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Report (3) t` I" CXot3 RECEIVED OFFICE COPY '� (� Qazi JUL O o z02.i GEC) ESINs CITY OFTcr AN N V 5 COMPANY BUILDING 1kt1gib" W ( ' I REPORT OF GEOTECHNICAL ENGINEERING SERVICES Terrace Glenn Apartments 9640 SW Greenburg Road Tigard, Oregon For Related Northwest 16. December 31, 2020 GeoDesign Project: RelatedNW-2-01 III ew r G EO DESIGNY AN N V 5 COMPANY December 31, 2020 t Related Northwest tat 208 SW First Avenue, Suite 240 Portland, OR 97204 wr Attention: Ryan Hood Report of Geotechnical Engineering Services Terrace Glenn Apartments tot 9640 SW Greenburg Road Tigard, Oregon GeoDesign Project: RelatedNW-2-01 GeoDesign, Inc. is pleased to submit this report of geotechnical engineering services for the proposed Terrace Glenn Apartments project located at 9640 SW Greenburg Road in Tigard, Oregon. Our services for this project were conducted in general accordance with our proposal dated September 22, 2020 and our change order dated November 24, 2020. w�. We appreciate the opportunity to be of service to you. Please call if you have questions regarding this report. Sincerely, ism GeoDesign, Inc. tom ff1 Brett A. Shipton, P.E., G.E. Principal Engineer tit RTL:BAS:kt Attachments One copy submitted(via email only) Document ID: RelatedNW-2-01-123120-geor.docx ©2020 GeoDesign,Inc. All rights reserved. 9450 SW Commerce Circle,Suite 300 I Wilsonville,OR 97070 I 503.968 8787 www.geodesigninc.com wm EXECUTIVE SUMMARY This report presents the results of our geotechnical engineering evaluation for the proposed Terrace Glenn Apartments project located at 9640 SW Greenburg Road in Tigard, Oregon. The proposed project includes the construction of two new, four-story apartment buildings. The buildings will be constructed using wood framing and will have footprints of approximately 17,751 and 15,680 square feet. The proposed buildings do not have basements. The development will also include construction of retaining walls, paved parking areas, paved drive aisles, underground utilities, and landscape areas. SW Greenburg Road half-street improvements will also be performed as part of this project. The site is 2.88 acres in size. The site is currently occupied by a church, a two-story residence, AC pavement, landscaping, an orchard an outdoor deck, and vacant areas. The existing structures will be demolished as part of this project. The site location relative to surrounding L physical features is shown on Figure 1. Based on our review of the available information and the results of our explorations, it is our opinion that the site can be developed as proposed. Our specific recommendations for site development and design are provided later in this report. The following items will have an impact on design and construction of the proposed project: • The proposed buildings can be supported on spread footings that are underlain by firm native soil or structural fill. It may be necessary to over-excavate soft undocumented fill soil at some locations prior to footing construction or structural fill placement. • The structural fill that is placed beneath new buildings to raise grades will result in settlement. Once the structural fill has been placed, we recommend that the construction of foundations, floor slabs, and other structures be delayed until it is verified that fill-induced settlement is complete. • If new fill is placed next to existing structures, the weight of the new fill could cause settlement beneath existing structures. We note that the foundations of the existing buildings to the north of the site are within a few inches of the property line. We recommend that new fill not be placed near existing structures. Alternatively, settlement damage can ""' also be mitigated by using lightweight fill or installing ground improvement. • We measured relatively low infiltration rates in our explorations. Stormwater infiltration will likely be limited at the site. • Liquefaction, lateral spreading, fault rupture, landslides, and flooding are not considered hazards at the site. • Our seismic analysis indicates that design levels of ground shaking can be computed ANN assuming Site Class D in accordance with ASCE 7-16. It may be necessary to perform a site- specific seismic analysis for the proposed buildings, depending on the results of analyses performed by the structural engineer. If necessary, we can perform this additional seismic analysis. • The on-site soil is suitable for use as structural fill, provided it is properly moisture conditioned. tAga „ DESIGNZ ANN V''5coa+vxrer i RelatedNW-2-01:1 23120 xw TABLE OF CONTENTS PAGE NO. ACRONYMS AND ABBREVIATIONS 1.0 INTRODUCTION 1 2.0 PURPOSE AND SCOPE 1 3.0 SITE CONDITIONS 2 3.1 Regional and Site Geology 2 3.2 Surface Conditions 3 3.3 Subsurface Conditions 3 3.4 Infiltration Testing 4 4.0 GEOLOGIC HAZARDS 5 w 4.1 Seismic Hazards 5 4.2 Other Geologic Hazards 6 5.0 DESIGN RECOMMENDATIONS 6 5.1 Foundation Support 6 5.2 Slabs on Grade 7 5.3 Seismic Design Parameters 8 5.4 Fill-Induced Settlement 8 5.5 On-Site Pavement Recommendations 10 5.6 Retaining Walls 11 5.7 Permanent Slopes 13 5.8 Drainage 13 rw 6.0 CONSTRUCTION RECOMMENDATIONS 13 6.1 Site Preparation 13 6.2 Excavation 14 6.3 Structural Fill 15 6.4 Erosion Control 18 6.5 Wet Weather Construction 18 7.0 OBSERVATION OF CONSTRUCTION 18 8.0 LIMITATIONS 19 +00. REFERENCES 21 FIGURES m"+ Vicinity Map Figure 1 Site Plan Figure 2 Surcharge-Induced Lateral Earth Pressures Figure 3 aim ams [ DESIGNN V'5eomPoo RelatedNW-2-01:1 231 20 .- _ r tie TABLE OF CONTENTS PAGE NO. r- APPENDICES as Appendix A Field Explorations A-i iv Laboratory Testing A-2 iiii. Exploration Key Table A-1 Soil Classification System Table A-2 Boring Logs Figures A-1 -A-10 iiir Atterberg Limits Test Results Figure A-1 1 Consolidation Test Results Figure A-12 Summary of Laboratory Data Figure A-13 Appendix B Nearby Explorations B-1 iii Figures, Logs, and Laboratory Test Results Appendix C Infiltration Test Data C-1 Infiltration Test Data tim I ii, I I oho GEODESIGN= AN NV S „„ RelatedNW-2-01:123120 mott UAW ACRONYMS AND ABBREVIATIONS AASHTO American Association of State Highway and Transportation Officials m'" AC asphalt concrete ACP asphalt concrete pavement ASCE American Society of Civil Engineers ASTM American Society for Testing and Materials BGS below ground surface CRBG Columbia River Basalt Group DCP dynamic cone penetrometer DOGAMI Oregon Department of Geology and Mineral Industries g gravitational acceleration (32.2 feet/secondz) Agit H:V horizontal to vertical IBC International Building Code �+r MCE maximum considered earthquake MCEC maximum considered earthquake geometric mean OSHA Occupational Safety and Health Administration OSHPD Office of Statewide Health Planning and Development OSSC Oregon Standard Specifications for Construction (2021) pcf pounds per cubic foot mot pci pounds per cubic inch PG performance grade PGA peak ground acceleration wog PGAM maximum considered earthquake geometric mean peak ground acceleration adjusted for site affects psf pounds per square foot psi pounds per square inch SEAOC Structural Engineers Association of California SOSSC State of Oregon Structural Specialty Code *NM SPT standard penetration test USGS U.S. Geological Survey EMI oAet CADESIGN V'5C2MRr Y RelatedNW-2-01.17R170 . 1.0 INTRODUCTION This report presents the results of our geotechnical engineering evaluation for the proposed Terrace Glenn Apartments project located at 9640 SW Greenburg Road in Tigard, Oregon. The proposed project includes the construction of two new, four-story apartment buildings. The buildings will be constructed using wood framing and will have footprints of approximately 17,751 and 15,680 square feet. The proposed buildings do not have basements. The development will also include construction of retaining walls, paved parking areas, paved drive aisles, underground utilities, and landscape areas. SW Greenburg Road half-street improvements will also be performed as part of this project. The site is 2.88 acres in size. The site is currently occupied by a church, a two-story residence, AC pavement, landscaping, an orchard, an outdoor deck, and vacant areas. The existing structures will be demolished as part of this project. The site location relative to surrounding physical features is shown on Figure 1. Foundation loads for the proposed buildings are not currently available. Based on our experience with similar projects,we have assumed that maximum column and wall loads will not exceed 300 kips and 6 kips per foot, respectively. A preliminary project grading plan shows fills of up to approximately 11 feet and cuts of up to approximately 5 feet. We should be contacted to re-evaluate our recommendations if the structural loads, cuts, or fills exceed these values we used in our design. Acronyms and abbreviations used herein are defined above, immediately following the Table of Contents. 2.0 PURPOSE AND SCOPE The purpose of this evaluation was to provide geotechnical engineering recommendations for 610 use in design and construction of the proposed development. Specifically, we completed the following scope of services: • Reviewed readily available, published geologic data and our in-house files for existing information on subsurface conditions in the site vicinity and our previous explorations at nearby surrounding sites. • Coordinated and managed the field explorations, including utility locates, coordination with existing property owners, traffic control, obtaining a Washington County permit, and scheduling subcontractors. • Explored subsurface conditions by drilling the following borings using a trailer-mounted, solid-stem drill rig: • Four on-site borings to depths between 20.1 and 22.7 feet BGS in building areas. • Four on-site borings to depths between 5.5 and 9.5 feet BGS in pavement areas. • Three off-site borings to depths between 0.9 foot and 5 feet BGS in SW Greenburg Road where half-street improvements will be performed. • Performed falling head infiltration tests in four borings at locations and depths where stormwater infiltration is being considered. ita ( i DESIGN% AN V 5 CrIMPArar 1 RelatedNW 2 01:123120 rw • Collected soil samples for laboratory testing and maintained detailed logs of subsurface conditions encountered in the explorations. • Conducted a laboratory testing program that consisted of the following tests: tom • Fifteen moisture content determinations in general accordance with ASTM D2216 • Four particle-size analyses in general accordance with ASTM D1 140 • One Atterberg limits test in general accordance with ASTM D4318 • One consolidation test in general accordance with ASTM D2435 • Provided recommendations for site preparation, grading and drainage, compaction criteria for both on-site and imported materials, fill type for imported material, procedures for use of on-site soil, and wet weather earthwork procedures. ;, • Evaluated groundwater conditions at the site and provided general recommendations for wrr dewatering during construction and subsurface drainage, if required. • Provided recommendations for the use of on-site native and fill material for support of slabs on grade. 1 iii • Provided building foundation support recommendations, including preferred foundation type, allowable bearing pressure, lateral resistance parameters, and settlement estimates. ii • Provided recommendations for use in design of conventional retaining walls, including ,, backfill and drainage requirements and lateral earth pressures. ip • Provided recommendations for on-site AC pavement design and pavement subgrade ''; preparation. m • Provided seismic design coefficients as prescribed by the 2019 SOSSC. • Provided recommendations for wet weather construction. • Prepared this geotechnical engineering report that presents our findings, conclusions, and recommendations. 3.0 SITE CONDITIONS vow 3.1 REGIONAL AND SITE GEOLOGY ' The Portland metropolitan area is situated within the Puget-Willamette Trough physiographic = province, a north-south structural basin lying between the Coast Range to the west and the Cascade Range to the east (Burns, 1998; Orr and Orr, 1999). The subsided lowland of the Portland Basin, a major component of the Willamette Trough, is bound by the anticlinal Tualatin Mountains and the Cascade front (both at least partly controlled by northwest-trending faults) and extends from highlands at Oregon City north to St. Helens and Woodland. `,,," A review of published geologic literature, previous explorations in the area, and explorations conducted during our investigation indicates the site is underlain by Pleistocene flood deposits (Ma et al., 2012) delineated as fine flood deposits (Mff). The unit consists of white or tan sand "w and silt that were deposited in a series of distinct layers. Each layer is a few inches to a few feet thick and represents a single flood. The unit was deposited by multiple catastrophic glacial floods associated with the late Pleistocene Missoula Floods. iwi Underlying the flood deposits is the Pliocene to Pleistocene Age (5 million to 1.5 million years before present)Troutdale Formation (Tpt), which consists of poorly indurated gray and brown silt Alp and clay, mottled yellow and reddish-brown silty fine sand, with occasional pebble conglomerate beds (Schlicker and Deacon, 1967). (W„ DESIGN .ry V:50D oarav 2 RelatedNW-2-01:1 231 20 OW The Troutdale Formation is underlain by the Miocene Age (20 million to 10 million years before present) CRBG (Tcr), which is a series of basalt flows that originated from southeastern Washington and northeastern Oregon. The unit consists of weathered and unweathered basaltic lava flows with interflow zones of breccia, ash, and baked soil (Schlicker and Deacon, 1967). The CRBG is several hundred feet thick and is considered the geologic basement unit for this report. we Subduction of the Juan de Fuca Plate beneath the west margin of the North American Plate presents the potential for great plate-interface earthquakes (magnitude greater than 8). Paleoseismic investigations indicate that plate interface earthquakes have an average recurrence " of 500 to 600 years (Atwater and Hemphill-Haley, 1997; Goldfinger et al., 2003) and that the last subduction zone earthquake occurred in the year 1700 (Satake et al., 1996). Moderate intensity and long duration ground shaking would be expected at the site in the event of a large tee magnitude Cascadia plate-interface earthquake. Crustal faults are present in the site vicinity. The closest faults to the site are the Canby-Molalla fault and the Beaverton fault zone, which are located approximately 1.4 and 2.4 miles from the site, respectively (USGS, 2020). we 3.2 SURFACE CONDITIONS The site is a 2.88-acre lot that is bound by SW Greenburg Road on the west, an apartment complex on the north, and single-family residences on the east and south. The site is currently occupied by a church, a two-story residence, AC pavement, landscaping, an orchard, an outdoor deck, and vacant areas. The existing structures will be demolished as part of this project. Vegetation at the site consists of an orchard, landscape trees, dense brush, shrubs, and lawn. The topography of the site slopes down from west to east, with ground surface elevations ranging from approximately 256 feet on the west to 233 feet on the east. Historical aerial photographs show that significant development has not occurred at the site in at least 25 years. 3.3 SUBSURFACE CONDITIONS We conducted a subsurface exploration program that consisted of drilling 11 borings (B-1 through B-11) to depths between 0.9 foot and 22.7 feet BGS at the approximate locations shown on Figure 2. Descriptions of the field exploration and laboratory testing programs, logs of the ONO explorations, and laboratory test results are presented in Appendix A. Logs for explorations that were performed on the property to the north of the site are presented in Appendix B. We encountered AC pavement or topsoil in our explorations, which is underlain by layers of fill, silt, clay, and gravel. Each of these deposits is described below. 3.3.1 Pavement Section One of our on-site borings was drilled through AC pavement. The AC pavement in boring B-1 is approximately 2 inches thick and is underlain by approximately 4 inches of base rock. We drilled three off-site borings in SW Greenburg Road. The AC pavement is 11 to 11.5 inches thick and is underlain by 3.5 to 7 inches of base rock. [I DESIGN= AN N.Vt5 c +PA+�w d,.` 3 RelatedNW-2-01:123120 km 3.3.2 Topsoil We encountered topsoil in our on-site borings that were drilled in areas that are not paved. The topsoil is approximately 2 to 4 inches thick and generally consists of a mixture of roots and silt. ills, We also observed disturbed loose soil that we interpret as a tilled zone that extends to depths of 6 to 12 inches BGS. 3.3.3 Fill We encountered fill in boring B-3 at the ground surface that extends to a depth of 1.5 feet BGS. , L This fill consists of approximately 6 inches of soft silt that is underlain by approximately 12 inches of medium dense, brown gravel with silt and sand. The gravel is fine and angular to subrounded. Fill soil generally exhibits variable strength and compressibility properties. Naio 3.3.4 Silt We encountered a layer of silt in the on-site borings we drilled for this project. The silt extends to depths between 10 and 15 feet BGS. The silt is generally medium stiff to very stiff, light brown to brown, moist to wet, non-plastic to low plasticity, and contains varying amounts of fine- grained sand. Laboratory testing indicates the moisture content of this layer ranged from 15 to 31 percent at the time of our explorations. Soil such as this generally exhibits moderate strength and low compressibility. Most of our borings were terminated in the silt layer. We performed DCP tests in the silt layer in borings B-5 through B-8. 3.3.5 Clay We encountered a layer of clay beneath the silt in borings B-1 through B-4. The clay extends to depths between 17 and 19 feet BGS. The clay is generally stiff, brown to red, moist, has medium to high plasticity, and contains trace sand. Laboratory testing indicates the moisture content of this layer ranged from 25 to 33 percent at the time of our explorations. Soil such as this Wit generally exhibits moderate strength and low compressibility. 3.3.6 Gravel ""'' We encountered gravel beneath the clay in borings B-1 through B-4. The gravel is generally very dense, red-brown to brown, moist to wet, fine to coarse, subrounded, and contains varying amounts of fine to coarse sand. In boring B-2 we observed the upper portion of this layer to tom consist primarily of sand with subordinate amounts of gravel. The gravel layer appears to be decomposed basalt. Borings B-1 through B-4 were terminated in this layer. Soil such as this 5 generally exhibits high strength and very low compressibility. 3.3.7 Groundwater We observed groundwater in borings B-1 through B-4 at depths between 17.8 and 20 feet BGS. The groundwater appeared ppeared to generally be located near the top of the gravel. We also observed perched water zones at shallower depths of 8 to 10 feet BGS. We note that the depth to groundwater may fluctuate in response to seasonal changes, changes in surface topography, and usi other factors. 3.4 INFILTRATION TESTING We performed infiltration tests in borings B-1, B-2, B-4, and B-6 at depths of 4 to 5 feet BGS. We performed infiltration testing to evaluate infiltration rates at the depths where infiltration is being CEODESIGN= 4P'NV 15 ,"Y 4 RelatedNW-2-01:1 231 20 considered. We also attempted to perform an infiltration test in boring B-8 at a depth of 8 feet BGS, but were unable to perform the test because perched water was seeping into the borehole. We performed the infiltration tests inside of pipes that we inserted into the boreholes. We used the encased falling head test method and a water head of approximately 3 to 4 feet. We collected representative soil samples below the infiltration test depths for particle-size analysis. Table 1 summarizes the infiltration test results and fines content determinations. The exploration logs and laboratory test results are presented in Appendix A. Plots of the infiltration data we collected are presented in Appendix C. Table 1. Measured Infiltration Rates erw Location Depth Material Infiltration Rate' Fines Content2 (feet BGS) (inches per hour) (percent) B-1 5 Silt with sand 0.8 84 B-2 5 Silt with sand 0.5 84 B-4 5 Silt 1.0 86 B-6 4 Silt 0.9 85 1. Infiltration rate is not factored. 2. Fines content: material passing the U.S.Standard No.200 sieve The infiltration rates provided in Table 1 are measured rates and are unfactored. Factors of safety should be applied to the measured infiltration rates by the civil engineer during design to w account for soil variations, the potential for long-term clogging due to siltation and buildup of ko organic material, maintenance, influent/pre-treatment control, and consequences of failure. We recommend that a factor of safety of at least 2 be applied to the field-measured infiltration rates. Based on the infiltration rates we measured at the site, it appears that the silt layer we tested has a relatively low infiltration rate. We note that the silt layer was relatively uniform, and we VAN anticipate that infiltration rates at other depths in the silt layer will be similar to what we measured. If on-site infiltration is used for this project, we recommend that infiltration testing be performed during construction to verify that the design infiltration rates are being achieved. We recommend that all infiltration facilities be at least 10 feet below the bottom of any adjacent on- site or off-site basements. 4.0 GEOLOGIC HAZARDS We evaluated geologic hazards in the site vicinity based on a review of published literature and 440 our experience with nearby projects. Individual geologic hazards are summarized in the following sections. 4.1 SEISMIC HAZARDS 4.1.1 Liquefaction Liquefaction is caused by a rapid increase in pore water pressure that reduces the effective stress between soil particles to near zero. Granular soil, which relies on interparticle friction for strength, is susceptible to liquefaction until the excess pore pressures can dissipate. In general, 40, [DESIGN= AW N`"V')ciA, a 5 RelatedNW 2 01:123120 ww r,. loose, saturated sand soil with low silt and clay content is the most susceptible to liquefaction. Silty soil with low plasticity is moderately susceptible to liquefaction under relatively higher levels of ground shaking. Since the soil beneath the groundwater level consists of very dense gravel, it is our opinion that the soil at the site is not susceptible to liquefaction. 4.1.2 Lateral Spreading Lateral spreading is a liquefaction-related seismic hazard and occurs on gently sloping or flat sites underlain by liquefiable sediment adjacent to an open face, such as a riverbank. Liquefied soil adjacent to an open face can flow toward the open face, resulting in lateral ground displacement. Since the soil at the site is not susceptible to liquefaction, it is our opinion that iFg lateral spreading is not a hazard at this site. 4.1.3 Fault Rupture There are no active faults mapped within approximately 1.4 miles of the site (USGS, 2020). art Therefore, it is our opinion that the risk of surface fault rupture beneath the site is low. 4.2 OTHER GEOLOGIC HAZARDS ww According to DOGAMI's online statewide geohazards viewer, there are no mapped landslides or flood hazards at the site (DOGAMI, 2018). 5.0 DESIGN RECOMMENDATIONS 5.1 FOUNDATION SUPPORT ww 5.1.1 General The preliminary grading plan shows that some building foundations will be at existing grades and other building foundations will be underlain by up to approximately 11 feet of fill. Based on the results of our explorations and analysis, we recommend that the proposed buildings be supported on spread footings that are underlain by firm native soil or structural fill. Footings should be sized using an allowable bearing pressure of 2,500 psf. This value may be increased 'o' by one-third for short-term loads such as wind and seismic forces. Footings should not be supported on undocumented fill. Also, new structural fill beneath footings should not be placed over soft undocumented fill. It may be necessary to over-excavate soft undocumented fill soil at some locations prior to footing construction or structural fill placement. Over-excavated areas beneath the new buildings should be backfilled with properly compacted structural fill. All footing subgrade should be evaluated by the project geotechnical engineer or their representative to evaluate bearing conditions. Observations should determine whether all loose or soft material, organic material, unsuitable fill, prior topsoil zones, and softened subgrades (if present) have been removed. Localized deepening of footing excavations may be required to penetrate unsuitable material. If native soil subgrade is soft, the subgrade should be recompacted or replaced with structural fill. Atv [ DESIGN= ,A„N V:5 ,-0 4110 6 RelatedNW 2 01:123120 40. irno The structural fill that is placed beneath new buildings to raise grades will result in settlement. Once the structural fill has been placed, we recommend that the construction of foundations, <.. floor slabs, and other structures be delayed until settlement monitoring data shows that tot settlement is complete. We recommend that isolated column and continuous wall footings have minimum widths of 24 and 18 inches, respectively. The bottom of exterior footings should be founded at least 18 inches below the lowest adjacent grade. Interior footings should be founded at least L12 inches below the bottom of the floor slab. 5.1.2 Lateral Resistance ' Lateral loads on footings can be resisted g by passive earth pressure on the sides of the footings 0,0 and by friction along the base of the footings. Our analysis indicates that the available passive k earth pressure is 350 pcf, modeled as an equivalent fluid pressure. The upper 12 inches of adjacent, unpaved areas should not be considered when calculating passive resistance. A coefficient of friction value equal to 0.30 may be used when calculating resistance to sliding for footings in direct contact with native soil. Footings in contact with imported crushed rock should aig be designed using a coefficient of friction value of 0.50. 5.1.3 Settlement As discussed in other sections of this report, we recommend that the construction of new foundations, floor slabs, and other structures be delayed until settlement monitoring data shows that settlement resulting from new structural fill to raise grades is complete. If this is done, we anticipate that footings supporting the anticipated design loads and constructed as recommended will experience less than 1 inch of total post-construction settlement and % inch r of differential settlement between similarly loaded adjacent footings. w. 5.2 SLABS ON GRADE We anticipate that the existing subgrade soil and new structural fill will generally provide "'"' adequate support for concrete slabs on grade. We recommend that the slab subgrade be evaluated during construction. If any loose undocumented fill or unsuitable soil is present tbeneath the floor slabs, the subgrade soil should be scarified and recompacted or over- excavated. A modulus of subgrade reaction of 120 pci can be used for design of the floor slabs, f provided the subgrade is prepared in accordance with the recommendations presented in this report. Post-construction settlement of slabs supporting the anticipated design loads and 4$11" constructed as recommended is anticipated to be less than 1 inch of total settlement and % inch of differential settlement. t 440 We recommend that floor slabs be supported on at least 6 inches of imported granular material to aid as a capillary break and to provide uniform support. The imported granular material should have a maximum particle size of 1% inches, should have less than 5 percent by dry weight passing the U.S. Standard No. 200 sieve, and should have at least two mechanically fractured faces. The imported granular material should be placed in one lift and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D1557. WADESIGW ' N V15 "V 7 RelatedNW 2 01:123120 it.► Vapor barriers beneath floor slabs are typically required by flooring manufactures to maintain the warranty on their products. In our experience, adequate performance of floor adhesives can be achieved by using a clean base rock(less than 5 percent fines) beneath the floor slab with no 60, vapor barrier. In fact, vapor barriers can frequently cause moisture problems by trapping water beneath the floor slab that is introduced during construction. If a vapor barrier is used, water should not be applied to the base rock prior to pouring the slab and the work should be completed during extended dry weather so that rainfall is not trapped on top of the vapor barrier. Selection and design of an appropriate vapor barrier, if needed, should be based on discussions among members of the design team. If requested, we can provide additional information to assist you with your decision. 5.3 SEISMIC DESIGN PARAMETERS Seismic design will be performed in accordance with ASCE 7-16, which is prescribed by the 2019 SOSSC and 2018 IBC. A Site Class D designation can be used to compute design levels of ground shaking. Per ASCE 7-16 Section 11.4.8, a site response analysis is required for this project unless the structural engineer determines that exception 2 in the code applies, which is based on the period of the buildings and the method of analysis used by the structural engineer. If a site response analysis is needed, we can perform this additional analysis. If a site response analysis is not needed, the seismic design parameters presented in Table 2 from ASCE 7-16 may be used for design. These parameters were obtained from USGS seismic design maps (SEAOC/OSHPD, 2020). Table 2. ASCE 7-16 Seismic Design Parameters Short Period 1 Second Period Parameter (Ts = 0.2 second) (T, = 1.0 second) Spectral Acceleration (MCE) SS = 0.867 g S, = 0.397 g r Site Classwog D Site Coefficient Fa= 1.153 F5= 1.903 Spectral Acceleration Parameters SMS= 1.000 g SM, = 0.755 g Design Spectral Acceleration Parameters SDS= 0.666 g So, = 0.504 g Spectral PGA 0.394 g Design Spectral PGA 0.263 g 4400 MCE, PGA Adjusted for Site Class Effects' PGAM = 0.475 g 1. From ASCE 7-16. Minimum PGA value to use when evaluating liquefaction and soil strength loss,as required by ASCE 7-16 Section 11.8.3. r.r 5.4 FILL-INDUCED SETTLEMENT The preliminary grading plan shows that up to 11 feet of new fill will placed to raise grades. The weight of this new fill will result in settlement of the existing soil. Once the structural fill has been placed, we recommend that the construction of new foundations, floor slabs, and other DESIGN ATM V'ScoanPxrov rw 8 RelatedNW-2-01:1231 20 ww structures be delayed until settlement monitoring data shows that settlement is complete. In addition, new fill should not be placed next to existing structures that could be damaged by settlement. MIN 5.4.1 Settlement Monitoring Settlement monitoring should be performed after fill placement is complete using survey markers or hubs installed in the fill areas. The survey hubs should be surveyed at least twice per week until it is determined that fill-induced settlement is complete. The survey hubs should be monitored using survey equipment with accuracy of 1/100t of a foot and referenced to a stationary datum established at least 100 feet from the edge of fill areas. We recommend installing at least four survey hubs at each building location. Additional survey hubs should be installed at the locations of new pavement, retaining walls, sidewalks, and other structures that tima could be damaged by settlement. Care must be taken during construction to avoid damaging the survey hubs. mow 5.4.2 Existing Structures. If new fill is placed next to existing structures, the weight of the new fill could cause damaging amounts of settlement beneath the existing structures. We note that the foundations of the existing buildings to the north of the site are within a few inches of the property line. We calculated the amount of settlement that could occur for various fill heights and summarized the results in Table 3. If requested, we can update these settlement estimates once a final grading plan has been developed. We recommend that the project structural engineer determine the amount of new settlement that the existing buildings can tolerate. The design team can then +w+- determine how closely fill can be safely placed next to existing structures. Table 3. Fill Settlement Estimates Fill Settlement Settlement at Distance from Edge of Fill (in Feet) to Height at Center Edge of Fill Achieve Less Settlement Than: (feet) of Fill (inches) 1.0 Inch 0.5 Inch 0.25 Inch 0.1 Inch (inches) 0 0.0 0.0 0.0 0.0 0.0 0.0 2 0.5 0.25 0.0 0.0 0.0 2.5 4 1.2 0.5 0.0 0.0 2.0 6.5 ,,, 6 2.1 0.8 0.0 1.4 3.0 10.0 8 2.8 1.2 0.7 2.2 4.8 12.5 10 3.5 1.7 1.7 3.7 6.8 17.5 400, 12 4.1 2.0 2.5 5.0 7.5 20.0 If it is necessary to place fill next to existing structures, other methods can be used to mitigate settlement damage, such as the use of lightweight fill or the installation of ground improvement. Upon request, we can provide additional recommendations for these mitigation methods. We also recommend conducting a pre-construction survey to document the condition of existing structures prior to placement of any fill. 40. DESIGN A N V 5 wtomo 9 RelatedNW-2-01:1 231 20 5.5 ON-SITE PAVEMENT RECOMMENDATIONS 5.5.1 Design Assumptions and Parameters We anticipate that on-site traffic will predominately consist of passenger vehicles with occasional taw delivery trucks and heavy vehicles, such as garbage trucks. Our pavement design recommendations assume the subgrade has been prepared in accordance with the "Site Preparation" and "Structural Fill" sections. Our pavement recommendations are based on the assumptions listed below. If any of these assumptions are incorrect, our office should be contacted with the appropriate information so that the pavement designs can be revised. • A resilient modulus value of 3,500 psi for native subgrade based on the soil type and DCP tests. • A pavement design life of 20 years. • Initial and terminal serviceability indices of 4.2 and 2.5, respectively. • Reliability of 75 percent and standard deviation of 0.5. • No growth. • Traffic will consist of 700 cars per day; 5 two-axle delivery trucks per day; and 1 three-axle delivery truck, garbage truck, or similarly heavy vehicles per day. • Construction traffic will not be allowed on new pavement. If construction traffic is to be allowed on the newly constructed pavement, our design pavement sections will need to be revised. 5.5.2 Recommended AC Pavement Design Sections (Post Construction) Our pavement design recommendations for the assumptions and loads provided above are presented in Table 4. Table 4. Recommended Standard Pavement Sections Iwo Pavement Use AC Thickness' Aggregate Base Thickness'•Z(inches) (inches) Drive Aisles -Automobile and Occasional Heavy Vehicle 3.0 10.0 Automobile Parking Only 3.0 8.0 1. All thicknesses are intended to be the minimum acceptable values. Additional thickness will be necessary if construction traffic is allowed on the pavement. 2. A subgrade geotextile fabric should be placed between the aggregate base and the subgrade. aw The subgrade should be unyielding or compacted to 95 percent of the maximum dry density, as determined by ASTM D1557. Areas that exhibit yielding or pumping should be repaired, as 4,0 described in this report. If silt or clay is present at the subgrade level, a subgrade geotextile fabric should be used to extend the life of the pavement by preventing fines from gradually migrating into the base rock. 5.5.3 Pavement Materials A submittal should be made for each pavement material prior to the start of paving operations. Each submittal should include the test information necessary to evaluate the degree to which the GEODESIGM. 1t5 WMPAmr 10 RelatedNW-2-01:1 23120 material's properties comply with the properties that were recommended or specified. The geotechnical engineer and other appropriate members of the design team should review each submittal. 5.5.3.1 Aggregate Base Imported granular material used as aggregate base for pavement should consist of 3/-, 1-, or '""' 1%-inch-minus material (depending on the application) and meet the requirements in OSSC 00641 (Aggregate Subbase, Base, and Shoulders). In addition, the aggregate should have less than 5 percent by dry weight passing the U.S. Standard No. 200 sieve. The aggregate base 440 should be compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D1557. vimo 5.5.3.2 AC The AC should be Level 2, %2-inch, dense ACP according to OSSC 00744 (Asphalt Concrete 4 Pavement) and compacted to 92 percent of the theoretical maximum density of the mix, as determined by AASHTO T 209. The minimum and maximum lift thicknesses are 2.0 and 3.0 inches, respectively, for Y2-inch ACP. Asphalt binder should be performance graded and conform to PG 64-22. AC paving should only occur when ground temperatures are 40 degrees Fahrenheit or warmer. 5.5.3.3 Subgrade Geotextile Fabric A subgrade geotextile fabric should be placed as a barrier between the subgrade and granular material. The geotextile should meet the specifications provided in OSSC 02320 (Geosynthetics) for separation geotextiles (Table 02320-4) and be installed in accordance with OSSC 00350 (Geosynthetic Installation). 5.6 RETAINING WALLS 5.6.1 Assumptions These retaining wall recommendations apply to permanent above-grade retaining walls. Our via retaining wall design recommendations are based on the following assumptions: (1)the walls consist of conventional, cantilevered retaining walls, (2)the walls are less than 10 feet in height, (3) drains are provided to prevent hydrostatic pressure from developing, and (4)the retained soil is level. Re-evaluation of our recommendations will be required if the retaining wall design criteria for the project varies from these assumptions. "`e 5.6.2 Wall Design Parameters For unrestrained retaining walls, an active equivalent fluid pressure of 35 pcf should be used for design. Where retaining walls are restrained from rotation prior to being backfilled, an at-rest equivalent fluid pressure of 55 pcf should be used for design. A superimposed seismic lateral force should be calculated based on a dynamic force of 7H2 pounds per linear foot of wall (where H is the height of the wall in feet). The load should be applied as a distributed load with the ifto centroid located at a distance of 0.6H above the base of the wall. If surcharges (e.g., retained slopes, building foundations, vehicles, terraced walls, etc.) are located within a horizontal distance from the back of a wall equal to the height of the wall, additional pressures will need to be accounted for in the wall design. Figure 3 presents re►DESIGN=_ RN comPANY 1 1 RelatedNW-2-01:123120 L additional pressures resulting from some common loading scenarios. Our office should be contacted for additional pressures resulting from alternate loading scenarios. We recommend a vertical live load of 250 psf be applied at the surface of the retained soil where the wall retains roadways. The base of the wall footing excavations should extend a minimum of 18 inches below the lowest adjacent grade. The wall footings should be designed in accordance with the guidelines in the "Foundation Support" section. At locations where there is a slope in front of the retaining wall, we recommend a minimum 5-foot-wide, horizontal bench be placed between the wall and the top of the slope. Sig 5.6.3 Wall Drainage and Backfill The above design parameters have been provided assuming that drains will be installed behind the walls to prevent buildup of hydrostatic pressures. Backfill material placed behind retaining walls and extending a horizontal distance of%H (where H is the height of the retaining wall) should consist of imported granular material meeting the requirements described in the "Structural Fill" section. Alternatively, the native soil can be used as backfill material, provided a minimum 2-foot-wide column of angular drain rock wrapped in a drainage geotextile is placed against the wall and the native soil can be adequately moisture conditioned for compaction. The rock column should extend from the perforated drainpipe or foundation drains to within approximately 1 foot of the ground surface. The angular drain rock should have a maximum particle size of 2 inches, should have less than 2 percent by dry weight passing the U.S. Standard No. 200 sieve, should have at least two mechanically fractured faces, and should be free of organic material and other unsuitable materials. Perforated collector pipes should be placed at the base of the granular backfill behind the walls. The pipe should be embedded in a minimum 2-foot-wide zone of angular drain rock wrapped in a drainage geotextile fabric. The collector pipes should discharge at an appropriate location away from the base of the wall. Unless measures are taken to prevent backflow into the drainage VMS system of the wall, the discharge pipe should not be tied directly into stormwater drain systems. Backfill should be placed and compacted as recommended for structural fill, with the exception of backfill placed immediately adjacent to walls. Backfill adjacent to walls should be compacted to a lesser standard to reduce the potential for compaction-induced earth pressures on the walls. Backfill located within a horizontal distance of 3 feet from the retaining walls should be compacted to approximately 90 percent of the maximum dry density, as determined by ASTM Dl 557. Backfill placed within 3 feet of the wall should be compacted in lifts less than 6 inches thick using hand-operated tamping equipment (such as a jumping jack or vibratory plate compactor). If flatwork (such as slabs, sidewalk, or pavement)will be placed adjacent to the wall, we recommend that the upper 2 feet of fill be compacted to 95 percent of the maximum dry density, as determined by ASTM D1557. Settlement of up to 1 percent of the wall height commonly occurs immediately adjacent to the wall as the wall rotates and develops active lateral earth pressures. Consequently, we recommend that construction of flatwork adjacent to retaining walls be postponed at least four weeks after construction, unless survey data indicates that settlement is complete prior to that time. •7DESIGN aN N I S � r. U 12 RelatedNW 2 Ol:123120 ww, rf L 5.7 PERMANENT SLOPES Permanent cut or fill slopes should not exceed a gradient of 2H:1 V, unless specifically evaluated for stability. Upslope buildings, access roads, and hardscapes should be set back a minimum of 5 feet from the crest of such slopes. Slopes should be planted with appropriate vegetation to provide protection against erosion as soon as possible after grading. Surface water runoff should be collected and directed away from slopes to prevent water from running down the face of the slope. I5.8 DRAINAGE 5.8.1 Surface The finished ground surface around buildings should be sloped away from foundations at a minimum 2 percent gradient for a distance of at least 5 feet. Pavement surfaces and open space areas should be sloped such that surface water runoff is collected and routed to suitable discharge points. Runoff water should not be directed to the top of slopes. 5.8.2 Subsurface 1 We recommend that foundation drains be installed around the perimeter of the buildings at locations where the finish floor elevation will be lower than adjacent grades. Foundation drains are not necessary at locations where the finish floor elevation will be above adjacent grades. We recommend that footing drains and roof downspouts or scuppers discharge to a solid pipe that ,,, carries the collected water to an appropriate stormwater system that is designed to prevent backflow. If drywells are used, we recommend that the top of the perforated drywell sections be at least 10 feet below adjacent enclosed spaces such as basements, elevator pits, etc. 5.8.3 Temporary During grading the contractor should be made responsible for temporary drainage of surface MO water as necessary to prevent standing water and/or erosion at the working surface. The contractor should keep all footing excavations and building pads free of water during rough and f; r finished grading of the building site. 6.0 CONSTRUCTION RECOMMENDATIONS 6, 6.1 SITE PREPARATION 6.1.1 Stripping and Grubbing Stripping and grubbing will be required to remove any grass, trees, and shrub roots that remain "°w after cuts are performed. Root material should be removed from all building, pavement, and structural fill areas. The actual stripping and grubbing depth should be based on field _" observations at the time of construction. Stripping and grubbing should extend at least 5 feet ".. beyond the limits of proposed building and pavement areas. Excavated roots should be transported off site for disposal or used as fill in landscaped areas. 6.1.2 Tilled Zone r An approximately 6-to 12-inch-thick layer of disturbed loose soil that we interpret as a tilled zone is present over most of the site. The tilled zone material consists of native silt; however, iiii dr r. raiDEsIcN 'Y S ate � -- 13 RelatedNW-2-01:1 231 20 i Ww i through years of cultivation, the tilled zone includes slightly higher organic contents and lower densities. When wet, the soil is likely to exhibit very low strength and generally does not provide adequate building or pavement subgrade support. Mil Within all proposed structural fill, pavement, and improvement areas; for a 5-foot margin beyond such areas; and where less than 12 inches of cut is required, we recommend that the top 6 to iii 12 inches of the stripped subgrade be scarified and re-compacted, cement amended, or removed and replaced, as recommended for structural fill. As discussed in the "Structural Fill" section, the 1 1, native silt can be sensitive to small changes in moisture content and will be difficult, if not impossible, to compact adequately during wet weather. Scarifying and re-compacting the soil will likely only be possible during extended dry periods and following moisture conditioning of the soil. Cement amendment is an option for conditioning the soil for use as structural fill ow during periods of wet weather or when drying the soil is not an option. f 6.1.3 Demolition 60 Demolition will be required on this project to remove existing footings, walls, slabs, utilities, basements, decks, pavement, and other similar improvements that may be found during construction. These existing elements should be completely removed from beneath new structures. Any monitoring wells or underground storage tanks on the property should be abandoned in accordance with state and local regulations prior to site redevelopment. �;, Excavations resulting from demolition of existing improvements should be backfilled with compacted structural fill as recommended in this report. The bottom of the excavations should expose firm subgrade. The sides of the temporary excavations should be cut into firm material II and sloped no steeper than 1%H:1 V. 6.1.4 Subgrade Evaluation tog A member of our geotechnical staff should observe all footing, floor slab, and hardscape subgrades after stripping and grubbing, excavation, scarifying and compaction (if applicable), and placement of structural fill have been completed to confirm that there are no areas of w" unsuitable or unstable soil. The subgrade should be evaluated using moisture-density testing, a hand probe, or proof rolling with a fully loaded dump truck (or similar heavy, rubber tire construction equipment). Soft, loose, or unsuitable soil found at the subgrade level should be 40, over-excavated and replaced with structural fill. 6.2 EXCAVATION "" 6.2.1 General Excavations will be required for construction of new foundations, retaining walls, stormwater facilities, utilities, and other improvements. Conventional earthmoving equipment in proper working condition should be capable of making the necessary excavations. We anticipate that temporary excavation sidewalls will generally stand vertical to a depth of approximately 4 feet, Lprovided groundwater seepage does not occur. r,- Excavations deeper than 4 feet will require shoring or should be sloped. Sloped excavations may be used to vertical depths of 10 feet BGS and should have side slopes no steeper than 11/2H:1 V, provided groundwater seepage does not occur. We recommend a minimum horizontal distance of 5 feet from the edge of existing improvements to the top of any temporary slope. All cut r [DESIGN= AN MY t5°WP ,�,.,, 14 RelatedNW-2-01:123120 VAN slopes should be protected from erosion by covering them during wet weather. If seepage, sloughing, or instability is observed, the slope should be flattened or shored. Shoring will be required where slopes are not possible. The contractor should be responsible for selecting the sio appropriate shoring system. Excavations should not be allowed to undermine adjacent improvements. If existing roads or structures are located near a proposed excavation, unsupported excavations can be maintained outside of a 1 H:1 V downward projection that starts 5 feet from the base of the existing elements. Excavations that must be inside of this zone should be supported by temporary or permanent shoring designed for moment resistance for the full height of the excavation, including kick-out for the full buried depth of the retaining system. While we have described certain approaches to performing excavations, it is the contractor's responsibility to select the excavation and dewatering methods, monitor the excavations for safety, and provide any shoring required to protect personnel and adjacent improvements. All 441111 excavations should be in accordance with applicable OSHA and state regulations. 6.2.2 Excavation Dewatering Excavations will be above the groundwater level. However, some perched water could still seep into the site excavations, especially after periods of heavy rain. We anticipate that dewatering methods consisting of pumping water from excavation sumps will generally be adequate. If possible, we recommend that construction be scheduled for the dry season. Water generated during dewatering operations should be treated, if necessary, and pumped to a suitable disposal 460 point. Where groundwater seepage occurs in excavations, we recommend placing at least 1 foot of stabilization material at the base of the excavations. The stabilization material should consist of 4- or 6-inch-minus pit- or quarry-run rock, crushed rock, or crushed gravel and sand. The material should have a maximum particle size of 6 inches, should have less than 5 percent by dry weight passing the U.S. Standard No. 4 sieve, and should have at least two mechanically fractured faces. The material should be free of organic material and other deleterious materials. We note that these recommendations are for guidance only. Dewatering of excavations is the sole responsibility of the contractor, as the contractor is in the best position to select the appropriate system based on their means and methods. 6.3 STRUCTURAL FILL Structural fill includes fill placed beneath foundations, floor slabs, hardscapes, and other structures. Structural fill should generally consist of particles no larger than 3 inches in diameter and should be free of organic material and other deleterious materials. Recommendations for suitable fill material are provided in the following sections. 6.3.1 On-Site Soil The on-site fine-grained soil will be suitable for use as structural fill only if it can be moisture conditioned. Based on our experience, this soil will be sensitive to small changes in moisture content and may be difficult, if not impossible, to compact adequately during wet weather or WOW GEODESIGN? -Nf 5trAaunav 15 RelatedNW-2-01:1 231 20 41W «a, when the moisture content is more than a few percentage points above optimum. The soil may require extensive drying before it can be used as structural fill. The on-site fine-grained soil should be placed in lifts with a maximum uncompacted thickness of 8 to 12 inches and compacted to not less than 92 percent of the material's maximum dry density, as determined by ASTM D1557. We recommend using imported granular material for structural fill if the moisture content of the on-site soil cannot be reduced. 6.3.2 Imported Granular Material Imported granular material should be pit- or quarry-run rock, crushed rock, or crushed gravel and sand that is fairly well graded between coarse and fine and has less than 5 percent by dry weight passing the U.S. Standard No. 200 sieve. All granular material must be durable such that there is no degradation of the material during and after installation as structural fill. The material should be placed in lifts with a maximum uncompacted thickness of 12 inches and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D1557. During the wet season or when wet subgrade conditions exist, the initial lift should have a maximum thickness of 18 inches and should be compacted by rolling with a smooth-drum, non-vibratory roller. 6.3.3 Recycled Concrete Recycled concrete can be used for structural fill, provided the concrete is broken to a maximum particle size of 3 inches. This material must be durable such that there is no degradation of the material during and after installation as structural fill. Recycled concrete can be used as trench backfill if it meets the size requirements for that application and the requirements for imported granular material. The material should be placed in lifts with a maximum uncompacted thickness of 12 inches and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D1557. 6.3.4 Trench Backfill Material City of Tigard or Washington County trench backfill requirements should be followed for any public utilities that are installed. Our trench backfill recommendations for private utilities are provided below. Trench backfill for the utility pipe base and pipe zone should consist of durable, well-graded, granular material that has a maximum particle size of 1 inch, has less than 5 percent by dry weight passing the U.S. Standard No. 200 sieve, and contains no organic or other deleterious "' materials. Backfill above the pipe zone should meet the requirements above, except that the maximum particle size may be increased to 1Y2 inches. Backfill for the pipe base and within the pipe zone should be placed in maximum 12-inch-thick lifts and compacted to not less than 90 percent of the maximum dry density, as determined by ASTM D1557, or as recommended by the pipe manufacturer. Backfill above the pipe zone should be placed in maximum 12-inch-thick lifts and compacted to not less than 92 percent of the maximum dry density, as determined by ASTM Dl 557. Trench backfill located within 2 feet of finish subgrade elevation should be placed in maximum 12-inch-thick lifts and compacted to eat GEODESIGN'i AN v,J•ccM"""°'" 16 RelatedNW-2-01:1231 20 I. �. . y< %r r" 6 f. iii. not less than 95 percent of the maximum dry density, as determined by ASTM D1557. Outside of structural areas, trench backfill material should be compacted to at least 90 percent of the 8 maximum dry density, as determined by ASTM Dl 557. 6.3.5 Stabilization Material Stabilization material used in staging or haul road areas or in trenches should consist of 4- or N"' 6-inch-minus pit- or quarry-run rock, crushed rock, or crushed gravel and sand. The material f. should have a maximum particle size of 6 inches, should have less than 5 percent by dry weight passing the U.S. Standard No. 4 sieve, and should have at least two mechanically fractured faces. The material should be free of organic material and other deleterious materials. Stabilization material should be placed in lifts between 12 and 24 inches thick and compacted to a well-keyed, firm condition. ailli 6.3.6 Cement Amending As an alternative to the use of imported granular material for wet weather structural fill, an experienced contractor may be able to amend the on-site soil with portland cement to obtain suitable support properties. Successful use of soil amendment depends on the use of correct mixing techniques, soil moisture content, and amendment quantities. Specific recommendations based on exposed site conditions for soil amending can be provided if ,,, necessary. However, for preliminary design purposes, we recommend a target strength for cement-amended subgrade for building and pavement subbase (below aggregate base) soil of ` 100 psi. The amount of cement used to achieve this target generally varies with moisture diitO content and soil type. It is difficult to predict field performance of soil to cement amendment due to variability in soil response, and we recommend laboratory testing to confirm expectations. itio For building and pavement subbase, we recommend assuming a minimum cement ratio of 6 percent (by dry weight). If organic material is present or the soil moistures are in excess of 30 percent, a cement ratio of 7 to 8 percent may be needed. The amount of cement added to the soil may need to be adjusted based on field observations and performance. WA A minimum curing of four days is required between amendment and construction traffic access. Consecutive lifts of fill may be amended immediately after the previous lift has been amended 1 and compacted (e.g., the four-day wait period does not apply). Construction traffic should not be allowed on unprotected, cement-amended subgrade. To protect the cement-amended surfaces from abrasion or damage, the finished surface should be covered with 4 to 6 inches of imported granular material. i Amendment depths for building/pavement, haul roads, and staging areas are typically on the order of 12, 16, and 12 inches, respectively. The actual thickness of the amended material and imported granular material for haul roads and staging areas will depend on the anticipated traffic, as well as the contractor's means and methods and, accordingly, should be the contractor's responsibility. i . Portland cement-amended soil is hard and has low permeability. This soil does not drain well and it is not suitable for planting. Future planted areas should not be cement amended, if practical, or accommodations should be made for drainage and planting. Moreover, cement MICADESIGW AN V 5` °""" 17 RelatedNW-2-01:1 231 20 W IOW Miii amending soil within building areas must be done carefully to avoid trapping water under floor slabs. We should be contacted if this approach is considered. Cement amendment should not be used if runoff during construction cannot be directed away from wetlands (if present). It is not possible to amend soil during heavy or continuous rainfall. Cement amending should not be performed if the ground temperature is less than 40 degrees. 111 6.4 EROSION CONTROL The on-site soil is susceptible to erosion. Consequently, we recommend that slopes be covered 1 with an appropriate erosion control product if construction occurs during periods of wet weather. We recommend that all slope surfaces be planted as soon as practical to minimize erosion. ii, Surface water runoff should be collected and directed away from slopes to prevent water from running down the slope face. Erosion control measures such as straw bales, sediment fences, and temporary detention and settling basins should be used in accordance with local and state ordinances. 6.5 WET WEATHER CONSTRUCTION Trafficability of soil at the ground surface may be difficult during extended wet periods or when the moisture content of the surface soil is more than a few percentage points above optimum. If not carefully executed, earthwork activities can create extensive soft areas, resulting in 6 significant repair costs. When the subgrade is wet of optimum, site preparation may need to be accomplished using track-mounted equipment loading into trucks supported on granular haul roads or working blankets. Based on our experience, at least 12 inches of granular material are typically required for light staging areas and at least 18 inches of granular material for haul roads subject to repeated equipment traffic. We typically recommend that imported granular material for haul roads and working blankets consist of durable crushed rock that is well graded and has less than 8 percent by dry weight passing the U.S. Standard No. 200 sieve. Where silt or clay is exposed at the ground surface, the performance of haul roads can typically be improved by placing a w"' geotextile on the subgrade before placing the granular material. The granular material should be placed in a single lift and the surface compacted until well keyed. Although we have ', presented typical recommendations for haul road and working blankets, the actual thickness and """' material should be determined by the contractor based on their sequencing of the project and the type and frequency of construction equipment. The base rock thickness for building areas is intended to support post-construction design loads and will not support construction traffic "`" when the subgrade soil is wet. If construction is planned for periods when the subgrade soil is wet, an increased thickness of base rock will be required. 7.0 OBSERVATION OF CONSTRUCTION Satisfactory foundation and earthwork performance depends to a large degree on the quality of iso construction. Sufficient observation of the contractor's activities is a key part of determining that the work is completed in accordance with the construction drawings and specifications. 1 Subsurface conditions observed during construction should be compared with those encountered during the subsurface exploration. Recognition of changed conditions often MIDESIGI!? AN N T'`5mow, 18 RelatedNW-2-01:1 231 20 requires experience; therefore, qualified personnel should visit the site with sufficient frequency to detect if subsurface conditions change significantly from those anticipated. We recommend that GeoDesign be retained to observe earthwork activities. We anticipate this will consist of evaluating foundation, floor slab, and pavement subgrade; observing the placement of structural fill and repair of soft subgrade areas, paving installation, retaining wall construction; and performing laboratory compaction and field moisture-density tests. 8.0 LIMITATIONS We have prepared this report for use by Related Northwest and their design and construction Iteams for the proposed project. The data and report can be used for bidding or estimating purposes, but our report, conclusions, and interpretations should not be construed as warranty of the subsurface conditions and are not applicable to other sites. Soil explorations indicate soil conditions only at specific locations and only to the depths penetrated. They do not necessarily reflect soil strata or water level variations that may exist between exploration locations. If subsurface conditions differing from those described are noted during the course of excavation and construction, re-evaluation will be necessary. The site development plans and design details were preliminary at the time this report was prepared. When the design has been finalized and if there are changes in the site grades or location, configuration, design loads, or type of construction, the conclusions and recommendations presented may not be applicable. If design changes are made, we request that we be retained to review our conclusions and recommendations and to provide a written verification or modification. The scope of our services does not include services related to construction safety precautions, and our recommendations are not intended to direct the contractor's methods, techniques, sequences, or procedures, except as specifically described in this report for consideration in design. Within the limitations of scope, schedule, and budget, our services have been executed in accordance with generally accepted practices in this area at the time this report was prepared. No warranty or other conditions, express or implied, should be understood. ♦ ♦ ♦ I I I DESIGN= A N V 5 ,MP�� ,�,. 19 RelatedNW-2-01:123120 We appreciate the opportunity to be of continued service to you. Please call if you have questions concerning this report or if we can provide additional services. iiii Sincerely, GeoDesign, Inc. sO PRO r Ryan T. Lawrence, P.E. Associate EngineerAr EG IV'P 7 y t A, skk‘' iii Brett A. Shipton, P.E., G.E. EXPIRES` 6/30/22 Principal Engineer L I I I I I I I P , EASIDESIGNY A"IT5"4AA Y 20 RelatedNW-2-01:123120 6111* REFERENCES ASCE, 2016. Minimum Design Loads and Associated Criteria for Buildings and Other Structures. Publication ASCE 7-16. Atwater, B. F., and E. Hemphill-Haley, 1997. Recurrence intervals for great earthquakes of the past 3500 years at northeastern Willapa Bay, Washington: U.S. Geological Survey Professional Paper 1576, 108 pp. Burns, Scott, 1998. Geologic and physiographic provinces of Oregon. p 3-14 in Scott Burns, editor, Environmental, Groundwater and Engineering Geology:Applications from Oregon. Association of Engineering Geologists. Special Publication 11, 689 p. Goldfinger, C., C.H. Nelson, and J.E.Johnson, 2003. Holocene earthquake records from the Cascadia subduction zone and northern San Andreas Fault based on precise dating of offshore turbidities: Annual Reviews Earth Planetary Science v. 31, pp. 555-577. DOGAMI, 2018. Oregon HazVu:Statewide Geohazards Viewer. Obtained from website: http://www.oregongeology.org/hazvu/index.htm. Last updated March 13, 2018. Accessed on December 14, 2020. Ma, Lina, Madin, Ian P., Duplantis, Serin, Williams, KendraJ., 2012. Lidar-Based Surficial Geologic Map of the Greater Portland Area; Clackamas, Columbia, Marin, Multnomah, Washington, and Yamhill Counties, Oregon and Clark County, Washington. Oregon Department of Geology and Mineral Industries. Open File Report 0-12-02. Scale 1:63,360. aft Orr, E.L. and Orr, W.N., 1999. Geology of Oregon. Kendall/Hunt Publishing, Iowa: 254 p. Satake, K., K. Shimazaki, Y. Tsuji, and K. Ueda, 1996. Time and size of a giant earthquake in Cascadia inferred from Japanese tsunami records of January 1700: Nature, v. 379, pp. 146-149. SEAOC/OSHPD, 2020. Seismic Design Maps. Accessed from website: https://seismicmaps.org/. 4,0 Accessed on June 2, 2020. Schlicker, H.G. and Deacon, R.J., 1967. Geology and Surficial Deposits of the Tualatin Valley Region, Oregon. Oregon Department of Geology and Mineral Industries. Bulletin 60. Scale 1:48,000. USGS, 2020. Faults; Quaternary Fault and Fold Database of the United States. 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O O I'' M T O —N o t^Q O O71 'aft r m m OM G EO DES I G N= RELATEDNW-2-01 SITE PLAN ANNIVIS COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE 2 TIGARD,OR t Printed By:aday I Print Date: 12/29/2020 4:39:54 PM File Name:):\M-R\RelatedNW\RelatedNW-2\RelatedNW-2-01\Figures\CAD\RelatedNW-2-01-det-SILEP.dwg I Layout:FIGURE 3 X=mH X=mH RETAINING GROUND SURFACE WALL OR GROUND GROUND SHORING SURFACE 'POINT LOAD,Qp SURFACE 1LINE LOAD,QL 4 STRIP LOAD, 0 0 1 41 MEM RETAINING *A I I WALL OR .i NJ N SHORING Ta -� N I I — = FOR m<0.4= RETAINING FOR m<0.4= lirah=y (IS-SIN COS 2a) a _ 0.28 n2 WALL OR a Q QL 0.2 n a 3.14 ah h H2 (0.16+n2)3 SHORING —� h h H (0.1 )2 h „� �,/\ \,/ (�IN RADIANS) /\�J/ FOR m>0.4= \///�\/i, FOR m>0.4= \//\�\�i� — '�\>�i%��%\\\/,\\/., ah = 1.77m 22n3 \\/ //�\/\\\jam\\j\ ah =QL 1.28m2 n y�\' //�/\\///��� //\few// H (m +n ) /:t\�5��// H (m 2+n2)Z \//<4,„// EXCAVATION BASE EXCAVATION BASE EXCAVATION BASE RETAINING WALL OR SHORING LINE LOAD PARALLEL TO WALL STRIP LOAD PARALLEL TO WALL 2 II x eh il dh =ah COS (1.14') r DISTRIBUTION OF HORIZONTAL PRESSURES NOT TO SCALE VERTICAL POINT LOAD NOTES: 1. FIGURE SHOULD BE USED IN CONJUNCTION WITH REPORT TEXT. 2. THESE GUIDELINES APPLY TO RIGID WALLS WITH POISSON'S RATIO ASSUMED TO BE 0.5 FOR BACKFILL MATERIALS. 3. LATERAL PRESSURES FROM ANY COMBINATION OF ABOVE LOADS MAY BE DETERMINED BY THE PRINCIPLE OF SUPERPOSITION. G EDDESIGN? RELATEDNW-2-01 SURCHARGE-INDUCED LATERAL EARTH PRESSURES AN COMPANY DECEMBER 2020 NIV15 TERRACE GLENN APARTMENTS FIGURE 3 TIGARD, OR LLI aelli ant an APPENDIX A FIELD EXPLORATIONS GENERAL We conducted a subsurface exploration program that consisted of drilling 11 borings (B-1 through B-11) at the approximate locations shown on Figure 2. The borings were drilled to depths between 0.9 foot and 22.7 feet BGS using solid-stem auger drilling methods. Drilling services were performed by Dan J. Fischer Excavating, Inc. of Forest Grove, Oregon, on December 2 and 18, 2020. The explorations were observed and logged by members of our geology staff. We collected representative samples of the various soil encountered in the explorations for visual classification and laboratory testing. The exploration logs are presented in this appendix. The exploration locations were marked in the field relative to visual site features. The exploration locations should be considered accurate only to the degree implied by the methods used. The exploration elevations were estimated using a topographic map of the site. 6�w SOIL SAMPLING We collected soil samples from the borings using the following methods: atoor • SPTs were performed in general conformance with ASTM D1586. The sampler was driven with a 140-pound automatic trip hammer free-falling 30 inches. The number of blows required to drive the sampler 1 foot, or as otherwise indicated, into the soil is shown adjacent to the sample symbols on the exploration logs. Disturbed samples were collected from the split barrel for subsequent classification and index testing. • Shelby tube samples were collected in general accordance with ASTM D1587. The 2.5-foot long, 3-inch-diameter, thin-walled, seamless steel tubes were pushed into the soil in one continuous stroke. Each tube, together with the encased soil, was removed from the ground *a' and sealed. Sampling methods and intervals are shown on the exploration logs. The hammer used to conduct the SPTs was lifted using a rope and cathead system. The hammer was raised using two wraps of the rope around the cathead to conduct the SPTs. SOIL CLASSIFICATION The soil samples were classified in accordance with the "Exploration Key" (Table A-1)and "Soil Classification System" (Table A-2), which are presented in this appendix. The exploration logs `i" indicate the depths at which the soils or their characteristics change, although the change could be gradual. A horizontal line between soil types indicates an observed (visual or digging action) change. If the change occurred between sample locations and was not observed or obvious, the (rw depth was interpreted and the change is indicated using a dashed line. Classifications are shown on the exploration logs. otar ram. ►'""'���DESIGN '"N V'5 moo"'' A-1 RelatedNW-2-01:1 231 20 r LABORATORY TESTING We visually examined soil samples collected from the explorations to confirm field classifications. We also performed the following laboratory testing. MOISTURE CONTENT We determined the natural moisture content of select soil samples in general accordance with ASTM D2216. The natural moisture content is the ratio of the weight of the water tosoil g in a test sample and is expressed as a percentage. The test results are presented in this appendix. a�w PARTICLE-SIZE ANALYSIS We completed particle-size analysis on select soil samples in general accordance with ASTM D1140. The percent fines is the ratio of the dry weight of the material passing the U.S. Standard No. 200 sieve to the dry weight of the overall sample. The test results are presented in this appendix. ATTERBERG LIMITS TEST „ We determined the Atterberg limits of a select soil sample in general accordance with ASTM D4318. Atterberg limits include the liquid limit, plastic limit, and the plasticity index of soil. These index properties are used to classify soil and for correlation with other engineering properties of soil. The test results are presented in this appendix. CONSOLIDATION TESTING Consolidation testing was performed on a select soil sample in general accordance with ASTM D2435. This test determines the magnitude and rate of consolidation of soil when it is restrained laterally and drained axially while subjected to incrementally applied controlled-stress loading. The test results are used to estimate the magnitude and rate of settlement of the site soil under a specific increase in effective stress. The test results are presented in this appendix. art + DESIGNZ """N 1 5°A"°"'�'� A-2 RelatedNW-2-01:123120 ., «....«...............n.is.:.r.er+...•,.E,,,l,rvuiw[N)M""eNlw(N rrsHsre, ir.tae,s.U..rv4iulfistlroa3ifflf3f#fHJllJdlll#eN717NbiR!!V%vJNru.t...l. ......... .,.....,. .....,•,a >r.,.... ,..r.r.r. u..a». ,.f.....,» t.rvirvs w..r,. SYMBOL SAMPLING DESCRIPTION Location of sample collected in general accordance with ASTM D1 586 using Standard Penetration Test with recovery 1!. Location of sample collected using thin-wall Shelby tube or Geoprobe® sampler in general accordance with ASTM D1587 with recovery Location of sample collected using Dames & Moore sampler and 300-pound hammer or pushed with recovery 1E Location of sample collected using Dames & Moore sampler and 140 ound hammer or pushed p with recovery 1 Location of sample collected using 3-inch-O.D. California split-spoon sampler and 140-pound hammer with recovery MLocation of grab sample Graphic Log of Soil and Rock Types ,° ;, Observed contact between soil or Rock coring interval , ,:s- rock units (at depth indicated) \/ Water level during drilling Inferred contact between soil or rock units (at approximate depths indicated) 1 Water level taken on date shown -: i GEOTECHNICAL TESTING EXPLANATIONS ATT Atterberg Limits P Pushed Sample CBR California Bearing Ratio PP Pocket Penetrometer (< CON Consolidation P200 Percent Passing U.S. Standard No. 200 DD Dry Density Sieve DS Direct Shear RES Resilient Modulus HYD Hydrometer Gradation SIEV Sieve Gradation MC Moisture Content TOR Torvane c MD Moisture-Density Relationship UC Unconfined Compressive Strength „., NP Non-Plastic VS Vane Shear OC Organic Content kPa Kilopascal f. ENVIRONMENTAL TESTING EXPLANATIONS CA Sample Submitted for Chemical Analysis ND Not Detected ,".. P Pushed Sample NS No Visible Sheen PID Photoionization Detector Headspace SS Slight Sheen Analysis MS Moderate Sheen 4. ppm Parts per Million HS Heavy Sheen MDES{GN? EXPLORATION KEY TABLE A-1 AN N i V.5 COMPANY RELATIVE DENSITY- COARSE-GRAINED SOIL Relative Density Standard Penetration Dames& Moore Sampler Dames& Moore Sampler Resistance (140-pound hammer) (300-pound hammer) — 't., Very Loose 0-4 0 - 11 0-4 — Loose 4 - 10 1 1 - 26 4- 10 , Medium Dense 10- 30 26- 74 10- 30 Dense 30 - 50 74- 120 30-47 Very Dense More than 50 More than 120 More than 47 CONSISTENCY - FINE-GRAINED SOIL Standard Dames&Moore Dames& Moore Unconfined Consistency Penetration Sampler Sampler Compressive Strength Resistance (140-pound hammer) (300-pound hammer) (tsfl Very Soft Less than 2 Less than 3 Less than 2 Less than 0.25 Soft 2 -4 3 -6 2 - 5 0.25 - 0.50 Medium Stiff 4- 8 6- 12 _ 5 -9 0.50 - 1.0 Stiff 8- 15 12 - 25 9 - 19 1.0- 2.0 Very Stiff 15 - 30 25 -65 19 - 31 2.0-4.0 Hard More than 30 More than 65 More than 31 More than 4.0 PRIMARY SOIL DIVISIONS GROUP SYMBOL GROUP NAME CLEAN GRAVEL GW or GP GRAVEL GRAVEL (< 5%fines) (more than 50%of GRAVEL WITH FINES GW-GM or GP-GM GRAVEL with silt coarse fraction ( - 5%and <_ 12%fines) GW-GC or GP-GC _ GRAVEL with clay COARSE- retained on GRAVEL WITH FINES GM silty GRAVEL ,.,r, GRAINED SOIL No. 4 sieve) (> 12%fines) GC clayey GRAVEL GC-GM silty, clayey GRAVEL (more than 50% CLEAN SAND retained on SAND (<5%fines) SW or SP SAND No. 200 sieve) (50%or more of SAND WITH FINES SW-SM or SP-SM SAND with silt (>_ 5%and <_ 12%fines) SW-SC or SP-SC SAND with clay fraction ,,,„ passing SAND WITH FINES SM silty SAND No. 4 sieve) SC clayey SAND (> 12%fines) SC-SM silty, clayey SAND ML SILT L FINE-GRAINED CL CLAY SOIL Liquid limit less than 50 CL-ML silty CLAY (50%or more SILT AND CLAY OL ORGANIC SILT or ORGANIC CLAY passing MH SILT f No. 200 sieve) Liquid limit 50 or greater CH CLAY OH ORGANIC SILT or ORGANIC CLAY HIGHLY ORGANIC SOIL PT PEAT MOISTURE01 CLASSIFICATION ADDITIONAL CONSTITUENTS Secondary granular components or other materials Term Field Test such as organics, man-made debris,etc. Silt and Clay In: Sand and Gravel In: ,,.,, very low moisture, Percent Fine-Grained Coarse- Percent Fine-Grained Coarse- dry dry to touch Soil Grained Soil Soil Grained Soil moist damp,without < 5 trace trace < 5 trace trace visible moisture 5 - 12 minor with 5 - 15 minor minor wet visible free water, > 12 some silty/clayey 15 - 30 with with usually saturated > 30 sandy/gravelly Indicate ihNts 5, EO DESIGNz SOIL CLASSIFICATION SYSTEM TABLE A-2 AN N V 5 COMPANY Wiw u z INSTALLATION AND O 2 u w ♦BLOW COUNT DEPTH Q eL z 0 •MOISTURE CONTENT% COMMENTS FEET a- -`4 MATERIAL DESCRIPTION )w H g Q w 0 w < inT1 RQD% 1771 CORE REC% Um u 252.0 ~ 0 50 100 -o.o _ ASPHALT CONCRETE (2.0 inches). 251.8 0.2 . \AGGREGATE BASE (4.0 inches). f 251.5 0.5 Stiff, light brown SILT with sand (ML); moist, silt is non-plastic to low 2.5 plasticity. I] 1 1 PP=1.75 tsf PP ♦ ifito 5.0 • PP 11 14 Infiltration test at 5.0 feet. M1 P200 P200=84% PP=2.0 tsf 7.5 very stiff at 7.5 feet Aim 17 PP A PP=2.0 tsf 10.0 stiff; wet at 10.0 feet 13 PP=2.25 tsf PP A ilio 12.5 238.0 miry % Stiff, red-brown CLAY (CL), trace sand; - 14.0 15.0 moist, clay has medium to high plasticity. i. PP A3 • PP=2.25 tsf E • rn c 17.5 v Y Mili O ill M 233.0 - . Very dense, red-brown GRAVEL with silt 19.0 °0� and sand (GP-GM); wet, gravel is fine to w 20.0 p.,; Q o p coarse and subrounded, sand is fine to111 42-50/5� 0* 0 \coarse (decomposed basalt). �_231.1 z 20.9 R Exploration terminated at a depth of 20.9 feet due to refusal on gravel. - 22.5 o"" u. SPT completed using two wraps with a > cathead. z O u Moi u 25.0 m 0 milt z 27.5 0 W H J W c Mito W u d 30.0 ..6, 0 50 100 a DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:L.Gose COMPLETED:12/02/20 z p BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:6 1/4 inches and 4 inches L, fir 9u DESIGN RELATEDNW-2-U1 BORING B-1 z Ce COMPANY "N N ( 5 DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A-1 TIGARD,OR rww *II U Z INSTALLATION AND 2 0 2 U UJ ♦BLOW COUNT DEPTH v Q a Z - •MOISTURE CONTENT% COMMENTS FEET a MATERIAL DESCRIPTION >w - 2 .< uJ 0 w . fliT] RQD% �CORE REC% *0 U 254.0 ~ 0 50 100 0.0 Medium stiff, brown SILT with sand (ML); moist, silt has low plasticity, sand is fine (2.75-inch-thick root zone). 2.5- PP PP=2.5 tsf rWr - 5.0- stiff at 5.0 feet 10 Infiltration test at 5.0 feet. 1p - P200 A • P200=84% Stopped drilling for the day (12/2/20)at 6.5 feet. _ lz/la/2°' Resumed drilling on err 7.5 light brown, minor sand at 7.5 feet 12 A 10.0- medium stiff to stiff, with sand; moist 8 Appears to be a zone of to wet, stratified beds of sandy SILT ` perched water at 10.0 feet. - (wet) at 10.0 feet filli 12.5- All 239.0 15.07,-Stiff, dark brown-red CLAY (CL), trace 15.0 sand; moist, clay has medium to high 11 `° Ow plasticity. 0 77 17.5 v F- / 236.0 ro `' o Very dense, brown-orange to gray, silty 180 Driller Comment: harder, 1aW C :, but smooth drilling at 18.0 v SAND (SM), minor clay, trace gravel; wet feet. _':... (decomposed basalt). o So.o Y F `° o moist at 21.0 feet 111 .. ' 231.5 wit u 22.5 Very dense, gray GRAVEL(GP); moist to 22.5 m sa2� 231.3 Drill rig chatter at 22.5 feet. > _ \wet (decomposed basalt). 22.7 Zi - Exploration terminated at a depth of 0 - 22.7 feet due to refusal on gravel. r- 25.0- SPT completed using two wraps with a - cathead. N - z 27.5- 0 w - 1- a J d - W u - d 30.0 z 0 50 100 d iiiilik DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:L.Gose/J.Heidgerken COMPLETED:12/18/20 z p BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:6 inches and 4 inches u far. ° MDESIGN� RELATEDNW 2 O1 BORING B-2 ° AN fl 5can'Pnr1Y DECEMBER 2020 TERRACE GLENN APARTMENTS TIGARD,OR FIGURE A 2 fire - ,,,,,, u z° 0= U w ♦BLOW COUNT INSTALLATION AND DEPTH ¢a z a •MOISTURE CONTENT% COMMENTS FEET a MATERIAL DESCRIPTION ]w N g z J 0 tf; . RQD% CORE REC% woo u w I- 0 50 100 -0.0 246.0 -r- Soft, dark brown SILT(ML), minor 245.5 Isand; moist - FILL. 0.5 Medium dense, brown GRAVEL with silt 244.5 Atatr and sand (GP-GM); moist, gravel is fine 1.5 2.5- and angular to subrounded, sand is fine to coarse FILL. Attempted Shelby at 2.5 PP ♦1 • feet;too stiff. - Stiff, brown SILT (ML), trace sand; moist, PP=1.25 tsf "'r silt has low plasticity (6-inch-thick tilled zone, 4-inch-thick root zone). 5.0- - 14 PP=2.0tsf 411Yr - PP 11 A 7.5 very stiff at 7.5 feet 1$ PP PP=2.5 tsf Aim* 10.0- stiff; moist to wet at 10.0 feet 13 PP=2.5 tsf PP 11 A Am 12.5- DD=95 pcf DD p • = wrr CON = 75.0�j 17. _231.0 - • o, Medium stiff to stiff, brown-red CLAY 1 5'0 PP=2.0 tsf (CL), trace sand; moist, clay has medium PP 8 • PL-17% 6 4_,_ „,iw to high plasticity. _ _229.0 co O /c Very dense, brown GRAVEL with silt and '7•0 Driller Comment: tougher 1 7.5=p drilling and chatter at 17.0 i:v sand (GP-GM); wet, gravel is fine to feet. o DO d coarse and subrounded, silt has low _. plasticity, sand is fine to coarse �o (decomposed basalt). Li 20.0-.�I 'R 225.9 0 50/1'A wwr o Exploration terminated at a depth of 201 20.1 feet due to refusal on gravel. z Fe - SPT completed using two wraps with a i_ 22.5- cathead. MO o u z a u ern u 25.0- m o - J N - z 27.5- 0 F- - g - cc MAO w u a 30.0 z 0 50 100 a DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:L.Gose COMPLETED:12/02/20 z p BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:4 inches u iw ° D�CI�^►*�z RELATEDNW-2-01 BORING B-3 z JVi�I AN N V 5 COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A-3 TIGARD,OR +ww i,,, u z INSTALLATION AND O S u w •♦BLOW COUNT DEPTH 1-1— a z a •MOISTURE CONTENT% COMMENTS FEET a MATERIAL DESCRIPTION w o N g z J w < RQD% CORE REC% H u 236.0 0 50 100 0.0 Very stiff, light brown SILT(ML), minor sand; moist, silt has low plasticity (6- inch-thick tilled zone, 4-inch-thick root mow _ zone). 2.5— 24 PP=2.0 tsf PP 11 ` its 5.0- - PP `6• Infiltration test at 5.0 feet. illli — P200II P200=86% PP=2.0 tsf 7.5— rm - stiff; moist to wet at 7.5 feet 14• PP=1.5 tsf PP 11 iiii 10.0�� Stiff, red-brown CLAY (CL), trace sand; —210 0 / moist, clay has medium to high pp11 r PP=1.5 tsf plasticity, iiii 12.5 tlrr 15.0 '� . medium stiff; moist at 15.0 feet 6 m PP F ` • PP=1.Otsf c iiiirtul 17.5�/ Ln Y W Ms o / _217.5 ..V q'.c Very dense, red-brown GRAVEL with silt 18 5 Driller Comment: tougher m —:(.`- drilling and light chatter at -. _ ob.� and sand (GP-GM); wet, gravel is fine to 18.5 feet. w 200-0,' coarse and subrounded, sand is fine to 1-- __:(3 coarse (decomposed basalt). 62 fifyr Qp ,:os A 1— ,Q�? 11 z .0.:..o rc -i v. ✓ 22.5—'P. 21 3.3 50/2.. WM. o \trace clay at 22.5 feet ,r 22.7 > — Exploration terminated at a depth of 0 - 22.7 feet due to refusal on gravel. u I+w c7 25.0— SPT completed using two wraps with a - cathead. - a* N z 27.5— u - g w 4iir w - u - • 30.0 cc 0 50 100 Lu DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:L.Gose COMPLETED:12/02/20 z p BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:6 1/4 inches and 4 inches u ire °• WODESIGNU = RELATEDNW-2-01 BORING B-4 z re AN N Y 5COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A-4 TIGARD,OR dri` INSTALLATION AND = u LU ♦BLOW COUNT IL- ZJ DEPTH `—' MATERIAL DESCRIPTION Q w a •MOISTURE CONTENT% COMMENTS FEET Q w 0 w < (Tm RQD% 1771 CORE REC% 25 I— 0 50 100 0.0 251.0 Soft to medium stiff, brown SILT(ML), trace sand; moist to wet, sand is fine DCP test at 0.5 foot. (2.25-inch-thick root zone). e�w 2.5— ire _ !I ` s.o— medium stiff, light brown-orange, minor sand; moist at 5.0 feet 11 t 244.5. Exploration completed at a depth of 6.5 6.5 7 5— feet. SPT completed using two wraps with a cathead. 10.0— rw 12.5— err _ 15.0— �rra 17.5— t- Y • O - w 20.0— f- '� I- z CC d 22.5— /Y16 u z Yrr u 25.0— few N z 27.5— to H 5 w V a 30.0 0 50 100 DRILLED BY:Dan J.Fischer Excavating,Inc LOGGED BY:J.Heidgerken COMPLETED:12/18/20 z BORING METHOD:solid-stern auger(see document text) BORING BIT DIAMETER:4 inches 410111 ° G EO DESIGN RELATEDNW-2-01 BORING B-5 ° VAN N VV COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A-5 TIGARD,OR ° O= u L.LJ ♦BLOW COUNT INSTALLATION AND 1-7 DEPTH u MATERIAL DESCRIPTION Q w I,_— °- •MOISTURE CONTENT% COMMENTS FEET w 0 w Q MT1 RQD% 177]CORE REC% ce U Lu ~ 0 50 100 —0.0 237.0 Stiff, light brown-gray with red mottled SILT(ML), minor sand and organics DCP test at 0.5 foot. (rootlets); moist, silt is non-plastic to 44 low plasticity (12-inch-thick tilled zone, 2.5— 4-inch-thick root zone). PP A 1� PP=2.0 tsf Aim PP 14 Infiltration test at 4.0 feet. 5.0— P200 A:� P200=85% PP=2.25 tsf 231.5 yW Exploration completed at a depth of 5.5 5'5 feet. 7.5— SPT completed using two wraps with a cathead. 10.04614 — 12.5- 15.0— trw 17.5— F Y O _ w 20.0— H l7 r z a f- 22.5— ilr+ z - 25.0— m 0 z 27.5— o F- u - a 30.0 0 50 100 a DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:L.Gose COMPLETED:12/02/20 > z p BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:6 inches N DESIGNz RELATEDNW-2-01 BORING B-6 JIU � P DECEMBER 2020 TERRACE GLENN APARTMENTS �I TIGARD,OR FIGURE A 6 ti.. Pi= u w ♦BLOW COUNT INSTALLATION AND DEPTH u Q a Z a •MOISTURE CONTENT% COMMENTS FEET D- a MATERIAL DESCRIPTION >w w a w < FTTT1 RQD% V.71 CORE REC% w H U 246.0 0 50 100 0'° Very stiff, light brown-gray SILT (ML), minor sand; moist, silt is non-plastic to DCPtest at 0.5 foot. low plasticity (8-inch-thick tilled zone, 4- inch-thick root zone). 2.5— 22 PP=2.75 tsf PP •` 5.0— 21 PP=2.25 tsf PP ` 239.5 Exploration completed at a depth of 6.5 6.5 7 5— feet. . SPT completed using two wraps with a cathead. 1o.o— 12.5— 15.0— 17.5— N _ al 20.0 `/lAV H z 22.5- Nitlit > z — 'O*'" u 2 5.0— Z 27.5-- i Q �y� ✓AR W 30.0 cc0 50 100 .,ice, DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:L.Gose COMPLETED:12/02/20 z BORING METHOD:solid-stem auger/see document text) BORING BIT DIAMETER:4 inches MOP DES EOIGNz RELATEDNW-2-01 BORING B-7 �,,,/ J AN N V 5 COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS TIGARD, OR FIGURE A 7 ramsZ 0 °= U w ♦BLOW COUNT INSTALLATION AND DEPTH Q a Z °- •MOISTURE CONTENT% COMMENTS FEET a MATERIAL DESCRIPTION )w N g w < 1711 RQD% 1771 CORE REC% LU 401 " 236.0 0 50 100 -0.0 Very stiff, light brown with gray mottled SILT(ML), minor sand; moist, silt is non- DCP test at 0.5 foot. plastic to low plasticity (6-inch-thick tilled zone, 2-inch-thick root zone). 2.5— 28 PP=1.25 tsf PP 11 •` oho 5.0— light brown with orange mottles at 5.0 feet 19 PP=3.0 tsf YYM PP ` 7.5— �`� medium stiff; wet at 8.0 feet 6 pp PP=1.0 tsf ` 226.5 10.0— Exploration completed at a depth of 9.5 9.5 feet. SPT completed using two wraps with a cathead. *ft 12.5— arer 15.0— UM 17.5— F O _ N - w 20.0 F Z d ▪ 22.5— am U Z U - two , 25.0— m - N z 27.5— H iiWY U - a 30.0 0 50 100 a 7 DRILLED BY:Dan J Fischer Excavating,Inc. LOGGED BY L.Gose COMPLETED:12/02/20 z BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:6 1/4 inches ismo DESIGNz RELATEDNW-2-01 BORING B-8 LJ 'V AN N V 5COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS TIGARD,OR FIGURE A-8 Z "" o _O i u w ♦ BLOW COUNT f'1— Z ii • MOISTURE DEPTHFEET a MATERIAL DESCRIPTION >w N 2 CONTENT% COMMENTS -D w < aiw U w I— VI B-9 250.0 0 50 100 o.o II ASPHALT CONCRETE (11.0 inches). IAN 249.1 Aggregate base well keyed based Exploration terminated at a depth of 0.9 on foundation probe. 0.9 foot due to potential utility conflict. MO CORE DETAILS: No patch observed. 2.5— No crack at core. iiiii eWe 5.0— MI 7.5— war — B10 0 50 100 256.0 0 50 100 s 0.0 ASPHALT CONCRETE (11.0 inches). 255.1 -co AGGREGATE BASE (7.0 inches). 0.9 y.tio 254.5 ,,,, o Medium stiff to stiff, light brown SILT 1.5 N - (ML), minor sand; moist, sand is fine. 2.5— A8 • w simo p z stiff at 3.5 feet a ,ib14 )— MN 0 5.0 251.0 > Exploration completed at a depth of 5.0 5.° CORE DETAILS: z - feet. No patch observed. o No crack at core. u - (Wr o. SPT completed using two wraps with a • cathead. .. 0 y�� 7.5— # Ny o W Q J W K Miii W u a ce W 0 50 100 0 /IYi DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:J.Heidgerken COMPLETED:12/18/20 > z E BORING METHOD:core drill/solid-stem auger(see document text) BORING BIT DIAMETER:5 inches/4 inches U OM o GEO.DESIGN= RELATEDNW-2-01 BORING 2 AN N V 5 COMPANY AN DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A-9 TIGARD,OR A. ca. 2 u w • BLOW COUNT DEPTH Q a z -1 • MOISTURE FEET a MATERIAL DESCRIPTION w o w Q CONTENT% COMMENTS err u w VI B-1 1 257.0 0 50 100 0.0 ASPHALT CONCRETE (11.5 inches). 2 5 6.0 ,OA5 AGGREGATE BASE (3.5 inches). ,21.0 5 5.7 Medium stiff, light brown SILT(ML), 1.3 Wit - trace sand; moist, sand is fine. 11 ` • 2.5— stiff at 3.5 feet 9 5.0 252.0 Exploration completed at a depth of 5.0 5.0 CORE DETAILS: feet. No patch observed. No crack at core. imp SPT completed using two wraps with a cathead. 7.5 0 50 100 4YW 40, I- Y z a H 11Y4 ❑ u z U U O zz ❑ w g u a W C DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:J.Heidgerken COMPLETED:12/18/20 z BORING METHOD:core drill/solid-stem auger(see document text) BORING BIT DIAMETER:5 inches/4 inches U o u RELATEDNW 2 01 BORING �tJES�VNz (continued) NV 5 DOIV1PANY DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A-1 O TIGARD,OR 60 50 CH or OH "A" LINE x 40 >- Z • U 30 I CL or di_ 20 10 MH or OH CL-ML ML ipr OL 0 0 10 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT N ++■• EXPLORATION SAMPLE DEPTH MOISTURE CONTENT LIQUID LIMIT PLASTIC LIMIT PLASTICITY INDEX KEY NUMBER (FEET) (PERCENT) • B-3 15.0 27 49 17 32 LP. 0 MINI f�llll m 3 fYYY a T EODESIGNZ RELATEDNW-2-01 ATTERBERG LIMITS TEST RESULTS AN Nu COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A-1 1 TIGARD,OR yrr 4.0 0• • mob vos 2 _- 3 ark j 4 Z tem w U w a 5 Z Q CC 416 I— in 6 7 diart wW 9 10 � a 100 1 ,000 10,000 100,000 STRESS (PSF) z KEY EXPLORATION SAMPLE DEPTH MOISTURE CONTENT DRY DENSITY ter, u NUMBER (FEET) (PERCENT) (PCF) • B-3 13.0 28 95 zz fYY w cc z CCESIGNz RELATEDNW-2-01 CONSOLIDATION TEST RESULTS z av N V 5 COMPANY DECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A 12 0 TIGARD,OR 41YIY SAMPLE INFORMATION SIEVE ATTERBERG LIMITS MOISTURE DRY adi` EXPLORATION SAMPLE ELEVATION CONTENT DENSITY GRAVEL SAND P200 LIQUID PLASTIC PLASTICITY NUMBER DEPTH (FEET) (PERCENT) (PCF) (PERCENT) (PERCENT) (PERCENT) LIMIT LIMIT INDEX (FEET) B-1 5.0 247.0 26 84 eart B-1 15.0 237.0 25 B-2 5.0 249.0 29 84 B-3 2.5 243.5 28 B-3 13.0 233.0 28 95 B-3 15.0 231.0 27 49 17 32 B-4 5.0 231.0 26 86 B-4 15.0 221.0 33 B-6 2.5 234.5 20 B-6 4.0 233.0 24 85 tiYY B-7 2.5 243.5 15 B-8 2.5 233.5 22 B-8 8.0 228.0 31 B-10 2.0 254.0 22 B-11 1.5 255.5 24 Aim IAA N N (W1i p F.. 4ilY 0 z u A+ • u m 0 zz 0 z iota a CNDESIGNY RELATEDNW-2-01 SUMMARY OF LABORATORY DATA nN N 5 COMPANYDECEMBER 2020 TERRACE GLENN APARTMENTS FIGURE A 1 3 TIGARD,OR 0_ MINI Oil ill IMO EMI d MA» APPENDIX B NEARBY EXPLORATIONS Figures, exploration logs, and laboratory test results from nearby geotechnical explorations are presented in this appendix. 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EVERGREENB-3-01 SITE PLAN I55J5 SW 5epuaia Parkway Suile 100 Portland OB 97224 OCTOBER 2015 PROPOSED SW GREENBURG ROAD DEVELOPMENT FIGURE 2 Off 503 968 8787 fax 503 9683068 TIGARD,OR ,.,, . . * z (ew " = u w ♦BLOW COUNT INSTALLATION AND 0 H DEPTH u Q n- Z ii •MOISTURE CONTENT% COMMENTS FEET a MATERIAL DESCRIPTION w o _I- 2 Q w Q I I I I I ROD% V/a CORE REC% J N sur cc u w I- 0 50 100 0.0 Very stiff, brown with orange mottled _ 1 SILT with sand (ML), trace organics (plant roots); moist, sand is fine to iiii medium (7-inch-thick root zone). 2.5 ill ._— 6 IiIY 5.0— stiff at 5.0 feet n Ali111 A w 7.5— . brown,without organics at 7.5 feet 9 _ 11 ♦ • 10.o—_ medium stiff at 10.0 feet 6 as 12.5— lib 1 s.o— medium stiff to stiff, brown with orange § mottles, minor gravel at 1 5.0 feet lj ♦ • ,irr - - I 17.5— 20.0— m 51.1/s APossible cobbles at 20.0 AI N - Exploration terminated at a depth of 20.3 feet. o — 20.3 feet due to refusal. Surface elevation was not measured at the time of 0 Hammer efficiency factor is unknown. exploration. rri Q 22.5— SPT completed using two wraps with a n — cathead. z - Latitude: 45.45087 - Longitude: -122.77429 -+ks, 0 25.0— (determined from hand-held GPS) u z u 0 1W o u — 27.5— u d 1 'is m 30.0 0 0 50 100 Z ill w DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:10/12/15 cc L.) „w BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:4 1/4 inches w "` g GEODESIGN? EVERGREENB-3-01 BORING B-1 V Z z 15575 SW Sequoia Parkway-Suite 100 PROPOSED SW GREENBURG ROAD DEVELOPMENT m Portland OR97224 OCTOBER2015 FIGURE A-1 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR ie. z O O= L w •♦BLOW COUNT INSTALLATION AND DEPTH u Q 0- Z a •MOISTURE CONTENT% COMMENTS = MATERIAL DESCRIPTION >w I— g FEET a w- w Q 11 I J I RQD% V/CORE REC% Ce MNu w I- 0 50 100 —o.o I Very stiff, light brown with orange mottled SILT with sand (ML), trace organics (plant roots); moist, sand is mg _ fine to medium (7-inch-thick root zone). 2.5—_ [ A 8 i 5.0— stiff, brown at 5.0 feet •1• WO = 7.5 medium stiff to stiff,without organics at 7.5 feet [ A8 Ai lo.o medium stiff at 10.0 feet [ 1 • 12.5— to E 'P o Sift — 'o DI 15.0--- soft to medium stiff; sand is fine to 3 - 4 -o j coarse at 1 5.0 feet A T.; w Ai — — 17.5— 4 — Possible cobbles at 20.0 50/1^ feet. Y zo.o— Exploration terminated at a depth of 20.1 NO • , Sampler was possibly As bouncing off cobbles.at - 20.1 feet due to refusal. 20.0 feet. oPossible water level at 20.0 r, feet. - Hammer efficiency factor is unknown. Srface elevation was w 22.5— SPT completed using two wraps with a measured at the time of t c — cathead. exploration. I- - Latitude: 45.45084 — Longitude: -122.77390 - (determined from hand-held GPS) lila I--0 25.0— u z — u 7, w c — O - V a 27.5— u ui — a IIiIY m 30.0 0 0 50 100 m m flrf w DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:10/12/15 w cc c, BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:4 1/4 inches w ` G EODESIG N? EVERGREENS 3 O1 BORING B-2 u z re 15575 SW Sequoia Parkway-Suite 100 PROPOSED SW GREENBURG ROAD DEVELOPMENT m Portland OR97224 OCTOBER 2015 FIGURE A-2 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR z '" " 0 INSTALLATION AND O = U w A BLOW COUNT DEPTH u Q a Z a •MOISTURE CONTENT% COMMENTS FEET a MATERIAL DESCRIPTION w I- g w Q I I I I I RQD% V/)CORE REC% J to aro u w I- 0 50 100 —0.0 Al-SPHALT CONCRETE(3.0 inches). , 0.3 \AGGREGATE BASE (5.0 inches). 1 0.7 Stiff, brown SILT with sand (ML), trace AO - organics (plant roots); moist, sand is 2.5— fine to medium (7-inch-thick root zone). Ilil .1 Au' `o s.o— medium stiff to stiff at 5.0 feet [ i iiii 7.5 stiff,without organics at 7.5 feet 9 iwr _ 11 ♦ • iiii 10.0— medium stiff at 10.0 feet _ 6 - ail 12.5— 15.0— soft to medium stiff to stiff at 15.0 feet _ 111 4 {iYW 17.5— iiiio 1- 20.0 hard, red-brown with black mottles, 41 air C^ _ minor gravel; sand is fine to coarse • A 20.0feet o 21.5 Surface elevation was not - Exploration terminated at a depth of measured at the time of 22.5— 21.5 feet due to refusal. exploration. 1- airs a 0 Z --IHammer efficiency factor is unknown. - SPT completed using two wraps with a - cathead. two o 25.0— Latitude: 45.45052 u. - Longitude: -122.77396 L - (determined from hand-held GPS) w 0 40, o _ u i, 27.5— u a r- ails u; m 30.0 0 0 50 100 r+i m „z, DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:10/12/15 w 5 u c, BORING METHOD:solid-stern auger(see document text) BORING BIT DIAMETER:4 1/4 inches w uo G EODESIG NZ EVERGREENB 3 01 BORING B-3 z s 15575 SW Sequoia Parkway-Suite 100 m Portland OR97224 OCTOBER 2015 PROPOSED SW GREENBURG ROAD DEVELOPMENT FIGURE A-3 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR ire, im u z O = u w BLOW COUNT INSTALLATION AND DEPTH v Q a Z n •MOISTURE CONTENT% COMMENTS FEET d MATERIAL DESCRIPTION w o g w < I I I I I RQD% I//,I CORE REC% J N ohce u w ~ 0 50 100 0.0 Stiff, brown with light brown and orange mottled SILT with sand (ML), trace organics (plant roots); moist, sand _ is fine to medium (6-inch-thick root 2.5— zone). _ FA0. irk 5.0— medium stiff, brown with light brown = mottles at 5.0 feet [ A _ - 7.5— = brown at 7.5 feet iiiiiill i • illg 10.0- - 5 11 12.5— o+ F. -a - or iiira B 15.0— soft to medium stiff; sand is fine to 4 coarse at 1 5.0 feet A ,22 eau o 2_ 17.5— - • ism - I 20.0 -- - 20.0 Heavy chatter at 19.5 feet. I- Dense, brown with orange and black41 Possible water level at 20.0 Yw mottled SAND with silt and gravel (SP- AIll feet. - SM); moist, fine to medium. 21.5 Surface elevation was not o - Exploration terminated at a depth of measured at the time of twit I- 22.5— 21.5 feet due to refusal. exploration. o - Z Hammer efficiency factor is unknown. - SPT completed using two wraps with a - cathead. elow 0 25.0— Latitude: 45.45066 z - Longitude: -122.77351 N - (determined from hand-held GPS) 0 duo o _u — 27.5— cL a - I- -Wi II), m 0 30.0 0 50 100 m iioo E DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:10/12/15 ti u LLi., BORING METHOD:solid-stern auger(see document text) BORING BIT DIAMETER:4 1/4 inches > u, """ O GEODESIGN? EVERGREENB-3-01 BORING B-4 u z Fe 15575 SW Sequoia Parkway-Suite 100 Portland OR97224 OCTOBER 201 5 PROPOSED SW GREENBURG ROAD DEVELOPMENT FIGURE A-4 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR ■will kilit O Q i u Lu ♦BLOW COUNT INSTALLATION AND DEPTH L.) Q a Z a •MOISTURE CONTENT% COMMENTS FEET a MATERIAL DESCRIPTION w o , g w < I J I RQD% V/I CORE REC% tow u w I— N 0 50 100 —0.0 Stiff, brown with light brown and orange mottled SILT with sand (ML); moist, sand is fine to medium (6-inch- oh thick root zone). 2.5— A1• *l 5.0— brown with light brown mottles at 5.0 9 ow feet [ A 7.5 medium stiff to stiff, brown with black i"" mottles at 7.5 feet [ 2 • 10.0- medium stiff at 10.0 feet — 6 11 iiiii 12.5— 4Wr 15.0— stiff; sand is fine to coarse at 15.0 feet F �2 r —- ^~ 'MNVery dense, gray and brown SAND with 16.3 — silt and gravel (SP-SM); moist, fine to 17.5— '• coarse. 440, - - • 20.0— with black mottles at 19.5 feet P200 11 • 7-22-J0/1"A P200=30% Y Viol '^ Exploration terminated at a depth of 20.6 Surface elevation was not G measured at the time of — 20.6 feet due to refusal. exploration. 0 - 22.5— Hammer efficiency factor is unknown. 1-- wit c, - SPT completed using two wraps with a z - cathead. - Latitude: 45.45039 • - Longitude: -122.77349 `.r o 25.0— (determined from hand-held GPS) u z - u O +rr u s 27.5— u - a H 6 - 30.0 0 0 50 100 ni m (IIW w DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:10/12/15 w C L., w BORING METHOD:solid-stem auger(see document text) BORING BIT DIAMETER:4 1/4 inches 1YY o GEODESIGNz EVERGREENB-3-01 BORING B-5 u z z 15575 SW Sequoia Parkway-Suite 100 Portland OR97224 OCTOBER 2015 PROPOSED SW GREENBURG ROAD DEVELOPMENT FIGURE A-5 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR z rr+ o Q H U w ♦BLOW COUNT INSTALLATION AND DEPTH u Q I- z a •MOISTURE CONTENT% COMMENTS = MATERIAL DESCRIPTION >w 1= g FEET a w� w < I W I I I RQD% V/,)CORE REC% J N + u cc w H 0 50 100 —o.o—T- Stiff, brown with light brown and - orange mottled SILT with sand (ML), trace organics; moist, sand is fine to rim. - medium (6-inch-thick root zone). - 2.5— - I Ar s.o— , medium stiff to stiff, brown,without 10 *go _ organics at 5.0 feet A 7.5 medium stiff at 7.5 feet WM [ 1 kill 10.0— soft to medium stiff at 10.0 feet 4 12.5— a, c -`o - m Yiit `- 15.0— -o - - 4 w [ A o 1iiii - 17.5— iiiii Possible water level at 18.0 - medium stiff to stiff, gray at 18.5 feet feet. 11 zo.o— very dense, brown and orange with Y black mottles at 19.5 feet 32 i""' C _ Dense, brown and gray SAND with silt 20.5 2 „ .. and gravel (SP-SM); moist, fine to - coarse. III 22.5— . -.. Q I- 2 very dense at 23.0 feet F 50/6"A z 23.5 Surface elevation was not a - Exploration terminated at a depth of measured at the time of a - 23.5 feet due to refusal. exploration. im* 0 25.0— u. - Hammer efficiency factor is unknown. u SPT completed using two wraps with a o - cathead. N,, ° - Latitude: 45.45030 • 27.5— Longitude: -122.77297 - (determined from hand-held GPS) 1- _ 410 m 30.0 0 0 50 100 „z, DRILLED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:10/12/15 iiiiiw z u w BORING METHOD:solid-stern auger(see document text) BORING BIT DIAMETER:4 1/4 inches """ GEODESIGNZ EVERGREENB-3-01 BORING B-6 u z c 15575 SW Sequoia Parkway-Suite 100 m Portland OR97224 OCTOBER 2015 PROPOSED SW GREENBURG ROAD DEVELOPMENT FIGURE A-6 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR Z IMO U O o, U w Z a ••MOISTURE COMMENTS DEPTH = MATERIAL DESCRIPTION >I-i-I I— g CONTENT FEET a w Q (%) ce w I— v) um U TP-1 0.0 0 50 100 Medium stiff to stiffilie , brown SILT with sand (ML), trace organics; moist, sand is El fine to medium (18-inch-thick tilled \zone, 8-inch-thick root zone). J 1.5 2.5— Stiff to very stiff, brown SILT with sand PP ® PP=>4.5 tsfiii - (ML); moist, sand is fine to medium. _- brown with light brown and orange 5.o— mottles at 4.0 feet tor - brown with light brown mottles at 6.5 aim 7.5— feet - brown at 9.0 feet Ala 10.0 - Exploration completed at a depth of 10.0 ® No groundwater seepage observed - 10.0 feet. at the time of exploration. No caving observed at the time of 4w - Latitude: 45.45081 exploration. 12.5— Longitude: -122.77436 Surface elevation was not (determined from hand-held GPS) measured o at the time of exploration. imi TP 2 0 50 100 0 50 100 A 0.0 1 Medium stiff to stiff, brown SILT with _ sand (ML), trace organics and debris (brick rubble, glass, and metal); moist IX 1- —--i (18-inch-thick tilled zone, 7-inch-thick 2.0 •• 2.5— \root zone) - FILL. — Stiff to very stiff, brown SILT with sand - (ML), trace organics; moist. PP ® PP=>4.5 tsf w - brown with light brown and iimi 0 5.0— mottles at 4.0 feet I— — Z a Vasa o - brown at 7.0 feet c, 7.5— z — u o Z 0 ar u F. 10.0 - Exploration completed at a depth of 10.0 No groundwater seepage observed i6 1 0.0 feet. at the time of exploration. F _ No caving observed at the time of a'"' `°i — Latitude: 45.45067 exploration. 12.5— Longitude: -122.77436 - (determined from hand-held GPS) Surface elevation was not measured at the time of Z exploration. wr w V th j 0 50 100 w w Aia EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:09/24/15 a z w o. EXCAVATION METHOD:backhoe(see document text) N ° EVERGREENB-3-01 woo TEST PIT ▪ G EOUESIGNu _ v~i 15575 SW Sequoia Parkway-Suite 10o PROPOSED SW GREENBURG ROAD DEVELOPMENT Portland OR 97224 OCTOBER 2015 FIGURE A-7 • Off 503.968.8787 Fax 503.968.3068 TIGARD,OR z AN U O I Z a ••MOISTURE DEPTH = MATERIAL DESCRIPTION >1-0 ►- g CONTENT COMMENTS FEET < w LI-IQ (%) OW V VI TP-3 0.0 0 50 100 - Medium stiff to stiff, brown SILT with ""` _ sand (ML), trace organics and debris El (shingle); moist (18-inch-thick tilled - -1\zone, 7-inch-thick root zone)- FILL. / t.5 2.5— Stiff to very stiff, brown with light pp M pp=>4.5 tsf `lio — brown and orange mottled SILT with - sand (ML), trace organics; moist. light brown and brown at 4.0 feet 440 5.0— brown with light brown mottles,without ,,,, 7.5— organics at 6.5 feet - brown at 8.5 feet ilia i o.o Exploration completed at a depth of - 10•0 ® No groundwater seepage observed 10.0 feet. at the time of exploration. No caving observed at the time of ileg - Latitude: 45.45052 exploration. 12.5— Longitude: -122.77349 Surface elevation was not (determined from hand-held GPS) measured o at the time of exploration. sire TP-4 0 50 100 0 50 100 0.0 Medium stiff to stiff, brown SILT with _ sand (ML), trace organics; moist (16- to - 18-inch-thick tilled zone, 6-inch-thick Z - 1 root zone). Trace ashes at 1.9 feet sa ,,, 2.5— stiff to very stiff, brown with light brown and orange mottles at 2.0 feet o _ I pp ® • PP=4.5 tsf Li F taw < 5.0— o _ brown with light brown mottles at 5.0 z feet Tree roots (3/4-inch diameter) at Z 6.0 feet V 7.5— I z - V o _- I iota 0 u 7 o.o u Exploration completed at a depth of 700 No groundwater seepage observed - 10.0 feet. at the time of exploration. No caving observed at the time of - Latitude: 45.45038 exploration. 12.5— Longitude: -122.77330 (determined from hand-held GPS) Surface elevation was not o measured at the time of z - exploration. rill w a V a > 0 50 100 w w Mil a EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:09/24/15 a a w a EXCAVATION METHOD:backhoe(see document text) N ° u EVERGREENB-3-01 TEST PIT GEODESIGNZ w 15575 SW Sequoia Parkway-Suite I00 PROPOSED SW GREENBURG ROAD DEVELOPMENT Portland OR 97224 OCTOBER 2015 FIGURE A-8 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR iYr z IAN u 9 -I u W •MOISTURE DEPTH u Q 0- z a COMMENTS FEET d MATERIAL DESCRIPTION w o g CONTENT J w Q (Is) ce ce w I— rn u TP-5 0.0 0 50 100 - Medium stiff to stiff, brown SILT with iito _ sand (ML), trace organics; moist (14- - inch-thick tilled zone, 5-inch-thick root Trace ashes at 1.5 feet - zone). Tree roots (3/4-to 1-inch 2.5— stiff to very stiff, brown with light diameter)to 2.0 feet ter - brown and orange mottles at 1.3 feet PP ® 40 PP=>4.5 tsf brown with gray mottles at 3.5 feet 5.0-- - 1 7.5— brown at 7.0 feet iiii 10.0 No groundwater seepage observed Exploration completed at a depth of lo.o ® at the time of exploration. 10.0 feet. No caving observed at the time of exploration. r Latitude: 45.45054 12.5— Longitude: -122.77310 measuredrface elevation was t at the time of (determined from hand-held GPS) exploration. TP-6 o So loo 0 50 100 u.. 0.0 Medium stiff to stiff, brown SILT with sand (ML), trace organics; moist (18- inch-thick tilled zone, 6-inch-thick root ® 0 zone). Trace ashes at 1.7 feet iris - 2.5— stiff to very stiff, brown with light - brown and orange mottles at 1.5 feet o PP ® PP=>4.5 tsf - w - i- Ww o 5.0 o— brown with gray mottles at 5.0 feet i- - Z iiiii I- u 7.5— N _ without organics at 8.0 feet o _ r,,; 8 - brown at 9.0 feet 10.0 Exploration completed at a depth of 10.0 No groundwater seepage observed `° 10.0 feet. at the time of exploration. - No caving observed at the time of iD, - Latitude: 45.45035 exploration. 12.5— Longitude: -122.77288 (determined from hand-held GPS) ae elevation was not - measured at the time of z exploration. Orr w - w u z j 0 50 100 w a EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:TJS COMPLETED:09/24/15 a cc w a EXCAVATION METHOD:backhoe(see document text) N `""' 1 GEODESIGNz EVERGREENB-3-01 TEST PIT v~i i 5575 SW Sequoia Parkway-Suite t oo PROPOSED SW GREENBURG ROAD DEVELOPMENT Portland OR97224 OCTOBER 2015 FIGURE A-9 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR tirr rr SAMPLE INFORMATION SIEVE MOISTURE DRY ATTERBERG LIMITS SAMPLE CONTENT DENSITY ELEVATION EXPLORATION DEPTH GRAVEL SAND P200 LIQUID PLASTIC PLASTICITY NUMBER (FEET) (FEET) (PERCENT) (PCF) (PERCENT) (PERCENT) (PERCENT) LIMIT LIMIT INDEX B-1 2.5 12 B-1 7.5 26 wri B-1 15.0 30 B-2 5.0 20 wit B-2 10.0 27 B-2 20.0 29 art B-3 2.5 16 B-3 7.5 27 ffW B-3 20.0 27 B-4 2.5 18 tier B-4 7.5 27 B-5 2.5 19 I- B-5 7.5 27 dr B-5 19.5 33 30 B-6 2.5 17 tr,r TP-1 0.5 11 TP-3 0.5 12 urr TP-4 3.5 20 0 o TP-5 2.5 13 W ww a TP-6 1.0 9 ce d vita U Lcti YfY O 44. 0 om Elm ENO U G EO DES I G NZ EVERGREENB-3-01 SUMMARY OF LABORATORY DATA M 15575 SW Sequoia Parkway-Suite 100 Portland OR OCTOBER 2015 PROPOSED SW GREENBURG ROAD DEVELOPMENT J Off 503.968.8787 Paxx 503 503.968.3068 TIGARD, OR FIGURE A-10 .6Y+ r .. He Name `t en J:\E-L\evergreen6\evergree 6 3\eyergr ee b 3 Of\Figures\CAD\E gree g 3-01-$Pol-pavementdwg I Layout:FIGURE 2 Y +,.. t!-... 1MR 3 ., . • .. . . .. , . g.,,. . 1 . . . ., 1., ...,.„, •, I. . . . .„. , SJg,-G,? 1,„.. - , ..... ... ... „„ .....:„.„„ -, ,,, 6 4 I I I- B " • 6� d} Ptyf rx "° 3/' 4 r. °" r n" �, ems`# 3 r-'/ .'!}ft)/. :i4C•-•---4,,:1i4l,.-L-!4ii,ftilgt0;t0g4*qr•tu.:%i:-1•V,: tf#ifs ° ya f a + .r_ r m„ 0 W m ,,,,!,,,.....,:: 1.:'," Z D O ' OZ orn � n o°n Z D (*; n 0 n a ll:; r� Z O Z m T ill D f- ,, D -I v �-i < =2 m O - a O 0n Z ®z n 0.v o 0 I z m cor. 0 7. r5,�: Z i/*.f,/ GEODESIGN= 1;F, EVERGREENS-3-Ol sns swsa9�oa Panwav-s�m i 66 /I Portland ORm. .I,f: Off 503.968.81eJ Fix 503 9fi6.3069 Ff DECEMBER 2015 PROPOSED SW GREENBURG ROAD DEVELOPMENT Mill f �. TIGARD,OR j lJ z O= u w A BLOW COUNT DEPTH u Q a z 62 • MOISTURE FEET a MATERIAL DESCRIPTION >o g CONTENT% COMMENTS Q LU CC w I-- ti C-1 III0.0 ASPHALT CONCRETE (13.5 inches). 0 50 100 Stiff, brown SILT(ML), minor clay; moist. 1 11 2.5— - 14 Exploration completed at a depth of 4.0 4.0 - feet. 5.0— CORE DETAILS: Hammer efficiency factor is unknown. No patch observed. No crack on core. SPT completed using two wraps with a cathead. Latitude: 45.450846 Longitude: -122.774554 (determined from GPS) 7.5— -2 0 50 100 o.0 0 so 100 ASPHALT CONCRETE (1 3.5 inches). - Very stiff, red brown SILT(ML), minor 1.1 r sand, trace clay; moist, sand is fine. r6 _ U z 2.5 L — N. w N stiff at 3.0 feet 2• Q 0 H z Exploration completed at a depth of 4.5 4'5 5•0— feet. H CORE DETAILS: 0 Hammer efficiency factor is unknown. No patch observed. No crack on core. z SPT completed using two wraps with a o cathead. o _ Latitude: 45.451002 Longitude: -122.774516 E- 7.5— (determined from GPS) u N U a; I m I L, w w z v ce w 0 50 100 w mom d DRILLED BY.Dan J.Fischer Excavating,Inc. LOGGED BY.JCH COMPLETED:12/11/15 w a BORING METHOD.core drill/solid-stem auger(see document text ) BORING BIT DIAMETER:5 inches/4 inches o GEODESIGNz EVERGREENB-3-01 BORING E2 15575 SW Sequoia Parkway-Suite 100 m Portland OR97224 DECEMBER 2015 PROPOSED SW GREENBURG ROAD DEVELOPMENT ' Off 503.968.8787 Fax 503.968.3068 TIGARD, OR FIGURE A--1 1 1 Y 1 1 1 1 1 1 1 1 1 1 1 APPENDIX C INFILTRATION TEST DATA Plots of the infiltration test data we collected from borings B-1 , B-2, B-4, and B-6 are presented in this appendix. We performed the infiltration tests inside pipes that we inserted into the boreholes. We performed the testing using the encased falling head test method. We performed the testing with a water head of approximately 3 to 4 feet. We collected water level readings using an electronic water level indicator data logger. ram,: I I I I I I I I p trip! DESIGNz "'` V C-i RelatedNW-2-01:123120 um CO 01 N Jew CU 0 1 Liiii On Cr) 4-, V) G) 411. ii if N I ..,...._. , Cl.) LL. 0 lit .7r ..n 0 1 en ....11\ . 0 his -I-P 0 i a) (1) G) 4-+ 4— #iiill (73 "4111lair",:- itips„, --""1111111111•Zolirr-• -C3 CO a) 1 rri kw 411 4.4400._ C.) 5-. = -.1.0......„ = CU 0 "*.711111111141111111111441.001...... s_ 0 12_ tista CO ,—I rri r-- ....„ C N 0 ,—! s- 4-; --.41.4401._ .....7•:..,..... , L = ct 1 • — ro fr I 1.: 16 1141 Lo I cri I 00 1-i r o 1.11 0 L,P, o L 0 L.r) o CNI ,-I r-4 f) ,--i r-i N (mai _tad saipu!) alrej uo!lani!jui 6 00 0 C Lie . . lir 4-, CD LA a) L.;,: ii 'i c:u CD LL cri 0 II i.li, . Ln 4- 0 II -C 4-, CD- , M CD I 0 -I-3 (73 (1) a) 4- -C$ Ni ro LD a) I CCI t1C -I . 1 cy) a) I- C tr) v) I .L.- 0 CC) c12 in.. 00 . . 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