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24-100902-GeoTech Report-3.13.24EarthSolutionsNWLLC EarthSolutions NW LLC Geotechnical Engineering Construction Observation/Testing Environmental Services 15365 N.E.90th Street,Suite 100 Redmond,WA 98052 (425)449-4704 Fax (425)449-4711 www.earthsolutionsnw.com GEOTECHNICAL ENGINEERING STUDY PROPOSED SINGLE-FAMILY RESIDENCE SOUTHWEST 296 STREET AND 2 PLACE SOUTHWEST FEDERAL WAY,WASHINGTON ES-8670 TH ND PREPARED FOR CHRISTOPHER PENWELL September 1, 2023 _________________________ Chase G. Halsen, L.G., L.E.G. Senior Project Geologist _________________________ Henry T. Wright, P.E. Associate Principal Engineer GEOTECHNICAL ENGINEERING STUDY PROPOSED SINGLE-FAMILY RESIDENCE SOUTHWEST 296TH STREET AND 2ND PLACE SOUTHWEST FEDERAL WAY, WASHINGTON ES-8670 Earth Solutions NW, LLC 15365 Northeast 90th Street, Suite 100 Redmond, Washington 98052 Phone: 425-449-4704 | Fax: 425-449-4711 www.earthsolutionsnw.com 09/01/2023 09/01/2023 Geotechnical-Engineering Report Important Information about This Subsurface problems are a principal cause of construction delays, cost overruns, claims, and disputes. While you cannot eliminate all such risks, you can manage them. The following information is provided to help. The Geoprofessional Business Association (GBA) has prepared this advisory to help you – assumedly a client representative – interpret and apply this geotechnical-engineering report as effectively as possible. In that way, you can benefit from a lowered exposure to problems associated with subsurface conditions at project sites and development of them that, for decades, have been a principal cause of construction delays, cost overruns, claims, and disputes. If you have questions or want more information about any of the issues discussed herein, contact your GBA-member geotechnical engineer. Active engagement in GBA exposes geotechnical engineers to a wide array of risk-confrontation techniques that can be of genuine benefit for everyone involved with a construction project. Understand the Geotechnical-Engineering Services Provided for this Report Geotechnical-engineering services typically include the planning, collection, interpretation, and analysis of exploratory data from widely spaced borings and/or test pits. Field data are combined with results from laboratory tests of soil and rock samples obtained from field exploration (if applicable), observations made during site reconnaissance, and historical information to form one or more models of the expected subsurface conditions beneath the site. Local geology and alterations of the site surface and subsurface by previous and proposed construction are also important considerations. Geotechnical engineers apply their engineering training, experience, and judgment to adapt the requirements of the prospective project to the subsurface model(s). Estimates are made of the subsurface conditions that will likely be exposed during construction as well as the expected performance of foundations and other structures being planned and/or affected by construction activities. The culmination of these geotechnical-engineering services is typically a geotechnical-engineering report providing the data obtained, a discussion of the subsurface model(s), the engineering and geologic engineering assessments and analyses made, and the recommendations developed to satisfy the given requirements of the project. These reports may be titled investigations, explorations, studies, assessments, or evaluations. Regardless of the title used, the geotechnical-engineering report is an engineering interpretation of the subsurface conditions within the context of the project and does not represent a close examination, systematic inquiry, or thorough investigation of all site and subsurface conditions. Geotechnical-Engineering Services are Performed for Specific Purposes, Persons, and Projects, and At Specific Times Geotechnical engineers structure their services to meet the specific needs, goals, and risk management preferences of their clients. A geotechnical-engineering study conducted for a given civil engineer will not likely meet the needs of a civil-works constructor or even a different civil engineer. Because each geotechnical-engineering study is unique, each geotechnical-engineering report is unique, prepared solely for the client. Likewise, geotechnical-engineering services are performed for a specific project and purpose. For example, it is unlikely that a geotechnical- engineering study for a refrigerated warehouse will be the same as one prepared for a parking garage; and a few borings drilled during a preliminary study to evaluate site feasibility will not be adequate to develop geotechnical design recommendations for the project. Do not rely on this report if your geotechnical engineer prepared it: • for a different client; • for a different project or purpose; • for a different site (that may or may not include all or a portion of the original site); or • before important events occurred at the site or adjacent to it; e.g., man-made events like construction or environmental remediation, or natural events like floods, droughts, earthquakes, or groundwater fluctuations. Note, too, the reliability of a geotechnical-engineering report can be affected by the passage of time, because of factors like changed subsurface conditions; new or modified codes, standards, or regulations; or new techniques or tools. If you are the least bit uncertain about the continued reliability of this report, contact your geotechnical engineer before applying the recommendations in it. A minor amount of additional testing or analysis after the passage of time – if any is required at all – could prevent major problems. Read this Report in Full Costly problems have occurred because those relying on a geotechnical- engineering report did not read the report in its entirety. Do not rely on an executive summary. Do not read selective elements only. Read and refer to the report in full. You Need to Inform Your Geotechnical Engineer About Change Your geotechnical engineer considered unique, project-specific factors when developing the scope of study behind this report and developing the confirmation-dependent recommendations the report conveys. Typical changes that could erode the reliability of this report include those that affect: • the site’s size or shape; • the elevation, configuration, location, orientation, function or weight of the proposed structure and the desired performance criteria; • the composition of the design team; or • project ownership. As a general rule, always inform your geotechnical engineer of project or site changes – even minor ones – and request an assessment of their impact. The geotechnical engineer who prepared this report cannot accept responsibility or liability for problems that arise because the geotechnical engineer was not informed about developments the engineer otherwise would have considered. Most of the “Findings” Related in This Report Are Professional Opinions Before construction begins, geotechnical engineers explore a site’s subsurface using various sampling and testing procedures. Geotechnical engineers can observe actual subsurface conditions only at those specific locations where sampling and testing is performed. The data derived from that sampling and testing were reviewed by your geotechnical engineer, who then applied professional judgement to form opinions about subsurface conditions throughout the site. Actual sitewide-subsurface conditions may differ – maybe significantly – from those indicated in this report. Confront that risk by retaining your geotechnical engineer to serve on the design team through project completion to obtain informed guidance quickly, whenever needed. This Report’s Recommendations Are Confirmation-Dependent The recommendations included in this report – including any options or alternatives – are confirmation-dependent. In other words, they are not final, because the geotechnical engineer who developed them relied heavily on judgement and opinion to do so. Your geotechnical engineer can finalize the recommendations only after observing actual subsurface conditions exposed during construction. If through observation your geotechnical engineer confirms that the conditions assumed to exist actually do exist, the recommendations can be relied upon, assuming no other changes have occurred. The geotechnical engineer who prepared this report cannot assume responsibility or liability for confirmation-dependent recommendations if you fail to retain that engineer to perform construction observation. This Report Could Be Misinterpreted Other design professionals’ misinterpretation of geotechnical- engineering reports has resulted in costly problems. Confront that risk by having your geotechnical engineer serve as a continuing member of the design team, to: • confer with other design-team members; • help develop specifications; • review pertinent elements of other design professionals’ plans and specifications; and • be available whenever geotechnical-engineering guidance is needed. You should also confront the risk of constructors misinterpreting this report. Do so by retaining your geotechnical engineer to participate in prebid and preconstruction conferences and to perform construction- phase observations. Give Constructors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can shift unanticipated-subsurface-conditions liability to constructors by limiting the information they provide for bid preparation. To help prevent the costly, contentious problems this practice has caused, include the complete geotechnical-engineering report, along with any attachments or appendices, with your contract documents, but be certain to note conspicuously that you’ve included the material for information purposes only. To avoid misunderstanding, you may also want to note that “informational purposes” means constructors have no right to rely on the interpretations, opinions, conclusions, or recommendations in the report. Be certain that constructors know they may learn about specific project requirements, including options selected from the report, only from the design drawings and specifications. Remind constructors that they may perform their own studies if they want to, and be sure to allow enough time to permit them to do so. Only then might you be in a position to give constructors the information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. Conducting prebid and preconstruction conferences can also be valuable in this respect. Read Responsibility Provisions Closely Some client representatives, design professionals, and constructors do not realize that geotechnical engineering is far less exact than other engineering disciplines. This happens in part because soil and rock on project sites are typically heterogeneous and not manufactured materials with well-defined engineering properties like steel and concrete. That lack of understanding has nurtured unrealistic expectations that have resulted in disappointments, delays, cost overruns, claims, and disputes. To confront that risk, geotechnical engineers commonly include explanatory provisions in their reports. Sometimes labeled “limitations,” many of these provisions indicate where geotechnical engineers’ responsibilities begin and end, to help others recognize their own responsibilities and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly. Geoenvironmental Concerns Are Not Covered The personnel, equipment, and techniques used to perform an environmental study – e.g., a “phase-one” or “phase-two” environmental site assessment – differ significantly from those used to perform a geotechnical-engineering study. For that reason, a geotechnical-engineering report does not usually provide environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated subsurface environmental problems have led to project failures. If you have not obtained your own environmental information about the project site, ask your geotechnical consultant for a recommendation on how to find environmental risk-management guidance. Obtain Professional Assistance to Deal with Moisture Infiltration and Mold While your geotechnical engineer may have addressed groundwater, water infiltration, or similar issues in this report, the engineer’s services were not designed, conducted, or intended to prevent migration of moisture – including water vapor – from the soil through building slabs and walls and into the building interior, where it can cause mold growth and material-performance deficiencies. Accordingly, proper implementation of the geotechnical engineer’s recommendations will not of itself be sufficient to prevent moisture infiltration. Confront the risk of moisture infiltration by including building-envelope or mold specialists on the design team. Geotechnical engineers are not building-envelope or mold specialists. Copyright 2019 by Geoprofessional Business Association (GBA). Duplication, reproduction, or copying of this document, in whole or in part, by any means whatsoever, is strictly prohibited, except with GBA’s specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of GBA, and only for purposes of scholarly research or book review. Only members of GBA may use this document or its wording as a complement to or as an element of a report of any kind. Any other firm, individual, or other entity that so uses this document without being a GBA member could be committing negligent or intentional (fraudulent) misrepresentation. Telephone: 301/565-2733 e-mail: info@geoprofessional.org www.geoprofessional.org September 1, 2023 ES-8670 Christopher Penwell 696 Moss Farms Road Cheshire, Connecticut 06410 Greetings: Earth Solutions NW, LLC (ESNW) is pleased to present this geotechnical report to support the proposed project. Based on the results of our investigation, the construction of a single-family residence is feasible from a geotechnical standpoint. Our study indicates the site is underlain by sequenced coarse- to fine-grained, pre-Olympia glacial deposits. Based on the observed soil and groundwater conditions, visual observations, and results of preliminary slope stability analyses, it is our opinion that the slope which comprises the majority of the site area has a moderate to high landslide potential. As such, the proposed structure will need to be supported on deep foundation elements. A further discussion of our slope stability analyses, foundation support recommendations, and considerations are provided in this report. From a geotechnical standpoint, infiltration should not be pursued for the project. The site is located on a fairly steep hillside and the introduction of additional water (via infiltration) could potentially reduce stability of the slope. Furthermore, the observed presence of various groundwater seepage zones, particularly during the summer months, indicates unfavorable site infiltration characteristics. Pertinent geotechnical recommendations are provided in this study. We appreciate the opportunity to be of service to you on this project. If you have any questions regarding the content of this geotechnical engineering study, please call. Sincerely, EARTH SOLUTIONS NW, LLC Chase G. Halsen, L.G., L.E.G. Senior Project Geologist cc: Barghausen Consulting Engineers, Inc. Attention: Ivana Halvorsen Vicente Varas, P.E. 15365 N.E. 90th Street, Suite 100 • Redmond, WA 98052 •(425) 449-4704 • FAX (425) 449-4711 Earth Solutions NW LLC Geotechnical Engineering, Construction Observation/Testing and Environmental Services Earth Solutions NW, LLC Table of Contents ES-8670 PAGE INTRODUCTION ................................................................................. 1 General .................................................................................... 1 Project Description ................................................................. 1 SITE CONDITIONS ............................................................................. 2 Surface ..................................................................................... 2 Subsurface .............................................................................. 2 Topsoil .......................................................................... 2 Fill .................................................................................. 2 Native Soil and Geologic Setting ................................ 3 Groundwater ................................................................. 3 Geologically Hazardous Areas .............................................. 3 Landslide Hazard Areas ............................................... 4 Deep Foundation Support ................................... 4 Erosion Hazard ............................................................. 5 DISCUSSION AND RECOMMENDATIONS ....................................... 5 General .................................................................................... 5 Site Preparation and Earthwork ............................................. 5 Temporary Erosion Control ......................................... 5 Stripping ....................................................................... 6 Excavations and Slopes .............................................. 6 In-situ and Imported Soil ............................................. 7 Structural Fill ................................................................ 7 Site Modifications ......................................................... 7 Foundations ............................................................................ 8 Axial Load Capacity and Pipe Pile Installation ........... 8 Lateral Load Capacity ................................................... 8 Seismic Design ....................................................................... 9 Slab-on-Grade Floors ............................................................. 9 Retaining Walls ....................................................................... 10 Drainage................................................................................... 10 Infiltration Feasibility ................................................... 11 Utility Support and Trench Backfill ....................................... 11 LIMITATIONS ...................................................................................... 11 Additional Services ................................................................. 11 REFERENCES .................................................................................... 12 Earth Solutions NW, LLC Table of Contents Cont’d ES-8670 GRAPHICS Plate 1 Vicinity Map Plate 2 Subsurface Exploration Plan Plate 3 Retaining Wall Drainage Detail Plate 4 Footing Drain Detail APPENDICES Appendix A Subsurface Exploration Logs Appendix B Laboratory Test Results Appendix C Slope/W Output Earth Solutions NW, LLC GEOTECHNICAL ENGINEERING STUDY PROPOSED SINGLE-FAMILY RESIDENCE SOUTHWEST 296TH STREET AND 2ND PLACE SOUTHWEST FEDERAL WAY, WASHINGTON ES-8670 INTRODUCTION General This geotechnical engineering study was prepared for the proposed single-family residence to be constructed near the intersection of Southwest 296th Street and 2nd Place Southwest, in Federal Way, Washington. This study was prepared to provide geotechnical recommendations for currently proposed development plans and included the following geotechnical services:  Test pit and boring explorations to characterize soil and groundwater conditions.  Laboratory testing of representative soil samples collected at the test locations.  Geotechnical engineering analyses. Project Description The proposed project is currently pursuing the construction of a single-family residence and associated infrastructure improvements, which will be targeted at the southwest corner of the site area. To our understanding, this location was chosen due to various site constraints relating to identified critical areas and the associated buffers. We understand that stormwater runoff will likely be managed via a detention structure to be located adjacent to the access driveway. We understand that the proposed residential structure will be three stories and constructed using relatively lightly loaded wood framing. Perimeter footing loads will likely be about 2 to 3 kips per linear foot. Slab-on-grade loading is anticipated to be approximately 150 pounds per square foot (psf). We anticipate a series of bench cuts will be utilized across the building envelope to minimize disturbances to the existing slope. If the above design assumptions either change or are incorrect, ESNW should be contacted to review the recommendations provided in this report. ESNW should review the final designs to confirm that appropriate geotechnical recommendations have been incorporated into the plans. Christopher Penwell ES-8670 September 1, 2023 Page 2 Earth Solutions NW, LLC SITE CONDITIONS Surface The subject site is located near the Southwest 296th Street and 2nd Place Southwest intersection in Federal Way, Washington. The approximate site location is depicted on Plate 1 (Vicinity Map) and consists of King County parcel number 119600-3800, totaling a gross site area of about 0.94 acres. The site is undeveloped and heavily forested. The only exception is a local access road along the eastern and southern property edge that provides access to the adjacent residence. Topography generally descends to the northeast towards a drainage features that trends in a northwest-to-southeast fashion. Limited topography descends to the southwest on the opposite side of this feature. In total, about 75 to 80 feet of elevation change occurs across the site. The referenced site plan packet indicates that the majority of site slopes possess a gradient of less than 40 percent. However, gradients over 40 percent are present within the west-central site area and other isolated pockets across the property. Subsurface An ESNW representative observed, logged, and sampled the excavation of one test pit on July 15, 2022, and two soil borings on July 19, 2022. The test pit was extended to a depth of about 9.5 feet below the ground surface (bgs) while the borings were advanced to depths of about 31.5 and 51 feet bgs. All subsurface explorations were completed with exploratory equipment and operators retained by ESNW. The approximate locations of the explorations are depicted on Plate 2 (Subsurface Exploration Plan). Please refer to the soil logs provided in Appendix A for a more detailed description of the encountered subsurface conditions. Representative soil samples collected at the exploration locations were analyzed following Unified Soil Classification System (USCS) and United States Department of Agriculture (USDA) methods and procedures. Topsoil Topsoil was encountered in approximately the upper six inches of existing grades at the test pit location. The topsoil was characterized by a dark brown color, the presence of fine organic material, and small root intrusions. Based on our observations, a similar topsoil condition can be expected across the building envelope. Fill Existing fill was not interpreted at the boring locations, but rather, the notation of fill in the attached soil logs represents material placed to establish a level drilling pad. These pads were constructed at the time of our test pit exploration. Christopher Penwell ES-8670 September 1, 2023 Page 3 Earth Solutions NW, LLC Native Soil and Geologic Setting Native soils were classified primarily as layered silty sand and silt with variable sand percentages (USCS: SM and ML, respectively). In general, soils within the upper approximate 10 to 15 feet of existing grades were characterized as being loose to medium dense. Thereafter (at the boring locations), native soils were encountered in a dense to very dense condition and extended to the terminus of each boring location, which occurred at depths between about 31.5 and 51.0 feet bgs. Medium dense soils were encountered at the terminus of the test pit location which occurred at a depth of about nine-and-one-half feet bgs. At the time of the July 2022 exploration, native soils were observed in a moist to wet condition. The referenced geologic map indicates that the site is underlain by pre-Olympia age course- grained deposits (Qpogc). Surface exposures of pre-Olympia age fine-grained deposits are mapped directly downgradient of the site. The referenced Web Soil Survey indicates the site area is primarily underlain by Indianola loamy sand and Alderwood Kitsap soils (Map Unit Symbols: InD and AkF, respectively). The Indianola series is derived from sandy glacial outwash while the Alderwood/Kitsap soils are derived from basal till. Based on the conditions encountered during the subsurface exploration, native soils are generally considered representative of sequenced course- to fine-grained deposits that are pre-Olympia in age. For stormwater runoff design characterizations, the native site soil may be considered at Type C soil. Groundwater Perched groundwater seepage was encountered at both boring locations during the July 2022 fieldwork. In general, the seepage was first exposed at a depth of about seven-and-one-half to eight-and-one-half feet bgs, extending to the termination depth of each location, and characterized with variable degrees of flow rate. Perched groundwater was not encountered within the test pit location. Groundwater seeps are common within glacial deposits, and the elevations and/or flow volumes of seepages can fluctuate depending on many factors, including precipitation duration and intensity, the time of year, and soil conditions. In general, groundwater elevations are higher during the winter, spring, and early summer months. Geologically Hazardous Areas The Federal Way Revised Code (FWRC) 19.145.220 recognizes and defines geologically hazardous areas as landslide, erosion, and seismic hazards. Based on our review of the FWRC definitions (19.05.070), the site is considered to possess a landslide and erosion hazard due to the current slope gradients and identified soil units within the site area. A discussion of the identified hazard areas and applicable mitigation recommendations are provided in the following sections. Please note that it is our opinion that any seismic-related instability coincides with any potential site landslide hazard. As such, a specific seismic hazard discussion is not provided. Christopher Penwell ES-8670 September 1, 2023 Page 4 Earth Solutions NW, LLC Landslide Hazard Areas Based on a review of the critical areas impact plan sheet, the majority of site gradients are between 15 percent and 39.99 percent. However, slope areas of 40 percent gradient or more over at least a 10-foot elevation chare are present within the west-central site area and extend into the proposed footprint of the residence. As such, these sloping areas may be considered a potential landslide hazard per the FWRC definitions. The standard buffer associated with landslide hazard areas is 50 feet per the FWRC. However, we understand that a reduced buffer and/or development within a landslide hazard area may be considered provided it will not lead to or create any increased landslide hazard or be at risk of landslide hazard damages. To further evaluate the potential landslide hazard, a slope stability analysis was performed for the subject site to represent the current (pre-construction) and post-construction site configuration. Please note that general assumptions about the foundation excavation configuration were made in the development of the stability analyses. Two models were produced for each condition; one represented slope performance under static site conditions while the other represented slope performance under seismic conditions. Soil strength parameters were chosen based on our experience with similar deposits and the WSDOT Geotechnical manual. A seismic coefficient (Kh) of 0.343 was used in the model. The following table depicts the minimum factor- of-safety associated with each condition and model: Pre-Existing Condition FOS Post-Construction Condition FOS Static 1.63 Static 1.58 Seismic 1.00 Seismic 1.08 Based on the modeling, slope stability is interpreted to be stable under static conditions and are generally unchanged between the two conditions. However, the seismic analysis results in safety factors that are below acceptable standards. Due to lower than acceptable slope stability safety factors, it is our opinion that the residence will need to be supported on deep foundation elements. Deep Foundation Support In our opinion, the proposed foundation can be supported on a pipe pile system in which each pile is driven into the dense to very dense native soils at depth. Although some lateral resistance can be derived from the pipe pile system, the implementation is not considered to be landslide hazard mitigation and was not modeled as such in our slope stability analyses. The deep foundation elements would provide continued foundation support should soil movement occur and result in the loss of soil beneath or adjacent to footing elements. It must be noted that this approach would not mitigate the potential for soil movement, and as such, the residence may not be habitable if a landslide occurs. It is our opinion that this approach will not decrease slope stability characteristics or increase the potential for impacts to neighboring properties. Foundation design recommendations and pipe pile considerations are provided in this report. Christopher Penwell ES-8670 September 1, 2023 Page 5 Earth Solutions NW, LLC Erosion Hazard Per the FWRC 19.145.240, there is no standard buffer associated with erosion hazard areas. However, the project should follow the recommendations of the critical area report to minimize the adverse effects of the potential hazard on the proposed project. In our opinion, erosion can be successfully managed and mitigated both during and post-construction provided typical site BMPs are utilized and managed and permanent landscaping is installed following the completion of the project. DISCUSSION AND RECOMMENDATIONS General Based on the results of our investigation, the construction of the proposed single-family residence is feasible from a geotechnical standpoint. The primary geotechnical considerations for the proposed development concern temporary excavation support, foundation support recommendations, geologically hazardous area mitigation, and stormwater management design. Site Preparation and Earthwork Initial site preparation activities will consist of installing temporary erosion control measures, establishing grading limits, and site clearing and stripping activities. Subsequent earthwork activities will involve excavation for the building, building pad preparation, and installation of infrastructure and stormwater management improvements. Temporary Erosion Control The following temporary erosion and sediment control Best Management Practices (TESC BMPs) are offered:  Temporary construction entrances and drive lanes should be constructed with at least six inches of quarry spalls to both minimize off-site soil tracking and provide a stable access entrance surface. A woven geotextile fabric can be placed beneath the quarry spalls to provide greater stability if needed.  Silt fencing should be placed around the site perimeter.  When not in use, soil stockpiles should be covered or otherwise protected. Stockpiles should not be placed on or directly adjacent to slopes.  Temporary measures for controlling surface water runoff, such as interceptor trenches, sumps, or interceptor swales, should be installed before beginning earthwork activities.  Based on limited site space and sloped topography, a stormwater collection tank may be necessary. Christopher Penwell ES-8670 September 1, 2023 Page 6 Earth Solutions NW, LLC  Dry soils disturbed during construction should be wetted to reduce dust.  When appropriate, permanent planting or hydroseeding will help to stabilize site soils.  Based on the site soils and sloped topography, we recommend completing earthwork during the dry season. Additional TESC BMPs, as specified by the project civil engineer on the plans, should be incorporated into construction activities. TESC measures will require upkeep and potential modification during construction to ensure proper function; such upkeep should be coordinated with the site erosion control lead, where applicable. Stripping Topsoil was generally encountered in the upper approximately six inches of existing grades at the test pit location. For stripping estimations, an average topsoil thickness of about six inches can be assumed, based on our field observations. Where encountered, organic-rich topsoil should be stripped and segregated into a stockpile for later use on site or to be exported. Excavations and Slopes Based on the soil conditions observed at the test pit locations, the following allowable temporary slope inclinations, as a function of horizontal to vertical (H:V) inclination, may be used. The applicable Federal Occupation Safety and Health Administration (OSHA) and Washington Industrial Safety and Health Act (WISHA) soil classifications are also provided:  Loose to medium dense soil 1.5H:1V (Type C)  Areas exposing groundwater seepage 1.5H:1V (Type C)  Dense to very dense, undisturbed native soil 0.75H:1V (Type A) Steeper temporary slope inclinations within undisturbed, very dense native soil may be feasible based on the soil and groundwater conditions exposed within the excavations. ESNW can evaluate the feasibility of utilizing steeper temporary slopes on a case-by-case basis at the time of construction. In any case, an ESNW representative should observe temporary slopes to confirm inclinations are suitable for the exposed soil conditions and to provide additional excavation and slope stability recommendations, as necessary. If the recommended temporary slope inclinations cannot be achieved, temporary shoring may be necessary to support excavations. Permanent slopes should be graded to 2H:1V (or flatter) and planted with vegetation to enhance stability and minimize erosion potential. Permanent slopes should be observed by ESNW before vegetation and landscaping. ESNW must review the proposed grading plans to assist in evaluating suitable temporary slope inclinations and/or the necessity of temporary shoring designs. Christopher Penwell ES-8670 September 1, 2023 Page 7 Earth Solutions NW, LLC In-situ and Imported Soil Successful use of the on-site soil as structural fill will largely be dictated by the moisture content at the time of placement and compaction. Based on the conditions observed during the subsurface exploration, the native soils are considered to possess a moderate to high moisture sensitivity. Depending on the time of year construction occurs, remedial measures (such as soil aeration) may be necessary as part of site grading and earthwork activities. If the on-site soil cannot be successfully compacted, the use of imported soil may be necessary. In our opinion, a contingency should be provided in the project budget for the export of soil that cannot be successfully compacted as structural fill, particularly if grading activities take place during periods of extended rainfall activity. In general, soils with fine contents greater than 5 percent typically degrade rapidly when exposed to periods of rainfall. Imported structural fill soil should consist of well-graded, granular soil that can achieve a suitable working moisture content. During wet weather conditions, imported soil intended for use as structural fill should consist of a well-graded, granular soil with a fines content of 5 percent or less (where the fines content is defined as the percent passing the Number 200 sieve, based on the minus three-quarter-inch fraction). Structural Fill Structural fill is defined as compacted soil placed in foundation, slab-on-grade, roadway, permanent slope, retaining wall, and utility trench backfill areas. The following recommendations are provided for soils intended for use as structural fill:  Moisture content At or slightly above optimum  Relative compaction (minimum) 95 percent (per ASTM D1557)  Loose lift thickness (maximum) 12 inches Existing site soil may only be considered suitable for use as structural fill if a suitable moisture content is achieved at the time of placement and compaction. If the on-site soil cannot achieve the above specifications, the use of imported structural fill material will likely be necessary. Concerning underground utility installations and backfill, local jurisdictions will likely dictate soil type(s) and compaction requirements. Site Modifications From a geotechnical standpoint, the project should strive to minimize the amount of proposed grade fills, to the extent possible. ESNW should review grading plans to evaluate any potential impacts resulting from the placement and compaction of fill material. Christopher Penwell ES-8670 September 1, 2023 Page 8 Earth Solutions NW, LLC Foundations As discussed in the Geologically Hazardous Areas section of this report, it is our opinion that the proposed residence be supported on deep foundation elements in attempt to provide continued foundation support should a landslide occur. Design recommendations relating to pile capacities is provided in this section. From a geotechnical standpoint, 4-inch diameter pipe piles (or larger) should be considered for this project. Based on the conditions encountered during our subsurface explorations, we anticipate dense to very dense native soils to be encountered at depths of about 20 to 30 feet bgs; however, ultimate pipe pile lengths will be dictated by achieving adequate refusal in dense soil. In our opinion, the contractor should consider ultimate pile lengths in excess of about 30 feet. Due to the encountered groundwater conditions and overall soil characteristics, the pipe piles should consist of galvanized steel to reduce the potential for corrosion. Axial Load Capacity and Pipe Pile Installation Provided the pipe piles are driven to refusal, the following allowable axial load capacities may be used for the design: Pile Diameter (in.) Load Capacity (kips) Refusal Criteria (seconds/inch) Minimum Hammer Size (lb.) 4 20 16 850 With structural loading as expected, total settlement in the range of one inch and differential settlement of about one-half inch is anticipated. Most settlement should occur during construction, as dead loads are applied. If modified installation methods or equipment are used during construction, ESNW should be notified to review the recommendations provided in this report. Typically, piles are alternatively driven with respect to other piles in a row to minimize the temporary loss of soil strength during installation (which may affect subsequent pile installations). An ESNW representative should observe the pipe pile installations to verify the achievement of adequate refusal. In addition, we recommend a pipe pile load testing program be incorporated into the final plans. Load testing on at least 3 percent of the installed piles should be completed. The testing program would ideally also include one or two verification tests on the driven pipe piles to 200 percent of the design load. Lateral Load Capacity The lateral load capacity of pipe piles is minimal and should be neglected for design purposes. If lateral load capacity is required, ESNW can review the pile design and provide batter pile recommendations. Limited lateral load capacity can be provided by the passive resistance developed by grade beams, if applicable. Christopher Penwell ES-8670 September 1, 2023 Page 9 Earth Solutions NW, LLC Seismic Design The 2018 International Building Code (2018 IBC) recognizes the most recent edition of the Minimum Design Loads for Buildings and Other Structures manual (ASCE 7-16) for seismic design, specifically concerning earthquake loads. Based on the soil conditions encountered at the test locations, the parameters and values provided below are recommended for seismic design per the 2018 IBC. Parameter Value Site Class C* Mapped short-period spectral response acceleration, SS (g) 1.352 Mapped 1-second period spectral response acceleration, S1 (g) 0.464 Short period site coefficient, Fa 1.2 Long-period site coefficient, Fv 1.5 Adjusted short-period spectral response acceleration, SMS (g) 1.623 Adjusted 1-second period spectral response acceleration, SM1 (g) 0.697 Design short-period spectral response acceleration, SDS (g) 1.082 Design 1-second period spectral response acceleration, SD1 (g) 0.464 * Assumes very dense soil conditions, encountered to a maximum depth of 51 feet bgs during the July 2022 field exploration, remain very dense to at least 100 feet bgs. Slab-on-Grade Floors Slab-on-grade floors for the proposed residential structures should be supported by competent, firm, and unyielding subgrades. Unstable or yielding subgrade areas should be recompacted or overexcavated and replaced with suitable structural fill before slab construction. A capillary break consisting of at least four inches of free-draining crushed rock or gravel should be placed below each slab. The free-draining material should have a fines content of 5 percent or less (where the fines content is defined as the percent passing the Number 200 sieve, based on the minus three- quarter-inch fraction). In areas where slab moisture is undesirable, the installation of a vapor barrier below the slab should be considered. Vapor barriers should be made from material specifically designed for use as a vapor barrier and should be installed by the manufacturer’s recommendations. Christopher Penwell ES-8670 September 1, 2023 Page 10 Earth Solutions NW, LLC Retaining Walls Retaining walls must be designed to resist earth pressures and applicable surcharge loads. The following parameters may be used for the design:  Active earth pressure (unrestrained condition) 35 pcf (equivalent fluid)  Active earth pressure (backslope) 55 pcf  At-rest earth pressure (restrained condition) 55 pcf  At-rest earth pressure (backslope) 75 pcf  Traffic surcharge* (passenger vehicles) 70 psf (rectangular distribution)  Passive earth pressure 300 pcf (equivalent fluid)  Coefficient of friction 0.40  Seismic surcharge 8H psf** * Where applicable. ** Where H equals the retained height (in feet). The above passive earth pressure and coefficient of friction values include a FOS of 1.5 and are based on a level backfill condition and level grade at the wall toe. Revised design values will be necessary if sloping grades are to be used above or below retaining walls. Additional surcharge loading from adjacent foundations, sloped backfill, or other relevant loads should be included in the retaining wall design. Retaining walls should be backfilled with free-draining material that extends along with the height of the wall and a distance of at least 18 inches behind the wall. The upper 12 inches of the wall backfill may consist of less permeable soil if desired. A sheet drain may be considered instead of using free-draining backfill. A perforated drainpipe should be placed along the base of the wall and connected to an approved discharge location. A typical retaining wall drainage detail is provided on Plate 3. If drainage is not provided, hydrostatic pressures should be included in the wall design. Drainage Zones of perched groundwater seepage could develop in site excavations depending on the time of year grading operations take place, particularly within deeper excavations. Temporary measures to control surface water runoff and groundwater during construction would likely involve interceptor trenches, interceptor swales, and sumps; however, stormwater collection tanks may also be necessary. ESNW should be consulted during preliminary grading to both identify areas of seepage and provide recommendations to reduce the potential for seepage-related instability. Christopher Penwell ES-8670 September 1, 2023 Page 11 Earth Solutions NW, LLC Finish grades must be designed to direct surface drain water away from structures and slopes where feasible. Water must not be allowed to pond adjacent to structures or slopes. In our opinion, foundation drains should be installed along building perimeter footings. A typical foundation drain detail is provided on Plate 4. Infiltration Feasibility From a geotechnical standpoint, infiltration should not be pursued for the project. The site is located on a steep hillside and the introduction of additional water (via infiltration, perforated stub outs, etc.) could potentially reduce slope stability and increase erosion. Furthermore, the observed presence of various groundwater seepage zones, particularly during the summer months, indicates unfavorable site infiltration characteristics. Utility Support and Trench Backfill In our opinion, the native soil will generally be suitable for the support of utilities. Remedial measures may be necessary for some areas to provide support for utilities, such as overexcavation and replacement with structural fill and/or placement of geotextile fabric. Groundwater seepage may be encountered within utility excavations, and caving of trench walls may occur where groundwater is encountered. Depending on the time of year and conditions encountered, dewatering or temporary trench shoring may be necessary during utility excavation and installation. The on-site soil is not considered suitable for use as structural backfill throughout the utility trench excavations unless the soil is at (or slightly above) the optimum moisture content at the time of placement and compaction. Moisture conditioning of the soil may be necessary at some locations before use as structural fill. Each section of the utility lines must be adequately supported by the bedding material. Utility trench backfill should be placed and compacted to the structural fill specifications previously detailed in this report or to the applicable specifications of the presiding jurisdiction. LIMITATIONS This study has been prepared for the exclusive use of Christopher Penwell and his representatives. The recommendations and conclusions provided in this study are professional opinions consistent with the level of care and skill that is typical of other members in the profession currently practicing under similar conditions in this area. No warranty, express or implied, is made. Variations in the soil and groundwater conditions observed at the test locations may exist and may not become evident until construction. ESNW should reevaluate the conclusions provided in this study if variations are encountered. Additional Services ESNW should have an opportunity to review the final project plans concerning the geotechnical recommendations provided in this report. ESNW should also be retained to provide testing and consultation services during construction. Christopher Penwell ES-8670 September 1, 2023 Page 12 Earth Solutions NW, LLC REFERENCES  WSS, maintained by the Natural Resources Conservation Service under the USDA  Lidar-Revised Geologic Map of the Poverty Bay 7.5’ Quadrangle, King and Pierce Counties, Washington, prepared by R.W. Tabor, D.B. Booth, and K.G. Troost, 2014  Penwell Property Plan Set, prepared by Barghausen Consulting Engineers, Inc., dated August 3, 2023. Geotechnical Engineering,Construction Observation/Testing and Environmental Services Drwn.MRS Checked CGH Date Aug.2022 Date 08/09/2022 Proj.No.8670 Plate 1 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Vicinity Map Redondo Bay Lot 35 Federal Way,Washington Reference: King County,Washington OpenStreetMap.org NORTH NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. SITE Federal Way Plate Proj.No. Date Checked DrawnEarthSolutionsNWLLC GeotechnicalEngineering,ConstructionObservation/TestingandEnvironmentalServicesEarthSolutionsNWLLCEarthSolutionsNWLLCMRS NORTH NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. NOTE:The graphics shown on this plate are not intended for design purposes or precise scale measurements,but only to illustrate the approximate test locations relative to the approximate locations of existing and /or proposed site features.The information illustrated is largely based on data provided by the client at the time of our study.ESNW cannot be responsible for subsequent design changes or interpretation of the data by others. LEGEND Approximate Location of ESNW Boring,Proj.No. ES-8670,July 2022 Approximate Location of ESNW Test Pit,Proj.No. ES-8670,July 2022 Subject Site Cross Section 0 4 0 8 0 1 6 0 Sc ale in Feet1"=8 0 ' CGH 08/31/2023 8670 2SubsurfaceExplorationPlan RedondoBayLot35FederalWay,WashingtonTP-1 B-1 TP-1 B-1 B-2 S.W.296TH STREET 2ND PLACE S.W.200 190 180 170 160 150 140 200 190 180 170 160 150140 Geotechnical Engineering,Construction Observation/Testing and Environmental Services Drawn CAM Checked HTW Date May 2023 Date 05/08/2023 Proj.No.8670 Plate 3 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC NOTES: Free-draining Backfill should consist of soil having less than 5 percent fines. Percent passing No.4 sieve should be 25 to 75 percent. Sheet Drain may be feasible in lieu of Free-draining Backfill,per ESNW recommendations. Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1-inch Drain Rock. LEGEND: Free-draining Structural Backfill 1-inch Drain Rock 18"Min. Structural Fill Perforated Rigid Drain Pipe (Surround in Drain Rock) SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAW ING Retaining Wall Drainage Detail Redondo Bay Lot 35 Federal Way,Washington Geotechnical Engineering,Construction Observation/Testing and Environmental Services Drawn CAM Checked HTW Date May 2023 Date 05/08/2023 Proj.No.8670 Plate 4 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Slope Perforated Rigid Drain Pipe (Surround in Drain Rock) 18"Min. NOTES: Do NOT tie roof downspouts to Footing Drain. Surface Seal to consist of 12"of less permeable,suitable soil.Slope away from building. LEGEND: Surface Seal:native soil or other low-permeability material. 1-inch Drain Rock SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAW ING Footing Drain Detail Redondo Bay Lot 35 Federal Way,Washington Earth Solutions NW, LLC Appendix A Subsurface Exploration Logs ES-8670 Subsurface conditions at the subject site were explored on July 15, 2022, and July 19, 2022, where one test pit was excavated and two soil borings were advanced. The machinery and operators used to perform each exploration were retained by ESNW. The approximate locations of the explorations are illustrated on Plate 2 of this study. The exploration logs are provided in this Appendix. The test pit was excavated to a maximum depth of approximately 9.5 feet bgs while the borings were advanced to 31.5 and 51.0 feet bgs. The final logs represent the interpretations of the field logs and the results of laboratory analyses. The stratification lines on the logs represent the approximate boundaries between soil types. In actuality, the transitions may be more gradual. >12%Fines<5%FinesHighlyOrganicSoilsSiltsandClaysLiquidLimit50orMoreSiltsandClaysLiquidLimitLessThan50Fine-GrainedSoils-50%orMorePassesNo.200SieveCoarse-GrainedSoils-MoreThan50%RetainedonNo.200SieveSands-50%orMoreofCoarseFractionPassesNo.4SieveGravels-MoreThan50%ofCoarseFractionRetainedonNo.4Sieve>12%Fines<5%FinesGW GP GM GC SW SP SM SC ML CL OL MH CH OH PT Well-graded gravel with or without sand,little to no fines Poorly graded gravel with or without sand,little to no fines Silty gravel with or without sand Clayey gravel with or without sand Well-graded sand with or without gravel,little to no fines Poorly graded sand with or without gravel,little to no fines Silty sand with or without gravel Clayey sand with or without gravel Silt with or without sand or gravel;sandy or gravelly silt Clay of low to medium plasticity;lean clay with or without sand or gravel; sandy or gravelly lean clay Organic clay or silt of low plasticity Elastic silt with or without sand or gravel;sandy or gravelly elastic silt Clay of high plasticity; fat clay with or without sand or gravel;sandy or gravelly fat clay Organic clay or silt of medium to high plasticity Peat,muck,and other highly organic soils EEaarrtthh SSoolluuttiioonnss NNWW LLC Geotechnical Engineering,Construction Observation/Testing and Environmental Services EXPLORATION LOG KEYFillFILLMadeGround Classifications of soils in this geotechnical report and as shown on the exploration logs are based on visual field and/or laboratory observations,which include density/consistency,moisture condition,grain size,and plasticity estimates,and should not be construed to imply field or laboratory testing unless presented herein. Visual-manual and/or laboratory classification methods of ASTM D2487 and D2488 were used as an identification guide for the Unified Soil Classification System. Terms Describing Relative Density and Consistency Coarse-Grained Soils: Fine-Grained Soils: SPT blows/foot SPT blows/foot Test Symbols &Units Fines =Fines Content (%) MC =Moisture Content (%) DD =Dry Density (pcf) Str =Shear Strength (tsf) PID =Photoionization Detector (ppm) OC =Organic Content (%) CEC =Cation Exchange Capacity (meq/100 g) LL =Liquid Limit (%) PL =Plastic Limit (%) PI =Plasticity Index (%) Component Definitions Descriptive Term Size Range and Sieve Number Smaller than No.200 (0.075 mm) Boulders Modifier Definitions Percentage by Weight (Approx.) <5 5 to 14 15 to 29 >30_ Modifier Trace (sand,silt,clay,gravel) Slightly (sandy,silty,clayey,gravelly) Sandy,silty,clayey,gravelly Very (sandy,silty,clayey,gravelly) Moisture Content Dry -Absence of moisture,dusty,dry to the touch Damp -Perceptible moisture,likely below optimum MC Moist -Damp but no visible water,likely at/near optimum MC Wet -Water visible but not free draining, likely above optimum MC Saturated/Water Bearing -Visible free water,typically below groundwater table Symbols Cement grout surface seal Bentonite chips Grout seal Filter pack with blank casing section Screened casing or Hydrotip with filter pack End cap ATD =At time of drilling Static water level (date) _>50 Density Very Loose Loose Medium Dense Dense Very Dense Consistency Very Soft Soft Medium Stiff Stiff Very Stiff Hard <4 4 to 9 10 to 29 30 to 49 <2 2 to 3 4 to 7 8 to 14 15 to 29 _>30 LLC EarthSolutions NW LLC Cobbles Gravel Coarse Gravel Fine Gravel Sand Coarse Sand Medium Sand Fine Sand Silt and Clay Larger than 12" 3"to 12" 3"to No.4 (4.75 mm) 3"to 3/4" 3/4"to No.4 (4.75 mm) No.4 (4.75 mm)to No.200 (0.075 mm) No.4 (4.75 mm)to No.10 (2.00 mm) No.10 (2.00 mm)to No.40 (0.425 mm) No.40 (0.425 mm)to No.200 (0.075 mm) 187.5 184.5 176.0 SS SS SS SS 67 100 100 100 14-10-11 (21) 8-11-13 (24) 6-8-11 (19) 9-14-20 (34) MC = 18.6 Fines = 26.5 MC = 31.8 MC = 30.4 Fines = 99.1 MC = 30.5 SP- SM SM ML SM Brown poorly graded SAND with silt, medium dense, moist (Drill Pad Fill) Gray silty SAND, medium dense, moist to wet -moderate iron oxide staining, [USDA Classification: slightly gravelly sandy LOAM] Brown sandy SILT, medium dense, wet -increased texture, gray layers -trace wood debris -becomes silt [USDA Classification: LOAM] -moderate iron oxide staining layers (1") -light perched groundwater seepage -becomes dense -layered moderate iron oxide staining (<1") Gray silty SAND, very dense, wet 2.5 5.5 14.0 (Continued Next Page)SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 10.0 12.5 15.0 PAGE 1 OF 4 BORING NUMBER B-1 CHECKED BY HTW NOTES SURFACE CONDITIONS Brush AT TIME OF DRILLINGAT TIME OF DRILLING AFTER DRILLING DRILLING CONTRACTOR Geologic Drill Partners DATE STARTED 7/19/22 COMPLETED 7/19/22 GROUND WATER LEVEL: GROUND ELEVATION 190 ft LOGGED BY CGH LATITUDE 47.33696 LONGITUDE -122.33791 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 RECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG 161.0 SS SS SS 100 67 100 13-28-31 (59) 21-34-40 (74) 20-30-44 (74) MC = 29.5 MC = 14.0 Fines = 12.4 MC = 27.8 SM ML Gray silty SAND, very dense, wet (continued) -heavy iron oxide staining, light perched groundwater seepage [USDA Classification: slightly gravelly SAND] -heavy iron oxide staining -moderate to heavy perched groundwater seepage Gray SILT with sand, very dense, wet 29.0 (Continued Next Page)SAMPLE TYPENUMBERDEPTH(ft)15.0 17.5 20.0 22.5 25.0 27.5 30.0 PAGE 2 OF 4 BORING NUMBER B-1 CHECKED BY HTW NOTES SURFACE CONDITIONS Brush AT TIME OF DRILLINGAT TIME OF DRILLING AFTER DRILLING DRILLING CONTRACTOR Geologic Drill Partners DATE STARTED 7/19/22 COMPLETED 7/19/22 GROUND WATER LEVEL: GROUND ELEVATION 190 ft LOGGED BY CGH LATITUDE 47.33696 LONGITUDE -122.33791 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 RECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG 150.0 SS SS SS 100 71 100 23-50/6" 27-34- 50/5" 27-34- 50/5" MC = 25.6 Fines = 83.7 MC = 28.9 MC = 28.9 ML SM Gray SILT with sand, very dense, wet (continued) -heavy perched groundwater seepage [USDA Classification: LOAM] -heavy iron oxide staining -sand lens (unknown thickness) -heavy perched groundwater seepage Gray silty SAND, very dense, wet -sand lens at top 5' of sample -moderately cemented, perched groundwater seepage 40.0 (Continued Next Page)SAMPLE TYPENUMBERDEPTH(ft)30.0 32.5 35.0 37.5 40.0 42.5 45.0 PAGE 3 OF 4 BORING NUMBER B-1 CHECKED BY HTW NOTES SURFACE CONDITIONS Brush AT TIME OF DRILLINGAT TIME OF DRILLING AFTER DRILLING DRILLING CONTRACTOR Geologic Drill Partners DATE STARTED 7/19/22 COMPLETED 7/19/22 GROUND WATER LEVEL: GROUND ELEVATION 190 ft LOGGED BY CGH LATITUDE 47.33696 LONGITUDE -122.33791 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 RECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG 141.0 139.0 SS SS 100 100 27-33- 50/6" 28-50/6" MC = 27.2 MC = 27.3 Fines = 94.7 SM ML Gray silty SAND, very dense, wet (continued) -heavy perched groundwater seepage Gray SILT, very dense, wet -sands lens (unknown thickness) -heavy perched groundwater seepage [USDA Classification: LOAM] Boring terminated at 51. feet become below existing grade. Groundwater seepage encountered at 8.5 to BOH during drilling. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. 49.0 51.0SAMPLE TYPENUMBERDEPTH(ft)45.0 47.5 50.0 PAGE 4 OF 4 BORING NUMBER B-1 CHECKED BY HTW NOTES SURFACE CONDITIONS Brush AT TIME OF DRILLINGAT TIME OF DRILLING AFTER DRILLING DRILLING CONTRACTOR Geologic Drill Partners DATE STARTED 7/19/22 COMPLETED 7/19/22 GROUND WATER LEVEL: GROUND ELEVATION 190 ft LOGGED BY CGH LATITUDE 47.33696 LONGITUDE -122.33791 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 RECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG 166.0 155.0 SS SS SS SS 17 100 100 100 8-4-2 (6) 1-1-5 (6) 6-7-11 (18) 9-11-15 (26) MC = 23.8 MC = 21.8 Fines = 29.1 MC = 28.1 MC = 25.9 Fines = 12.3 SM SM Brown silty SAND, loose, moist to wet (Drill Pad Fill) Gray silty SAND, loose, wet [USDA Classification: slightly gravelly sandy LOAM] -becomes medium dense -moderate perched groundwater seepage -heavy iron oxide staining [USDA Classification: slightly gravelly SAND] -moderate iron oxide staining -moderate perched groundwater seepage 4.0 15.0 (Continued Next Page)SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 10.0 12.5 15.0 PAGE 1 OF 3 BORING NUMBER B-2 CHECKED BY HTW NOTES SURFACE CONDITIONS Bush AT TIME OF DRILLINGAT TIME OF DRILLING AFTER DRILLING DRILLING CONTRACTOR Geologic Drill Partners DATE STARTED 7/19/22 COMPLETED 7/19/22 GROUND WATER LEVEL: GROUND ELEVATION 170 ft LOGGED BY CGH LATITUDE 47.33705 LONGITUDE -122.33748 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 RECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG 144.0 141.0 SS SS SS 100 100 100 23-29-40 (69) 14-50/6" 18-20-30 (50) MC = 31.7 MC = 26.7 Fines = 34.5 MC = 28.8 SM ML SM Gray silty SAND, very dense, wet -moderate perched groundwater seepage [USDA Classification: very fine sandy LOAM], light perched groundwater seepage -heavy perched groundwater seepage -becomes saturated Gray SILT, very dense, wet Gray silty SAND, very dense, wet 26.0 29.0 (Continued Next Page)SAMPLE TYPENUMBERDEPTH(ft)15.0 17.5 20.0 22.5 25.0 27.5 30.0 PAGE 2 OF 3 BORING NUMBER B-2 CHECKED BY HTW NOTES SURFACE CONDITIONS Bush AT TIME OF DRILLINGAT TIME OF DRILLING AFTER DRILLING DRILLING CONTRACTOR Geologic Drill Partners DATE STARTED 7/19/22 COMPLETED 7/19/22 GROUND WATER LEVEL: GROUND ELEVATION 170 ft LOGGED BY CGH LATITUDE 47.33705 LONGITUDE -122.33748 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 RECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG 138.5 SS 100 16-24- 50/5"MC = 30.9 SM Gray silty SAND, very dense, wet (continued) -heavy perched groundwater seepage Boring terminated at 31.5 feet below existing grade. Groundwater seepage encountered at 7.5 feet to BOH during drilling. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. 31.5SAMPLE TYPENUMBERDEPTH(ft)30.0 PAGE 3 OF 3 BORING NUMBER B-2 CHECKED BY HTW NOTES SURFACE CONDITIONS Bush AT TIME OF DRILLINGAT TIME OF DRILLING AFTER DRILLING DRILLING CONTRACTOR Geologic Drill Partners DATE STARTED 7/19/22 COMPLETED 7/19/22 GROUND WATER LEVEL: GROUND ELEVATION 170 ft LOGGED BY CGH LATITUDE 47.33705 LONGITUDE -122.33748 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 RECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG 174.5 172.0 170.5 168.0 165.5 MC = 32.0 MC = 20.8 Fines = 38.3 MC = 20.0 MC = 21.7 TPSL SM ML SM SP- SM Dark brown TOPSOIL, roots to 7' Brown silty SAND, loose to medium dense, moist to wet Gray sandy SILT, medium dense, wet Gray silty SAND, medium dense, wet [USDA Classification: slightly gravelly fine sandy LOAM] Brown poorly graded SAND with silt, medium dense, wet -oxidized Test pit terminated at 9.5 feet below existing grade. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. 0.5 3.0 4.5 7.0 9.5SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 PAGE 1 OF 1 TEST PIT NUMBER TP-1 CHECKED BY HTW NOTES SURFACE CONDITIONS Brush AT TIME OF EXCAVATIONAT TIME OF EXCAVATION AFTER EXCAVATION EXCAVATION CONTRACTOR NW Excavating DATE STARTED 7/15/22 COMPLETED 7/15/22 GROUND WATER LEVEL: GROUND ELEVATION 175 ft LOGGED BY CGH LATITUDE 47.33703 LONGITUDE -122.33776 PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GENERAL BH / TP / WELL - 8670.GPJ - GINT US.GDT - 8/30/23Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 TESTS U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOG Earth Solutions NW, LLC Appendix B Laboratory Test Results ES-8670 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 3 D100 140 Specimen Identification 1 fine 6 HYDROMETER 304 26.5 99.1 12.4 83.7 94.7 101/2 COBBLES Specimen Identification 4 coarse 20 401.5 8 14 USDA: Gray Slightly Gravelly Sandy Loam. USCS: SM. USDA: Brown Loam. USCS: ML. USDA: Gray Slightly Gravelly Sand. USCS: SM. USDA: Gray Loam. USCS: ML with Sand. USDA: Gray Loam. USCS: ML. 6 60 PERCENT FINER BY WEIGHTD10 0.099 0.191 0.329 0.338 GRAIN SIZE DISTRIBUTION 100 5.46 LL B-01 B-01 B-01 B-01 B-01 3/4 U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS GRAVEL SAND 37.5 1.18 4.75 1.18 2 %Silt 1.75 B-01 B-01 B-01 B-01 B-01 2 2003 Cc CuClassification %Clay 16 PID60 D30 coarse SILT OR CLAYfinemedium GRAIN SIZE IN MILLIMETERS 3/8 50 2.5ft. 7.5ft. 20.0ft. 30.0ft. 50.0ft. 2.50ft. 7.50ft. 20.00ft. 30.00ft. 50.00ft. PL PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GRAIN SIZE USDA ES-8670 REDONDO BAY LOT 35.GPJ GINT US LAB.GDT 7/22/22Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 3 D100 140 Specimen Identification 1 fine 6 HYDROMETER 304 29.1 12.3 34.5 38.3 101/2 COBBLES Specimen Identification 4 coarse 20 401.5 8 14 USDA: Gray Slightly Gravelly Sandy Loam. USCS: SM. USDA: Gray Slightly Gravelly Sand. USCS: SM. USDA: Gray Very Fine Sandy Loam. USCS: SM. USDA: Gray Slightly Gravelly Fine Sandy Loam. USCS: SM. 6 60 PERCENT FINER BY WEIGHTD10 0.08 0.197 0.225 0.339 0.126 0.13 GRAIN SIZE DISTRIBUTION 100 5.60 LL B-02 B-02 B-02 TP-01 3/4 U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS GRAVEL SAND 9.5 4.75 2 4.75 %Silt 1.89 B-02 B-02 B-02 TP-01 2 2003 Cc CuClassification %Clay 16 PID60 D30 coarse SILT OR CLAYfinemedium GRAIN SIZE IN MILLIMETERS 3/8 50 5.0ft. 10.0ft. 20.0ft. 4.5ft. 5.00ft. 10.00ft. 20.00ft. 4.50ft. PL PROJECT NUMBER ES-8670 PROJECT NAME Redondo Bay Lot 35 GRAIN SIZE USDA ES-8670 REDONDO BAY LOT 35.GPJ GINT US LAB.GDT 7/22/22Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 Earth Solutions NW, LLC Appendix C Slope/W Output ES-8670 1.63 Distance 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200Elevation100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 Color Name Unit Weight (pcf) Effective Cohesion (psf) Effective Friction Angle (°) Piezometric Surface Medium Dense Silty Sand 125 25 32 Medium Dense to Dense Sandy Silt 125 100 32 Very Dense Silt 120 250 32 2 Very Dense Silty Sand 125 125 36 1 Pre-Existing: Static Condition 8/21/23, 10:33 AM Pre-Existing - Static (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Static (2).html 1/7 P re -Exi sti ng - Static (2) Report generated using GeoStudio 2022.1. Copyright © 2022 Bentley Systems, Incorporated. File Informaon File Version: 11.04 Title: Penwell Property Created By: Chase Halsen Last Edited By: Chase Halsen Revision Number: 30 Date: 08/21/2023 Time: 10:32:51 AM Tool Version: 11.4.2.250 File Name: Updated Runs 08-18-23.gsz Directory: C:\Users\chase.halsen\Desktop\Project Files\8670\Slope Stability\ Last Solved Date: 08/21/2023 Last Solved Time: 10:32:53 AM Project Sengs Unit System: U.S. Customary Units Analysis Sengs Pre-Exisng - Stac (2) Kind: SLOPE/W Analysis Type: Morgenstern-Price Sengs Side Funcon Interslice force funcon opon: Half-Sine PWP Condions from: Piezometric Surfaces Apply Phreac Correcon: No Use Staged Rapid Drawdown: No Unit Weight of Water: 62.430189 pcf Slip Surface Direcon of movement: Le to Right Use Passive Mode: No Slip Surface Opon: Entry and Exit Crical slip surfaces saved: 1 Opmize Crical Slip Surface Locaon: No Tension Crack Opon: (none) Distribuon F of S Calculaon Opon: Constant Convergence Geometry Sengs Minimum Slip Surface Depth: 3 8/21/23, 10:33 AM Pre-Existing - Static (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Static (2).html 2/7 Number of Slices: 30 Factor of Safety Convergence Sengs Maximum Number of Iteraons: 100 Tolerable difference in F of S: 0.001 Under-Relaxaon Criteria Inial Rate: 1 Minimum Rate: 0.1 Rate Reducon Factor: 0.65 Reducon Frequency (iteraons): 50 Soluon Sengs Search Method: Root Finder Tolerable difference between starng and converged F of S: 3 Maximum iteraons to calculate converged lambda: 20 Max Absolute Lambda: 2 Materials Medium Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 25 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Medium Dense to Dense Sandy Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 100 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Very Dense Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 120 pcf Effecve Cohesion: 250 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 2 Very Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 125 psf Effecve Fricon Angle: 36 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 1 8/21/23, 10:33 AM Pre-Existing - Static (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Static (2).html 3/7 Slip Surface Entry and Exit Le Type: Range Le-Zone Le Coordinate: (0, 202) Le-Zone Right Coordinate: (99, 170.33679) Le-Zone Increment: 20 Right Type: Range Right-Zone Le Coordinate: (102.40444, 168.46976) Right-Zone Right Coordinate: (182.65, 136) Right-Zone Increment: 20 Radius Increments: 4 Slip Surface Limits Le Coordinate: (0, 202) Right Coordinate: (182.65, 136) Piezometric Surfaces Piezometric Surface 1 Coordinates X Y Coordinate 1 0 175 Coordinate 2 90 175 Piezometric Surface 2 Coordinates X Y Coordinate 1 0 160 Coordinate 2 117.65 160 Geometry Name: 2D Geometry (2) Sengs View: 2D Element Thickness: 1 Points X Y Point 1 0 202 Point 2 18 200 Point 3 26 198 8/21/23, 10:33 AM Pre-Existing - Static (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Static (2).html 4/7 Point 4 33 196 Point 5 40 194 Point 6 47 192 Point 7 53 190 Point 8 59 188 Point 9 64 186 Point 10 69 184 Point 11 75 182 Point 12 81 180 Point 13 85 178 Point 14 99.65 170 Point 15 117.65 160 Point 16 130.65 154 Point 17 136.65 152 Point 18 142.65 150 Point 19 146.65 148 Point 20 160.65 146 Point 21 171.65 142 Point 22 174.65 140 Point 23 182.65 136 Point 24 0 185 Point 25 66 185 Point 26 0 175 Point 27 90 175 Point 28 0 160 Point 29 0 150 Point 30 0 140 Point 31 182.65 100 Point 32 0 100 Regions Material Points Area Region 1 Medium Dense Silty Sand 1,24,25,9,8,7,6,5,4,3,2 681 ² Region 2 Medium Dense to Dense Sandy Silt 24,26,27,13,12,11,10,25 796 ² Region 3 Very Dense Silty Sand 26,28,15,14,27 1,560.6 ² Region 4 Very Dense Silt 28,29,18,17,16,15 1,291.5 ² Region 5 Very Dense Silty Sand 29,30,18 713.25 ² Region 6 Very Dense Silt 30,18,19,20,21,22,23,31,32 8,184.2 ² Slip Results Slip Surfaces Analysed: 1976 of 2205 converged Current Slip Surface Slip Surface: 1,303 8/21/23, 10:33 AM Pre-Existing - Static (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Static (2).html 5/7 Factor of Safety: 1.63 Volume: 742.90606 ³ Weight: 91,805.306 lbf Resisng Moment: 4,148,166.9 lbf· Acvang Moment: 2,538,313.3 lbf· Resisng Force: 53,193.605 lbf Acvang Force: 32,553.883 lbf Slip Rank: 1 of 2,205 slip surfaces Exit: (133.64053, 153.00316) Entry: (60.842715, 187.26291) Radius: 69.774632 Center: (121.51762, 221.71658) Slip Slices X Y PWP Base Normal Stress Friconal Strength Cohesive Strength Sucon Strength Base Material Slice 1 61.513722 186.13146 0 psf 49.09799 psf 30.679829 psf 25 psf 0 psf Medium Dense Silty Sand Slice 2 63.092364 183.60846 0 psf 152.43812 psf 95.25391 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 3 65 180.83447 0 psf 305.74949 psf 191.05348 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 4 67.5 177.61476 0 psf 485.89888 psf 303.62332 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 5 69.345202 175.38875 0 psf 620.24836 psf 387.57419 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 6 71.017803 173.60666 86.986399 psf 713.9727 psf 455.53221 psf 125 psf 0 psf Very Dense Silty Sand Slice 7 73.672601 170.96202 252.092 psf 902.86186 psf 472.81198 psf 125 psf 0 psf Very Dense 8/21/23, 10:33 AM Pre-Existing - Static (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Static (2).html 6/7 Silty Sand Slice 8 76.5 168.44317 409.34426 psf 1,074.5706 psf 483.31523 psf 125 psf 0 psf Very Dense Silty Sand Slice 9 79.5 166.04354 559.15339 psf 1,234.8535 psf 490.92486 psf 125 psf 0 psf Very Dense Silty Sand Slice 10 82 164.22411 672.74104 psf 1,342.3711 psf 486.51469 psf 125 psf 0 psf Very Dense Silty Sand Slice 11 84 162.89889 755.47451 psf 1,402.2566 psf 469.91467 psf 125 psf 0 psf Very Dense Silty Sand Slice 12 85.991673 161.67427 831.92763 psf 1,447.1421 psf 446.97944 psf 125 psf 0 psf Very Dense Silty Sand Slice 13 87.975018 160.54376 902.50584 psf 1,477.0148 psf 417.40519 psf 125 psf 0 psf Very Dense Silty Sand Slice 14 89.483346 159.73298 16.669898 psf 1,475.5216 psf 911.59172 psf 250 psf 0 psf Very Dense Silt Slice 15 91.20625 158.88405 69.66876 psf 1,515.941 psf 903.73122 psf 250 psf 0 psf Very Dense Silt Slice 16 93.61875 157.77582 138.8557 psf 1,571.1111 psf 894.97248 psf 250 psf 0 psf Very Dense Silt Slice 17 96.03125 156.77611 201.26824 psf 1,614.9824 psf 883.38662 psf 250 psf 0 psf Very Dense Silt Slice 18 98.44375 155.87995 257.21556 psf 1,646.2157 psf 867.94364 psf 250 psf 0 psf Very Dense Silt Slice 19 100.93571 155.06019 308.39298 psf 1,657.6042 psf 843.08076 psf 250 psf 0 psf Very Dense Silt Slice 20 103.50714 154.31962 354.62748 psf 1,645.2073 psf 806.44376 psf 250 psf 0 psf Very Dense Silt Slice 21 106.07857 153.68426 394.29295 psf 1,610.8379 psf 760.18165 psf 250 psf 0 psf Very Dense Silt 8/21/23, 10:33 AM Pre-Existing - Static (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Static (2).html 7/7 Slice 22 108.65 153.15119 427.57232 psf 1,552.123 psf 702.69725 psf 250 psf 0 psf Very Dense Silt Slice 23 111.22143 152.71805 454.61381 psf 1,467.1887 psf 632.72701 psf 250 psf 0 psf Very Dense Silt Slice 24 113.79286 152.38294 475.53452 psf 1,354.9915 psf 549.54572 psf 250 psf 0 psf Very Dense Silt Slice 25 116.36429 152.14446 490.42301 psf 1,215.604 psf 453.14335 psf 250 psf 0 psf Very Dense Silt Slice 26 118.95 152.00134 0 psf 1,115.2675 psf 696.89648 psf 250 psf 0 psf Very Dense Silt Slice 27 121.55 151.95407 0 psf 952.49222 psf 595.1832 psf 250 psf 0 psf Very Dense Silt Slice 28 124.15 152.00376 0 psf 766.72903 psf 479.10547 psf 250 psf 0 psf Very Dense Silt Slice 29 126.75 152.15063 0 psf 563.11485 psf 351.87321 psf 250 psf 0 psf Very Dense Silt Slice 30 129.35 152.39529 0 psf 347.3773 psf 217.06543 psf 250 psf 0 psf Very Dense Silt Slice 31 132.14526 152.77266 0 psf 132.5938 psf 82.853803 psf 250 psf 0 psf Very Dense Silt 1.00 Distance 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200Elevation100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 Color Name Unit Weight (pcf) Effective Cohesion (psf) Effective Friction Angle (°) Piezometric Surface Medium Dense Silty Sand 125 25 32 Medium Dense to Dense Sandy Silt 125 100 32 Very Dense Silt 120 500 32 2 Very Dense Silty Sand 125 250 36 1 Color Name Unit Weight (pcf) Effective Cohesion (psf) Effective Friction Angle (°) Piezometric Surface Medium Dense Silty Sand 125 25 32 Medium Dense to Dense Sandy Silt 125 100 32 Very Dense Silt 120 500 32 2 Very Dense Silty Sand 125 250 36 1 Pre-Existing: Seismic Condition 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 1/8 P re -Exi sti ng - Seismic (2) Report generated using GeoStudio 2022.1. Copyright © 2022 Bentley Systems, Incorporated. File Informaon File Version: 11.04 Title: Penwell Property Created By: Chase Halsen Last Edited By: Chase Halsen Revision Number: 31 Date: 08/21/2023 Time: 10:35:12 AM Tool Version: 11.4.2.250 File Name: Updated Runs 08-18-23.gsz Directory: C:\Users\chase.halsen\Desktop\Project Files\8670\Slope Stability\ Last Solved Date: 08/21/2023 Last Solved Time: 10:35:14 AM Project Sengs Unit System: U.S. Customary Units Analysis Sengs Pre-Exisng - Seismic (2) Kind: SLOPE/W Analysis Type: Morgenstern-Price Sengs Side Funcon Interslice force funcon opon: Half-Sine PWP Condions from: Piezometric Surfaces Apply Phreac Correcon: No Use Staged Rapid Drawdown: No Unit Weight of Water: 62.430189 pcf Slip Surface Direcon of movement: Le to Right Use Passive Mode: No Slip Surface Opon: Entry and Exit Crical slip surfaces saved: 1 Opmize Crical Slip Surface Locaon: No Tension Crack Opon: (none) Distribuon F of S Calculaon Opon: Constant Convergence Geometry Sengs Minimum Slip Surface Depth: 3 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 2/8 Number of Slices: 30 Factor of Safety Convergence Sengs Maximum Number of Iteraons: 100 Tolerable difference in F of S: 0.001 Under-Relaxaon Criteria Inial Rate: 1 Minimum Rate: 0.1 Rate Reducon Factor: 0.65 Reducon Frequency (iteraons): 50 Soluon Sengs Search Method: Root Finder Tolerable difference between starng and converged F of S: 3 Maximum iteraons to calculate converged lambda: 20 Max Absolute Lambda: 2 Materials Medium Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 25 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Medium Dense to Dense Sandy Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 100 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Very Dense Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 120 pcf Effecve Cohesion: 500 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 2 Very Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 250 psf Effecve Fricon Angle: 36 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 1 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 3/8 Slip Surface Entry and Exit Le Type: Range Le-Zone Le Coordinate: (0, 202) Le-Zone Right Coordinate: (99, 170.33679) Le-Zone Increment: 20 Right Type: Range Right-Zone Le Coordinate: (102.77214, 168.26548) Right-Zone Right Coordinate: (182.65, 136) Right-Zone Increment: 20 Radius Increments: 4 Slip Surface Limits Le Coordinate: (0, 202) Right Coordinate: (182.65, 136) Piezometric Surfaces Piezometric Surface 1 Coordinates X Y Coordinate 1 0 175 Coordinate 2 90 175 Piezometric Surface 2 Coordinates X Y Coordinate 1 0 160 Coordinate 2 117.65 160 Seismic Coefficients Horz Seismic Coef.: 0.343 Geometry Name: 2D Geometry (2) Sengs View: 2D Element Thickness: 1 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 4/8 Points X Y Point 1 0 202 Point 2 18 200 Point 3 26 198 Point 4 33 196 Point 5 40 194 Point 6 47 192 Point 7 53 190 Point 8 59 188 Point 9 64 186 Point 10 69 184 Point 11 75 182 Point 12 81 180 Point 13 85 178 Point 14 99.65 170 Point 15 117.65 160 Point 16 130.65 154 Point 17 136.65 152 Point 18 142.65 150 Point 19 146.65 148 Point 20 160.65 146 Point 21 171.65 142 Point 22 174.65 140 Point 23 182.65 136 Point 24 0 185 Point 25 66 185 Point 26 0 175 Point 27 90 175 Point 28 0 160 Point 29 0 150 Point 30 0 140 Point 31 182.65 100 Point 32 0 100 Regions Material Points Area Region 1 Medium Dense Silty Sand 1,24,25,9,8,7,6,5,4,3,2 681 ² Region 2 Medium Dense to Dense Sandy Silt 24,26,27,13,12,11,10,25 796 ² Region 3 Very Dense Silty Sand 26,28,15,14,27 1,560.6 ² Region 4 Very Dense Silt 28,29,18,17,16,15 1,291.5 ² Region 5 Very Dense Silty Sand 29,30,18 713.25 ² Region 6 Very Dense Silt 30,18,19,20,21,22,23,31,32 8,184.2 ² 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 5/8 Slip Results Slip Surfaces Analysed: 1974 of 2205 converged Current Slip Surface Slip Surface: 352 Factor of Safety: 1.00 Volume: 1,326.3536 ³ Weight: 165,216.42 lbf Resisng Moment: 18,769,043 lbf· Acvang Moment: 18,736,095 lbf· Resisng Force: 102,714.67 lbf Acvang Force: 102,577.27 lbf Slip Rank: 1 of 2,205 slip surfaces Exit: (129.79825, 154.39312) Entry: (15.611699, 200.26537) Radius: 171.21886 Center: (132.26756, 325.59417) Slip Slices X Y PWP Base Normal Stress Friconal Strength Cohesive Strength Sucon Strength Base Material Slice 1 16.805849 199.17472 0 psf 60.718503 psf 37.941132 psf 25 psf 0 psf Medium Dense Silty Sand Slice 2 20 196.34683 0 psf 226.40536 psf 141.47377 psf 25 psf 0 psf Medium Dense Silty Sand Slice 3 24 192.97679 0 psf 393.65937 psf 245.98568 psf 25 psf 0 psf Medium Dense Silty Sand Slice 4 27.75 189.99514 0 psf 524.75779 psf 327.90506 psf 25 psf 0 psf Medium Dense Silty Sand Slice 5 31.25 187.36735 0 psf 627.14129 psf 391.88137 psf 25 psf 0 psf Medium Dense Silty Sand Slice 6 33.773832 185.54422 0 psf 695.42604 psf 434.55042 psf 25 psf 0 psf Medium Dense Silty Sand Slice 7 37.273832 183.18156 0 psf 768.72969 psf 480.35562 psf 100 psf 0 psf Medium Dense to 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 6/8 Dense Sandy Silt Slice 8 41.75 180.27308 0 psf 883.22526 psf 551.90039 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 9 45.25 178.15024 0 psf 968.53782 psf 605.2096 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 10 48.898984 176.05872 0 psf 1,050.7445 psf 656.57802 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 11 51.898984 174.41469 36.541116 psf 1,136.6913 psf 799.30589 psf 250 psf 0 psf Very Dense Silty Sand Slice 12 54.5 173.0646 120.8275 psf 1,201.8902 psf 785.43804 psf 250 psf 0 psf Very Dense Silty Sand Slice 13 57.5 171.57167 214.03124 psf 1,273.147 psf 769.49264 psf 250 psf 0 psf Very Dense Silty Sand Slice 14 61.5 169.70859 330.34349 psf 1,349.2342 psf 740.26742 psf 250 psf 0 psf Very Dense Silty Sand Slice 15 65 168.14643 427.86976 psf 1,399.7872 psf 706.13934 psf 250 psf 0 psf Very Dense Silty Sand Slice 16 67.5 167.1062 492.81127 psf 1,440.6062 psf 688.6133 psf 250 psf 0 psf Very Dense Silty Sand Slice 17 70.5 165.91299 567.30395 psf 1,508.6398 psf 683.92052 psf 250 psf 0 psf Very Dense Silty Sand Slice 18 73.5 164.78459 637.75012 psf 1,579.1477 psf 683.96541 psf 250 psf 0 psf Very Dense 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 7/8 Silty Sand Slice 19 76.5 163.71965 704.23444 psf 1,652.4456 psf 688.91575 psf 250 psf 0 psf Very Dense Silty Sand Slice 20 79.5 162.71693 766.83466 psf 1,728.2989 psf 698.54463 psf 250 psf 0 psf Very Dense Silty Sand Slice 21 83 161.63001 834.69079 psf 1,784.0802 psf 689.77176 psf 250 psf 0 psf Very Dense Silty Sand Slice 22 86.87103 160.51453 904.33069 psf 1,793.5001 psf 646.01936 psf 250 psf 0 psf Very Dense Silty Sand Slice 23 89.37103 159.83723 10.161901 psf 2,113.2764 psf 1,314.1718 psf 500 psf 0 psf Very Dense Silt Slice 24 91.608333 159.28126 44.871106 psf 2,083.4999 psf 1,273.8766 psf 500 psf 0 psf Very Dense Silt Slice 25 94.825 158.52761 91.921735 psf 2,027.2833 psf 1,209.3481 psf 500 psf 0 psf Very Dense Silt Slice 26 98.041667 157.83901 134.9107 psf 1,943.052 psf 1,129.8521 psf 500 psf 0 psf Very Dense Silt Slice 27 101.45 157.1815 175.95954 psf 1,814.9284 psf 1,024.1414 psf 500 psf 0 psf Very Dense Silt Slice 28 105.05 156.56228 214.61728 psf 1,639.1737 psf 890.16166 psf 500 psf 0 psf Very Dense Silt Slice 29 108.65 156.02175 248.363 psf 1,432.2774 psf 739.79181 psf 500 psf 0 psf Very Dense Silt Slice 30 112.25 155.55914 277.24356 psf 1,199.1703 psf 576.0838 psf 500 psf 0 psf Very Dense Silt Slice 31 115.85 155.17383 301.29861 psf 945.79017 psf 402.72302 psf 500 psf 0 psf Very Dense Silt Slice 32 119.67471 154.8511 0 psf 708.77901 psf 442.89428 psf 500 psf 0 psf Very Dense Silt Slice 33 123.72412 154.60061 0 psf 424.23211 psf 265.08965 psf 500 psf 0 psf Very Dense Silt 8/21/23, 10:37 AM Pre-Existing - Seismic (2) file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Pre Existing/Updated Runs 08-18-23 - Pre-Existing - Seismic (2).html 8/8 Slice 34 127.77354 154.44628 0 psf 135.94436 psf 84.947464 psf 500 psf 0 psf Very Dense Silt 1.58 Distance 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200Elevation100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 Color Name Unit Weight (pcf) Effective Cohesion (psf) Effective Friction Angle (°) Piezometric Surface Fill 125 0 32 Medium Dense Silty Sand 125 25 32 Medium Dense to Dense Sandy Silt 125 100 32 Very Dense Silt 120 250 32 2 Very Dense Silty Sand 125 125 36 1 Post-Construction: Static Condition 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…1/8 Post-Con struci ton - Stat ic Report generated using GeoStudio 2022.1. Copyright © 2022 Bentley Systems, Incorporated. File Informaon File Version: 11.04 Title: Penwell Property Created By: Chase Halsen Last Edited By: Chase Halsen Revision Number: 33 Date: 08/22/2023 Time: 11:55:01 AM Tool Version: 11.4.2.250 File Name: Updated Runs 08-18-23.gsz Directory: C:\Users\chase.halsen\Desktop\Project Files\8670\Slope Stability\ Last Solved Date: 08/22/2023 Last Solved Time: 11:55:03 AM Project Sengs Unit System: U.S. Customary Units Analysis Sengs Post-Construciton - Stac Kind: SLOPE/W Analysis Type: Morgenstern-Price Sengs Side Funcon Interslice force funcon opon: Half-Sine PWP Condions from: Piezometric Surfaces Apply Phreac Correcon: No Use Staged Rapid Drawdown: No Unit Weight of Water: 62.430189 pcf Slip Surface Direcon of movement: Le to Right Use Passive Mode: No Slip Surface Opon: Entry and Exit Crical slip surfaces saved: 1 Opmize Crical Slip Surface Locaon: No Tension Crack Opon: (none) Distribuon F of S Calculaon Opon: Constant Convergence Geometry Sengs Minimum Slip Surface Depth: 3 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…2/8 Number of Slices: 30 Factor of Safety Convergence Sengs Maximum Number of Iteraons: 100 Tolerable difference in F of S: 0.001 Under-Relaxaon Criteria Inial Rate: 1 Minimum Rate: 0.1 Rate Reducon Factor: 0.65 Reducon Frequency (iteraons): 50 Soluon Sengs Search Method: Root Finder Tolerable difference between starng and converged F of S: 3 Maximum iteraons to calculate converged lambda: 20 Max Absolute Lambda: 2 Materials Medium Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 25 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Medium Dense to Dense Sandy Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 100 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Very Dense Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 120 pcf Effecve Cohesion: 250 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 2 Very Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 125 psf Effecve Fricon Angle: 36 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 1 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…3/8 Fill Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 0 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Slip Surface Entry and Exit Le Type: Range Le-Zone Le Coordinate: (0, 202) Le-Zone Right Coordinate: (75, 182) Le-Zone Increment: 20 Right Type: Range Right-Zone Le Coordinate: (77, 181.33333) Right-Zone Right Coordinate: (140, 151.0001) Right-Zone Increment: 20 Radius Increments: 4 Slip Surface Limits Le Coordinate: (0, 202) Right Coordinate: (183, 100) Piezometric Surfaces Piezometric Surface 1 Coordinates X Y Coordinate 1 0 175 Coordinate 2 90 175 Piezometric Surface 2 Coordinates X Y Coordinate 1 0 160 Coordinate 2 117.65 160 Surcharge Loads Surcharge Load 1 Surcharge (Unit Weight): 375 pcf Direcon: Vercal 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…4/8 Coordinates X Y 6 194 40 194 Surcharge Load 2 Surcharge (Unit Weight): 375 pcf Direcon: Vercal Coordinates X Y 40 185 75 185 Geometry Name: 2D Geometry Sengs View: 2D Element Thickness: 1 Points X Y Point 1 0 202 Point 2 6 201 Point 3 6 192.5 Point 4 40 192.5 Point 5 40 184 Point 6 75 184 Point 7 75 182 Point 8 81 180 Point 9 85 178 Point 10 99.65 170 Point 11 117.65 160 Point 12 130.65 154 Point 13 136.65 152 Point 14 142.65 150 Point 15 146.65 148 Point 16 160.65 146 Point 17 166.65 144 Point 18 171.65 142 Point 19 174.65 140 Point 20 182.65 136 Point 21 0 185 Point 22 40 185 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…5/8 Point 23 0 175 Point 24 90 175 Point 25 0 160 Point 26 0 150 Point 27 140.00035 151 Point 28 0 140 Point 29 0 100 Point 30 183 100 Point 31 67 184 Regions Material Points Area Region 1 Medium Dense Silty Sand 1,21,22,4,3,2 354 ² Region 2 Medium Dense to Dense Sandy Silt 21,23,24,9,8,7,31,5,22 766.5 ² Region 3 Very Dense Silty Sand 23,25,11,10,24 1,560.6 ² Region 4 Very Dense Silt 25,26,27,13,12,11 1,220.5 ² Region 5 Very Dense Silty Sand 26,28,27 700 ² Region 6 Very Dense Silt 28,29,30,20,19,18,17,16,15,14,27 8,276.1 ² Region 7 Fill 31,7,6 8 ² Slip Results Slip Surfaces Analysed: 1060 of 2205 converged Current Slip Surface Slip Surface: 1,983 Factor of Safety: 1.58 Volume: 622.90702 ³ Weight: 76,923.908 lbf Resisng Moment: 3,336,903.6 lbf· Acvang Moment: 2,114,081.3 lbf· Resisng Force: 46,809.216 lbf Acvang Force: 29,660.1 lbf Slip Rank: 1 of 2,205 slip surfaces Exit: (133.3147, 153.11177) Entry: (67.591724, 184) Radius: 62.948358 Center: (122.32471, 215.09334) Slip Slices X Y PWP Base Normal Stress Friconal Strength Cohesive Strength Sucon Strength Base Material Slice 1 67.640908 183.91374 0 psf 227.25273 psf 142.00327 psf 0 psf 0 psf Fill Slice 2 68.707772 182.17014 0 psf 293.90117 psf 183.64983 psf 100 psf 0 psf Medium Dense 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…6/8 to Dense Sandy Silt Slice 3 70.743129 179.05616 0 psf 532.24551 psf 332.58391 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 4 72.778487 176.29975 0 psf 745.24048 psf 465.67794 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 5 74.398083 174.29295 44.141169 psf 872.31097 psf 601.70058 psf 125 psf 0 psf Very Dense Silty Sand Slice 6 76 172.49834 156.17904 psf 640.8637 psf 352.14402 psf 125 psf 0 psf Very Dense Silty Sand Slice 7 78 170.41861 286.01681 psf 785.97688 psf 363.24226 psf 125 psf 0 psf Very Dense Silty Sand Slice 8 80 168.51772 404.6901 psf 912.8924 psf 369.23058 psf 125 psf 0 psf Very Dense Silty Sand Slice 9 82 166.77443 513.52367 psf 1,012.6592 psf 362.64317 psf 125 psf 0 psf Very Dense Silty Sand Slice 10 84 165.17218 613.55294 psf 1,087.8964 psf 344.63072 psf 125 psf 0 psf Very Dense Silty Sand Slice 11 86.25 163.52995 716.07753 psf 1,150.9785 psf 315.97406 psf 125 psf 0 psf Very Dense Silty Sand Slice 12 88.75 161.86694 819.89964 psf 1,201.8483 psf 277.50196 psf 125 psf 0 psf Very Dense Silty Sand Slice 13 90.937217 160.53922 0 psf 1,222.2386 psf 888.00835 psf 125 psf 0 psf Very Dense Silty Sand 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…7/8 Slice 14 92.84638 159.48477 32.166051 psf 1,288.6197 psf 785.11938 psf 250 psf 0 psf Very Dense Silt Slice 15 94.790272 158.49668 93.852488 psf 1,348.6994 psf 784.11539 psf 250 psf 0 psf Very Dense Silt Slice 16 96.734163 157.59127 150.37716 psf 1,401.9224 psf 782.05227 psf 250 psf 0 psf Very Dense Silt Slice 17 98.678054 156.76469 201.98085 psf 1,447.6825 psf 778.40078 psf 250 psf 0 psf Very Dense Silt Slice 18 100.775 155.96068 252.1756 psf 1,482.5534 psf 768.82538 psf 250 psf 0 psf Very Dense Silt Slice 19 103.025 155.18825 300.39833 psf 1,502.8109 psf 751.35075 psf 250 psf 0 psf Very Dense Silt Slice 20 105.275 154.50921 342.79109 psf 1,506.9294 psf 727.43436 psf 250 psf 0 psf Very Dense Silt Slice 21 107.525 153.92044 379.54835 psf 1,492.3234 psf 695.33903 psf 250 psf 0 psf Very Dense Silt Slice 22 109.775 153.41934 410.83175 psf 1,456.4356 psf 653.36583 psf 250 psf 0 psf Very Dense Silt Slice 23 112.025 153.0038 436.77402 psf 1,397.0443 psf 600.04344 psf 250 psf 0 psf Very Dense Silt Slice 24 114.275 152.6721 457.48199 psf 1,312.6028 psf 534.33876 psf 250 psf 0 psf Very Dense Silt Slice 25 116.525 152.42291 473.03887 psf 1,202.5647 psf 455.85836 psf 250 psf 0 psf Very Dense Silt Slice 26 118.73333 152.25689 0 psf 1,143.439 psf 714.49998 psf 250 psf 0 psf Very Dense Silt Slice 27 120.9 152.17044 0 psf 1,013.5131 psf 633.3133 psf 250 psf 0 psf Very Dense Silt Slice 28 123.06667 152.15868 0 psf 861.72266 psf 538.46408 psf 250 psf 0 psf Very Dense Silt Slice 29 125.23333 152.22157 0 psf 692.18643 psf 432.52609 psf 250 psf 0 psf Very Dense Silt Slice 30 127.4 152.35933 0 psf 509.78184 psf 318.54705 psf 250 psf 0 psf Very Dense Silt 8/22/23, 11:56 AM Post-Construciton - Static file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Stat…8/8 Slice 31 129.56667 152.57246 0 psf 319.65464 psf 199.74238 psf 250 psf 0 psf Very Dense Silt Slice 32 131.98235 152.90486 0 psf 126.13995 psf 78.820986 psf 250 psf 0 psf Very Dense Silt 1.08 Distance 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200Elevation100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 Factor of Safety ≤ 1.00 - 1.10 1.10 - 1.20 ≥ 1.20 Color Name Unit Weight (pcf) Effective Cohesion (psf) Effective Friction Angle (°) Piezometric Surface Fill 125 0 32 Medium Dense Silty Sand 125 25 32 Medium Dense to Dense Sandy Silt 125 100 32 Very Dense Silt 120 500 32 2 Very Dense Silty Sand 125 250 36 1 Post-Construction: Seismic Condition 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…1/8 Post-Con struci ton - Sei smic Report generated using GeoStudio 2022.1. Copyright © 2022 Bentley Systems, Incorporated. File Informaon File Version: 11.04 Title: Penwell Property Created By: Chase Halsen Last Edited By: Chase Halsen Revision Number: 31 Date: 08/21/2023 Time: 10:35:12 AM Tool Version: 11.4.2.250 File Name: Updated Runs 08-18-23.gsz Directory: C:\Users\chase.halsen\Desktop\Project Files\8670\Slope Stability\ Last Solved Date: 08/21/2023 Last Solved Time: 10:35:13 AM Project Sengs Unit System: U.S. Customary Units Analysis Sengs Post-Construciton - Seismic Kind: SLOPE/W Analysis Type: Morgenstern-Price Sengs Side Funcon Interslice force funcon opon: Half-Sine PWP Condions from: Piezometric Surfaces Apply Phreac Correcon: No Use Staged Rapid Drawdown: No Unit Weight of Water: 62.430189 pcf Slip Surface Direcon of movement: Le to Right Use Passive Mode: No Slip Surface Opon: Entry and Exit Crical slip surfaces saved: 1 Opmize Crical Slip Surface Locaon: No Tension Crack Opon: (none) Distribuon F of S Calculaon Opon: Constant Convergence Geometry Sengs Minimum Slip Surface Depth: 3 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…2/8 Number of Slices: 30 Factor of Safety Convergence Sengs Maximum Number of Iteraons: 100 Tolerable difference in F of S: 0.001 Under-Relaxaon Criteria Inial Rate: 1 Minimum Rate: 0.1 Rate Reducon Factor: 0.65 Reducon Frequency (iteraons): 50 Soluon Sengs Search Method: Root Finder Tolerable difference between starng and converged F of S: 3 Maximum iteraons to calculate converged lambda: 20 Max Absolute Lambda: 2 Materials Medium Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 25 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Medium Dense to Dense Sandy Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 100 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Very Dense Silt Slope Stability Material Model: Mohr-Coulomb Unit Weight: 120 pcf Effecve Cohesion: 500 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 2 Very Dense Silty Sand Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 250 psf Effecve Fricon Angle: 36 ° Phi-B: 0 ° Pore Water Pressure Piezometric Surface: 1 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…3/8 Fill Slope Stability Material Model: Mohr-Coulomb Unit Weight: 125 pcf Effecve Cohesion: 0 psf Effecve Fricon Angle: 32 ° Phi-B: 0 ° Slip Surface Entry and Exit Le Type: Range Le-Zone Le Coordinate: (0.12622, 201.97896) Le-Zone Right Coordinate: (75, 182) Le-Zone Increment: 20 Right Type: Range Right-Zone Le Coordinate: (77, 181.33333) Right-Zone Right Coordinate: (140, 151.0001) Right-Zone Increment: 20 Radius Increments: 4 Slip Surface Limits Le Coordinate: (0, 202) Right Coordinate: (183, 100) Piezometric Surfaces Piezometric Surface 1 Coordinates X Y Coordinate 1 0 175 Coordinate 2 90 175 Piezometric Surface 2 Coordinates X Y Coordinate 1 0 160 Coordinate 2 117.65 160 Seismic Coefficients Horz Seismic Coef.: 0.343 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…4/8 Surcharge Loads Surcharge Load 1 Surcharge (Unit Weight): 375 pcf Direcon: Vercal Coordinates X Y 6 194 40 194 Surcharge Load 2 Surcharge (Unit Weight): 375 pcf Direcon: Vercal Coordinates X Y 40 185 75 185 Geometry Name: 2D Geometry Sengs View: 2D Element Thickness: 1 Points X Y Point 1 0 202 Point 2 6 201 Point 3 6 192.5 Point 4 40 192.5 Point 5 40 184 Point 6 75 184 Point 7 75 182 Point 8 81 180 Point 9 85 178 Point 10 99.65 170 Point 11 117.65 160 Point 12 130.65 154 Point 13 136.65 152 Point 14 142.65 150 Point 15 146.65 148 Point 16 160.65 146 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…5/8 Point 17 166.65 144 Point 18 171.65 142 Point 19 174.65 140 Point 20 182.65 136 Point 21 0 185 Point 22 40 185 Point 23 0 175 Point 24 90 175 Point 25 0 160 Point 26 0 150 Point 27 140.00035 151 Point 28 0 140 Point 29 0 100 Point 30 183 100 Point 31 67 184 Regions Material Points Area Region 1 Medium Dense Silty Sand 1,21,22,4,3,2 354 ² Region 2 Medium Dense to Dense Sandy Silt 21,23,24,9,8,7,31,5,22 766.5 ² Region 3 Very Dense Silty Sand 23,25,11,10,24 1,560.6 ² Region 4 Very Dense Silt 25,26,27,13,12,11 1,220.5 ² Region 5 Very Dense Silty Sand 26,28,27 700 ² Region 6 Very Dense Silt 28,29,30,20,19,18,17,16,15,14,27 8,276.1 ² Region 7 Fill 31,7,6 8 ² Slip Results Slip Surfaces Analysed: 1062 of 2205 converged Current Slip Surface Slip Surface: 732 Factor of Safety: 1.08 Volume: 1,535.5402 ³ Weight: 190,371.02 lbf Resisng Moment: 23,990,785 lbf· Acvang Moment: 22,140,478 lbf· Resisng Force: 133,630.69 lbf Acvang Force: 123,389.77 lbf Slip Rank: 1 of 2,205 slip surfaces Exit: (140, 151.0001) Entry: (19.731639, 192.5) Radius: 168.49785 Center: (130.76035, 319.24444) 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…6/8 Slip Slices X Y PWP Base Normal Stress Friconal Strength Cohesive Strength Sucon Strength Base Material Slice 1 22.030569 190.55759 0 psf 516.00535 psf 322.43593 psf 25 psf 0 psf Medium Dense Silty Sand Slice 2 26.628429 186.80759 0 psf 802.22872 psf 501.28814 psf 25 psf 0 psf Medium Dense Silty Sand Slice 3 30.772799 183.63928 0 psf 1,006.5365 psf 628.95381 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 4 34.46368 180.99314 0 psf 1,196.8009 psf 747.84419 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 5 38.15456 178.49354 0 psf 1,374.0408 psf 858.59596 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 6 41.834023 176.13968 0 psf 755.89776 psf 472.33735 psf 100 psf 0 psf Medium Dense to Dense Sandy Silt Slice 7 45.612376 173.86125 71.092635 psf 928.5263 psf 622.96202 psf 250 psf 0 psf Very Dense Silty Sand Slice 8 49.501035 171.65201 209.0156 psf 1,129.0128 psf 668.4171 psf 250 psf 0 psf Very Dense Silty Sand Slice 9 53.389694 169.57641 338.59564 psf 1,314.6199 psf 709.12315 psf 250 psf 0 psf Very Dense Silty Sand Slice 10 57.278353 167.62895 460.17576 psf 1,491.6581 psf 749.41576 psf 250 psf 0 psf Very Dense 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…7/8 Silty Sand Slice 11 61.167012 165.80475 574.06088 psf 1,666.4331 psf 793.65486 psf 250 psf 0 psf Very Dense Silty Sand Slice 12 65.055671 164.09946 680.52269 psf 1,845.1744 psf 846.16898 psf 250 psf 0 psf Very Dense Silty Sand Slice 13 69 162.48805 781.12344 psf 2,036.62 psf 912.17165 psf 250 psf 0 psf Very Dense Silty Sand Slice 14 73 160.97019 875.88345 psf 2,246.9933 psf 996.16962 psf 250 psf 0 psf Very Dense Silty Sand Slice 15 75.345033 160.12016 928.95131 psf 1,802.093 psf 634.37459 psf 250 psf 0 psf Very Dense Silty Sand Slice 16 78.345033 159.13086 54.260498 psf 2,174.9541 psf 1,325.1565 psf 500 psf 0 psf Very Dense Silt Slice 17 83 157.67053 145.42903 psf 2,279.094 psf 1,333.2619 psf 500 psf 0 psf Very Dense Silt Slice 18 87.5 156.41515 223.80307 psf 2,295.6714 psf 1,294.647 psf 500 psf 0 psf Very Dense Silt Slice 19 92.4125 155.18704 300.47429 psf 2,280.2068 psf 1,237.0741 psf 500 psf 0 psf Very Dense Silt Slice 20 97.2375 154.13331 366.25875 psf 2,243.2219 psf 1,172.8568 psf 500 psf 0 psf Very Dense Silt Slice 21 101.9 153.25229 421.26054 psf 2,149.3678 psf 1,079.8413 psf 500 psf 0 psf Very Dense Silt Slice 22 106.4 152.53232 466.20859 psf 1,995.8799 psf 955.84475 psf 500 psf 0 psf Very Dense Silt Slice 23 110.9 151.93646 503.40837 psf 1,788.889 psf 803.25744 psf 500 psf 0 psf Very Dense Silt Slice 24 115.4 151.46338 532.9425 psf 1,531.3618 psf 623.88161 psf 500 psf 0 psf Very Dense Silt Slice 25 119.21931 151.14965 0 psf 1,416.1029 psf 884.87931 psf 500 psf 0 psf Very Dense 8/21/23, 10:40 AM Post-Construciton - Seismic file:///C:/Users/chase.halsen/Desktop/Project Files/8670/Slope Stability/Print outs/Post Construction/Updated Runs 08-18-23 - Post-Construciton - Sei…8/8 Silt Slice 26 122.35793 150.96355 0 psf 1,195.9893 psf 747.33709 psf 500 psf 0 psf Very Dense Silt Slice 27 125.60793 150.83377 0 psf 915.52615 psf 665.16868 psf 250 psf 0 psf Very Dense Silty Sand Slice 28 128.96931 150.76449 0 psf 667.22684 psf 484.76868 psf 250 psf 0 psf Very Dense Silty Sand Slice 29 133.65 150.79808 0 psf 365.43576 psf 265.50462 psf 250 psf 0 psf Very Dense Silty Sand Slice 30 138.32388 150.92476 0 psf 101.82714 psf 73.98175 psf 250 psf 0 psf Very Dense Silty Sand Slice 31 139.99889 151.00004 0 psf 26.229034 psf 16.389719 psf 500 psf 0 psf Very Dense Silt