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REVIEWED BLD BLD2020-1033+Geotechnical_Report+3.8.2021_4.10.40_PM+2081731February 23, 2021 ES-5323.01 Mr. Leif Helleren P.O. Box 1764 Edmonds, Washington 98026 L h ons «C Earth Solutions NW LLC Geotechnical Engineering, Construction Observationjesting and Environmental Services Subject: Geotechnical Evaluation RES U 6 Johannessen Short Plat — Lot 1 10727 — 226t" Street Southwest Mar 09 2021 EDMONDS Edmonds, Washington DE EI O MFENTSERVICES DEPARTMENT Reference: City of Edmonds Plan Review Comments, BLD2020-1033, dated November 10, 2020 Findings, Conclusions, & Decisions, PLN2018-0031, dated March 19, 2020 Earth Solutions NW, LLC Geotechnical Evaluation, ES-5323, dated July 19, 2017 Liu & Associates, Inc. Geotechnical Investigation and Recommendations L&A Job No. 8A071, dated July 21, 2008 RAM Engineering, Inc. Site Plans, dated September 22, 2020 The Leren Company, Inc. Building Plans, dated September 13, 2020 Edmonds City Code Chapter 23.80 and Section 23.40.120 Dear Mr. Helleren: As requested, Earth Solutions NW, LLC (ESNW) has prepared this geotechnical addendum responding to the referenced City of Edmonds (City) plan review comments. ESNW completed additional subsurface exploration throughout the sloped area of the site as part of preparation of this addendum. This geotechnical addendum has been prepared to respond to comment 2 of the referenced plan review documents prepared by the City. Project Description The proposed project consists of construction of a new single-family residence and associated improvements. A portion of the new structure will be located in the sloped area of the site. We understand the temporary excavation for the structure will be sloped at approximately a 1 H:1 V inclination; based on our estimates, the temporary slope will nearly extend to the clearing limits in the northwest corner of the building excavation. After construction of the structure, the foundation retaining wall will be backfilled to restore the slope to a similar condition to the existing slope. 15365 N.E. 90th Street, Suite 100 0 Redmond, WA 98052 0 (425) 449-4704 9 FAX (425) 449-4711 Mr. Leif Helleren ES-5323.01 February 23, 2021 Page 2 The proposed residential structure will consist of relatively lightly loaded wood framing supported on conventional foundations. Based on our experience with similar developments, we estimate wall loads on the order of one to two kips per linear foot and slab -on -grade loading of 150 pounds per square foot (psf). If the above design assumptions are incorrect or change, ESNW should be contacted to review the recommendations provided in this addendum. Surface The subject site is located at 10727 — 226th Street Southwest in Edmonds, Washington, as illustrated on the attached Vicinity Map (Plate 1). The site consists of Lot 1 of the proposed short plat. The overall property is currently developed with a single-family residence and associated improvements located in the northwestern portion of the property; the remainder of the site consists primarily of yard areas and lightly forested land. Within and adjacent to Lot 1, there is a slope which descends to the southeast from the northwestern portion of the lot. The slope is approximately 18 to 20 feet in height and has a slope gradient of up to approximately 35 to 38 percent. The slope is vegetated with mature trees and ferns. Subsurface Conditions As part of this geotechnical evaluation, An ESNW representative observed, logged, and sampled two test pits on June 29, 2017 and three test pits on January 18, 2021, excavated at accessible locations within the proposed development area. The approximate locations of the test pits are depicted on Plate 2 (Test Pit Location Plan). Please refer to the test pit logs provided in Appendix A for a more detailed description of subsurface conditions. Representative soil samples collected at the test pit locations were analyzed in general accordance with the Unified Soil Classification System (USCS) and United States Department of Agriculture (USDA) methods and procedures. Topsoil and Fill Topsoil was observed extending to depths of approximately three to six inches below existing grades. The topsoil was characterized by dark brown color and fine organic material. Fill deposits were not encountered at the test pit locations during our fieldwork. Native Soil Underlying the topsoil, native soil conditions at the test pit locations were observed to consist primarily of poorly graded gravel with sand and poorly graded sand with and without silt (USCS: GP, SP-SM, and SP, respectively) outwash deposits. The native soil deposits were generally observed to be in a medium dense condition beginning at depths of approximately one to three feet below existing grades. Earth Solutions NW. LLC Mr. Leif Helleren February 23, 2021 Geologic Setting ES-5323.01 Page 3 The referenced geologic map indicates the project location is underlain by Vashon advance outwash (Qva). The advance outwash is characterized primarily as sand and gravel deposit. The soil conditions observed at the test pit locations are generally consistent with the geologic mapping. Groundwater Groundwater was not encountered at the test pit locations at the time of our exploration. Perched seepage, however, may be encountered during site grading activities, particularly during the winter, spring, and early summer months. It is noted that groundwater seepage rates and elevations fluctuate depending on many factors, including precipitation duration and intensity, the time of year, and soil conditions. In general, groundwater flow rates are higher during the wetter, winter months. Geological Hazards Assessment As part of this geotechnical addendum letter, the referenced chapter and section of the Edmonds City Code (ECC) was reviewed. As stated in the referenced findings, conclusions, & decisions document prepared by the City, the sloped area of the site does not classify as a landslide hazard area, but does classify as an erosion hazard area. Slope Reconnaissance During our fieldwork, we performed a visual slope reconnaissance of the sloped area of the site. The main focus of our reconnaissance was to identify signs of instability or erosion hazards along the site slopes. The typical instability indicators include features such as head scarps, tension cracks, hummocky terrain, groundwater seeps along the surface and erosion features such as gulleys and rills. During the slope reconnaissance, no signs of erosion or slope instability were observed. The slope is vegetated with mature trees and ferns. Earth Solutions NW. LLC Mr. Leif Helleren ES-5323.01 February 23, 2021 Page 4 Erosion Hazard Areas — ECC 23.80.020.A. With respect to erosion hazard areas, section 23.80.020 of the ECC defines erosion hazards as "at least those areas identified by the U.S. Department of Agriculture's Natural Resources Conservation Service as having a `moderate to severe', `severe', or `very severe' rill and inter -rill erosion hazard. Erosion hazard areas are also those areas impacted by shoreland and/or stream bank erosion. Within the city of Edmonds, erosion hazard areas include: Those areas of the city of Edmonds containing soils that may experience severe to very severe erosion hazard. This group of soils includes, but is not limited to, the following when they occur on slopes of 15 percent or greater: a. Alderwood soils (15 to 25 percent slopes); b. Alderwood/Everett series (25 to 70 percent slopes), and; c. Everett series (15 to 25 percent slopes). 2. Coastal and stream erosion areas which are subject to the impacts from lateral erosion related to moving water such as stream channel migration and shoreline retreat; 3. Any area with slopes of 15 percent or greater and impermeable soils interbedded with granular soils and springs or ground water seepage, and; 4. Areas with significant visible evidence of ground water seepage, and which also include existing landslide deposits regardless of slope." The native sand soil is generally consistent with Everett series soils. Based on the ECC definition, the areas sloped greater than 15 percent within and adjacent to the property classify as erosion hazard areas. In our opinion, the proposed construction will not increase the erosion hazard for the site or adjacent properties, provide typical Best Management Practices (BMPs), such as silt fences, covering exposed soil, and permanent landscaping, are implemented during and after construction as warranted. Mapping of Geologically Hazardous Areas — ECC 23.80.030 Review of available geologically hazardous areas mapping indicates the sloped area within and adjacent to the site is an erosion hazard area. Earth Solutions NW. LLC Mr. Leif Helleren ES-5323.01 February 23, 2021 Page 5 Special Study and Report Requirements — ECC 23.80.050 A. This geotechnical engineering study and geological hazards assessment was completed by a professional engineer licensed in the state of Washington with experience analyzing geologic hazards throughout the Puget Sound region. B. 1. The project area includes the subject site as delineated in the referenced site plans. 2. No further geologically hazardous areas are located within 200 feet of the property or will be affected by construction on the property. C. This geological hazards assessment included a field investigation and an assessment of geologic hazards. This geotechnical report has been prepared, stamped, and signed by a qualified professional. It is our opinion the level of analysis completed for this geological hazards assessment is appropriate for the scale and scope of the project and scale of the geological hazard areas present. 2. A discussion of all geologically hazardous areas on the site and any geologically hazardous areas off site potentially impacted by the proposed project is provided in this report. 3. Based on the results of our study and on -site observations, the proposed project will not decrease slope stability or pose an unreasonable threat to persons or property either on or off site. These conclusions are based on the current conditions of the slope as well as slope stability analysis of the existing and proposed conditions; results of the slope stability analysis are attached to this letter. 4. This geological hazard assessment is provided as adequate information to comply with requirements of ECC geological hazards. 5. This geotechnical report generally follows the guidelines set forth in the Washington State Department of Licensing Guidelines for Preparing Engineering Geology Reports in Washington (2006). 6. A landslide hazard minimum building setback is unnecessary due to no identified landslide hazard, and erosion hazard mitigation recommendations are provided in this report. D. ESNW has reviewed the referenced documents prepared for the property. E. The mitigation recommendations include permanent solutions, such as landscaping within the slope area in question and an engineered storm design for the property. Landscaping and vegetation along the slope should be maintained subsequent to being established during completion of the project. Earth Solutions NW. LLC Mr. Leif Helleren February 23, 2021 ES-5323.01 Page 6 F. This geological hazards assessment and geotechnical report should be reviewed as part of the overall submittal package. 1. Please refer to referenced site plans prepared by RAM Engineering, Inc. for the site plan. a. The height of the slopes and slope gradients discussed in this report have been determined using site specific topographic data. b. Springs, seeps, or other surface expressions of groundwater were not observed on or within 200 feet of the project area. c. The proposed lot is currently undeveloped, and there are currently no surface water runoff features. 2. The following is the hazard analysis: a. Vegetative cover across the landslide hazard area generally consists of large trees and ferns. b. Subsurface conditions are described in the Subsurface section of this report. c. Surface and groundwater conditions are discussed in previous sections of this report. The subject lot is undeveloped, refer to the civil plans for public and private sewage and disposal systems. d. Based on our investigation, the slope exhibits good stability which will be maintained throughout the life of the structure. e. The slopes within and adjacent to the subject site are not characterized as bluffs and we do not anticipate a retreat of the slopes to occur. f. Based on the sand soils present on the site and no indications of groundwater seepage, we would anticipate the run -out hazard of landslide debris to be confined to a distance of up to the height of slope away from the toe. If such a landslide occurred, impacts of run -out on downslope properties would likely consist of a few feet of landslide debris covering the ground adjacent to the toe of the slope. Repair of the slide would likely require cleanup of debris and engineered reconstruction of the. It should be noted, based on the results of our study, likelihood of such a landslide event occurring adjacent to the subject site is low and the proposed project will not increase the likelihood. g. ESNW completed slope stability analysis for the existing and proposed conditions, the results of which demonstrate suitable safety factors; the results of the slope stability analysis are provided as an attachment. h. It is our opinion the proposed project does not require any building site limitations. i. The native sand soil is relatively permeable and runoff potential is expected to be low. Utilization of infiltration systems is recommended for the proposed project. Earth Solutions NW. LLC Mr. Leif Helleren ES-5323.01 February 23, 2021 Page 7 3. This geotechnical engineering study was prepared by a licensed engineer. a. Geotechnical design parameters are provided within this report. b. Drainage and subdrainage recommendations are provided within this report. c. Earthwork recommendations are provided within this report. d. Recommendations for mitigation of adverse site conditions are provided within this report, as necessary. G. It is our opinion the site erosion hazard areas should be considered stable. H. Based on the results of our study, the site does not contain any seismic hazard areas. Development Standards (General Requirements) — ECC 23.80.060 Based on the results of our geological hazards assessment, the proposed project will not increase the threat of the geological hazard to adjacent properties beyond predevelopment conditions, the proposed project will not adversely impact other critical areas, the proposed project is designed so that the hazard to the project is eliminated or mitigated to a level equal to or less than predevelopment conditions, and the project is certified as safe as designed under anticipated conditions. Development Standards (Specific Hazards) — ECC 23.80.070 A. 1. No landslide hazard areas have been identified within or adjacent to the site; no building setback is necessary. 2. Based on the results of our study, it is our opinion that a buffer is not necessary for the currently proposed project. 3. The proposed project will include alteration of an erosion hazard area. The alteration will include a temporary excavation within the sloped area, temporary erosion control measures, construction of an engineered retaining wall, backfill of the retaining wall with structural fill, and establishing permanent erosion control measures, such as landscaping vegetation. Provided the recommendations in this report and subsequent geotechnical recommendations are incorporated into the design and construction of the project, the proposed alteration will not increase surface water discharge or sedimentation to adjacent properties beyond predevelopment conditions, will not decrease slope stability on adjacent properties, and such alterations will not adversely impact other critical areas. Earth Solutions NW. LLC Mr. Leif Helleren February 23, 2021 ES-5323.01 Page 8 4. a. As part of this geological hazards assessment, we assessed the current slope conditions and performed slope stability analysis. Based on our analysis, provided that our recommendations are followed, construction of the proposed addition will not reduce the current factor of safety of the current slope configuration and safety factors are above 1.5 for static and 1.2 for dynamic conditions. b. It is our opinion that the structure and improvements have been engineered in a manner which sufficiently mitigates impacts to geologically hazardous areas; ESNW should review any plan changes. c. The structures and improvements have been designed to alter a small portion of the erosion hazard area; and, it is our opinion the proposed project is reasonable and feasible from a geotechnical standpoint with respect to the erosion hazard. d. The structures and improvements have been designed to alter a small portion of the erosion hazard area; and, it is our opinion the proposed project is reasonable and feasible from a geotechnical standpoint with respect to the erosion hazard. e. The proposed development will not result in greater risk or a need for increased buffers on neighboring properties. f. A foundation retaining wall and small rockery will be constructed to reestablish and maintain the surrounding sloped topography. 5. We understand vegetation will be removed to complete the project construction and reestablished as part of permanent landscaping. 6. It is our opinion that this site should not be restricted to seasonal clearing and grading work. However, temporary erosion control measures must be implemented and maintained to minimize erosion potential. 7. We are not aware of proposed point discharges. Slope Stability Analysis ESNW completed a quantitative slope stability analysis of the existing and proposed site conditions using Morgenstern -Price methodology with GeoStudio 2021 Slope/W software. Soil strength parameters and groundwater conditions included in the analysis are representative of the competent sand soil conditions observed at the site. The slope stability analysis was completed through a representative critical cross-section extending through and beyond the proposed erosion hazard alteration area; the location of the cross-section is displayed on Plate 2 (Test Pit Location Plan). The static and seismic factors of safety (FS) for critical slip surfaces are provided below. Static FS Seismic FS Existing Condition 2.3 1.2 Proposed Condition 2.0 1.3 Earth Solutions NW. LLC Mr. Leif Helleren ES-5323.01 February 23, 2021 Page 9 The results of our analyses, as well as additional modeling parameters, are provided as an attachment. In accordance with the Edmonds City Code and utilizing USGS Seismic Design Maps, a peak horizontal ground acceleration (PGA) value of 0.52g was used for site -specific modeling. The pseudostatic coefficient used in the stability analyses was equivalent to one-half of the PGA, or 0.26g. The analysis yielded that the proposed conditions minimum FS values are overall not reduced from the existing condition values. Site Excavations Temporary site excavations over four feet in height within the site soils should be sloped at a maximum inclination of 1H:1V (Horizontal:Vertical). If temporary site excavations cannot be achieved with the above slope inclinations, temporary shoring may be necessary. ESNW should observe site excavations to confirm adequate excavation stability. Foundations Based on the results of our investigation, the proposed single-family structure can be supported on conventional spread and continuous footings bearing on undisturbed competent native soil, compacted native soil, or new structural fill. Based on the soil conditions encountered at the test sites, competent native soils suitable for support of foundations should be encountered beginning at depths of approximately one to three feet below existing grades. Where loose or unsuitable soil conditions are encountered at foundation subgrade elevations during site preparation activities, compaction of the soils to the specifications of structural fill, or overexcavation and replacement with granular structural fill will be necessary. Structural fill should consist of suitable granular soils compacted to 95 percent of Modified Proctor (ASTM D1557). Organic material exposed at foundation subgrade elevations must be removed and grades restored with structural fill. Provided the structures will be supported as described above, the following parameters can be used for design of the new foundations: • Allowable soil bearing capacity 2,500 psf • Passive earth pressure • Coefficient of friction 300 pcf (equivalent fluid) MR The passive earth pressure and coefficient of friction include an FS of 1.5. A one-third increase in the allowable soil bearing capacity can be assumed for short-term wind and seismic loading conditions. With structural loading as expected, total settlement in the range of one inch is anticipated, with differential settlement of about one-half inch. The majority of the settlements should occur during construction, as dead loads are applied. Earth Solutions NW. LLC Mr. Leif Helleren ES-5323.01 February 23, 2021 Page 10 Preliminary Retaining Wall Recommendations Retaining walls must be designed to resist earth pressures and applicable surcharge loads. The following parameters can be used for retaining wall design: • Active earth pressure (unrestrained condition) • Active earth pressure (backslope) • At -rest earth pressure (restrained condition) • At -rest earth pressure (backslope) • Traffic surcharge (passenger vehicles) • Passive earth pressure • Coefficient of friction • Seismic surcharge * Where H equals the retained height 35 pcf 50 pcf 55 pcf 70 pcf 70 psf (rectangular distribution) 300 pcf MW 8H* The passive earth pressure and coefficient of friction include an FS of 1.5. Additional surcharge loading should be included in the retaining wall design if necessary. Drainage should be provided behind retaining walls such that hydrostatic pressures do not develop. If drainage is not provided, hydrostatic pressures should be included in the wall design. Retaining walls should be backfilled with at least 18 inches of free -draining material or sheet drainage that extends along the height of the wall. The upper one foot of the wall backfill can consist of a less permeable soil, if desired. A perforated drain pipe should be placed along the base of the wall and connected to an approved discharge location. Seismic Considerations The 2015 International Building Code recognizes the American Society of Civil Engineers (ASCE) for seismic site class definitions. Based on the soil conditions encountered at the boring location, in accordance with Table 20.3-1 of the ASCE Minimum Design Loads for Buildings and Other Structures manual, Site Class D should be used for design. In our opinion, liquefaction susceptibility of the site soils is low. The absence of a shallow groundwater table condition is the primary basis for this opinion. Earth Solutions NW. LLC Mr. Leif Helleren February 23, 2021 Limitations ES-5323.01 Page 11 The recommendations and conclusions provided in this letter 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. A warranty is not expressed or implied. Variations in the soil and groundwater conditions observed at the test pit locations may exist and may not become evident until construction. ESNW should reevaluate the conclusions provided in this letter if variations are encountered. We trust this letter meets your current needs. Should you require additional information, or have questions, please call. Sincerely, EARTH SOLUTIONS NW, LLC 3/2021 Henry T. Wright, P.E. Senior Project Manager Attachments: Plate 1 — Vicinity Map Plate 2 — Test Pit Location Plan Test Pit Logs Grain Size Distribution Slope Stability Analysis Results Earth Solutions NW. LLC 41a y° ,\ bell Street r%P � ek - Edmonds Edmonds Mahn Street_ —Mahnn Street - N �� IL Dayton Street Dayton Street '\ -Ile-ay X Ma a <Maple Street Maple Street m _ Yost Park Alder Street '. ye 3 Walnut Street Walnut Street Walnut Street S //Ea//yo Q 3 - - -. f° i F as o nve -__Edmonds - Cedar Street y - E Moll D -hd I Howell Way Ln Spruce Street Dsprufe street — - — —_ y --_ - Edmonds Hemlock Way, ay `m T Pmes,e - City Park Edmonds J 215th sstee In est t Laurel street iSou `N Pine Street \\ Pine Street m Pine S[ree[ &'Pine Street 21611 street Southwest 216th Street Southwest D e F� (e 217th Street Southwest v �O\ Forsyth Lans o Fir Street.- Road `Edmonds¢ 3 Bella roola P - L yp Elm Street \ elm street _ _ P _=220th-StreetSouthwest_ . -- a � h � 1 � .. e`° 3 vim_! �;• No",Q , I( D m v n 90 Q WA 10\\ oaCane Qo KuLshan R."'V 3 P 224t h Street Southwest a Espe ❑ ��� A,yenrl�,n�n � a i as ersoocnwest z26t In � D D foe o ^ an a.4 �o 'RvGan �ar� 4 ro pro $die o ° 0 — n c--- 228YhStCeetS _ LJ- Itl � o etch Deer Drive er 5 3o� ■ Y s wA ek Edmo� 0\ x 7w'doldway _ \ j _ - - Z31st Street Southwe D °i.Ti► �� p - a e L1-c 232nd Street 5ou[hwest D - 0 bn Holly to- 3 - Io, �� 8a o o Q� Edmonds o Maple Lane _ ¢ 0 p �60 ��0 l��1 IEa �0 --HergMt z,4d ,t �rr_rr� .�rl a ` a O oo9?r �Ro d o Marro -Lane o2235th-P—Southwest 236th Street SouthwestDol t I8 School K-85choal Snoline \ P $ _ ys238th Street Southwest _ I Elementary ( - 237[h Place yrn C./ 238th Street Southwest School "81�°` y 240th Street Southwest 240th Street Southwest AO ¢West �� 4so3 WA Reference: NORTH• Snohomish County, Washington EaNWLLC Geortechnical Engineering, Construction OpenStreetMap.org bservation/Testing and Environmental Services Vicinity Map Johannessen Short Plat Edmonds, Washington Drwn. MRS Date 02/19/2021 Prol No. 5323.01 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. Checked HTW Date Feb. 2021 Plate 1 I I L----------------------------- - I I I I ---------- I I I\ I I \ 270 I ----------, TP-103 I I i TP-102 280 TP-101 — ■ — I TP-1 I _ ---TP-21------ i —■ 226TH STREET S.W. r-------- I I I I I I I I I I I I I I I I / I 1 I I I I I I I I I I LEGEND TP-101 Approximate Location of _(U a o a c' o — — ■ — ESNW Test Pit, Proj. No. o � ES-5323.01, Jan. 2021 TP_1 Approximate Location of o _ a -0 ■ — ESNW Test Pit, Proj. No. a o ES-5323, June 2017 o -0 _ �w I Subject Site L__ Existing Building Proposed Building Slope Stability Cross Section 0 30 60 120 Scale in Feet NOTE: The graphics shown on this plate are not intended for design �I�l purposes or precise scale measurements, but only to illustrate the approximate test locations relative to the approximate locations of Drwn. By M RS 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 Checked By or interpretation of the data by others. HTW NOTE: This plate may contain areas of color. ESNW cannot be Date responsible for any subsequent misinterpretation of the information 02/19/2021 resulting from black & white reproductions of this plate. Proj. No. 5323.01 Plate 2 Earth Solutions NWLLC SOIL CLASSIFICATION CHART MAJOR DIVISIONS SYMBOLS TYPICAL DESCRIPTIONS GRAPH LETTER GRAVEL AND CLEAN GRAVELS ''� I.�•� � � � A. GW WELL -GRADED GRAVELS, GRAVEL - SAND MIXTURES, LITTLE OR NO FINES GRAVELLY SOILS (LITTLE OR NO FINES) ° �° o �° o pOo p Q Q oQ GP POORLY -GRADED GRAVELS, GRAVEL - SAND MIXTURES, LITTLE OR NO FINES COARSE GRAINED SOILS MORE THAN 50% OF COARSE GRAVELS WITH FINES o Q 0 °° o ' p GM SILTY GRAVELS, GRAVEL - SAND - SILT MIXTURES FRACTION RETAINED ON NO. 4 SIEVE (APPRECIABLE AMOUNT OF FINES) �±� V CLAYEY GRAVELS, GRAVEL - SAND - CLAY MIXTURES SAND AND CLEAN SANDS SW WELL -GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO FINES MORE THAN 50% OF MATERIAL IS LARGER THAN SANDY NO. 200 SIEVE SIZE SOILS (LITTLE OR NO FINES) ::. SP POORLY -GRADED SANDS, GRAVELLY SAND, LITTLE OR NO FINES SANDS WITH FINES c•M c SILTY SANDS, SAND - SILT MIXTURES MORE THAN 50% OF COARSE FRACTION PASSING ON NO. 4 SIEVE (APPRECIABLE AMOUNT OF FINES) cC �7 CLAYEY SANDS, SAND - CLAY MIXTURES INORGANIC SILTS AND VERY FINE ML SANDS, ROCK FLOUR, SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY FINE GRAINED SOILS SILTS AND LIQUID LIMIT LESS THAN 50 CLAYS CL INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS OL ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY MORE THAN 50% OF MATERIAL IS SMALLER THAN NO. 200 SIEVE MH INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE SAND OR SILTY SOILS SIZE SILTS AND LIQUID LIMIT CLAYS GREATER THAN 50 CI I INORGANIC CLAYS OF HIGH PLASTICITY OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTS HIGHLY ORGANIC SOILS '/ ` 1/ 01/ 01/ N \„ \„ „ 0 0„ PT PEAT, HUMUS, SWAMP SOILS WITH HIGH ORGANIC CONTENTS DUAL SYMBOLS are used to indicate borderline soil classifications. The discussion in the text of this report is necessary for a proper understanding of the nature of the material presented in the attached logs. Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 PROJECT NUMBER ES-5323 DATE STARTED 6/29/17 COMPLETED 6/29/17 EXCAVATION CONTRACTOR CLE EXCAVATION METHOD LOGGED BY AZS CHECKED BY HTW NOTES Depth of Topsoil & Sod 4": soil w _ w v w ~ J TESTS _ Q O 2 QZ U) I�7 TPSL% MC = 6.6% SM MC = 3.2% MC = 3.0% Fines = 0.9% MC = 11.7% TEST PIT NUMBER TP-1 PAGE 1 OF 1 PROJECT NAME Johannessen Short Plat GROUND ELEVATION TEST PIT SIZE GROUND WATER LEVELS: AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION --- MATERIAL DESCRIPTION 0.5 Dark brown, TOPSOIL Tan silty SAND with gravel, medium dense, moist o � O O o � O o O C�o O o GP O o O � O o � O O o �o O n1 9.0 Gray poorly graded GRAVEL with sand, medium dense, damp [USDA Classification: extremely gravelly SAND] -becomes moist Test Pit terminated at 9.0 feet below existing grade. No groundwater encountered during excavation. No caving observed. Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 go Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 PROJECT NUMBER ES-5323 DATE STARTED 6/29/17 COMPLETED 6/29/17 EXCAVATION CONTRACTOR CLE EXCAVATION METHOD LOGGED BY AZS CHECKED BY HTW NOTES Depth of Topsoil & Sod 6": grass TEST PIT NUMBER TP-2 PAGE 1 OF 1 PROJECT NAME Johannessen Short Plat GROUND ELEVATION TEST PIT SIZE GROUND WATER LEVELS: AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION --- w _ ~w _ wv J TESTS 0- O MATERIAL DESCRIPTION ❑ �Z o O Q U) 0 TPSL ' ` '' 0.5 Dark brown TOPSOIL, roots Brown silty SAND with gravel, medium dense, moist - MC = 7.6% SM - MC = 2.8% 2.0 ° Gray poorly graded GRAVEL with sand, medium dense, damp Oo ° �° MC = 2.3% O� [USDA Classification: extremely gravelly SAND] 5 Fines = 0.2% GP ° �° Oo �° Oo _ 7.0 Gray poorly graded SAND, medium dense, moist - SP MC - 16.6% Fines = 0.1 % 9.0 [USDA Classification: slightly gravelly SAND] Test pit terminated at 9.0 feet below existing grade. No groundwater encountered during excavation. No caving observed Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 go Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 PROJECT NUMBER ES-5323.01 DATE STARTED 1/18/21 COMPLETED 1/18/21 EXCAVATION CONTRACTOR Client Provided EXCAVATION METHOD LOGGED BY KTK CHECKED BY HTW NOTES Depth of Topsoil & Sod 3"- 6": forest duff w }� U _ H �- L1 w m C) d ui a? ui 0 < Q Z C� U S P- SM 5 TEST PIT NUMBER TP-101 PAGE 1 OF 1 PROJECT NAME Johannessen Short Plat GROUND ELEVATION 278 ft TEST PIT SIZE GROUND WATER LEVELS: AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION --- MATERIAL DESCRIPTION 0.5 Dark brown TOPSOIL, trace roots to 5' Brown poorly graded SAND with silt, medium dense, moist Test pit terminated at 7.5 feet below existing grade. No groundwater encountered during excavation. No caving observed. 277.5 Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 go Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 PROJECT NUMBER ES-5323.01 DATE STARTED 1/18/21 COMPLETED 1/18/21 EXCAVATION CONTRACTOR Client Provided EXCAVATION METHOD LOGGED BY KTK CHECKED BY HTW NOTES Depth of Topsoil & Sod 3"- 6": forest duff TEST PIT NUMBER TP-102 PAGE 1 OF 1 PROJECT NAME Johannessen Short Plat GROUND ELEVATION 270 ft TEST PIT SIZE GROUND WATER LEVELS: AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION --- w _ wv ~w a ? _ O MATERIAL DESCRIPTION Cn < Q Z (D U) 0 TPSL '` �0.5 Dark brown TOPSOIL Brown silty SAND with gravel, medium dense, moist SM 3.0 Brown poorly graded SAND with silt and gravel, medium dense, moist 5 SP- -becomes gray, dense SM -becomes wet Test pit terminated at 7.5 feet below existing grade. No groundwater encountered during excavation. No caving observed. 269.51 Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 go Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 PROJECT NUMBER ES-5323.01 DATE STARTED 1/18/21 COMPLETED 1/18/21 EXCAVATION CONTRACTOR Client Provided EXCAVATION METHOD LOGGED BY KTK CHECKED BY HTW NOTES Depth of Topsoil & Sod 3"- 6": forest duff TEST PIT NUMBER TP-103 PAGE 1 OF 1 PROJECT NAME Johannessen Short Plat GROUND ELEVATION 288 ft TEST PIT SIZE GROUND WATER LEVELS: AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION --- w _ wv ~w a ? _ O MATERIAL DESCRIPTION Cn < Q Z (D U) 0 TPSL ' ' ' 0.5 Dark brown TOPSOIL, trace roots to 4' Brown poorly graded SAND with silt, medium dense, moist SP- -becomes gray SM 5 1 1 I Test pit terminated at 6.5 feet below existing grade. No groundwater encountered during excavation. No caving observed. 287.5 Ld 31�1 1 I INS �llil�ii iA millillin millillin llmmiiiiiiimmiiiiiii,s- lismillillismillillinm lins�ii lillin diil 1 I111 iiiiiiinm �m USDA: Gray Extremely Gravelly Sand. USCS: GP with Sand. TP-2 9.0oft. USDA: Gray Slightly Gravelly Sand. USCS: SP. 0 ■ 2/9/2021 Existing Condition, Seismic Existing Condition, Seismic Report generated using GeoStudio 2021. Copyright © 1991-2020 GEOSLOPE International Ltd. File Information File Version: 11.00 Title: Johannessen Short Plat Created By: Henry Wright Last Edited By: Henry Wright Revision Number: 7 Date: 02/09/2021 Time: 02:58:55 PM Tool Version: 11.0.0.21118 File Name: Existing Condition, Seismic.gsz Directory: C:\Users\henry.wright\Documents\SlopeW\5323.01\ Last Solved Date: 02/09/2021 Last Solved Time: 02:58:56 PM Project Settings Unit System: U.S. Customary Units Analysis Settings Existing Condition, Seismic Kind: SLOPE/W Method: Morgenstern -Price Settings Side Function Interslice force function option: Half -Sine PWP Conditions from: (none) Unit Weight of Water: 62.430189 pcf Slip Surface Direction of movement: Left to Right Use Passive Mode: No Slip Surface Option: Entry and Exit Critical slip surfaces saved: 1 Optimize Critical Slip Surface Location: No Tension Crack Option: (none) Distribution F of S Calculation Option: Constant Advanced Geometry Settings Minimum Slip Surface Depth: 3 ft Number of Slices: 30 Factor of Safety Convergence Settings Maximum Number of Iterations: 100 Tolerable difference in F of S: 0.001 Solution Settings Search Method: Root Finder file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Seismic.html 1/4 2/9/2021 Existing Condition, Seismic Materials Tolerable difference between starting and converged F of S: 3 Maximum iterations to calculate converged lambda: 20 Max Absolute Lambda: 2 Sand Model: Mohr -Coulomb Unit Weight: 120 pcf Effective Cohesion: 0 psf Effective Friction Angle: 36 ° Phi-B: 0 ° Slip Surface Entry and Exit Left Type: Range Left -Zone Left Coordinate: (2.63964, 291.6594) ft Left -Zone Right Coordinate: (27, 288.51613) ft Left -Zone Increment: 8 Right Type: Range Right -Zone Left Coordinate: (37.87117, 285.6664) ft Right -Zone Right Coordinate: (100, 268) ft Right -Zone Increment: 8 Radius Increments: 4 Slip Surface Limits Left Coordinate: (0, 292) ft Right Coordinate: (100, 268) ft Seismic Coefficients Horz Seismic Coef.: 0.26 Geometry Name: 2D Geometry Settings View: 2D Element Thickness: 1 ft Points X y Point 1 0 ft 292 ft Point 2 0 ft 250 ft Point 3 100 ft 268 ft Point 4 100 ft 250 ft Point 5 31 ft 288 ft Point 6 84 ft 270 ft file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Seismic.html 2/4 2/9/2021 Regions Existing Condition, Seismic Material Points I Area Region 1 1 Sand 1,5,6,3,4,2 1 3,081 ftZ Slip Results Slip Surfaces Analysed: 334 of 405 converged Current Slip Surface Slip Surface: 256 Factor of Safety: 1.2 Volume: 132.16976 ft3 Weight: 15,860.371 Ibf Resisting Moment: 4,700,435 Ibf•ft Activating Moment: 3,966,760.2 Ibf•ft Resisting Force: 9,710.2432 Ibf Activating Force: 8,194.9845 Ibf Slip Rank: 1 of 405 slip surfaces Exit: (83.918797, 270.02758) ft Entry: (17.864865, 289.69486) ft Radius: 462.794 ft Center: (182.59049, 722.18041) ft Slip Slices X Y pWp Frictional Cohesive Suction Base Strength Strength Strength Material Slice 1 .95946 289.28111 0 psf 19.163467 psf 0 psf 0 psf Sand ft ft Slice 2 21.148649 288.45993 0 psf 56.751076 psf 0 psf 0 psf Sand Slice 3 .337838 287.65133 0 psf 93.084302 psf 0 psf 0 psf Sand ft ft Slice 4 .527027 286.85524 0 psf 128.32384 psf 0 psf 0 psf Sand ft ft Slice 5 .716216 286.0716 0 psf 162.64992 psf 0 psf 0 psf Sand ft ft Slice 6 .905405 285.30033 0 psf 196.25743 psf 0 psf 0 psf Sand ft ft Slice 7 ft .102475 284.53868 0 psf 213.18383 psf 0 psf 0 psf Sand ft Slice 8 .307425 283.78668 0 psf 213.5248 psf 0 psf 0 psf Sand ft ft Slice 9 .512375 283.04704 0 psf 213.50852 psf 0 psf 0 psf Sand ft ft Slice 38.717325 282.31969 0 psf 213.14343 psf 0 psf 0 psf Sand 10 ft ft Slice 40.922274 281.60458 0 psf 212.40965 psf 0 psf 0 psf Sand 11 ft ft Slice 43.127224 280.90165 0 psf 211.25563 psf 0 psf 0 psf Sand 12 ft ft Slice 45.332174 280.21083 0 psf 209.59666 psf 0 psf 0 psf Sand 13 ft ft file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Seismic.html 3/4 2/9/2021 Existing Condition, Seismic Slice 47.537124 279.53208 0 psf 207.31633 psf 0 psf 0 psf Sand 14 ft ft Slice 49.742074 278.86533 0 psf 204.27149 psf 0 psf 0 psf Sand 15 ft ft Slice 51.947024 278.21053 0 psf 200.30112 psf 0 psf 0 psf Sand 16 ft ft Slice 54.151974 277.56764 0 psf 195.23852 psf 0 psf 0 psf Sand 17 ft ft Slice 56.356924 276.93659 0 psf 188.92591 psf 0 psf 0 psf Sand 18 ft ft Slice 58.561874 276.31734 0 psf 181.22975 psf 0 psf 0 psf Sand 19 ft ft Slice 60.766823 275.70983 0 psf 172.05465 psf 0 psf 0 psf Sand 20 ft ft Slice 62.971773 275.11403 0 psf 161.35393 psf 0 psf 0 psf Sand 21 ft ft Slice 65.176723 274.52988 0 psf 149.13496 psf 0 psf 0 psf Sand 22 ft ft Slice 67.381673 273.95734 0 psf 135.4584 psf 0 psf 0 psf Sand 23 ft ft Slice 69.586623 273.39636 0 psf 120.43106 psf 0 psf 0 psf Sand 24 ft ft Slice 71.791573 272.84691 0 psf 104.19356 psf 0 psf 0 psf Sand 25 ft ft Slice 73.996523 272.30893 0 psf 86.904465 psf 0 psf 0 psf Sand 26 ft ft Slice 76.201473 271.78239 0 psf 68.723416 psf 0 psf 0 psf Sand 27 ft ft Slice 78.406423 271.26724 0 psf 49.795749 psf 0 psf 0 psf Sand 28 ft ft Slice 80.611372 270.76345 0 psf 30.240828 psf 0 psf 0 psf Sand 29 ft ft Slice 82.816322 270.27099 0 psf 10.145475 psf 0 psf 0 psf Sand 30 ft ft file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Seismic.html 4/4 300 290 280 O (6 270 W NO( 250 1) 0 10 20 30 40 50 60 70 80 90 100 Distance (ft.) 2/9/2021 Existing Condition, Static Existing Condition, Static Report generated using GeoStudio 2021. Copyright © 1991-2020 GEOSLOPE International Ltd. File Information File Version: 11.00 Title: Johannessen Short Plat Created By: Henry Wright Last Edited By: Henry Wright Revision Number: 5 Date: 02/09/2021 Time: 02:52:13 PM Tool Version: 11.0.0.21118 File Name: Existing Condition.gsz Directory: C:\Users\henry.wright\Documents\SlopeW\5323.01\ Last Solved Date: 02/09/2021 Last Solved Time: 02:52:13 PM Project Settings Unit System: U.S. Customary Units Analysis Settings Existing Condition, Static Kind: SLOPE/W Method: Morgenstern -Price Settings Side Function Interslice force function option: Half -Sine PWP Conditions from: (none) Unit Weight of Water: 62.430189 pcf Slip Surface Direction of movement: Left to Right Use Passive Mode: No Slip Surface Option: Entry and Exit Critical slip surfaces saved: 1 Optimize Critical Slip Surface Location: No Tension Crack Option: (none) Distribution F of S Calculation Option: Constant Advanced Geometry Settings Minimum Slip Surface Depth: 3 ft Number of Slices: 30 Factor of Safety Convergence Settings Maximum Number of Iterations: 100 Tolerable difference in F of S: 0.001 Solution Settings Search Method: Root Finder file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Static.html 1/4 2/9/2021 Existing Condition, Static Materials Tolerable difference between starting and converged F of S: 3 Maximum iterations to calculate converged lambda: 20 Max Absolute Lambda: 2 Sand Model: Mohr -Coulomb Unit Weight: 120 pcf Effective Cohesion: 0 psf Effective Friction Angle: 36 ° Phi-B: 0 ° Slip Surface Entry and Exit Left Type: Range Left -Zone Left Coordinate: (2.63964, 291.6594) ft Left -Zone Right Coordinate: (27, 288.51613) ft Left -Zone Increment: 8 Right Type: Range Right -Zone Left Coordinate: (37.87117, 285.6664) ft Right -Zone Right Coordinate: (100, 268) ft Right -Zone Increment: 8 Radius Increments: 4 Slip Surface Limits Left Coordinate: (0, 292) ft Right Coordinate: (100, 268) ft Geometry Name: 2D Geometry Settings View: 2D Element Thickness: 1 ft Points X y Point 1 0 ft 292 ft Point 2 0 ft 250 ft Point 3 100 ft 268 ft Point 4 100 ft 250 ft Point 5 31 ft 288 ft Point 6 84 ft 270 ft Regions Material Points I Area Region 1 1 Sand 1,5,6,3,4,2 1 3,081 ft2 file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Static.html 2/4 2/9/2021 Slip Results Existing Condition, Static Slip Surfaces Analysed: 354 of 405 converged Current Slip Surface Slip Surface: 392 Factor of Safety: 2.3 Volume: 262.45359 ft' Weight: 31,494.431 Ibf Resisting Moment: 1,728,200 Ibf•ft Activating Moment: 742,502.79 Ibf•ft Resisting Force: 20,850.348 Ibf Activating Force: 8,958.2617 Ibf Slip Rank: 1 of 405 slip surfaces Exit: (83.918797, 270.02758) ft Entry: (27, 288.51613) ft Radius: 77.865739 ft Center: (77.667609, 347.64198) ft Slip Slices X Y pWp Frictional Cohesive Suction Base Strength Strength Strength Material Slice 1 28 ft 7.6877 0 psf 47.611533 psf 0 psf 0 psf Sand ft Slice 2 30 ft 6.08491 0 psf 138.30024 psf 0 psf 0 psf Sand ft Slice 3 31.944979 284.62491 0 psf 205.51372 psf 0 psf 0 psf Sand ft ft Slice 4 .834936 283.29556 0 psf 251.07843 psf 0 psf 0 psf Sand ft ft Slice 5 ft •724893 282.0476 0 psf 292.08038 psf 0 psf 0 psf Sand ft Slice 6 .61485 280.87646 0 psf 329.19788 psf 0 psf 0 psf Sand ft ft Slice 7 39 .504807 f79.77816 0 psf 362.95353 psf 0 psf 0 psf Sand ft Slice 8 41.394764 f78.74922 0 psf 393.72833 psf 0 psf 0 psf Sand ft Slice 9 ft .284721 f77.78655 0 psf 421.77219 psf 0 psf 0 psf Sand Slice 45.174678 276.88747 0 psf 447.21198 psf 0 psf 0 psf Sand 10 ft ft Slice 47.064635 276.04956 0 psf 470.05795 psf 0 psf 0 psf Sand 11 ft ft Slice 48.954592 275.2707 0 psf 490.20962 psf 0 psf 0 psf Sand 12 ft ft Slice 50.844549 274.54901 0 psf 507.46234 psf 0 psf 0 psf Sand 13 ft ft Slice 52.734506 273.88279 0 psf 521.5159 psf 0 psf 0 psf Sand 14 ft 54.624463 ft 273.27056 Slice 0 psf 531.98631 psf 0 psf 0 psf Sand 15 ft 56.51442 ft Slice 272.711 ft 0 psf 538.42215 psf 0 psf 0 psf Sand 16 ft file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Static.html 3/4 2/9/2021 Existing Condition, Static Slice 58.404377 272.20294 0 psf 540.32628 psf 0 psf 0 psf Sand 17 ft ft Slice 60.294334 271.74532 0 psf 537.18337 psf 0 psf 0 psf Sand 18 ft ft Slice 62.184291 271.33726 0 psf 528.4929 psf 0 psf 0 psf Sand 19 ft ft Slice 64.074248 270.97796 0 psf 513.80638 psf 0 psf 0 psf Sand 20 ft ft Slice 65.964205 270.66673 0 psf 492.76625 psf 0 psf 0 psf Sand 21 ft ft Slice 67.854162 270.40299 0 psf 465.14307 psf 0 psf 0 psf Sand 22 ft ft Slice 69.744119 270.18626 0 psf 430.86676 psf 0 psf 0 psf Sand 23 ft ft Slice 71.634076 270.01614 0 psf 390.04751 psf 0 psf 0 psf Sand 24 ft ft Slice 73.524034 269.89233 0 psf 342.98256 psf 0 psf 0 psf Sand 25 ft ft Slice 75.413991 269.81461 0 psf 290.14638 psf 0 psf 0 psf Sand 26 ft ft Slice 77.303948 269.78283 0 psf 232.16388 psf 0 psf 0 psf Sand 27 ft ft Slice 79.193905 269.79694 0 psf 169.76841 psf 0 psf 0 psf Sand 28 ft ft Slice 81.083862 269.85697 0 psf 103.74875 psf 0 psf 0 psf Sand 29 ft ft Slice 82.973819 269.96303 0 psf 34.890534 psf 0 psf 0 psf Sand 30 ft ft file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Existing Condition, Static.html 4/4 300 290 280 S` O (6 270 W NO( 250 L 0 ES-5323.01 Johannessen Short Plat - Lot 1 HTW 10 20 30 Existing Condition Static 2.3 • Color Name Unit Weight Effective Effective (pcq Cohesion Friction Angle (psfl (0) id 120 0 36 40 50 60 Distance (ft.) 774' 70 80 90 100 300 290 17, 280 O (6 270 W 250 0 10 20 30 40 50 60 70 80 90 100 Distance (ft.) C11 290 1-. 280 i` O M a) 270 W 260 250 L 0 ES-5323.01 Proposed Condition Johannessen Short Plat - Lot 1 Static HTW Color Name Unit Effective Effective 10 20 30 40 50 60 Distance (ft. ) Weight Cohesion Friction (pcq (psf) Angle (°) CIP Wall 150 Rockery 145 1,000 60 Sand 120 0 36 Building Surcharge 70 80 90 100 2/9/2021 Proposed Condition, Seismic Proposed Condition, Seismic Report generated using GeoStudio 2021. Copyright © 1991-2020 GEOSLOPE International Ltd. File Information File Version: 11.00 Title: Johannessen Short Plat Created By: Henry Wright Last Edited By: Henry Wright Revision Number: 12 Date: 02/09/2021 Time: 02:46:30 PM Tool Version: 11.0.0.21118 File Name: Proposed Condition.gsz Directory: C:\Users\henry.wright\Documents\SlopeW\5323.01\ Last Solved Date: 02/09/2021 Last Solved Time: 02:46:31 PM Project Settings Unit System: U.S. Customary Units Analysis Settings Proposed Condition, Seismic Kind: SLOPE/W Method: Morgenstern -Price Settings Side Function Interslice force function option: Half -Sine PWP Conditions from: (none) Unit Weight of Water: 62.430189 pcf Slip Surface Direction of movement: Left to Right Use Passive Mode: No Slip Surface Option: Entry and Exit Critical slip surfaces saved: 1 Optimize Critical Slip Surface Location: No Tension Crack Option: (none) Distribution F of S Calculation Option: Constant Advanced Geometry Settings Minimum Slip Surface Depth: 3 ft Number of Slices: 30 Factor of Safety Convergence Settings Maximum Number of Iterations: 100 Tolerable difference in F of S: 0.001 Solution Settings Search Method: Root Finder file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition - Seismic.html 1/5 2/9/2021 Proposed Condition, Seismic Materials Tolerable difference between starting and converged F of S: 3 Maximum iterations to calculate converged lambda: 20 Max Absolute Lambda: 2 Sand Model: Mohr -Coulomb Unit Weight: 120 pcf Effective Cohesion: 0 psf Effective Friction Angle: 36 ° Phi-B: 0 ° Rockery Model: Mohr -Coulomb Unit Weight: 145 pcf Effective Cohesion: 1,000 psf Effective Friction Angle: 60 ° Phi-B: 0 ° CIP Wall Model: High Strength Unit Weight: 150 pcf Slip Surface Entry and Exit Left Type: Range Left -Zone Left Coordinate: (0.87574, 291.887) ft Left -Zone Right Coordinate: (31, 288) ft Left -Zone Increment: 8 Right Type: Range Right -Zone Left Coordinate: (36.7939, 286.03226) ft Right -Zone Right Coordinate: (96, 269.5) ft Right -Zone Increment: 8 Radius Increments: 4 Slip Surface Limits Left Coordinate: (0, 292) ft Right Coordinate: (100, 269.5) ft Seismic Coefficients Horz Seismic Coef.: 0.26 Surcharge Loads Surcharge Load 1 Surcharge (Unit Weight): 250 pcf Direction: Vertical file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition - Seismic.html 2/5 2/9/2021 Coordinates Proposed Condition, Seismic X y 56 ft 270.5 ft 100 ft 270.5 ft Geometry Name: 2D Geometry Settings View: 2D Element Thickness: 1 ft Points X y Point 1 0 ft 292 ft Point 2 0 ft 250 ft Point 3 100 ft 269.5 ft Point 4 100 ft 250 ft Point 5 31 ft 288 ft Point 6 45 ft 283.90566 ft Point 7 43 ft 283.92453 ft Point 8 43 ft 280 ft Point 9 46 ft 280 ft Point 10 46 ft 281 ft Point 11 55 ft 281 ft Point 12 55 ft 268.5 ft Point 13 56 ft 281 ft Point 14 56 ft 269.5 ft Point 15 59 ft 269.5 ft Point 16 59 ft 268.5 ft Regions Material Points Area Region 1 Sand 1,5,7,8,9,10,11,12,16,15,3,4,2 2,914 ft2 Region 2 Rockery 7,6,10,9,8 10.283 ft2 Region 3 CIP Wall 11,13,14,15,16,12 15.5 ft2 Slip Results Slip Surfaces Analysed: 184 of 405 converged Current Slip Surface Slip Surface: 253 Factor of Safety: 1.3 Volume: 402.40692 ft3 Weight: 49,010.906 Ibf Resisting Moment: 1,548,812.4 Ibf•ft Activating Moment: 1,196,640.4 Ibf•ft Resisting Force: 32,759.809 Ibf file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition - Seismic.html 3/5 2/9/2021 Proposed Condition, Seismic Activating Force: 25,328.65 Ibf Slip Rank: 1 of 405 slip surfaces Exit: (68.577276, 269.5) ft Entry: (19.703403, 289.45763) ft Radius: 43.723775 ft Center: (57.317943, 311.74921) ft Slip Slices X Y pWp Frictional Cohesive Suction Base Strength Strength Strength Material Slice 1 .510302 288.19661 0 psf 51.795997 psf 0 psf 0 psf Sand ft ft Slice 2 ft .124102 285.83957 0 psf 149.55572 psf 0 psf 0 psf Sand ft Slice 3 .737902 283.77494 0 psf 231.58091 psf 0 psf 0 psf Sand ft ft Slice 4 .351701 281.94102 0 psf 299.9197 psf 0 psf 0 psf Sand ft ft Slice 5 .965501 280.29702 0 psf 357.85978 psf 0 psf 0 psf Sand ft ft Slice 6 .579301 f78.81424 0 psf 409.27084 psf 0 psf 0 psf Sand ft Slice 7 30.1931 ft 7.47163 0 psf 458.15416 psf 0 psf 0 psf Sand ft Slice 8 31.857143 276.21888 0 psf 500.92458 psf 0 psf 0 psf Sand ft ft Slice 9 .571429 f75.05004 0 psf 541.02829 psf 0 psf 0 psf Sand ft Slice 35.285714 273.99521 0 psf 588.24873 psf 0 psf 0 psf Sand 10 ft ft 37 ft f 773.04505 0 psf 643.90653 psf 0 psf 0 psf Sand 11SliCe Slice 38.714286 272.19197 0 psf 708.21226 psf 0 psf 0 psf Sand 12 ft ft Slice 40.428571 271.42981 0 psf 780.29749 psf 0 psf 0 psf Sand 13 ft ft Slice 42.142857 270.75348 0 psf 858.30405 psf 0 psf 0 psf Sand 14 ft ft 44 ft 0.11631 0 psf 1,026.7575 psf 0 psf 0 psf Sand 15SliCe ft 45.5 ft 269.65604 0 psf 1,009.5593 psf 0 psf 0 psf Sand 16SliCe ft 0 psf 1lce 46.75 ft 269.32882 0 psf 946.77973 psf 0 psf Sand ft 0 psf 18ce 48.25 ft 268.98295 0 psf 1,045.4114 psf 0 psf Sand ft Slice 49.75 ft 268.6921 0 psf 1,140.2147 psf 0 psf 0 psf Sand Sliceft 51.25 ft 268.45516 0 psf 1,228.4207 psf 0 psf 0 psf Sand 2li ft I 21Ce 52.75 ft 268.27124 0 psf 1,307.2171 psf 0 psf 0 psf Sand ft 22Ce 54.25 ft 268.13968 0 psf 1,373.8687 psf 0 psf 0 psf Sand Slice 55.5 ft 268.06611 1 0 psf 1,724.3281 psf 0 psf 0 psf Sand file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition - Seismic.html 4/5 2/9/2021 Proposed Condition, Seismic 23 ft Slice 56.75 ft 268.03556 0 psf 560.80858 psf 0 psf 0 psf Sand 2li ft 25Ce 58.25 ft 268.04181 0 psf 573.19707 psf 0 psf 0 psf Sand ft Slice 59.798106 268.10316 0 psf 548.65355 psf 0 psf 0 psf Sand 26 ft ft Slice 61.394319 268.22325 0 psf 537.92216 psf 0 psf 0 psf Sand 27 ft ft Slice 62.990532 268.40244 0 psf 514.97482 psf 0 psf 0 psf Sand 28 ft ft Slice 64.586744 268.64146 0 psf 480.43194 psf 0 psf 0 psf Sand 29 ft ft 0 psf Slice 66.182957 268.94132 0 psf 435.37775 psf 0 psf Sand 30 ft ft Slice 67.77917 269.3033 0 psf 381.31902 psf 0 psf 0 psf Sand 31 ft ft file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition - Seismic.html 5/5 300 ES-5323.01 Proposed Condition •1_3 Johannessen Short Plat - Lot 1 Seismic HTW 290 1-. 280 i` O M a) 270 W 260 250 L 0 Color Name Unit Effective Effective 10 20 30 40 50 60 Distance (ft. ) Weight Cohesion Friction (pcq (psf) Angle (°) CIP Wall 150 Rockery 145 1,000 60 Sand 120 0 36 Building Surcharge 70 80 90 100 2/9/2021 Proposed Condition, Static Proposed Condition, Static Report generated using GeoStudio 2021. Copyright © 1991-2020 GEOSLOPE International Ltd. File Information File Version: 11.00 Title: Johannessen Short Plat Created By: Henry Wright Last Edited By: Henry Wright Revision Number: 13 Date: 02/09/2021 Time: 02:44:24 PM Tool Version: 11.0.0.21118 File Name: Proposed Condition, Static.gsz Directory: C:\Users\henry.wright\Documents\SlopeW\5323.01\ Last Solved Date: 02/09/2021 Last Solved Time: 02:44:25 PM Project Settings Unit System: U.S. Customary Units Analysis Settings Proposed Condition, Static Kind: SLOPE/W Method: Morgenstern -Price Settings Side Function Interslice force function option: Half -Sine PWP Conditions from: (none) Unit Weight of Water: 62.430189 pcf Slip Surface Direction of movement: Left to Right Use Passive Mode: No Slip Surface Option: Entry and Exit Critical slip surfaces saved: 1 Optimize Critical Slip Surface Location: No Tension Crack Option: (none) Distribution F of S Calculation Option: Constant Advanced Geometry Settings Minimum Slip Surface Depth: 3 ft Number of Slices: 30 Factor of Safety Convergence Settings Maximum Number of Iterations: 100 Tolerable difference in F of S: 0.001 Solution Settings Search Method: Root Finder file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition, Static.html 1/5 2/9/2021 Proposed Condition, Static Materials Tolerable difference between starting and converged F of S: 3 Maximum iterations to calculate converged lambda: 20 Max Absolute Lambda: 2 Sand Model: Mohr -Coulomb Unit Weight: 120 pcf Effective Cohesion: 0 psf Effective Friction Angle: 36 ° Phi-B: 0 ° Rockery Model: Mohr -Coulomb Unit Weight: 145 pcf Effective Cohesion: 1,000 psf Effective Friction Angle: 60 ° Phi-B: 0 ° CIP Wall Model: High Strength Unit Weight: 150 pcf Slip Surface Entry and Exit Left Type: Range Left -Zone Left Coordinate: (0.87574, 291.887) ft Left -Zone Right Coordinate: (31, 288) ft Left -Zone Increment: 8 Right Type: Range Right -Zone Left Coordinate: (36.7939, 286.03226) ft Right -Zone Right Coordinate: (96, 269.5) ft Right -Zone Increment: 8 Radius Increments: 4 Slip Surface Limits Left Coordinate: (0, 292) ft Right Coordinate: (100, 269.5) ft Seismic Coefficients Horz Seismic Coef.: 0 Surcharge Loads Surcharge Load 1 Surcharge (Unit Weight): 250 pcf Direction: Vertical file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition, Static.html 2/5 2/9/2021 Coordinates Proposed Condition, Static X y 56 ft 270.5 ft 100 ft 270.5 ft Geometry Name: 2D Geometry Settings View: 2D Element Thickness: 1 ft Points X y Point 1 0 ft 292 ft Point 2 0 ft 250 ft Point 3 100 ft 269.5 ft Point 4 100 ft 250 ft Point 5 31 ft 288 ft Point 6 45 ft 283.90566 ft Point 7 43 ft 283.92453 ft Point 8 43 ft 280 ft Point 9 46 ft 280 ft Point 10 46 ft 281 ft Point 11 55 ft 281 ft Point 12 55 ft 268.5 ft Point 13 56 ft 281 ft Point 14 56 ft 269.5 ft Point 15 59 ft 269.5 ft Point 16 59 ft 268.5 ft Regions Material Points Area Region 1 Sand 1,5,7,8,9,10,11,12,16,15,3,4,2 2,914 ft2 Region 2 Rockery 7,6,10,9,8 10.283 ft2 Region 3 CIP Wall 11,13,14,15,16,12 15.5 ft2 Slip Results Slip Surfaces Analysed: 192 of 405 converged Current Slip Surface Slip Surface: 389 Factor of Safety: 2.0 Volume: 280.52682 ft3 Weight: 34,385.294 Ibf Resisting Moment: 765,374.85 Ibf•ft Activating Moment: 378,888.32 Ibf•ft Resisting Force: 24,144.747 Ibf file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition, Static.html 3/5 2/9/2021 Proposed Condition, Static Activating Force: 11,951.368 Ibf Slip Rank: 1 of 405 slip surfaces Exit: (68.577276, 269.5) ft Entry: (31, 288) ft Radius: 27.933071 ft Center: (57.953146, 295.33378) ft Slip Slices X y pWp Frictional Cohesive Suction Base Strength Strength Strength Material Slice 1 31.6 ft ft 6.25783 0 psf 61.680601 psf 0 psf 0 psf Sand Slice 2 32.8 ft ft 3.26515 0 psf 182.65209 psf 0 psf 0 psf Sand Slice 3 34 ft ft 1.0112 0 psf 276.21316 psf 0 psf 0 psf Sand Slice 4 35.2 ft ft 9.1635 0 psf 353.46604 psf 0 psf 0 psf Sand Slice 5 36.4 ft 277.59041 0 psf 420.51472 psf 0 psf 0 psf Sand ft Slice 6 37.6 ft ft 6.22259 0 psf 481.1683 psf 0 psf 0 psf Sand Slice 7 38.8 ft ft 5.01794 0 psf 537.98307 psf 0 psf 0 psf Sand Slice 8 40 ft 273.94857 ft 0 psf 592.74901 psf 0 psf 0 psf Sand Slice 9 41.2 ft ft 2.99489 0 psf 646.73804 psf 0 psf 0 psf Sand Slice 42.4 ft 2.14253 0 psf 700.83426 psf 0 psf 0 psf Sand 10 ft 43.5 ft 271.43772 0 psf 815.62807 psf 0 psf 0 psf Sand 11SliCe ft Sli12Ce 44.5 ft 270.86045 0 psf 885.97681 psf 0 psf 0 psf Sand ft 45.5 ft 0.33651 0 psf 836.1864 psf 0 psf 0 psf Sand 13SliCe ft Slice 46.642857 269.80264 0 psf 775.5799 psf 0 psf 0 psf Sand 14 ft ft Slice 47.928571 269.27059 0 psf 864.73265 psf 0 psf 0 psf Sand 15 ft ft Slice 49.214286 268.81152 0 psf 955.4992 psf 0 psf 0 psf Sand 16 ft ft 0 psf 1lce 50.5 ft 268.42166 0 psf 1,046.5254 psf 0 psf Sand ft 0 psf Slice 51.785714 268.09806 0 psf 1,135.8008 psf 0 psf Sand 18 ft ft Slice 53.071429 267.83835 0 psf 1,220.6383 psf 0 psf 0 psf Sand 19 ft ft Slice 54.357143 267.64073 0 psf 1,297.7246 psf 0 psf 0 psf Sand 20 ft ft 21Ce 55.5 ft 267.51317 0 psf 1,656.0179 psf 0 psf 0 psf Sand ft 22Ce 56.75 ft 267.43673 0 psf 503.4944 psf 0 psf 0 psf Sand ft Slice 58.25 ft 267.41236 0 psf 526.78703 psf 0 psf 0 psf Sand file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition, Static.html 4/5 2/9/2021 Proposed Condition, Static 23 ft Slice 59.59858 267.45566 0 psf 507.94154 psf 0 psf 0 psf Sand 24 ft ft Slice 60.795739 267.55224 0 psf 501.36338 psf 0 psf 0 psf Sand 25 ft ft Slice 61.992899 267.701 ft 0 psf 482.93751 psf 0 psf 0 psf Sand 26 ft Slice 63.190058 267.90278 0 psf 453.02279 psf 0 psf 0 psf Sand 27 ft ft Slice 64.387218 268.15878 0 psf 412.60377 psf 0 psf 0 psf Sand 28 ft ft Slice 65.584377 268.47054 0 psf 363.18608 psf 0 psf 0 psf Sand 29 ft ft 0 psf Slice 66.781537 268.84005 0 psf 306.61784 psf 0 psf Sand 30 ft ft 0 psf 244.87143 psf 0 psf Slice 67.978696 269.26976 0 psf Sand 31 ft ft file:///C:/Users/henry.wright/Documents/SlopeW/5323.01/Proposed Condition, Static.html 5/5 300 ES-5323.01 Proposed Condition •2-0 Johannessen Short Plat - Lot 1 Static HTW 290 1-. 280 i` O M a) 270 W 260 250 L 0 Color Name Unit Effective Effective 10 20 30 40 50 60 Distance (ft.) Weight Cohesion Friction (pcq (psf) Angle (°) CIP Wall 150 Rockery 145 1,000 60 Sand 120 0 36 Building Surcharge 70 80 90 100