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Home My WebLink AboutGEO2024-00083 - BLD Engineering / Geo-tech Reports - 5/16/2024 PLANNING GEOTECHNICAL REPORT RESIDENTIAL DEVELOPMENT SITE 00 SEA SPRAY LANE SHELTON, WASHINGTON PREPARED FOR DoNni,n MOON BY ALL AMERICAN GEOTECHNICAL OLYMPIA, WASHINGTON MAY 1612024 MASON COUNTY COMMUNITY SERVICES Geotechnical Report &.riding,Vlennu,g.Envluomm� 1l 1 H-11h.Con—way HeeIC, Instructions: This checklist must be submitted with a Geotechnical Report and completed, signed, and stamped by the licensed professional(s)who prepared the Geotechnical Report for review by Mason County pursuant to the Mason County Resource Ordinance. If an item is found not applicable, the report should explain the basis for the conclusion. Note: Unless specifically documented, this report does not provide compliance to the Intemational Residential Code Sections R403.1.7 for foundations on or adjacent to slopes. Section R403.1.8 for expansive soils or section 1808.7.1 of the International Building Code Section for Foundations on or adjacent to slopes. Applicant/Owner Donald Moon Parcel# 22020-23-94004 Site Address 00 Sea Spray Lane Shelton Washington (1) (a) A discussion of general geologic conditions in the vicinity of the proposed development, Located on page(s) 6 - 8 (b) A discussion of specific soil types. Located on page(s) 8 - 10 (c) A discussion of ground water conditions, Located on page(s) 10 (d) A discussion of the upslope geomorphology, Located on page(s) 10 (e) A discussion of the location of upland waterbodies and wetlands, Located on page(s) 10 (f) A discussion of history of landslide activity in the vicinity, as available in the referenced maps and records. Located on page(s) 10 (2) A site plan which identifies the important development and geologic features. Located on Map(s) Figure 2 Pages 11 & 28 (3) Locations and logs of exploratory holes or probes. Located on Map(s) Figure 2 Pages 11 & 28 (4) The area of the proposed development, the boundaries of the hazard, and associated buffers and setbacks shall be delineated (top, both sides, and toe)on a geologic map of the site. Located on Map(s) Figure 2 Pages 11 & 28 (5) A minimum of one cross section at a scale which adequately depicts the subsurface profile, and which incorporates the details of proposed grade changes. Located on Map(s) Figure 2 Page 2, 25, 26, & 28 (6) A description and results of slope stability analyses performed for both static and seismic loading conditions. Analysis should examine worst case failures. The analysis should include the Simplified Bishop's Method of Circles. The minimum static safety factor is 1.5,the minimum seismic safety factor is 1.1, and the quasi-static analysis coefficients should be a value of 0.15. Located on page(s) 11 - 13 (7) (a) Appropriate restrictions on placement of drainage features, Rev. February 2018 Located on page(s 13 (b) Appropriate restrictions on placement of septic drain fields, Located on page(s) 13 (c) Appropriate restrictions on placement of compacted fills and footings, Located on page(s) 13 - 14 (d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other slopes. Located on page(s) 14 (e) Recommended setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes. Located on page(s) 14 (8) Recommendations for the preparation of a detailed clearing and grading plan which specifically identifies vegetation to be removed, a schedule for vegetation removal and replanting, and the method of vegetation removal. Located on page(s) 15 (9) Recommendations for the preparation of a detailed temporary erosion control plan which identifies the specific mitigating measures to be implemented during construction to protect the slope from erosion, landslides and harmful construction methods. Located on page(s) 15 (10) An analysis of both on-site and off-site impacts of the proposed development. Located on page(s) 15 (11) Specifications of final development conditions such as, vegetative management, drainage, erosion control, and buffer widths. Located on page(s) 16 (12) Recommendations for the preparation of structural mitigation or details of other proposed mitigation. Located on page(s) 16 (13) A site map drawn to scale showing the property boundaries, scale, north arrow, and the location and nature of existing and proposed development on the site. Located on Map(s) 16 11 Curts D Cushman hereby certify under penalty of perjury that I am a civil engineer licensed in the State of Washington with specialized knowledge of geotechnical/geological engineering or a geologist or engineering geologist licen estate of Washington with special knowledge of the local conditions. I also certify that the -ci Wasf� .� fo Geotechnical Report, dated May 16, 2024 and entitled Reesidential Development Site 00 Sea Spray Lane Shelton,Wahington meets all the requirements of the Mason County Resource Ordinance, Fn �Geolcyist/� ��z y Geologically Hazardous Areas Section, is complete and true, that the 9 assessment demonstrates conclusively that the risks posed by the landslide hazard can be mitigated through the included geotechnical [Curtis Dean Cushman design recommendations, and that all hazards are mitigated in such a (Signature and Stamp) manner as to prevent harm to property and public health and safety. Page 2 of 2 Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report. ALL AMERICAN GEOTECHNICAL CONTACT INFORMATION PREPARER INFORMATION AAG PROJECT NUMBER: AAG24-054 CONTACT: CURTIS D.CUSHMAN ADDRESS: 8947 BUTTONWOOD LANE NE OLYMPIA,WASHINGTON 98516 TELEPHONE: (360)491-5155 CELL/TEST: (360)481-6677 EMAIL ADDRESS: CURTIS.CUSHMAN@COMCAST.NET CLIENT INFORMATION CLIENT: DONALD MOON TELEPHONE: (360)491-8475 BILLING ADDRESS: DONALD MOON 490143RD LANE SE LACEY,WA 98503 SITE ADDRESS: 00 SEA SPRAY LANE SHELTON,WASHINGTON EMAIL DONALDMOON123456(a)GMAIL.COM PARCEL NUMBER 22020-23-94004 GPS LOCATION: 47.206 -122.971 dd AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 2 Phone#: (360)491-5155 Cell#: (360)481-6677 EI2I( G1.,O,I t'cII\1( I . SCOPE OF UNDERSTANDING DONALD MOON 490143RD LANE SE LACEY,WA 98503 RE: GEOTECHNICAL REPORT PROPOSED RESIDENCE 00 SEA SPRAY LANE SHELTON,WASHINGTON E 1/2 W 1/2 GOVT LOT I EX LOT:D OF SP 42882 47.206 -122.971 (DD) PARCEL: 22020-23-94004 MAY 16,2024 Dear Mr. Moon: Mr. Donald Moon (client) hired All American Geotechnical, Inc. (AAG) in April, 2024 to create a geotechnical report for the above residential property in Mason County,Washington. The following is the report written to comply with the Mason County Requirements in the Mason County Code -Critical areas in accordance with the Submittal Checklistfor a Geotechnical Report for the above property southwest of Shelton in Mason County, Washington. The site is planned to be developed with a single-family residence. This report will demonstrate the area planned for the residence is suitably in compliance with Factors of Safety for a Landslide Hazard Area. As per client contact,we did a relevant site visit and a search of public documents. A copy of this report will be provided to the client by PDF. Landslide hazards will be noted and analyzed in text. Other geotechnical information is likewise included. We appreciate this opportunity to be of service to you and we look forward to working with you in the future. If you have any questions concerning the above items, the procedures used, or if we can be of any further assistance please call us at the phone number listed below. Respectfully Submitted, o Wa'Sh/ ALL AMERICAN GEOTECHNICAL,INC. w �9 eering Geo. ist 2439 V � Go Curtis D. Cushman, L.G., L.E.G. Curtis Dean Cu Senior Engineering Geologist AAG24-054 8947 Buttonwood Lane NE,Olympia, WA 98516 3 Phone#: (360)491-5155 Cell #: (360)481-6677 ALL AMERICAN GEOTECHNICAL TABLE OF CONTENTS SCOPE OF UNDERSTANDING 3 INTRODUCTION 6 1) SITE CONDITIONS 6 SURFACE CONDITIONS 6 A) SITE GEOLOGY 7 B) SOIL 8 C) GROUND WATER CONDITIONS 10 D) UPSLOPE GEOMORPHOLOGY 10 E) UPSLOPE WATERBODIES AND WETLANDS 10 F) LANDSLIDE ACTIVITY 10 2) SITE PLAN 11 3) EXPLORATORY HOLES OR PROBES 11 4) PROPOSED DEVELOPMENT 11 5) CROSS SECTION 11 6) SLOPE STABILTY ANALYSIS 11 SEISMIC LIQUEFACTION HAZARD 12 GEOSEISMIC SETTING 12 LATERAL EARTH PRESSURES 13 7)RESTRICTIONS 13 A)PLACEMENT OF DRAINAGE FEATURES 13 B)PLACEMENT OF SEPTIC DRAIN FIELDS 13 C)PLACEMENT OF COMPACTED FILLS AND FOOTINGS 13 RECOMMENDATIONS FOR SITE PREPARATION 13 RECOMMENDATIONS FOR STRUCTURAL FILL 14 D)BUFFERS 14 E)SETBACKS 14 8)CLEARING AND GRADING PLAN 15 9)EROSION CONTROL PLAN 15 10)ON AND OFFSITE IMPACTS 15 11)FINAL DEVELOPMENT CONDITIONS 16 12)STRUCTURAL MITIGATION 16 13 SITE PLAN 16 CONCLUSIONS AND RECOMMENDATIONS 16 PROVISIONS 16 GENERAL 16 CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS 17 READ THESE PROVISIONS CLOSELY 17 AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 4 Phone#: (360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL REFERENCES 18 MAPS 18 PUBLICATIONS 18 WEBSITES 18 APPENDIX 19 LIDAR IMAGERY 20 NEIGHBORING WELL LOG-- 101 E SEA SPRAY LANE 21 NEIGHBORING WELL LOG-- 115 E SEA SPRAY LANE 22 ASCE7-16 SEISMIC DESIGN SPECIFICATIONS 23 SLOPE MODELS 25 STATIC MODEL A-A' 25 DYNAMIC MODEL A-A' 26 FIGURES 27 FIGURE I VICINITY MAP 27 FIGURE 2. SITE PLAN 28 FIGURE 3. EROSION CONTROL NOTES 29 AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 5 Phone#: (360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL INTRODUCTION This report summarizes the results of our geotechnical study of the parcel herein described. The proposed building site is on a shotgun parcel of 2.27 acres in area long to the north-south. Development will be south of Sea Spray Lane and above a steep bluff descending south to Hammersley Inlet. The parcel is currently undeveloped. Access would be off Sea Spray Lane which is off E Agate Road via E Hammersley Reach Road. E Agate Road turns from SR-6 northeast of Shelton, Washington. In general, the parcel is on a slope descending gently to the west. However, at its southern end, the slope swings to the southwest and then finally descends nearly 100 feet abruptly to the south, terminating at the water's edge. The slope descending to the water is well over 40%and 10 feet in height. The elevation of the parcel is highest at over 120 feet north of Sea Spray with the lowest at mean sea level at the southern end of the parcel. The proposed residence will be around the 100-foot contour. Our understanding of the project is based on information from the client. This geotechnical report and the checklist for Mason County involves the following: 1. A review of the available geologic,hydrogeological and geotechnical data for the site area. 2. A detailed geologic reconnaissance of the site area and surrounding vicinity. 3. Investigation and identification of shallow subsurface conditions at the site by characterizing the exposed soil, sampling, and reviewing published well logs. 4. Comparison of the site to published geologic maps,previous field investigations,and open file reports. Inspection of aerial photographs to determine the geomorphology of the site. 5. Evaluation of the landslide, erosion, and seismic hazards at the site per the Mason County Critical Areas Ordinance regulations. 6. Slope modelling. As the slope south of the parcel exceeds 40%and is greater in height than 10 feet and is within 300 feet of the proposed building site, this is considered a Landslide Hazard Area (LHA) Therefore, Mason County requires that a geotechnical report be prepared in accordance with the Mason County Ordinance; 8.52 Resource Ordinance. 8.52.140 Geologically hazardous areas. 1) SITE CONDITIONS SURFACE CONDITIONS The proposed location for the residential development is on a relatively flat terrace of glacial till above Hammersley Inlet. The immediate area is one of typical ridge-and-valley fluted terrain carved by continental glaciation and, in this area,surfaced by lodgment till. Curtis D Cushman, L.E.G. of AAG conducted a site visit on April 17, 2024. The client was on site. The purpose of a site visit is to physically observe the property and adjacent properties in order to identify any recognized geologic conditions. Visual observations were documented. AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 6 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL The parcel is mostly forested except for the bluff which is mixed with brush. The trees are straight and vertical showing little evidence of movement. The development area is constrained by the sight-lines between neighboring residences. It is nearly level and the underlying geology is straightforward (see below). A) SITE GEOLOGY The site is mapped as Qgt— Fashon Stade till Geologic Unit Symbol: Qgt Geologic Unit Age: Pleistocene Geologic Unit Name: Vashon Stade till Publication Source: WGS Publication Number: OFR 2003-23 Quadrangle Name: Squaxin Island Feature Link: WGS I OFR 2003-23 1 Squaxin Island I Qgt Unit Description: Unsorted and highly compacted mixture of clay, silt, sand, and gravel deposited directly by glacier ice;gray where fresh and light yellowish brown where oxidized; very low permeability; ...cobbles and boulders commonly faceted and(or) striated; ranges in thickness from wispy, discontinuous layers less than I in. thick to more than 30 ft thick; ...typically, weakly developed modern soil has formed on the cap of loose gravel, but the underlying till is unweathered... Age: Pleistocene Lithology: continental glacial till Age-Lithology: Pleistocene continental glacial till The above description is taken verbatim from the Geologic Map of the Squaxin Island 7.5-minute Quadrangle, Mason and Thurston Counties, Washington; 2003;Logan,Robert L. and others; Washington Division of Geology and Earth Resources Open File Report 2003-23. The geology at the client parcel has been interpreted as a thicker blanket of Qgt than is usually mapped. This is because the Squaxin Island Quad does not show any underlying deposits in this area. These are commonly Qps and Qpf sedimentary materials seen elsewhere which are firm pre-Vashon deposits. In addition, water wells indicate finer deposits than anticipated, following site observations, which indicate the area may have a layer of lacustrine deposits nearby, similar to the post-till Qgof deposits seen to the east. This is not an important consideration for this slope stability modeling, but should be borne in mind when excavating; finer grained sediments, including possible clays or elastic silts may be encountered. It is also to be noted that the width and location of the band of Qls—Landslide deposits is incorrect. This mapping should be restricted to the bluff and not to the terrace above it. A A G 24-0�4 8947 Buttonwood Lane NE,Olympia,WA 98516 7 Phone#: (360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL What was seen in the field was gravelly sand with some silt. The deposits seen on site are likely SP Poorly graded gravelly sand. The glacial deposits are firm and suitable for construction. Clay, again, may be present, but it is unlikely. There are no nearby folds or faults. The major mountain building is well to the west along the Olympic Mountains thrust faults and associated structures. Nearby water wells have columns that are varied in makeup, one in the appendix shows fine-grained deposits. This indicates the presence of lakes in the area following the end of the latest glacial stade. In no well was there a definite contact found between the mapped Vashon till and underlying,earlier,deposits. The closest major fault is the Tacoma fault zone that is near Allyn, Washington over 13 miles to the north- northeast of the client parcel. Seismic acceleration is important in modelling the slope stability as the Puget Sound area is in an active tectonic zone and although this fault does not pose an immediate hazard to the proposed building project, low levels of seismic activity are not uncommon and there is always the possibility of a major shock. In the case of a Cascadia event,the site is mapped on the Washington Geologic Information Portal as in a zone with a potential MMI of 7, Very Strong In the case of a Tacoma event, the site is mapped on the Washington Geologic Information Portal as in a zone with a potential MMI of 6, Strong. In the case of a Seattle event, the site is mapped on the Washington Geologic Information Portal as in a zone with a potential MMI of 7, Very Strong. The development zone is mapped on the Coastal Zona Atlas as a Stable slope. The bluff is mapped as an Unstable slope. This is in keeping with it being mapped as a feeder bluff that is allowed to be eroded at its base by wave and tidal weathering to provide sediments into the marine environment of South Puget Sound. The land will be eroded back, but this will take many years as the slopes appear resistant and well- vegetated. It is mostly within the Shoreline Environmental Designation of"Residential." The DNR 2007 Hazard Zone is Low at the development site and is High along the bluff. The DNR 2009 Landforms shows a somewhat larger bluff area as being High. The DNR 2010 Landslides mapping shows failure along the bluff, but is, again, in error, being too far to the north. This error, by the way, is likely due to scaling up from the large-scale Quad map to the smaller-scales seen on the Information Portal. The building area is within a shoreline conservancy area that is not defined any further. This mapping appears to be incorrect, being too far north. B) SOIL The soil in the areas of the proposed development is described by the USDA Web Soil Survey as: AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 8 Phone#:(360)491-5155 Cell#: (360)481-6677 ALL AMERICAN GEOTECHNICAL So Sinclair shotty loam,5 to 15 percent slopes Map Unit Setting • National map unit symbol. 2hn7 • Elevation: 0 to 300 feet • Mean annual precipitation: 25 to 50 inches • Mean annual air temperature: 50 degrees F • Frost free period: 200 days Description of Sinclair Setting • Landform: Till plains Typical profile • HI - 0 to 11 inches: gravelly loam • H2- 11 to 35 inches: very gravelly loam • H3 -35 to 60 inches: gravelly sandy loam Properties and qualities • Slope: 5 to 15 percent • Depth to restrictive feature: 28 to 42 inches to densic material • Drainage class: Moderately well drained • Capacity of the most limiting layer to transmit water(Ksat): Very low to moderately low(0.00 to 0.06 in/hr) • Depth to water table: About 18 to 30 inches • Frequency offlooding.None • Frequency of ponding.None • Available water supply, 0 to 60 inches: Low(about 3.7 inches) This soil was what was seen on site. The bluff to the south is likely the following due to being steeper than 15 percent: Rl—Rough broken land Map Unit Setting • National map unit symbol: 2hmr • Elevation: 0 to 710 feet • Mean annual precipitation: 50 inches • Mean annual air temperature: 50 degrees F • Frost free period.• 180 days • Farmland classification:Not prime farmland AAG24-054 8947 Buttonwood Lane NE,Olympia, WA 98516 9 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL Description of Rough Broken Land Typical profile • HI - 0 to 4 inches: gravelly loam • H2 - 4 to 43 inches: very gravelly loam • H3 - 43 to 60 inches: very gravelly sandy loam Properties and qualities • Slope: 45 to 90 percent • Depth to restrictive feature: 20 to 72 inches to densic material • Drainage class: Well drained • Capacity of the most limiting layer to transmit water(Ksat): Moderately high to high(0.57 to 1.98 in/hr) • Depth to water table: More than 80 inches • Frequency offlooding:None • Frequency of ponding.None • Available water supply, 0 to 60 inches: Low(about 3.2 inches) The soil is similar to the Sinclair and implies similar soil formation, but the soil on the bluff is likely younger. C) GROUNDWATER CONDITIONS There is no evidence of flowing water. There was no evidence of active surface erosion. Natural drainage is toward the inlet. D) UPSLOPE GEOMORPHOLOGY The client parcel is on a low ridge that culminates at 215-feet in elevation over 4,600 feet to the north- northeast of the client development site. The intervening terrain is irregular near the client parcel but is more regular away from it as the slope rises gently to the north-northeast. This rise poses no hazard to the client parcel. E) UPSLOPE WATERBODIES AND WETLANDS There are no upland water bodies. There are no wetlands on the parcel. There are none mapped along the shore. There are no stream buffers on the site. F) LANDSLIDE ACTIVITY The bluff is mapped (somewhat erratically) as a landslide area. The criterion for this description is not known. It appears to be an erosional bluff,retreating slowly due to wave and tidal undercutting. The bluff appears relatively stable and, being well-vegetated and being comprised of an obdurate material, the rate of retreat is apparently low. AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 10 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL 2) SITE PLAN Please see Figure 2 in the Appendix. 3) EXPLORATORY HOLES OR PROBES The site was cut into the geologic deposits and the column is exposed alongside the road descending to the south. Hand samples were examined on-site. 4) PROPOSED DEVELOPMENT This will be a single-family residence. 5) CROSS SECTION A cross-section is in the Appendix. It is along line A-A'. 6) SLOPE STABILTY ANALYSIS The Slope Stability Analysis is as follows following the Mason County Code of Ordinances of 2021: 8.52.140 (E)(5) (d) A description and results of slope stability analyses performed for both static and seismic loading conditions. Analysis should examine worst case failures. The analysis should include the Simplified Bishop's Method of Circles. The minimum static safety factor is 1.5, the minimum seismic safety factor is 1.1 and the quasi-static analysis coefficients should be a value of 0.15. Slope stability was modeled using the GALENA 6.1 program in both static and dynamic conditions (ca= 0.15). "Static" condition refers to an"as is" state of a given slope. "Dynamic"puts seismic acceleration into the model for earthquake conditions. The factor for ground acceleration (ca) is set at 0.15 by Mason County. The surface soil was field classified as a SP Poorly graded gravelly sand. These units are consistent with the description of Qgt deposits. The site was modeled with a single layer. The possible water table was included in the model. Parameters used for the subsurface material are presented in the following table. Table 1. Modeling Parameters for Subsurface Material Geolo c Unit L nit «eight Cohesion Phi Angle Qgt -Vashon Stade glacial till 113 1100 ;S AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 11 Phone#: (360)491-5155 Cell#: (360)481-6677 ALL AMERICAN GEOTECHNICAL Factors of safety were determined using the Bishop (semi-circular) method. Under static conditions, the slopes did not show susceptibility to deep-seated failure that would cause damage to the existing development. See Appendix for model output and cross-sections. Under dynamic loading(Ca=0.15),the computations demonstrated that the site has a safe FoS. The following are the Factors of Safety (FoS) attained for the sections with respect to their current topographical representation. General information for the slope profiles and the initial positions for analysis is presented in the following table. Table 2. Initial Positions,Variance, and Findings Anah sis Load?cross Analysis Earthquake Slope to I Initial Positions(lnals sis Range) Co❑ficurarions Factor of Number Building Envelopel Ilpe Force iBuilding. Lo��er L-t er Radius Auahzed Safety Cross-Section A. _ _ Analysis 1 1500#172-213' IStatic 0.0 Below I 40(30) 192.5(41) 220_(100) 125,001 I1.51____ � ---- Analysis 2 11500#172-2Y 13' !Dyna❑is 0.150 g_ 40(30) 192.5(41) 320(100) 125,001 11.1�--- The values input were selected to be as conservative as possible so the FoS are possibly higher. The graphic output of these data is presented in the Appendix, pages 25-26. SEISMIC LIQUEFACTION HAZARD The Liquefaction Susceptibility Map of Mason County, Washington by Palmer, Magsino, Poelstra, Bilderback, Folger, and Niggemann (September 2004) maps the site area as having a Very Low liquefaction potential. The Site Class Map of Mason County, Washington by Palmer,Magsino, Bilderback, Poelstra,Folger, and Niggemann(September 2004)maps the area as site Class C. Site class C is a very dense soil and soft rock (nehrp classification). GEOSEISMIC SETTING According to the Seismic Zone Map of the United States (Figure 1613.3.1(1)) contained in the 2018 International Building Code (IBC), the project site is located where the maximum spectral response acceleration is greater than 65 percent of gravity(g). We recommend following seismic factors for design purposes. • Site Class: C (very dense soil/soft rock) • Spectral response acceleration, short period(Srls): 1.498 g(Fa= 1.2) • Spectral response acceleration, 1-second period(SMi): 0.551 g(Fv= 1.449) • Peak Ground Acceleration 0.671 g AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 12 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL LATERAL EARTH PRESSURES Lateral loads may be resisted by friction on the bases of footings and floor slabs and as passive pressure on the sides of footings. An allowable coefficient of friction of 0.40 may be used to calculate friction between the concrete and the underlying native soil. We recommend the following be used to determine the lateral earth pressures considering the onsite SP: • � (soil friction angle) 38 degrees • Ko(at rest earth pressure coefficient) 0.384 • Ka(active earth pressure coefficient) 0.238 • Kp(passive earth pressure coefficient) 4.20 • y(soil unit weight) 113 pcf 7)RESTRICTIONS A)PLACEMENT OF DRAINAGE FEATURES The following notes are general and may not be applicable in part to this property. All ground surfaces, pavements and sidewalks should be sloped away from the proposed residence and any associated structures. Surface water runoff should be controlled by a system of curbs, berms,drainage swales,and/or catch basins and directed onto splash blocks at least 5 feet from the footings,then dispersed overland flow onto lawn or plantings. We recommend that conventional roof drains be installed. Footing drains shall be installed for the proposed structure. The roof drain should not be connected to the footing drain. For footing drains,the drain invert should be below the bottom of the footing. Drainage may also be done by capturing the drain water then directing it by tightline to a dispersion facility at an adequate and approved location, such as a natural drainage or a beach. This technique is feasible,but the drop to the beach would cause difficulties in dispersal to avoid extra erosion. Drainage should be such that there is no flow onto or over the steep slopes to the south. B)PLACEMENT OF SEPTIC DRAIN FIELDS The drain field is located as mapped on Figure 2. The drainfields will be outside the LHA. Domestic water is from an on-site well. C)PLACEMENT OF COMPACTED FILLS AND FOOTINGS RECOMMENDATIONS FOR SITE PREPARATION There is little geotechnical site preparation to be noted. The building footprint for possible construction is outside the 50-foot vegetation buffer and aligns with the neighbors' eaves. Removal of juvenile and opportunistic trees will be required for this parcel. AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 13 Phone#: (360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL All deleterious material will then be removed and sub-soils reached for the footings for the construction of slab and/or footings. Any material that is excavated may be stockpiled and later used for erosion control and/or landscaping. Surficial material unsuitable for these tasks should be removed from the project site. No foundation elements shall be constructed on"untested"fill material. If demonstrated to be acceptable, the sand/gravel sedimentary material on site may be suitable for re-use as structural fill. Where placement of fill material is required, the exposed subgrade areas should be compacted to a firm and unyielding surface prior to placement of any fill. Over-excavation in any building area should be backfilled with structural fill, compacted to the density requirements described in the "Structural Fill" section of this report. RECOMMENDATIONS FOR STRUCTURAL FILL All fill material should be placed as structural fill. In general, the structural fill should be placed in horizontal lifts of 8 inches to allow adequate and uniform compaction of each lift. Fill should be compacted to at least 95 percent of MDD (maximum dry density as determined in accordance with ASTM D-1557)to grade. The final appropriate lift thickness will depend on the fill characteristics and compaction equipment used. Material placed for structural fill should be free of debris, organic matter,trash,and cobbles greater than 6 inches in diameter. The moisture content of the fill material should be adjusted as necessary for proper compaction. Onsite soils may be considered for use as structural fill only if industry standards are satisfied. Fill material requirements are found on page 9-26 to 9-30 of the WSDOT Standard Specifications 2010. In general, a native soil (sand, silt, and gravel) encountered on a site must have less than 10 percent fines (material passing the US No. 200 sieve)to be suitable for use as structural fill. Footing design for this material will be by the Engineer of Record. D)BUFFERS The construction area is outside the 50-foot vegetation buffer. It will be located along the neighbor eave lines. The slopes are such that erosion should be considered as a factor but, with proper control, not a limiting factor. The LHA shall not be disturbed. E)SETBACKS The geotechnical setback is seen on Figure 2, page 28. AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 14 Phone#: (360)491-5155 Cell#: (360)481-6677 ALL AwRICAN GEOTECHNICAL 8)CLEARING AND GRADING PLAN The site is undeveloped outside of an access road that will be upgraded. Clearing will be for some trees and lower-story vegetation. Clearing may be done by commonly approved standards. Grading will be limited. All job site safety issues and precautions are the responsibility of the contractor providing services and/or work. 9) EROSION CONTROL PLAN It is our opinion that the potential erosion hazard of the site is not a limiting factor for the proposed developments. The slope at the site is shallow and will be kept that way. A dangerous discharge of water is unlikely. Simple erosion control methods will reduce or eliminate any potential erosion risk. Trees and understory growth on the steep slopes will not be disturbed. Revegetation as needed should occur immediately following construction. With adequate vegetation, the erosion risk is lessened. No hazard trees appear to be present but may be removed,if identified,anywhere outside the 50-foot vegetation buffer. The possibility of down-slope contamination is unlikely if proper control methods are employed. A silt fence shall be installed as shown on Figures 2 and 3 and other control methods, such as swales and baled straw are practical. No re-contouring of the site will occur. Surface drainage should be directed away from all slope faces. Straw,hay, or jute matting shall be used to cover the exposed soils until permanent vegetation is established. All slopes should be seeded as soon as practical to facilitate the development of a vegetative cover, or otherwise protected. Surface water should be captured and directed off-parcel. A revegetation plan should not be required. When residential plantings or any plantings on the periphery of the residential area and the slopes are planned, native species should be considered as the primary vegetation in areas away from lawn and ornamental plantings. Shallow rooted species, such as grass, should be planted closer than 10 feet from underground drainages. Densely rooted evergreen shrubs are preferable than tree species on slopes greater than 15%gradient. Tall trees may become unstable in wet soils under high wind conditions. In general,the steep sides of the bluff should be left in a natural condition unless erosion or sloughing eventually pose a hazard to the residence. 10) ON AND OFFSITE IMPACTS There should be no notable on- or offsite impacts if the project is completed according to the recommendations of this report and in accordance with all regulations and to the high standards and practices of the building contractor. AAG24-054 8947 Buttonwood Lane NE,Olympia, WA 98516 15 Phone#: (360)491-5155 Cell#:(360)481-6677 ALL AMEwAN GEOTECHNICAL 11)FINAL DEVELOPMENT CONDITIONS Final development will rely on the location of the residence needing to be properly footed on competent geologic deposits with adequate setback from the LHA. All final conditions will follow the design by the Engineer of Record and compliance with all regulatory agencies. If this and the above recommendations are followed, final development conditions may be achieved. 12) STRUCTURAL MITIGATION There is no structural remediation to be done. 13 SITE PLAN Please see Figure 2. CONCLUSIONS AND RECOMMENDATIONS Based on the results of the site reconnaissance, subsurface observations, and our experience in the area, it is our opinion that the proposed development site on the client property is suitable for a residential development. The location of the residence as proposed complies with the Factors of Safety for the county code. The erosion hazard is manageable, and drainage should not pose a great problem. For erosion control,we recommend a silt fence or other erosion control measures noted above followed by revegetation. The retreat of the bluff from its current place is inevitable. This is likely not going to affect the residence location for the foreseeable future. PROVISIONS GENERAL We have prepared this report for the exclusive use of Don Moon and his authorized agents for development of this property in Mason County, Washington. Site inspections, research, and mapping have culminated in this report. This report is intended to meet the requirements of the Mason County Code. This report does not specify setbacks for: line-of-sight setbacks, FWHCA setbacks, eagle tree setbacks, wetland setbacks,or property line setbacks. Within the limitations of scope,schedule and budget,our services have been executed in accordance with generally accepted practices in the field of geotechnical engineering in this area at the time this report was prepared. No warranty or other conditions,expressed or implied,should be understood. Clients and property owners must understand that,while a slope may be found to have an acceptable Factor of Safety related to deep-seated mass wasting, surficial failure and landslides can and do occur on steep slopes. The property owners should monitor the stability of their property following construction. Moreover, acceptable Factors of Safety do not guarantee there cannot be failures. It is the responsibility of the property owners to understand that there are always risks in building on or near steeply sloped areas. AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 16 Phone#: (360)491-5155 Cell#: (360)481-6677 ALL AMERICAN GEOTECHNICAL CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS Our geotechnical recommendations are not intended to direct the contractor's procedures, methods, schedule or management of the work site. The contractor is solely responsible for job site safety and for managing construction operations to minimize risks to onsite personnel and to adjacent properties. READ THESE PROVISIONS CLOSELY Some clients, design professionals, and contractors may not recognize that the geoscience practices (geotechnical engineering or geology) are far less exact than other engineering and natural science disciplines. This lack of understanding can create unrealistic expectations that could lead to disappointments,claims and disputes.All American Geotechnical includes these explanatory"limitations" provisions in our reports to help reduce such risks. AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 17 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL REFERENCES MAPS DeLorme 3-D TopoQuads(2002),Source Data USGS,Yarmouth,Maine. Palmer, Magsino, Poelstra, Bilderback, Folger, and Niggemann (September 2004), The Liquefaction Susceptibility Map of Mason County, Washington, published by Washington State Department of Natural Resources. Palmer, Magsino, Bilderback, Poelstra, Folger, and Niggemann (September 2004), The Site Class Map of Mason County, Washington,published by Washington State Department of Natural Resources. Rogers,A.M.,Walsh,T.J.,Kockelman,W.J.,and Priest,G.R.(1996),Map showing known or suspectedfaults with quaternary displacement in the Pacific Northwest,published by U.S.Geological Survey OFR 91-441-0,Plate 1,scale 1:2,000,000. PUBLICATIONS ASTM International(2005),Annual Book of Standards 2015, Section 4, Volume 4.08,published by ASTM International,West Conshohocken,Pennsylvania. Kollmorgen Instruments Corporation(1994),Munsell Soil Color Charts(1994 Revised Edition),published by Macbeth Division of Kollmorgen Instruments Corporation,New Windsor,New York. Ness,Fowler,Parvin(1960),The Soil Survey of Mason County, Washington, USDA Soil Conservation Service,in cooperation with the United States Department of Agriculture, and Washington Agricultural Experimental Station, and the Soils Conservation Service. Parks, Neal, Koloski, Laprade, Molinari, Butler, and Lorentson (November 2006), Guidelines for Preparing Engineering Geology Reports in Washington, published by Washington State Geologist Licensing Board,Olympia,Washington. WEBSITES (as online USDA WSS, WA State Geologic Information Portal,Mason County GIS,Dept of Ecology,etc.) Mason County Government Information Services (http://www.co.mason.wa.us) Mason County Codes,Ordinances,and Regulations (http://www.co.mason.wa.us/code) Puget Sound Lidar Consortium (http://pugetsoundlidar.ess.washington.edu/lidardata/index.httnl) United States Department of Agriculture Natural Resource Conservation Service (http://soildatamart.nres.usda.gov) Washington Administrative Code (http://apps.leg.wa.gov/waco Washington Department of Ecology (http://apps.ecy.wa.gov/welllog) (https://fortress.wa.gov/ecy/coastalatlas/viewer.htm) AAG24-054 8947 Buttonwood Lane NE,Olympia, WA 98516 18 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL APPENDIX LiDAR Imagery Neighboring Well Logs ASCE7-16 Seismic Design Specifications Slope Models Figure 1. Vicinity Map Figure 2. Site Plan Figure 3.Erosion Control Notes. AAG24-054 8947 Buttonwood Lane NE, Olympia, WA 98516 19 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL LiDAR IMAGERY A. W "T•_ �. 1 D 0 1, c a F c W � 10 G 7 � 7 Q � N FF b E m � c w c 0 f m d d O y Oy t a 3 0 5 `o V m E E 0 � w w C9 - - O 000.0000 _ • ss Z AAG24-054 8947 Buttonwood Lane NE, Olympia, WA 98516 20 Phone#: (360)491-5155 Cell #: (360)481-6677 ALL AMERICAN GEOTECHNICAL NEIGHBORING WELL LOG--101 E SEA SPRAY LANE Fit F ORIG a FIRST COPY-DEPT OF ECOLOGY WATER WELL REPORT START CARD NO W1,21144 SECOND COPY-OWNER THIRD COPY-DRILLER STATE OF WASHNGTON UNrOUE WEIL ID SKS-220 WATER RIGHT PERMIT NO N!A (1)OWNER NAME DAN TURNER ADDRESS P.O.BOX 2227 SHELTON WA 93594 a LOCATION OF WELL County MASON NW 1t4 SW 114 SEC 20 TWp 20N R 2W 128)STREET ADDRESS OF WELL(orneamst address) 101 E.SEASPRAY LANE. PARCEL 220202194003 1 (3)PROPOSED USE DOMESTIO I (10)WELL LOG OR DECOMMISSIONING PROCEDURE DESCRIPTION (4)TYPE OF WORK NEW WELL I METHOD. ROTARY 1 1 MATERIAL BROWN SILTY FINE TO MED SAND 0 44 (S)DIMENSIONS Domater d leeli { rUiel GREY SILT,SOME FINE TO MED SAND,GRAVEL,Ct AY � 44 � 56 Drilled 76 liver Depth of co� cleted we: 72 n I GREY SILT.SOME GRAVEL,FINE TO MED SAND.yV e. I 59 1 0 1 GREY SILTY FINE TO COARSE SAND,GRAVEL.W.B I 61 I 72 I GREY SILTY CLAY 1 72 1 76 I I ;6)CONSTRUCTION DETAILS I I 1 Cose10 maid. 6" Dom From .i R to 67 ft Welded Dam From n to If 1 I I I I Liew Dam From C to n l I 1 Threaded 1 I I I 1 I 1 1 PorloraWns Yes ❑ No r I I 1 aY Type of perforalor used I 1 I Size of perforabons in by in I j perforasons dote ft to in.I I I perlcratons t(om I-. to „I R E C E V E D , perforaeons from h W et.i I 1 CCi L N18 I I Screens Yes 0 No ❑ 1 I 1 Maredaceuds Name. JOHNSON ; WA State Dapartment 'w Tvpe STAINLESS Model No I 1 I �yf Dom 6'TEtSiot sure 20from 670It b 720 E I Of ECOIUyyI(SWRO� Iz� Doin Slot sae from ft to f I 1 1 I 1 I I I F r I I I u Grli'm packed Yes ❑ No .7 See of 0re.++s I I I i By Gravel packed from n to 1 1 I I 1 I I Surface seal Yes 'i— No To Vnat depU17 1{ rt I 1 Matenal used n seal BENTONTTE CHIPS 1 I 1 Did any stray contain unusable wales Yes_ No o I I 3 Type of water? Depth of Strata n l I 1 Mathod of soa mg strata off I I 1 O 1 I I Z I I (7)PUMP ki—ewtivKi ham. I I Type H P 1 1 I i I 1 v I I I W ,S (6)WATER LEVELS Sunau eler above mean sin NvW C I I Stave lava) 64 below,top of wall Date 061,21:1 a I 1 I Artesian presswe Ibs Per sq n Date 1 I I i A1te►ton pressure is controlled by I I 1 I 1 8 t I � (D)WELL TESTS PUMP test ms0l? Byritwm I Wed Started 0.5722/ta Completed. 0S43riB h. Yi.q Mi. wro, a M..e..n.�.. •1 r.q Pit—•.0 It 4..rtori.n.. •is WELL CONSTRUCTOR CERTIFICATION! Y.q a.D.ie will a imnv..i.1i, n,. 1 Constructed arid/of accept responsibility for Construction of Recovery day 1 this well.and rts compliance with all Washington wet construction Tvrie Alt LO Time Wtr Lvl Time 'Mr LN i standards. Materials used and the information raported above are true to my best knovdedge and belief I IName RICHARDSON WELL DRILLING COMPANY INC. Day of lest (Address P.O.BOX 44427 TACOMA•WA SS444 Bailer test qv—win s a...d— A. his i ✓ Arlest a 0avmm stem set at 72 I1 for / M I(Sipn _ Lt No 24!? Arteuon Lbw OaUmm Date I Temperature of water Was chemical analysis made? No IContrwWs Rogistration No RICHAMP22100 DATE {r4rt{ AAG24-054 8947 Buttonwood Lane NE,Olympia, WA 98516 21 Phone#: (360)491-5155 Cell#: (360)481-6677 ALL AMERICAN GEOTECHNICAL NEIGHBORING WELL LOG--115 E SEA SPRAY LANE 0 CL WATER WELL REPORT Or/giasl L 1'eapy-Eeatep.I"copy-orate,.rr tap,-dAlkr CURRENT iri'�i o c ri Notice of l■tent No. Construction/Decommission/"z"in circle) ® Construction Unique Eco!ngy Well ID Tag No.APKW w Decommission ORIGINAL INSTALLI TION Wtutt Right Permit No. O Notice o Intent Number YaQJW C PROPOSEO USE: 0 Domestic p Intdsatra! ❑ Memicrpsl Property Owner Nature CAMP13EL.TOM G SANDRA 0 ❑ MsA."r ❑ I.r ton 0 Teu Well ❑Otler Well Street Address SEA SPRAY LN C TYPE OF W ORK: Owmr's number of well(if nrm thaw Carl 0 ®New+ell p p U ❑R«.drttoad Afe" yt Bored ❑ M,vr. Cit}' LIQZ{ County�-4� p tkepered ❑t�bk ® Rotary ❑ Jetted Location 2&1;4.1!4 ,m(I:4 Six iss Twn 2Q R 2 E DIMENSIONS: Daarcrtaf rtR�in:hrs,dnikd] Qn «\ >_ D thofc :reed-eH 8. 0 CONSTRUCTION DETAILS Lat/Loog ww-t r C Cuteg 0 Welded §" Uam aura 4 d to�n (a,t,r Still Lat Deg _ Min_Sec 1MaJkd: 0 L.uer mstaltcd= Ihtn rrom—r.to _n REQUIRED) Long Deg_ Min Sec _ ❑Threaded Uam 1 ro.�_R m _R CONSTRUCTION OR DECOMMLSSION PROCEDCRE A., Perforanoaa: 0 Yes 0 No Faruma Describe by cukr.chuxter.um of aukrui and structure,said tte lend and s- Type of perforator toed_ matve of the"n"liat�ea;h strums Peter. ed..it atus lust Cee envy fix x ewh change 0 ofmfor"aon (USE ADDtn0NAL SHEETS IF NECESSARY.) SIZE of pelts—+by—in and eo of reefs_from_P.re_ MATERIAL FROM TO C _ Scram: co Yes ❑ No ® K-ia t .rii,_' - PIPE STICK UP 0 1 r3 Miusita we*'a Nacre "NSON BROWN SAND.GRAVEL,CLAY 1 35 T)ve SSW Model Yo TELES GRAY SAND,CLAY GRAVEL WET 35 53 f f Duo,¢Stot sue gg Iram In It to In n. GRAY SILT 53 57 Dmm Sla sea from M1 o rt DARK GRAY FINE SAND 57 62 GravetTlrer parted 0 Yes 0 do Sue of gn.rtesaed_ DARK GRAY SAND.GRAVEL,SOME 62 78 +�,a Materuh placed tn;rn n to It CLAY.SEAMS OF WATER 62 78 _>% Sarfare seal: ®Yes ❑No To hv'"p O jLn GRAY CLAY,SILT 78 97 C maic+w w;ed costar SENTONITE GRAY BROWN SAND,SILT,CLAY, 97 102 Dd any sw a cattalo amrsabk ❑ Nei ® No WATER 97 102 1)re el.are^_ Depth of neon__ GRAY SAND,SOME GRAVEL. SEAM 102 131 OF WATER 1 131 Medod of scaling straw Or_ GRAY SAND.GRAVEL.WATER 13131 139 �— PUMP:Atawfxturer'a Nacre_ O r HP._ z WATERLEVELS: lrtbsmfwx ekwtwn abo.r ttttum sea ksel�l y Sulk keel'fq R Delve.sop of well Datt J0AUfr(,4.. -_-- 0 Arttsun prtssv _lbs per sduare—h Dar Anesun.metucoatorkdby. cap.ealmetc) -- C" N'[LI.TFSTS:Dnwdowa is arnoum+atn Inel K bweRd below smile kssl 0 was a ps-rp test rw.hs❑ Yes ❑No If yes.Dy wltor' P.P 0 Yield._bat'mia-itl_n dra+do.a alt"_hn LL Yieldeel/aria s.it%—n drawdorRanee hn w Yess, nl.'men.,th—n.d.a.de+n aft, hot -.- 0 R-~,y dam firer eaLeu m coo rAtw p+mp nu-ed^i—tc•fr,,J rarer—d f a wtfl eop IC,wtrrlew) I-Y.7)IIIL•9"ton C Ttme Water Iswl Toe Wale*Ie•et Ir water Intl E — — — — — R Doe of�artiaikr kst2QPt;men.rsh aQfl draw dawn afkrlM -"�-__ CL t7J Airua pt;min raD urns scrar,_M1for_Ms Anrao-now t P m Dar_ Start Date 2LAVQZ Completed Date Trmperatsne of+ater_Was a c",csil a-Nys"—del ❑Yes ❑No Tax Parcel`slo. I- WELL CONSTRUCTION CERTIFICATION: I eonstrwe d anilor accept responsibility for consuWton of tlus well,and to compliance with all Washmg:cm well cons ruction suridatds. Materials used and the information reported above are true to my best knowledge and belief. ®Driller❑Engtstoet❑Trainee Driller os uaince Li rise No 2219 Drilling Company'NICHOLSON DRILLING INC \arse its.t,b.f..rl SI;LLIVA\,JO y Address PO BOX 123 Dnikr'I:n irrcr/Tmtnee Stigriature City,State•Zip PORT ORCHARD•WA, 9b166 IF TRAINEE Dtilla's Lrceme No Contractor's Drilkr's Si turf: Registration No NICHODI1371k.1 Date t IA ECY OJO�1.20(Rev)OS) Ecobo its as Eywl Orpsetssney Enplo)w AAG24-054 8947 Buttonwood Lane NE,Olympia, WA 98516 22 Phone#: (360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL ASCE7-16 SEISMIC DESIGN SPECIFICATIONS 411 C Hazards by Location Search Information :an Coordinates: 47.206,-122.57' EI•vattort: t�3 n ,r tar Sl► Timsafamp: 2024-05-16T20 Gr 28.rO 7 .n ttemrd Type: Seism c Re hence Document:ASCE7-16 �t wrrinp Risk c III I� �' {. Klap dot X.::5 ar ylo Pe7crt a reap errer sit class: c MCBR Horizontal Response Spectrum Design Horizontal Response Spectrum sa(9) sa(8) 1.50 ',QO t,OD 0.60 C SQ 0,<n 0,20 C.00 0.00 0 5 'C 15 porter!is) 0 5 .0 15 Period(s) Basic Parameters Name Valus Description SS 1.496 MCER ground moben fpenad=0.2sj S. C,551 EdCLR ground motion(penod-t,Os) sm, 1.797 Sno-tnoddied spectral screlerator,vak:o SW 0.799 Site-modified spectral accelerstar raLe Styr 1.198 Numeric seismic design value a:0,2s SA SDI 0a32 Numenc seismic design value a.1,0s SA -Additional Information Name Value Description SDC D Se sn-c dealyn catngary F, 1.2 S.e amplitcaco-Paaor at 0.25 F. 1,.49 S-e amplifcator Paccar at I.:)s C R5 V.UC4 Coeflic*w.o'-sk(0,2e) CR• 0.8P2 :oeftiew oF,*k(1.0s1 AAG24-054 8947 Buttonwood Lane NE, Olympia, WA 98516 23 Phone#: (360)491-5155 Cell #: (360)481-6677 ALL AMERICAN GEOTECHNICAL ASCE7-16 Seismic Design Specifications continued PGA 0.641 DACE;peak ground acceleration FPGA 1.2 Ste ampldcato^-fa:tor at PGA PGA#J 0.769 S:e modifec peak ground acceleratcn T, 16 Long-penod transit on pencd(s; SsRT 1.498 Probab4stc risk-targeted ground motion(0.2s) SsUH 1.657 Factored u�fottn ward spectral accolorabo-(2%vovab lty of exceedance in 50 years) SsD 1,5 FacCored determ nisb:accelerator value(0.2s) S I RT 0.551 Prooab I st c nsk.:argeted ground mo5on(1.0s) S1UH 0.625 Fac-orod urrfortrntrazaro spectral acceletabo-(2`d o obab Ily of exco¢Canco in 50 years) SID 0.787 Fay..aeddeletmrxstr.accelerator value(1.0s) F'GAd 0.616 Fncrored cetermnistr.accelerator value(PGA) Tho rosutfa kxAcatod horn 00 NOT rolloct any sfato or focal amor dirronts to fho valims or any dohnooWn Tinos mado during fho bWd)ng codo adopt,on process.Users should cnn/irm any oufpuf obla.'red from this fool with the lxa.'Authon/y Having g Junsd,ction before proceeding w.dh design AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 24 Phone#: (360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL SLOPE MODELS STATIC MODFI.A-A' c >yQ y I O'ic�i dr � � y E g o t I C � Lu Q � 4� AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 25 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL DYNAMIC MODEL A-A' 3Ny_� 1 G V = cc /T � fY N � V h y E y 0Q i i I } } M } I } } } } a } S } N } } Q } } p O w )O J V �_._. Q S E a� u AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 26 Phone#:(360)491-5155 Cell#:(360)481-6677 ALL AMERICAN GEOTECHNICAL FIGURES FIGURE 1 VICINITY MAP 123'W".0,kN O.-MV51,Vv i22157,601 W L V X, 'q 0 J C&MA r 14 INLET 10— V94 J, jj M N 7- 2 i'l:• r CII&I ac,w vw AAG24-054 8947 Buttonwood Lane NE,Olympia,WA 98516 27 Phone#:(360)491-5155 Cell#:(360)481-6677 D g "a � m a .c � E n p C) O m Notes: o T' This is not a survey. This �'rf map is a presentation of I a z: information from county, a= o. N 3 state,and/or federal T agencies,client provided information,and onsite �C observations.7. C�7 N r = r9 O r, ti � O S� Site Soil C: 7 So--Sinclair Shotty loam, 5 to 15 percent slope. l„=' 1 � 1 , > R Site Geology , 1 3 � Qgt--Vashon glacial till i Qls--Quaternary landsli s CO i i I i i 1 � i 1 I _ i i 1 , 1 � 1 1 =\ ' 1 m i ` 0. Z c Pn+paud N �' lct' w / y _ A L--— LIM Qls 10 }nl�t 00 N FILTER FABRIC MATERIAL 80•WIDE ROLLS USE STAPLES OR WIRE RING TO ATTACH FABRIC TO WIRE 27X27X14 GAUGE WIRE FABRIC OR EQUIVALENT GENERAL EROSION CONTROL NOTES: r4r 1. EROSION CONTROL MEASURES SHALL BE IN PLACE PRIOR TO THE BEGINNING OF CONSTRUCTION.THE PROJECT ENGINEER AND THE COUNTY 5'ff \ SURFACE ,a\\ SHALL INSPECT AND APPROVE THE INSTALLATION OF 1/2 INCH MINIMUM DIAMETER STEEL ROD EROSION CONTROL MEASURES PRIOR TO BEGINNING CONSTRUCTION. (STRAP)CLAMPED SECURELY TO PIPE 2' •, -,---- 2.EROSION CONTROL MEASURES ARE NOT LIMITED TO THE ITEMS 6•MAx ON THIS PLAN.THE CONTRACTOR IS RESPONSIBLE FOR THE CORRUGATED TIGHTLINE 4 INCH /! INSTALLATION AND MAINTAI NANCE OF ALL EROSION CONTROL MEASURES. MINIMUM,6 INCH SUGGESTED NO SILTATION OF EXISTING OR PROPOSED DRAINAGE FACILITIES SHALL BE ALLOWED.CARE SHALL BE TAKEN TO PREVENT MIGRATION ^' M/N/illL 2x4•w000 POSTS,STANDARD OR BURY BOTTOM OF FILTER OF SILTS TO OFF SITE PROPERTIES. Ic+;-�: ".-, Sp4f70 BETTER OR EQUALALTERNATE: MATERIAL IN 8-2-TRENCH ';; i ^? '�.r' .:. AQ/ F-. STEEL FENCE POSTS 3.THE CONTRACTOR SHALL MAKE DAILY SURVEILLANCE OF ALL EROSION CONTROL MEASURES AND MAKE ANY NECESSARY REPAIRS OR ADDITIONS 111 ^'"TL:A}ti%_,•'. ':.:.:V'e'�:Y'.ra,.... TO THE EROSION CONTROL MEASURES.THE CONTRACTOR SHALL PROVIDE y� ' ADDITIONAL EROSION CONTROL MEASURES AS DETERMINED NECESSARY *`:' b •ri; °L w'+'F',a., By THE COUNTY INSPECTOR AND/OR THE PROJECT ENGINEER.FAILURE ?zr•p JY r4*1 �4ti r'Z tea`.{.•:�._ FILTER FABRIC 8• TO COMPLY WITH ALL LOCAL AND STATE EROSION CONTROL '•: 'Pti.'. tA/:'.?" REQUIREMENTS THE C MAY RESULT IN AND/OR PENALTIES BEING LEVIED 'r' YY r-�r''.,s •i.`•'' .':'i•>5�;, , FABRIC GAUGE WIRE k' '4h• - AGAINSTTHECONTRACTORAND/OR PROJECT OWNER. '�. c�.��p-.aA'yv:+�.;".••-w,x.��'.1 ar4.:;ji�5ipb- FABRIC OR EQUIVALENT 4.DURING THE WET SEASON NOVEMBER TO MARCH ALL DISTURBED SOILS ^.•�.-4+' ?�-''s`�;`?�"yS�aaC�:" GROUND SURFACE 5 ( ) " ""•A•. j��"'H`'�" -l+F:� SHALL BE STABILIZED WITHIN 48 HOURS AFTER STOP OF WORK.EROSION CONTROL MEASURES SHALL INCLUDE,BUr NOT BE LIMITED TO, �?'('�`��±n�!•rt"�=rr.,"„A-";u 5�•f '++�.`y,/.• PROVIDE 314•-112•WASHED COVERING GRAVEL BACKFlLL IN TRENCH THE EFFECTED AREA INCLUDING SPOIL PILES WITH 'v�'1.-' .Srti.'.4"'�•`�' v''ti w!?- '++'"�" 1Y AND ON BOTH SIDES OF FILTER PLASTIC SHEETING,STRAW MATTING.JUTE MATTING,STRAW MULCH, •`'•'E>r .*tiJ ' FENCE FABRIC ON THE SURFACE 6'MIN ORWOOSWHEAT.SEEDI GO THE DISTURBED AREAS SHALL TAKEPLACE ` TIGHTLINE ANCHORED WITH TWO, MC WCOD POSTS 5.ALL SEEDED OR SODDED AREAS SHALL BE CHECKED REGULARLY 3 FOOT REBAR LENGTHS OR BOLTS. ALT.STEEL FENCE POSTS TO MAKE SURE VEGETATIVE COVERAGE IS COMLETE.AREAS SHALL BE REPAIRED,RESEEDED,AND FERTILIZED AS REQUIRED. FILTER FABRIC FENCE NOTES: 1.FIE ER FABRIC SHALL BE PURCHASED IN A CONTINUOUS ROLL CUT TO 6.TRACKING OF SOIL OFFSITE WILL NOT BE ALLOWED.IF ANY SOIL IS THE LENGTH OF THE BARRIER TO AVOID USE OF JOINTS.WHEN JOINTS TRACKED ONTO A COUNTY STREET,IT SHALL BE REMOVED BY THE END ARE NECESSARY,FILTER CLOTH SHALL BE SPLICED TOGETHER ONLY AT OF THAT WORKING DAY.ANY FURTHER TRACKING OF MUD WILL THEN A SUPPORT POST WITH A MINIMUM 64NCH OVERLAP AND SECURELY BE PREVENTED BY SWEEPING OR WASHING OF THE VEHICLES TIRES FASTENED AT BOTH ENDS TO THE POST. BEFORE DRIVING ON A COUNTY STREET. 2.POSTS SHALL BE SPACED A MAXIMUM OF 6 FEET APART AND DRIVEN 7.NO MORE THAN 500 LF OF TRENCH ON A DOWNSLOPE OF MORE THAN 5 SECURELY INTO THE GROUND(MINIMUM OF 30INCHES). PERCENT SHALL BE OPENED AT ONE TIME. 3.A TRENCH SHALL BE EXCAVATED APPROXIMATELY 81NCHES WIDE AND 12 JJFL-AREINCHES DEEP ALONG THE UNE OF POSTS AND UPSLOPE FROM THE BARRIER. B.E%CAVATED MATERIAL SHALL BE PLACED ON THE UPHILL SIDE OF TRENCHES. END SECTION 9.TRENCH DE WATERING DEVICES SHALL BE DISCHARGED IN A MANNER THAT WILL QUARRY SPALLSLI4.WHEN BT FENCENDARD S ALL BE FASTS ED SECURELYBRIC IS TO,A WIRE MESH OR ENERGYOF THE OSTSUINGH BEFASTENEDSESTAPLV TOT EAST IIOPESIDE NOTADVERSELV AFFECT FLOWING STREAMS.DRAINAGE SYSTEMS OR ..,;�.t�" +fi+_, •-,:r�T`_�n;;a^e.Ah ED THE POSTS USING HOG VY-DUTY THE ERE SHALL AT X END INTO OFFSITE PROPERTIES. DISPERSION DEVICE .r;C:, �Saria 4W ti.Sy.J,�v;l :•:ti�T�,)'t'•-v.:j�•t•L•'+ LONG,TIE WIRER OR HOG RINGS.THE WIRE SHALL EXTEND INTO THE TRENCH A MINIMUM OF OINCHES AND SHALL NOT EXTEND MORE THAN 36 10.ALL STORM SEWER INLETS RECEIVING RUNOFF FROM THE PROJECT DURING INCHES ABOVE THE ORIGINAL GROUND SURFACE. CONSTRUCTION SHALL BE PROTECTED SO THAT SEDIMENT-LADEN WATER GRASS-LINED$WALE SHOULD BE A s.THE STANDARD STRENGTH FILTER FABRIC SHALL BE STAPLED OR WIRED WILL BE FILTERED BEFORE ENTERING THE CONVEYANCE SYSTEM. MINIMUM ONE FOOT WIDE AT THE TO THE FENCE AND 20INCHES OF FABRIC SHALL BE EXTENDED 11.ALL OFFSITE CATCH BASINS IMMEDIATELY ADJACENT TO THE SITE BOTTOM AND ONE FOOT DEEP WITH INTO THE TRENCH.THE FABRIC SHALL NOT EXTEND MORE THAN 36 SHALL BE PROTECTED FROM SILTATION. A MAXIMUM SLOPE OF 5 PERCENT. INCHES ABOVE THE ORIGINAL GROUND SURFACE.FILTER FABRIC SHALL NOT BE STAPLED TO THE EXISTING TREES. MINIMUM 4 FEET 12.ALL DISTURBED AREAS SHALL BE SEEDED OR SODDED UPON COMPLETION LEVEL SECTION 6.WHEN EXTRASTRENGTH FILTER FABRIC AND CLOSER POST SPACING IS OF WORK.THE CONTRACTOR SHALL BE RESPONSIBLE TO ENSURE THAT USED,THE WIRE MESH SUPPORT FENCE MAP BE ELIMINATED,IN SUCH COMPLETE COVERAGE OF THE DISTURBED AREAS IS PROVIDED S THAT A CASE,THE FILTER FABRIC IS STAPLED OR WIRED DIRECTLY TO THE GROWTH OF THE VEGETATION IS ESTABLISHED. GEOTEXTILE FABRIC POSTS WITH ALL OTHER PROVISIONS OR ABOVE NOTES APPLYING. 7.FRTER FABRIC FENCES SHALL NOT BE REMOVED BEFORE THE UPSLOPE 13.CATCH BASINS SHALL TRAP SEDIMENT OR FILTER FABRIC MUST BE AREA HAS BEEN PERMANENTLY STABILIZED. PLACED UNDER GRATE UNTIL VEGETATION IS ESTABUSHED. 8.FILTER FABRIC FENCES SHALL BE INSPECTED IMMEDIATELY AFTER EACH RAINFALL AND AT LEAST DAILY DURING PROLONGED RAINFALL ANY REQUIRED REPAIRS SHALL BE MADE IMMEDIATELY. All American Geotechnical,Inc. Drawn g 22020-23-94004 Figure Y� Erosion Control Notes Permit Number: Parcel Number: 3 8947 Buttonwood Lane NE BWJ 5/16/24 Proposed Home Olympia,Washington 98516 Revisions: Applicant Name: Donald Moon 111 E Sea Spray Lane Page Shelton,Washington PP Site Address: 29