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HomeMy WebLinkAboutRS_Geotechnical_Report_2018.pdfREPORT COVER PAGE RED Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 Renton, King County, Washington June 21, 2018 Terracon Project No. 81185084 Prepared for: Chick-fil-A, Inc. Irvine, California Prepared by: Terracon Consultants, Inc. Mountlake Terrace, WA Terracon Consultants, Inc.21905 64th Avenue West Mountlake Terrace, Washington 98043 P (425) 771 3304 F (425) 771 3549 terracon.com REPORT COVER LETTER TO SIGN June 21, 2018 Chick-fil-A, Inc. 15635 Alton Parkway Suite 350 Irvine, California 30349 Attn: Mr. Don Ikeler P:[404] 765 8000 Re: Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 361 Rainier Avenue South Renton, King County, Washington Terracon Project No. 81185084 Dear Mr. Ikeler: We have completed the Geotechnical Engineering services for the above referenced project. This study was performed in general accordance with Terracon Master Services Task Order dated April 24, 2018. This report presents the findings of the subsurface exploration and provides geotechnical recommendations concerning earthwork and the design and construction of foundations, floor slabs, and pavements for the proposed project. We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report, or if we may be of further service, please contact us. Sincerely, Terracon Consultants, Inc. Lauren Phillips, EIT David A. Baska, Ph.D., P.E. Geotechnical Field Engineer Senior Engineering Consultant National Account Manager: Romeo deLeon, Senior Principal Responsive ■Resourceful ■Reliable REPORT TOPICS REPORT TOPICS REPORT SUMMARY ....................................................................................................... i INTRODUCTION ............................................................................................................. 1 SITE CONDITIONS ......................................................................................................... 1 PROJECT DESCRIPTION .............................................................................................. 2 GEOTECHNICAL CHARACTERIZATION ...................................................................... 3 GEOTECHNICAL OVERVIEW ....................................................................................... 4 EARTHWORK................................................................................................................. 5 SHALLOW FOUNDATIONS ........................................................................................... 9 GROUND IMPROVEMENT ........................................................................................... 11 SPECIALTY FOUNDATIONS ....................................................................................... 12 SEISMIC CONSIDERATIONS ...................................................................................... 13 LIQUEFACTION ........................................................................................................... 14 FLOOR SLABS............................................................................................................. 15 PAVEMENTS ................................................................................................................ 16 GENERAL COMMENTS ............................................................................................... 20 Note: This report was originally delivered in a web-based format.Orange Bold text in the report indicates a referenced section heading. The PDF version also includes hyperlinks which direct the reader to that section and clicking on the logo will bring you back to this page. For more interactive features, please view your project online at client.terracon.com . ATTACHMENTS EXPLORATION AND TESTING PROCEDURES SITE LOCATION AND EXPLORATION PLANS EXPLORATION RESULTS (Boring Logs and Laboratory Data) SUPPORTING INFORMATION (General Notes and Unified Soil Classification System) Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable i REPORT SUMMARY Topic 1 Overview Statement 2 Project Description Approximately 4,696 square foot structure Max. Column loads: 50 kips, Max. Wall loads: 2 kips per lineal foot Finished floor elevation: assumed to be at or near existing site grades Excavations to include demolition of old building and parking area, and new foundation construction Expected traffic for pavement areas: ■300 autos/light trucks per day ■Up to 5 medium-duty delivery/trash trucks and 1 Tractor-trailer per week Geotechnical Characterization Areas of existing fill extending to up to 3 feet below ground surface, underlain by alluvial deposits composed primarily of silt, sand, and gravel that are very loose in the top 10 feet and become denser with depth. Groundwater encountered at a depth ranging from 8 to 12 feet in borings B-1 and B-3. Earthwork Options for floor slab subgrade preparation & risk of post-construction movement: ■Low risk: structural floor slab supported on small diameter piles. ■Medium risk (Terracon recommendation): slab on grade with ground improvement through the use of aggregate piers. Minimal settlement may occur. Any material proposed to be used for engineered fill should be tested & approved Fines are sensitive to moisture variation and movement. Shallow Foundations Shallow foundations will be sufficient if combined with ground improvement. Small diameter piles may also be used as an alternative to shallow foundations and ground improvement. Preliminary allowable bearing pressure = 4,000 lbs/sq ft Expected settlements: < 1 inch total, < 2/3 inch differential Detect and remove zones of unsuitable soils as noted in Earthwork Lateral Earth Pressure Recommendations No retaining walls exist on or are proposed for this site. Pavements For subgrade prepared as noted in Earthwork with 2 feet of over-excavation,we have provided CFA’s standard pavement sections. General Comments This section contains important information about the limitations of this geotechnical engineering report. 1.If the reader is reviewing this report as a pdf, the topics above can be used to access the appropriate section of the report by simply clicking on the topic itself. 2.This summary is for convenience only. It should be used in conjunction with the entire report for design purposes. Responsive ■Resourceful ■Reliable 1 INTRODUCTION Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 361 Rainier Avenue South Renton, King County, Washington Terracon Project No. 81185084 June 21, 2018 INTRODUCTION This report presents the results of our subsurface exploration and geotechnical engineering services performed for the proposed Chick-fil-A restaurant #04249 to be located at 361 Rainier Avenue South in Renton, King County, Washington. The purpose of these services is to provide information and geotechnical engineering recommendations relative to: ■Subsurface soil conditions ■Foundation design and construction ■Groundwater conditions ■Floor slab design and construction ■Site preparation and earthwork ■Seismic site classification per IBC ■Demolition considerations ■Pavement design and construction ■Excavation considerations The geotechnical engineering scope of services for this project included the advancement of 8 test borings to depths ranging from approximately 6 ½ to 51 ½ feet below existing site grades. Maps showing the site and boring locations are shown in the Site Location and Exploration Plan sections, respectively. The results of the laboratory testing performed on soil samples obtained from the site during the field exploration are included on the boring logs and as separate graphs in the Exploration Results section of this report. SITE CONDITIONS The following description of site conditions is derived from our site visit in association with the field exploration and our review of publicly available geologic and topographic maps. Item Description Parcel Information The project is located at 361 Rainier Avenue South in Renton, King County, Washington. Latitude: 47° 3' 40.82" N, Longitude: 122° 45' 51.228" W. (See Site Location) Existing Improvements Existing asphalt parking lot and grass area, existing building formerly occupied by Diamond Lil’s Card Casino. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 2 Item Description Current Ground Cover Asphalt paved parking lot and unpaved grass area. Existing Topography Based on review of USGS quadrangle maps and information from Google Earth Pro, grade change of about 29 feet (NE corner of site) to 26 feet (SW corner of site). Within the proposed building area, grade change of about 28 feet (South end of building) to 27 feet (North end of building) is expected. Site History From review of historical aerial photos and city tax records, it appears the existing casino has been on-site since 1964. Another building was located on what is currently the unpaved grassy area and was demolished in the late 2000’s. Additional site history can be found in the Phase 1 assessment Terracon completed for this site, Terracon Report No. 81187027. PROJECT DESCRIPTION Our final understanding of the project conditions is as follows: Item Description Information Provided Preliminary Site Plan with seal dated April 16, 2018 Project Description The project includes a single-story Chick-fil-A restaurant building in the southeast corner of the approximate 1-acre site with associated parking and drive through improvements. Proposed Structure A single-story building with a footprint of about 4,696 square feet. The building will be slab-on-grade (non-basement). Building Construction Details not provided but understood to be concrete masonry units (CMU) with steel and/or wood framing with concrete foundations. Finished Floor Elevation Assumed to be at or near existing site grades. Maximum Loads ■Column Loads: 50 kips ■Walls Loads: 2 kips per lineal foot ■Floor slab Load: 125 psf Grading/Slopes Grading plan not provided at the time of this proposal. Free-Standing Retaining Walls Retaining walls are not expected to be constructed as part of site development to achieve final grades. Pavements Paved drive and parking to accommodate up to 36 vehicles is planned. No specific traffic information has been provided to us. Without this information, we plan to use the following traffic volumes for design of the pavement: Autos/Light Trucks: 300 vehicles per day Light Delivery and Trash Collection Vehicles: 5 vehicles per week Tractor-trailer trucks: Less than 1 vehicle per week. The pavement design period is 20 years. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 3 GEOTECHNICAL CHARACTERIZATION Subsurface Profile We have developed a general characterization of the subsurface soil and groundwater conditions based upon our review of the data and our understanding of the geologic setting and planned construction. The following table provides our geotechnical characterization. The geotechnical characterization forms the basis of our geotechnical calculations and evaluation of site preparation, foundation options and pavement options. As noted in General Comments, the characterization is based upon widely spaced exploration points across the site, and variations are likely. Stratum Approximate Depth to Bottom of Stratum (feet)Material Description Consistency/Density Surface ½ to 1 Asphalt / Concrete Pavement N/A Surface 1 to 2 Fill: Silty Gravel with Sand N/A 1 10 to 12 Alluvial Deposits: Silt, Silt with sand, Sand with silt, and Sand Very loose/soft 2 12 to 19 ½Alluvial Deposits: Sand, Sand with silt, and Silty Sand Loose 3 Undetermined1 Alluvial Deposits: Sandy Gravel Medium dense to dense 1.Borings terminated within this stratum at the planned depth of approximately 51 ½ feet. Conditions encountered at each boring location are indicated on the individual boring logs shown in the Exploration Results section and are attached to this report. Stratification boundaries on the boring logs represent the approximate location of changes in native soil types; in situ, the transition between materials may be gradual. Groundwater Conditions The boreholes were observed while drilling and after completion for the presence and level of groundwater. The water levels observed in the boreholes can be found on the boring logs in Exploration Results, and are summarized below. Boring Number Approximate Depth to Groundwater while Drilling (feet)1 B-1 8 B-3 12 Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 4 Groundwater was not observed in the remaining borings while drilling, or for the short duration the borings could remain open. However, this does not necessarily mean the borings terminated above groundwater, or the water levels summarized above are stable groundwater levels. Furthermore, the mud-rotary method used on boring B-4 does not allow for an accurate water level measurement to be taken. Groundwater level fluctuations occur due to seasonal variations in the amount of rainfall, runoff and other factors not evident at the time the borings were performed. Therefore, groundwater levels during construction or at other times in the life of the structure may be higher or lower than the levels indicated on the boring logs. The possibility of groundwater level fluctuations should be considered when developing the design and construction plans for the project. GEOTECHNICAL OVERVIEW Much of the site is covered by asphalt overlying approximately 1 to 2 feet of fill. On the south end of the site there is an additional layer of asphalt underlying the surface layer. Below the surface soils, an approximate 10 to 12-foot layer of very loose silt and sand combined with the high water table increase the susceptibility to static settlements and liquefaction in the event of an earthquake. These conditions would not provide adequate support for building loads and settlements due to liquefaction would likely be several inches. To address these concerns we recommend that the building be supported on small diameter (pin) piles or that ground improvement such as aggregate piers be utilized to improve foundation soils. The soils which form the bearing stratum for ground improvement or specialty foundations are dense to medium dense sandy gravels located approximately 20 feet below the ground surface. The Ground Improvement and Specialty Foundations section of this report provide design parameters for the two foundation support options. The near-surface silty gravel with sand and silt with sand could become unstable with typical earthwork and construction traffic, especially after precipitation events. Effective drainage should be established early in the construction sequence and maintained after construction to avoid potential issues. If possible, the grading should be performed during the warmer and drier time of the year. If grading is performed during the winter months, the risk for possible overexcavation and replacement of unstable subgrade will increase. Additional site preparation recommendations including subgrade improvement and fill placement are provided in the Earthwork section. The Floor Slabs section addresses structural slab and slab-on-grade support of the building. Options for floor slab subgrade preparation and risk of post-construction movement include: ■Low risk: Install small diameter piles and support structural slab on piles. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 5 ■Medium risk (Terracon recommendation): Utilize ground improvement, such as aggregate piers, and install a slab-on-grade. This will help provide a uniform layer below the slab but has a slight risk of settlement. A combined rigid/flexible pavement system is recommended for this site. The Pavements section addresses the design of pavement systems and subgrade preparation options and recommendations. The General Comments section provides an understanding of the report limitations. EARTHWORK Earthwork will include demolition of existing structures, excavations and fill placement. The following sections provide recommendations for use in the preparation of specifications for the work. Recommendations include critical quality criteria as necessary to render the site in the state considered in our geotechnical engineering evaluation for foundations, floor slabs, and pavements. Site Preparation Prior to placing fill, existing vegetation, root mat, and existing pavements should be removed. Complete stripping of the topsoil should be performed in the proposed building and parking/driveway areas. Given the wet and soft subgrade anticipated following removal of existing pavements and fills, haul roads and other traffic areas may require stabilization with quarry spalls and possibly a geotextile separation layer. Following removal of unsuitable soils and selected overexcavation, the subgrade should be proof- rolled with an adequately loaded vehicle such as a fully loaded tandem axle dump truck. The proof-rolling should be performed under the observation of the Geotechnical Engineer. Areas excessively deflecting under the proof-roll should be delineated and subsequently addressed by the Geotechnical Engineer. Such areas should either be removed or replaced by tested and approved structural fill. Excessively wet or dry material should either be removed or moisture conditioned and recompacted. In pavement areas, the following procedure should be followed. Over-excavation should extend to 2 feet below the bottom of the pavement section (i.e., asphalt surface course and aggregate base). Geotextile, such as Mirafi 500x, should be placed directly on the subgrade to provide separation between the soft subgrade and the structural fill. Above the geotextile, place and compact 2 feet of structural fill in two lifts. The first lift should be 18 inches thick followed by a 6 inch thick lift. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 6 Given the wet, very soft and loose consistency of the material underlying the structural fill, dynamic compaction may lead to excessive movements or “pumping” of the subgrade. A Geotechnical Engineer should be present to observe compaction and if movement in the native soils below the structural fill is observed, static compaction techniques should be employed. Fill Material Types Some onsite soils may be suitable for reuse however the soils would need to be assessed by a Geotechnical Engineer at the time of construction. The gradation and moisture content will dictate the acceptability of the onsite soils for reuse and the contractor may find it more expedient and economical to only use imported fill. Fill required to achieve design grade should meet the following material property requirements: Soil Type 1 USCS Classification Acceptable Parameters (for Structural Fill) On-site soil 2 GM, SP, SP-SM, ML Near surface soil generally appear to consist of silty gravel with sand. Soils with a greater fraction of fines content will be more sensitive to changes in moisture and may not be practical for re-use as structural fill if the moisture content deviates more than 2 percent from optimum.3 A Terracon representative should be present to assess suitability of on-site soils for re-use as fill. Select Granular Fill 4 SP, SW, GW Recommended for use in wet weather conditions. Select fill can generally be placed and compacted in a wider variety of weather conditions than Common import fill. Common Fill5 -- Generally consists of lesser quality, more moisture-sensitive soils that can be compacted to a firm and non-yielding condition if near the optimum moisture content. 1. Structural fill should consist of approved materials that are free of organics or debris. Frozen material should not be used, and fill should not be placed on frozen subgrade. Maximum particle diameter should be 3 inches. Each proposed fill material should be sampled and evaluated by the geotechnical engineer prior to its delivery and/or use. 2. Sorting of topsoil and on-site soils containing debris, organics, etc., will be necessary. Delineation of unsuitable on-site soils should be performed in the field by a Terracon representative. Moisture conditioning (i.e., drying) of the on-site soils will be necessary to facilitate compaction. 3. After excavation, we recommend that any stockpiled soil intended to be reused as structural fill be covered with plastic sheeting to prevent deviations from the natural in-situ moisture content of the soil. 4. Select fill should meet the general requirements of Section 9-03.14(1), Gravel Borrow, as presented in the Washington State Department of Transportation (WSDOT) Standard Specifications for Road, Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 7 Soil Type 1 USCS Classification Acceptable Parameters (for Structural Fill) Bridge, and Municipal Construction. The percent passing the US No. 200 mesh sieve should, however, be modified from the WSDOT specification to a maximum of 5 percent by weight passing the US No. 200 mesh sieve 5. Common engineered fill should meet the requirements of Section 9-03.14(3), Common Borrow, as presented in the WSDOT Standard Specifications for Road, Bridge, and Municipal Construction Fill Compaction Requirements Structural and general fill should meet the following compaction requirements. Item Description Fill Lift Thickness 1 10 inches or less in loose thickness. See specific recommendations for Pavement sections in Site Preparation Compaction Requirements 2, 3 All locations 95% of the material’s modified Proctor maximum dry density (ASTM D 1557). Moisture Content Within the range of +/- 2 percent of the optimum moisture content. 1. Thinner lifts may be required in confined areas or within excavations, or when hand-operated compaction equipment is used. 2. We recommend structural fill be tested for moisture content and compaction during placement. Bottoms of all excavations should be compacted with lightweight, remote equipment such as a small rolling drum compactor, to minimize disturbance of the wetter soils. Should the results of the in- place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved. Utility Trench Backfill Utility trenching should conform to all applicable federal, state, and local regulations, such as OSHA and WISHA, for open excavations. All trenches should be wide enough to allow for compaction around the haunches of the pipe, or material such as pea gravel (provided this is allowed by the pipe manufacturer) should be used below the spring line of the pipes to eliminate the need for mechanical compaction in this portion of the trenches. We recommend that utility trench excavations be completed using a smooth excavation bucket (without teeth) to reduce the potential for subgrade disturbance. If water is encountered in the excavations, it should be removed prior to fill placement. Materials, placement and compaction of utility trench backfill should be in accordance with the recommendations presented in Fill Material Types and Fill Compaction Requirements Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 8 sections of this report. In our opinion, the initial lift thickness should not exceed one foot unless recommended by the manufacturer to protect utilities from damage by compacting equipment. Light, hand-operated compaction equipment in conjunction with thinner fill lift thicknesses may be utilized on backfill placed above utilities if damage resulting from heavier compaction equipment is of concern. Grading and Drainage All grades must provide effective drainage away from the building during and after construction and should be maintained throughout the life of the structure. Water retained next to the building can result in soil movements greater than those discussed in this report. Greater movements can result in unacceptable differential floor slab and/or foundation movements, cracked slabs and walls, and roof leaks. The roof should have gutters/drains with downspouts that discharge onto splash blocks at a distance of at least 10 feet from the building. Exposed ground should be sloped and maintained at a minimum 5 percent away from the building for at least 10 feet beyond the perimeter of the building. Locally, flatter grades may be necessary to transition ADA access requirements for flatwork. After building construction and landscaping, final grades should be verified to document effective drainage has been achieved. Grades around the structure should also be periodically inspected and adjusted as necessary as part of the structure’s maintenance program. Where paving or flatwork abuts the structure a maintenance program should be established to effectively seal and maintain joints and prevent surface water infiltration. Earthwork Construction Considerations Shallow excavations, for the proposed structure, are anticipated to be accomplished with conventional construction equipment. Upon completion of filling and grading, care should be taken to maintain the subgrade water content prior to construction of floor slabs. Construction traffic over the completed subgrades should be avoided. The site should also be graded to prevent ponding of surface water on the prepared subgrades or in excavations. Water collecting over, or adjacent to, construction areas should be removed. If the subgrade freezes, desiccates, saturates, or is disturbed, the affected material should be removed, or the materials should be scarified, moisture conditioned, and recompacted, prior to floor slab construction. We recommend that the earthwork portion of this project be completed during extended periods of dry weather, if possible. If earthwork is completed during the wet season, it may be necessary to take extra precautionary measures to protect subgrade soils. Wet season earthwork may require additional mitigating measures beyond that which would be expected during the drier months. Once subgrades are established, it may be necessary to protect the exposed subgrade soils from construction traffic. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 9 As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part 1926, Subpart P, “Excavations” and its appendices, and in accordance with any applicable local, and/or state regulations. Construction site safety is the sole responsibility of the contractor who controls the means, methods, and sequencing of construction operations. Under no circumstances shall the information provided herein be interpreted to mean Terracon is assuming responsibility for construction site safety, or the contractor's activities; such responsibility shall neither be implied nor inferred. Construction Observation and Testing The earthwork efforts should be monitored under the observation of the Geotechnical Engineer. Monitoring should include documentation of adequate removal of any vegetation, existing fill and top soil, proofrolling and mitigation of areas delineated by the proofroll to require mitigation. Each lift of compacted fill should be tested, evaluated, and reworked as necessary until approved by the Geotechnical Engineer prior to placement of additional lifts. In areas of foundation excavations, the bearing subgrade should be observed by the Geotechnical Engineer. In the event that unanticipated conditions are encountered, the Geotechnical Engineer should recommend mitigation options. In addition to the documentation of the essential parameters necessary for construction, the continuation of the Geotechnical Engineer into the construction phase of the project provides the continuity to maintain the Geotechnical Engineer’s evaluation of subsurface conditions, including assessing variations and associated design changes. SHALLOW FOUNDATIONS If the site has been prepared in accordance with the requirements noted in Earthwork, the following design parameters are applicable for shallow foundations. Design Parameters – Compressive Loads Description Column Wall Net allowable soil bearing pressure 1 4,000 psf2 4,000 psf2 Minimum dimensions 24 inches 18 inches Minimum embedment 3 18 inches 18 inches Estimated total settlement 4 < 1 inch < 1 inch Estimated differential settlement 4 2/3-inch between columns 2/3-inch over 40 feet Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 10 Description Column Wall Ultimate Equivalent fluid pressure 5 400 pcf Ultimate coefficient of sliding friction 5 0.45 1. The recommended net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the footing base elevation. Assumes any unsuitable fill or soft soils, if encountered, will be undercut and replaced with engineered fill. Disturbance of the wetter soils may require the need for a granular stabilization layer for an appropriate working surface. Terracon should be consulted if this issue becomes apparent. 2. Final soil bearing pressures should be developed by the specialty contractor that designs the ground improvement. 3. For perimeter footings and footings in unheated areas. For frost protection and to reduce the effects of seasonal moisture variations in the subgrade soils. If construction extends into freezing weather, we recommend that either all footings extend to frost depth (as measured from adjacent grade at the time of construction) or that the foundations be protected from the elements by straw, frost blankets, or similar means. 4. The foundation settlement will depend upon the variations within the soil profile, the structural loading conditions, the embedment depth of the footings, the thickness of compacted fill, and the quality of the earthwork operations. 5. Passive resistance in the upper 12 inches of the soil profile should be neglected. Design Parameters - Uplift Loads Uplift resistance of spread footings can be developed from the effective weight of the footing and the overlying soils. As illustrated on the subsequent figure, the effective weight of the soil prism defined by diagonal planes extending up from the top of the perimeter of the foundation to the ground surface at an angle, q, of 20 degrees from the vertical can be included in uplift resistance. The maximum allowable uplift capacity should be taken as a sum of the effective weight of soil plus the dead weight of the foundation, divided by an appropriate factor of safety. A maximum total unit weight of 120 pcf should be used for the backfill. This unit weight should be reduced to 60 pcf for portions of the backfill or natural soils below the groundwater elevation. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 11 Foundation Construction Considerations As noted in Earthwork, the footing excavations should be observed by the Geotechnical Engineer. The base of all foundation excavations should be free of water and loose soil, prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing soil disturbance. Care should be taken to prevent wetting or drying of the bearing materials during construction. Excessively wet or dry material or any loose/disturbed material in the bottom of the footing excavations should be removed/reconditioned before foundation concrete is placed. Foundations should rest directly on aggregate piers which are outlined in the following section. GROUND IMPROVEMENT Mitigation of excessive settlement from static loading and/or seismic-induced ground motions (e.g., seismic-induced settlement) is generally accomplished through one of three methods: ■Removal of soils susceptible to excessive settlement and replacement with structural fill ■Densification of native soils through ground improvement ■Transfer foundation loads through weaker soils to competent soils using deep foundations Ground improvement options such as jet-grouting and deep soil-cement mixing densify the ground by mixing soil and cement to produce concrete-like columns. Deep foundations such as driven piles, augercast piles, and drilled shafts effectively mitigate excessive settlements. For cases where the design is controlled by horizontal loading, lateral resistance is accomplished through flexural bending which can result in relatively large pile diameters. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 12 The mitigation options of ground improvement and deep foundations mentioned above are generally expensive and may not be the most cost-effective solution. Assuming the structures can be designed to tolerate some lateral displacements while satisfying the seismic performance objective of life safety, ground improvement with aggregate piers is a viable, cost-effective solution. Aggregate piers are typically the preferred option when the following conditions exist: ■The site is relatively level and the risk of lateral spreading is low ■Unit of weaker soils and/or soils susceptible to liquefaction is relatively thin ■A bearing stratum is present at depths shallower than 60 feet, which is about the maximum depth aggregate piers can be installed using conventional methods Ground improvement techniques typically stiffen the ground enough such that spread footings connected with seismic ties are a feasible foundation option. However, ground improvement via aggregate piers does not mitigate lateral spreading. When a lateral spreading hazard exists, ground improvement to produce concrete-like columns may be needed. Deep foundations may also be an option, and a mat foundation could be adequate for some scenarios. For this site, we estimate that the thickness of liquefiable soil is about 10 to 12 feet and results in a post-liquefaction settlement ranging from 4 to 17 inches. While the final ground improvement design will be provided by the specialty contractor, we predict that piers will need to extend to approximately 15 to 20 feet below ground surface.The aggregate pier field should extend outside the building footprint by 5 feet or at least 10 percent of the building footprint, whichever is greater. It is recommended that a ground improvement contractor be consulted for design of the ground improvement system and the structural engineer consulted to provide the tolerable post- liquefaction displacements. Recommendations for foundations resting on aggregate piers are provided in the Shallow Foundations section. SPECIALTY FOUNDATIONS Small-Diameter Piles Small-diameter piles, or pin piles, are comprised of relatively small diameter steel pipe that is driven into the ground with a pneumatic or hydraulic jackhammer, or percussion driver, to a designated “refusal” criteria. Pipe lengths of 5 to 10 feet are commonly used. Successive pipe lengths are either compression coupled or welded together. Once the piles are installed, they are cut off to a pre-determined elevation, and the tops of the piles are then incorporated into new foundations or slabs as determined by the structural engineer. We recommend that the piles be driven to “refusal”. Definition of refusal criteria will depend on pipe diameter and construction installation methods. Pipes should penetrate several feet into the Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 13 bearing layer which is believed to be at a depth of 15 to 20 feet, therefore piles will likely reach 25 to 30 feet below ground surface. Determination of the depth to suitable bearing and the resultant pile capacities and depths will require field engineering decisions. We recommend that a representative from Terracon Consultants, Inc. observe the pile installation and refusal criteria achievement. Allowable axial capacity of pin piles is dependent on pipe diameter and schedule of steel and is outlined in the following table. Small Diameter Driven Pile Design Summary 1 Pile Diameter (inches) Schedule Steel Pipe Allowable Axial Capacity (kips) 2 80 4 3 40 12 4 40 20 1.Design capacities are dependent upon the method of installation, and quality control parameters. The values provided are estimates and should be verified when installation protocol have been finalized. We recommend at least one (and as many as five) load test be performed on an installed pile to confirm piles are providing the required axial support. We do not recommend that the pin piles be designed for lateral loading. A structural slab with a thickened edge utilizing passive earth pressure should be considered for resistance to lateral loading. Battering (i.e., inclining) the piles is another option to provide lateral resistance. Pin piles installed in this manner will not eliminate liquefaction settlements for the surrounding ground-supported elements including driveways, paved surfaces, awnings or other ancillary structures. However, provided that the recommendations of this report are followed, we anticipate the total and differential settlement of the building to be 3/4 inch and 1/2 inch for post-liquefaction loading conditions, respectively, assuming the piles are embedded in the dense bearing stratum. Because the ground surface may settle more than the building, we recommend that utilities be constructed with flexible connections to accommodate the differential settlement. SEISMIC CONSIDERATIONS The seismic design requirements for buildings and other structures are based on Seismic Design Category. Site Classification is required to determine the Seismic Design Category for a structure. The Site Classification is based on the upper 100 feet of the site profile defined by a weighted average value of either shear wave velocity, standard penetration resistance, or undrained shear strength in accordance with Section 20.4 of ASCE 7-10. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 14 Description Value 2015 International Building Code Site Classification 1 F1,2 Site Latitude 47.47861°N Site Longitude 122.21709°W SDS Spectral Acceleration for a Short Period 3 0.962g SD1 Spectral Acceleration for a 1-Second Period 3 0.540g 1.Seismic site classification in general accordance with the 2015 International Building Code, which refers to ASCE 7-10. Assuming the fundamental period of vibration for the building is less than 0.5 seconds, Site Class D may be used to determine values for the Site Parameters SS and S1. 2.The 2015 International Building Code (IBC) uses a site profile extending to a depth of 100 feet for seismic site classification. Borings at this site were extended to a maximum depth of 51 1/2 feet. The site properties below the boring depth to 100 feet were estimated based on our experience and knowledge of geologic conditions of the general area. Additional deeper borings or geophysical testing may be performed to confirm the conditions below the current boring depth. 3.These values for Site Class D were obtained using online seismic design maps and tools provided by the USGS (http://earthquake.usgs.gov/hazards/designmaps/). LIQUEFACTION Liquefaction is the phenomenon where saturated soils develop high pore water pressures during seismic shaking and lose their strength characteristics. This phenomenon generally occurs in areas of high seismicity, where groundwater is shallow and loose granular soils or relatively non- plastic fine-grained soils are present. Based on the site geology and subsurface groundwater conditions, the risk of liquefaction of the site soils is high during a design level earthquake and is most likely to trigger between 8 and 20 feet below the ground surface. Because the site is relatively level, the risk of lateral spreading is low and should be mitigated with seismic ties between spread footings or grade beams between pile caps. Liquefaction was evaluated using WSLiq software developed by Prof. Steven L. Kramer at the University of Washington (http://faculty.washington.edu/kramer/WSliq/WSliq.htm). We estimate between 4 and 16 inches of liquefaction-induced settlement of the ground surface based on our understanding of the regional geology and the alluvial deposits of the site. Vertical settlements deemed excessive by the structural engineer can be reduced using ground improvement or small diameter piles. However, the ground located outside the aggregate piers or piles will be subject to liquefaction-induced settlement. Therefore, we recommend any utilities connected to the proposed structures be designed with flexible connections to reduce damage during a seismic event. Foundation recommendations are provided in the Shallow Foundations section and discussion of aggregate piers is provided in the Ground Improvement section. Recommendations related to small diameter piles can be found in the Specialty Foundations section. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 15 FLOOR SLABS Floor slab design depends on the foundation approach. If ground improvement through aggregate piers is utilized under the entire footprint, a slab-on-grade is acceptable. In the case of small diameter piles, a structural slab supported on the piles will be necessary. Design parameters for floor slabs assume the requirements for Earthwork have been followed. Specific attention should be given to positive drainage away from the structure and. positive drainage of the aggregate base beneath the floor slab. Floor Slab Design Parameters Item Description Floor slab support 1 In the case of ground improvement, floor slab can rest directly on aggregate piers. If small diameter piles are used, a structural floor slab will be necessary. See Ground Improvement and Specialty Foundations sections for more detail. Aggregate base course/capillary break 2 6 inches of compacted free draining granular subbase material 1.Floor slabs should be structurally independent of building footings or walls to reduce the possibility of floor slab cracking caused by differential movements between the slab and foundation. 2.The floor slab design should include a capillary break, comprised of compacted, granular material, as described in subsection Fill Material Types. The use of a vapor retarder should be considered beneath concrete slabs on grade covered with wood, tile, carpet, or other moisture sensitive or impervious coverings, or when the slab will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer should refer to ACI 302 and/or ACI 360 for procedures and cautions regarding the use and placement of a vapor retarder. Saw-cut control joints should be placed in the slab to help control the location and extent of cracking. For additional recommendations refer to the ACI Design Manual. Joints or cracks should be sealed with a water-proof, non-extruding compressible compound specifically recommended for heavy duty concrete pavement and wet environments. Where floor slabs are tied to perimeter walls or turn-down slabs to meet structural or other construction objectives, our experience indicates differential movement between the walls and slabs will likely be observed in adjacent slab expansion joints or floor slab cracks beyond the length of the structural dowels. The Structural Engineer should account for potential differential settlement through use of sufficient control joints, appropriate reinforcing or other means. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 16 Floor Slab Construction Considerations Finished subgrade within and for at least 10 feet beyond the floor slab should be protected from traffic, rutting, or other disturbance and maintained in a relatively moist condition until floor slabs are constructed. If the subgrade should become damaged or desiccated prior to construction of floor slabs, the affected material should be removed and structural fill should be added to replace the resulting excavation. Final conditioning of the finished subgrade should be performed immediately prior to placement of the floor slab support course. The Geotechnical Engineer should approve the condition of the floor slab subgrades immediately prior to placement of the floor slab support course, reinforcing steel and concrete. Attention should be paid to high traffic areas that were rutted and disturbed earlier, and to areas where backfilled trenches are located. PAVEMENTS Pavement designs are provided for the traffic conditions and pavement life conditions as noted in Project Description and in the following sections of this report. A critical aspect of pavement performance is site preparation. Pavement designs, noted in this section, must be applied to the site, which has been prepared as recommended in the Earthwork section. Subgrade Preparation See the subsection Local Terracon General Pavement Design Recommendations for local practices and subgrade preparation options. The following are general subgrade preparation considerations standard to CFA, which apply for pavement subgrades prepared as recommended in the Earthwork section. On most project sites, the site grading is accomplished relatively early in the construction phase. Fills are placed and compacted in a uniform manner. However, as construction proceeds, excavations are made into these areas, rainfall and surface water saturates some areas, heavy traffic from concrete trucks and other delivery vehicles disturbs the subgrade and many surface irregularities are filled in with loose soils to improve traffic conditions temporarily. As a result, the pavement subgrades, initially prepared early in the project, should be carefully evaluated as the time for pavement construction approaches. We recommend the moisture content and density of the top 12 inches of the subgrade be evaluated and the pavement subgrades be proofrolled within two days or after a rainfall prior to commencement of actual paving operations. Areas not in compliance with the required ranges of moisture or density should be moisture conditioned and recompacted. Particular attention should be paid to high traffic areas that were rutted and disturbed earlier and to areas where backfilled trenches are located. Areas where unsuitable conditions are located should be repaired by Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 17 removing and replacing the materials with properly compacted fills. If a significant precipitation event occurs after the evaluation or if the surface becomes disturbed, the subgrade should be reviewed by qualified personnel immediately prior to paving. The subgrade should be in its finished form at the time of the final review. Design Considerations Actual traffic patterns and anticipated loading conditions were not available at the time that this report was prepared. However, we anticipate that traffic loads will be produced primarily by automobile traffic and occasional delivery and trash removal trucks. The thickness of pavements subjected to heavy truck traffic should be determined using expected traffic volumes, vehicle types, and vehicle loads and should be in accordance with local, city or county ordinances. Pavement thickness can be determined using AASHTO, Asphalt Institute and/or other methods if specific wheel loads, axle configurations, frequencies, and desired pavement life are provided. Terracon can provide thickness recommendations for pavements subjected to loads other than personal vehicle and occasional delivery and trash removal truck traffic if this information is provided. Standard CFA Estimates of Minimum Pavement Thickness The following section provides the standard CFA recommended pavement sections according to provided information. As a minimum, we recommend the following typical pavement section be considered for car only areas. Material Thickness (inches)Preparation Subgrade 24 inches of structural fill placed and compacted in two lifts of 18 and 6 inches.1 95% of Modified Proctor -2% to +2% optimum moisture content Aggregate Base 2 6 Minimum CFA recommended base course thickness Asphalt Surface Course 4 Minimum CFA recommended binder course (2.5 inches) and surface course (1.5 inches) Total Pavement Section 10 1. Increased thickness from CFA standard. 2. A material similar to WSDOT: 9-03.9(3) Base Course, or approved alternate. We can review proposed materials during construction. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 18 As a minimum, we suggest the following typical pavement section be considered for combined car and delivery truck traffic. Material Thickness (inches)Preparation Subgrade 24 inches of structural fill placed and compacted in two lifts of 18 and 6 inches.1 95% of Modified Proctor -2% to +2% optimum moisture content Aggregate Base 2 7 Increased recommended base course thickness Asphalt Surface Course 4 Minimum CFA recommended binder course (2.5 inches) and surface course (1.5 inches) Total Pavement Section 11 1. Increased thickness from CFA standard. 2. A material similar to WSDOT: 9-03.9(3) Base Course, or approved alternate. We can review proposed materials during construction. The graded aggregate base should be compacted to a minimum of 95 percent of the material’s modified Proctor (ASTM D-1557, Method C) maximum dry density. The listed pavement component thicknesses should be used as a guide for pavement systems at the site for the traffic classifications stated herein. These recommendations assume a 20-year pavement design life. If pavement frequencies or loads will be different than that specified Terracon should be contacted and allowed to review these pavement sections. We recommend a Portland cement concrete (PCC) pavement be utilized in entrance and exit sections, dumpster pads, loading dock areas, or other areas where extensive wheel maneuvering are expected. The dumpster pad should be large enough to support the wheels of the truck which will bear the load of the dumpster. We recommend a minimum of 6 inches of PCC underlain by 4 inches of granular aggregate base. Although not required for structural support, the base course layer is utilized to help reduce potentials for slab curl, shrinkage cracking, and subgrade “pumping” through joints. Proper joint spacing will also be required to prevent excessive slab curling and shrinkage cracking. All joints should be sealed to prevent entry of foreign material and dowelled where necessary for load transfer. Portland cement concrete should be designed with proper air-entrainment and have a minimum compressive strength of 4,000 psi after 28 days of laboratory curing. Adequate reinforcement and number of longitudinal and transverse control joints should be placed in the rigid pavement in accordance with ACI requirements. The joints should be sealed as soon as possible (in accordance with sealant manufacturer’s instructions) to minimize infiltration of water into the soil. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 19 Local Terracon General Pavement Design Recommendations Subgrade The Standard CFA minimums for pavement subgrade and design standards will be sufficient in the Puget Sound region. As recommended in the Earthwork section, over-excavation in the pavement areas should extend to 2 feet below the bottom of the pavement section, including the aggregate base. A geotextile, such as Mirafi 500x should be installed at the base of the excavation to provide separation between the soft subgrade and the structural fill. Above the geotextile, structural fill should be placed in two lifts of 18 inches and 6 inches. Each lift can be compacted with a vibratory roller under the observation of a geotechnical engineer. If movement of the subgrade is observed during dynamic compaction, static compaction methods should be employed and we may recommend that the 24 inches of structural fill be placed in a single lift. Pavement Design We recommend the standard CFA pavement sections as described above for this site. A formal pavement design has not been completed for this project. The above recommended pavement sections are typical minimum values and thicker pavement sections could be used to reduce maintenance and extend the expected service life of the pavements. Periodic maintenance will also extend the service life of the pavements and should include patching and repair of deteriorated areas, crack sealing, and surface sealing. We recommend that a formal pavement design be completed if unusually high vehicle loads or frequencies are anticipated. Construction Considerations Construction scheduling often involves grading and paving by separate contractors and can involve a time lapse between the end of grading operations and the commencement of paving. Disturbance, desiccation or wetting of the subgrade soils between grading and paving can result in deterioration of the previously completed subgrade. A non-uniform subgrade can result in poor pavement performance and local failures relatively soon after pavements are constructed. We recommend the moisture content and density of the subgrade be evaluated within two days prior to commencing paving operations. A proof roll using heavy equipment similar to that required for pavement construction is also recommended to verify subgrade stability for pavement construction. Scarification and recompaction may also be required. Construction traffic on the pavements was not considered in developing the recommended minimum pavement thicknesses. Construction traffic can cause significant damage to pavements, especially to partially-completed pavement sections (e.g., base course lifts). If the pavements will be subject to traffic by construction equipment/vehicles, the pavement thicknesses should be revised to consider the effects of the additional loading. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 20 Areas not in compliance with the required ranges of moisture or density should be moisture conditioned and recompacted. If significant precipitation occurs after the evaluation or if the surface becomes disturbed, the subgrade condition should be reviewed by Terracon personnel immediately prior to paving. Pavement Drainage Pavements should be sloped to provide rapid drainage of surface water. Water allowed to pond on or adjacent to the pavements could saturate the subgrade and contribute to premature pavement deterioration. In addition, the pavement subgrade should be graded to provide positive drainage within the granular base section. We recommend drainage be included at the bottom of the aggregate layer at the storm structures to aid in removing water that may enter this layer. Drainage could consist of small diameter weep holes excavated around the perimeter of the storm structures. The weep holes should be excavated at the elevation of the aggregate and soil interface. The excavation should be covered with No. 57 stone which is encompassed in Mirafi 140 NL or approve equivalent which will aid in reducing fines from entering the storm system. Pavement Maintenance The pavement sections provided in this report represent minimum recommended thicknesses and, as such, periodic maintenance should be anticipated. Therefore, preventive maintenance should be planned and provided for through an on-going pavement management program. Preventive maintenance activities are intended to slow the rate of pavement deterioration, and to preserve the pavement investment. Preventive maintenance consists of both localized maintenance (e.g., crack and joint sealing and patching) and global maintenance (e.g., surface sealing). Preventive maintenance is usually the first priority when implementing a planned pavement maintenance program and provides the highest return on investment for pavements. Prior to implementing any maintenance, additional engineering observation is recommended to determine the type and extent of preventive maintenance. Even with periodic maintenance, some movements and related cracking may still occur and repairs may be required. GENERAL COMMENTS Terracon should be retained to review the final design plans and specifications so comments can be made regarding interpretation and implementation of our geotechnical recommendations in the design and specifications. Terracon also should be retained to provide observation and testing services during grading, excavation, foundation construction and other earth-related construction phases of the project. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable 21 The analysis and recommendations presented in this report are based upon the data obtained from the borings performed at the indicated locations and from other information discussed in this report. This report does not reflect variations that may occur between borings, across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided. The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing. ATTACH MENTS ATTACHMENTS Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES Field Exploration As requested, our field exploration work included the drilling and sampling of exploratory soil borings consistent with the following schedule. Number of Borings Boring Depth (ft)1 Planned Location 2 4 16 ½ - 51 ½Building Pad 3 6 ½Pavement Areas 1 6 ½Dumpster Pad 1. Below existing ground surface 2. See Exploration Plan Boring Layout and Elevations: A Terracon representative used field measurements from existing site features to mark the boring locations prior to drilling operations. Approximate elevations were obtained from Google Earth Pro and are reported to the nearest foot. Subsurface Exploration Procedures: We advanced soil borings with a truck-mounted drill rig using continuous hollow-stem flight augers, a combination of hollow-stem auger and mud rotary was used for the deepest boring, B-4. Samples were obtained at a 2 ½ foot interval in the upper 16 ½ feet of each boring and at intervals of 5 feet thereafter. Soil sampling was performed using split-barrel sampling procedures. In the split-barrel sampling procedure, a standard 2-inch outer diameter split-barrel sampling spoon is driven into the ground by a 140-pound automatic hammer falling a distance of 30 inches. The number of blows required to advance the sampling spoon the last 12 inches of a normal 18-inch penetration is recorded as the Standard Penetration Test (SPT) resistance value. The SPT resistance values, also referred to as N-values, are indicated on the boring logs at the test depths. A 3-inch O.D. split-barrel sampling spoon with 2.5-inch I.D. ring lined sampler was used for sampling in below 25 feet on B-4. Ring-lined, split-barrel sampling procedures are similar to standard split spoon sampling procedure; however blow counts must be adjusted to account for the larger diameter sampler. The samples were sealed and taken to our soil laboratory for testing, and classified by a geotechnical engineer. In addition, we observed and recorded groundwater levels during drilling. Our exploration team prepared field boring logs as part of standard drilling operations including sampling depths, penetration distances, and other relevant sampling information. Field logs include visual classifications of materials encountered during drilling, and our interpretation of subsurface conditions between samples. Final boring logs, prepared from field logs, represent the geotechnical engineer's interpretation, and include modifications based on observations and laboratory tests. Geotechnical Engineering Report Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Responsive ■Resourceful ■Reliable Property Disturbance: We backfilled borings with bentonite chips after completion. Pavements were patched with quick-dry concrete. Our services did not include repair of the site beyond backfilling our boreholes, and patching existing pavements. Because backfill material often settles below the surface after a period, we recommend boreholes be checked periodically and backfilled, if necessary. We can provide this service, or grout the boreholes for additional fees, at your request. Laboratory Testing The project engineer reviewed field data and assigned various laboratory tests to better understand the engineering properties of various soil strata. Testing included visual classification, moisture content, and percent finer than no. 200 sieve as appropriate. In addition to our standard testing, Atterberg Limits tests were performed on two selected samples. Procedural standards noted below are for reference to methodology in general. In some cases, local practices and professional judgement require method variations. Standards noted below include reference to other related standards. Such references are not necessarily applicable to describe the specific test performed. ■ASTM D2488 Description and Identification of Soils (Visual-Manual Procedure) ■ASTM D2216 Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass ■ASTM D4318 Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils ■ASTM D1140 Standard Test Methods for Amount of Material in Soils Finer than No. 200 Sieve Our laboratory testing program often includes examination of soil samples by an engineer. Based on the material’s texture and plasticity, we describe and classify soil samples in accordance with the Unified Soil Classification System (USCS). SITE LOCA TION AND EXPLORATION PLANS SITE LOCATION AND EXPLORATION PLANS EXPLORATION PLAN Chick-fil-A #04249- Renton ■ Renton, King County WA June 21, 2018 ■ Terracon Project No. 81185084 DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES AERIAL PHOTOGRAPHY PROVIDED BY MICROSOFT BING MAPS EXPLORATION PLAN Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, WA June 21, 2018 ■ Terracon Project No. 81185084 DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES THIS BASEMAP PDF WAS PROVIDED BY CHICK-FIL-A AND MODIFIED BY TERRACON EXPLORATION PLAN Chick-fil-A #04249- Renton ■ Renton, WA June 21, 2018 ■ Terracon Project No. 81185084 DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES AERIAL PHOTOGRAPHY PROVIDED BY MICROSOFT BING MAPS EXPLORATION RESULTS EXPLORATION RESULTS 42 28 27 27 17 14 11.5 1-1-1 N=2 0-0-0 N=0 0-0-0 N=0 1-1-4 N=5 1-2-4 N=6 4-17-20 N=37 S-1 S-2 S-3 S-4A S-4B S-5 S-6 0.2 0.9 1.1 11.0 14.0 16.5 ASPHALT FILL - SANDY GRAVEL (GM), brown, moist, FILL ASPHALT SILT (ML), with interbedded fine sands, light reddish brown with iron stain, wet, very soft, alluvial becomes gray, wood debri POORLY GRADED SAND (SP), with trace silt, brown to gray, wet, loose, alluvial SANDY GRAVEL (GW), light brown, wet, dense, alluvial Boring Terminated at 16.5 FeetGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 28 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 10 15 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4784° Longitude: -122.2167° Page 1 of 1 Advancement Method: Hollow Stem Auger Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite Surface capped with concrete 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-31-2018 BORING LOG NO. B-1 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-31-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: While drilling WATER LEVEL OBSERVATIONS 26.5 26 26 23 16.5 10 6.5 1-2-2 N=4 1-0-1 N=1 0-0-0 N=0 0-1-3 N=4 2-5-8 N=13 2-4-7 N=11 2-9-7 N=16 S-1 S-2 S-3 S-4A S-4B S-5 S-6 S-7 0.3 0.8 1.0 4.0 10.5 17.0 20.5 ASPHALT SILTY GRAVEL WITH SAND (GM), light brown, moist, FILL ASPHALT SAND (SP), with trace silt, brown and reddish brown, wet, loose, interbedded layers of silt with trace sand alluvial SILT (ML), light brown to gray, wet, very soft, iron staining, alluvial POORLY GRADED SAND (SP), with trace silt, light brown, very loose to loose, alluvial becomes medium dense, light reddish brown interbedded fine sand with silt brown grading to gray wood debri SANDY GRAVEL (GP), brown, wet, medium dense, alluvial Boring Terminated at 20.5 FeetGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 27 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 10 15 20 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4783° Longitude: -122.2169° Page 1 of 1 Advancement Method: Hollow Stem Auger Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite Surface capped with concrete 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-31-2018 BORING LOG NO. B-2 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-31-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: WATER LEVEL OBSERVATIONS 21 16 11 1.5 1-2-3 N=5 1-0-1 N=1 1-0-0 N=0 0-0-0 N=0 0-1-2 N=3 1-2-6 N=8 10-11-16 N=27 14-21-22 N=43 S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 7.0 12.0 17.0 26.5 SAND WITH SILT (SP-SM), fine grained, brown and reddish brown, moist, loose increased silt content, becomes very soft and wet SILT (ML), brown to gray, wet, very soft, localized organics SAND WITH SILT (SP-SM), gray, wet, very loose to loose, with interbedded layers of very silty fine sand SANDY GRAVEL (GP), trace silt, light brown, wet, medium dense to dense Boring Terminated at 26.5 FeetGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 28 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 10 15 20 25 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4785° Longitude: -122.2168° Page 1 of 1 Advancement Method: Hollow Stem Auger Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-30-2018 BORING LOG NO. B-3 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-30-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: While drilling WATER LEVEL OBSERVATIONS 82 19 9 46 44 33-28-5 34-28-6 16 13 8.5 1-0-2 N=2 0-0-0 N=0 0-0-0 N=0 0-0-0 N=0 1-1-2 N=3 1-2-4 N=6 7-10-14 N=24 5-17-41 N=58 S-1 S-2 S-3 S-4 S-5 S-6 S-7 S-8 12.0 15.0 19.5 SILT WITH SAND (ML), brown with iron stain, moist to wet, very soft interbedded silty sand weight of hammer advanced sampler 1.5' wet, color becomes gray weight of hammer advanced sampler 1.5' SILTY SAND (SM), light brown to reddish brown, wet, very loose, with interbedded silt SAND WITH SILT (SP-SM), light brown to reddish brown, wet, loose, with iron stain SANDY GRAVEL (GP), reddish brown, wet, medium dense becomes dense @ 25 ft. switched to 3" outer diameter sampler for the remainder of the boringGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 28 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 10 15 20 25 30 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4784° Longitude: -122.217° Page 1 of 2 Advancement Method: Hollow Stem Auger and Mud Rotary Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-30-2018 BORING LOG NO. B-4 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-30-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: WATER LEVEL OBSERVATIONS -23.5 14-20-20 N=40 9-16-17 N=33 17-50/5" N=50/5" 21-28-33 N=61 10-32-27 N=59 S-9 S-10 S-11A S-11B S-12 S-13 51.5 SANDY GRAVEL (GP), reddish brown, wet, medium dense (continued) decreased sand content Approximate 6" sand seam @ 40' becomes very dense Boring Terminated at 51.5 Feet @ 25 ft. switched to 3" outer diameter sampler for the remainder of the boringGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 28 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)35 40 45 50 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4784° Longitude: -122.217° Page 2 of 2 Advancement Method: Hollow Stem Auger and Mud Rotary Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-30-2018 BORING LOG NO. B-4 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-30-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: WATER LEVEL OBSERVATIONS 42 27.5 27.5 26 25 23 21.5 2-1-2 N=3 1-2-2 N=4 S-1 S-2 0.3 0.6 2.0 3.0 5.0 6.5 ASPHALT AGGREGATE BASE COURSE WELL GRADED GRAVEL WITH SILT AND SAND (GW-GM), brown, (FILL) SILT WITH SAND (ML), brown, (FILL) SILT (ML), brown and reddish brown, wet, soft, (alluvial) SAND WITH SILT (SP-SM), reddish brown, moist to wet, very loose, interbedded silt with fine sand (alluvial) Boring Terminated at 6.5 FeetGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 28 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4788° Longitude: -122.2175° Page 1 of 1 Advancement Method: Hollow Stem Auger Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite Surface capped with concrete 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-31-2018 BORING LOG NO. B-5 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-31-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: WATER LEVEL OBSERVATIONS 35 27.5 27.5 26 21.5 2-1-1 N=2 0-0-1 N=1 S-1 S-2 0.4 0.5 2.0 6.5 ASPHALT AGGREGATE BASE COURSE POORLY GRADED GRAVEL WITH SILT AND SAND, brown, moist, (FILL) SILT (ML), gray, wet, very soft to soft, (alluvial) with thin interbedded fine sand with silt and fine sandy silt Boring Terminated at 6.5 FeetGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 28 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4787° Longitude: -122.2169° Page 1 of 1 Advancement Method: Hollow Stem Auger Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite Surface capped with concrete 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-31-2018 BORING LOG NO. B-6 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-31-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: WATER LEVEL OBSERVATIONS 34 26.5 21.5 1-1-1 N=2 1-0-1 N=1 S-1 S-2 1.7 6.5 SILTY GRAVEL WITH SAND (GM), light brown, moist, (FILL) SILT (ML), with thin interbedded fine sandy silt and silty fine sand, reddish brown, wet, very soft to soft Boring Terminated at 6.5 FeetGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 28 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4786° Longitude: -122.2171° Page 1 of 1 Advancement Method: Hollow Stem Auger Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 05-31-2018 BORING LOG NO. B-7 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 05-31-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: WATER LEVEL OBSERVATIONS 36 26 25.5 24 19.5 1-1-2 N=3 2-1-1 N=2 S-1 S-2 0.2 0.3 2.0 6.5 ASPHALT AGGREGATE BASE COURSE SILTY GRAVEL WITH SAND (GM), light brown to gray brown, damp to moist, (FILL) SILT WITH SAND (ML), light brown to reddish brown, moist to wet, very soft to soft, with iron staining, (alluvial) Boring Terminated at 6.5 FeetGRAPHIC LOGHammer Type: Automatic, ETR = 87%Stratification lines are approximate. In-situ, the transition may be gradual.THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/21/18PERCENT FINESWATERCONTENT (%)LL-PL-PI ATTERBERG LIMITS ELEVATION (Ft.) Surface Elev.: 26 (Ft.)WATER LEVELOBSERVATIONSDEPTH (Ft.)5 SAMPLE TYPEFIELD TESTRESULTSSAMPLE NUMBERDEPTH LOCATION See Exploration Plan Latitude: 47.4782° Longitude: -122.2172° Page 1 of 1 Advancement Method: Hollow Stem Auger Abandonment Method: Boring backfilled with Auger Cuttings and/or Bentonite Surface capped with concrete 21905 64th Ave W, Ste 100 Mountlake Terrace, WA Notes: Project No.: 81185084 Drill Rig: CME-85 Boring Started: 06-01-2018 BORING LOG NO. B-8 Chick-fil-A, Inc.CLIENT: Irvine, CA Driller: Gregory Boring Completed: 06-01-2018 PROJECT: Chick-fil-A #04249 Renton See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations. Rainer Ave & 3rd Renton, WA SITE: WATER LEVEL OBSERVATIONS 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 1 140 U.S. SIEVE NUMBERS 44 1006321014501620 100 90 80 70 60 50 40 30 20 10 0 3 60 HYDROMETERU.S. SIEVE OPENING IN INCHES ASTM D422 / ASTM C136 PERCENT FINER BY WEIGHTPERCENT COARSER BY WEIGHTGRAIN SIZE DISTRIBUTION GRAIN SIZE IN MILLIMETERS 3/4 1/2 3/8 30 406 2001.5 8 finemediumCOBBLESGRAVELSAND SILT OR CLAYcoarse % COBBLESDEPTH D10 GRAIN SIZE SOIL DESCRIPTION USCS REMARKS COEFFICIENTS Silt with Sand (ML) Silty Sand (SM) Sand with Silt (SP-SM) 7.5 - 9 12.5 - 14 15 - 16.5 81.6 18.9 9.0 B-4 B-4 B-4 % Finer fine coarse % SAND% GRAVEL % SILT Sieve D30 D60 BORING ID #200 81.61 #200 18.86 8.99#200 Sieve % Finer Sieve % Finer % FINES % CLAY CC CU PROJECT NUMBER: 81185084 SITE: Rainer Ave & 3rd Renton, WA PROJECT: Chick-fil-A #04249 Renton CLIENT: Chick-fil-A, Inc. Irvine, CA 21905 64th Ave W, Ste 100 Mountlake Terrace, WA LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: AASHTO DESC-1 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/19/18 0 10 20 30 40 50 60 0 20 40 60 80 100CH or OHCL or OLML or OL MH or OH"U" Line"A" Line ATTERBERG LIMITS RESULTS ASTM D4318 P L A S T I C I T Y I N D E X LIQUID LIMIT PROJECT NUMBER: 81185084 SITE: Rainer Ave & 3rd Renton, WA PROJECT: Chick-fil-A #04249 Renton CLIENT: Chick-fil-A, Inc. Irvine, CA 21905 64th Ave W, Ste 100 Mountlake Terrace, WA LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. ATTERBERG LIMITS 81185084 CHICK-FIL-A #0424.GPJ TERRACON_DATATEMPLATE.GDT 6/19/185 - 6.5 10 - 11.5 33 34 28 28 5 6 Silt with Sand (ML) Silt with Sand (ML) DescriptionUSCSFinesPIPLLLBoring ID Depth B-4 B-4 CL-ML SUPPORTING INFORMA TION SUPPORTING INFORMATION GENERAL NOTES & UNIFIED SOIL CLASSIFICATION SYSTEM Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 UNIFIED SOIL CLASSIFICATION SYSTEMDRILLING & SAMPLING SYMBOLS: SS:Split Spoon – 1-3/8" I.D., 2" O.D., unless otherwise noted HS: Hollow Stem Auger ST:Thin-Walled Tube - 3" O.D., unless otherwise noted PA: Power Auger RS:Ring Sampler - 2.42" I.D., 3" O.D., unless otherwise noted HA: Hand Auger DB:Diamond Bit Coring - 4", N, B RB: Rock Bit BS:Bulk Sample or Auger Sample WB: Wash Boring or Mud Rotary The number of blows required to advance a standard 2-inch O.D. split-spoon sampler (SS) the last 12 inches of the total 18-inch penetration with a 140-pound hammer falling 30 inches is considered the “Standard Penetration” or “N-value”. WATER LEVEL MEASUREMENT SYMBOLS: WL:Water Level WS:While Sampling N/E: Not Encountered WCI:Wet Cave in WD:While Drilling DCI:Dry Cave in BCR:Before Casing Removal AB:After Boring ACR:After Casing Removal Water levels indicated on the boring logs are the levels measured in the borings at the times indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only short-term observations. DESCRIPTIVE SOIL CLASSIFICATION:Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency. CONSISTENCY OF FINE-GRAINED SOILS RELATIVE DENSITY OF COARSE-GRAINED SOILS Unconfined Compressive Strength, Qu, psf Standard Penetration or N-value (SS) Blows/Ft. Consistency Standard Penetration or N-value (SS) Blows/Ft. Ring Sampler (RS) Blows/Ft.Relative Density < 500 0-1 Very Soft 0 – 3 0-6 Very Loose 500 – 1,000 2-3 Soft 4 – 9 7-18 Loose 1,001 – 2,000 4-6 Medium Stiff 10 – 29 19-58 Medium Dense 2,001 – 4,000 7-12 Stiff 30 – 49 59-98 Dense 4,001 – 8,000 13-26 Very Stiff 50+99+Very Dense 8,000+26+Hard RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY Descriptive Term(s) of other Constituents Percent of Dry Weight Major Component of Sample Particle Size Trace < 15 Boulders Over 12 in. (300mm) With 15 – 30 Cobbles 12 in. to 3 in. (300mm to 75 mm) Modifier > 30 Gravel 3 in. to #4 sieve (75mm to 4.75 mm) Sand Silt or Clay #4 to #200 sieve (4.75mm to 0.075mm) Passing #200 Sieve (0.075mm) RELATIVE PROPORTIONS OF FINES PLASTICITY DESCRIPTION Descriptive Term(s) of other Constituents Percent of Dry Weight Term Plasticity Index Trace < 5 Non-plastic 0 With 5 – 12 Low 1-10 Modifier > 12 Medium 11-30 High 30+ GENERAL NOTES & UNIFIED SOIL CLASSIFICATION SYSTEM Proposed Chick-fil-A Restaurant #04249 ■ Renton, King County, Washington June 21, 2018 ■ Terracon Project No. 81185084 Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A Soil Classification Group Symbol Group Name B Coarse-Grained Soils: More than 50% retained on No. 200 sieve Gravels: More than 50% of coarse fraction retained on No. 4 sieve Clean Gravels: Less than 5% fines C Cu ‡ 4 and 1 £ Cc £ 3 E GW Well-graded gravel F Cu < 4 and/or 1 > Cc > 3 E GP Poorly graded gravel F Gravels with Fines: More than 12% fines C Fines classify as ML or MH GM Silty gravel F, G, H Fines classify as CL or CH GC Clayey gravel F, G, H Sands: 50% or more of coarse fraction passes No. 4 sieve Clean Sands: Less than 5% fines D Cu ‡ 6 and 1 £ Cc £ 3 E SW Well-graded sand I Cu < 6 and/or 1 > Cc > 3 E SP Poorly graded sand I Sands with Fines: More than 12% fines D Fines classify as ML or MH SM Silty sand G, H, I Fines classify as CL or CH SC Clayey sand G, H, I Fine-Grained Soils: 50% or more passes the No. 200 sieve Silts and Clays: Liquid limit less than 50 Inorganic:PI > 7 and plots on or above “A” line J CL Lean clay K, L, M PI < 4 or plots below “A” line J ML Silt K, L, M Organic:Liquid limit - oven dried < 0.75 OL Organic clay K, L, M, N Liquid limit - not dried Organic silt K, L, M, O Silts and Clays: Liquid limit 50 or more Inorganic:PI plots on or above “A” line CH Fat clay K, L, M PI plots below “A” line MH Elastic Silt K, L, M Organic:Liquid limit - oven dried < 0.75 OH Organic clay K, L, M, P Liquid limit - not dried Organic silt K, L, M, Q Highly organic soils:Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-inch (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles or boulders, or both” to group name. C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay E Cu = D60/D10 Cc = 6010 2 30 DxD )(D F If soil contains ‡ 15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. H If fines are organic, add “with organic fines” to group name. I If soil contains ‡ 15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant. L If soil contains ‡ 30% plus No. 200 predominantly sand, add “sandy” to group name. MIf soil contains ‡ 30% plus No. 200, predominantly gravel, add “gravelly” to group name. N PI ‡ 4 and plots on or above “A” line. O PI < 4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line.