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Home My WebLink AboutRS_Geotech_Report_1South_170922_v1 GEOTECHNICAL REPORT Elliott Bridge No. 3166 Replacement HWA Job No. 1996-143-21 Prepared for ABKJ, INC. April 4, 2003 GEOTECHNICAL REPORT Renton Fire Station 15 Renton, Washington HWA Project No. 2016-136-21 Prepared for SSW Architects, P.S. August 31, 2017 TABLE OF CONTENTS Page 1. INTRODUCTION ..........................................................................................................1 1.1 GENERAL .....................................................................................................1 1.2 PROJECT DESCRIPTION ................................................................................1 2. FIELD AND LABORATORY TESTING ...........................................................................2 2.1 GEOTECHNICAL SUBSURFACE EXPLORATIONS ............................................2 2.2 INFILTRATION TESTING PROGRAM ..............................................................3 2.3 LABORATORY TESTING ...............................................................................3 2.4 PREVIOUS EXPLORATIONS ...........................................................................3 3. SITE CONDITIONS ......................................................................................................3 3.1 GEOLOGIC CONDITIONS ..............................................................................3 3.2 SOIL CONDITIONS ........................................................................................4 3.3 GROUND WATER .........................................................................................4 4. CONCLUSIONS AND RECOMMENDATIONS ..................................................................4 4.1 GENERAL .....................................................................................................4 4.2 SEISMIC DESIGN CONSIDERATIONS .............................................................5 4.2.1 Seismic Design Parameters .............................................................5 4.2.2 Liquefaction ....................................................................................6 4.2.3 Ground Rupture ..............................................................................6 4.3 ESTIMATED SETTLEMENTS ..........................................................................6 4.4 FOUNDATION RECOMMENDATIONS .............................................................7 4.4.1 Slab-On-Grade Recommendations ...............................................7 4.5 RETAINING WALL .......................................................................................8 4.5.1 Wall Drainage ................................................................................8 4.5.2 General Wall Subgrade Preparation ...............................................8 4.6 BELOW-GRADE STRUCTURES ......................................................................9 4.7 STORMWATER MANAGEMENT .....................................................................9 4.8 BIORETENTION POND CONSTRUCTION ........................................................10 4.9 PAVEMENT ..................................................................................................10 4.9.1 Placement of HMA ........................................................................11 4.9.2 HMA Drainage...............................................................................11 4.9.3 Pervious Concrete Pavement Design .............................................12 4.9.4 Pervious Portland Cement Concrete ..............................................12 4.9.5 Recharge Bed Design and Subgrade Preparation ..........................13 4.10 SITE EARTHWORK RECOMMENDATIONS ......................................................13 4.10.1 Structural Fill and Compaction ....................................................13 4.10.2 Excavation and Temporary Shoring ............................................14 4.10.3 Wet Weather Earthwork ..............................................................15 5. CONDITIONS AND LIMITATIONS ......................................................................15 6. REFERENCES .........................................................................................................18 Table of Contents (Continued) Renton FS 15 - Final Report ii HWA GEOSCIENCES INC. LIST OF FIGURES (FOLLOWING TEXT) Figure 1. Vicinity Map Figure 2. Site and Exploration Plan Figure 3. Geologic Map Appendices Appendix A: Field Exploration Figure A-1. Legend to Symbols and Terms Used on Explorations Figures A-2 – A-4. Logs of Borings BH-4 through BH-6 Figure A-5. Log of Test Pit TP-2 Appendix B: Laboratory Testing Figures B-1 – B-7. Grain Size Distribution Test Results Appendix C: Additional Explorations Figures C-1 – C-3. Logs of Borings BH-1 through BH-3 GEOTECHNICAL REPORT RENTON FIRE STATION 15 RENTON, WASHINGTON 1. INTRODUCTION 1.1 GENERAL This report summarizes the results of geotechnical studies performed by HWA GeoSciences Inc. (HWA) for the proposed Renton Fire Station 15 project in Renton, Washington. The purpose of the work was to evaluate the soil and ground water conditions at the site and provide geotechnical recommendations for design and construction of the proposed facility. Our field work included drilling three (3) machine-drilled borings and conducting one (1) Pilot Infiltration Test (PIT) in the vicinity of the proposed fire station to evaluate soil and groundwater conditions. Laboratory tests were performed on selected soil samples to determine their relevant engineering properties. 1.2 PROJECT DESCRIPTION We understand that the City of Renton proposes to construct a fire station at 1404 N 30th Street in the Kennydale neighborhood of Renton, Washington. The addition of a new fire station will provide improved response times for fire and emergency services in the Kennydale neighborhood and the RRFA service area, relieving some of the current load placed on Fire Stations 11, 12 and 16. North of the project site, in the same parcel, the City proposes to construct a new reservoir as part of a separate project. The approximate location of the project site is shown on the Vicinity Map, Figure 1, and on the Site and Exploration Plan, Figure 2. The proposed fire station site is part of a city-owned rectangular parcel with a total existing parcel area of 47,532 SF (1.09 acres). The limits of work for the fire station project is within the southernmost subdivided lot totaling 31,173 SF (0.72 acres). We understand a reservoir is to be constructed on the northern third of the site and the fire station will be built on the southern two-thirds. HWA previously performed a geotechnical study for the proposed reservoir. The site is currently unimproved; and slopes gently upwards from the southwest to northeast, varying in elevation from approximately 208 feet to 226 feet. The fire station will be a single- story (measuring about 92 feet by 104 feet), at-grade structure with emergency vehicle equipment bays. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 2 HWA GEOSCIENCES INC. We understand that onsite infiltration is the preferred method of storm water management for this site. On-site stormwater management will be implemented via a bioretention pond and the permeable pavement facility. Additional site improvements are expected to include a below- grade storm water detention vault. An approximately 3-foot tall retaining wall is to be constructed east of the fire station building accommodate grade changes. 2. FIELD AND LABORATORY TESTING 2.1 GEOTECHNICAL SUBSURFACE EXPLORATIONS In support of design of the proposed Renton Fire Station 15 project, HWA drilled three (3) exploratory borings, designated BH-4 through BH-6, in sequence with borings drilled for the reservoir project to the north. The locations of these borings are shown on Figure 2. The borings were drilled by Environmental Drilling Inc. (EDI) of Snohomish, Washington, under subcontract to HWA. The drilling was performed using a B-61 mobile truck rig equipped with a 4.25-inch inside-diameter hollow-stem auger and an automatic hydraulic hammer. In each boring, Standard Penetration Test (SPT) sampling was performed at selected intervals and the SPT resistance (“N-value”) of the soil was logged. This resistance, or N-value, provides an indication of relative density of granular soils and the relative consistency of cohesive soils. Boring BH-4 was positioned near the center of the proposed fire station. It was drilled to a depth of 31.5 feet below ground surface. Boring BH-5 was drilled to a depth of 44 feet below ground surface near the proposed below grade storm water vault. Boring BH-6 was drilled to a depth 31.5 feet below ground surface north of the proposed fire station location. In each boring, Standard Penetration Test (SPT) sampling was performed at selected intervals and the SPT resistance (“N-value”) of the soil was logged. This resistance, or N-value, provides an indication of relative density of granular soils and the relative consistency of cohesive soils. A geologist from HWA logged the explorations and recorded pertinent information, including sample depths, stratigraphy, soil engineering characteristics, and ground water occurrence. Soil samples obtained from the exploration were classified in the field and representative portions were placed in plastic bags. These soil samples were taken to our Bothell, Washington, laboratory for further examination and testing. Logs for borings BH-4 through BH-6 are presented in Appendix A of this report. The stratigraphic contacts shown on the exploration logs represent the approximate boundaries between soil types; actual transitions may be more gradual. The soil and ground water August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 3 HWA GEOSCIENCES INC. conditions depicted are only for the specific date and location reported and, therefore, are not necessarily representative of other locations and times. 2.2 INFILTRATION TESTING PROGRAM Phase 2 of our exploration program consisted of conducting one (1) Pilot Infiltration Test (PIT), designated PT-2, in sequence with the PIT conducted for the reservoir project. The excavation for the PIT was conducted by Kelly’s Excavating Inc. of Pacific, Washington, under subcontract to HWA. PT-2 was initially excavated to a depth of 7 feet bgs and a small-scale PIT was performed. Following the PIT, PT-2 was excavated to a depth of 13 feet to evaluate soils below the test. Phase 2 of explorations was conducted on July 24 and 25, 2017. An HWA geologist logged the exploration and recorded all the pertinent information including sample depths, stratigraphy, soil engineering characteristics, and ground water occurrence at the time of excavation. More information regarding the PIT procedure is presented in Section 4.7 of this report. 2.3 LABORATORY TESTING Laboratory tests included determination of natural moisture content and grain size distribution. All testing was conducted in general accordance with appropriate American Society for Testing and Materials (ASTM) standards, as discussed in Appendix B. The test results and a discussion of laboratory test methodology are presented in Appendix B, or displayed on the boring logs in Appendix A, as appropriate. 2.4 PREVIOUS EXPLORATIONS Boring logs from previous geotechnical explorations, performed for the Kennydale 320 Pressure Zone Reservoir by HWA in 2015, were reviewed and utilized in this study. Copies of these boring logs are provided in Appendix C. 3. SITE CONDITIONS 3.1 GEOLOGIC CONDITIONS General geologic information for the project area was obtained from the Geologic Map of King County (Booth et. al., 2006). A portion of this geologic map is shown in Figure 3 of this report. The map indicates the project vicinity is underlain by deposits of the Fraser glaciation described as Vashon recessional outwash. Recessional outwash deposits consist of material washed out of a melting glacier and are characterized by stratified sand and gravel. These soils are moderately to well sorted, with less common silty sand and rare silty clay. These materials have not been glacially overridden and are typically loose to medium dense. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 4 HWA GEOSCIENCES INC. 3.2 SOIL CONDITIONS Our interpretations of subsurface conditions are based on results of our field explorations, review of available geologic and geotechnical data, and our experience in similar geologic settings. In general, the soils underlying the site consist of loose to medium dense, recessional outwash sands over medium dense to dense weathered till. Each major soil unit is described below, with materials interpreted as being youngest in origin and nearest to the surface described first. • Recessional Outwash: Recessional outwash consisting of loose to medium dense, olive brown, clean to silty sand to sandy silt, was encountered in all the explorations. Borings BH-4 and BH-6 and test pit TP-2 were terminated within the recessional outwash soils. Recessional outwash was deposited by meltwater emanating from the retreating glacial ice sheet. Consequently, it has not been overridden by glacial ice and is typically loose to medium dense. The upper 5 to 7 feet of recessional outwash typically consisted of loose to medium dense, sandy silt. It should be noted that a large boulder was partially exposed in TP-2 at about 5 feet bgs. • Weathered Till: Weathered till was encountered in boring BH-5 below the recessional outwash sands. This unit consisted of very stiff sandy silt and medium dense to dense, silty, gravelly sand. Previous explorations at the site to the north encountered glacial till below the recessional outwash deposits, as indicated in the logs of borings BH-1 and BH-2, which are presented in Appendix C. Although not encountered in our borings, cobbles and boulders are known to exist in glacial deposits. 3.3 GROUND WATER At the time of our field investigation, perched ground water seepage was observed only in boring BH-5 at a depth 32.5 feet below ground surface. The ground water seepage observed may not necessarily be indicative of other times and/or locations and it is anticipated that ground water conditions will vary depending on the weather, local subsurface conditions, and other factors. 4. CONCLUSIONS AND RECOMMENDATIONS 4.1 GENERAL The proposed fire station site is underlain by recessional outwash over weathered till soils. The recessional outwash will provide suitable bearing for the proposed structure. The loose to medium dense, recessional outwash sands will experience elastic settlement due to the increases in load associated with the proposed structure. However, most of this settlement will occur during construction. We recommend the structure be designed and constructed with spread footing foundations bearing on a layer of compacted structural fill placed over the native soils. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 5 HWA GEOSCIENCES INC. Because the upper 5 to 7 feet of outwash soils are relatively loose, we recommend they be compacted prior to construction of foundations. We recommend that the building site be excavated to the proposed floor subgrade level and then compacted by at least 4 complete coverages with a 10-ton (minimum static weight) vibratory roller. In addition, individual footing subgrades should be compacted with a backhoe-mounted vibratory plate compactor (hoepac). On-site stormwater management will be implemented via a bioretention pond and the permeable pavement facility. It should be noted that sandy silt soils with high percentage of fines were encountered near the ground surface (about 5-7 feet below ground surface). These soils are not conducive to infiltration. Therefore, we recommend to over-excavate the upper fine-grained material (sandy silt soils) and backfill with free-draining granular material such as pea gravel. The granular material placed underneath the pervious pavement and/or bioretention pond should not be compacted. Recommendations related to site seismicity, foundations, retaining walls, utilities, below-grade structures, stormwater management, earthwork, and pavement are presented in the following sections. 4.2 SEISMIC DESIGN CONSIDERATIONS 4.2.1 Seismic Design Parameters Earthquake loading for the structures at the project site was developed in accordance with the 2012 International Building Code (IBC), (ICC, 2012). The IBC requires above-grade structures be designed for the inertial forces induced by a “Maximum Considered Earthquake” (MCE), which corresponds to an earthquake with a 2% probability of exceedance (PE) in 50 years (approximately 2,475-year return period). Accordingly, the relevant probabilistic spectral response parameters were developed using the United States Geological Survey’s website. The IBC accounts for the effects of site-specific subsurface ground conditions on the response of structures in terms of site classes. Site classes are defined by the average density and stiffness of the soil profile underlying the site. The Site Class can be correlated to the average standard penetration resistance (NSPT) in the upper 100 feet of the soil profile. Based on our characterization of the subsurface conditions, the subject site classifies as IBC Site Class D. Table 1 presents the design spectral seismic coefficients obtained for this site based on risk category I/II/III. The design peak ground acceleration for use in computing lateral earth pressures was computed to be 0.385 g. Based on the SDS and SD1 values, the site is considered as Seismic Design Category D. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 6 HWA GEOSCIENCES INC. Table 1. Design Seismic Coefficients for IBC 2012 Code Based Evaluation Site Class Spectral Acceleration at 0.2 sec. SS(1), g Spectral Acceleration at 1.0 sec S1(2), g Design Spectral Acceleration at 0.2 sec. SDS(3), g Design Spectral Acceleration at 1.0 sec. SD1(4), g Site Coefficients Peak Horizontal Acceleration PGA, (g) Fa(5) Fv(6) D 1.444 0.546 0.963 0.546 1.000 1.500 0.385 (1) SS = Mapped spectral response acceleration parameter at short periods (at a period of 0.2 sec) (2) S1 = Mapped spectral response acceleration parameter at a period of one second (3) SDS = Design spectral response acceleration parameter at short periods (at a period of 0.2 sec) (4) SD1 = Design spectral response acceleration parameter at a period of one second (5) Fa = short period site coefficient (at a period of 0.2 sec) (6) Fv = long period site coefficient (at a period of one second) The project site is located within about 2 miles of the Seattle Fault Zone. The main seismic consideration for the site is the large amplitude of the ground motions associated with its proximity to the fault, which is accounted for in the design seismic coefficients. With respect to the design parameters for the vertical accelerations, the recommendations provided in the ASCE 7-10 Section 12.4.2.2 (ASCE, 2010) should be applied. 4.2.2 Liquefaction Primary factors controlling the development of liquefaction include the intensity and duration of strong ground motions, the characteristics of subsurface soils, in-situ stress conditions and the depth to ground water. Based on the ground water elevations observed in our explorations, the materials that are saturated are dense to very dense and will not be subject to liquefaction during shaking. Therefore, liquefaction is not a design consideration for this project. 4.2.3 Ground Rupture Based on a review of the existing geologic data, there are no known active faults at this site; therefore, ground rupture is not a design consideration. 4.3 ESTIMATED SETTLEMENTS The soils underlying the fire station site consist of recessional outwash sands over weathered glacial till. Assuming the recommendations in this report are followed, we anticipate that settlements under static loads will be no more than ½ inch. This settlement will occur during construction as the loads are applied. Settlement under the design seismic load could total an additional ¼ inch. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 7 HWA GEOSCIENCES INC. 4.4 FOUNDATION RECOMMENDATIONS The proposed fire station and retaining wall should be supported on spread footings or mat foundations designed for a maximum allowable bearing pressure of 3,000 pounds per square foot. For short-term wind and seismic loading conditions, the allowable bearing pressure may be increased by 1/3. Footings should have a minimum footing width of 24 inches and should bear at least 18 inches below the lowest adjacent finished grade. Individual footing subgrades should be compacted with a hoepac prior to placement of formwork, steel, or concrete. The footings should be supported on a minimum of 1-foot of structural fill placed directly over the compacted native soils. Structural fill should consist of Crushed Surfacing Top Course (CSTC) as specified in Section 9-03.9(3) of the WSDOT Standard Specifications (WSDOT, 2016). Any soft or disturbed soils and any soil containing organic material (unsuitable material) should be removed under the observation of an HWA engineer or geo-technician to verify competent native soils are exposed. Wind and seismic transient lateral forces on the structure will be resisted by friction along the footings, and by passive soil pressure against the buried portions of the footings. An ultimate coefficient of friction of 0.5 may be assumed for cast-in-place concrete on granular material. Also, a passive resistance to lateral loads maybe estimated as an equivalent fluid pressure of 250 pcf. These are ultimate resistance values, and an adequate factor of safety should be applied in design calculations. Perimeter footing drains should be installed around the entire building exterior. The perimeter footing drains should consist of 4-inch diameter, perforated, rigid plastic pipes, bedded and backfilled with Gravel Backfill for Drains, as specified in Section 9-03.12(4) of the 2016 WSDOT Standard Specifications. Footing drain inverts should be at least 12 inches lower than the bottom of floor slabs. Footing drains should be sloped to drain into an appropriate outlet, such that storm water cannot backup around the footings. Roof drains should not be tied into the perimeter drain system to prevent potential backup into the perimeter drains during intense storm events. The ground surface should be graded to direct surface water away from the structures. 4.4.1 Slab-On-Grade Recommendations The slab-on-grade should be supported on a minimum of 1-foot of structural fill placed directly over the compacted native soils. Structural fill should consist of Crushed Surfacing Top Course (CSTC). Any soft or disturbed soils and any soil containing organic material (unsuitable material) should be removed under the observation of an HWA engineer or geo-technician to verify competent native soils are exposed. Because the ground surface slopes down to the west, the structural fill thickness will likely vary across the slab footprint. If the fill material is poor or if compaction is inadequate, the variable structural fill thickness could lead to differential settlement in the fill, resulting in the formation of cracks greater than the tolerable limits for the serviceability of the apparatus bay floor. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 8 HWA GEOSCIENCES INC. The recommended structural fill should be compacted to at least 95% of its maximum dry density, based on the Modified Proctor Test. Slab-on-grade floors should be underlain by a capillary break layer consisting of at least 6 inches of washed 3/8-inch pea gravel. A 10-mil (minimum thickness) plastic vapor barrier should be placed over this capillary break layer. Joints in the vapor barrier should overlap at least 2 feet or be sealed with adhesive or double-sided tape in accordance with the manufacturer’s recommendations. A 2-inch thick layer of concrete sand may be placed over the vapor barrier to protect the vapor barrier and to provide for more uniform concrete curing. Placement of the vapor barrier should be undertaken with care, and construction activity on the membrane should be limited after placement to avoid perforations in the membrane. 4.5 RETAINING WALL It is our understanding that a 3-feet tall, cast-in-place retaining wall will be required at the east side of the fire station to accommodate changes in grade. The location of the wall is shown on the Site and Exploration Plan, Figure 2. Wall design should provide resistance for the lateral earth pressures from the retained soil. For wall design, the at-rest lateral earth pressure for design of the wall should be 57 pounds per cubic foot (pcf). This earth pressure assumes that the wall is backfilled with well compacted structural fill. This assumes that no ground water pressures develop behind the wall, which is appropriate assuming adequate drainage measures are provided. We recommend the Contractor be required to submit the proposed wall design for approval by the Engineer. 4.5.1 Wall Drainage Drainage should be provided to prevent the buildup of hydrostatic pressures behind all retaining walls. Drainage should consist of a perforated drain pipe at the base of the wall, embedded in Gravel Backfill for Drains, per WSDOT Standard Specification Section 9-03.12(4) (WSDOT, 2016). The drain pipe should be graded to direct water from the backfill and subgrade soils to a suitable outlet. 4.5.2 General Wall Subgrade Preparation Subgrade preparation is important to limit differential settlement of the wall and maintain global stability. All organic material should be removed. Loose or soft soils, defined as being penetrable more than 1 foot with a 1/2-inch diameter rod pushed in under a 150 lb load (T-probe pushed in by hand), should be removed and replaced with structural backfill or be suitably compacted. The area on which the wall will rest should be graded level perpendicular to the wall face and compacted in accordance with WSDOT Standard Specifications Section 2-03.3(14)D (WSDOT, 2016). It should be noted that 5 to 7 feet of loose/soft silt material was encountered in our explorations. This material is not suitable for wall base. Therefore, we recommend the wall August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 9 HWA GEOSCIENCES INC. be founded on a 1-foot thick leveling pad constructed of compacted Crushed Surfacing Top Course (CSTC) placed over compacted native soils. Fill against an existing slope will require terraced cuts as outlined in WSDOT Standard Specifications Section 2-03.3(14), Embankment Construction (WSDOT, 2016). 4.6 BELOW-GRADE STRUCTURES All below grade structures should be designed with consideration of the anticipated lateral earth pressures that will be applied on the structures. We expect that these buried structures will not be free to yield and will develop at-rest earth pressures upon backfilling. These structures should be designed to resist an equivalent fluid pressure of at least 60 pounds per cubic foot (pcf). This earth pressure assumes no accumulation of water behind the wall. Proper drainage should be provided to ensure that hydrostatic pressures do not develop behind these structures. Where drainage is not provided, the structure should be designed for an allowable equivalent fluid pressure of 120 pcf. Under earthquake loading conditions, the buried structures will experience an incremental additional horizontal earth pressure. This increment can be approximated using the Mononobe- Okabe method utilizing 0.5 times the PGA for the site, (0.5)(0.385g) = 0.19g. This results in a design active-plus-seismic earth pressure coefficient, Kae = 0.37. For design purposes, a design active-plus-seismic equivalent fluid pressure of 52 pcf would be slightly less than the recommended at-rest pressure of 60 pcf. 4.7 STORMWATER MANAGEMENT It is our understanding that the City would like to utilize onsite infiltration as a means of stormwater management for the project. On-site stormwater management will be implemented via a bioretention pond and the permeable pavement facility. Pilot Infiltration Testing (PIT) was performed in general accordance with the King County, Washington, Surface Water Design Manual (King County, 2016). HWA conducted a PIT in the vicinity of the proposed bioretention pond, north of borehole BH-5 on the northeast corner of the proposed fire station. The PIT was dug 7 feet into the ground to remove surficial topsoil and upper layers of silt and silty sands. Slightly cleaner sands were encountered at 7 feet below the ground surface where the test was performed. The dimensions of the test pit inside of the excavation area were 3.5 feet by 5 feet. The test consisted of introducing water at a known flow rate into the excavation. Water was obtained from a nearby water service in cooperation with the City of Renton Utility Division and pumped into the excavation using a water trailer provided by Kelly’s Excavating, Inc. Slotted pipe terminating in a 5-gallon bucket was used to dissipate the water into the excavation. Water levels were measured with a staff gauge installed in the excavation along with a Levelogger August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 10 HWA GEOSCIENCES INC. Edge water level datalogger. At selected intervals, HWA recorded total flow through a meter and calculated the flow rate. The flow rate was adjusted to establish and maintain a water level of approximately 1 foot above the base of the PIT. After approximately 7 hours of flow, the water was turned off. Water levels in the excavation were monitored until all the water had drained out of the test pit. The rate of water level decline after the water was turned off was used to determine the flow rate as the head approached zero, which was used to determine the short term, field measured infiltration rate. Based on the test results, we recommend a long-term infiltration rate of 1.1 in/hr, assuming the removal of the upper 7 feet of soil (silty material). 4.8 BIORETENTION POND CONSTRUCTION The project proposes a 20-feet long by 18-feet wide bioretention pond, with a total designed volume of 122 cubic feet. The bioretention area consists of 18-inches of bioretention soil mix underlain by 18-inches of drain rock over the native subgrade. However, sandy silt soils with high percentage of fines were encountered near the ground surface (about 5-7 feet below ground surface). These soils are not conducive to infiltration. Therefore, we recommend to over- excavate the fine-grained material (sandy silt soils) and backfill with free-draining granular material such as pea gravel. It should be noted that the structural fill placed underneath the bioretention pond should not be compacted. 4.9 PAVEMENT It is our understanding that a 16 to 24 feet wide access road will be designed to provide access to maintenance vehicles as shown on the Site and Exploration Plan, Figure 2. This access road will consist of a combination of Hot Mix Asphalt (HMA) and pervious concrete. We understand that this road will be used primarily by service vehicles and not by heavy equipment or heavy trucks. Therefore, for the HMA portion, we recommend a new pavement section consisting of 4 inches of HMA over 6 inches of compacted Crushed Surfacing Base Course (CSBC), as shown in Table 2. Table 2. Structure Requirements for New HMA Pavement Material Description Minimum Layer Thickness (inches) WSDOT Standard Specification HMA 4 5-04 CSBC 6 9-03.9(3) Structural Fill/Prepared Subgrade Proof-roll 9-03.14(1) August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 11 HWA GEOSCIENCES INC. The pavement layer thicknesses given in Table 2 do not account for heavy construction traffic. If a significant volume of construction traffic (mainly fully-loaded trucks) will operate over the completed base before placement of the surfacing, or if the moisture content of the subgrade is elevated as result of rainfall, then heaving and rutting could occur. In such cases, the thickness of base, or structural fill, should be increased. One to two feet of structural fill/quarry spalls may be required below the CSBC to provide a base for the compacted materials above. We recommend that the asphalt layers consist of HMA Class ½-inch. The maximum lift thickness for HMA Class ½-inch is 0.3 feet (or 3.6 inches), as stipulated by WSDOT (WSDOT, 2016). 4.9.1 Placement of HMA Placement of HMA should be in accordance with Section 5-04 of the WSDOT Standard Specifications (WSDOT, 2016). Particular attention should be paid to the following: HMA should not be placed until the engineer has accepted the previously constructed pavement layers. HMA should not be placed on any frozen or wet surface. HMA should not be placed when precipitation is anticipated before the pavement can be compacted, or before any other weather conditions which could prevent proper handling and compaction of HMA. HMA should not be placed when the average surface temperatures are less than 45o F. HMA temperature behind the paver should be in excess of 240o F. Compaction should be completed before the mix temperature drops below 180o F. Comprehensive temperature records should be kept during the HMA placement. For cold joints, tack coat should be applied to the edge to be joined and the paver screed should be set to overlap the first mat by 1 to 2 inches. 4.9.2 HMA Drainage It is essential to the satisfactory performance of the roadway that good drainage is provided to prevent water ponding alongside the pavement causing saturation of the pavement and subgrade layers. The base layers should be graded to prevent water being trapped within the layer. The surface of the pavement should be sloped to convey water from the pavement to appropriate drainage facilities. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 12 HWA GEOSCIENCES INC. 4.9.3 Pervious Concrete Pavement Design It is our understanding that a section of the access road and the parking area located north of the fire station will consist of pervious concrete pavement. It should be noted that sandy silt soils with high percentage of fines were encountered near the ground surface (about 5-7 feet below ground surface). These soils are not conducive to infiltration. Therefore, we recommend to over-excavate the upper fine-grained material (sandy silt soils) to expose the clean native soils and backfill with free-draining granular material such as pea gravel. The granular material placed underneath the pervious pavement should not be compacted. In general, pervious pavement sections consist of a wearing course, a choker course, a recharge bed course, and a carefully prepared subgrade. Regardless of the type of the wearing course used, the size and composition of the remaining courses are generally the same. Table 3 presents our recommendations for the pervious concrete pavement section. The following sections provide our recommendations for each component of the pervious pavement section. Table 3. Structure Requirements for New Pervious PCC Pavement Material Description Minimum Layer Thickness (inches) WSDOT Standard Specification PCC Wearing Surface 6 5-05 Choker Course (AASHTO No. 57) 1 - Recharge Bed (AASHTO No. 2) Varies (18-36) Section 5.05.2 Non-Woven Geosynthetic - 9-33.2(1) Prepared Subgrade Uncompacted Section 5.05.3 4.9.4 Pervious Portland Cement Concrete Based on the anticipated light loading conditions and the nature of pervious concrete pavement, it is our recommendation that this pavement section consist of a minimum of 6 inches of pervious Portland cement concrete pavement. Pervious Portland cement concrete is typically a proprietary product that is readily available by many local concrete batch plants. In general, the pervious concrete mix uses uniformly graded crushed coarse aggregate (e.g. meeting AASHTO grading No. 8) with no, or limited use of, fine aggregate and a water to cement ratio ranging from 0.27 to 0.35. The 28-day compressive August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 13 HWA GEOSCIENCES INC. strength of the mix is typically between 2,500 psi and 4,000 psi with an average modulus of rupture of about 350 to 375 psi. The unit weight of the mix is between 100 and 125 pcf with a porosity of 15% to 25%. The permeability of the hardened product is between 300 and 800 in/hr. We recommend that expansion joints be saw cut into the concrete at spacings of no greater than 12 feet to limit post construction cracking. These joints need not be sealed. Maintenance practices for cleaning pervious concrete should be implemented to maintain permeability. Some cleaning techniques are pressure washing, vacuum sweeping and/or a combination of these two methods. 4.9.5 Recharge Bed Design and Subgrade Preparation Recharge beds under pervious pavements should be adequately sized to provide sufficient storage during the 2-year design storm, and should also include an overflow system (or under- drain system) to handle peaks of more intense (25 or 50-year) storms. Typical bed thicknesses range between 1.5 feet and 3 feet. The drain aggregate in the recharge bed should consist of 1 inch to 1.5 inch crushed, washed drain rock, or 1.5 to 2.5 inch washed crushed base aggregate such as AASHTO No. 2. The coarse gravel should be placed in 8-inch thick (maximum) loose lifts with each layer compacted lightly while keeping compaction equipment movement over recharge bed subgrade to a minimum. A design value of 0.3 should be used for the porosity of the base aggregate. A 1-inch thick choker course consisting of uniformly graded gravel, such as size AASHTO No.57 aggregate, should be placed over the surface of the recharge bed to provide an adequate platform for the porous wearing surface. A nonwoven geotextile meeting the material requirements of WSDOT Standard Specifications (WSDOT, 2016) Section 9-33.1, with the properties listed in Section 9-33.2(1) Table 3 for Separation, should be placed along the sides of the excavation between the native and the drain aggregate to prevent migration of fines into the recharge bed. The nonwoven geotextile should not be placed below the pervious wearing surface over the top of the recharge bed aggregate. Placing nonwoven geotextile below the pervious wearing surface could result in clogging of the geotextile over time, reducing the functionality of the system. 4.10 SITE EARTHWORK RECOMMENDATIONS 4.10.1 Structural Fill and Compaction All fill placed at this site should be considered structural fill. Structural fill materials should consist of clean, free-draining, granular soils free from organic matter or other deleterious August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 14 HWA GEOSCIENCES INC. materials. The native soils along the project alignment are not suitable for reuse as structural fill for this project. Such imported materials should be less than 4 inches in maximum particle dimension, with less than 7 percent fines (portion passing the U. S. Standard No. 200 sieve), as specified for Gravel Borrow in Section 9-03.14(1) of the WSDOT Standard Specifications (WSDOT, 2016) or Crushed Surfacing Top Course (CSTC) as specified in Section 9-03.9(3) of the WSDOT Standard Specifications (WSDOT, 2016). The fine-grained portion of structural fill soils should be non-plastic. All fill, except for fill required underneath the pervious concrete and bioretention pond, should be placed in lifts and compacted to at least 95 percent of the maximum dry density, as determined using test method ASTM D 1557 (Modified Proctor). The thickness of loose lifts should not exceed 8 inches for heavy weight compactors and 4 inches for hand-operated equipment. The procedure to achieve the specified minimum relative compaction depends on the size and type of compacting equipment, the number of passes, thickness of the layer being compacted, and certain soil properties. We recommend that the appropriate lift thickness, and the adequacy of the subgrade preparation and materials compaction be evaluated by a representative of the geotechnical engineer during construction. A sufficient number of in-place density tests should be performed as the fill is being placed to verify that the required compaction is achieved. 4.10.2 Excavation and Temporary Shoring Excavations for the new foundations and below grade structures can be accomplished with conventional excavating equipment such as backhoes. We recommend that foundation excavation be accomplished with a smooth (toothless) bucket to minimize disturbance of subgrade soils. Any loosened or disturbed soils should be removed. It is our understanding that the proposed storm water facility is to extend approximately 9 feet below existing grade. Sloped excavations and/or standard trench box shoring may be used as means of temporary shoring. Maintenance of safe working conditions, including temporary excavation stability, is the responsibility of the contractor. In accordance with Part N of Washington Administrative Code (WAC) 296-155, latest revisions, all temporary cuts in excess of 4 feet in height must be either sloped or shored prior to entry by personnel. The existing granular soils on site are generally classified as Type C soils, per WAC 296-155. Where shoring is not used, temporary cuts in Type C soils should be sloped no steeper than 1½H:1V (horizontal: vertical). It is important that the contractor monitors the stability of temporary cut slopes and adjusts the construction schedule and slope inclination accordingly. August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 15 HWA GEOSCIENCES INC. 4.10.3 Wet Weather Earthwork During period of wet weather, even the most permeable soils can become difficult to work and compact. Given that the near surface soils across most of the site consist of recessional outwash sand, we expect variability in the fines content of these native soils. Soils with higher fines contents will be hard to compact when above a given moisture content (generally about 10 to 12 percent moisture). As a result, the moisture content of these soils may be difficult to control during periods of wet weather. If fill is to be placed or earthwork is to be performed in wet weather or under wet conditions, the following recommendations apply: • Earthwork should be accomplished in small sections to minimize exposure to wet weather. Excavation or the removal of unsuitable soil should be followed promptly by the placement and compaction of a suitable thickness of clean structural fill or lean concrete. The size and type of construction equipment used may need to be limited to prevent soil disturbance; • Material used as structural fill should consist of clean, granular soil, of which not more than 5 percent by dry weight passes the U.S. Standard No. 200 sieve, based on wet sieving the fraction passing the ¾-inch sieve; this is an additional restriction for the structural fill materials described in Section 4.10.1. The fine-grained portion of the structural fill soils should be non-plastic; • The ground surface within the construction area should be sloped and sealed with a smooth drum vibratory roller to promote rapid runoff of precipitation and to prevent ponding of water; • No soil should be left uncompacted so it can absorb water. Soils which become too wet for compaction should be removed and replaced with clean granular materials; and • Excavation and placement of fill should be observed on a full-time basis by a person experienced in wet weather earthwork to verify that all unsuitable materials are removed and suitable compaction and site drainage are achieved. The above recommendations for wet weather earthwork should be incorporated into the contract specifications. 5. CONDITIONS AND LIMITATIONS We have prepared this report for the City of Renton and SSW Architects, P.S., for use in design phase of this project. This report should be provided in its entirety to prospective contractors for bidding and estimating purposes; however, the conclusions and interpretations presented herein August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 16 HWA GEOSCIENCES INC. should not be construed as a warranty of the subsurface conditions. Experience has shown that soil and groundwater conditions can vary significantly over small distances. Inconsistent conditions can occur between explorations that may not be detected by a geotechnical study. If, during future site operations, subsurface conditions are encountered which vary appreciably from those described herein, HWA should be notified for review of the recommendations of this report, and revision of such if necessary. If there is a substantial lapse of time between submission of this report and the start of construction, or if conditions change due to construction operations at or adjacent to the project site, it is recommended that this report be reviewed to determine the applicability of the conclusions and recommendations considering the changed conditions and time lapse. This report is issued with the understanding that it is the responsibility of the owner, or the owners’ representative, to ensure that the information and recommendations contained herein are brought to the attention of the appropriate design team personnel and incorporated into the project plans and specifications, and the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field. HWA is available to monitor construction to evaluate soil and groundwater conditions as they are exposed and verify that subgrade preparation, fill placement and compaction, and pile installation are accomplished in accordance with the project specifications. Within the limitations of scope, schedule and budget, HWA attempted to execute these services in accordance with generally accepted professional principles and practices in the fields of geotechnical engineering and engineering geology at the time the report was prepared. No warranty, express or implied, is made. The scope of our work did not include environmental assessments or evaluations regarding the presence or absence of wetlands or hazardous or toxic substances in the soil, surface water, or groundwater at this site. HWA does not practice or consult in the field of safety engineering. We do not direct the contractor’s operations, and cannot be responsible for the safety of personnel other than our own on the site. As such, the safety of others is the responsibility of the contractor. The contractor should notify the owner if he considers any of the recommended actions presented herein unsafe.      August 31, 2017 HWA Project No. 2016-136-21 Renton FS 15 - Final Report 18 HWA GEOSCIENCES INC. 6. REFERENCES American Association of State Highway and Transportation Officials (AASHTO), 1993, AASHTO Guide for Design of Pavement Structures, American Association of State Highway and Transportation Officials. Booth, D.B. and Wisher, A.P. 2006. Geologic Map of King County 1:100,000 Quadrangles, Washington, Department of Earth and Space Sciences, University of Washington, GeoMapNW. International Code Council, 2012. International Building Code, 2012, published May, 2011, International Code Council, Falls Church, VA. King County Department of Natural Resources and Parks, April 2016. King County, Washington Surface Water Design Manual. Tokimatsu, K. and H.B. Seed, 1987. Evaluation of settlements in sands due to earthquake shaking, J. Geot. Engrg., 113 (8), 861-878. USGS Earthquake Hazards Program, 2002. “2002 Interactive Deaggregation”, USGS Earthquake Hazards Program, National Earthquake Hazard Maps, http://eqint.cr.usgs.gov/eq-men/html/deaggint2002. WSDOT, 2015 Geotechnical Design Manual, M 46-03.11. WSDOT, 2016. Standard Specifications for Road, Bridge and Municipal Construction, Washington State Department of Transportation. VICINITY MAP RENTON FIRE STATION 15 RENTON, WASHINGTON 1 2016-136-21 FIGURE NO. PROJECT NO. MAP NOT TO SCALE BASE MAP FROM GOOGLE MAPS DATA © 2016 GOOGLE N © 2016 Microsoft MDA Geospatial Services Inc. Lake Washington Approximate Extent of Project Site BH-1 Boring designation and approximate location. (HWA 2015) SITE AND EXPLORATION PLAN BH-4 BH-2 BH-3 BH-5 FIGURE NO. PROJECT NO. BH-1 RENTON FIRE STATION #15 RENTON, WASHINGTON 2 2016-136-21 Proposed Location of Bioretention Pond Boring designation and approximate location. (HWA 2017) BH-4 NOT TO SCALE Pilot Infiltration Test designation and approximate location. (HWA 2017) PT-2 PT-2 PT-1 BH-6 . GEOLOGIC MAP RENTON FIRE STATION 15 RENTON, WASHINGTON 3 2016-136-21 FIGURE NO. PROJECT NO. MAP NOT TO SCALE N Approximate project site location APPENDIX A FIELD EXPLORATION A-12016-136-21 Renton Fire Statioin 15 Renton, Washington SYMBOLS USED ON EXPLORATION LOGS LEGEND OF TERMS AND to 30 over 30 Approximate Undrained Shear Strength (psf) <250 250 - No. 4 Sieve Sand with Fines (appreciable amount of fines) amount of fines) More than 50% Retained on No. 200 Sieve Size Sand and Sandy Soils Clean Gravel (little or no fines) More than 50% of Coarse Fraction Retained on No. 4 Sieve Gravel with SM SC ML MH CH OH RELATIVE DENSITY OR CONSISTENCY VERSUS SPT N-VALUE Very Loose Loose Medium Dense Very Dense Dense N (blows/ft) 0 to 4 4 to 10 10 to 30 30 to 50 over 50 Approximate Relative Density(%) 0 -15 15 -35 35 -65 65 -85 85 -100 COHESIVE SOILS Consistency Very Soft Soft Medium Stiff Stiff Very Stiff Hard N (blows/ft) 0 to 2 2 to 4 4 to 8 8 to 15 15 Clean Sand (little or no fines) 50% or More of Coarse Fraction Passing Fine Grained Soils Silt and Clay Liquid Limit Less than 50% 50% or More Passing No. 200 Sieve Size Silt and Clay Liquid Limit 50% or More 500 500 -1000 1000 -2000 2000 -4000 >4000 DensityDensity USCS SOIL CLASSIFICATION SYSTEM Coarse Grained Soils Gravel and Gravelly Soils Highly Organic Soils GROUP DESCRIPTIONS Well-graded GRAVEL Poorly-graded GRAVEL Silty GRAVEL Clayey GRAVEL Well-graded SAND Poorly-graded SAND Silty SAND Clayey SAND SILT Lean CLAY Organic SILT/Organic CLAY Elastic SILT Fat CLAY Organic SILT/Organic CLAY PEAT MAJOR DIVISIONS GW SP CL OL PT GP GM GC SW COHESIONLESS SOILS Fines (appreciable LEGEND 2016-136.GPJ 5/2/17 PROJECT NO.:FIGURE: Coarse sand Medium sand SIZE RANGE Larger than 12 in Smaller than No. 200 (0.074mm) Gravel time of drilling) Groundwater Level (measured in well or AL CBR CN Atterberg Limits: LL = Liquid Limit California Bearing Ratio Consolidation Resilient Modulus Photoionization Device Reading Pocket Penetrometer Specific Gravity Triaxial Compression Torvane 3 in to 12 in 3 in to No 4 (4.5mm) No. 4 (4.5 mm) to No. 200 (0.074 mm) COMPONENT DRY Absence of moisture, dusty, dry to the touch. MOIST Damp but no visible water. WET Visible free water, usually soil is below water table. Boulders Cobbles Coarse gravel Fine gravel Sand MOISTURE CONTENT COMPONENT PROPORTIONS Fine sand Silt and Clay 5 - 12% PROPORTION RANGE DESCRIPTIVE TERMS Clean Slightly (Clayey, Silty, Sandy) 30 - 50% Components are arranged in order of increasing quantities. Very (Clayey, Silty, Sandy, Gravelly) 12 - 30%Clayey, Silty, Sandy, Gravelly open hole after water level stabilized) Groundwater Level (measured at 3 in to 3/4 in 3/4 in to No 4 (4.5mm) No. 4 (4.5 mm) to No. 10 (2.0 mm) No. 10 (2.0 mm) to No. 40 (0.42 mm) No. 40 (0.42 mm) to No. 200 (0.074 mm) PL = Plastic Limit DD DS GS K MD MR PID PP SG TC TV Dry Density (pcf) Direct Shear Grain Size Distribution Permeability Approx. Shear Strength (tsf) Percent Fines%F Moisture/Density Relationship (Proctor) Approx. Compressive Strength (tsf) Unconfined CompressionUC (140 lb. hammer with 30 in. drop) Shelby Tube Small Bag Sample Large Bag (Bulk) Sample Core Run Non-standard Penetration Test 2.0" OD Split Spoon (SPT) NOTES: Soil classifications presented on exploration logs are based on visual and laboratory observation. Density/consistency, color, modifier (if any) GROUP NAME, additions to group name (if any), moisture content. Proportion, gradation, and angularity of constituents, additional comments. (GEOLOGIC INTERPRETATION) Please refer to the discussion in the report text as well as the exploration logs for a more complete description of subsurface conditions. Soil descriptions are presented in the following general order: < 5% 3-1/4" OD Split Spoon with Brass Rings (3.0" OD split spoon) TEST SYMBOLS SAMPLE TYPE SYMBOLS GROUNDWATER SYMBOLS COMPONENT DEFINITIONS GS GS GS %F GS S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 S-9 S-10 Soft, dark brown, sandy SILT with organics, wet. (TOPSOIL) Medium stiff, brown, sandy SILT, moist. Sand is fine to medium. Rootlets, rust mottling, and scattered anoxic decomposition (black spots) visible throughout. (RECESSIONAL OUTWASH) Loose, brown, very sandy SILT, moist. Rootlets and rust banding observed. Trace coarse sand. Loose, olive brown, very silty, fine to coarse SAND, moist. Rust staining. Silty sand layer from 8.5 to 9.0 feet. Medium dense, olive brown, silty, medium to coarse SAND with trace gravel, moist. Gravel is subrounded to subangular. Medium dense, olive brown, silty, fine to medium SAND, moist. Becomes wet. Scattered rust bands observed. Becomes olive brown to olive gray, and moist. Medium dense, olive gray, fine clean SAND, moist. Rust band observed at 20.5'. Becomes fine to medium. Becomes mostly fine sand. Olive brown silty sand layers at 31.0'. Scattered oxidation bands. Boring terminated at 31.5 feet. No groundwater observed while conducting this exploratory boring. 1-1-3 3-1-3 4-5-4 5-6-7 5-7-8 5-8-9 5-6-10 5-6-7 6-9-11 6-8-9 ML SM SP BORING-DSM 2016-136.GPJ 8/31/17 FIGURE:PROJECT NO.:2016-136-21 Renton, Washington Renton Fire Statioin 15 BH-4 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-2 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)0 5 10 15 20 25 30 35 ELEVATION(feet)DATE COMPLETED: 3/29/2017 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" IC Continuous Flight HSA LOCATION: 80.0' North of South fence; 53.9' West of East fence DATE STARTED: 3/29/2017 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar SURFACE ELEVATION: Approx. 212 feet GS GS GS GS GS %F GS %F S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 Soft, dark brown, sandy SILT with organics, wet. (TOPSOIL) Loose, dark yellowish brown, very silty SAND, moist. Rust mottling throughout sample. One gravel (1" diameter) observed at 3.0'. (RECESSIONAL OUTWASH) Medium dense, dark yellowish brown, silty, fine to medium SAND, wet. Rust bands observed throughout sample. Trace wood and some gravels at 6.0'. Clean sand band at 5.5' and 6.2'. Stiff, dark yellowish brown, very sandy SILT, moist. Bands of medium sand observed from 10.5' to 11.0'. Medium dense, dark brown, silty, fine to medium SAND, moist. Rust band observed at 13.8'. Medium dense, olive brown, slightly silty, fine to medium SAND, moist. Rust band observed at 15.3'. 2-3-5 2-3-8 3-5-8 2-3-6 4-7-11 6-6-8 5-8-8 5-7-9 SM ML SM SP SM BORING-DSM 2016-136.GPJ 5/2/17 FIGURE:PROJECT NO.:2016-136-21 Renton, Washington Renton Fire Statioin 15 BH-5 PAGE: 1 of 2(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-3 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)0 5 10 15 20 25 ELEVATION(feet)DATE COMPLETED: 3/29/2017 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" IC Continuous Flight HSA LOCATION: 46.1' East of West fence; 77.2' North of South fence DATE STARTED: 3/29/2017 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar SURFACE ELEVATION: Approx. 209 feet S-9 S-10 S-11 S-12 S-13 Becomes wet. Becomes saturated and fine at 32.5'. (WEATHERED TILL) Band of loose, gray, silty fine SAND, moist, from 37.5' to 38.0'. Trace coarse sand grains observed. Very stiff, olive brown, slightly sandy SILT, moist, from 38.0' to 38.5'. Rust banding throughout. Dense, olive brown, medium to coarse SAND with gravel, wet. Gravel is subrounded to subangular. Becomes silty fine SAND from 42.5' to 43.0. Rust banding observed. Boring terminated at 44 feet. No groundwater observed while conducting this exploratory boring (perched water possible at 32.5'). 6-9-11 3-5-7 5-11-13 9-26-28 7-10-17 SP SM SP BORING-DSM 2016-136.GPJ 5/2/17 FIGURE:PROJECT NO.:2016-136-21 Renton, Washington Renton Fire Statioin 15 BH-5 PAGE: 2 of 2(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-3 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)25 30 35 40 45 50 ELEVATION(feet)DATE COMPLETED: 3/29/2017 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" IC Continuous Flight HSA LOCATION: 46.1' East of West fence; 77.2' North of South fence DATE STARTED: 3/29/2017 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar >> SURFACE ELEVATION: Approx. 209 feet GS GS GS GS S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 S-9 S-10 Soft, dark brown, sandy SILT with organics, wet. (TOPSOIL) Medium stiff, olive brown, sandy SILT, wet. Rust bands observed throughout sample. (RECESSIONAL OUTWASH) Driller notes gravelly drilling action at 4.5'. Loose, dark yellowish brown, very sandy SILT, moist to wet. Trace organics. Rust bands observed. Loose, dark yellowish brown, slightly silty, fine to medium SAND, moist. One oxidation band at 8.0'. Becomes medium dense. Medium dense, grayish brown, slightly silty, fine to medium SAND, moist. Becomes lighter olive gray. Driller notes gravelly drilling action at 29'. Trace coarse sand in sampler tip (31.5'). Boring terminated at 31.5 feet. No groundwater observed while conducting this exploratory boring. 2-3-3 2-2-4 4-4-5 5-6-7 5-6-8 4-6-6 3-3-7 4-6-10 3-6-8 8-11-14 ML SM SP SM BORING-DSM 2016-136.GPJ 5/2/17 FIGURE:PROJECT NO.:2016-136-21 Renton, Washington Renton Fire Statioin 15 BH-6 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-4 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)0 5 10 15 20 25 30 35 ELEVATION(feet)DATE COMPLETED: 3/29/2017 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" IC Continuous Flight HSA LOCATION: 138.9' North of South fence; 35.0' West of East fence DATE STARTED: 3/29/2017 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar SURFACE ELEVATION: Approx. 214 feet S-1 S-2 S-3 S-4 GS + HYD GS + HYD GS + HYD SM ML SP SM 15 9 17 Medium dense, light olive brown, silty, fine to medium SAND, dry, scattered roots. (TOPSOIL) Medium dense, olive brown, sandy SILT, moist, trace coarse grains, trace fine to large gravel. (RECESSIONAL OUTWASH) Large boulder partially exposed in west wall of test pit. Medium dense, olive brown, slightly silty, fine to medium SAND, moist. Test pit terminated at 13' feet. Small scale pilot infiltration test performed at 7 feet. Renton, Washington 2016-136-21 FIGURE: SMART TP 2016-136.GPJ 8/31/17 Renton Fire Statioin 15 PAGE: 1 of 1 TP-2 LOG OF TEST PIT PROJECT NO.: and therefore may not necessarily be indicative of other times and/or locations. NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated A-5 EXCAVATION COMPANY: Kelly's Excavating EXCAVATING EQUIPMENT:SAMPLE NUMBERLOGGED BY: A. York DATE COMPLETED: 7/25/17 LOCATION: 120' N of S fence; 40' E of W fence.SYMBOLOTHER TESTSUSCS SOIL CLASSMOISTUE CONTENT (%)SAMPLE TYPEDEPTH (feet)0 5 10 15 DESCRIPTION TEST PIT PHOTO APPENDIX B LABORATORY TESTING Renton FS 15 - Final Report B-1 HWA GEOSCIENCES INC APPENDIX B LABORATORY TESTING Representative soil samples obtained from the explorations were returned to the HWA laboratory for further examination and testing. Laboratory tests were conducted on selected soil samples to characterize relevant engineering properties of the on-site materials. The laboratory testing program was performed in general accordance with appropriate ASTM Standards as outlined below. MOISTURE CONTENT: The moisture contents of selected soil samples were determined in general accordance with ASTM D 2216. The results are shown at the sampled intervals on the appropriate summary logs in Appendix A. PARTICLE SIZE ANALYSIS OF SOILS: The particle size distribution of selected soil samples was determined in general accordance with ASTM D422. The results are summarized on the attached Grain Size Distribution reports, Figures B-1 through B-7, which also provide information regarding the classification of the sample, and the moisture content at the time of testing. 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 Coarse #60#40 PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D422 50.4 40.5 12.6 #20 Fine Coarse SYMBOL Gravel % 3"1-1/2"PERCENT FINER BY WEIGHT#4 #200 1.0 2.1 7.0 Sand % (ML)Dark yellowish brown, sandy SILT (SM) Dark yellowish brown, silty SAND (SM) Dark yellowish brown, silty SAND Fines % 27 21 10 GRAIN SIZE IN MILLIMETERS 50 SAMPLE S-2 S-3 S-4 5.0 - 6.5 7.5 - 9.0 10.0 - 11.5 #10 48.6 57.4 80.4 30 CLASSIFICATION OF SOIL- ASTM D2487 Group Symbol and Name U.S. STANDARD SIEVE SIZES SAND CLAY BH-4 BH-4 BH-4 SILT 3/4" GRAVEL 0.05 5/8" 70 #100 0.5 50 Medium Fine 3/8" 5 PI 90 10 % MC LL PLDEPTH ( ft.) B-1 0.00050.005 2016-136-21PROJECT NO.: HWAGRSZ 2016-136.GPJ 8/31/17 FIGURE: Renton Fire Statioin 15 Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 Coarse #60#40 PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D422 13.0 14.2 29.9 #20 Fine Coarse SYMBOL Gravel % 3"1-1/2"PERCENT FINER BY WEIGHT#4 #200 8.0 Sand % (SM) Dark yellowish brown, silty SAND (SM) Dark yellowish brown, silty SAND (SM) Dark yellowish brown, silty SAND Fines % 20 17 22 GRAIN SIZE IN MILLIMETERS 50 SAMPLE S-6 S-7 S-1 15.0 - 16.5 17.5 - 19.0 2.5 - 4.0 #10 85.8 62.1 30 CLASSIFICATION OF SOIL- ASTM D2487 Group Symbol and Name U.S. STANDARD SIEVE SIZES SAND CLAY BH-4 BH-4 BH-5 SILT 3/4" GRAVEL 0.05 5/8" 70 #100 0.5 50 Medium Fine 3/8" 5 PI 90 10 % MC LL PLDEPTH ( ft.) B-2 0.00050.005 2016-136-21PROJECT NO.: HWAGRSZ 2016-136.GPJ 8/31/17 FIGURE: Renton Fire Statioin 15 Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 Coarse #60#40 PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D422 41.0 15.6 51.0 #20 Fine Coarse SYMBOL Gravel % 3"1-1/2"PERCENT FINER BY WEIGHT#4 #200 8.6 3.7 0.2 Sand % (SM) Dark yellowish brown, silty SAND (SM) Dark yellowish brown, silty SAND (ML) Dark yellowish brown, sandy SILT Fines % 21 13 26 GRAIN SIZE IN MILLIMETERS 50 SAMPLE S-2 S-3 S-4 5.0 - 6.5 7.5 - 9.0 10.0 - 11.5 #10 50.5 80.7 48.8 30 CLASSIFICATION OF SOIL- ASTM D2487 Group Symbol and Name U.S. STANDARD SIEVE SIZES SAND CLAY BH-5 BH-5 BH-5 SILT 3/4" GRAVEL 0.05 5/8" 70 #100 0.5 50 Medium Fine 3/8" 5 PI 90 10 % MC LL PLDEPTH ( ft.) B-3 0.00050.005 2016-136-21PROJECT NO.: HWAGRSZ 2016-136.GPJ 8/31/17 FIGURE: Renton Fire Statioin 15 Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 Coarse #60#40 PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D422 13.1 10.0 10.4 #20 Fine Coarse SYMBOL Gravel % 3"1-1/2"PERCENT FINER BY WEIGHT#4 #200 0.0 Sand % (SM) Dark brown, silty SAND (SP-SM) Olive brown, poorly graded SAND with silt (SP-SM) Olive brown, poorly graded SAND with silt Fines % 18 14 15 GRAIN SIZE IN MILLIMETERS 50 SAMPLE S-5 S-6 S-7 12.5 - 14.0 15.0 - 16.5 17.5 - 19.0 #10 86.8 89.6 30 CLASSIFICATION OF SOIL- ASTM D2487 Group Symbol and Name U.S. STANDARD SIEVE SIZES SAND CLAY BH-5 BH-5 BH-5 SILT 3/4" GRAVEL 0.05 5/8" 70 #100 0.5 50 Medium Fine 3/8" 5 PI 90 10 % MC LL PLDEPTH ( ft.) B-4 0.00050.005 2016-136-21PROJECT NO.: HWAGRSZ 2016-136.GPJ 8/31/17 FIGURE: Renton Fire Statioin 15 Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 Coarse #60#40 PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D422 8.9 62.4 12.4 #20 Fine Coarse SYMBOL Gravel % 3"1-1/2"PERCENT FINER BY WEIGHT#4 #200 0.5 0.2 Sand % (SP-SM) Grayish brown, poorly graded SAND with silt (ML) Dark yellowish brown, sandy SILT (SM) Dark yellowish brown, silty SAND Fines % 13 31 20 GRAIN SIZE IN MILLIMETERS 50 SAMPLE S-8 S-2 S-4 20.0 - 21.5 5.0 - 6.5 10.0 - 11.5 #10 37.1 87.4 30 CLASSIFICATION OF SOIL- ASTM D2487 Group Symbol and Name U.S. STANDARD SIEVE SIZES SAND CLAY BH-5 BH-6 BH-6 SILT 3/4" GRAVEL 0.05 5/8" 70 #100 0.5 50 Medium Fine 3/8" 5 PI 90 10 % MC LL PLDEPTH ( ft.) B-5 0.00050.005 2016-136-21PROJECT NO.: HWAGRSZ 2016-136.GPJ 8/31/17 FIGURE: Renton Fire Statioin 15 Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 Coarse #60#40 PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D422 9.0 9.1 61.4 #20 Fine Coarse SYMBOL Gravel % 3"1-1/2"PERCENT FINER BY WEIGHT#4 #200 0.1 0.7 Sand % (SP-SM) Grayish brown, poorly graded SAND with silt (SP-SM) Grayish brown, poorly graded SAND with silt (ML)Olive brown, sandy SILT Fines % 12 12 15 GRAIN SIZE IN MILLIMETERS 50 SAMPLE S-6 S-8 S-2 15.0 - 16.5 20.0 - 21.5 2.0 - 3.0 #10 91.0 90.8 37.9 30 CLASSIFICATION OF SOIL- ASTM D2487 Group Symbol and Name U.S. STANDARD SIEVE SIZES SAND CLAY BH-6 BH-6 TP-2 SILT 3/4" GRAVEL 0.05 5/8" 70 #100 0.5 50 Medium Fine 3/8" 5 PI 90 10 % MC LL PLDEPTH ( ft.) B-6 0.00050.005 2016-136-21PROJECT NO.: HWAGRSZ 2016-136.GPJ 8/31/17 FIGURE: Renton Fire Statioin 15 Renton, Washington 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.1110 Coarse #60#40 PARTICLE-SIZE ANALYSIS OF SOILS METHOD ASTM D422 7.6 9.5 #20 Fine Coarse SYMBOL Gravel % 3"1-1/2"PERCENT FINER BY WEIGHT#4 #200 0.0 Sand % (SP-SM) Olive brown, poorly graded SAND with silt (SP-SM) Light gray, poorly graded SAND with silt Fines % 9 17 GRAIN SIZE IN MILLIMETERS 50 SAMPLE S-3 S-4 7.0 - 8.0 8.0 - 9.0 #10 92.4 90.5 30 CLASSIFICATION OF SOIL- ASTM D2487 Group Symbol and Name U.S. STANDARD SIEVE SIZES SAND CLAY TP-2 TP-2 SILT 3/4" GRAVEL 0.05 5/8" 70 #100 0.5 50 Medium Fine 3/8" 5 PI 90 10 % MC LL PLDEPTH ( ft.) B-7 0.00050.005 2016-136-21PROJECT NO.: HWAGRSZ 2016-136.GPJ 8/31/17 FIGURE: Renton Fire Statioin 15 Renton, Washington APPENDIX C ADDITIONAL EXPLORATIONS A-12016-078-21 Kennydale 320 Pressure Zone Reservoir Renton, Washington LEGEND OF TERMS AND SYMBOLS USED ON EXPLORATION LOGS RELATIVE DENSITY OR CONSISTENCY VERSUS SPT N-VALUE COHESIONLESS SOILS Density Very Loose Loose Medium Dense Very Dense Dense N (blows/ft) 0 to 4 4 to 10 10 to 30 30 to 50 over 50 Approximate Relative Density(%) 0 - 15 15 - 35 35 - 65 65 - 85 85 - 100 COHESIVE SOILS Consistency Very Soft Soft Medium Stiff Stiff Very Stiff Hard N (blows/ft) 0 to 2 2 to 4 4 to 8 8 to 15 15 to 30 over 30 Approximate Undrained Shear Strength (psf) <250 250 - 500 500 - 1000 1000 - 2000 2000 - 4000 >4000 ASTM SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS Coarse Grained Soils Gravel and Gravelly Soils Clean Gravel (little or no fines) More than 50% of Coarse Fraction Retained on No. 4 Sieve Gravel with Fines (appreciable amount of fines) More than 50% Retained on No. 200 Sieve Size Sand and Sandy Soils Clean Sand (little or no fines) 50% or More of Coarse Fraction Passing No. 4 Sieve Sand with Fines (appreciable amount of fines) Fine Grained Soils Silt and Clay Liquid Limit Less than 50% 50% or More Passing No. 200 Sieve Size Silt and Clay Liquid Limit 50% or More Highly Organic Soils GROUP DESCRIPTIONS GW GP GM GC SW SP SM SC ML CL OL MH CH OH PT Well-graded GRAVEL Poorly-graded GRAVEL Silty GRAVEL Clayey GRAVEL Well-graded SAND Poorly-graded SAND Silty SAND Clayey SAND SILT Lean CLAY Organic SILT/Organic CLAY Elastic SILT Fat CLAY Organic SILT/Organic CLAY PEAT PZOLEGEND 2016-078.GPJ 11/22/16 PROJECT NO.:FIGURE: TEST SYMBOLS GS %F CN TX UC DS M PP TV CBR MD PID AL Grain Size Distribution Percent Fines Well Cap Concrete Seal 5 - Well Casing Bentonite Seal Groundwater Level (measured at time of drilling) Groundwater Level (measured in well after water level stabilized) Slotted Well Casing Consolidation Triaxial Compression Unconfined Compression Direct Shear Resilient Modulus Pocket Penetrometer Approx. Compressive Strength (tsf) Torvane Approximate Shear Strength (tsf) California Bearing Ratio Moisture/Density Relationship < Photoionization Device Reading Atterberg Limits:PL Plastic Limit LL Liquid Limit SAMPLE TYPE SYMBOLS 2.0" OD Split Spoon (SPT) (140 lb. hammer with 30 in. drop) Shelby Tube 3.0" OD Split Spoon with Brass Rings Small Bag Sample Large Bag (Bulk) Sample Core Run Non-standard Penetration Test (with split spoon sampler) COMPONENT PROPORTIONS Very (Clayey, Silty, Sandy, Gravelly) RANGE OF PROPORTIONDESCRIPTIVE TERMS Slightly (Clayey, Silty, Sandy) Sand Backfill GROUNDWATER WELL COMPLETIONS Locking Well Security Casing MOISTURE CONTENT DRY Absence of moisture, dusty, dry to the touch. Clean MOIST Damp but no visible water. WET Visible free water, usually soil is below water table. COMPONENT DEFINITIONS COMPONENT Boulders Cobbles Gravel Coarse gravel Fine gravel Sand Coarse sand Medium sand Fine sand Silt and Clay SIZE RANGE Larger than 12 in 3 in to 12 in 3 in to No 4 (4.5mm) 3 in to 3/4 in 3/4 in to No 4 (4.5mm) No. 4 (4.5 mm) to No. 200 (0.074 mm) No. 4 (4.5 mm) to No. 10 (2.0 mm) No. 10 (2.0 mm) to No. 40 (0.42 mm) No. 40 (0.42 mm) to No. 200 (0.074 mm) Smaller than No. 200 (0.074mm) NOTES: Soil classifications presented on exploration logs are based on visual and laboratory observation in general accordance with ASTM D 2487 and ASTM D 2488. Soil descriptions are presented in the following general order: Density/consistency, color, modifier (if any) GROUP NAME, additions to group name (if any), moisture content. Proportion, gradation, and angularity of constituents, additional comments. (GEOLOGIC INTERPRETATION) Please refer to the discussion in the report text as well as the exploration logs for a more complete description of subsurface conditions. 12% 12 - 30% 30 - 50% 5% Clayey, Silty, Sandy, Gravelly S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 S-9 S-10 GS GS GS GS ML SM SP 1-2-2 3-7-6 4-6-7 5-7-8 4-5-9 3-5-9 10-19-24 5-7-14 6-12-14 4-9-13 Soft, brown, organic, sandy SILT, moist. (TOPSOIL) Loose, light olive brown, very sandy SILT, moist. Trace coarse sand. Scattered roots and rust mottling. (RECESSIONAL OUTWASH) Alternating bands of medium dense, olive gray and olive brown, silty, fine to medium SAND, moist. Bands are up to 1" in thickness. Trace roots. Medium dense, olive brown, slightly silty, fine to medium SAND, moist. Rust band observed at 8.1'. Medium dense, olive brown, very silty, fine to medium SAND, moist. Band of olive brown, silty fine sand from 12.9'-13.4'. Medium dense, olive gray, clean, fine to medium SAND, moist. Bands of olive brown, silty fine sand up to 2" thick throughout sample. Dense, gray, clean, fine to coarse SAND, moist. Becomes more dry with fine gravels increasing in abundance starting at 18.6'. Possibly overstated blow counts due to gravel in sampler. Medium dense, olive gray, fine to medium SAND, moist. Trace coarse sand and fine gravel. Trace rust mottling. Medium dense, gray, clean, fine to coarse SAND with fine gravel, moist. Medium dense, gray, clean, fine to medium SAND, moist. Trace fine gravel. One bad of coarse sand from 28.7' to 28.8'. 0 20 40 60 80 100 Water Content (%) Plastic Limit (140 lb. weight, 30" drop) Blows per foot (blows/6 inches)USCS SOIL CLASSDESCRIPTION SAMPLE TYPESAMPLE NUMBERPEN. RESISTANCEOTHER TESTSPIEZOMETERStandard Penetration Test A-2SYMBOLSCHEMATIC01020304050 Liquid Limit BORING: BH-1 PAGE: 1 of 2 Water Content (%) Natural Water ContentNOTE: This log of subsurface conditions applies only at the specified location and on the date indicated and therefore may not necessarily be indicative of other times and/or locations. PZO-DSM 2016-078.GPJ 1/3/17 FIGURE:PROJECT NO.:2016-078-21 Renton, Washington Kennydale 320 Pressure Zone ReservoirDEPTH(feet)0 5 10 15 20 25 30 ELEVATION(feet)DATE COMPLETED: 11/10/2016 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" ID continuous flight HSA LOCATION: 55.2' west of eastern fence line; 54.7' south of northern fence line DATE STARTED: 11/10/2016 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar S-11 S-12 S-13 S-14 S-15 SM 10-15-18 10-12-16 15-28-27 50/6" 12-37-50/4" Dense, olive gray, slightly silty, fine to medium SAND, moist. Medium dense, olive gray, clean, fine to medium SAND, moist. Becomes fine sand at 38.5'. Driller notes hard drilling at 40'. Very dense, olive brown, silty, fine to medium SAND with minor fine gravel, moist. Faint rust mottling. (GLACIAL TILL) Very dense, olive brown, silty, fine to medium SAND, moist. Very dense, olive brown, silty, fine to medium SAND with gravel, moist. Boring terminated at 51.3 feet. No groundwater observed while conducting this exploratory boring. Piezo well installed. Well tag #BIZ317. Groundwater observed at 46.6 feet bgs on 11/11/2016. 0 20 40 60 80 100 Water Content (%) Plastic Limit (140 lb. weight, 30" drop) Blows per foot (blows/6 inches)USCS SOIL CLASSDESCRIPTION SAMPLE TYPESAMPLE NUMBERPEN. RESISTANCEOTHER TESTSPIEZOMETERStandard Penetration Test A-2SYMBOLSCHEMATIC01020304050 Liquid Limit BORING: BH-1 PAGE: 2 of 2 Water Content (%) Natural Water ContentNOTE: This log of subsurface conditions applies only at the specified location and on the date indicated and therefore may not necessarily be indicative of other times and/or locations. PZO-DSM 2016-078.GPJ 1/3/17 FIGURE:PROJECT NO.:2016-078-21 Renton, Washington Kennydale 320 Pressure Zone ReservoirDEPTH(feet)30 35 40 45 50 55 60 ELEVATION(feet)DATE COMPLETED: 11/10/2016 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" ID continuous flight HSA LOCATION: 55.2' west of eastern fence line; 54.7' south of northern fence line DATE STARTED: 11/10/2016 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar >> >> >> GS GS GS GS %F S-1 S-2 S-3 S-4A S-4B S-5 S-6 S-7A S-7B S-8 S-9 S-10 Soft, brown, organic, sandy SILT, moist. (TOPSOIL) Medium dense, light olive brown, very sandy SILT, moist. Trace coarse sand and fine gravel. Roots. Rust mottling around gravels. (RECESSIONAL OUTWASH) Medium dense, olive brown, very silty, fine to medium SAND, moist. Rust mottling and trace roots throughout sample. Scattered lenses of olive gray clean fine to medium sand. Medium dense, olive brown, silty, fine to medium SAND, dry/moist. Trace roots. Medium dense, olive brown, silty, fine to medium SAND, moist. Becomes clean at 11.0'. Medium dense, olive gray, fine to medium, poorly graded SAND, with silt, moist. Medium dense, olive gray, fine to medium SAND with trace fine gravel and silt, moist. One silty fine sand lens from 16.0 to 16.2'. Medium dense, olive brown, sandy SILT, moist. Thinly bedded. Medium dense, olive gray, clean, fine to coarse SAND with fine gravel, moist. Grain size increases with depth. Medium dense, olive gray, clean, fine to medium SAND, moist. Trace coarse sand and fine gravel. Poor recovery during sample. Medium dense, gray, fine to medium SAND with fine gravel, moist. Gravel increases in abundance with depth. 2-5-14 7-9-9 7-9-8 6-7-9 4-7-7 5-5-9 5-7-14 4-6-11 5-8-11 6-11-15 ML SM SP SM ML SP BORING-DSM 2016-078.GPJ 1/3/17 FIGURE:PROJECT NO.:2016-078-21 Renton, Washington Kennydale 320 Pressure Zone Reservoir BH-2 PAGE: 1 of 3(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-3 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)0 5 10 15 20 25 30 ELEVATION(feet)DATE COMPLETED: 11/9/2016 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" ID continuous flight HSA LOCATION: 71.6' west of eastern fence line; 72.0' south of northern fence line DATE STARTED: 11/9/2016 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar S-11 S-12 S-13A S-13B S-14 S-15 S-16 Dense, olive gray, clean, fine to coarse SAND, moist. Becomes fine to medium. Becomes wet. Dense, olive brown, silty SAND, moist. Trace fine gravel. More gravel in sampler tip. (GLACIAL TILL) Drillers report gravelly drilling at 45' Hard, olive brown, fine sandy SILT, moist. Rust mottling. Trace coarse sand. Very dense, gray, silty SAND with gravel, moist. Very dense, gray, silty, fine SAND with trace coarse sand and fine gravel, moist. Becomes olive brown from 53.5' to 54'. Very dense, gray, silty SAND with gravel, moist. Weathered sandstone in sampler from 57.5' to 58'. 10-17-27 9-14-16 13-14-22 11-25-43 21-32-50/6" 33-50/3" SP SM SM BORING-DSM 2016-078.GPJ 1/3/17 FIGURE:PROJECT NO.:2016-078-21 Renton, Washington Kennydale 320 Pressure Zone Reservoir BH-2 PAGE: 2 of 3(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-3 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)30 35 40 45 50 55 60 ELEVATION(feet)DATE COMPLETED: 11/9/2016 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" ID continuous flight HSA LOCATION: 71.6' west of eastern fence line; 72.0' south of northern fence line DATE STARTED: 11/9/2016 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar >> >> >> S-17 S-18 S-19 Very dense, olive gray to gray, silty, fine SAND with gravel, moist. Trace coarse sand above sampler tip. Hard, olive brown, sandy SILT, moist. Rust at lower contact. Drillers noted earier drilling at 64'. (ADVANCE OUTWASH) Very dense, gray, silty, fine SAND with trace gravel, moist. Angled clean sand layer at 68.5' Very dense, gray, gravelly SAND with silt, wet. Poor recovery. Boring terminated at 73 feet. Groundwater observed at 43.5 feet while conducting this exploratory boring. 50/6" 14-21-28 50/6" SM SP BORING-DSM 2016-078.GPJ 1/3/17 FIGURE:PROJECT NO.:2016-078-21 Renton, Washington Kennydale 320 Pressure Zone Reservoir BH-2 PAGE: 3 of 3(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-3 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)60 65 70 75 80 85 90 ELEVATION(feet)DATE COMPLETED: 11/9/2016 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" ID continuous flight HSA LOCATION: 71.6' west of eastern fence line; 72.0' south of northern fence line DATE STARTED: 11/9/2016 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar >> >> GS GS GS GS S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 S-9 Soft, dark brown, organic, sandy SILT, moist. Roots. (TOPSOIL) Loose, olive brown, very silty, fine to medium SAND, moist. Trace fine gravels. Rust mottling throughout. Roots. (RECESSIONAL OUTWASH) Medium dense, olive brown, silty, fine to medium SAND, moist. Roots, scattered rust bands. Medium dense, olive gray, clean SAND, moist. Trace silt. Thinly bedded. Scattered rust bands. Becomes slightlty silty. Bedding becomes massive. Medium dense, olive gray, silty, fine to medium SAND, moist. Scattered rust mottling observed. Silt band observed from 21'-21.3'. Some fine gravels from 21.3'-21.5'. Boring terminated at 21.5 feet. No groundwater observed while conducting this exploratory boring. 1-2-1 2-4-5 4-7-10 5-6-7 5-7-8 4-5-6 4-7-10 4-5-7 4-6-8 SM SP SM SM BORING-DSM 2016-078.GPJ 1/3/17 FIGURE:PROJECT NO.:2016-078-21 Renton, Washington Kennydale 320 Pressure Zone Reservoir BH-3 PAGE: 1 of 1(blows/6 inches)GROUNDWATERPEN. RESISTANCELiquid Limit (140 lb. weight, 30" drop) Blows per foot A-4 Standard Penetration Test NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated DESCRIPTION OTHER TESTSPlastic Limit BORING: and therefore may not necessarily be indicative of other times and/or locations.SYMBOL0 10 20 30 40 50 0 20 40 60 80 100SAMPLE TYPESAMPLE NUMBERNatural Water ContentUSCS SOIL CLASSWater Content (%)DEPTH(feet)0 5 10 15 20 25 30 ELEVATION(feet)DATE COMPLETED: 11/9/2016 DRILLING COMPANY: Environmental Drilling Inc. DRILLING METHOD: B-61 Truck Rig with 4.25" ID continuous flight HSA LOCATION: 43.5' east of western fence line; 75.9' south of northern fence line DATE STARTED: 11/9/2016 SAMPLING METHOD: SPT with auto-hammer LOGGED BY: B. Salazar S-1 S-2 S-3 S-4 GS+HYD GS+HYD SM SM SP SM 10 10 Medium dense, light olive brown, silty, fine SAND, dry to moist, trace coarse sand, scattered roots. (RECESSIONAL OUTWASH) Stiff, olive brown, very silty, fine SAND, grades to very silty, fine SAND, moist, non-plastic, with scattered fine to large gravel and cobbles. Medium dense, olive brown, slightly silty, fine to medium SAND, moist, olive greyish brown at 8'. Medium dense, olive greyish brown, slightly silty to clean, fine to medium SAND, moist, some caving at 13'. Renton, Washington 2016-078-21 FIGURE: SMART TP 2016-078.GPJ 8/31/17 Kennydale 320 Pressure Zone Reservoir PAGE: 1 of 2 TP-1 LOG OF TEST PIT PROJECT NO.: and therefore may not necessarily be indicative of other times and/or locations. NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated A-5 EXCAVATION COMPANY: EXCAVATING EQUIPMENT:SAMPLE NUMBERLOGGED BY: A. York DATE COMPLETED: 7/25/17 LOCATION: 75' S of N fence; 40' E of W fence SYMBOLOTHER TESTSUSCS SOIL CLASSMOISTUE CONTENT (%)SAMPLE TYPEDEPTH (feet)0 5 10 15 DESCRIPTION TEST PIT PHOTO S-5 GS+HYDSP SM 7 Medium dense, olive greyish brown, slightly silty to clean, fine to medium SAND, moist. Test pit terminated at 19 feet. Pilot infiltration test performed at 16 feet. Renton, Washington 2016-078-21 FIGURE: SMART TP 2016-078.GPJ 8/31/17 Kennydale 320 Pressure Zone Reservoir PAGE: 2 of 2 TP-1 LOG OF TEST PIT PROJECT NO.: and therefore may not necessarily be indicative of other times and/or locations. NOTE: This log of subsurface conditions applies only at the specified location and on the date indicated A-5 EXCAVATION COMPANY: EXCAVATING EQUIPMENT:SAMPLE NUMBERLOGGED BY: A. York DATE COMPLETED: 7/25/17 LOCATION: 75' S of N fence; 40' E of W fence SYMBOLOTHER TESTSUSCS SOIL CLASSMOISTUE CONTENT (%)SAMPLE TYPEDEPTH (feet)15 20 25 30 DESCRIPTION TEST PIT PHOTO