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REVIEWED BLD2022-1541+Geotechnical_Report+11.9.2022_12.23.33_PM+3211665BLD2022-1541 RECEIVED Nov 15 2022 ......... - oEP�mmENT REVIEWED BY CITY OF EDMONDS BUILDING DEPARTMENT: GEOTECHNICAL ENGINEERING INVESTIGATION PROPOSED GLACIER OFFICES AND WAREHOUSE 7509 212TH STREET SW EDMONDS, WA 98026 PROJECT No. 092-22001 FEBRUARY 04, 2022 Prepared for: GLACIER ENVIRONMENTAL SERVICES, INC ATTN: LAUREN GOLEMBIEWSKI, PRESIDENT 7509 212TH STREET SW EDMONDS, WA 98026 Prepared by: KRAZAN & ASSOCIATES, INC. GEOTECHNICAL ENGINEERING DIVISION 4303 —198TH STREET SW LYNNWOOD, WASHINGTON 98036 (425) 485-5519 -Krazan & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION February 04, 2022 Glacier Environmental Services, Inc. P.O. Box 1097 Mukilteo, WA 98275 Attn: Ms. Lauren Golembiewski, President Email: Imiles@glacierenviro.com Tel: 425-268-9775 RE: GEOTECHNICAL ENGINEERING INVESTIGATION Proposed Glacier Offices and Warehouse 7509 212'' Street SW Edmonds, WA 98026 Dear Ms. Golembiewski, KA Project No. 092-22001 In accordance with your request, we have completed a Geotechnical Engineering Investigation for the referenced site. The results of our investigation are presented in the attached report. If you have any questions, or if we can be of further assistance, please do not hesitate to contact our office. Respectfully submitted, KRAZAN & ASSOCIATES, INC. Michael D. Rundquist, P.E. Senior Project Manager MDR IN, Offices Serving The Western United States 4303 —198t' Street SW • Lynnwood, Washington 98036 • (425) 485-5519 • Fax: (425) 485-6837 -I'('a7_ a1 & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION TABLE OF CONTENTS INTRODUCTION....................................................................................................................................................... 1 PROJECTDESCRIPTION........................................................................................................................................ 1 PURPOSEAND SCOPE............................................................................................................................................. 2 SITECONDITIONS................................................................................................................................................... 3 GEOLOGICSETTING.............................................................................................................................................. 3 FIELDINVESTIGATION......................................................................................................................................... 3 SOIL PROFILE AND SUBSURFACE CONDITIONS............................................................................................. 4 GROUNDWATER...................................................................................................................................................... 6 GEOLOGICHAZARDS............................................................................................................................................ 6 ErosionConcern/Hazard...................................................................................................................................... SeismicHazard................................................................................................................................................... CONCLUSIONS AND RECOMMENDATIONS...................................................................................................... 8 General........................................................................................................................................ SitePreparation............................................................................................................................ TemporaryExcavations................................................................................................................ StructuralFill............................................................................................................................... ShallowFoundations.................................................................................................................... Floor Slabs and Exterior Flatwork................................................................................................ Lateral Earth Pressures and Retaining Walls................................................................................. Stormwater Management.............................................................................................................. OrganicContent........................................................................................................................... CationExchange Capacity............................................................................................................ Erosion and Sediment Control...................................................................................................... Groundwater Influence on Structures/ Construction...................................................................... Drainage and Landscaping........................................................................................................... UtilityTrench Backfill................................................................................................................. Testingand Inspection.................................................................................................................. ............................. 8 ............................. 9 ........................... 10 ........................... 11 ........................... 11 ........................... 13 ........................... 13 ........................... 14 ........................... 16 ........................... 16 ........................... 17 ........................... 18 ........................... 18 ........................... 18 ........................... 19 LIMITATIONS......................................................................................................................................................... 20 VICINITYMAP.............................................................................................................................. Figure 1 SITEPLAN...................................................................................................................................... Figure 2 FIELD INVESTIGATION AND LABORATORY TESTING ................................................ Appendix A EARTHWORK SPECIFICATIONS........................................................................................ Appendix B PAVEMENT SPECIFICATIONS............................................................................................ Appendix C Offices Serving The Western United States 4303 — 19811 Street SW 9 Lynnwood, Washington 98036 9 (425) 485-5519 9 Fax: (425) 485-6837 �Irazan & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION February 04, 2022 KA Project No. 092-22001 GEOTECHNICAL ENGINEERING INVESTIGATION PROPOSED GLACIER OFFICES AND WAREHOUSE 7509 212TH STREET SW EDMONDS, WASHINGTON 98026 INTRODUCTION This report presents the results of our geotechnical engineering investigation for the commercial project located at 7509 212th Street SW in Edmonds, Washington, as shown on the Vicinity Map in Figure 1. Discussions regarding site conditions are presented in this report, together with conclusions and recommendations pertaining to site preparation, excavations, structural fill, foundations, drainage and landscaping, and erosion control. We have been requested to conduct a geotechnical investigation regarding foundation support and stormwater infiltration testing to aid in project design. A site plan showing the approximate exploratory test pit and infiltration test locations is presented in Figure 2 following the text of this report. Appendix A includes a description of the field investigation and the soil logs. Appendix B contains a guide to aid in the development of earthwork specifications. Pavement design guidelines are presented in Appendix C. The recommendations in the main text of the report have precedence over the more general specifications in the appendices. PROJECT DESCRIPTION The site is roughly rectangular in shape and is located on the north side of 212th Street SW, approximately 250 feet east of the intersection with 76th Avenue W. The property covers an area of approximately 0.87 acres. A commercial property borders the site to the west. Residential properties border the site to the north and east. 212th Street SW borders the site to the south. A residence, accessory dwelling units and small storage barn currently occupy the property. Minimal grading is anticipated for the demolition of existing structures and the construction of the new facilities. The proposed development will include design and construction of a new two-story office building and a pre-fab metal warehouse, along with associated utilities, pavement, and landscape areas. A bio-retention swale along the eastern edge of the property is under consideration for this project. Offices Serving The Western United States 4303 — 198"' Street SW 9 Lynnwood, Washington 98036 9 (425) 485-5519 9 Fax: (425) 485-6837 Krazan & Associates, Inc. PURPOSE AND SCOPE KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 2 This investigation was conducted to evaluate the subsurface soil and groundwater conditions at the site, to develop geotechnical engineering recommendations for use in design of specific construction elements, and to provide criteria for earthwork construction. Our services were performed in general accordance with our proposal for this project, dated January 11, 2022 (Proposal Number G22018WAL) and included the following: • Explore the subsurface soil conditions with test pit excavations in the project area. Soil samples were collected for laboratory testing. • Prepare a site plan showing the test pit locations; • Prepare test pit logs including soil stratification and classification, and groundwater levels where applicable; • Provide recommendations for foundation design including foundation type, allowable foundation bearing pressure, anticipated settlements (both total and differential), coefficient of horizontal friction, and frost penetration depth; • Provide recommendations for retaining wall design including lateral earth pressures (active and passive); • Provide recommendations for seismic design considerations, including site coefficient and ground acceleration based on the 2018 International Building Code (IBC); • Provide soil parameters for the design of slab -on -grade floors including recommendations for placement of capillary break material and vapor barrier below the slabs; • Discuss construction and excavation considerations, topsoil/unsuitable soil stripping depth, identification of potentially problematic soils or groundwater conditions, and depth of over - excavation if required; • Provide opinions on the feasibility of stormwater infiltration on this site, and design infiltration rates where feasible; • Provide recommendations for structural fill materials, placement, and compaction; • Provide recommendations for temporary excavations; • Provide recommendations for site drainage and erosion control; and • Provide recommendations for standard and heavy-duty pavement design. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. SITE CONDITIONS KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 3 The project site is located in a mixed residential and commercial neighborhood about three blocks west of Highway 99. The site slopes gently down to the northwest and to the south from a high point in the central portion of the property. The site is vegetated with trees, bushes and lawn areas. There are asphalt and gravel surfaced driveway and parking areas in the southwest portion of the property. Small rockeries, about two to four feet in height, face the south and west edges of the front yard. GEOLOGIC SETTING We referred to the "Geologic Map of the Edmonds East and Part of the Edmonds West Quadrangles, Washington," by James P. Minard (1983) during our project research. The geologic map indicates that the site vicinity is underlain by Quaternary Vashon glacial till (Qgt,,). Quaternary Advance outwash (Qva) is also mapped nearby. Glacial till typically consists of a very compact, unsorted mixture of clay, silt, sand, gravel, cobbles and boulders. Advance outwash generally consists of poorly to moderated sorted, dense to very dense sand and gravel. FIELD INVESTIGATION Four test pit explorations and three infiltration test pits were completed to evaluate the subsurface soil and groundwater conditions within the property. The test pits were completed on January 24, 2022. The explorations were conducted using a client -provided excavator. The test pits extended to depths ranging from approximately 4.0 feet to about 11.0 feet below the existing ground surface. A geotechnical representative from Krazan and Associates, Inc. was present during the test pit explorations, examined the soil conditions encountered, obtained samples of the different soil types, and maintained logs of the explorations. The approximate locations of the explorations are shown on the Site Plan in Figure 2. Representative samples of the subsurface soils encountered in the geotechnical explorations at the project site were collected and sealed in plastic bags for transport to our laboratory for further observation and testing. The soils encountered in the explorations were continuously examined and visually classified in general accordance with the Unified Soil Classification System (USCS). Although our explorations did not encounter obstructions, there is the potential for obstructions such as debris, cobbles or boulders to be encountered during excavation in unexplored areas of the property. For additional information about the soils encountered, please refer to the logs of the explorations in Appendix A. Small -Scale Pilot Infiltration Test (PIT): Three (3) infiltration test pits, designated INF-1, INF-2 and INF-3, were excavated to depths between 6.0 and 11.0 feet below adjacent grade. The locations of the test pits/infiltration tests are shown on the Site Plan in Figure 2. The PITs were performed in accordance Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 4 with Volume III, Chapter 3 of the Department of Ecology (DOE) 2019 Stormwater Management Manual for Western Washington (SMMWW). The PITS were also performed in accordance with the Edmonds Stormwater Addendum (updated June 2017) Checklist 4: Methods for Determining Infiltration Rates. The infiltration tests were performed at depths of approximately 2.0 and 9.0 feet below the existing ground surface (bgs) at the time of the testing, and are noted on the attached test pit logs. The exposed test areas for each of the PITs were approximately 24 square feet for INF-1, 20 square feet for INF-2, and 15 square feet for INF-3. The infiltration tests included a pre-soak period, followed by a steady- state infiltration rate test, and then falling head infiltration rate testing. Following the infiltration tests, the test pits were advanced to depths of 6.0 and 11.0 feet bgs to examine the soil conditions below the level where the test was performed. A field engineer from Krazan and Associates was present during the exploration and testing, examined the soils and geologic conditions encountered, obtained samples of the different soil types, documented results of the infiltration testing and maintained logs of the soils exposed in the test pits. Representative samples of the subsurface soils encountered in the test pits were collected and sealed in plastic bags. These samples were transported to our laboratory for further examination and testing. The soils encountered in the exploratory test pits were continuously examined and visually classified in accordance with the Unified Soil Classification System (USCS). SOIL PROFILE AND SUBSURFACE CONDITIONS Four test pits and three infiltration test pits were excavated at the property. Brief descriptions of the subsurface conditions exposed in the test pits are included in the paragraphs below. Test Pit 1 (TP-1) was located in the northwest portion of the property. TP-1 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-1 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Test Pit 2 (TP-2) was located in the north -central portion of the property. TP-2 exposed a surficial layer of organic topsoil and forest duff extending to a depth of approximately 2.0 feet. Below the topsoil and forest duff, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 4.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-2 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.5 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 5 Test Pit 3 (TP-3) was located north of the residence, in the east -central portion of the property. TP-3 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-3 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Test Pit 4 (TP-4) was located southeast of the residence, in the southeast portion of the property. TP-4 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-4 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Infiltration Test Pit 1 (INF-1) was located west of the residence, in the south-central portion of the property. INF-1 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose gray silty sand with gravel to a depth of about 2.0 feet. We interpreted the gray silty sand with gravel to be undocumented fill. Below the undocumented fill, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 4.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, INF-1 exposed dense, gray silty sand with gravel to the depth explored of approximately 11.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Infiltration Test Pit 2 (INF-2) was located east of the western ADU, in the north -central portion of the property. INF-2 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 2.5 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, INF-2 exposed dense, olive -brown to gray silty sand with gravel to the depth explored of approximately 11.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Infiltration Test Pit 3 (INF-3) was located north of the eastern ADU, in the northeast portion of the property. INF-3 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, dark yellowish -brown sand with silt, gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, INF-3 exposed dense, Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 6 gray silty sand with gravel to the depth explored of approximately 6.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. For additional information about the soils encountered, please refer to the soil logs in Appendix A. GROUNDWATER The test pits were observed for the presence of groundwater during the test pit explorations. Soil conditions were moist. Groundwater seepage was not observed in the test pit explorations at the time of our subsurface investigation. However, it is our opinion that perched groundwater could occur on this property, especially during and after prolonged periods of wet weather. Perched water occurs when surface water infiltrates through less dense, more permeable soils and accumulates on top of a relatively low permeability soil layer. Perched water does not represent a regional groundwater "table" within the upper soil horizons. Perched water tends to vary spatially and is dependent upon the amount of rainfall. We would expect the amount of perched water to decrease during drier times of the year and increase during wetter periods. It should be recognized that groundwater elevations may fluctuate with time. The groundwater level will be dependent upon seasonal precipitation, irrigation, as well as other factors. Therefore, groundwater levels at the time of the field investigation may be different from those encountered during the construction phase of the project. The evaluation of such factors is beyond the scope of this report. GEOLOGIC HAZARDS Erosion Concern/Hazard The Natural Resources Conservation Service (MRCS) map for Snohomish County includes information regarding the erosion hazard for the site vicinity. The soil in project area is mapped as Alderwood- Urban land complex, 2 to 8 percent slopes. These soils are rated as having a moderate hazard for soil erosion when vegetation is removed. It has been our experience that the potential for soil erosion can be minimized through landscaping and surface water runoff control. Typically, erosion of exposed soils will be most noticeable during periods of rainfall and may be controlled by the use of temporary erosion control measures, such as silt fences, hay bales, mulching, control ditches or diversion trenching, and contour furrowing. Erosion control measures should be in place before the onset of wet weather. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. Seismic Hazard KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 7 The 2018 International Building Code (IBC), Section 1613.2.2, refers to Chapter 20 of ASCE 7-16 for Site Class Definitions. It is our opinion that the overall soil profile corresponds to Site Class C defined by Table 20.3-1 "Site Class Definitions," according to the ASCE 7-16 Standard. Site Class C applies to a "very dense soils and soft rock" profile. The seismic site class is based on a soil profile extending to a depth of 100 feet. The soil explorations on this site extended to a maximum depth of approximately 11.0 feet and this seismic site class designation is based on the assumption that dense to very dense conditions continue below the depth explored. We referred to the Applied Technology Council (ATC) website and 2018 IBC to obtain values for Ss, Stirs, SDs, SI, Smi, SDI, F., F,, and T. The ATC website utilizes the most updated published data on seismic conditions from the United States Geological Survey. The seismic design parameters for this site are presented in the following table: Seismic Design Parameters (Reference: 2018 IBC Section 1613.2.2, ASCE7-16, and ATC) Seismic Item Value Site Coefficient Fa 1.200 S, 1.286 SMs 1.543 SDs 1.029 Site Coefficient Fv 1.500 S1 0.453 SMI 0.679 SDI 0.453 Additional seismic considerations include liquefaction potential and amplification of ground motion by soft soil deposits. The liquefaction potential is highest for loose sand with a high groundwater table. The medium dense to dense native soils interpreted to underlie the site are considered to have a low potential for liquefaction and amplification of ground motion. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. CONCLUSIONS AND RECOMMENDATIONS General KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 8 It is our opinion from a geotechnical standpoint that the site is compatible with the proposed commercial development, provided that our recommendations are incorporated into project plans and are implemented during construction. Summary of Subsurface Conditions: Our explorations generally encountered a near surface layer of loose organic soil and undocumented fill extending to depths of about 0.5 to 2.0 feet. Beneath the surficial soils, the test pits generally exposed loose to medium dense native weathered soils, consisting of silty sand with gravel, to depths of 2.5 to 4.0 feet. Beneath the weathered horizon, the test pits exposed dense to very dense native glacial till (hardpan) consisting of silty sand with gravel. Groundwater seepage was not observed at the time of our subsurface investigation. The dense/hard soils are interpreted to be native glacially consolidated deposits, and typically have a relatively high capacity for foundation support. The undocumented fill soils are not considered suitable for foundation support. Groundwater seepage was not encountered during our field investigation. However, perched groundwater could develop on this site during or after periods of wet weather. Care should be taken to protect foundation subgrades from disturbance if groundwater or wet soils are encountered. Difficult Excavation: Dense to very dense glacial soils, which may include cobbles and boulders, are interpreted to underlie the site. We anticipate that future excavations in the glacial soils could be difficult. It might be prudent to provide contingencies in the project schedule and budget in case excavation difficulties arise during earthwork construction. Foundations: The dense glacial soils underlying the site should provide adequate load bearing capacity for the proposed commercial structures. Detailed foundation support recommendations, including a recommended allowable load bearing pressure, are included in the Foundations section of this report. The installation of foundation drains is recommended for this project. Stormwater Infiltration: The dense to very dense glacial till soil (hardpan) encountered in the test pits at this site are not considered suitable for the use of infiltration techniques for stormwater management. There is some potential for slight amounts infiltration as discussed in the Stormwater Management section of this report. Moisture Sensitive Soils: The soils encountered in our explorations on site are considered to be highly moisture -sensitive. Silty soils are typically easily disturbed and are difficult or impossible to compact in wet conditions. It will be necessary to protect exposed subgrade soil with a layer of crushed rock if Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 9 construction occurs during wet weather. The non -organic on -site soils could be used as structural fill material, provided the moisture content is near optimum and the soil could be suitably compacted to project specifications. This will depend on the moisture content of the soils at the time of construction. Krazan and Associates is available on request to evaluate the suitability of the on -site soils for use as structural fill material at the time of construction. Site Preparation General site clearing should include removal of existing structures; vegetation; trees and associated root systems; wood; abandoned structures and utilities; rubble; and rubbish. Site stripping should extend until all organics in excess of 3 percent by volume are removed. These materials will not be suitable for use as structural fill. However, stripped topsoil may be stockpiled and re -used in landscape or non- structural areas. After stripping operations, the construction areas should be inspected to identify any soft/loose areas. Any remaining soft/loose soils should be excavated to expose medium dense or firmer native soils. The resulting excavations should be filled with approved structural fill. Structural fill material should be within f 2 percent of the optimum moisture content, and the soils should be compacted to a minimum of 95 percent of the maximum dry density as determined by ASTM Test Method D 1557. During wet weather conditions, subgrade stability problems and grading difficulties may develop due to excess moisture, disturbance of sensitive soils and/or the presence of perched groundwater. Construction during the extended periods of wet weather could result in the need to remove wet disturbed soils if they cannot be suitably compacted due to elevated moisture contents. The on -site soils have significant silt content and are considered to be moisture sensitive, and can be easily disturbed when wet. If overexcavation is necessary to remove wet disturbed soil, it should be confirmed through continuous monitoring and testing by a qualified geotechnical engineer or geologist. Soils that have become unstable may require drying to near their optimal moisture content before compaction is feasible. Selective drying may be accomplished by scarifying or windrowing surficial material during extended periods of dry, warm weather (typically during the summer months). If the soils cannot be dried back to a workable moisture condition, remedial measures may be required. General project site winterization should consist of the placement of aggregate base and the protection of exposed soils during the construction phase. It should be understood that even if Best Management Practices (BMPs) are implemented and followed for wintertime soil protection there is a significant chance that mitigation of disturbed moisture sensitive soils will still be required. Any buried structures encountered during construction should be properly removed and backfilled. Excavations, depressions, or soft and pliant areas extending below the planned finish subgrade levels Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 10 should be excavated to expose firm undisturbed soil, and backfilled with structural fill. In general, any septic tanks, underground storage tanks, debris pits, cesspools, or similar structures should be completely removed from the area of the planned addition. Concrete footings should be removed to an equivalent depth of at least 3 feet below proposed footing elevations or as recommended by the geotechnical engineer. The resulting excavations should be backfilled with structural fill. A representative of our firm should be present during all site clearing and grading operations to observe, test and evaluate earthwork construction. This testing and observation are integral parts of our service, as acceptance of earthwork construction is dependent upon compaction and stability of the material. The geotechnical engineer may reject any material that does not meet compaction and stability requirements. Further recommendations, contained in this report, are predicated upon the assumption that earthwork construction will conform to the recommendations set forth in this section and in the Structural Fill section. Temporary Excavations The on -site soils may have variable cohesion strengths, therefore the safe angles to which these materials may be cut for temporary excavations is limited, as the soils may be prone to caving and slope failures in temporary excavations. Temporary excavations in the loose to medium dense soils should be no steeper than 1H:1V (Horizontal to Vertical). Depending on the groundwater conditions, flatter inclinations may be necessary. Temporary shoring may also be necessary if excavation to stable inclinations is not feasible due to the proximity to structures or property lines. We should evaluate the excavations at the time of construction. All temporary cuts should be in accordance with Washington Administrative Code (WAC) Part N, Excavation, Trenching, and Shoring. The temporary slope cuts should be visually inspected daily by a qualified person during construction work activities and the results of the inspections should be included in daily reports. The contractor is responsible for maintaining the stability of the temporary cut slopes and minimizing slope erosion during construction. The temporary cut slopes should be covered with plastic sheeting to help minimize erosion during wet weather and the slopes should be closely monitored until the permanent retaining systems are complete. Materials should not be stored and equipment operated within 10 feet of the top of any temporary cut slope. A Krazan & Associates geologist or geotechnical engineer should observe, at least periodically, the temporary cut slopes during the excavation work. The reason for this is that all soil conditions may not be fully delineated by the limited sampling of the site from the geotechnical explorations. In the case of temporary slope cuts, the existing soil conditions may not be fully revealed until the excavation work exposes the soil. Typically, as excavation work progresses the maximum inclination of the temporary slope will need to be evaluated by the geotechnical engineer so that supplemental recommendations can Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 11 be made. Soil and groundwater conditions can be highly variable. Scheduling for soil work will need to be adjustable, to deal with unanticipated conditions, so that the project can proceed smoothly and required deadlines can be met. If any variations or undesirable conditions are encountered during construction, Krazan & Associates should be notified so that supplemental recommendations can be made. Structural Fill Fill placed beneath foundations, pavement, or other settlement -sensitive structures should be placed as structural fill. Structural fill, by definition, is placed in accordance with prescribed methods and standards, and is monitored by an experienced geotechnical professional. Field monitoring procedures would include the performance of a representative number of in -place density tests to document the attainment of the desired degree of relative compaction. The area to receive the fill should be suitably prepared as described in the Site Preparation subsection of this report prior to beginning fill placement. Typically, all weather imported structural fill material should consist of well -graded gravel or sand and gravel mixture with a maximum grain size of 3 inches and less than 5 percent fines (material passing the U.S. Standard No. 200 Sieve). All structural fill material should be submitted for approval to the geotechnical engineer at least 48 hours prior to delivery to the site. Fill soils should be placed in horizontal lifts not exceeding 8 inches in thickness prior to compaction, moisture -conditioned as necessary, (moisture content of soil shall not vary by more than f2 percent of optimum moisture) and the material should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. In -place density tests should be performed on all structural fill to document proper moisture content and adequate compaction. Additional lifts should not be placed if the previous lift did not meet the compaction requirements or if soil conditions are not considered stable. Foundations Conventional shallow spread footings supported on dense native glacial soils, or on structural fill extending to the dense native glacial soils, may be designed using an allowable bearing pressure of 3,500 pounds per square foot (psf) for dead plus live loads. This value may be increased by one third for short duration loads such as wind or seismic loading. A representative of Krazan and Associates should visit the site during construction to evaluate the foundation bearing soil, evaluate structural fill subgrade preparation, and monitor structural fill placement. If loose soils or undocumented fill are exposed in the foundation subgrade, the removal of undocumented fill and placement of structural fill should extend horizontally beyond the outside edges of the footings by a distance equal to half the thickness of the structural fill layer to be placed beneath Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 12 the footing. Based on our soil explorations, we interpret the dense, native bearing soils at this site to be approximately 2.5 to 4.0 feet below the current grade. However, thicker layers of loose/soft soils, organics, debris, or undocumented fill could be encountered in unexplored areas of the site. Foundations should have a minimum embedment depth of 18 inches below pad subgrade (soil grade) or adjacent exterior grade, whichever is lower. Footing widths should be based on the anticipated loads and allowable soil bearing pressure. Footings should have a minimum width of at least 12 inches regardless of load. All loose or disturbed soil should be removed from the foundation excavation prior to placing concrete. Water should not be allowed to collect in the foundation excavations. All-weather structural fill material should consist of well -graded gravel, or sand and gravel mixture, with a maximum grain size of 3 inches and less than 5 percent fines (material passing the U.S. Standard No. 200 Sieve). All structural fill material should be submitted for approval to the geotechnical engineer at least 48 hours prior to delivery to the site. Footing excavations should be inspected to verify that the foundations will be supported on suitable soil prior to the construction of footing forms. For foundations constructed as recommended, the total settlement is not expected to exceed one -inch. Differential settlement, along a 20-foot exterior wall footing, or between adjoining column footings should be less than '/2-inch. Most settlement is expected to occur during construction, as the loads are applied. However, additional post -construction settlement may occur if the foundation soils are flooded or saturated. It should be noted that the risk of liquefaction is considered low, given the composition and density of the native, on site soils. Seasonal rainfall, water run-off, and the normal practice of watering trees and landscaping areas around the proposed structures, should not be permitted to flood and/or saturate foundation subgrade soils. To prevent the buildup of water within the footing areas, continuous footing drains (with cleanouts) should be provided at the bases of the footings. The footing drains should consist of a minimum 4-inch diameter rigid perforated PVC pipe, sloped to drain, with perforations placed near the bottom and enveloped by one -inch sized washed rock in all directions and wrapped with filter fabric to reduce the migration of silt and clay into the drain. Resistance to lateral footing displacement can be computed using an allowable friction factor of 0.40 acting between the bases of foundations and the supporting subgrade. Lateral resistance for footings can also be developed using an allowable equivalent fluid passive pressure of 300 pounds per cubic foot (pcf) acting against the appropriate vertical footing faces (neglecting the upper 12 inches of soil). The allowable friction factor and allowable equivalent fluid passive pressure values include a factor of safety of 1.5. The frictional and passive resistance of the soil may be combined without reduction in determining the total lateral resistance. A 1/3 increase in the above values may be used for short duration, wind and seismic loads. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. Floor Slabs and Exterior Flatwork KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 13 For building floor slab subgrades prepared in accordance with the recommendations presented in the Site Preparation section of this report, floor slabs may be designed using a modulus of subgrade reaction value of k = 200 pounds per cubic inch (pci) for slabs supported on medium dense or firmer native soils or on structural fill extending to medium dense or firmer native soil. In areas where it is desired to reduce floor dampness, such as areas covered with moisture sensitive floor coverings, we recommend that concrete slab -on -grade floors be underlain by a water vapor retarder system. The water vapor retarder should consist of a vapor retarder sheeting underlain by a minimum of 4-inches of compacted clean (less than 5 percent passing the U.S. Standard No. 200 Sieve), open -graded coarse rock of 3/4-inch maximum size. The vapor retarder sheeting should be protected from puncture damage. It is recommended that the utility trenches within the structures be compacted, as specified in our report, to minimize the transmission of moisture through the utility trench backfill. Special attention to the immediate drainage and irrigation around the buildings is recommended. Positive drainage should be established away from the structures and should be maintained throughout the lives of the structures. Water should not be allowed to collect adjacent to the structures. Over -irrigation within landscaped areas adjacent to the structures should not be performed. In addition, ventilation of the structures may be prudent to reduce the accumulation of interior moisture. LATERAL EARTH PRESSURES AND RETAINING WALLS We have developed criteria for the design of retaining or below grade walls. Our design parameters are based on retention of the in -place soils or structural fill. The parameters are also based on level, well - drained wall backfill conditions. Walls may be designed as "restrained" retaining walls based on "at - rest" earth pressures, plus any surcharge on top of the walls as described below, if the walls are braced to restrain movement and/or movement is not acceptable. Unrestrained walls may be designed based on "active" earth pressure, if the walls are not part of the buildings and some movement of the retaining walls is acceptable. Acceptable lateral movement equal to at least 0.2 percent of the wall height would warrant the use of "active" earth pressure values for design. The following table, titled Wall Design Criteria, presents the recommended soil related design parameters for retaining walls with well -drained level backfill. Wall Design Criteria "At -rest" Conditions (Lateral Earth Pressure) 55 pcf (Equivalent Fluid Density) (Triangular Distribution) Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 14 "Active" Conditions (Lateral Earth Pressure) 35 pcf (Equivalent Fluid Density) (Triangular Distribution Seismic Increase for "Active" Conditions 7 psf x H (Uniform Distribution) (Lateral Earth Pressure) Where H is the height of the wall in feet Passive Earth Pressure on Low Side of Wall Neglect upper one -foot, then 300 pcf (includes factor of safety of 1.5) (Equivalent Fluid Density) Soil -Footing Coefficient of Sliding Friction 0.4 includes factor of safety of 1.5 The stated lateral earth pressures do not include the effects of hydrostatic pressure generated by water accumulation behind the retaining walls or loads imposed by construction equipment, foundations or roadways adjacent to the wall (surcharge loads). To minimize the lateral earth pressure and prevent the buildup of water pressure against the walls, continuous footing drains (with cleanouts) should be provided at the bases of the walls. The footing drains should consist of a minimum 4-inch diameter rigid PVC perforated pipe, sloped to drain, with perforations placed near the bottom. The drainpipe should be enveloped by 6 inches of washed gravel in all directions wrapped in filter fabric to prevent the migration of silt and clay into the drain. The wall fill material adjacent to and extending a lateral distance of at least 2 feet behind the walls should consist of free -draining granular material. All free -draining backfill should contain less than 3 percent fines (passing the U.S. Standard No. 200 Sieve) based upon the fraction passing the U.S. Standard No. 4 Sieve with at least 30 percent of the material being retained on the U.S. Standard No. 4 Sieve. Alternatively, a drainage composite may be used. It should be realized that the primary purpose of the free -draining material is the reduction of hydrostatic pressure. Some potential for the moisture to contact the back face of the wall may exist, even with treatment, which may require that more extensive waterproofing be specified for walls, which require interior moisture sensitive finishes. We recommend that the wall fill be compacted to at least 95 percent of the maximum dry density based on ASTM D1557 Test Method. In -place density tests should be performed to verify adequate compaction. Soil compactors place transient surcharges on the backfill. Consequently, only light hand operated equipment is recommended for fill compaction within 3 feet of walls so that excessive stress is not imposed on the walls. Stormwater Management This investigation included an evaluation of the feasibility of stormwater infiltration for this project. The dense to very dense glacial till soil (hardpan) encountered in the test pits at this site are not considered suitable for the use of infiltration techniques for stormwater management. As requested by Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 15 the project civil engineer, three small-scale Pilot Infiltration Tests (PITS) were conducted at the site. The PIT results indicted some potential for slight amounts infiltration may be feasible for use in conjunction with the design of other stormwater management systems. Stormwater Infiltration Rate — Small Scale "PIT" Method: A bio-retention swale was being considered as a part of the stormwater management system for this project. Drainage plans were not available at the time this letter was prepared. The design infiltration rate has been developed based on procedures outlined in the EMC Chapter 18.30 and the Edmonds Stormwater Addendum, as well as Volume III of the Washington State Department of Ecology's "Stormwater Management Manual for Western Washington," (SMMWW, 2014 & updated 2019). Three small-scale stormwater Pilot Infiltration Tests (PIT) were performed at the property to evaluate the stormwater infiltration rate. The PIT method for evaluating the stormwater infiltration rate of the site soils generally includes an excavation, with an area of at least 12 square feet, in the area of the proposed infiltration system. The PITs were performed between depths of 2.0 and 9.0 feet below the current grade in the areas shown on the site plan in Figure 2. The bottom of the excavations for the small-scale PITs exposed test areas of approximately 15, 20 and 24 square feet. Data analysis included correction factors to determine the long-term or corrected infiltration rate. The applied correction factors were as follows: • Site Variability, CFv = 0.33 • Test Method, CFt = 0.5 • Degree of Influent, CFm = 0.9 In our opinion, a design infiltration rate of 0.2-inch per hour should be appropriate provided that pretreatment measures for control of total suspended solids are adequately maintained. The native sand and gravel materials were exposed between depths of 0.5 and 2.0 feet in the test pits. Changes in soil conditions and the corresponding infiltration rate are possible at different locations and depths. Accordingly, we recommend that the subsurface soils be evaluated during construction by a representative of the geotechnical engineer. Construction equipment should not be allowed on the soils at the base of the infiltration areas, as compaction of the soils may reduce their permeability. Bioretention Swale: We understand that a bioretention Swale is being considered for stormwater management for this project. The Swale would be located in an area between the east wall of the planned buildings and the east property line. The City of Edmonds Stormwater Addendum Checklist 10, item 23, indicates that, "If the contributing area is less than 5,000 square feet, the bioretention area Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 16 should be at least 5 feet from a structure without a basement and 10 feet from a structure with a basement." We understand that the proposed buildings will not have basements, and in our opinion, the separation between the high-water elevation of the proposed bioretention swale and the building may be reduced to 3 feet, provided the high-water elevation in the bioretention Swale is at least one -foot below the building's bottom of footing elevation. Organic Content Our laboratory in Lynnwood performed the organic content testing on selected soil samples based on ASTM D-2974. Organic content is one factor used to determine if the soil type has the potential to filter stormwater runoff. According to the SMMWW, the minimum useful organic content for filtrations is 1.0 percent. The test results for the soil samples are presented in Table 1. Table 1: Organic Content Test Pit Number Sample Depth (feet) Soil Classification Organic Content (percent) INF-2 9.0 Gray Silty Sand with Gravel 0.6 INF-3 2.0 Brown Silty Sand with Gravel and Trace Organics 2.4 Cation Exchange Capacity Cation Exchange Capacity (CEC) refers to the ability of soil to hold cation nutrients. Different soil types have different CEC values. In general, clay, silt and organic matter tend to have higher CEC values than sand and gravel. CEC is typically measured in millequivalents (meq). Stormwater system designers often use the CEC information to determine if the on -site soils have the potential to filter or clean stormwater runoff. According to the SMMWW, the minimum useful CEC is 5.0 meq/100g dry soil. Soil samples from Infiltration Test Pits INF-2 and INF-3 were processed by KTL (KUO Testing Labs) in Othello, WA for Cation Exchange Capacity determination. The CEC test results are presented below in Table 2. Detailed test results information from KUO Testing Labs is attached to this report. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 17 Table 2: Cation Exchange Capacity Test Pit Number Sample Depth Soil Classification Cation Exchange (feet) Capacity (meq) INF-2 9.0 Gray Silty Sand with 2.2 Gravel INF-3 2.0 Brown Silty Sand with 5.5 Gravel and Trace Organics Erosion and Sediment Control Erosion and sediment control (ESC) is used to minimize the transportation of sediment to wetlands, streams, lakes, drainage systems, and adjacent properties. Erosion and sediment control measures should be taken and these measures should be in general accordance with local regulations. As a minimum, the following basic recommendations should be incorporated into the design of the erosion and sediment control features of the site: 1) Phase the soil, foundation, utility and other work, requiring excavation or the disturbance of the site soils, to take place during the dry season (generally May through September). However, provided precautions are taken using Best Management Practices (BMP's), grading activities can be undertaken during the wet season (generally October through April), but it should also be known that this may increase the overall cost of the project. 2) All site work should be completed and stabilized as quickly as possible. 3) Additional perimeter erosion and sediment control features may be required to reduce the possibility of sediment entering the surface water. This may include additional silt fences, silt fences with a higher Apparent Opening Size (AOS), construction of a berm, or other filtration systems. 4) Any runoff generated by dewatering discharge should be treated through construction of a sediment trap if there is sufficient space. If space is limited, other filtration methods will need to be incorporated. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. Groundwater Influence on Structures and Earthwork Construction KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 18 Groundwater seepage was not encountered in the test pits extending to 11.0 feet below the surface during our exploration of this site. However, it is our opinion that perched groundwater could occur on this property, especially during and after prolonged periods of wet weather. It should be recognized that groundwater elevations may fluctuate with time. If groundwater is encountered during construction, we should observe the conditions to determine if dewatering will be needed. Design of temporary dewatering systems to remove groundwater should be the responsibility of the contractor. Care should be taken to protect foundation subgrades from disturbance when groundwater or wet soils are encountered. If earthwork is performed during or soon after periods of precipitation, the subgrade soils may become saturated. These soils may "pump," and the materials may not respond to densification techniques. Typical remedial measures include: disking and aerating the soil during dry weather; mixing the soil with drier materials; removing and replacing the soil with an approved fill material. A qualified geotechnical engineering firm should be consulted prior to implementing remedial measures to observe the unstable subgrade conditions and provide appropriate recommendations. Drainage and Landscaping The ground surface should slope away from building pads and pavement areas, toward appropriate drop inlets or other surface drainage devices. It is recommended that adjacent exterior grades be sloped a minimum of 2 percent for a minimum distance of 5 feet away from structures. We recommend the installation of foundation drains with cleanouts for this project. The foundation drains should consist of a minimum 4-inch diameter perforated pipe, sloped to drain, with perforations placed down and enveloped by 6 inches of washed gravel in all directions and filter fabric to limit the migration of silt and clay into the drains. Roof drains should be tightlined away from the foundations. Roof drains should not be connected to the foundation drains. Subgrade soils in pavement areas should be inclined at a minimum of 1 percent and drainage gradients should be maintained to carry all surface water to collection facilities, and suitable outlets. These grades should be maintained for the life of the development. Specific recommendations for and design of storm water disposal systems are beyond the scope of our services and should be prepared by other consultants that are familiar with design and discharge requirements. Utility Trench Backfill Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 19 Utility trenches should be excavated according to accepted engineering practices following OSHA (Occupational Safety and Health Administration) standards, by a contractor experienced in such work. The responsibility for the safety of open trenches should be borne by the contractor. Traffic and vibration adjacent to trench walls should be minimized; cyclic wetting and drying of excavation side slopes should be avoided. Depending upon the location and depth of some utility trenches, groundwater flow into open excavations could be experienced, especially during or shortly following periods of precipitation. All utility trench backfill should consist of structural fill. Utility trench backfill placed in or adjacent to buildings and exterior slabs should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. The upper 5 feet of utility trench backfill placed in pavement areas should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. Below 5 feet, utility trench backfill in pavement areas should be compacted to at least 90 percent of the maximum dry density based on ASTM Test Method D1557. Pipe bedding should be in accordance with the pipe manufacturer's recommendations. The contractor is responsible for removing all water -sensitive soils from the trenches regardless of the backfill location and compaction requirements. The contractor should use appropriate equipment and methods to avoid damage to the utilities and/or structures during fill placement and compaction. Testing and Inspection A representative of Krazan & Associates, Inc. should be present at the site during the earthwork activities to confirm that actual subsurface conditions are consistent with the exploratory fieldwork. This activity is an integral part of our services as acceptance of earthwork construction is dependent upon compaction testing and stability of the material. This representative can also verify that the intent of these recommendations is incorporated into the project design and construction. Krazan & Associates, Inc. will not be responsible for grades or staking, since this is the responsibility of the Prime Contractor. Furthermore, Krazan & Associates is not responsible for the contractor's procedures, methods, scheduling or management of the work site. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. LIMITATIONS KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 20 Geotechnical engineering is one of the newest divisions of Civil Engineering. This branch of Civil Engineering is constantly improving as new technologies and understanding of earth sciences improves. Although your site was analyzed using the most appropriate current techniques and methods, undoubtedly there will be substantial future improvements in this branch of engineering. In addition to improvements in the field of geotechnical engineering, physical changes in the site either due to excavation or fill placement, new agency regulations or possible changes in the proposed structure after the time of completion of the soils report may require the soils report to be professionally reviewed. In light of this, the owner should be aware that there is a practical limit to the usefulness of this report without critical review. Although the time limit for this review is strictly arbitrary, it is suggested that two years be considered a reasonable time for the usefulness of this report. Foundation and earthwork construction are characterized by the presence of a calculated risk that soil and groundwater conditions have been fully revealed by the original foundation investigation. This risk is derived from the practical necessity of basing interpretations and design conclusions on limited sampling of the earth. Our report, design conclusions and interpretations should not be construed as a warranty of the subsurface conditions. Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. The recommendations made in this report are based on the assumption that soil conditions do not vary significantly from those disclosed during our field investigation. The findings and conclusions of this report can be affected by the passage of time, such as seasonal weather conditions, manmade influences, such as construction on or adjacent to the site, natural events such as earthquakes, slope instability, flooding, or groundwater fluctuations. If any variations or undesirable conditions are encountered during construction, the geotechnical engineer should be notified so that supplemental recommendations can be made. The conclusions of this report are based on the information provided regarding the proposed construction. If the proposed construction is relocated or redesigned, the conclusions in this report may not be valid. The geotechnical engineer should be notified of any changes so that the recommendations can be reviewed and reevaluated. Misinterpretations of this report by other design team members can result in project delays and cost overruns. These risks can be reduced by having Krazan & Associates, Inc. involved with the design teams' meetings and discussions after submitting the report. Krazan & Associates, Inc. should also be retained for reviewing pertinent elements of the design team's plans and specifications. Contractors can also misinterpret this report. To reduce this, risk Krazan & Associates. Inc. should participate in pre -bid and preconstruction meetings, and provide construction observations during the site work. This report is a geotechnical engineering investigation. The scope of our services did not include any environmental site assessment for the presence or absence of hazardous and/or toxic materials in the soil, Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 21 groundwater or atmosphere, or the presence of wetlands. Any statements or absence of statements, in this report or on any soils log regarding odors, unusual or suspicious items, or conditions observed are strictly for descriptive purposes and are not intended to convey engineering judgment regarding potential hazardous and/or toxic assessments. The geotechnical information presented herein is based upon professional interpretation utilizing standard engineering practices and a degree of conservatism deemed proper for this project. It is not warranted that such information and interpretation cannot be superseded by future geotechnical developments. We emphasize that this report is valid for this project as outlined above, and should not be used for any other site. Our report is prepared for the exclusive use of our client. No other party may rely on the product of our services unless we agree in advance to such reliance in writing. CLOSURE If you have any questions, or if we may be of further assistance, please do not hesitate to contact our office at (425) 485-5519. Respectfully submitted, KRAZAN & ASSOCIATES, INC. Michael D Rundquist, PE Senior Project Manager MDR 02/04/2022 Krazan & Associates, Inc. Offices Serving The Western United States Vicinity Map N (Not to Scale) 196TH ST SW t Z 524� I j 524 �'rrll�i r Edmonds 200TH ST SW Community Coll -Central 200TH ST SW Al, +Nasl ingto A Univ 202NO ST SW 10ITH ST SW Cedar 3 Approximate t Valley W z II Site Area Seattle a �,�•1 �.� 20BTH ST Sw °t 21orH sr sw ri,+rr 3 L+ki w 12TH ST SW - t 3 Z � I W Q 3 x e o j I © 216TH ST SW 2: N 218TH ST SW north ST SW 3FT —C'husc Z 3 —Luke = a t 224TH ST SW — SW 3 0 sper , e 226TH PL SW Q 3 3 —w w ik 228TH'ST•SW $ o j i 230TH ST,sW 4 Y W A 3 7509 212th St SW, Edmonds, WA Reference: The Vicinity Map is based on the USGS topographic map titled, i"Edmonds East Quadrangle - Washington - 7.5-min Series", dated 2017. �I�alZ & ASSOCIATES,INC. Glacier Offices and Warehouse - 7509 212th St SW, Edmonds, WA Date: January 2022 Project Number: 092-22001 Drawn By: NG Figure 1 Not to scale Site Plan N (Not to Scale) ---------------- -------------------------- I TP-2 I I _____ Gra_1[Ql---------- I Asphalt f Jy TP-1 Trash Area I Proposed Outdoor I Storage I (Future Addition) I INF-2 I I Proposed 1-Story Warehouse I Building I I TP_3 00 I a, C I I m D L7 I INF-1 I I Proposed I 2-Story I I Office , Building I ; ; TP-4 I I ; 212th St SW Reference: The site plan is based on the preliminary site plan titled, LEGEND"Glacier Environmental Services New Construction" by TG Architect dated 12/30/21. TP-1 1<1:-az;arl& s S C 1 T E S, 1 N C. Number and Approximate L� L� Location of Test Pit INF-1 Glacier Offices and Warehouse - 7509 212th St SW, Edmonds, WA Number and Approximate "PIT' Locations of Small Scale Date: January 2022 Project Number: 092-22001 -------- Approximate Property Line Drawn By: NG Figure 2 Not to scale APPENDIX A FIELD INVESTIGATION AND LABORATORY TESTING Field Investigation The field investigation consisted of a surface reconnaissance and a subsurface exploration program. Four (4) test pits and three (3) infiltration test pits were excavated, performed and sampled at the property for the subsurface exploration at this site. The test pits explorations were excavated to depths ranging from approximately 4.0 feet to 11.0 feet below the existing ground surface using a trackhoe excavator provided by the client. Locations of the soil explorations are shown on the Site Plan in Figure 2. The depths shown on the attached soil logs are from the existing ground surface at the time of the explorations. The soils encountered were logged in the field during the subsurface exploration and, with supplementary laboratory test data, are described in accordance with the Unified Soil Classification System (USCS). All samples from the explorations were returned to our laboratory for evaluation. The logs of the soil explorations along with the laboratory test results are presented in this appendix. Laboratory Testing The laboratory testing program was developed primarily to determine the physical characteristics of the soils. Test results were used for soil classification and as criteria for determining the engineering suitability of the subsurface materials encountered. Krazan and Associates, Inc. Offices Serving The Western United States Soil Classification USCS Soil Classification Major Division Group Description Coarse- Grained Soils Gravel and Gravelly Soils < 50% coarse fraction passes #4 sieve Gravel (with little or no fines) GW Well -Graded Gravel GP Poorly Graded Gravel Gravel (with > 12% fines) GM Silty Gravel GC Clayey Gravel < 50% passes #200 sieve Sand and Sandy Soils > 50% coarse fraction passes #4 sieve Sand (with little or no fines) SW Well -Graded Sand SP Poorly Graded Sand Silty Sand Sand (with > 12% fines) SM SC Clayey Sand Fine- Grained Soils Silt and Clay Liquid Limit < 50 ML Silt CL Lean Clay OL Organic Silt and Clay (Low Plasticity) > 50% passes #200 sieve Silt and Clay Liquid Limit > 50 MH Inorganic Silt CH Inorganic Clay OH Organic Clay and Silt (Med. to High Plasticity) Highly Organic Soils PT Peat Relative Density with Respect to SPT N-Value Coarse -Grained Soils Fine -Grained Soils Density N-Value (Blows/Ft) Density N-Value (Blows/Ft) Very Loose 0-4 Very Soft 0-1 Loose 5 -10 Soft 2-4 Medium Dense 11 - 30 Medium Stiff 5-8 Dense 31 -50 Stiff 9 - 15 Very Dense > 50 Very Stiff 16 - 30 Hard > 30 LOG OF EXPLORATORY TEST PIT INF-1 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: -390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 t-- -t Topsoil P - - - -------------------------------------------------------------------------------------------------------------------------- Gray Silty Sand with Gravel 1 (Moist, Loose)(Undocumented Fill) 2 Brown Silty Sand with Gravel and Trace Organics (SM) (Moist, Loose to Medium Dense)(Native Weathered Soils) 1 G 3 ' Gray Silty Sand with Gravel (SM) (Moist, Dense)(Native Glacial Soils) is 2 G 6 is 3 G 8 is 9 - Small Scale "PIT" Depth - 4 G 10 End of Exploratory Test Pit 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT INF- KR z N AND ASSOCIATES, INC. PROJECT: Glr ofies&Aareh_se DATE: e/42/22 PROJECT NO:m2- 001PAGE: 1g1 CONTRACTOR: Glacier Environmental SURFaE ELEV.: -3K' SAMPLE METHomo Grab LOCATION: Edmonds, AA Natural Moisture Content and a!lerberg Limb ¢ MATERIAL DESCRIPTION ) CL mea Moisture bps, F > w ) o m. Content Limit IL a Lu § k k k q m y 3 #k Topsoil �ma ------ — — — — — — — — — — — — — — — — — — — — — —-----c- ---- • Brown &lylSand with Gravel and Trace Organics (S9) G I. (9dkLoose to Medium Dns)(NkvWeathered Soils) 2 ... ... ... ------------------------------------------------------------------------------------------------------------------------------------------- Olive-Brown Sly! Sand with Gravel and Trace Omani (S9) as a\ (9dkDmm)(N+m Glacial Soils) 2 � 4 \\} 5 \\\ 8 \\\ 7 \\/ a \ /\\ Soil becomes gray. \\ is g ITG _Small Scale ?I2 Depth - 3 1O \\\ En ¥ Exploratory Test m! 12 1a Aa ray. ¥m» 2 Fier! Water Observaea:Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT INF-3 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: —390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu _j _j Limit Content Limit w W a a o? N N 10 30 50 70 t-- -t Topsoil To p - - - -- -- - -- - - - - -- -- -- -- -- - - -------------------------------------------------------------------------------- Dark Yellowish -Brown Sand with Silt, Gravel and Trace Organics I. (SP SM) (Moist, Loose to Medium Dense)(Native Weathered Soils) . 9.1 2 Small Scale "PIT" Depth - 1 G 2G Gray Silty � Sand with Gravel SM) (Moist, Dense)(Native Glacial Soils) 4 6 End of Exploratory Test Pit 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-1 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: -390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil -- -- -- -- - - -- -- - - ---------------------------------------------------------------------------------------------------- " Brown Silty Sand with Gravel and Trace Organics (SM) 1 I. (Moist, Loose to Medium Dense)(Native Weathered Soils) ------------------------------------------------------------------------------------------------------------------------------------------ Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-2 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: -390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J J W W n, m W MATERIAL DESCRIPTION Z Plastic Moisture Liquid _ > -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil and Forest Duff --------------------------------------------------------------------------------------------------------------------------------------- Brown Silty Sand with Gravel and Trace Organics (SM) 1 G (Moist, Loose to Medium Dense)(Native Weathered Soils) 3 ' Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-3 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: -390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil -- -- -- -- - - -- -- - - ---------------------------------------------------------------------------------------------------- " Brown Silty Sand with Gravel and Trace Organics (SM) 1 I. (Moist, Loose to Medium Dense)(Native Weathered Soils) 1 G Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-4 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: -390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil -- -- -- -- - - -- -- - - ---------------------------------------------------------------------------------------------------- " Brown Silty Sand with Gravel and Trace Organics (SM) 1 I. (Moist, Loose to Medium Dense)(Native Weathered Soils) ------------------------------------------------------------------------------------------------------------------------------------------ Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- KRAZAN & ASSOCIATES, INC. TEST REPORT (Page 1 of 1) Job Name: Glacier Office & Warehouse Job # : 092-22001 Glacier Enviromental Services, Inc. 1 /25/2022 Laboratory Determination of Water (Moisture) Content of Soils by Mass (ASTM D-2216) Sample ID Sample Description Boring / Test Pit Depth Wet & Tare Dry &Tare Tare Results 77382-A Brown silty sand with gravel and trace of organics INF-2 0.5' 1148.0 1059.4 202.9 10.3% 77382-B Olive -brown silty sand with gravel and trace of organics INF-2 3.0' 1265.3 1178.2 174.7 8.7% 77382-C Gray silty sand with gravel INF-2 9.0' 1089.7 1012.1 173.3 9.3% 77382-D Dark yellowish -brown poorly graded sand with silt, gravel and trace of organics INF-3 2.0' 1009.4 942.6 206.3 9.1% Tested By: Cole Demas Checked By: Corbett Mercer (Lab Manager) Revision 3 1 /21 /09 X W Z Z W U Of W 0- 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ o00 N M T- --F-- T--7-M I i 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 6.5 17.1 10.2 17.7 27.8 20.7 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1.5 100.0 1 95.2 .75 93.5 .5 83.9 .375 79.9 #4 76.4 #10 66.2 #20 57.6 #40 48.5 #60 37.4 #100 28.7 #200 20.7 Material Description Brown silty sand with gravel and trace of organics. Atterberg Limits (ASTM D 4318) PL= NP LL= NV Pl= NP Classification USCS (D 2487)= SM AASHTO (M 145)= A-1-b Coefficients D90= 16.0947 D85= 13.2939 D60= 1.0906 D50= 0.4629 D80= 0.1645 D15= D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 10.3% Date Received: 1/25/2022 Date Tested: 1/27/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-2 Date Sampled: 1/25/2022 Sample Number: 77382-A Depth: 0.5' Client: Glacier Environmental Services, Inc. J<X Project: Glacier Office & Warehouse .�� !Y W Z Z W U IY W d 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ o00 N M vi� i i i i i 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 10.4 20.3 12.4 17.0 25.7 14.2 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1.5 100.0 1.25 92.6 1 89.6 .75 89.6 .5 81.8 .375 79.0 .25 73.9 #4 69.3 #10 56.9 #20 48.8 #40 39.9 #60 29.0 #100 20.9 #200 14.2 Material Description Olive -brown silty sand with gravel and trace of organics. Atterberg Limits (ASTM D 4318) PL= NP LL= NV PI= NP Classification USCS (D 2487)= SM AASHTO (M 145)= A-1-b Coefficients D90= 27.5511 D85= 14.8273 D60= 2.5632 D50= 0.9679 D80= 0.2629 D15= 0.0822 D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 8.7% Date Received: 1/25/2022 Date Tested: 1/27/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-2 Date Sampled: 1/25/2022 Sample Number: 77382-B Depth: 3.0' Client: Glacier Environmental Services, Inc. Project: Glacier Office &Warehouse J<X . X W Z Z W U IY W d 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ ... N M V (D � � N f0 M N n M # # # # # # # # # i i i 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 1.5 16.9 6.7 19.3 37.5 18.1 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1 100.0 .75 98.5 .5 91.3 .375 88.8 .25 84.1 #4 81.6 #10 74.9 #20 67.1 #40 55.6 #60 40.0 #100 27.7 #200 18.1 Material Description Gray silty sand with gravel Atterbera Limits (ASTM D 4318 PL= NP LL= NV PI= NP Classification USCS (D 2487)= SM AASHTO (M 145)= A-2-4(0) Coefficients D90= 11.1440 D85= 6.8454 D60= 0.5200 D50= 0.3478 D30= 0.1684 D15= D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 9.3% Organic Content of Soils (ASTM D-2974): 0.6% Date Received: 1/25/2022 Date Tested: 1/28/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-2 Date Sampled: 1/25/2022 Sample Number: 77382-C Depth: 9.0' Client: Glacier Environmental Services, Inc. Project: Glacier Office &Warehouse J<X . !Y W Z Z W U Of W 0- 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ o00 N M 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 14.8 19.6 7.4 16.1 30.1 12.0 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1.5 100.0 1 94.6 .75 85.2 .5 77.2 .375 73.5 .25 69.1 #4 65.6 #10 58.2 #20 51.3 #40 42.1 #60 29.0 #100 19.1 #200 12.0 Material Description Dark yellowish -brown poorly graded sand with silt, gravel and trace of organics Atterberg Limits (ASTM D 4318) PL= NP LL= NV Pl= NP Classification USCS (D 2487)= SP-SM AASHTO (M 145)= A-1-b Coefficients D90= 21.9789 D85= 18.9524 D60= 2.5675 D50= 0.7415 D80= 0.2603 D15= 0.1061 D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 9.1% Organic Content of Soils (ASTM D-2974): 2.4% Date Received: 1/25/2022 Date Tested: 1/28/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-3 Date Sampled: 1/25/2022 Sample Number: 77382-D Depth: 2.0' Client: Glacier Environmental Services, Inc. J<X Project: Glacier Office & Warehouse .�� Report Date: February 3, 2022 Report No: 84664 Client: Krazan & Associates, Inc. Sampler: Corbett Mercer Project: Glacier Office Field: P.N.: 092-22001 - 2022 Control Samples Sampled: 1 /25/2022 k1rfrL KIJOTESTI NG LABS A Matrix Sciences Company SOIL ANALYSIS REPORT Lab # Depth Field Sample CEC Inches ID ID Meq/ Start End 1000 9451 9452 77382-C (INF-2 @ 9') 77382-D (INF-3 @ 2') Main Office: 119 E Main St., Othello, WA 99344 Oregon Office: 1300 Sixth St., Suite J, Umatilla, OR 97882 Pasco Office: 1320 E Spokane St., Pasco, WA 99301 to (509) 488-0112 ® info@kuotestinglabs.com 2.2 5.5 APPENDIX B EARTHWORK SPECIFICATIONS GENERAL When the text of the report conflicts with the general specifications in this appendix, the recommendations in the report have precedence. SCOPE OF WORK: These specifications and applicable plans pertain to and include all earthwork associated with the site rough grading, including but not limited to the furnishing of all labor, tools, and equipment necessary for site clearing and grubbing, stripping, preparation of foundation materials for receiving fill, excavation, processing, placement and compaction of fill and backfill materials to the lines and grades shown on the project grading plans, and disposal of excess materials. PERFORMANCE: The Contractor shall be responsible for the satisfactory completion of all earthwork in accordance with the project plans and specifications. This work shall be inspected and tested by a representative of Krazan and Associates, Inc., hereinafter known as the Geotechnical Engineer and/or Testing Agency. Attainment of design grades when achieved shall be certified to by the project Civil Engineer. Both the Geotechnical Engineer and Civil Engineer are the Owner's representatives. If the contractor should fail to meet the technical or design requirements embodied in this document and on the applicable plans, he shall make the necessary readjustments until all work is deemed satisfactory as determined by both the Geotechnical Engineer and Civil Engineer. No deviation from these specifications shall be made except upon written approval of the Geotechnical Engineer, Civil Engineer or project Architect. No earthwork shall be performed without the physical presence or approval of the Geotechnical Engineer. The Contractor shall notify the Geotechnical Engineer at least 2 working days prior to the commencement of any aspect of the site earthwork. The Contractor agrees that he shall assume sole and complete responsibility for job site conditions during the course of construction of this project, including safety of all persons and property; that this requirement shall apply continuously and not be limited to normal working hours; and that the Contractor shall defend, indemnify and hold the Owner and the Engineers harmless from any and all liability, real or alleged, in connection with the performance of work on this project, except for liability arising from the sole negligence of the Owner of the Engineers. TECHNICAL REQUIREMENTS: All compacted materials shall be densified to a density not less than 95 percent of maximum dry density as determined by ASTM Test Method D1557 as specified in the technical portion of the Geotechnical Engineering Report. The results of these tests and compliance with these specifications shall be the basis upon which satisfactory completion of work will be judged by the Geotechnical Engineer. SOIL AND FOUNDATION CONDITIONS: The Contractor is presumed to have visited the site and to have familiarized himself with existing site conditions and the contents of the data presented in the soil report. The Contractor shall make his own interpretation of the data contained in said report, and the Contractor shall not be relieved of liability under the contractor for any loss sustained as a result of any variance between conditions indicated by or deduced from said report and the actual conditions encountered during the progress of the work. Krazan and Associates, Inc. Offices Serving The Western United States DUST CONTROL: The work includes dust control as required for the alleviation or prevention of any dust nuisance on or about the site or the borrow area, or off -site if caused by the Contractor's operation either during the performance of the earthwork or resulting from the conditions in which the Contractor leaves the site. The Contractor shall assume all liability, including Court costs of codefendants, for all claims related to dust or windblown materials attributable to his work. SITE PREPARATION Site preparation shall consist of site clearing and grabbing and preparations of foundation materials for receiving fill. CLEARING AND GRUBBING: The Contractor shall accept the site in this present condition and shall demolish and/or remove from the area of designated project earthwork all structures, both surface and subsurface, trees, brush, roots, debris, organic matter, and all other matter determined by the Geotechnical Engineer to be deleterious. Such materials shall become the property of the Contractor and shall be removed from the site. Tree root systems in proposed building areas should be removed to a minimum depth of 3 feet and to such an extent which would permit removal of all roots larger than 1 inch. Tree root removed in parking areas may be limited to the upper P/2 feet of the ground surface. Backfill or tree root excavation should not be permitted until all exposed surfaces have been inspected and the Geotechnical Engineer is present for the proper control of backfill placement and compaction. Burning in areas, which are to receive fill materials, shall not be permitted. SUBGRADE PREPARATION: Surfaces to receive Structural fill shall be prepared as outlined above, excavated/scarified to a depth of 12 inches, moisture -conditioned as necessary, and compacted to 95 percent compaction. Loose and/or areas of disturbed soils shall be moisture conditioned and compacted to 95 percent compaction. All ruts, hummocks, or other uneven surface features shall be removed by surface grading prior to placement of any fill material. All areas which are to receive fill materials shall be approved by the Geotechnical Engineer prior to the placement of any of the fill material. EXCAVATION: All excavation shall be accomplished to the tolerance normally defined by the Civil Engineer as shown on the project grading plans. All over excavation below the grades specified shall be backfilled at the Contractor's expense and shall be compacted in accordance with the applicable technical requirements. FILL AND BACKFILL MATERIAL: No material shall be moved or compacted without the presence of the Geotechnical Engineer. Material from the required site excavation may be utilized for construction site fills provided prior approval is given by the Geotechnical Engineer. All materials utilized for constructing site fills shall be free from vegetable or other deleterious matter as determined by the Geotechnical Engineer. PLACEMENT, SPREADING AND COMPACTION: The placement and spreading of approved fill materials and the processing and compaction of approved fill and native materials shall be the responsibility of the Contractor. However, compaction of fill materials by flooding, ponding, or jetting shall not be permitted unless specifically approved by local code, as well as the Geotechnical Engineer. Both cut and fill shall be surface compacted to the satisfaction of the Geotechnical Engineer prior to final acceptance. Krazan and Associates, Inc. Offices Serving The Western United States SEASONAL LIMITS: No fill material shall be placed, spread, or rolled while it is frozen or thawing or during unfavorable wet weather conditions. When the work is interrupted by heavy rains, fill operations shall not be resumed until the Geotechnical Engineer indicates that the moisture content and density of previously placed fill are as specified. Krazan and Associates, Inc. Offices Serving The Western United States Appendix C Page C. APPENDIX C PAVEMENT SPECIFICATIONS 1. DEFINITIONS — The term "pavement' shall include asphalt concrete surfacing, untreated aggregate base, and aggregate subbase. The term "subgrade" is that portion of the area on which surfacing, base, or subbase is to be placed. 2. SCOPE OF WORK — This portion of the work shall include all labor, materials, tools and equipment necessary for and reasonable incidental to the completion of the pavement shown on the plans and as herein specified, except work specifically noted as "Work Not Included." 3. PREPARATION OF THE SUBGRADE — The Contractor shall prepare the surface of the various subgrades receiving subsequent pavement courses to the lines, grades, and dimensions given on the plans and as per the pavement design section of this report. The upper 12 inches of the soil subgrade beneath the pavement section shall be compacted to a minimum compaction of 95% of maximum dry density as determined by test method ASTM D1557. The finished subgrades shall be tested and approved by the Geotechnical Engineer prior to the placement of additional pavement of additional pavement courses. 4. AGGREGATE BASE — The aggregate base shall be spread and compacted on the prepared subgrade in conformity with the lines, grades, and dimensions shown on the plans. The aggregate base should conform to WSDOT Standard Specification for Crushed Surfacing Base Course or Top Course (Item 9-03.9(3)). The base material shall be compacted to a minimum compaction of 95% as determined by ASTM D1557. Each layer of subbase shall be tested and approved by the Geotechnical Engineer prior to the placement of successive layers. 5. ASPHALTIC CONCRETE SURFACING — Asphaltic concrete surfacing shall consist of a mixture of mineral aggregate and paving grade asphalt, mixed at central mixing plant and spread and compacted on a prepared base in conformity with the lines, grades, and dimensions shown on the plans. The drying, proportioning, and mixing of the materials shall conform to WSDOT Specifications. The prime coat, spreading and compacting equipment, and spreading and compacting the mixture shall conform to WSDOT Specifications, with the exception that no surface course shall be placed when the atmospheric temperature is below 50 degrees F. The surfacing shall be rolled with combination steel - wheel and pneumatic rollers, as described in WSDOT Specifications. The surface course shall be placed with an approved self-propelled mechanical spreading and finishing machine. 6. TACK COAT — The tack (mixing type asphaltic emulsion) shall conform to and be applied in accordance with the requirements of WSDOT Specifications. Krazan and Associates, Inc. Offices Serving The Western United States