test results, the measured infiltration rate from the falling head test are shown below in Table 1. The City of Renton Surface Water Design Manual (Renton, 2017) recommends correction factors be applied to the measured infiltration rate to obtain the design infiltration rate: For pervious pavement and bioretention facilities, the city recommends an Ftesting value of 0.5 be applied based on the number of tests (three) and length of area. Fgeometry is assumed to be 1 since ground water or impervious layers were not observed. Fplugging accounts for reductions in infiltration rates over the long term due to plugging of soils and a value of 0.7 is given for sandy loams. The design infiltration rates are shown below in Table 1 using the correction factors. Table 1. PIT Infiltration Rates Measured Infiltration Rate (in/hr) Design Infiltration Rate (in/hr) PIT-1 10.7 3.7 PIT-2 1.0 0.3 PIT-3 11.5 4.0 Infiltration Summary Our analyses suggest that the beginning and end of the project alignment is suitable for use of onsite infiltration. However, areas where glacial till is present near surface infiltration will be limited due to subsurface soil conditions. Specific recommendations are provided below. • Between Stations 0+00 and 17+00 on NE 16th Street we recommend a design rate of 3.7 in/hr, calculated from PIT-1, be used for bioretention and permeable sidewalk design. December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 8 HWA GeoSciences Inc. • Due to the presence of glacial till near the surface between Stations 17+00 and 24+00 on NE 16th Street and between Stations 70+00 and 81+00 on Jefferson Avenue NE infiltration is limited to 0.3 in/hr. o We recommend that a reservoir of clean granular soils (washed gravel) be placed below the sidewalk in these areas. The reservoir should be sufficiently thick to collect stormwater and convey it to a drainage system. • Between Stations 81+00 and 83+96 on Jefferson Avenue NE we recommend a design rate of 4.0 in/hr, calculated from PIT-3, be used for bioretention and permeable sidewalk design. • Given that ground water seepage was not observed in the field explorations, the minimum 3-foot vertical separation requirement between the ground water and bottom of the infiltration facility is present in areas where infiltration is feasible. Construction Considerations for Infiltration Facilities Prior to the installation of infiltration facilities, the subgrade should be cut to the proposed receptor soil. A flat subgrade is preferred for the bottom of the infiltration facilities. The existing subgrade under areas used for infiltration should NOT be compacted or subjected to excessive construction equipment traffic prior to coarse aggregate bed placement. Where erosion of subgrade has caused accumulation of fine materials and/or surface ponding, this material shall be removed with light equipment and the underlying soils scarified to a minimum depth of 8 inches. Our recommended design infiltration rate assumes that soils will be monitored during trench excavation to ensure low permeability layers or lenses are removed. Subsurface conditions should be monitored and verified during construction by a qualified soil inspector. Construction of the proposed infiltration facilities will require excavations within recessional outwash soils that may contain cobbles and or boulders. Therefore, perspective contractors should be prepared to encounter and remove cobbles and bounders during excavations for the proposed trenches. Temporary Excavations It is our understanding that the proposed storm water facility is to extend approximately 3 to 3.5 feet below existing grade. Sloped excavations and/or standard trench box shoring may be used as means of temporary shoring, if required. The maintenance of safe working conditions, including temporary excavation stability, is the responsibility of the contractor. In accordance with Part N of Washington Administrative Code (WAC) 296-155, latest revisions, all temporary cuts in excess of 4 feet in height must be either sloped or shored prior to entry by personnel. The existing granular soils on site are generally classified as Type C soils, per WAC 296-155. Where shoring is not used, temporary cuts in Type C soils should be sloped no steeper than 1½H:1V (horizontal: vertical). Flatter side slopes could be required for excavations below the water table or where ground water seepage is present. December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 9 HWA GeoSciences Inc. The contractor should monitor the stability of the temporary excavations and adjust the construction schedule and slope inclination accordingly. The contractor should be responsible for control of ground and surface water and should employ sloping, slope protection, ditching, sumps, dewatering, and other measures, as necessary, to prevent sloughing of soils and heave of the bottom of the excavation. CONDITIONS AND LIMITATIONS We have prepared this report for KPG and the City of Renton for use in design of a portion of this project. This report should be provided in its entirety to prospective contractors for bidding and estimating purposes; however, the conclusions and interpretations presented herein should not be construed as a warranty of the subsurface conditions. Experience shows that soil and ground water conditions can vary significantly over small distances. Inconsistent conditions may 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, HWA should be notified to review the recommendations made in this report, and revise, if necessary. If there is a substantial lapse of time between submission of this report and the start of construction, or if conditions change due to construction operations, it is recommended that this report be reviewed to determine the applicability of the conclusions and recommendations considering the changed conditions and time lapse. This report is issued with the understanding that it is the responsibility of the owner, or the owners’ representative, to ensure that the information and recommendations are brought to the attention of the appropriate design team personnel and incorporated into the project plans and specifications, and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field. Within the limitations of scope, schedule and budget, HWA attempted to execute these services in accordance with generally accepted professional principles and practices in the fields of geotechnical engineering and engineering geology at the time the report was prepared. No warranty, express or implied, is made. The scope of our work did not include environmental assessments or evaluations regarding the presence or absence of wetlands or hazardous or toxic substances in the soil, surface water, or ground water at this site. This firm does not practice or consult in the field of safety engineering. We do not direct the contractor’s operations and cannot be responsible for the safety of personnel other than our own on the site. As such, the safety of others is the responsibility of the contractor. The contractor should notify the owner if any of the recommended actions presented herein are considered unsafe.    December 4, 2019 HWA Project No. 2018-167-21 2018-167-21 Letter Report 11 HWA GeoSciences Inc. REFERENCES City of Renton, 2017, Surface Water Design Manual, City of Renton Public Works Department Surface Water Utility, dated December 12, 2016 Waldron, H. et Al., 1961, Preliminary geologic map of Seattle and vicinity, Washington: U.S. Geological Survey, Open-File Report OF-61-168, scale 1:24,000 Washington State Department of Ecology, 2014, Stormwater Management Manual for Western Washington, as Amended in December 2014. VICINITY MAP NE 16TH STREET – JEFFERSON AVENUE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON 1 2018-167-21 FIGURE NO. PROJECT NO. MAP NOT TO SCALE BASE MAP FROM GOOGLE EARTH DATA © 2018 GOOGLE © 2016 Microsoft MDA Geospatial Services Inc. N Approximate Project Location FIGURE NO. PROJECT NO. SITE AND EXPLORATION PLANS NE 16TH STREET- JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON 2A 2018-167-21 BASE PLANS PROVIDED BY KPG FIGURE NO. PROJECT NO. SITE AND EXPLORATION PLANS NE 16TH STREET- JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON 2B 2018-167-21 BASE PLANS PROVIDED BY KPG FIGURE NO. PROJECT NO. SITE AND EXPLORATION PLANS NE 16TH STREET- JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON 2C 2018-167-21 BASE PLANS PROVIDED BY KPG 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 Ground Water Level (ft)Date and Time PIT-1 WATER LEVEL DATA PIT WATER LEVEL DATA 2018-167 FIGURE NO. PROJECT NO. NE 16TH STREET-JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON Start of falling head test (3:15 PM). 3A 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 Ground Water Level (ft)Date and Time PIT-2 WATER LEVEL DATA PIT WATER LEVEL DATA 2018-167 FIGURE NO. PROJECT NO. NE 16TH STREET-JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON Start of falling head test (3:00 PM). 3B 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 Ground Water Level (ft)Date and Time PIT-3 WATER LEVEL DATA PIT WATER LEVEL DATA 2018-167 FIGURE NO. PROJECT NO.NE 16TH STREET-JEFFERSON AVE NESTORMWATER GREEN CONNECTIONS RENTON, WASHINGTON Start of falling head test (4:00 PM). 3C y = -0.0016x + 1.1759 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 Ground Water Level (ft)Time (min) PIT-2 FALLING HEAD TEST WATER LEVEL DATA PIT WATER LEVEL DATA 2018-167 FIGURE NO. PROJECT NO.NE 16TH STREET-JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON Start of falling head test (3:00 PM) 4A y = -0.0162x + 1.0177 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 Ground Water Level (ft)Time (min) PIT-1 FALLING HEAD TEST WATER LEVEL DATA PIT WATER LEVEL DATA 2018-167 FIGURE NO. PROJECT NO.NE 16TH STREET-JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON Start of falling head test (3:15 PM) 4B y = -0.0239x + 0.9648 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 Ground Water Level (ft)Time (min) PIT-3 FALLING HEAD TEST WATER LEVEL DATA PIT WATER LEVEL DATA 2018-167 FIGURE NO. PROJECT NO.NE 16TH STREET-JEFFERSON AVE NE STORMWATER GREEN CONNECTIONS RENTON, WASHINGTON Start of falling head test (4:00 PM) 4C APPENDIX A HWA EXPLORATION LOGS SYMBOLS USED ON EXPLORATION LOGS LEGEND OF TERMS AND to 30 over 30 ApproximateUndrained ShearStrength (psf) <250 250 - No. 4 Sieve Sand with Fines (appreciable amount of fines) amount of fines) More than 50% Retained on No. 200 Sieve Size Sand and Sandy Soils Clean Gravel (little or no fines) More than 50% of Coarse Fraction Retained on No. 4 Sieve Gravel with SM SC ML MH CH OH RELATIVE DENSITY OR CONSISTENCY VERSUS SPT N-VALUE Very Loose Loose Medium Dense Very Dense Dense N (blows/ft) 0 to 4 4 to 10 10 to 30 30 to 50 over 50 ApproximateRelative Density(%) 0 - 15 15 - 35 35 - 65 65 - 85 85 - 100 COHESIVE SOILS Consistency Very Soft Soft Medium Stiff Stiff Very Stiff Hard N (blows/ft) 0 to 2 2 to 4 4 to 8 8 to 15 15 Clean Sand (little or no fines) 50% or More of Coarse Fraction Passing Fine Grained Soils Silt and Clay Liquid Limit Less than 50% 50% or More Passing No. 200 Sieve Size Silt and Clay Liquid Limit 50% or More 500 500 - 1000 1000 - 2000 2000 - 4000 >4000 DensityDensity USCS SOIL CLASSIFICATION SYSTEM Coarse Grained Soils Gravel and Gravelly Soils Highly Organic Soils GROUP DESCRIPTIONS Well-graded GRAVEL Poorly-graded GRAVEL Silty GRAVEL Clayey GRAVEL Well-graded SAND Poorly-graded SAND Silty SAND Clayey SAND SILT Lean CLAY Organic SILT/Organic CLAY Elastic SILT Fat CLAY Organic SILT/Organic CLAY PEAT MAJOR DIVISIONS GW SP CL OL PT GP GM GC SW COHESIONLESS SOILS Fines (appreciable LEGEND 00000.GPJ 2/27/15 Coarse sand Medium sand SIZE RANGE Larger than 12 in Smaller than No. 200 (0.074mm) Gravel time of drilling) Groundwater Level (measured in well or AL CBR CN Atterberg Limits:LL = Liquid Limit California Bearing Ratio Consolidation Resilient Modulus Photoionization Device Reading Pocket Penetrometer Specific Gravity Triaxial Compression Torvane 3 in to 12 in 3 in to No 4 (4.5mm) No. 4 (4.5 mm) to No. 200 (0.074 mm) COMPONENT DRY Absence of moisture, dusty, dry to the touch. MOIST Damp but no visible water. WET Visible free water, usually soil is below water table. Boulders Cobbles Coarse gravel Fine gravel Sand MOISTURE CONTENT COMPONENT PROPORTIONS Fine sand Silt and Clay 5 - 12% PROPORTION RANGE DESCRIPTIVE TERMS Clean Slightly (Clayey, Silty, Sandy) 30 - 50% Components are arranged in order of increasing quantities. Very (Clayey, Silty, Sandy, Gravelly) 12 - 30%Clayey, Silty, Sandy, Gravelly open hole after water level stabilized) Groundwater Level (measured at 3 in to 3/4 in 3/4 in to No 4 (4.5mm) No. 4 (4.5 mm) to No. 10 (2.0 mm) No. 10 (2.0 mm) to No. 40 (0.42 mm) No. 40 (0.42 mm) to No. 200 (0.074 mm) PL = Plastic Limit DD DS GS K MD MR PID PP SG TC TV Dry Density (pcf) Direct Shear Grain Size Distribution Permeability Approx. Shear Strength (tsf) Percent Fines%F Moisture/Density Relationship (Proctor) Approx. Compressive Strength (tsf) Unconfined CompressionUC (140 lb. hammer with 30 in. drop) Shelby Tube Small Bag Sample Large Bag (Bulk) Sample Core Run Non-standard Penetration Test 2.0" OD Split Spoon (SPT) NOTES: Soil classifications presented on exploration logs are based on visual and laboratory observation. Density/consistency, color, modifier (if any) GROUP NAME, additions to group name (if any), moisture content. Proportion, gradation, and angularity of constituents, additional comments. (GEOLOGIC INTERPRETATION) Please refer to the discussion in the report text as well as the exploration logs for a morecomplete description of subsurface conditions. Soil descriptions are presented in the following general order: < 5% 3-1/4" OD Split Spoon with Brass Rings (3.0" OD split spoon) TEST SYMBOLS SAMPLE TYPE SYMBOLS GROUNDWATER SYMBOLS COMPONENT DEFINITIONS NE 16th Street- Jefferson Ave NE Stormwater Green Connections Renton, Washington PROJECT NO.:2018-167-21 A-1FIGURE: GS GS/ HYD S-1 S-2 S-3 S-4 Loose, light yellow brown, silty, SAND, moist. (RECESSIONAL OUTWASH) Loose, yellow brown to olive brown, silty, fine to medium SAND, with scattered gravel, moist. Loose, olive brown, silty, fine to medium SAND, moist. Scattered coarse sand. Minor rust mottling and root debris. Dense, olive brown, slightly rounded gravelly, silty, fine to medium SAND, moist. 1/2" sand lense observed. Dense, olive brown, slightly silty, fine to medium SAND, with scattered coarse sand and gravel, moist. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 5-4-3 2-3-5 14-21-25 10-11-21 SM SM SP SM BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 360 355ELEVATION(feet)BH-1 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-2 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2A DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker SURFACE ELEVATION: 365.0 feet Medium dense to loose, dark brown, silty, fine to medium SAND, moist. Concrete encountered at 2 feet. (FILL/ TOPSOIL) Borehole terminated at 2 feet below ground surface (bgs). Borehole encountered concrete at 2 feet bgs, potential utility. No ground water seepage observed. SM BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 365 360 355ELEVATION(feet)BH-2 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-3 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2A DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker SURFACE ELEVATION: 366.0 feet GS/HYD GS S-1 S-2 S-3 S-4 Medium dense, olive brown, slightly gravelly, silty SAND, moist. (RECESSIONAL OUTWASH) Dense, olive brown, slightly gravelly, silty, fine to medium SAND, moist. Dense, olive gray, slightly gravelly, silty SAND, moist. Clean sand lenses from 1 to 3" thick. Medium dense, olive brown, slightly silty, medium SAND, moist with scattered rounded coarse sand and gravel. Same, sample grades clean. Scattered rounded gravel. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 12-20-21 11-17-13 9-8-8 9-12-18 SM SM SP SM SP BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 375 370 365ELEVATION(feet)BH-3 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-4 Standard Penetration Test DATE COMPLETED: 5/14/2019 DATE STARTED: 5/14/2019DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig SAMPLING METHOD: SPT with Cathead LOCATION: See Figure 2A LOGGED BY: S. Khandaker SURFACE ELEVATION: 379.0 feet GS GS/ HYD S-1 S-2 S-3 S-4 Medium dense, olive gray, slightly silty, fine to medium SAND, moist. (RECESSIONAL OUTWASH) Dense, olive gray, silty SAND, moist. MInor rust mottling with scattered gravel. Dense, olive gray, slightly rounded gravelly, silty, fine to medium SAND, moist. 1/2" sand lense. (WEATHERED TILL) Dense, olive gray, slightly gravelly, silty, SAND, moist. 2" of clean medium sand at toe. Dense, olive gray, silty, fine to medium sandy, rounded GRAVEL, moist. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 11-16-17 7-14-19 15-16-18 13-21-17 SM SM GM BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 375 370ELEVATION(feet)BH-4 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-5 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2B DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker SURFACE ELEVATION: 380.0 feet GS/ HYD GS S-1 S-2 S-3 S-4 4 Inches Hot Mix Asphalt (HMA) Loose, brown, silty, rounded gravelly, fine to medium SAND, moist. Minor organics and rust mottling. (FILL) Medium dense, olive brown, gravelly, silty, fine to medium SAND, moist. Roots and minor rust mottling. Medium dense, olive gray, gravelly, silty, fine to medium SAND, moist. (WEATHERED TILL) Dense, olive gray, silty, rounded gravelly, fine to medium SAND, moist. Clean sand lense at toe of sample. Dense, olive gray, silty, fine to medium SAND, with scattered gravel, moist. 3-4" alternating layers of clean and silty sand. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 6-5-3 4-7-10 18-17-15 9-16-17 SM SM BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 375 370ELEVATION(feet)BH-5 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-6 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2B DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker SURFACE ELEVATION: 380.0 feet GS GS/HYD S-1 S-2 S-3a S-3b S-4 3 Inches Hot Mix Asphalt (HMA) Medium dense, olive gray to yellow brown, gravelly, silty, fine to medium SAND, moist. MInor rust mottling and 1/2" black organics. (FILL) Dense, olive gray- olive brown, gravelly, silty, fine to medium SAND, moist. Minor rust mottling. (WEATHERED TILL) Very dense, olive gray, slightly rounded gravelly, silty, fine to medium SAND, moist. 2" of clean medium sand at toe. (TILL) Low Recovery. Dense, olive gray, gravelly, very silty, fine to medium SAND, moist. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 4-6-6 4-15-16 20-27-30 12-22-24 SM SM SM BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 380 375 370ELEVATION(feet)BH-6 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-7 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2B DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker >> SURFACE ELEVATION: 381.0 feet GS/HYD GS S-1 S-2 S-3 S-4 3-4 Inches Hot Mix Asphalt (HMA) Medium dense, olive brown, slightly gravelly, silty, fine to medium SAND, moist. (WEATHERED TILL) Low Recovery. Medium dense, olive brown, rounded gravelly, very silty, fine to medium SAND, moist. Heavily rust mottled. Low Recovery. Very dense, olive gray, gravelly, very silty, fine to coarse SAND, moist. Sample contains more coarse sand and fine gravel than sample above. (TILL) Dense, olive gray, gravelly, silty, fine to medium SAND, moist. Diamicton observed. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 9-9-9 5-10-11 12-24-35 12-23-25 SM SM BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 375 370ELEVATION(feet)BH-7 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-8 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2C DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker >> SURFACE ELEVATION: 380.0 feet GS/ HYD GS S-1 S-2 S-3 S-4 3 Inches Hot Mix Asphalt (HMA) Very loose, light yellow brown, silty, gravelly, fine to medium SAND, moist. Minor organics and root debris. 2" gravel in sample. (FILL) Dense, olive gray, slightly rounded gravelly. silty, fine to medium SAND, moist. Heavily rust mottled. (WEATHERED TILL) Dense, olive gray, gravelly, silty, fine to medium SAND, moist. 1" clean sand lense observed. Same, sample grades less silty. 1" clean sand lense at toe of sample. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 1-2-1 6-13-17 16-17-16 12-21-22 SM SM BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 365 360ELEVATION(feet)BH-8 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-9 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2C DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker SURFACE ELEVATION: 370.0 feet GS/ HYD GS S-1 S-2 S-3 S-4 4 Inches Hot Mix Asphalt (HMA) Medium dense, light yellow brown, silty, gravelly, fine to medium SAND, moist. (FILL) Low Recovery. Medium dense, olive brown, silty, fine to medium SAND, with scattered gravel, moist. Driller notes gravelly drilling action. (RECESSIONAL OUTWASH) Medium dense, olive gray, slightly silty, fine to medium SAND, moist. Minor rust mottling. Medium dense, gray to olive gray, fine to medium clean SAND, moist. Heavily rust mottled orange at toe. Minor root debris. Borehole terminated at 11.5 feet below ground surface (bgs). No ground water seepage observed. Borehole abandoned with bentonite chips. 3-5-5 4-6-6 9-9-8 5-8-6 SM SM SP SM SP BORING-DSM 2018-167-21.GPJ 5/29/19 FIGURE:PROJECT NO.:2018-167-21 Renton, Washington Stormwater Green Connections NE 16th Street- Jefferson Ave NEDEPTH(feet)0 5 10 15 355 350ELEVATION(feet)BH-9 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid LimitSYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%) NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations. (140 lb. weight, 30" drop) Blows per foot A-10 Standard Penetration Test DATE COMPLETED: 5/14/2019 DRILLING COMPANY: Geologic Drill Partners, Inc. DRILLING METHOD: HWA with Mini BobCat Drill Rig LOCATION: See Figure 2C DATE STARTED: 5/14/2019 SAMPLING METHOD: SPT with Cathead LOGGED BY: S. Khandaker SURFACE ELEVATION: 360.0 feet APPENDIX B LABORATORY TEST RESULTS 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 CLAYSILT 3/4" BH-1 BH-1 BH-3 3" 1-1/2" Fines%PERCENT FINER BY WEIGHT#4 #200 (SM) Light olive-brown, silty SAND (SM) Olive-brown, silty SAND (SM) Olive-brown, silty SAND 0.00050.005 Clay%LL PL GRAVEL 0.05 5/8" 70 #100 0.5 Silt% 4.6 5.7 2.5 - 4.0 5.0 - 6.5 5.0 - 6.5 #10 30 Medium GRAIN SIZE IN MILLIMETERS 50 SAMPLE PI Gravel% 6.4 1.5 6.2 Sand% 18.8 50 74.7 76.5 70.9 17.4 17.1 90 10 DEPTH ( ft.) PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D6913 S-1 S-2 S-2 % MC 11 11 10 Fine Coarse U.S. STANDARD SIEVE SIZES SAND B-1 Coarse #60#40 ASTM SOIL CLASSIFICATION #20 Fine 3/8" 5 SYMBOL 2018-167-21PROJECT NO.: HWAGRSZ SILT-CLAY PERCENTAGE 2018-167-21.GPJ 05/29/19 FIGURE: NE 16th Street- Jefferson Ave NE Stormwater Green Connections Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 CLAYSILT 3/4" BH-3 BH-4 BH-4 3" 1-1/2" Fines%PERCENT FINER BY WEIGHT#4 #200 (SP-SM) Brownish-gray, poorly graded SAND with silt (SM) Brownish-gray, silty SAND (SM) Olive-brown, silty SAND 0.00050.005 Clay%LL PL GRAVEL 0.05 5/8" 70 #100 0.5 Silt% 3.1 7.5 - 9.0 2.5 - 4.0 5.0 - 6.5 #10 30 Medium GRAIN SIZE IN MILLIMETERS 50 SAMPLE PI Gravel% 5.1 2.1 2.6 Sand% 11.3 26.2 50 83.6 71.7 72.7 21.7 90 10 DEPTH ( ft.) PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D6913 S-3 S-1 S-2 % MC 12 10 13 Fine Coarse U.S. STANDARD SIEVE SIZES SAND B-2 Coarse #60#40 ASTM SOIL CLASSIFICATION #20 Fine 3/8" 5 SYMBOL 2018-167-21PROJECT NO.: HWAGRSZ SILT-CLAY PERCENTAGE 2018-167-21.GPJ 05/29/19 FIGURE: NE 16th Street- Jefferson Ave NE Stormwater Green Connections Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 CLAYSILT 3/4" BH-5 BH-5 BH-6 3" 1-1/2" Fines%PERCENT FINER BY WEIGHT#4 #200 (SM) Olive-brown, silty SAND with gravel (SM) Brownish-gray, silty SAND (SM) Olive-brown, silty SAND 0.00050.005 Clay%LL PL GRAVEL 0.05 5/8" 70 #100 0.5 Silt% 4.47.5 - 9.0 10.0 - 11.5 2.5 - 4.0 #10 30 Medium GRAIN SIZE IN MILLIMETERS 50 SAMPLE PI Gravel% 17.3 5.3 14.4 Sand% 21.3 22.9 50 62.7 73.4 62.8 15.6 90 10 DEPTH ( ft.) PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D6913 S-3 S-4 S-1 % MC 9 15 13 Fine Coarse U.S. STANDARD SIEVE SIZES SAND B-3 Coarse #60#40 ASTM SOIL CLASSIFICATION #20 Fine 3/8" 5 SYMBOL 2018-167-21PROJECT NO.: HWAGRSZ SILT-CLAY PERCENTAGE 2018-167-21.GPJ 05/29/19 FIGURE: NE 16th Street- Jefferson Ave NE Stormwater Green Connections Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 CLAYSILT 3/4" BH-6 BH-7 BH-7 3" 1-1/2" Fines%PERCENT FINER BY WEIGHT#4 #200 (SM) Olive-brown, silty SAND (SM) Olive-brown, silty SAND (SM) Olive-brown, silty SAND with gravel 0.00050.005 Clay%LL PL GRAVEL 0.05 5/8" 70 #100 0.5 Silt% 4.9 5.8 7.5 - 8.8 2.5 - 4.0 10.0 - 11.5 #10 30 Medium GRAIN SIZE IN MILLIMETERS 50 SAMPLE PI Gravel% 3.6 7.5 25.3 Sand% 20.6 50 74.2 60.2 54.1 17.3 26.5 90 10 DEPTH ( ft.) PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D6913 S-3a S-1 S-4 % MC 12 11 10 Fine Coarse U.S. STANDARD SIEVE SIZES SAND B-4 Coarse #60#40 ASTM SOIL CLASSIFICATION #20 Fine 3/8" 5 SYMBOL 2018-167-21PROJECT NO.: HWAGRSZ SILT-CLAY PERCENTAGE 2018-167-21.GPJ 05/29/19 FIGURE: NE 16th Street- Jefferson Ave NE Stormwater Green Connections Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 CLAYSILT 3/4" BH-8 BH-8 BH-9 3" 1-1/2" Fines%PERCENT FINER BY WEIGHT#4 #200 (SM) Light olive-brown, silty SAND (SM) Olive-brown, silty SAND with gravel (SM) Yellowish-brown, silty SAND 0.00050.005 Clay%LL PL GRAVEL 0.05 5/8" 70 #100 0.5 Silt% 3.0 1.9 5.0 - 6.5 7.5 - 9.0 2.5 - 4.0 #10 30 Medium GRAIN SIZE IN MILLIMETERS 50 SAMPLE PI Gravel% 11.4 15.6 13.5 Sand% 25.3 50 70.5 59.1 69.8 15.1 14.8 90 10 DEPTH ( ft.) PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D6913 S-2 S-3 S-1 % MC 8 11 7 Fine Coarse U.S. STANDARD SIEVE SIZES SAND B-5 Coarse #60#40 ASTM SOIL CLASSIFICATION #20 Fine 3/8" 5 SYMBOL 2018-167-21PROJECT NO.: HWAGRSZ SILT-CLAY PERCENTAGE 2018-167-21.GPJ 05/29/19 FIGURE: NE 16th Street- Jefferson Ave NE Stormwater Green Connections Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 CLAYSILT 3/4" BH-9 3" 1-1/2" Fines%PERCENT FINER BY WEIGHT#4 #200 (SP-SM) Olive-brown, poorly graded SAND with silt 0.00050.005 Clay%LL PL GRAVEL 0.05 5/8" 70 #100 0.5 Silt% 7.5 - 9.0 #10 30 Medium GRAIN SIZE IN MILLIMETERS 50 SAMPLE PI Gravel%Sand% 9.0 50 91.0 90 10 DEPTH ( ft.) PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D6913 S-3 % MC 10 Fine Coarse U.S. STANDARD SIEVE SIZES SAND B-6 Coarse #60#40 ASTM SOIL CLASSIFICATION #20 Fine 3/8" 5 SYMBOL 2018-167-21PROJECT NO.: HWAGRSZ SILT-CLAY PERCENTAGE 2018-167-21.GPJ 05/29/19 FIGURE: NE 16th Street- Jefferson Ave NE Stormwater Green Connections Renton, Washington