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GEO2010-00003 COM2010-00005 - COM Engineering / Geo-Tech Reports - 2/16/2010
GEOENGINEERS 1101 South Fawcett Avenue,Suite 200 Tacoma,Washington 98402 253.383.4940 February 16,2010 MSGS Architects 510 South Capitol Way Olympia,Washington 98501 Attention:Garner Miller Subject: Addendum Geotechnical Engineering Services Olympia Federal Savings Building Replacement Belfair,Washington File No. 11536-002-05 INTRODUCTION AND BACKGROUND This addendum presents additional information regarding site geologic and slope conditions for the referenced project. This information was requested by Mason County because of presence of an existing slope near the north property corner. We previously presented the results of our geotechnical engineering services in a report dated September 10, 2009. We understand Olympia Federal Savings will construct a new bank branch at the subject site, which is located at 24081 NE State Route 3 in Belfair. An existing building will be demolished and replaced with a new,single-story structure with approximately the same footprint. Other existing improvements at the site include asphalt concrete paved parking and landscape areas. On site infiltration of stormwater using pervious pavement or drainage swales is under consideration. SCOPE The purpose of our supplemental services for this project is to perform additional site reconnaissance and assessment of the site slopes in general accordance with the requirements of the Mason County Resource Ordinance Chapter 17.01.100 Landslide Hazard Areas. SITE RECONNAISSANCE Site surface and subsurface conditions are described in our September 10, 2009 report. We visited the site on February 15, 2010 to specifically observe and assess the slope near the north property corner. Based on topographic contours shown on Figure 2 and our field observations,the steeper portion of this slope is about 9 feet high. Hand inclinometer measurements indicate the slope is inclined at between 50 and 75 percent. The upper portion of this slope appears to be existing fill. We observed 18-to 24-inch- diameter cedar trees on and near the slope on the adjacent properties. We did not observe indicators of MSGS Architects February 16,2010 Page 2 slope instability such as tension cracks,nor did we observe seepage in the vicinity of the slope at the time of our reconnaissance. DISCUSSION AND CONCLUSIONS Based on our prior investigation and supplemental reconnaissance it is our opinion the slope near the north property corner does not meet the criteria for a landslide hazard area. It is our further opinion that the potential for landslide activity at the site as a result of the proposed improvements is low. In our opinion,a geotechnical report meeting the requirements of the Mason County Resource Ordinance is not necessary to further evaluate site conditions and the proposed development. A copy of the Submittal Checklist for Mason County Resource Ordinance geotechnical reports is attached. LIMITATIONS We have prepared this addendum for the exclusive use of MSGS Architects and their authorized agents for the Olympia Federal Savings Building Replacement project located in Belfair,Washington. Our services were provided to evaluate certain geologic risks for a planned structure to be located on sloping property. Our recommendations are intended to maintain the overall stability of the site and to reduce the potential for future property damage related to earth movements, drainage or erosion. However, all construction on slopes involves risk, only part of which can be mitigated through qualified engineering and construction practices. Favorable performance of structures in the near term does not imply a certainty of long-term performance, especially under conditions of adverse weather or seismic activity. 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,express or implied,should be understood. Please refer to the appendix in our report dated September 10, 2009 titled "Report Limitations and Guidelines for Use"for additional information pertaining to use of this addendum. We appreciate the opportunity to be of service to you on this project. Please call if you have any questions regarding the contents of this addendum. �{ "Wa� Yours very truly, GeoEngineers, Inc. �1/l /"J/' fV4 /� .isyiYatreri:lt3 Gt'OIO�s;'>y 2s840 Garry H.Squires, PE,LG,LEG Principal d GHs:tt �AR2Y SQlRE TACO:\11\11536002\05\Flnals\1153600205RJlddeMum.docx �— Disclaimer.Any electronic form,facsimile or hard copy of the original document(email,text,table,and/or figure),if provided,and any attachments are only a copy of the original document.The original document is stored by Geoftneem Inc,and will serve as the official document of record. Attachment: Masson County Department os Community Development Checklist GEOENGINEERS REPORT GEOTECHNICAL ENGINEERING SERVICES OLYMPIA FEDERAL SAVINGS 24081 NE STATE ROUTE 3 BELFAIR,WASHINGTON SEPTEMBER 10, 2009 FOR MSGS ARCHITECTS GMENGINEERS File No. 11536-002-05 Geotechnical Engineering Services File No. 11536-002-05 September 10, 2009 Prepared for: MSGS Architects 510 South Capitol Way Olympia,Washington 98501 Attention: Garner Miller Prepared by: GeoEngineers, Inc. 1101 South Fawcett Avenue, Suite 200 Tacoma,Washington 98402 (253) 383-4940 GeoEngineers, Inc. Mackenzie J. Hanks, EIT �R� N.S Geotechnical Engineer �P Q� WA / 0 9 25824 Garry H. Squires, PE, LG, LEG �`�s/0NpL EAU Principal MJH:GHS:tt TACO:\11\1 1536002\05Winals\l 153600205R.doex Disclaimer: Any electronic form, facsimile or hard copy of the original document (email, text, table, and/or figure), if provided, and any attachments are only a copy of the original document. The original document is stored by GeoEngineers, Inc.and will serve as the official 4 document of record. File No. 11536-002-05 e TABLE OF CONTENTS Page No. INTRODUCTION........................................................................................................................................... 1 PURPOSEAND SCOPE.............................................................................................................................. 1 GEOLOGYREVIEW.....................................................................................................................................2 SITECONDITIONS.......................................................................................................................................2 PROJECTLOCATION........................................................................................................................2 SURFACECONDITIONS...................................................................................................................2 SUBSURFACE EXPLORATIONS.......................................................................................................2 SUBSURFACECONDITIONS............................................................................................................3 CONCLUSIONS AND RECOMMENDATIONS.............................................................................................3 GENERAL............................................................................................................................................3 SITE DEVELOPMENT AND EARTHWORK.......................................................................................3 General......................................................................................................................................3 Strippingand Clearing...............................................................................................................3 SubgradePreparation...............................................................................................................4 Temporary Excavation Support and Groundwater Handling.....................................................4 Permanent Cut and Fill Slopes..................................................................................................4 SurfaceDrainage.......................................................................................................................5 ErosionControl..........................................................................................................................5 FILLMATERIALS................................................................................................................................5 General......................................................................................................................................5 PipeBedding.............................................................................................................................5 TrenchBackfill...........................................................................................................................6 Useof On-Site Soil....................................................................................................................6 FILL PLACEMENT AND COMPACTION............................................................................................6 General......................................................................................................................................6 AreaFills and Bases..................................................................................................................6 TrenchBackfill...........................................................................................................................6 SEISMICDESIGN CONSIDERATIONS.............................................................................................7 General......................................................................................................................................7 SeismicDesign Criteria.............................................................................................................7 LiquefactionPotential................................................................................................................7 FOUNDATIONSUPPORT..................................................................................................................7 General......................................................................................................................................7 SpreadFootings........................................................................................................................8 LateralLoad Resistance............................................................................................................8 Settlement..................................................................................................................................8 FLOORSLABS...................................................................................................................................8 STORMWATERINFILTRATION.........................................................................................................9 ASPHALTIC CONCRETE PAVEMENT RECOMMENDATIONS .......................................................9 LIMITATIONS..............................................................................................................................................10 File No.11536-002-05 Page i GWENGINEERi September 10,2009 TABLE OF CONTENTS (CONTINUED) Page No. List of Tables Table 1. Seismic Design Parameters 2006 IBC ..........................................................................................7 Table 2. Soil Infiltration Rates Grain-Size Distribution Analysis..................................................................9 List of Figures Figure 1. Vicinity Map Figure 2. Site Plan APPENDICES APPENDIX A—SUBSURFACE EXPLORATIONS AND LABORATORY TESTING Appendix A Figures Figure A-1. Key to Exploration Logs Figures A-2 through A-7. Log of Test Pits Figure A-8. Sieve Analysis Results APPENDIX B— REPORT LIMITATIONS AND GUIDELINES FOR USE I� File No.11536-002-05 Page ii GEOENGINEERSr:U September 10,2009 REPORT GEOTECHNICAL ENGINEERING SERVICES OLYMPIA FEDERAL SAVINGS 24081 NE STATE ROUTE 3 BELFAIR,WASHINGTON FOR MSGS ARCHITECTS INTRODUCTION This report presents the results of our geotechnical engineering services for the proposed Olympia Federal Savings bank located at 24081 NE State Route 3 in Belfair, Washington. The project site is located northwest of State Route 3 approximately as shown on the Vicinity Map, Figure 1. Our understanding of the project and project site is based on information provided by you, an initial site visit on August 14, 2009, and our experience in the Belfair area. We understand preliminary development plans call for a new bank building with a two-lane drive through and possible infiltration swales or pervious pavement for on-site disposal of stormwater. PURPOSE AND SCOPE The purpose of our services is to evaluate soil and groundwater conditions as a basis for developing design criteria for geotechnical aspects of the proposed project. Our specific scope of services for this study includes the following: 1. Reviewing readily available published geologic data and select in-house files for existing information on subsurface conditions in the project vicinity. 2. Locating and coordinating clearance of existing utilities. We contacted the "One-Call Underground Utility Locate Service"prior to beginning explorations. 3. Exploring soil and groundwater conditions at the project site by excavating six test pits to depths of 8-1/2 to 14 feet using a subcontracted rubber-tire backhoe. 4. Performing laboratory tests on selected soil samples obtained from the explorations to evaluate pertinent engineering characteristics. The laboratory test program consisted of four moisture content determinations and four grain-size analyses. 5. Providing recommendations for on-site disposal of stormwater by infiltration. We provide preliminary infiltration rates based on empirical correlations with soil gradation parameters. 6. Providing recommendations for site preparation and fill placement. We include: criteria for clearing, stripping and grubbing; an evaluation of the suitability of on-site soil for use as structural fill; gradation criteria for imported fill,if required; guidance for preparation of subgrade soil, which will support slab-on-grade concrete floors and pavements; and criteria for structural fill placement and compaction. 7. Providing recommendations for design and construction of conventional shallow spread footing foundations, including allowable soil bearing pressures; minimum width and depth criteria; coefficient of friction and equivalent fluid densities for the passive earth pressure state of stress to estimate resistance to lateral loads; estimates of frost penetration; and estimates of foundation settlement. File No.11536-002-05 Page I GEOENGINEERir/P September 10,2009 8. Providing general recommendations for support of on-grade floor slabs including capillary break, vapor retarder, underslab drainage, and an estimate of the modulus of subgrade reaction. 9. Discussing seismic considerations, including seismic design criteria consistent with the 2006 International Building Code(IBC)and our opinion of the liquefaction potential of site soils. 10. Providing recommendations for design of standard-duty asphalt concrete (AC) pavements including: base course gradation, thickness and compaction criteria; and thickness and compaction requirements for AC. GEOLOGY REVIEW Based on review of available published geologic maps, Quaternary Age alluvial soil deposits underlie the project site and surrounding area. The Geologic Map of the Belfair 7.5-minute Quadrangle, Mason, Kitsap and Pierce Counties Washington, (Polenz, Alldritt, Hehemann, Sarikhan, Logan, 2009) indicates the site is underlain by Alluvial fan (Qaf). Qaf is generally described as poorly sorted and stratified silt, sand,gravel and boulders. SITE CONDITIONS PROJECT LOCATION The proposed Olympia Federal Savings project is located at 24081 NE State Route 3 in Belfair, Washington. The site is located northwest of Highway 3 and is bounded by a commercial property to the northeast and a Safeway store to the southwest. Residential properties bound the site to the northwest. SURFACE CONDITIONS The triangular-shaped site has an existing one-story timber construction building with an asphalt concrete parking lot to the southeast of the building. The asphalt concrete pavement at the test pit locations ranges from 1.5 to 2 inches thick and is underlain by about 1 inch of crushed rock. The site slopes gently down to the northwest. There is a moderate slope in the northwest corner of the site. We observed two manholes for a septic system and we understand that there is a septic drain field in the northwest corner of the site. A Mason County drainage and maintenance easement exists along the northeastern boundary of the site. A 4-foot-tall chain link fence bounds the western part of the site and extends along the crest of the cut slope. The cut slope to the west of the chain link fence is inclined at about 2H:1 V (horizontal:vertical) and extends down to a rockery wall that is located on the adjacent Safeway property. The slope above the rockery near the building was observed to be approximately 7 feet high. The rockery wall height ranges from 0 to 12 feet. The wall batter is approximately 8 degrees and the rockery appears to be in relatively good condition based on our visual observations. We did not observe any bowing of the rockery, or, tension cracks in the slope above the rockery at the time of our site visit. The rock size at the base of the rockery was observed to typically be between about 34 and 42 inches wide by about 24 to 28 inches deep. Rock sizes were typically 30 inches wide and 24 inches deep at about mid height in the rockery. We observed that the rockery was keyed into the ground and that there were quarry spalls behind the larger rocks. SUBSURFACE EXPLORATIONS We explored subsurface conditions at the site by excavating six test pits on August 20, 2009 using a rubber-tire backhoe subcontracted by GeoEngineers, Inc. The test pits were excavated to depths of 8-1/2 File No.11536-002-05 Page 2 GEOENGINEER September 10,2009 to 14 feet below ground surface (bgs) at the approximate locations shown on the Site Plan, Figure 2. A more detailed description of the exploration methods and procedures is presented in Appendix A. Figure A-1 presents a key to the exploration logs. Logs of the tests pits are presented as Figures A-2 through A-7. Laboratory test methods and results are also included in Appendix A. SUBSURFACE CONDITIONS Beneath the asphalt concrete pavement, crushed surfacing or an organic-rich surficial layer we encountered materials we interpret to be alluvial fan deposits except at the location of test pits TP-1, TP-5 and TP-6 where we encountered some existing fill material. The fill in test pit TP-1 was observed to be similar in character to the native soil deposits and may have been derived from other areas on the site during grading for the parking lot. The fill in test pit TP-5 consisted of sand with gravel and silt. Test pit TP-5 was located northeast of the septic tank manholes. The fill encountered within the test pit was similar in character to native on-site soils and we interpret it to be backfill from the septic tank installation. The fill in test pit TP-6 consisted of layers of silty sand with gravel and sand with silt and some debris consisting of glass,metal and the lid of a drum. Below the fill,where present, or beneath the surficial layers described above,we encountered native soil that typically consisted of medium dense silty sand, silty gravel or sand with variable silt, and gravel content. No groundwater was observed in our explorations. Seasonal perched groundwater could occur where relatively permeable soil is underlain by a less permeable layer. We expect the amount of perched groundwater and the depth at which it occurs to vary with season and precipitation. CONCLUSIONS AND RECOMMENDATIONS GENERAL Based on our observations, it is our opinion that the proposed Olympia Federal Savings can be constructed generally as envisioned. It is our further opinion on-site infiltration of stormwater is feasible at this site using an infiltration rate of 0.5 inches per hour. The following sections provide geotechnical recommendations for design and construction of the proposed improvements. There is existing fill,which if present within the building area, must be removed to firm and unyielding native soil and replaced with structural fill. SITE DEVELOPMENT AND EARTHWORK General We anticipate that site development work will include removing existing vegetation; demolishing the existing structure; excavating for utility trenches; removing existing fill as necessary and placing and compacting fill and backfill materials. We expect that the majority of site grading can be accomplished with conventional earthmoving equipment in proper working order. The following sections provide recommendations for earthwork, site development and fill materials. Stripping and Clearing Based on our explorations, we anticipate stripping and clearing at this site will be required to remove the existing asphalt concrete or organic-rich topsoil from structural areas. Stripping should extend at least 5 feet beyond building and pavement areas. We estimate that the depth of stripping will generally be on the order of 6 inches or less. Greater stripping depths may be required to remove localized zones of loose or organic soil,or if stripping operations cause excessive disturbance to subgrade soil. File No.11536-002-05 Page 3 GEoENGINEERS.0 September 10,2009 Subgrade Preparation Subgrades should be thoroughly compacted to a uniformly firm and unyielding condition on completion of stripping and before placing structural fill to establish design grade. We recommend subgrade soil be proof-rolled prior to the placement of fill or other structural elements as described below. We recommend that prepared subgrades be observed by a member of our firm, prior to placement of fill or pavement base. Our representative will evaluate the suitability of the subgrade and identify areas of yielding,which are indicative of soft or loose soil. The exposed subgrade soil should be proof-rolled with heavy rubber-tire equipment. If soft or otherwise unsuitable areas are revealed during proof-rolling or probing that cannot be compacted to a stable and uniformly firm condition, we recommend that: 1) the subgrade soils be scarified (e.g., with a ripper or farmer's disc), aerated and recompacted; or 2) the unsuitable soils be removed and replaced with structural fill,as needed. Temporary Excavation Support and Groundwater Handling Based on our explorations, shallow excavations will likely cave unless the sides are appropriately sloped. Excavations deeper than 4 feet should be shored or laid back at a stable slope if workers are required to enter. Shoring and temporary slope inclinations must conform to the provisions of Title 296 Washington Administrative Code (WAC), Part N, "Excavation, Trenching and Shoring." Regardless of the soil type encountered in the excavation, shoring, trench boxes or sloped sidewalls will be required under Washington Industrial Safety and Health Act (WISHA). The contract documents should specify that the contractor is responsible for selecting excavation and dewatering methods,monitoring the excavations for safety and providing shoring,as required,to protect personnel and structures. In general, temporary cut slopes should be inclined no steeper than about 1-1/2H:1V. This guideline assumes that all surface loads are kept at a minimum distance of at least one half the depth of the cut away from the top of the slope and that significant seepage is not present on the slope face. Flatter cut slopes will be necessary where significant seepage occurs or if large voids are created during excavation. Some sloughing and raveling of the cut slopes should be expected. Temporary covering with heavy plastic sheeting should be used to protect slopes during periods of wet weather. Groundwater was not encountered in the explorations. Based on our explorations, we do not anticipate groundwater will be a major factor during shallow excavations and earthwork. We anticipate that the groundwater handling needs will generally be lower during the late summer and early fall months. We anticipate that shallow perched groundwater can be handled adequately with sumps, pumps, and/or diversion ditches, as necessary. Ultimately, we recommend that the contractor performing the work be made responsible for controlling and collecting groundwater encountered. Permanent Cut and Fill Slopes In general, we recommend that permanent cut and fill slopes be constructed at a maximum inclination of f 2H:1V. Where 2H:1V permanent slopes are not feasible, retaining structures should be considered. Cut areas should be re-vegetated as soon as practical to reduce the surface erosion and sloughing. Temporary protection should be used until permanent protection is established. If fill slopes are constructed, we recommend they be overbuilt slightly and subsequently cut back to expose well compacted fill. File No.11536-002-05 Page 4 GEOENGINEERS September 10,2009 Surface Drainage Surface water from roofs, driveways and landscape areas should be collected and controlled. Curbs or other appropriate measures such as sloping pavements, sidewalks and landscape areas should be used to direct surface flow away from the buildings, and erosion sensitive areas. Roof and catchment drains should discharge to an appropriate collection system. Erosion Control Based on existing site grades and the proposed development, we anticipate that erosion control measures such as silt fences, straw bales and sand bags will generally be adequate for the proposed development. However, if construction and grading is staged, slopes may be created and additional erosion control measures may have to be implemented. Temporary erosion control should be provided during construction activities and until permanent erosion control measures are functional. Surface water runoff should be properly contained and channeled using drainage ditches,berms, swales, and tightlines and should not discharge onto sloped areas. Any disturbed sloped areas should be protected with a temporary covering until new vegetation can take effect. Jute or coconut fiber matting, excelsior matting or clear plastic sheeting is suitable for this purpose. Graded or disturbed slopes should be tracked in-place with the equipment running perpendicular to the slope contours so that the track grouser marks provide a texture to help resist erosion. Permanent measures for erosion control should include reseeding or replanting the disturbed areas as soon as possible and protecting those areas until new vegetation has been established. Permanent site grading should be accomplished in such a manner that stormwater runoff is not concentrated and surface water is not directed to sloped portions or into excavated areas of the site not intended for stormwater disposal. This can be accomplished by grading the site to direct the flow to appropriate collection points away from the slopes or excavations. Tightlines should be used where necessary to direct storm or other surface water across sloped areas. Tightlines should be anchored on slopes 15 percent or steeper. FILL MATERIALS General Material used for fill should be free of garbage debris, organic contaminants and rock fragments larger than 6 inches. The suitability of material for use as structural fill will depend on the gradation and moisture content of the soil. As the amount of fines (material passing the U.S. Standard No. 200 sieve) increases, soil becomes increasingly more sensitive to small changes in moisture content and adequate compaction becomes more difficult or impossible to achieve. If construction is performed during wet weather conditions, we recommend using fill consisting of well-graded sand and gravel containing less than 5 percent fines by weight based on the minus 3/4-inch fraction. If prolonged dry weather prevails during the earthwork phase of construction,a somewhat higher fines content may be acceptable. Pipe Bedding Trench backfill for the bedding and pipe zone should consist of well-graded granular material with a maximum particle size of 3/4-inch and less than 5 percent passing the U.S. Standard No. 200 sieve. The material should be free of roots,debris, organic matter and other deleterious material. File No.11536-002-05 Page 5 GEOENGINEERS Od September 10,2009 Trench Backfill We recommend that all trench backfill consist of material of approximately the same quality as "gravel borrow" described in Section 9-03.14(1) of the Washington State Department of Transportation (WSDOT) Standard Specifications. All fills should be constructed in horizontal lifts at the appropriate thickness for compaction. For compaction recommendations refer to the "Fill Placement and Compaction"section of this report. Use of On-Site Soil Based on our subsurface explorations, we conclude that the inorganic mineral native soil may be considered for use as structural fill, provided any oversize particles are removed and it can be placed and compacted as recommended. Large cobbles and boulders can be present in the alluvial fan deposits and will need to be removed before the material can be used as structural fill. The existing fill is not suitable for reuse as structural fill unless all deleterious material is removed. Some of the site soils were observed to have relatively high fines contents, which may make them difficult or impossible to compact when wet or if earthwork is performed during periods of extended wet weather. FILL PLACEMENT AND COMPACTION General Structural fill should be compacted at a moisture content near optimum. The optimum moisture content varies with the soil gradation and should be evaluated during construction. Silty soil and other fine granular soil such as silty sand, silty gravel, sand with silt and gravel with silt can be difficult or impossible to compact during persistent wet conditions. Fill and backfill material should be placed in uniform, horizontal lifts, and uniformly densified with vibratory compaction equipment. The maximum lift thickness will vary depending on the material and compaction equipment used,but should generally not exceed 10 to 12 inches in loose thickness. Area Fills and Bases I Structural fill placed to raise site grades and aggregate base materials under foundations, slabs and pavements should be placed on a prepared subgrade that consists of uniformly firm and unyielding inorganic native soils or compacted fill. Structural fill should be compacted to at least 95 percent of the { maximum dry density (MDD) determined by American Society for Testing and Materials (ASTM) Test Method D 1557(modified Proctor). Trench Backfill For utility excavations, we recommend that the initial lift of fill over the pipe be thick enough to reduce the potential for damage during compaction but generally should not be greater than about 18 inches. In addition, rock fragments greater than about 1 inch in maximum dimension should be excluded from this lift. r In building areas, trench backfill should be uniformly compacted in horizontal lifts to at least 95 percent of the MDD(ASTM D 1557). Fill placed below a depth of 2 feet in pavement areas should be compacted to at least 90 percent of the MDD (ASTM D 1557). In nonstructural areas, trench backfill should be compacted to a firm condition that can support construction equipment. Suitable native soils or select granular soils should be acceptable in non-structural areas. File No.11536-002-05 Page 6 GEoENGINEERS September 10,2009 SEISMIC DESIGN CONSIDERATIONS General The site is located within the Puget Sound region,which is seismically active. Seismicity in this region is attributed primarily to the interaction between the Pacific, Juan de Fuca and North American plates. The Juan de Fuca plate is subducting beneath the North American plate. It is thought that the resulting deformation and breakup of the Juan de Fuca plate might account for the deep focus earthquakes in the region. Hundreds of earthquakes have been recorded in the Puget Sound area. In recent history, four of these earthquakes were large events: 1) in 1946, a Richter magnitude 7.2 earthquake occurred in the Vancouver Island,British Columbia area; 2) in 1949, a Richter magnitude 7.1 earthquake occurred in the Olympia area; 3) in 1965,a Richter magnitude 6.5 earthquake occurred between Seattle and Tacoma; and 4)in 2001 a Richter magnitude 6.8 earthquake occurred in Nisqually,near Olympia,Washington. Geologists report evidence that suggests several large magnitude earthquakes (Richter magnitude 8 to 9) have occurred in the last 1,500 years, the most recent of which occurred about 300 years ago. No earthquakes of this magnitude have been documented during the recorded history of the Pacific Northwest. Seismic Design Criteria We understand seismic design will be performed using the 2006 IBC standards. The following parameters should be used in computing seismic base shear forces: Table 1. Seismic Design Parameters 2006 IBC Spectral Response Accel. at Short Periods(Ss)= 1.33 Spectral Response Accel.at 1 Second Periods(SI)=0.49 Site Class=D Site Coefficient(FA)= 1.0 Site Coefficient(Fv)= 1.5 Liquefaction Potential Liquefaction refers to a condition where vibration or shaking of the ground, usually from earthquake forces, results in development of excess pore pressures in saturated soils and subsequent loss of strength in the deposit of soil so affected. In general, soils that are susceptible to liquefaction include loose to medium dense "clean" to silty sands that are below the water table. In our opinion, the potential for liquefaction at the site is low. FOUNDATION SUPPORT General The proposed Olympia Federal Savings may be satisfactorily founded on continuous wall or isolated column footings established on undisturbed native soil or on structural fill that extends to undisturbed native soil. As discussed above, we recommend existing fill be overexcavated and replaced with structural fill where fill is present at or below foundation grades. The overexcavation must extend laterally beyond the footing perimeter a distance equal to the excavation depth below foundation grade, or 3 feet,whichever is less. We recommend a minimum width of 16 inches for continuous wall footings and File No.11536-002-05 page 7 GMENGINEER� September 10,2009 2 feet for isolated column footings. All footing elements should be embedded at least 18 inches below the lowest adjacent external grade. We recommend installing footing drains to collect and remove possible seasonal perched groundwater. Interior footings should be embedded at least 12 inches below finish floor. We recommend that a member from our firm observe all foundation excavations before formwork and reinforcing steel is placed in order to check that the bearing surfaces have been adequately prepared and that the soil conditions are as anticipated. Loose or disturbed soil should be recompacted or removed and replaced with compacted structural fill as recommended by the geotechnical engineer. Spread Footings Footings founded as described on undisturbed native soil or compacted structural fill may be designed using an allowable soil bearing pressure of 3,000 pounds per square foot (psf). This value applies to long-term dead and live loads exclusive of the weight of the footing and any overlying backfill and may be increased by one-third when considering total loads, including transient loads such as those induced by wind and seismic forces. Lateral Load Resistance Lateral loads on foundation elements may be resisted by passive resistance on the sides of footings and other below-grade structural elements and by friction on the base of footings. Passive resistance may be estimated using an equivalent fluid density of 270 pounds per cubic foot(pcf), assuming that the footings and below-grade elements are backfilled with structural fill placed and compacted as recommended. Frictional resistance may be estimated using 0.35 for the coefficient of base friction. The above values include a factor of safety of about 1.5. Settlement Based on typical single-story construction loads, we estimate that settlement of footings designed and constructed as recommended should be less than 1 inch with differential settlements between comparably loaded isolated footings or along 50 feet of continuous footing of 1/2 inch or less. Most of the settlements should occur essentially as loads are being applied. Loose or soft soil below footings or disturbance of the foundation bearing surface during construction could result in larger settlements than predicted. FLOOR SLABS A modulus of subgrade reaction of 300 pounds per cubic inch(pci)can be used for designing the building floor slab provided that the subgrade consists of undisturbed native soil or structural fill and has been prepared in accordance with the "Site Development and Earthwork" section of this report. Settlement of the floor slab designed and constructed as recommended is estimated to be less than 1 inch. We estimate that differential settlement of the floor slab will be 1/2 inch or less over a span of 50 feet providing that the fill below the slab is compacted as recommended. We recommend that on-grade slabs be underlain by a minimum 6-inch-thick capillary break layer to i reduce the potential for moisture migration into the slab. The capillary break material should consist of a well-graded sand and gravel or crushed rock with a maximum particle size of 3/4 inch and less than 5 percent fines. The material should be placed as recommended in the"Fill Placement and Compaction" section of this report. If dry slabs are required (e.g., where adhesives are used to anchor carpet or tile to ; the slab), a waterproof liner may be placed as a vapor barrier below the slab. File No.11536-002-05 Page 8 GWENGINEERS r September 10,2009 STORMWATER INFILTRATION Select soil samples obtained from test pits TP-2, TP-3 and TP-4 were tested in general accordance with ASTM D 422 to determine the grain size distribution. The results of the grain size distribution testing are presented in Appendix A, Figure A-8. We compared these results with the stormwater rates presented in the 2005 Department of Ecology Stormwater Management Manual for the Puget Sound Basin. Design stormwater infiltration rates for the soil samples obtained are provided in the table below. Table 2. Soil Infiltration Rates Grain-Size Distribution Analysis' Soil Approximate Recommended Soil Sample Elevation of Infiltration Test Sample Depth Sample USCS Soil Rate (inches Pit No. No. (feet) (feet) Soil Description Classification per hour) 2 2 6 94 Sand with Gravel SP 3.5 3 2 2 98.5 Silty Gravel with Sand GM 0.5 4 1 4 94 Silty Sand with Gravel SM 0.5 4 3 12.5 85.5 Silty Sand with Gravel SM 0.5 Notes: For selected soil samples. 2 Based on grain-size analysis in accordance with procedures outlined for ASTM D 422 and in the 2005 Department of Ecology Stormwater Management Manual for the Puget Sound Basin,Tables 3.7 and 3.8. 3 Based on Topographic Survey provided by MSGS Architects. The values presented above are for the samples obtained in a particular area at a particular elevation and represent an estimate of design infiltration rates. Location specific field or laboratory infiltration testing in accordance with local regulations should be performed to develop final design infiltration values. Stormwater should be treated in accordance with current regulations prior to infiltration. ASPHALTIC CONCRETE PAVEMENT RECOMMENDATIONS Pavement subgrades and fill should be prepared and placed as previously described. The crushed rock base course should be moisture-conditioned near the optimum moisture content and compacted to at least 95 percent of the MDD determined in general accordance with ASTM D 1557 test procedures. An appropriate number of in-place density tests should be conducted on the compacted base course to check whether adequate compaction has been obtained. Crushed rock base course should conform to applicable provisions of Sections 4-04 and 9-03.9(3) of the WSDOT Standard Specifications. Hot mix asphalt concrete should conform to applicable sections of 5-04, 9-02 and 9-03 of the WSDOT 2006 Standard Specifications. The recommended pavement sections assume that final improvements surrounding the pavement will be designed and constructed such that stormwater or excess irrigation water from landscape areas does not infiltrate below the pavement section into the crushed base or subbase fill. Standard-Duty Asphalt Concrete Pavement(Automobile Parking Areas) • 2 inches of hot mix asphalt,class 1/2 inch, PG 58-22. • 4 inches of crushed surfacing base course and/or top course compacted as recommended. • Structural fill or native soil subgrade prepared as previously recommended. File No.11536-002-05 Page 9 QoENGINEER� September 10,2009 Heavy-Duty Asphalt Concrete Pavement(Access Roadways) 0 3 inches of hot mix asphalt, class 1/2 inch,PG 58-22. • 6 inches of crushed surfacing base course and/or top course compacted as recommended. • Structural fill or native soil subgrade prepared as previously recommended. The recommended pavement sections may not be adequate for heavy construction traffic conditions such loads imposed by concrete transit mixers, dump trucks, or crane loads. Additional pavement thickness may be necessary to prevent pavement damage during construction, and/or repair of damaged pavements should be anticipated. LIMITATIONS We have prepared this report for the exclusive use by MSGS Architects and their authorized agents for the Olympia Federal Savings project located on State Route 3 in Belfair, Washington. 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, express or implied, should be understood. Please refer to Appendix B titled "Report Limitations and Guidelines for Use" for additional information pertaining to use of this report. t I File No.11536-002-05 Page 10 GWENGINEERS/ September 10,2009 ♦ R % w o • # SITE • N N Q . r Y ' t � a Y J- :. F t x E Maw G 1- .0 N 7 LL "- - - L O N O O N O WE in t Washtnjl s NCN 0 750 0 750 o I d a h~ �� Feet on Notes: Vicinity Map 0 1.The locations of all features shown are approximate. a 2.This drawing is for information purposes.It is intended to assist in showing features discussed in an attached document.GeoEngineers,Inc. Z� can not guarantee the accuracy and content of electronic files.The master Olympia Federal Savings a file is stored by GeoEngineers,Inc.and will serve as the official record of this communication. Belfalr, Washington 3.It is unlawful to copy or reproduce all or any part thereof,whether for U personal use or resale,without permission. < Data Sources: ESRI Data&Maps,Street Maps 2008 Projection:NAD_1983_UTM_Zone_10N G E O E N G I N E E R S Figure 1 u Datum:D North_American w North arrow onented to grid_north O \ 1' ♦ 33yoA ♦♦ / /y TRACT "B" r SS N0. 152 r © A.F. NO. 030581 T� J TRACrT ..A"/ o ♦\\\B9 \ a l l SS NO. 15,2 pD \ r $ A.F. NO. 03D5811 ♦♦ r � � */TP \ / eicsnxc euim/e �• ♦\ \\ naw noa+aev Ioava P TP-2/ SURVEY T _1* / A.F. NO. 462919 AND A.F. NO. 7726736 / g •f0• GEOENGINEERS APPENDIX A SUBSURFACE EXPLORATIONS AND LABORATORY l' TESTING t✓° APPENDIX A SUBSURFACE EXPLORATIONS AND LABORATORY TESTING SUBSURFACE EXPLORATIONS Subsurface conditions at the site were explored on August 20, 2009 by excavating six test pits using equipment and an operator subcontracted to GeoEngineers,Inc. The test pit explorations ranged in depth from 8-1/2 to 14 feet below surrounding site grades. The locations of the test pits were established in the field by pacing from existing site features such as roadways and structures. Locations of the explorations are provided on Figure 2. The elevations presented on the test pit logs are based on interpolation between the topographic contours shown on the site plan provided by MSGS Architects. The locations and elevations of the explorations should be considered approximate. The field explorations were performed under the direction of our personnel. Our field representative obtained samples, classified the soils, maintained a detailed log of each exploration and observed groundwater conditions where applicable. The samples were retained in sealed plastic bags. The soils were classified visually in general accordance with the system described in Figure A-1, which includes a key to the exploration logs. Summary logs of the explorations are included as Figures A-2 through A-7. The relative densities noted on the test pit logs are based on the difficulty of excavation and our experience and judgment. Laboratory test methods and results are described below. LABORATORY TESTING General Soil samples obtained from the test pits were transported to GeoEngineers laboratory. Representative soil samples were selected for laboratory tests to confirm our field classification. The following paragraphs provide a description of the tests performed. Moisture Content The moisture content of selected samples was determined in general accordance with ASTM Test Method D 2216. The test results are used to aid in soil classification and correlation with other pertinent engineering soil properties. The test results are presented on the test pit logs at the respective sample depths. Particle-Size Analyses Particle-size sieve analyses (SA) were performed on selected samples in general accordance with ASTM Test Method D 422. This test method covers the quantitative determination of the distribution of particle sizes in soils. The distribution of particle sizes larger than the U.S. No. 200 sieve (75 micrometers) was determined by mechanical sieving. The results of the tests were used to check field soil classifications. Figure A-8 presents the sieve test results. I File No.11536-002-05 Page A-1 GwENGINEERiJr/P September 10,2009 SOIL CLASSIFICATION CHART ADDITIONAL MATERIAL SYMBOLS SYMBOLS TYPICAL SYMBOLS TYPICAL MAJOR DIVISIONS GRAPH LETTER DESCRIPTIONS GRAPH LETTER DESCRIPTIONS WELL-GRADED GRAVELS,GRAVEL- CLEAN 0 Q° Gyy SAND MIXTURES /�/�j/� CC Cement Concrete GRAVEL GRAVELS AND o O GRAVELLY (LITTLE OR NO FINES)) POORLY-GRADED GRAVELS,GRAVEL- SOILS °G°D GP SAND MIXTURES AC Asphalt Concrete COARSE GRAVELS WITH ° SILTY GRAVELS,GRAVEL•SAND-SILT GRAINED MORE THAN 50%OF GM MIXTURES Crushed Rock/ FINESCR SOILS COARSE FRACTION Quarry Spells RETAINED ON N0.4 SIEVE (APPRECIABLE AMOUNTW/CC CLAYEY GRAVELS,GRAVEL -SPND- OF FINES) GC CLAY MIXTURES TS Topsoil/ Forest Duff/Sod Sw WELLGRADED SANDS,GRAVELLY CLEAN SANDS sANDs MORE THAN 50% SAND RETAINED ON NO. AND (LITTLE OR NO FINES) 200 SIEVE SANDY SP POORLYGRADEDSANDS,GRAVELLY AND Measured groundwater level in SOILS _ exploration,well,or piezometer MORE THAN 50%OF SANDS WITH SM SILTY SANDS,SAND-SILT MIXTURES Groundwater observed at time of COARSE FRACTION FINES PASSING NO.4 exploration SIEVE (APPRECIABLE AMOUNT CI+ CLAYEY SANDS,SAND-CLAY OF FINER) Jl� MIXTURES Perched water observed at time of INORGANIC SILTS,ROCK FLOUR exploration ML PLY C6I�LTsWITH SLIGHT 1 Measured free product in well or INORGANIC CLAYS OF LOW TO piezometer SILTS MEDIUM PLASTICITY,Y,Y,GRAVELLY FINE AND UQUID CL cLAYS.SANDY CLAYS,SILTY CLAYS, Graphic Log Contact CLAYS LEAN CLAYS GRAINED SOILS ORGANIC SILTS AND ORGANIC SILTY Distinct contact between soil strata or OL CLAYS OFLOW PLASTICITY geologic units Approximate location of soil strata MORE THAN 50% I I I I INORGANIC SRTS,MICACEOUS OR PASSING NO.200 MH DUITOMACEOUS SILTY SOILS change within a geologic soil unit SIEVE SILTS UOUIDLIMIT CH NORTGANICCLAYS OFHIGH Material Description Contact AND GREATER THAN 50 CLAYS Distinct contact between soil strata or ORGANIC CLAYS AND SILTS OF geologic units OH MEDIUM TO HIGH PLASTICITY ___ Approximate location of soil strata HIGHLY ORGANIC SOILS — PT PEAT HUMUS,SWAMP SOILS WITH change within a geologic soil unit HIGH ORGANIC CONTENTS NOTE: Multiple symbols are used to indicate borderline or dual soil classifications Laboratory/ Field Tests Sampler Symbol Descriptions %F Percent fines AL Atterberg limits ® 2.4-inch I.D.split barrel CA Chemical analysis CP Laboratory compaction test JI Standard Penetration Test(SPT) CS Consolidation test IDS Direct shear ■ Shelby tube HA Hydrometer analysis MC Moisture content ® Piston MD Moisture content and dry density OC Organic content Direct-Push PM Permeability or hydraulic conductivity PP Pocket penetrometer ® SA Sieve analysis Bulk or grab TX Triaxial compression UC Unconfined compression VS Vane shear Blowcount is recorded for driven samplers as the number of blows required to advance sampler 12 inches(or Sheen Classification distance noted). See exploration log for hammer weight and drop. NS No Visible Sheen SS Slight Sheen A"P"indicates sampler pushed using the weight of the MS Moderate Sheen drill rig. HS Heavy Sheen NT Not Tested NOTE: The reader must refer to the discussion in the report text and the logs of explorations for a proper understanding of subsurface conditions. Descriptions on the logs apply only at the specific exploration locations and at the time the explorations were made;they are not warranted to be representative of subsurface conditions at other locations or times. KEY TO EXPLORATION LOGS 00011*11 GWENGINEERS FIGUREA-1 Date Excavated: 8/20/2009 Logged By: MJH Equipment: Case 580 Extendahoe Total Depth (ft) 8.5 SAMPLE E E m o MATERIAL REMARKS m m o U) z DESCRIPTION a) CM V V a N E N fi O N O N C w I° in H C7 00 00 w AC 1.5 inches asphalt concrete,1 inch crushed rock 41 Red/brown fine to coarse sand with gravel and silt(medium dense,moist) SP-SM (fill) 1 �O 1 � 2 SM Red/brown silty fine to coarse sand with gravel(medium dense,moist) a° 3 z O' 4 �A 5 ce s SP-SM Tan/gray fine to coarse sand with gravel and silt(medium dense,moist) 6 A� 7 8 0`S Test pit completed at 8.5 feet on 8/20/09 ° No groundwater seepage observed a No caving observed a H N ~I W ° F- C7 N K W Z_ Z O w V E E t= m O V F Z C7 Notes: See Figure A-1 for explanation of symbols. The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. a Log of Test Pit TP-1 Project: Olympia Federal Savings a G Eta E N G I N E E R S Project Location: Belfair, Washington Figure A-2 IL Project Number: 11536-002-05 Sheet 1 of 1 Date Excavated: 8/20/2009 Logged By: MJH Equipment: Case 580 Extendahoe Total Depth (ft) 9.5 SAMPLE m is -0 MATERIAL REMARKS A w E E CM U) z - a) DESCRIPTION O L C C > — — O. J y O C O tN ,N 2 O ,p r 00 w F� n F U� (D U W U AC 1.5 inches asphalt concrete,1 inch crushed rock SM Dark brown silty fine to coarse sand with gravel(medium dense,moist) Red/brown silty fine to coarse sand with gravel(medium dense,moist) 09 t SM t A§1 2 9^ 3 06 4 CP S 0Q 6 z SP Tan/gray fine to coarse sand with gravel(medium dense,moist) 4 SA 7 Cti 8 U W r 0 a i ti Test pit completed at 9.5 feet on 8/20/09 No groundwater seepage observed w No caving observed 0 c� N m W W Z U Z W O W 0 E N E r m F z Notes: See Figure A-1 for explanation of symbols. The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. a Log of Test Pit TP-2 Project: Olympia Federal Savings Project Location: Belfair, Washington FigureA-3 Project Number: 11536-002-05 Sheet 1 of 1 Date Excavated: 8/20/2009 Logged By: MJH Equipment: Case 580 Extendahoe Total Depth (ft) 10.0 SAMPLE m is d � E o o MATERIAL w U) z J DESCRIPTION o REMARKS O p, m 07 O w C m.: is L C — C O. j'y :3 N O_ Vl E N (`0 O O 00 m �U W F Cn Fes- U' U~U LU AC 2 inches aspbalt concrete,1 inch crushed rock SM Red/brown silty fine to coarse sand with gravel(medium dense,moist) O� t 2 GM Redibrown silty gravel with sand(medium dense,moist) 0 z g SA A0 3 a 0A q 0 06 5 0 0 0 9 g 0 4' 7 0 A5 g Grades to gray/brown 0 w r r? 0`ti 9 0 H 3 N w a° 10 Test pit completed at 10 feet on 8/20/09 No groundwater seepage observed No caving observed m W W z z w O W m E E t= m F z Notes: See Figure A-1 for explanation of symbols. The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. a 0 Log of Test Pit TP-3 Project: Olympia Federal Savings ❑ Project Location: Belfair, Washington CaEC�ENGINEER Figure� Project Number: 11536-002-05 Sheet 1 of 1 Date Excavated: 8/20/2009 Logged By: MJH Equipment: Case 580 Extendahoe Total Depth (ft) 13.0 SAMPLE iu m MATERIAL REMARKS w (n z DESCRIPTION d N N N cc T O` er C 2U U' U W CR 1 inch crushed rock SM Red/brown silty fine to coarse sand with gravel(medium dense,moist) 9� 1 2 9h 3 0� 4 [ 10 SA 5 4ti 6 9� 7 °A 8 U W r a A 9 2 SM Tan/gray silty fine to coarse sand with gravel(medium dense,moist) N W W !7 W 0A W Z U W O 06 12 E s 10 SA h s 13 Test pit completed at 13 feet on 8/20/09 m No groundwater seepage observed No caving observed a U g F z Notes: See Figure A-1 for explanation of symbols. The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. a 5 Log of Test Pit TP-4 'a Project: Olympia Federal Savings 1ton Pro ect Location: Belfair, Washington g FigureA-5 Project Number: 11536-002-05 Sheet 1 of 1 Date Excavated: 8/20/2009 Logged By: MJH Equipment: Case 580 Extendahoe Total Depth (ft) 14.0 SAMPLE ar m is E E m o 9 MATERIAL DESCRIPTION REMARKS Z N C �N fn J d cct C C 2 j'y =O N a) N N l�D N o C O O u1 I— rn 1- 0 00 w CR 2 inches crushed rock Redibrown fine to coarse sand with silt and gravel(medium dense,moist) Possible septic tank backfill SP-SM (fill) CP 2 9h 3 Ok 4 C;' 5 1 SP/SP-SM Layered graylbrown fine to coarse sand with trace silt and red/brown fine Possible septic tank backfili 6 to coarse sand with silt(medium dense,moist)(fill) 9� 7 �O 8 U F 9 a t a y w 10 w F 0 U 1 w 1 t z P-SM/S Gray/brown fine to coarse sand with silt and gravel interbedded with Zredibrown silty fine to medium sand(medium dense,moist)(native) w a w 12 a E 2 a 0y 13 E 1= m O � 'a 14 Test pit completed at 14 feet on 8/20/09 No groundwater seepage observed No caving observed Notes: See Figure A-1 for explanation of symbols. The depths on the test ph logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. a t a Log of Test Pit TP-5 Project: Olympia Federal Savings Project Location: Belfair,Washington GEOENGINEERS jFigureA-6 Project Number: 11536-002-05 Sheet 1 of 1 • Date Excavated: 8/20/2009 Logged By: MJH Equipment: Case 580 Extendahoe Total Depth (ft) 12.5 SAMPLE m w E E CM MATERIAL REMARKS 0 U) z a) DESCRIPTION U m Ql CM U ;� C c A 7 N d J y O N C U d 2 y E N O ,p U 00 w a) cn F0 C7 00 W �� .. DLTF Forest duff 9h Redibrown silty fine to coarse sand with gravel and trace organics SNVSP-SIAinterbedded with gray fine to coarse sand with silt(medium dense, moist)(fill) 1 z 2 O5 With glass and metal waste 3 4 5 CP 6 SM Red brown silty fine to medium sand with gravel(medium dense,moist) 7 0b 8 3 U 01 w O wU 9 a I r �0 a F y ~I 10 o � N W 11 Z oSP/SM Gray/brown fine to coarse sand with gravel and trace silt interbedded with red/brown silty fine to medium sand(medium dense,moist) 12 4 E 6� Test pit completed at 12.5 feet on 8/20/09 No groundwater seepage observed ENo caving observed m 0 a F z Notes: See Figure A-1 for explanation of symbols. The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. a Log of Test Pit TP-6 Project: Olympia Federal Savings Project Location: Belfair, Washington GMENGINEER FigureA-7 Project Number: 11536-002-05 Sheet 1 of 1 TACO:\11\11536002\05\Finals\1153600205FigureA8.ppt MJH:BAR:mh 090309 U.S.STANDARD SIEVE SIZE 3" 1.5" 3/4" 3/8" 44 910 #20 #40 #60 4100 4200 100 $0 80 70 60 c� z 50 40 30 a 20 10 . 111 , ji I L*� ITTIT m a F. 0 1000 100 10 1 0.1 0.01 0.001 m z GRAIN SIZE IN MILLIMETERS O cn rn a> v' D m 71 m COBBLES GRAVEL SAND SILT OR CLAY LA � N N COARSE FINE COARSE MEDIUM FINE = SYMBOL EXPLORATION DEPTH MOISTURE NUMBER ft SOIL CLASSIFICATION N ca' U' = TP-2 6 4 Fine to coarse sand with gravel(SP) TP-3 2.5 9 Silty fine to coarse gravel with sand(GM) y 0 TP-4 4 10 Silty fine to coarse sand with gravel(SM) TP-4 12.5 10 Silty fine to coarse sand with gravel(SM) r� GWENGINEERS� APPENDIX B REPORT LIMITATIONS AND GUIDELINES FOR USE Y APPENDIX B REPORT LIMITATIONS AND GUIDELINES FOR USE' This appendix provides information to help you manage your risks with respect to the use of this report. GEOTECHNICAL SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES, PERSONS AND PROJECTS This report has been prepared for the exclusive use by MSGS Architects and their authorized agents. This report may be made available to regulatory agencies for review. This report is not intended for use by others, and the information contained herein is not applicable to other sites. GeoEngineers structures our services to meet the specific needs of our clients. For example, a geotechnical or geologic study conducted for a civil engineer or architect may not fulfill the needs of a construction contractor or even another civil engineer or architect that are involved in the same project. Because each geotechnical or geologic study is unique, each geotechnical engineering or geologic report is unique, prepared solely for the specific client and project site. Our report is prepared for the exclusive use of our Client. No other party may rely on the product of our services unless we agree in advance to such reliance in writing. This is to provide our firm with reasonable protection against open-ended liability claims by third parties with whom there would otherwise be no contractual limits to their actions. Within the limitations of scope, schedule and budget, our services have been executed in accordance with our Agreement with the Client and generally accepted geotechnical practices in this area at the time this report was prepared. This report should not be applied for any purpose or project except the one originally contemplated. A GEOTECHNICAL ENGINEERING OR GEOLOGIC REPORT IS BASED ON A UNIQUE SET OF PROJECT-SPECIFIC FACTORS This report has been prepared for MSGS Architects for the Proposed Olympia Federal Savings project located in Belfair, Washington. GeoEngineers considered a number of unique, project-specific factors when establishing the scope of services for this project and report. Unless GeoEngineers specifically indicates otherwise,do not rely on this report if it was: • not prepared for you, • not prepared for your project, • not prepared for the specific site explored,or • completed before important project changes were made. For example, changes that can affect the applicability of this report include those that affect: • the function of the proposed structure; • elevation,configuration, location,orientation or weight of the proposed structure; • composition of the design team; or • project ownership. Developed based on material provided by ASFE,Professional Firms Practicing in the Geosciences;www.asfe.org. File No.11536-002-05 Page B-1 GEOENGINEER� September 10,2009 If important changes are made after the date of this report, GeoEngineers should be given the opportunity to review our interpretations and recommendations and provide written modifications or confirmation, as appropriate. SUBSURFACE CONDITIONS CAN CHANGE This geotechnical or geologic report is based on conditions that existed at the time the study was performed. The findings and conclusions of this report may be affected by the passage of time, by manmade events such as construction on or adjacent to the site, or by natural events such as floods, earthquakes, slope instability or groundwater fluctuations. Always contact GeoEngineers before applying a report to determine if it remains applicable. TOPSOIL For the purposes of this report, we consider topsoil to consist of generally fine-grained soil with an appreciable amount of organic matter based on visual examination, and to be unsuitable for direct support of the proposed improvements. However, the organic content and other mineralogical and gradational characteristics used to evaluate the suitability of soil for use in landscaping and agricultural purposes was not determined, nor considered in our analyses. Therefore, the information and recommendations in this report, and our logs and descriptions should not be used as a basis for estimating the volume of topsoil available for such purposes. MOST GEOTECHNICAL AND GEOLOGIC FINDINGS ARE PROFESSIONAL OPINIONS Our interpretations of subsurface conditions are based on field observations from widely spaced sampling locations at the site. Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. GeoEngineers reviewed field and laboratory data and then applied our professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. Our report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions. GEOTECHNICAL ENGINEERING REPORT RECOMMENDATIONS ARE NOT FINAL Do not over-rely on the preliminary construction recommendations included in this report. These recommendations are not final, because they were developed principally from GeoEngineers' professional judgment and opinion. GeoEngineers' recommendations can be finalized only by observing actual subsurface conditions revealed during construction. GeoEngineers cannot assume responsibility or liability for this report's recommendations if we do not perform construction observation. Sufficient monitoring, testing and consultation by GeoEngineers should be provided during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether or not earthwork activities are completed in accordance with our recommendations. Retaining GeoEngineers for construction observation for this project is the most effective method of managing the risks associated with unanticipated conditions. A GEOTECHNICAL ENGINEERING OR GEOLOGIC REPORT COULD BE SUBJECT TO MISINTERPRETATION Misinterpretation of this report by other design team members can result in costly problems. You could lower that risk by having GeoEngineers confer with appropriate members of the design team after File No.11536-002-05 Page B-2 GEOENGINEERi.05) September 10,2009 submitting the report. Also retain GeoEngineers to review pertinent elements of the design team's plans and specifications. Contractors can also misinterpret a geotechnical engineering or geologic report. Reduce that risk by having GeoEngineers participate in pre-bid and preconstruction conferences, and by providing construction observation. DO NOT REDRAW THE EXPLORATION LOGS Geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering or geologic report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk. GIVE CONTRACTORS A COMPLETE REPORT AND GUIDANCE Some owners and design professionals believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give contractors the complete geotechnical engineering or geologic report, but preface it with a clearly written letter of transmittal. In that letter, advise contractors that the report was not prepared for purposes of bid development and that the report's accuracy is limited; encourage them to confer with GeoEngineers and/or to conduct additional study to obtain the specific types of information they need or prefer. A pre- bid conference can also be valuable. Be sure contractors have sufficient time to perform additional study. Only then might an owner be in a position to give contractors the best information available, while requiring them to at least share the financial responsibilities stemming from unanticipated conditions. Further, a contingency for unanticipated conditions should be included in your project budget and schedule. 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 on-site 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. GeoEngineers includes these explanatory "limitations" provisions in our reports to help reduce such risks. Please confer with GeoEngineers if you are unclear how these "Report Limitations and Guidelines for Use" apply to your project or site. GEOTECHNICAL, GEOLOGIC AND ENVIRONMENTAL REPORTS SHOULD NOT BE INTERCHANGED The equipment, techniques and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical or geologic study and vice versa. For that reason, a geotechnical engineering or geologic report does not usually relate any environmental findings, conclusions or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Similarly,environmental reports are not used to address geotechnical or geologic concerns regarding a specific project. File No.11536-002-05 Page B-3 GWENGINEER;.!/ September 10,2009 BIOLOGICAL POLLUTANTS GeoEngineers' Scope of Work specifically excludes the investigation, detection, prevention, or assessment of the presence of Biological Pollutants in or around any structure. Accordingly, this report includes no interpretations, recommendations, findings, or conclusions for the purpose of detecting, preventing, assessing, or abating Biological Pollutants. The term "Biological Pollutants" includes, but is not limited to,molds, fungi, spores,bacteria,and viruses,and/or any of their byproducts. File No.11536-002-05 Page B-4 GWENGINEER� September 10,2009 Olympia Federal Savings Issued for Permit/Bid: 1-7-10 New Branch Building MSGS Project No.08-122 DOCUMENT 00 72 14 GENERAL CONDITIONS (SINGLE-PRIME CONTRACT) 1.1 SUMMARY A. Document Includes: 1. General Conditions by reference. 1.2 GENERAL CONDITIONS A. AIA Document A201-2007,General Conditions of the Contract for Construction,is the General Conditions of the Contract. 1.3 CLARIFICATIONS A. Article 3, Paragraph 3.7.1: Mason County Building Department is the permitting jurisdiction. The actual cost of building permit(only)and the public utility hookup fees will be a direct reimbursement to the Contractor or paid directly to the permitting agency by the Owner. Fees for these permits should not be included by the Bidder in the bid amount. END OF DOCUMENT General Conditions—AIA Stipulated Sum (Single-Prime Contract) 007214- 1 L Mason County Review Checklist For a Geotechnical Report Instructions: This checklist is intended to assist Staff in the review of a Geotechnical Report. The Geotechnical Report is reviewed for completeness with respect to the Resource Ordinance. If an item is found to be not applicable, the Report should explain the basis for the conclusion. The Report is also reviewed for clarity and consistency. If the drawings, discussion, or recommendations are not understandable, they should be clarified. If they do not appear internally consistent or consistent with the application or observations on site, this needs to be corrected or explained. If resolution is not achieved with the author, staff should refer the case to the Planning Manager or Director. Applicant's Name: �TiPt / L3vvlitJ�l Permit# cau tB ° OD( S'Parcel# Z 3 'rj Z_ p_�i/,c v� 6&o J 2 Date(s)of the Document(s) reviewed: ' (1) (a)A disc ssion of general geologic conditions in the vicinity of the proposed development, OK? Comment: (b) A d's ussion of specific soil types OK? Comment: (c) A d ussion of ground water conditions OK?�_Comment: (d) A dis ussion of the upslope geomorphology OK? _Comment: (e) A dis ussion of the location of upland waterbodies and wetlands OK? i Comment: (f) A discussion of history of landslide activity in the activity in the vicinity, as available in the refer nced maps and r"�s a OK?Y Comment: (2) A site I n which identifies the important development and geologic features. OK?Y Comment: (3) Locati and logs of exploratory holes or probes. OK? Comment: (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. OK?_�5, Comment: (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. OK? X Comment: (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 coeffients should be a value of 0.15. OK? k Comment: (7) (a)Appropriate restrictions on placement of drainage features OK? ,,- Comment: (b) Appropriate restrictions on placement of septic drain fields OK? 5—*:'- Comment: (c) Appropriate restrictions on placement of compacted fills and footings OK? SC Comment: (d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other slopes on the property. Page 1 of 2 Form Effective June 2008 i OK? Comment: (e) ecommended setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes on the property. OK? ,IC Comment: (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. OK? X Comment: (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 frppm erosion, landslides and harmful construction methods. OK? K Comment: (10) An analysis of both on-site and off-site impacts of the proposed development. OK? k Comment: (11) Specifications of final development conditions such as, vegetative management, drainage, erosion trol, and buffer widths. OK? k Comment: (12) Recommendations for the preparation of structural mitigation or details of other proposed mitigation. OK? Comment: (13) A site map drawn to scale showing the property boundaries, scale, north arrow, and the location and nVe of existing and proposed development on the site. OK? Comment: Are the Documents signed and 'stamped? Type and #of License: L(: If not approved, what is the next action/recommendation for further action? Reviewed by , on Time spent in review: SECOND REVIEW/UPDATE: Reviewed by , on Time spent in second review: THIRD REVIEW/UPDATE: Reviewed by , on Time spent in third review: Disclaimer: Mason County does not certify the quality of the work done in this Geological Assessment Page 2 of 2 Form Effective June 2008 I Mason County Department of Community Development Submittal Checklist For a Geotechnical Report 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 found to be not applicable, the report should explain the basis for the conclusion. i i Applicant/Owner Olympia Federal Savings Parcel#_123283290000 Site Address 24081 NE State Route 3, Belfair, Washington (1) (a)A discussion of general geologic conditions in the vicinity of the proposed development, Located on page(s) 2 _ (b) A discussion of specific soil types Located on page(s) 3 (c) A discussion of ground water conditions Located on page(s) 3 (d) A discussion of the upslope geomorphology Located on page(s) 2 j (e) A discussion of the location of upland waterbodies and wetlands Located on page(s) None observed (f) A discussion of history of landslide activity in the activity in the vicinity, as available in the referenced maps and records Located on page(s)_ P2 and Addendum (2) A site plan which identifies the important development and geologic features. Located on Map(s)_ Figures 1 and 2 (3) Locations and logs of exploratory holes or probes. Located on Map(s)_ Figure 2 (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) N/A (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)_ N/A (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 coeffients should be a value of 0.15. Located on page(s) N/A (7) (a)Appropriate restrictions on placement of drainage features Located on page(s) N/A (b) Appropriate restrictions on placement of septic drain fields Located on page(s) N/A (c) Appropriate restrictions on placement of compacted fills and footings Located on page(s) N/A Page 1 of 2 Form Effective June 2008 Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report. (d) Recommended buffers from the landslide hazard areas shoreline bluffs and the tops of other slopes on the property. Located on page(s) NIA (e) Recommended setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes on the property. Located on page(s) NIA (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) N/A (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) N/A (10) An analysis of both on-site and off-site impacts of the proposed development. Located on page(s) NIA (11) Specifications of final development conditions such as, vegetative management, drainage, erosion control,and buffer widths. Located on page(s) N/A (12) Recommendations for the preparation of structural mitigation or details of other proposed mitigation. Located on page(s) N/A (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) N/A l Garry H.Squires,PE,LG, LEG 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 licensed in the State of Washington with special knowledge of the local conditions. 1-also ee+S44,gt the Geotechnical September 10,2009 �� To the best of my Report, datec,and February 16,2010and entitled professional knowledge Olympia Federal Savings Building Replacement meets all the requirements of the Mason County Resource Ordinance, Landslide Hazard Section, is complete and true, that the assessment demonstrates conclusively that the risks posed by the landslide hazard can be mitigated through the included geotechnical design recommendations, and that all hazards are mitigated in such a manner as to prevent harm to property and public health and safety. (Signature and Stamp) ash% ngin"ring cora;}is GAF�FdY �q Page 2 of 2 Form Effective June 2008 Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report.