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23_RS_BW_Geotechnical_Report_210927_v1
20212729.001A/SEA21R130976 Page i of iv September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com GEOTECHNICAL ENGINEERING REPORT BURNETT AVE SOUTH AND WILLIAMS AVE SOUTH WATER QUALITY RETOFIT PROJECT RENTON, WASHINGTON KLEINFELDER PROJECT # 20212729.001A SEPTEMBER 27, 2021 Copyright 2021 Kleinfelder All Rights Reserved ONLY THE CLIENT OR ITS DESIGNATED REPRESENTATIVES MAY USE THIS DOCUMENT AND ONLY FOR THE SPECIFIC PROJECT FOR WHICH THIS REPORT WAS PREPARED. 20212729.001A/SEA21R130976 Page ii of iv September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com A Report Prepared for: Becca Ochiltree, PE Project Manager BHC Consultants 1601 Fifth Avenue Suite 500 Seattle, WA 98101 GEOTECHNICAL ENGINEERING REPORT BURNETT AVE SOUTH AND WILLIAMS AVE SOUTH WATER QUALITY RETOFIT PROJECT RENTON, WASHINGTON William R. Rosso, EIT Professional Marcus B. Byers, PE, P.Eng Principal Geotechnical Engineer Senior Project Manager KLEINFELDER 14710 NE 87th Street, Suite 100 Redmond, WA 98052 p | 425.636.7900 f | 425.636.7901 September 27, 2021 Kleinfelder Project No.:20212729.001A 20212729.001A/SEA21R130976 Page iii of iv September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com TABLE OF CONTENTS Section Page 1 INTRODUCTION AND SCOPE ....................................................................................... 1 1.1 GENERAL............................................................................................................ 1 1.2 PROJECT UNDERSTANDING ............................................................................ 1 1.3 SCOPE OF SERVICES ....................................................................................... 1 1.3.1 Task 1 – Field Investigation ...................................................................... 2 1.3.2 Task 2 – Laboratory Testing ..................................................................... 3 1.3.3 Task 3 – Geotechnical Analyses and Report ............................................ 3 2 SITE CONDITIONS ......................................................................................................... 4 2.1 SURFACE CONDITIONS .................................................................................... 4 2.2 GEOLOGIC SETTING ......................................................................................... 4 2.3 EXISTING GEOTECHNICAL DATA ..................................................................... 5 2.4 SUBSURFACE CONDITIONS ............................................................................. 6 2.4.1 Soils ......................................................................................................... 6 2.4.2 Pavements ............................................................................................... 8 2.4.3 Groundwater ............................................................................................ 8 3 GEOLOGIC HAZARDS ................................................................................................... 9 4 GEOTECHNICAL CONCLUSIONS AND RECOMMENDATIONS ................................ 10 4.1 GENERAL.......................................................................................................... 10 4.2 EXCAVATIONS ................................................................................................. 11 4.2.1 General .................................................................................................. 11 4.2.2 Excavation Conditions and Obstructions ................................................ 12 4.2.3 Settlement Monitoring............................................................................. 12 4.2.4 Temporary Slopes .................................................................................. 12 4.2.5 Temporary Shoring ................................................................................. 13 4.3 DEMOLITION .................................................................................................... 15 4.4 PAVEMENTS ..................................................................................................... 16 4.5 EARTHWORK ................................................................................................... 17 4.5.1 Trench and Manhole Subgrades ............................................................ 17 4.5.2 Weather Considerations ......................................................................... 18 4.5.3 Structural Fill Materials ........................................................................... 19 4.5.4 Structural Fill Placement and Compaction .............................................. 20 4.5.5 Construction Dewatering ........................................................................ 20 4.6 ENVIRONMENTAL FIELD SCREENING ........................................................... 21 5 LIMITATIONS ............................................................................................................... 22 6 REFERENCES .............................................................................................................. 24 20212729.001A/SEA21R130976 Page iv of iv September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com FIGURES 1 Site Vicinity Map 2 Site and Exploration Plan APPENDICES A Boring Logs B Geotechnical Laboratory Testing C Boring Logs for Prior Studies 20212729.001A/SEA21R130976 Page 1 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 1 INTRODUCTION AND SCOPE ___________________________________________________________________________________ 1.1 GENERAL This report presents the results of Kleinfelder’s geotechnical engineering study and limited environmental field screening for the proposed water quality retrofit project planned by the City of Renton. The proposed retrofit project is in the Williams Sub-Basin, which includes areas along Burnett Avenue South and Williams Avenue South between the Cedar River and South 2nd Street, including South Tillicum Street and South Tobin Street. Figure 1, Site Vicinity Map, and Figure 2, Site Exploration Plan, show the project location and the approximate Williams Sub-Basin boundary. 1.2 PROJECT UNDERSTANDING We based our project understanding on discussions with Becca Ochiltree of BHC Consultants (BHC) and Amanda Pierce of the City of Renton (the City), as well as 30% drawings dated September 15, 2021. We understand that replacement, rehabilitation, and/or upsizing of the stormwater utilities is being considered to improve outflow water quality and increase system capacity. The City plans to upgrade the existing stormwater infrastructure and retrofit water quality treatment facilities within the Burnett and Williams sub-basin. Based on a review of the City of Renton’s Maps and GIS Data, existing storm water system depths are generally between about 2 to 5 feet below the existing ground surface. The 30% drawings indicate that the upsized storm water lines in Burnett Avenue South will have invert depths of about 4 feet below the ground surface, while the line in South Tobin Street will vary from about 7 to 9 feet deep, and the line in Williams Avenue South will gradually increase from about 5 feet at the south end of the alignment to 12 feet at the north end of the alignment where it ties into the outfall. 1.3 SCOPE OF SERVICES The scope of our geotechnical study consisted of a site reconnaissance and subsurface exploration, limited environmental screening, geotechnical engineering analysis, laboratory testing, and this report. Complete studies to assess regional groundwater behavior and 20212729.001A/SEA21R130976 Page 2 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com environmental hazards that may affect the soil and/or groundwater at the site were beyond our scope of services. The following sections present describe our services performed. 1.3.1 Task 1 – Field Investigation On September 2, 2020, Kleinfelder performed a preliminary site walk and surficial reconnaissance to observe the conditions of the project area and evaluate access for exploration equipment. During the site walk we observed that both Burnett and Williams Avenue are both two lane, one- way streets with on-street parking on the east and west sides of each road. Based on this site walk and discussions with BHC, we decided to advance the boring closest to the outfall in the roadway at the northwest corner of South Tillicum and Williams Avenue, rather than in landscape area, concluded that all planned borings could be readily accessed with a track-mounted drill rig. Due to the presence of a 104-inch diameter King County sanitary sewer and numerous other underground and overhead utilities, borings were not conducted in Burnett Ave South. Prior to drilling, we notified the One-Call Utility locate services as required by the state of Washington so that the member utility companies could mark their facilities. We were notified that Puget Sound Energy (PSE) has a high-pressure gas line in the vicinity of our borings and that an on-site meeting would be required prior to drilling in order to allow PSE to approve our proposed locations. A Kleinfelder representative met on site with representatives from both PSE and the City, who verified that the proposed boring locations would be a sufficient distance from the marked utilities. BHC and the City of Renton coordinated review of our boring locations and plan by the Washington State Department of Ecology (WADOE). Prior to beginning drilling the boring locations were scanned by a private utility locator for conductible utilities and non-conductible underground structures using ground penetrating radar. During these sweeps, a small unmarked or possibly abandoned underground structure was found on South Tobin Street, but was not close enough to impact our borings. We completed the drilling program on February 4, 2021. Borings were advanced by our subcontracted driller, Holocene Drilling, using a Diedrich D-50 rubberized track rig. Three hollow-stem auger (HSA) borings were advanced to a depth of 20 feet below the existing ground surface (bgs) and one to a depth of 30 feet bgs (the boring nearest the Cedar River outfall). Soil sampling consisted of standard penetration test (SPT) samples collected at 2½-foot intervals in the first 10 feet and 5-foot intervals thereafter. At boring KB-1, near the outfall, the first 7½ feet 20212729.001A/SEA21R130976 Page 3 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com was cleared using a truck-mounted vacuum and air knife due to the proximity of the high-pressure gas line. During drilling the soil samples were field screened for organic vapors using a field calibrated photoionization detector (PID). Samples collected during drilling were stored in plastic bags and delivered to Kleinfelder’s laboratory for testing. Appendix A presents the summary boring logs, which provide additional information on the soils encountered and the PID readings. Borings were backfilled with bentonite chips to approximately 4 feet below the top of the existing asphalt road surface. The asphalt surface at each location was then repaired by the driller by filling the remaining 4 feet with concrete, which was mixed with black dye near the surface and troweled to be flush with the roadway. Soil cuttings generated by the borings were placed into drums. Since we did not observe visible indication of contamination or elevated PID readings the drummed cuttings were deemed “clean” and hauled off-site. 1.3.2 Task 2 – Laboratory Testing Laboratory testing was conducted on selected representative samples obtained from the borings to help characterize the site soils and relevant engineering and index properties. Laboratory testing included natural moisture content, grain-size distribution, and Atterberg limits. Tests were conducted in general accordance with appropriate American Society for Testing and Materials (ASTM) Standards and results can be found in Appendix B. 1.3.3 Task 3 – Geotechnical Analyses and Report We prepared this report based on the results of our field and laboratory programs, and the planned improvements. 20212729.001A/SEA21R130976 Page 4 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 2 SITE CONDITIONS ___________________________________________________________________________________ 2.1 SURFACE CONDITIONS The proposed improvements are located near the downtown Renton area, approximately bounded by the Cedar River to the north, South Second Street to the south, Burnett Place South to the west, and Williams Avenue South to the east, as shown on the Vicinity Map, Figure 1. The existing infrastructure along these streets primarily consists of single-family residences, a limited number of single-story commercial buildings, and two multistory apartment complexes. Topography in the area is generally flat and elevations in the vicinity of the improvements range from about Elevation 36 to 40 feet above mean sea level (WGS84), except for the banks of the Cedar River, which slope down to the river at about Elevation 25 feet. During our site visits we observed that the banks of the Cedar River appear to have been lined with rip rap rock and geotextile fabric. The existing outfall is located on the south bank of the Cedar River, to the west of the Williams Avenue Bridge. We were unable to be observe the outfall during our site walks due to it being obscured by the rip rap and vegetation. 2.2 GEOLOGIC SETTING The project area is located in the central portion of the Puget Lowlands, an elongated, north-south depression situated between the Olympic Mountains and the Cascade Range. Repeated glacial advances (glacial events) into this region strongly influenced present-day topography, geology, and groundwater conditions in the project area. Puget Lowlands consist of a variety of soils from glacially overridden lacustrine deposits to outwash and glacial drift deposits. Fine grained and course grained alluvium and flood plain deposits, volcanic mudflows, and landslide materials are all present in the general project vicinity. Based on the Washington Department of Natural Resources Interactive Geologic Map (1:250,000 scale), surficial soils at the site are anticipated to consist of fill. Fill may consist of well compacted material free of organics (engineered fills) or poorly compacted materials containing organics, timbers, debris, and other unknown objects (undocumented fills). The anticipated thickness of the fill layer varies but may be on the order of 10 feet where present. Mapping at the 1:500,000 scale indicates that the project area is underlain by a variety of native soils ranging from alluvium to 20212729.001A/SEA21R130976 Page 5 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com till-like glacial drifts. The alluvium materials, interbedded silty sands and sandy silts with organic silts and peat, likely range from 50 to 80 feet thick. Below this, soils are anticipated to transition into glacial drift deposits, which consist of till-like dense sandy gravel and gravelly sand, with cobbles and boulders strewn within. The geology for portions of the site is impacted by the diversion of the Cedar River in 1912. In 1911 there was a major flood along the lower Cedar River that prompted the city of Renton to divert the river directly into Lake Washington, which created the current channel location. Our Site and Exploration Plan, Figure 2, depicts the approximate former channel the Cedar River, which underlies the northeast portion of the project area. The borings were advanced within the old Cedar River channel and boring KB-1, located near the outfall, encountered buried timber starting at approximately 25 feet bgs. Based on a review of available data for the downtown Renton area, groundwater ranges from as shallow as 4 feet bgs to as deep as 20 feet bgs. The depth to groundwater is expected to vary with seasonal changes in rainfall and surface runoff, impacts of local development, and the level of the Cedar River. 2.3 EXISTING GEOTECHNICAL DATA Between September of 2017 and March of 2020 Kleinfelder performed a variety of tasks as the environmental and geotechnical engineering consultant for the City of Renton’s Downtown Utility Improvement Plan (DUIP). These tasks included a review four prior geotechnical reports authored by others for developments within the downtown Renton area; a desktop study the of existing geologic information; three phases of field explorations to evaluate soil and groundwater conditions within the project area; a Phase I environmental desktop study; and a Phase II environmental field exploration to further evaluate potentially impacted soils within the project area. Two prior Kleinfelder borings for the DUIP study, KB-04 and MW-5, are located at the southeast and southwest corners of the Williams sub-basin and are referenced for this report. Our report for the DUIP, and the other prior development reports, describe similar soil units and conditions to those encountered in our borings for this project. These reports generally describe about 10 feet of fill comprised of soft silts and loose sands, but the fill depths ranged from as shallow as 3 feet and to as deep as 20 feet below the existing ground surface. Below the fill, borings encountered alluvium, which included loose to medium dense silty sands, gravels, and possible cobbles and boulders. The alluvium deposits generally became dense at around 20 to 20212729.001A/SEA21R130976 Page 6 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 30 feet bgs and extended to the boring termination depths of up to 50 feet bgs. Some borings within the vicinity of Rainier Avenue South and South Second Street also encountered sandstone or siltstone bedrock at approximately 20 to 30 feet bgs. Groundwater monitoring wells installed along South 2nd Street and South 3rd Street monitored from April 2019 through January 2020 indicated groundwater levels between about 10 and 13 feet below the existing ground surface. Groundwater levels were generally slightly shallower, about 7 feet bgs, near Rainier Avenue South and deepened to about 15 feet closer to the Cedar River. In MW-5, located at the southwest corner of the Burnett and Williams project boundary, observed groundwater levels ranged from about 14 to 17 feet bgs. Reported pavement sections varied from asphalt with an aggregate base course to asphalt over concrete with an aggregate base course, and in a few borings brick pavement was encountered beneath the asphalt or aggregate base course. Asphalt thicknesses were generally about 4 to 6 inches, but ranged from 2½ to 12 inches. Concrete thicknesses were generally about 4 to 8 inches. Pavement sections with brick were only encountered along South 3rd Street. The prior reports noted the presence of potentially caving soils and shallow groundwater seepage, as well as the presence of potentially liquefiable soils below the water table. One report noted that an existing building located southeast of the Burnett and Williams project boundary experienced severe post-construction settlement and cautions to avoid strong ground vibrations during construction and demolition. This report also recommended settlement monitoring be performed on the nearby existing building during construction and that an existing-condition and post-construction survey be performed. These recommendations are important to consider for the Burnett and Williams Water Quality Upgrades project, and emphasize the importance of considering an existing-condition survey prior to construction and performing settlement monitoring, depending on the nature and location of planned construction activities relative to existing infrastructure. 2.4 SUBSURFACE CONDITIONS 2.4.1 Soils Based on our review of existing geotechnical data and the conditions encountered in our borings, soils along the alignment are somewhat variable. Historical events such as the diversion of the Cedar River, lowering the level of Lake Washington, and land modification associated with 20212729.001A/SEA21R130976 Page 7 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com development have had a significant impact on this site’s topography and surface geology. We have characterized soils encountered in the borings in generalized units for the purpose of discussion, which are described below in the order encountered. The summary boring logs in Appendix A and Appendix C present more detail relative to the subsurface conditions observed at specific locations. • Fill: Fill was encountered just below the pavement sections and generally ranged from about 7½ to 15 feet thick. Borings KB-1 through KB-3, located in Williams Avenue South and South Tobin Street, encountered a mix of silts and sands with varying amounts gravel, likely placed to fill the historical Cedar River channel. Borings KB-4, in the alley south of Williams Avenue South, encountered gravel with varying amounts of silt and sand, likely placed more recently as backfill for the below grade portion of the nearby apartments. Moisture contents ranged from about 4 to 7 percent within the gravel fill soils and from about 8 to 33 percent in the silty fill soils. SPT N-Values within the silty fill soils generally ranged from 2 to 4 blows per foot, which correlates to a consistency of loose to medium stiff. SPT N-Values within the granular fill soils found in KB-4 ranged from 7 blows per foot near the surface to 38 blows per foot above the alluvium, which correlates to a loose to dense consistency. • Alluvium: These soils were encountered below the fill in each of our borings and extended to their termination depths. They were comprised of a mix of fine to coarse sands and gravels with varying silt contents. Moisture contents ranged from about 5 to 28 percent but were generally about 6 to 10 percent. SPT N-Values within the alluvium were between 11 to 36 blows per foot, which correlates to medium dense to dense sands and gravels. The granular soils in this unit are considered water bearing. The higher moisture contents observed in some samples from KB-1 are likely reflective of some of the organic deposits mixed in with the alluvium as described below. • Buried Timber/Logs: Boring KB-1 encountered pieces of buried wood (interpreted as timber or logs) at depths of approximately 25 and 30 feet bgs. KB-1 is located within the former Cedar River channel and this material is likely associated with deposits from before the river was diverted. Our review of prior reports noted similar materials at depths between 20 to 30 feet bgs in other borings, and the area is known for potential buried logs. If the planned project changes such that deeper utilities or an outfall are included, or temporary shoring is planned to penetrate below 20 feet, construction means and methods should account for potential obstructions due to timber and logs. In addition, if utilities or 20212729.001A/SEA21R130976 Page 8 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com structures need to be founded below about 15 feet bgs, Kleinfelder should be contacted to discuss options to mitigate potential settlement associated with the organic material. 2.4.2 Pavements Borings in the roadways encountered asphaltic concrete pavement sections approximately 3 to 4 inches thick with approximately 4 to 6 inches of base course. At boring KB-4, located in the alleyway between Burnett Ave and Williams Ave, the asphalt pavement was approximately 2 inches thick with approximately 6 inches of base course comprised of what appeared to be recycled concrete. 2.4.3 Groundwater Groundwater levels observed during drilling were generally about 15 feet bgs. Groundwater monitoring was performed at MW-5, installed previously as part of the DUIP project, approximately once a month from April 2019 through January 2020. Groundwater levels within this monitoring well ranged from about 14.3 feet bgs in January of 2020 to 17.8 feet bgs in August of 2019. Perched groundwater conditions may develop seasonally, particularly overlying fine-grained soils or in sand seams and may be encountered at shallower depths than those encountered in our borings. The groundwater conditions reported above are for the specific dates and locations indicated and, therefore, may not necessarily be indicative of other times and/or locations. It is anticipated that ground water conditions will vary depending on the season, rate and duration of recent precipitation, local subsurface conditions, the level of the Cedar River, and other factors. A detailed investigation of regional groundwater conditions was outside the scope of our study. 20212729.001A/SEA21R130976 Page 9 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 3 GEOLOGIC HAZARDS ___________________________________________________________________________________ The site is located in moderate to high liquefaction susceptibility hazard area per King County Flood Control District Map 11-5 Liquefaction Susceptibility. Soil liquefaction is a condition where saturated, granular soils undergo a substantial loss of strength due to pore pressure increase from cyclic stress induced by earthquakes. In the process, the soil may undergo horizontal displacements (lateral spreading) and vertical settlement. Utility damage caused by liquefaction and lateral spreading include, but is not limited to, pulled / broken connections, pipe breakage, loss of gravity flow due to vertical displacement, and uplift or floatation, particularly in manhole structures that extend below the groundwater table. Areas along the project alignment are relatively flat and are generally not considered susceptible to landslide or seismically induced slope failures. 20212729.001A/SEA21R130976 Page 10 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 4 GEOTECHNICAL CONCLUSIONS AND RECOMMENDATIONS ___________________________________________________________________________________ 4.1 GENERAL General conclusions and recommendations developed based on the results of our exploration and analysis are summarized below and detailed in the following sections. • The contractor will be responsible for selecting appropriate means and methods to accomplish the utility installation. It is important that means and methods consider many factors, including but not limited to, the factors discussed in this report, and summarized below: o Variable soil conditions including soft fine-grained soils, loose granular soils, dense granular soils, and buried timber; and, o The need to dewater or control groundwater for deeper utilities while also limiting groundwater drawdown and preventing settlement of existing utilities and structures. • Excavations for utility installation will be made adjacent to existing utilities, structures or pavements that are to remain and require protection. Site soils, particularly the weaker (soft/loose) soils, and soils below the groundwater table, are highly susceptible to sloughing, raveling, and flowing. Positive support of soils in the trench walls will be required in many areas in order to limit disturbance beyond the trench. • Excavations located away from existing utilities, structures or pavements that will remain in place can be sloped when made above the ground water table, but this will require a larger excavation volume and increased pavement restoration areas, and may not accommodate traffic lanes that must remain open. • Excessive vibrations may cause ground settlement, and corresponding settlement and damage to nearby utilities and buildings if proper precautions are not taken. Use of vibratory methods to install shoring should be evaluated carefully and appropriate pre-condition surveys, vibration monitoring, and settlement monitoring should be performed. 20212729.001A/SEA21R130976 Page 11 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com • The contractor will need to carefully evaluate shoring means and methods for accomplishing the work. We anticipate that a combination of structural and non-structural shoring methods may be required. Structural shoring, as defined in Section 2-09.3(3) D of the WSDOT Standard Specifications, is a shoring system that is installed prior to excavation and provides lateral support of soils to limit lateral movement. Non-structural shoring, which is installed after excavation, may provide worker protection, but typically allows some soil movement and does not provide the same level of protection for existing infrastructure. • We recommend settlement monitoring points and a pre-construction survey of buildings be discussed with the project team as it may be appropriate to establish them along the existing utilities and structures. A suggested rule of thumb would be to monitor and survey buildings where the distance from the edge of the excavation to the building is less than the depth of the excavation. • We understand current WSDOT/APWA Standard Specifications will be used for this project along with City of Renton Standard Details. 4.2 EXCAVATIONS 4.2.1 General Given the anticipated depth of the utilities and treatment facilities (about 5 to 12 feet bgs) we anticipate that shoring requirements for this project will likely be non-structural as defined in Section 2-09.3(3) D of the WSDOT Standard Specifications and that sumps and pumps will be sufficient to deal with nuisance groundwater seepage into excavations. If excavations extend beyond about 15 feet below the existing ground surface the contractor will need to carefully evaluate the combination of shoring (structural vs non-structural) and dewatering methods for accomplishing the work. Considerations should focus on, but not be limited to, worker safety and protection of the existing buildings and utilities. Structural shoring provides support prior to excavation to limit lateral movement and can include a variety of methods, some of which are discussed in in Section 4.2.5.1. Non-structural shoring could include trench boxes or other systems, which are installed after the excavation is completed. These systems may provide worker protection, but typically allow soil movement, do not provide the same level of protection for existing infrastructure, and will be difficult to install in soils that do not stand unsupported. Some of these methods are discussed in Section 4.2.5.2. 20212729.001A/SEA21R130976 Page 12 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 4.2.2 Excavation Conditions and Obstructions We anticipate that excavation of the on-site fill and alluvial deposits can be performed with conventional earthmoving equipment. Buried logs or timber, construction debris, concrete slabs or utilidors may be encountered during excavation activities. While not anticipated, if old piles or abandoned concrete utility ducts are encountered, they should be cut off at least 3 feet below trench subgrade level. The contractor should anticipate the excavation, removal, and replacement of these materials with compacted structural fill as recommended in Sections 4.5.3 and 4.5.4. Due to the numerous utilities existing on site, potholing should be performed to identify existing utility locations prior to beginning excavations. Hand excavation and/or use of a vacuum truck may be advantageous when excavating around some utilities. 4.2.3 Settlement Monitoring While not currently anticipated, if excavations for utilities will be performed close to existing buildings or groundwater draw down due to construction dewatering will exceed about 5 feet, consideration should be given to settlement monitoring. As a general rule of thumb, if utility excavations will be within a horizontal distance from a structure equal to or less than the depth of the excavation, consideration should be given to monitoring the structure. Kleinfelder should be contacted to review conditions on a case-by-base basis as the project plans are developed. 4.2.4 Temporary Slopes All excavations and slopes must comply with applicable local, state, and federal safety regulations including the current OSHA Excavation and Trench Safety Standards and WISHA Safety Standards for Construction Work. Construction site safety is the sole responsibility of the Contractor, who shall also be solely responsible for the means, methods, and sequencing of construction operations. Most of the on-site soils should be considered as Type C soils, which should be inclined no steeper than 1½H:1V. However, some of the site soils are soft / loose and may require even flatter sloping to be stable and safe. The above recommendations are for excavations made above the groundwater table. Excavations made below the groundwater table should be shored. Due to proximity to utilities and the need to maintain some traffic lanes in roadways, sloping of excavations may be impractical. 20212729.001A/SEA21R130976 Page 13 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com Temporary slopes should be protected from the elements by covering with plastic sheeting or similar means. Sheeting sections should overlap by at least 12 inches and be tightly secured with sandbags, tires, staking, or other means to prevent wind from exposing the soils under the sheeting. Heavy equipment, building materials, excavated soil, and vehicular traffic should not be allowed near the top of any sloped temporary excavation. 4.2.5 Temporary Shoring Where the stability of adjoining buildings, walls, utilities, or other structures is endangered by excavation operations, support systems such as shoring, bracing, or underpinning may be required to provide structural stability and to protect personnel working within the excavation. If earth retention, structural-shoring, bracing, or underpinning are used for the project they should be designed by a professional engineer registered in the State of Washington. Temporary shoring should be utilized where sloping excavations is not practical. Excavations that are adjacent to existing utilities, structures or pavements that are to remain should be shored to prevent ground loss or movement and potential damage to the existing utilities or structures. 4.2.5.1 Structural Shoring Structural shoring includes systems that are installed and provide soil support prior to excavation per Section 2-09.3(3) D of the WSDOT Standard Specifications. Some examples of structural shoring systems include driven cantilever sheet piles; sheet piles with tiebacks, wale rings or struts; cantilever soldier piles with lagging and soldier piles with lagging and tiebacks. Structural shoring may be required due to the proximity of existing utilities or structures, due to weak soils that cave or slough rapidly, to limit areas of disturbance, or other factors. Based on the currently proposed improvements and relatively limited depths, structural shoring may only be required at the deeper structures, if at all; selection of the shoring system is ultimately a contractor means and methods decision. The following sections present a short discussion of two potential structural shoring options and are not intended to limit the contractor’s available means and methods for structural shoring. 20212729.001A/SEA21R130976 Page 14 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com Sheet Piles Due to potential for vibration induced settlement, construction of a sheet pile shoring system using impact and conventional vibratory hammers are not recommended. However, sheet piles installed using a variable eccentric moment hammer could be considered. A vibratory hammer with a variable eccentric moment can be started and stopped with much lower vibration levels than with conventional hammers, which can allow sheet piles to be installed near settlement sensitive structures such as buildings and nearby utilities. The sheet pile shoring system could be either cantilever or braced depending on the required excavation height and groundwater levels. One potential issue with a sheet pile shoring system would be the relatively deep embedment required to cut off groundwater flow to meet base heave stability requirements. Dense gravels encountered at depth may also prevent sheets from being driven to the design tip elevation or cause them to be driven out of interlock thereby allowing seepage and soil movement into the excavation. Sheet pile embedment requirements for groundwater cutoff could be reduced by installing a jet grout cut-off barrier below the minimum required tip for structural considerations or by using a dewatering / depressurization system. Soldier Piles and Lagging Soldier piles can be installed in conventional drilled holes, but temporary casing and use of a slurry and/or water surcharge to control bottom heave should be anticipated for installation especially below the groundwater table. For solider piles that are vibrated into place without a drilled hole, vibrations should be controlled in a similar manner as discussed above by use of a variable eccentric moment hammer. Timber or steel sheets can be used for lagging, but the system should not be considered watertight and there will be significant risk of running / flowing sands entering the excavation unless dewatering is performed prior to excavation. Grouting or other ground improvement methods could be utilized prior to excavation to control groundwater flows and improve soil stability. Base heave stability requirements discussed above may also be a controlling factor in design of soldier pile shoring. 20212729.001A/SEA21R130976 Page 15 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 4.2.5.2 Non-Structural Shoring Non-structural shoring includes systems that don’t meet the definition of structural shoring and can be divided into two general categories: shielding and shoring/bracing. Examples of shielding include trench boxes and sliding trench shields. Shields are intended primarily to protect workers from cave-ins and do not provide “positive” support of trench sidewalls. As a result, a significant amount of sloughing can occur outside of the trench box, resulting in increased surface disturbance. Examples of shoring/bracing include jacked or braced shores, and soldier pile, sheet pile, or similar shoring walls installed in front of a pre-excavated slope. Jacked or braced shores can utilize wood or aluminum sheeting and be supported with hydraulic, pneumatic, or screw jacks inserted against the sheeting and expanded to provide “positive” support of trench sidewalls. 4.3 DEMOLITION Demolition will include removal of existing asphalt pavement, potentially concrete sidewalks, curbs, and aboveground or underground utilities. During demolition activities, all excavations for demolished utility vaults, utility lines, or other purposes should be backfilled with compacted structural fill, as recommended herein. Existing pavement sections will need to be removed at the start of the planned utility excavations. While these sections were not encountered in borings for this study, the contractor should be prepared to remove a variety of pavement materials including layers / combinations of Hot Mix Asphalt pavement, Portland Cement Concrete pavement, and brick. Pavement sections we encountered generally consisted of 2 to 4 inches of asphalt concrete over aggregate base. Other borings for prior studies in the downtown Renton area encountered asphalt overlying concrete sections up to 8 inches thick and asphalt overlying brick pavement. Neat saw cuts should be required for the margins of all areas of pavement removal, and the extent of pavement removal should account for the planned construction activity, as well as the location of saw cut joints with respect to traffic lanes and wheel paths as outlined in City Standards. The allowed locations for pavement joints may be revised if a mill and overlay will be used to reduce cold joints and avoid locating surface joints in wheel paths. 20212729.001A/SEA21R130976 Page 16 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com Excavations should be supported such that sloughing or undermining of soils supporting pavements or other infrastructure to remain does not occur. If undermining, settlement, or other loss of support occurs it will be necessary to remove additional pavement. This should be done at no cost to the City and with revised saw cut joints in locations determined by a representative of the City. During the course of our field exploration we encountered a number of utilities in the vicinity of our borings, some of which were not marked by our public located request but were instead identified by our private locating subcontractor and may be abandoned. Prior reports also identified unmarked utilities encountered in potholes at 3 to 4 feet bgs, which included a white 3-inch diameter PVC pipe and a rectangular concrete corridor (potential utility duct) on South 2nd Street. Utilities that are to be replaced and are within the excavation area should be removed from the excavation area prior to the installation of new utilities. If required, utility duct demolition and cut off should be accomplished in a manner that prevents damage to the remaining structures and the ends should be sealed with concrete to prevent soil and water from entering the duct. If the duct must be breached to accommodate installation of other utilities, the breach should be sealed with a concrete mass poured into the duct or reinforced concrete slabs/walls. Concrete seals should be designed for a vertical earth pressure equivalent to that generated by a fluid with a unit weight of 125 pounds per cubic foot (pcf) and a lateral earth pressure of 65 pcf. Alternatively, ducts could be backfilled with Controlled Density Fill (CDF) also known as Controlled Low Strength Material (CLSM) provided the contractor is able to deliver the material in a manner that completely fills voids in the duct. CDF should conform to the requirements of Section 2-09.3(1)E Backfilling of the WSDOT Standard Specifications. 4.4 PAVEMENTS 4.4.1 Pavement Repairs / Restoration We understand the City has determined that pavements impacted by utility work will be repaired in accordance with the City of Renton 2018 Trench Restoration and Street Overlay Requirements. In our opinion these are appropriate requirements for the project. Saw cuts and/or grinding should extend a minimum of 1 foot beyond the trench edges and overlays in grinding areas should be a minimum of 2 inches thick. Other factors such as patch orientation, minimum patch widths, and proximity to travel lanes must also be accounted for in determining final repair extents in accordance with City requirements. 20212729.001A/SEA21R130976 Page 17 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com In addition to accounting for the edges of trenches, final patching requirements should encompass and extend 1 foot beyond any additional areas affected by soil movement, settlement, or pavement damage. Additional pavement repairs that are required due to soil movement should be performed at no cost to the City. At the discretion of the engineer, a full lane-width or full street-width overlay may be required. We do not recommend performing a grind and overlay in areas where the existing asphalt is less than 4 inches thick as it becomes difficult to avoid damaging the remaining pavement with construction traffic and variations in grade and pavement thickness can inadvertently result in the milling process damaging or completely removing the pavement section. 4.4.2 New Pavement Sections We understand City of Renton standard sections will be used. Based on our review of the provided standard pavement details, the planned replacement section is a minimum of 6 inches of ½” PG 64-22 Hot Mix Asphalt overlying a minimum of 6 inches of crushed surfacing. This seems reasonable relative to the thicknesses of the existing pavement sections, which generally appear to be performing adequately. Given the variability of the existing pavement section thicknesses and materials, using a standard section for replacement in areas to be removed is recommended over requiring the contractor to match the existing sections encountered as construction progresses. 4.4.3 Pavement and Aggregate Materials and Workmanship Hot Mix Asphalt should conform to requirements of Section 5-04 of the WSDOT Standard Specifications. Aggregate base should conform to Section 9-03.9(3) Crushed Surfacing of the WSDOT Standard Specifications and be compacted to at least 95 percent of the Modified Proctor maximum dry density as determined by ASTM D1557 / AASHTO T180. 4.5 EARTHWORK 4.5.1 Trench and Manhole Subgrades Excavation for trenches and manholes should be done in a manner to minimize disturbance of subgrade soils that will remain in place. Where subgrade soils for manholes consist of 20212729.001A/SEA21R130976 Page 18 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com predominantly granular material, it may be appropriate to compact soils with a plate compactor, jumping jack, or tamping of the excavator bucket to firm up subgrades. Disturbance of soils with high fines contents may require over-excavation and replacement with material conforming to Section 9-03.9(3) Crushed Surfacing of the WSDOT Standards, or other approved material. Utility trenches, particularly in areas below the static water table, may encounter soft subgrades. In many areas pipe bedding will be adequate to stabilize subgrade. Where excessively soft trench subgrade soils are encountered, a geotextile fabric conforming to the requirements of Section 9-33.2(1) Construction Geotextile for Soil Stabilization of the WSDOT Standard should be placed over the subgrade and a 1-foot thick layer 2-4 inch quarry spalls or material conforming to Section 9-03.9(3) Crushed Surfacing of the WSDOT Standards should be placed over the geotextile. In areas with very soft and weak subgrades it may be appropriate to mix the contents of a bulk sack of dry cement into the subgrade and allow it to begin to cure before placing geotextile fabric and rock. Edges of the fabric should overlap a minimum of 18 inches and the fabric should be placed flat over the subgrade with no excessive wrinkles or folds. The contractor should be prepared to utilize geotextile fabric at the direction of the geotechnical engineer. We recommend the contract documents include unit prices for furnishing and installation of geotextile stabilization fabric. 4.5.2 Weather Considerations During wet weather and in areas where the exposed subgrade may consist of moisture-sensitive soils (soils containing approximately more than 10 percent fines based on the fraction passing the ¾-inch sieve), the contractor should take measures to protect subgrade excavations once the geotechnical engineer has approved them. These measures could include, but are not limited to, placing a layer of crushed surfacing over the subgrade and/or keeping construction traffic off the subgrade. If additional over-excavation and material replacement is required because the subgrade was not protected, the cost of such additional work should be borne by the contractor. After a rainfall, construction equipment travel on the exposed site subgrade should be minimized until the soils have been allowed to dry sufficiently. Otherwise, traffic activity on the wetted subgrade will degrade the exposed materials and result in additional excavation of the disturbed materials. 20212729.001A/SEA21R130976 Page 19 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 4.5.3 Structural Fill Materials All fill placed below pavements, sidewalks, or structures such as catch basins should be considered structural fill. The on-site fill and native soils that will be excavated from utility trenches will generally be unsuitable for re-use as structural fill because they contain a high fines content and will be over their optimum water content and not readily compactable. In addition, the project site may not have room for temporary stockpiling of trench materials near the work areas. Therefore, we recommend the contract documents include a provision for import of structural fill and export of unsuitable soils with unit pricing. The suitability of on-site soils for re-use can be evaluated on a case-by-case basis during utility installation by a representative of Kleinfelder, if desired. Structural fill materials and bedding should conform to WSDOT/APWA standards, as well as City of Renton details. Pipe zone backfill placed within 6 inches of pipes should conform to the requirements of Section 9-03.12(3) Gravel Backfill for Pipe Zone Bedding of the WSDOT Standards, or manufacturer requirements. Imported structural fill should consist of material conforming to the requirements of Section 9-03.14(1) Gravel Borrow of the WSDOT Standards. Material placed within the pavement section should conform to the corresponding pavement section requirements. Materials should be imported to the site and protected or maintained so that they are not more than 3 percent over their optimum moisture content at the time of placement and compaction. The contractor should provide submittals as required by the contract documents. Once approved for use, the contractor should submit samples of import materials to the geotechnical engineer for evaluation and testing prior to use. The samples should be submitted at least 4 days prior to their use and sufficiently in advance of the work to allow the contractor to identify alternative sources if the material proves unsatisfactory. In some instances where multiple utilities cross in a small area and backfill cannot be readily worked and compacted around the utilities, it may be advantageous to backfill with CDF. CDF should conform to the requirements of Section 2-09.3(1)E Backfilling of the WSDOT Standard Specifications and we recommend the contract documents include a unit price for CDF backfill. Use of CDF should only be approved on a case-by-case basis by the engineer. 20212729.001A/SEA21R130976 Page 20 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 4.5.4 Structural Fill Placement and Compaction We understand that the WSDOT/APWA Standard Specifications will be used for this project. We recommend that laboratory compaction testing be performed based on the modified Proctor test method (ASTM D1557 / AASHTO T180) as opposed to the standard Proctor test method (ASTM D698 / AASHTO T99). The higher compaction standard of the modified Proctor is appropriate considering that extensive trenching will be performed through existing road sections and pavements that will not be totally reconstructed. Using the higher density standard will reduce the potential for differential settlement. Prior to placement and compaction, structural fill should be moisture conditioned to within 3 percent of the optimum moisture content. Fill should be placed in loose lifts with a maximum thickness of 8 inches and should be compacted to the following minimum relative compaction based on the modified Proctor test method (ASTM D1557): • Catch Basin/Structure/Manhole Foundations: 95 Percent • Pavement/Sidewalk Subgrades: 95 Percent • Trench Backfill: 95 Percent • Pipe Zone Bedding: 90 Percent (within 6 inches of pipe) In addition to meeting the above density requirements, all fill should be firm and unyielding when loaded. We recommend all structural fill compaction be observed and tested by a representative of the geotechnical engineer. 4.5.5 Construction Dewatering Based on the anticipated pipeline and treatment facility depths, dewatering is not anticipated with the exception of the potential outfall replacement, if included in the project. However, due to the potential for isolated areas of perched water and minor seepage, the contractor should be prepared to address nuisance water by use of sumps and pumps. Where encountered, the groundwater level should be maintained two feet below the excavation bottom until at least two feet of backfill has been placed, and the groundwater should not be allowed to rise any higher than two feet below the level of excavation backfill during the backfill operation. Excessive lowering of the groundwater table during construction, or on a long-term basis, can induce settlement of the observed soils within the project area and could result in damage to 20212729.001A/SEA21R130976 Page 21 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com structures and utilities in the area if not properly managed. In general, we do not recommend lowering groundwater by more than 10 feet of drawdown. However, it is the contractor’s responsibility to evaluate appropriate dewatering methods and drawdown levels along the alignment to prevent damaging settlements and/or migration of groundwater contaminants. 4.6 ENVIRONMENTAL FIELD SCREENING All soil samples were field screened for organic vapors using a field calibrated photoionization detector (PID) and monitored for evidence of petroleum staining and/or odors. No indications of contamination or elevated PID readings were noted in any of the borings, therefore no soil samples were submitted for laboratory analysis of petroleum hydrocarbons or volatile organic compounds. The drummed soil cuttings were deemed “clean” and disposed of off-site as clean material. 20212729.001A/SEA21R130976 Page 22 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 5 LIMITATIONS ___________________________________________________________________________________ This geotechnical study has been prepared for the exclusive use of BHC Consultants and the City of Renton for specific application to the proposed Burnett Ave South and Williams Ave South Water Quality Improvement Project. The findings, conclusions and recommendations presented in this report were prepared in accordance with generally accepted geotechnical engineering practice. No other warranty, express or implied, is made. The scope of services was limited to a background data review and the field exploration described in Section 1. It should be recognized that definition and evaluation of subsurface conditions are difficult. Judgments leading to conclusions and recommendations are generally made with incomplete knowledge of the subsurface conditions present due to the limitations of data from field studies. The conclusions of this assessment are based on our field exploration and laboratory testing programs, and engineering analysis. Kleinfelder offers various levels of investigative and engineering services to suit the varying needs of different clients. Although risk can never be eliminated, more detailed and extensive studies yield more information, which may help understand and manage the level of risk. Since detailed study and analysis involves greater expense, our clients participate in determining levels of service, which provide information for their purposes at acceptable levels of risk. The client and key members of the design team should discuss the issues covered in this report with Kleinfelder, so that the issues are understood and applied in a manner consistent with the owner’s budget, tolerance of risk and expectations for future performance and maintenance. Recommendations contained in this report are based on our field observations and subsurface explorations, limited laboratory tests, and our present knowledge of the proposed construction. It is possible that soil or groundwater conditions could vary between or beyond the points explored. If soil or groundwater conditions are encountered during construction that differ from those described herein, the client is responsible for ensuring that Kleinfelder is notified immediately so that we may reevaluate the recommendations of this report. If the scope of the proposed construction, including the estimated Traffic Index or locations of the improvements, changes from that described in this report, the conclusions and recommendations contained in this report are not considered valid until the changes are reviewed, and the conclusions of this report are modified or approved in writing, by Kleinfelder. 20212729.001A/SEA21R130976 Page 23 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com Kleinfelder cannot be responsible for interpretation by others of this report or the conditions encountered in the field. Kleinfelder must be retained so that all geotechnical aspects of construction will be monitored by a representative from Kleinfelder. These services provide Kleinfelder the opportunity to observe the actual soil and groundwater conditions encountered during construction and to evaluate the applicability of the recommendations presented in this report to the site conditions. If Kleinfelder is not retained to provide these services, we will cease to be the engineer of record for this project and will assume no responsibility for any potential claim during or after construction on this project. If changed site conditions affect the recommendations presented herein, Kleinfelder must also be retained to perform a supplemental evaluation and to issue a revision to our original report. This report, and any future addenda or reports regarding this site, may be made available to bidders to supply them with only the data contained in the report regarding subsurface conditions and laboratory test results at the point and time noted. Bidders may not rely on interpretations, opinion, recommendations, or conclusions contained in the report. Because of the limited nature of any subsurface study, the contractor may encounter conditions during construction which differ from those presented in this report. In such event, the contractor should promptly notify the owner so that Kleinfelder’s geotechnical engineer can be contacted to evaluate those conditions. We recommend the contractor describe the nature and extent of the differing conditions in writing and that the construction contract include provisions for dealing with differing conditions. Contingency funds should be reserved for potential problems during construction. This report may be used only by the client and only for the purposes stated, within a reasonable time from its issuance, but in no event later than two years from the date of the report. Land use, site conditions (both on site and off site) or other factors may change over time, and additional work may be required with the passage of time. Any party, other than the client who wishes to use this report shall notify Kleinfelder of such intended use. Based on the intended use of this report and the nature of the new project, Kleinfelder may require that additional work be performed and that an updated report be issued. Non-compliance with any of these requirements by the client or anyone else will release Kleinfelder from any liability resulting from the use of this report by any unauthorized party and the client agrees to defend, indemnify, and hold harmless Kleinfelder from any claims or liability associated with such unauthorized use or non-compliance. 20212729.001A/SEA21R130976 Page 24 of 24 September 27, 2021 © 2021 Kleinfelder www.kleinfelder.com 6 REFERENCES ___________________________________________________________________________________ City of Renton Department of Community and Economic Development Trench Restoration and Street Overlay Requirements, Renton, Washington, February 16, 2018 Earth Solutions NW LLC. (2014). Geotechnical Evaluation, Renton Heritage Apartments, South 2nd Street and Main Ave., Renton, Washington, September 11, 2014 GeoDesign, Inc. (2016). Report of Geotechnical Engineering Services, City of Renton, Downtown Circulation Project – Phase 1, Main Avenue South and Bronson Way South, Renton Washington, January 14, 2016 Geotech Consultants, (2007). Inc., Geotechnical Engineering Study, Proposed Mixed-Use Building, 207-219 Main Avenue South, Renton, Washington, July 18, 2007 Jennifer Ott, (2012). Due to construction of Lake Washington Ship Canal, Lake Washington is lowered 9 feet beginning on August 28, 1916, and the Black River disappears, October 1, 2012 Kleinfelder, Inc. (2020) Geotechnical and Environmental Report Downtown Utility Improvements Project Renton, Washington Kleinfelder Project # 20181376.003A March 31, 2020 Soil & Environmental Engineers, (2011). Inc. Report of Geotechnical investigation, Lake Ave S. Storm System Project, Renton, Washington, S&EE Job No. 912, February 10, 2011 King County Flood Control District, (2010). Map 11-5 Liquefaction Susceptibility, May 2010 City of Renton Maps and GIS Data, Accessed December 7, 2020 Washington Department of Natural Recourses Interactive Geologic Maps, Accessed February 8, 2021 WSDOT (2020). Standard Specifications for Road, Bridge, and Municipal Construction, Publication Number M41-10 FORMERCEDAR R IVER FORME RBLACK R IV ER The information included on this graphic representation has been compiled from a variety of sources and is subject to change without notice. Kleinfelder makes no representations or warranties, express or implied, as to accuracy, completeness, timeliness, or rights to the use of such information. This document is not intended for use as a land survey product nor is it designed or intended as a construction design document. The use or misuse of the information contained on this graphic representation is at the sole risk of the party using or misusing the information.CAD FILE: U:\Projects\CADD\CADD 2021\20212729\20212729_Burnett-Williams.dwgPLOTTED: 2/19/2021 8:35 AM BY: dean fahrneyDRAWN BY: PROJECT NO. CHECKED BY: REVISED: DATE: FIGURESITE VICINITY MAP20212729 DMF WR 02/2021 - 1 CITY OF RENTON DOWNTOWN UTILITY IMPROVEMENTS PROJECT RENTON, WASHINGTON 02,000 2,0001,000 APPROXIMATE SCALE (feet) SOURCE:U.S.G.S. 7.5' Topographic series, Renton, Washington Quadrangle 2017. SITE VICINITY MAP BURNETT AVE SOUTH AND WILLIAMS AVE SOUTH WATER QUALITY RETROFIT PROJECT RENTON, WASHINGTON EXPLANATION APPROXIMATE LOCATION OF FORMER BLACK AND CEDAR RIVERS FOR M E R C E D A R R I V E R FORMER BLACK RIVER N SITE © 2021 Microsoft Corporation © 2021 Maxar ©CNES (2021) Distribution Airbus DS FORMER CEDAR RIVER MW-5 KB-4 KB-2 KB-3 KB-4 BURNETT AVENUE S WILLIAMS AVENUE S S 2ND STREETS TOBIN STREETKB-1 CAD FILE: U:\Projects\CADD\CADD 2021\20212729\20212729_Burnett-Williams.dwg LAYOUT: Explor-2PLOTTED: 2/19/2021 8:37 AM BY: dean fahrneyFIGURE DRAWN BY DATE: PROJECT: CHECKED BY REVISED: SITE AND EXPLORATION PLAN CITY OF RENTON DOWNTOWN UTILITY IMPROVEMENTS PROJECT RENTON, WASHINGTON 20212729 DMF WR 02/2021 - 2The information included on this graphic representation has been compiled from a variety of sources and is subject to change without notice. Kleinfelder makes no representations or warranties, express or implied, as to accuracy, completeness, timeliness, or rights to the use of such information. This document is not intended for use as a land survey product nor is it designed or intended as a construction design document. The use or misuse of the information contained on this graphic representation is at the sole risk of the party using or misusing the information.N0100 10050 APPROXIMATE SCALE (feet) SITE AND EXPLORATION PLAN BURNETT AVE SOUTH AND WILLIAMS AVE SOUTH WATER QUALITY RETROFIT PROJECT RENTON, WASHINGTON EXPLANATION APPROXIMATE EXPLORATION LOCATIONKB-4 EXPLORATION LOCATION COMPLETED FOR PRIOR PROJECT (DUIP)KB-4 PROJECT BOUNDARY APPROXIMATE LOCATION OF FORMER CEDAR RIVER APPENDIX A BORING LOGS ___________________________________________________________________________________ A-1 APPENDIXGRAPHICS KEY Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, Washington The report and graphics key are an integral part of these logs. All data and interpretations in this log are subject to the explanations and limitations stated in the report. Lines separating strata on the logs represent approximate boundaries only. Actual transitions may be gradual or differ from those shown. No warranty is provided as to the continuity of soil or rock conditions between individual sample locations. Logs represent general soil or rock conditions observed at the point of exploration on the date indicated. In general, Unified Soil Classification System designations presented on the logs were based on visual classification in the field and were modified where appropriate based on gradation and index property testing. Fine grained soils that plot within the hatched area on the Plasticity Chart, and coarse grained soils with between 5% and 12% passing the No. 200 sieve require dual USCS symbols, ie., GW-GM, GP-GM, GW-GC, GP-GC, GC-GM, SW-SM, SP-SM, SW-SC, SP-SC, SC-SM. If sampler is not able to be driven at least 6 inches then 50/X indicates number of blows required to drive the identified sampler X inches with a 140 pound hammer falling 30 inches. ABBREVIATIONS WOH - Weight of Hammer WOR - Weight of Rod WELL-GRADED GRAVELS, GRAVEL-SAND MIXTURES WITH LITTLE FINES WELL-GRADED GRAVELS, GRAVEL-SAND MIXTURES WITH LITTLE CLAY FINES POORLY GRADED GRAVELS, GRAVEL-SAND MIXTURES WITH LITTLE FINES POORLY GRADED GRAVELS, GRAVEL-SAND MIXTURES WITH LITTLE CLAY FINES SILTY GRAVELS, GRAVEL-SILT-SAND MIXTURES CLAYEY GRAVELS, GRAVEL-SAND-CLAY-SILT MIXTURES WELL-GRADED SANDS, SAND-GRAVEL MIXTURES WITH LITTLE CLAY FINES POORLY GRADED SANDS, SAND-GRAVEL MIXTURES WITH LITTLE CLAY FINES SW SW-SC POORLY GRADED SANDS, SAND-GRAVEL MIXTURES WITH LITTLE FINES Cu 4 and/ or 1 Cc 3> > INORGANIC SILTS AND VERY FINE SANDS, SILTY OR CLAYEY FINE SANDS, SILTS WITH SLIGHT PLASTICITY ORGANIC CLAYS & ORGANIC SILTS OF MEDIUM-TO-HIGH PLASTICITY INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE SAND OR SILT INORGANIC CLAYS-SILTS OF LOW PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS _ SILTY SANDS, SAND-GRAVEL-SILT MIXTURES CLAYEY SANDS, SAND-GRAVEL-CLAY MIXTURES SW-SM CLAYEY SANDS, SAND-SILT-CLAY MIXTURES CL CL-ML > < < SANDS WITH 5% TO 12% FINES SANDS WITH > 12% FINES WELL-GRADED SANDS, SAND-GRAVEL MIXTURES WITH LITTLE FINES Cu 4 and/ or 1 Cc 3> CLEAN GRAVEL WITH <5% FINES GRAVELS WITH 5% TO 12% FINES OL CH CLAYEY GRAVELS, GRAVEL-SAND-CLAY MIXTURES FINE GRAINED SOILS(Half or more of material issmaller thanthe #200 sieve)GRAVELS WITH > 12% FINES > Cu 4 and 1 Cc 3 >_ _ STANDARD PENETRATION SPLIT SPOON SAMPLER (2 in. (50.8 mm.) outer diameter and 1-3/8 in. (34.9 mm.) inner diameter) _ GM GC GW GP GW-GM GW-GC _ _ _ INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS < SAMPLE/SAMPLER TYPE GRAPHICS > < < > CLEAN SANDS WITH <5% FINESGRAVELS (More than half of coarse fraction is larger than the #4 sieve)Cu 6 and/ or 1 Cc 3 Cu 6 and/ or 1 Cc 3 > Cu 6 and 1 Cc 3 SC-SM Cu 4 and 1 Cc 3 <_ ORGANIC SILTS & ORGANIC SILTY CLAYS OF LOW PLASTICITY SILTS AND CLAYS (Liquid Limit less than 50) WELL-GRADED SANDS, SAND-GRAVEL MIXTURES WITH LITTLE OR NO FINES POORLY GRADED SANDS, SAND-GRAVEL MIXTURES WITH LITTLE OR NO FINES MH OH ML GC-GM COARSE GRAINED SOILS (More than half of material is larger than the #200 sieve)UNIFIED SOIL CLASSIFICATION SYSTEM (ASTM D 2487) < Cu 6 and 1 Cc 3 GP-GM GP-GC _ _ _< > < < > SP SP-SM SP-SC SM SC <_< > WELL-GRADED GRAVELS, GRAVEL-SAND MIXTURES WITH LITTLE OR NO FINES POORLY GRADED GRAVELS, GRAVEL-SAND MIXTURES WITH LITTLE OR NO FINES SILTS AND CLAYS (Liquid Limit 50 or greater)SANDS (Half or more of coarse fraction is smaller than the #4 sieve)NOTE: USE MATERIAL DESCRIPTION ON THE LOG TO DEFINE A GRAPHIC THAT MAY NOT BE PROVIDED ON THIS LEGEND. GROUND WATER GRAPHICS OBSERVED SEEPAGE WATER LEVEL (level after exploration completion) WATER LEVEL (level where first observed) WATER LEVEL (additional levels after exploration) NOTES gINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [__KLF_GEO-LEG1 (GRAPHICS KEY) WITH USCS]PLOTTED: 02/18/2021 11:10 AM BY: WRossoDATE: CHECKED BY: DRAWN BY: 20212729.001A PROJECT NO.: A-2 SOIL DESCRIPTION KEY APPENDIX CALIFORNIA SAMPLER (# blows/ft) MODIFIED CA SAMPLER (# blows/ft) SPT-N60(# blows/ft) Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, Washington DESCRIPTION FIELD TEST PP < 0.25 Medium Stiff 0.25 PP <0.5 30 - 50 10 - 30 4 - 10 <4 >60 35 - 60 12 - 35 5 - 12 <4 >70 40 - 70 15 - 40 5 - 15 CONSISTENCY <2 Moist DESCRIPTION Strongly FIELD TEST >30 Very Soft PI NP Either the LL or the PI (or both) may be used to describe the soil plasticity. The ranges of numbers shown here do not imply that the LL ranges correlate with the PI ranges for all soils. DESCRIPTION Damp but no visible water Boulders Cobbles coarse fine Gravel Sand Fines GRAIN SIZE >12 in. (304.8 mm.) 3 - 12 in. (76.2 - 304.8 mm.) Fist-sized to basketball-sized 3/4 -3 in. (19 - 76.2 mm.) Thumb-sized to fist-sized 0.19 - 0.75 in. (4.8 - 19 mm.) Pea-sized to thumb-sized 0.079 - 0.19 in. (2 - 4.9 mm.)#10 - #4 0.017 - 0.079 in. (0.43 - 2 mm.) #200 - #40 coarse fine medium SIEVE SIZE APPROXIMATE SIZE Larger than basketball-sized>12 in. (304.8 mm.) 3 - 12 in. (76.2 - 304.8 mm.) 3/4 -3 in. (19 - 76.2 mm.) #4 - 3/4 in. (#4 - 19 mm.) Rock salt-sized to pea-sized #40 - #10 Sugar-sized to rock salt-sized 0.0029 - 0.017 in. (0.07 - 0.43 mm.) Flour-sized to sugar-sized Passing #200 <0.0029 in. (<0.07 mm.) Flour-sized and smaller DESCRIPTION Secondary Constituent is Fine Grained Secondary Constituent is Coarse Grained SPT - N60(# blows / ft) Soft Stiff Very Stiff Hard 2 - 4 4 - 8 8 - 15 15 - 30 Weakly Crumbles or breaks with handling or slight finger pressure Crumbles or breaks with considerable finger pressure UNCONFINED COMPRESSIVE STRENGTH (Qu)(psf) VISUAL / MANUAL CRITERIA <500 0.5 PP <1 1 PP <2 2 PP <4 4 PP >8000 4000 - 8000 500 - 1000 1000 - 2000 2000 - 4000 Dry Wet Visible free water, usually soil is below water table Thumb will penetrate more than 1 inch (25 mm). Extrudes between fingers when squeezed. Thumb will penetrate soil about 1 inch (25 mm). Remolded by light finger pressure. Thumb will penetrate soil about 1/4 inch (6 mm). Remolded by strong finger pressure. Can be imprinted with considerable pressure from thumb. Thumb will not indent soil but readily indented with thumbnail. Thumbnail will not indent soil. DESCRIPTION Alternating layers of varying material or color with the layer less than 1/4-in. thick, note thickness. 15 - 25 > 25 FIELD TEST Absence of moisture, dusty, dry to the touch Moderately Will not crumble or break with finger pressure Pocket Pen (tsf) Term of Use <5% With Modifier 5 to <15% 15% Trace <15% 15 to <30% 30% AMOUNT Fissured Slickensided Blocky Lensed CRITERIA Stratified Laminated Fracture planes appear polished or glossy, sometimes striated. Alternating layers of varying material or color with layers at least 1/4-in. thick, note thickness. Breaks along definite planes of fracture with little resistance to fracturing. Cohesive soil that can be broken down into small angular lumps which resist further breakdown. Inclusion of small pockets of different soils, such as small lenses of sand scattered through a mass of clay; note thickness. None Weak Strong No visible reaction RELATIVE DENSITY (%) APPARENT DENSITY Some reaction, with bubbles forming slowly Violent reaction, with bubbles forming immediately 85 - 100 65 - 85 35 - 65 15 - 35 <5 0 - 15 Very Dense Dense Medium Dense >50 Loose Very Loose FROM TERZAGHI AND PECK, 1948 DESCRIPTION Non-Plastic NP LL Low < 30 Medium 30 - 50 High > 50 LL is from Casagrande, 1948. PI is from Holtz , 1959. < 15 Rounded Subrounded Particles have nearly plane sides but have well-rounded corners and edges. Angular Particles have sharp edges and relatively plane sides with unpolished surfaces. Subangular Particles have smoothly curved sides and no edges. Particles are similar to angular description but have rounded edges. DESCRIPTION CRITERIA MOISTURE CONTENT CONSISTENCY - FINE-GRAINED SOIL REACTION WITH HYDROCHLORIC ACID STRUCTURE SECONDARY CONSTITUENT CEMENTATION APPARENT / RELATIVE DENSITY - COARSE-GRAINED SOIL GRAIN SIZE PLASTICITY ANGULARITY gINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [_KLF_GEO-LEG 2 (SOIL DESC KEY)]PLOTTED: 02/18/2021 11:11 AM BY: WRossoDATE: CHECKED BY: DRAWN BY: 20212729.001A PROJECT NO.: 97 91 31 1.4 ASPHALT: 4 inch asphalt section FILL GRAVEL with Silt and Sand (GP-GM): brownish gray, moist, fine to coarse rounded to subangular gravel, fine to coarse sand Sandy SILT (ML): brownish gray, moist, fine sand, low plasticity small roots observed in sidewall of exploration Poorly Graded GRAVEL with Silt and Sand (GP-GM): brownish gray, moist, dense, fine to coarse rounded to subangular gravel, fine to coarse sand Silty SAND(SM): brownish gray, moist, very loose, fine sand ALLUVIUM Poorly Graded SANDwith Silt and Gravel (SP-SM): gray, wet, very loose to medium dense, fine to medium sand, fine to coarse rounded gravel buried reddish yellow timber/wood buried timber/wood continues trace organics (bark) The boring was terminated at approximately 31.5 ft. below ground surface. The boring was backfilled with auger cuttings, bentonite and patched at surface on February 04, 2020. 7" 5" 12" 9" 14" 10" SM SP 7.3 33.5 22.3 28.3 26.8 23.4 BC=12 23 16 BC=1 1 1 BC=3 3 1 BC=2 1 1 BC=4 10 15 BC=9 12 15 39 Due to the proximity of a high pressure gas line this exploration was cleared to approximately 7.5 feet bgs using a vac truck and air knife. Soils within the cleared area were identified by examining the exploration's sidewall and cuttings. PID= 1.2 PID= 1.8 PID= 1.8 PID= 4.1 PID= 3.3 PID= 1.8 13 Groundwater was observed at approximately 15 ft. below ground surface during drilling. GENERAL NOTES: GROUNDWATER LEVEL INFORMATION: 1 of 1 FIELD EXPLORATION APPENDIX A-3 LABORATORY RESULTS Lithologic Description BORING LOG KB-1 PAGE: BORING LOG KB-1 Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%) Surface Condition: Asphalt WGS84 Holocene Drilling, Inc.Drilling Company: Drilling Method: Drilling Equipment: Light rain, 40's Exploration Diameter: Hammer Type - Drop:140 lb. Auto - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: Diedrich D-50 8 in. O.D. MAE Hollow Stem AugerPlunge:-90 degrees RJ 2/04/2020 Depth (feet)5 10 15 20 25 30 Graphical LogRecovery(NR=No Recovery)USCSSymbolWaterContent (%)Blow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitAdditional Tests/RemarksPlasticity Index(NP=NonPlastic)Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, Washington DRAWN BY: MAE PROJECT NO.: 20212729.001APLOTTED: 02/23/2021 03:21 PM BY: WRossogINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [__KLF_BORING/TEST PIT SOIL LOG]DATE: 2/22/2021 CHECKED BY: WRRSample Type 100 52 77 4.1 ASPHALT: 3 inch asphalt section ASPHALT BASE COURSE Poorly Graded GRAVEL with Silt and Sand (GP-GM): light brownish gray, moist, loose, 3 inch base course FILL Sandy SILT with Gravel (ML): dark brown, moist, soft, fine to coarse sand, fine subrounded to subangular gravel, 2 inch piece of asphalt in sample SILT with Sand (ML): brownish gray, moist, soft, fine sand, low to moderate plasticity, orange mottling trace organics (small piece of bark, rootlets) orange mottling ALLUVIUM Poorly Graded GRAVEL with Sand (GP): brown, wet, medium dense, fine to coarse rounded to subangular gravel, fine to coarse sand Poorly Graded SANDwith Silt and Gravel (SP-SM): brownish gray, wet, dense, fine to coarse sand, with fine to coarse subrounded to subangular gravel The boring was terminated at approximately 21.5 ft. below ground surface. The boring was backfilled with auger cuttings, bentonite and patched at surface on February 04, 2020. 2" 18" 18" 10" 13" 8" ML GP 3.7 32.1 28.9 30.3 11.8 11.2 BC=3 1 2 BC=2 1 2 BC=2 2 1 BC=2 1 2 BC=13 12 14 BC=17 13 23 33 PID= 2.8 PID= 2.3 PID= 2.4 PID= 3.5 PID= 1.8 PID= 2.7 5 Groundwater was observed at approximately 15 ft. below ground surface during drilling. GENERAL NOTES: GROUNDWATER LEVEL INFORMATION: 1 of 1 FIELD EXPLORATION APPENDIX A-4 LABORATORY RESULTS Lithologic Description BORING LOG KB-2 PAGE: BORING LOG KB-2 Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%) Surface Condition: Asphalt WGS84 Holocene Drilling, Inc.Drilling Company: Drilling Method: Drilling Equipment: Light rain, 40's Exploration Diameter: Hammer Type - Drop:140 lb. Auto - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: Diedrich D-50 8 in. O.D. MAE Hollow Stem AugerPlunge:-90 degrees RJ 2/04/2020 Depth (feet)5 10 15 20 25 30 Graphical LogRecovery(NR=No Recovery)USCSSymbolWaterContent (%)Blow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitAdditional Tests/RemarksPlasticity Index(NP=NonPlastic)Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, Washington DRAWN BY: MAE PROJECT NO.: 20212729.001APLOTTED: 02/23/2021 03:21 PM BY: WRossogINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [__KLF_BORING/TEST PIT SOIL LOG]DATE: 2/22/2021 CHECKED BY: WRRSample Type 33 43 74 2.9 3.5 2.0 ASPHALT: 4 inch asphalt section ASPHALT BASE COURSE Poorly Graded GRAVEL with Silt and Sand (GP-GM): brownish gray, moist, loose, 3 inch base course FILL Sandy SILT (ML): yellowish brown, moist, medium stiff, fine sand ALLUVIUM Well-Graded GRAVEL with Sand (GW): yellowish brown, moist, medium dense to dense, fine to coarse sand, fine to coarse rounded to subangular gravel, trace silt becomes wet Poorly Graded SANDwith Gravel (SP): brownish gray, moist, medium dense, coarse sand, fine rounded to subangular gravel The boring was terminated at approximately 21.5 ft. below ground surface. The boring was backfilled with auger cuttings, bentonite and patched at surface on February 04, 2020. 2" 4" 3" 7" 12" 7" GW GW SP 20.5 8.3 8.2 3.0 8.1 14.8 BC=5 2 2 BC=3 2 2 BC=11 9 13 BC=9 12 11 BC=14 16 18 BC=9 5 6 PID= 1.4 PID= 1.1 PID= 1.9 PID= 0.6 PID= 0.7 PID= 1.3 Groundwater was observed at approximately 15 ft. below ground surface during drilling. GENERAL NOTES: GROUNDWATER LEVEL INFORMATION: 1 of 1 FIELD EXPLORATION APPENDIX A-5 LABORATORY RESULTS Lithologic Description BORING LOG KB-3 PAGE: BORING LOG KB-3 Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%) Surface Condition: Asphalt WGS84 Holocene Drilling, Inc.Drilling Company: Drilling Method: Drilling Equipment: Light rain, 40's Exploration Diameter: Hammer Type - Drop:140 lb. Auto - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: Diedrich D-50 8 in. O.D. MAE Hollow Stem AugerPlunge:-90 degrees RJ 2/04/2020 Depth (feet)5 10 15 20 25 30 Graphical LogRecovery(NR=No Recovery)USCSSymbolWaterContent (%)Blow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitAdditional Tests/RemarksPlasticity Index(NP=NonPlastic)Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, Washington DRAWN BY: MAE PROJECT NO.: 20212729.001APLOTTED: 02/23/2021 03:22 PM BY: WRossogINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [__KLF_BORING/TEST PIT SOIL LOG]DATE: 2/22/2021 CHECKED BY: WRRSample Type 46 20 34 5.7 1.1 0.6 ASPHALT: 2 inch asphalt section ASPHALT BASE COURSE Poorly Graded GRAVEL (GP): light gray, moist, loose, 6 inch base course FILL Poorly Graded GRAVEL with Sand (GP): gray, moist, loose, fine to coarse subangular gravel, medium to coarse sand, trace silt Poorly Graded GRAVEL with Silt and Sand (GP-GM): dark yellowish brown, moist, medium dense to dense, fine to coarse rounded to subrounded gravel, fine to coarse sand silt content increases, moisture content increases near tip of sampler ALLUVIUM Poorly Graded GRAVEL with Sand (GP): dark yellowish brown, wet, medium dense, fine to coarse subrounded to rounded gravel, trace silt Well-Graded GRAVEL with Sand (GW): dark yellowish brown, wet, medium dense, fine to coarse rounded gravel, fine to coarse sand, trace silt The boring was terminated at approximately 21.5 ft. below ground surface. The boring was backfilled with auger cuttings, bentonite and patched at surface on February 04, 2020. 1" 10" 14" 6" 8" 10" GP-GM GP GW 6.2 5.7 5.7 31.2 5.4 5.3 BC=5 3 4 BC=9 8 8 BC=11 18 19 BC=14 18 20 BC=10 9 10 BC=9 9 9 PID= 1.4 PID= 1.6 PID= 1.3 PID= 1.2 PID= 2.8 PID= 2.2 Groundwater was observed at approximately 15 ft. below ground surface during drilling. GENERAL NOTES: GROUNDWATER LEVEL INFORMATION: 1 of 1 FIELD EXPLORATION APPENDIX A-6 LABORATORY RESULTS Lithologic Description BORING LOG KB-4 PAGE: BORING LOG KB-4 Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%) Surface Condition: Asphalt WGS84 Holocene Drilling, Inc.Drilling Company: Drilling Method: Drilling Equipment: Light rain, 40's Exploration Diameter: Hammer Type - Drop:140 lb. Auto - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: Diedrich D-50 8 in. O.D. MAE Hollow Stem AugerPlunge:-90 degrees RJ 2/04/2020 Depth (feet)5 10 15 20 25 30 Graphical LogRecovery(NR=No Recovery)USCSSymbolWaterContent (%)Blow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitAdditional Tests/RemarksPlasticity Index(NP=NonPlastic)Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, Washington DRAWN BY: MAE PROJECT NO.: 20212729.001APLOTTED: 02/23/2021 03:22 PM BY: WRossogINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [__KLF_BORING/TEST PIT SOIL LOG]DATE: 2/22/2021 CHECKED BY: WRRSample Type APPENDIX B GEOTECHNICAL LABORATORY TESTING ___________________________________________________________________________________ 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 3/8 3 1002416 301 2006 10 Sample Description LL PL PI CuCc 20 40BOULDER6 601.5 8 %Clay*D60 D30 D10D100 Passing 3/4" Passing #4 Passing #200 26 NM 28 NM NM 39 NM 33 NM NM 13 NM 5 NM NM NM 0.429 NM 0.724 3.706 NM 0.253 NM 0.265 0.378 10 30 7.5 15 10 97 91 100 52 33 100 100 86 73 25 25 4.75 25 25 NM NM NM NM NM Exploration ID Depth (ft.)PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS medium fine GRAVEL SANDCOBBLEcoarse coarsefine Exploration ID Depth (ft.) 1 SIEVE ANALYSIS SILT 50 HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS 1403 4 Coefficients of Uniformity - Cu = D60 / D10 Coefficients of Curvature - CC = (D30)2 / D60 D10 D60 = Grain diameter at 60% passing D30 = Grain diameter at 30% passing D10 = Grain diameter at 10% passing 10 30 7.5 15 10 KB-1 KB-1 KB-2 KB-2 KB-3 KB-1 KB-1 KB-2 KB-2 KB-3 0.536 0.693 NM 7.115 13.501 SILTY SAND (SM) POORLY GRADED SAND (SP) SILT with SAND (ML) POORLY GRADED GRAVEL with SAND (GP) WELL-GRADED GRAVEL with SAND (GW) NM 1.05 NM 0.28 2.69 NM 2.73 NM 26.84 35.75 TABLE 143/4 1/212 31 1.4 77 4.1 2.9 NM NM NM NM NM CLAY %Silt* *These numbers represent silt-sized and clay-sized content but may not indicate the percentage of the material with the engineering properties of silt or clay. Sieve Analysis and Hydrometer Analysis testing performed in general accordance with ASTM D6913(Sieve Analysis) and ASTM D7928 (Hydrometer Analysis). NP = Nonplastic NM = Not Measured Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, WashingtonPLOTTED: 02/18/2021 11:05 AM BY: WRossogINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [_KLF_SIEVE ANALYSIS]DATE: 2/22/2021 CHECKED BY: WRR DRAWN BY: MAE PROJECT NO.: 20212729.001A 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 3/8 3 1002416 301 2006 10 Sample Description LL PL PI CuCc 20 40BOULDER6 601.5 8 %Clay*D60 D30 D10D100 Passing 3/4" Passing #4 Passing #200 NM NM NM NM NM NM NM NM NM NM NM NM NM NM NM 2.02 0.696 1.189 7.99 3.925 0.349 0.321 0.208 0.488 0.923 15 20 7.5 15 20 43 74 46 20 34 81 84 67 82 50 37.5 37.5 37.5 37.5 NM NM NM NM NM Exploration ID Depth (ft.)PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS medium fine GRAVEL SANDCOBBLEcoarse coarsefine Exploration ID Depth (ft.) 1 SIEVE ANALYSIS SILT 50 HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS 1403 4 Coefficients of Uniformity - Cu = D60 / D10 Coefficients of Curvature - CC = (D30)2 / D60 D10 D60 = Grain diameter at 60% passing D30 = Grain diameter at 30% passing D10 = Grain diameter at 10% passing 15 20 7.5 15 20 KB-3 KB-3 KB-4 KB-4 KB-4 KB-3 KB-3 KB-4 KB-4 KB-4 10.353 2.043 8.993 16.887 10.209 WELL-GRADED GRAVEL with SAND (GW) POORLY GRADED SAND with GRAVEL (SP) POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM) POORLY GRADED GRAVEL with SAND (GP) WELL-GRADED GRAVEL with SAND (GW) 1.13 0.74 0.76 7.75 1.63 29.68 6.37 43.25 34.61 11.06 TABLE 143/4 1/212 3.5 2.0 5.7 1.1 0.6 NM NM NM NM NM CLAY %Silt* *These numbers represent silt-sized and clay-sized content but may not indicate the percentage of the material with the engineering properties of silt or clay. Sieve Analysis and Hydrometer Analysis testing performed in general accordance with ASTM D6913(Sieve Analysis) and ASTM D7928 (Hydrometer Analysis). NP = Nonplastic NM = Not Measured Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, WashingtonPLOTTED: 02/18/2021 11:05 AM BY: WRossogINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [_KLF_SIEVE ANALYSIS]DATE: 2/22/2021 CHECKED BY: WRR DRAWN BY: MAE PROJECT NO.: 20212729.001A 0 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 90 100 110 ATTERBERG LIMITS LL PL PI Passing #200 2 Exploration ID Depth (ft.) 16 26 28 31 77 10 7.5 CL-ML LIQUID LIMIT (LL)PLASTICITY INDEX (PI)CL or OL "U" LINEML or OL4 7 MH or OH "A" LINE CH or O H Sample Description KB-1 KB-2 39 33 13 5 SILTY SAND (SM) SILT with SAND (ML) TABLE Testing performed in general accordance with ASTM D4318. NP = Nonplastic NM = Not Measured Burnett Ave South and Williams Ave South Water Quality Retrofit Project Renton, Washington Chart Reference: ASTM D2487PLOTTED: 02/18/2021 11:04 AM BY: WRossogINT FILE: Klf_gint_master_2021 PROJECT NUMBER: 20212729.001A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2021.GLB [_KLF_ATTERBERG (ASTM)]DATE: 2/22/2021 CHECKED BY: WRR DRAWN BY: MAE PROJECT NO.: 20212729.001A For classification of fine-grained soils and fine-grained fraction of coarse-grained soils. APPENDIX C BORING LOGS FOR PRIOR STUDIES ___________________________________________________________________________________ 97 60 39 47 14 1.6 ASPHALT: 4 inch asphalt section CONCRETE: 7 inch concrete section Fill Silty SAND with Gravel (SM): brown, moist, loose to very loose, fine-grained sand gravel grades fine to coarse-grained SILT with Sand (ML): brown, moist, very soft, non-plastic Silty SAND (SM): brown, moist, very loose, fine grained sand trace gravel, grades to medium dense Alluvium Well-Graded GRAVEL with Sand (GW): brown, moist, medium dense to dense, fine-grained gravel, fine to coarse grained sand becomes wet sample obsrtucted by well preserved piece of wood, trace sand Silty SAND (SM): brown, wet, very loose, trace wood fragments Poorly Graded GRAVEL with Sand (GP): wet, medium dense, fine gravel PID= 0.0 ppm PID= 0.0 ppm PID= 0.0 ppm PID= 0.0 ppm PID= 0.0 ppm PID= 2.3 ppm PID= 0.0 ppm BC=0 1 3 BC=0 1 1 BC=2 6 12 BC=9 17 18 BC=4 5 6 BC=12 21 14 BC=1 0 1 NP NP NP NP NP NP 4" 18" 12" 11" 10" 12" 11" SM SM GW 27.1 164.0 8.4 3.9 5.8 235.3 29.8 1 of 2 LABORATORY RESULTS Lithologic Description PAGE: FIELD EXPLORATION APPENDIX C-1 BORING LOG KB-04 BORING LOG KB-04Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%)Latitude: 47.48127° Longitude: -122.20685° Approximate Ground Surface Elevation (ft.): 30 Surface Condition: Asphalt NAD83 Gregory DrillingDrilling Company: Drilling Method: Drilling Equipment: 9/26/2019 Clear, 60's Exploration Diameter: Hammer Type - Drop:140 lb. Auto - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: CME-75 (truck-mounted) 8 inch in. O.D. S. Lewis Hollow Stem AugerPlunge:-90 degrees Justin/Michael/Ryan Additional Tests/RemarksBlow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitPlasticity Index(NP=NonPlastic)CITY OF RENTON DOWNTOWN UTILITY IMPROVEMENTS RENTON, WASHINGTONDepth (feet)5 10 15 20 25 30ApproximateElevation (feet)25 20 15 10 5 0 Graphical LogSampleNumberRecovery(NR=No Recovery)USCSSymbolWaterContent (%)1 2 3 4 5 6 7 DATE: 10/20/2019 DRAWN BY: BCO REVISED: - PROJECT NO.: 20181376 CHECKED BY: MBB gINT FILE: Klf_gint_master_2018 PROJECT NUMBER: 20181376.003A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2018.GLB [__KLF_BORING/TEST PIT SOIL LOG]PLOTTED: 01/06/2020 12:47 PM BY: MAEvansSample Type Poorly Graded GRAVEL with Sand (GP): wet, medium dense, fine gravel grades to dense Poorly Graded SAND with Gravel (SP): wet, dense, medium to coarse-grained gravel, fine sand, trace silt The boring was terminated at approximately 46.5 ft. below ground surface. Boring was backfilled with bentonite and patched with dyed concrete on September 26, 2019. PID= 0.0 ppm PID= 0.0 ppm PID= 0.0 ppm BC=5 8 11 BC=7 19 18 BC=6 20 22 GROUNDWATER LEVEL INFORMATION: Groundwater observed at approximately 20 ft bgs during drilling GENERAL NOTES: The exploration location and elevation are approximate and were estimated by Kleinfelder. 8" 6" 12" 8.7 8.3 19.0 2 of 2 LABORATORY RESULTS Lithologic Description PAGE: FIELD EXPLORATION APPENDIX C-2 BORING LOG KB-04 BORING LOG KB-04Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%)Latitude: 47.48127° Longitude: -122.20685° Approximate Ground Surface Elevation (ft.): 30 Surface Condition: Asphalt NAD83 Gregory DrillingDrilling Company: Drilling Method: Drilling Equipment: 9/26/2019 Clear, 60's Exploration Diameter: Hammer Type - Drop:140 lb. Auto - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: CME-75 (truck-mounted) 8 inch in. O.D. S. Lewis Hollow Stem AugerPlunge:-90 degrees Justin/Michael/Ryan Additional Tests/RemarksBlow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitPlasticity Index(NP=NonPlastic)CITY OF RENTON DOWNTOWN UTILITY IMPROVEMENTS RENTON, WASHINGTONDepth (feet)40 45 50 55 60 65ApproximateElevation (feet)-10 -15 -20 -25 -30 -35 Graphical LogSampleNumberRecovery(NR=No Recovery)USCSSymbolWaterContent (%)8 9 10 DATE: 10/20/2019 DRAWN BY: BCO REVISED: - PROJECT NO.: 20181376 CHECKED BY: MBB gINT FILE: Klf_gint_master_2018 PROJECT NUMBER: 20181376.003A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2018.GLB [__KLF_BORING/TEST PIT SOIL LOG]PLOTTED: 01/06/2020 12:47 PM BY: MAEvansSample Type 2" SCH 40 Solid PVC Riser 2" SCH 40 Slotted 0.010 PVC Screen Portland Cement Grout Bentonite Chips Sand Pack grass/mulch over 12 inches of topsoil (Fill) Silty SAND with Gravel (SM): dark brown, moist, very loose to medium dense trace organics trace organics wood stuck in sampler (Fill) Poorly Graded GRAVEL with Silt and Sand (GP-GM): brown, wet, loose Piece of wite PVC in sample rig chatter, gravels in cuttings (Alluvium) Poorly Graded SAND with Gravel (SP): fine to coarse-grained, sub-angular, reddish brown, wet, very loose to loose, trace silt BC=7 8 10 BC=4 6 1 BC=1 1 0 BC=2 0 1 BC=4 2 2 BC=1 1 1 BC=4 2 1 8" 4" 1" 2" 1" 4" 12" 12" 7.0 11.4 37.2 10.7 6.8 112.6 27.5 22.7 1 of 2 LABORATORY RESULTS Lithologic Description PAGE: FIELD EXPLORATION APPENDIX C-3 BORING LOG MW-5 BORING LOG MW-5 MONITORING WELL CONSTRUCTION* Completion Method: Flush mount cap in concrete Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%)Latitude: 47.48151° Longitude: -122.20797° Approximate Ground Surface Elevation (ft.): 30 Surface Condition: Asphalt NAD83 BortecDrilling Company: Drilling Method: Drilling Equipment: 4/16/2019 Cloudy/Overcast Exploration Diameter: Hammer Type - Drop:140 lb. Cathead - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: EC 95 Track Rig 8 in. O.D. R. Satyamurthy Hollow Stem AugerPlunge:-90 degrees Carlos Blow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitPlasticity Index(NP=NonPlastic)CITY OF RENTON DOWNTOWN UTILITY IMPROVEMENTS RENTON, WASHINGTONDepth (feet)5 10 15 20 25 30ApproximateElevation (feet)25 20 15 10 5 0 Graphical LogRecovery(NR=No Recovery)USCSSymbolWaterContent (%)DATE: 10/20/2019 DRAWN BY: WRR REVISED: - PROJECT NO.: 20181376 CHECKED BY: MBB gINT FILE: Klf_gint_master_2018 PROJECT NUMBER: 20181376.002A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2018.GLB [__KLF_BORING/TEST PIT SOIL LOG]PLOTTED: 01/06/2020 01:13 PM BY: MAEvansSample Type (Alluvium) Poorly Graded SAND with Gravel (SP): fine to coarse-grained, sub-angular, reddish brown, wet, very loose to loose, trace silt becomes dark brown The boring was terminated at approximately 46.5 ft. below ground surface. Monitoring Well installed to a depth of 46½ feet BC=4 3 3 BC=7 5 2 BC=13 11 12 GROUNDWATER LEVEL INFORMATION: Groundwater was observed at approximately 20 ft. below ground surface during drilling. Groundwater was observed at approximately 16 ft. below ground surface at the end of drilling. GENERAL NOTES: The exploration location and elevation are approximate and were estimated by Kleinfelder. NR 18" NR 17.2 19.3 14.9 2 of 2 LABORATORY RESULTS Lithologic Description PAGE: FIELD EXPLORATION APPENDIX C-4 BORING LOG MW-5 BORING LOG MW-5 MONITORING WELL CONSTRUCTION* Completion Method: Flush mount cap in concrete Dry Unit Wt. (pcf)Passing #4 (%)Passing #200 (%)Latitude: 47.48151° Longitude: -122.20797° Approximate Ground Surface Elevation (ft.): 30 Surface Condition: Asphalt NAD83 BortecDrilling Company: Drilling Method: Drilling Equipment: 4/16/2019 Cloudy/Overcast Exploration Diameter: Hammer Type - Drop:140 lb. Cathead - 30 in. Logged By: Date Begin - End: Hor.-Vert. Datum: Weather: Drill Crew: EC 95 Track Rig 8 in. O.D. R. Satyamurthy Hollow Stem AugerPlunge:-90 degrees Carlos Blow Counts(BC)=Uncorr. Blows/6 in.Liquid LimitPlasticity Index(NP=NonPlastic)CITY OF RENTON DOWNTOWN UTILITY IMPROVEMENTS RENTON, WASHINGTONDepth (feet)40 45 50 55 60 65ApproximateElevation (feet)-10 -15 -20 -25 -30 -35 Graphical LogRecovery(NR=No Recovery)USCSSymbolWaterContent (%)DATE: 10/20/2019 DRAWN BY: WRR REVISED: - PROJECT NO.: 20181376 CHECKED BY: MBB gINT FILE: Klf_gint_master_2018 PROJECT NUMBER: 20181376.002A OFFICE FILTER: SEATTLEgINT TEMPLATE: E:KLF_STANDARD_GINT_LIBRARY_2018.GLB [__KLF_BORING/TEST PIT SOIL LOG]PLOTTED: 01/06/2020 01:13 PM BY: MAEvansSample Type