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Report OFFOCE COP ST201_ 0 - GIs CATAAO.rv, 1512-1 MsW-, j IRO 1c 9750 SW Nimbus Avenue RECEIVE D Beaverton, 97008 7172 x oaD p 503 641-3 347$ f 503 644 8034 MAY 3 U 2019 Terrace. CITY OF TIGARD BUILDING DIVISION April 19, 2019 5970-K GEOTECHNICAL RPT Tigard-Tualatin School District Of°Ce Co 6960 SW Sandburg Street Tigard, OR 97223 Attention: Debbie Pearson/DAY CPM SUBJECT: Geotechnical Investigation and Site-Specific Seismic-Hazard Evaluation Art Rutkin Elementary School 15727 SW Taylor Lane Portland, OR As requested, GRI completed a geotechnical investigation for the proposed new Art Rutkin Elementary School located at 15727 SW Taylor Lane in Portland, Oregon. The Vicinity Map,Figure 1,shows the general location of the site. The purpose of the investigation was to evaluate subsurface conditions at the site and develop geotechnical recommendations for use in the design and construction of the proposed new school. The investigation included a review of existing geotechnical information for the site and surrounding area, subsurface explorations, laboratory testing, and engineering analyses. As part of our investigation, GRI completed a site-specific seismic-hazard evaluation to satisfy the requirements of the 2012 International Building Code (IBC),which was adopted by the 2014 Oregon Structural Specialty Code (OSSC). This report describes the work accomplished and provides conclusions and recommendations for use in the design and construction of the proposed project. BACKGROUND INFORMATION We reviewed the following report provided by you for the property: "Preliminary Report of Geotechnical Engineering Services, Thorpe Property, 15727 SW Taylor Lane, Tigard, Oregon," dated July 12, 2006, by GeoDesign, Inc. SITE DESCRIPTION General The proposed Art Rutkin Elementary School campus encompasses about 20 acres of undeveloped land that is generally bordered by SW Finis Lane on the east and undeveloped property with single-family homes on the north, south, and west. We understand the northern portion of the property was heavily forested prior to logging a few years ago. The proposed school campus will be located in the western portion of the property with the school entrance and parking lots located along the western property margin. Our observations on site and review of topographic information provided by KPFF, Inc.,the project civil engineer, indicate the ground surface slopes downward from north to south across the campus, with about 60 to 70 ft of elevation difference across the site. GEOTECHNICAL• PAVEMENT■GEOLOGICAL■ ENVIRONMENTAL Since 1984 Geology Published geologic mapping indicates the site is mantled with residual soils produced from the weathering of the underlying Columbia River Basalt (Madin, 2004). These residual soils typically consist of brown to red-brown silt and clay soils of relatively high plasticity that exhibit relict structures of the weathered rock. The weathering profile of the basalt grades from residual soil to hard rock with increasing depth within a given flow. PROJECT DESCRIPTION We understand the new Art Rutkin Elementary School will be constructed under the 2016 Tualatin-Tigard School District Bond Program. Our project understanding is based on review of Schematic Design Plans provided by KPFF, Inc., the project civil engineer, titled "Art Rutkin Elementary School, Tigard Tualatin School District," dated March 26, 2019. The plans indicate the new school building and associated improvements will occupy the western portion of the 20-acre site. The Site Plan, Figure 2,shows the planned location of the new school and associated improvements. Review of the schematic design plans indicates the new school will consist of a one-to two-story at-grade structure benched into the existing hillside. We understand portions of the structure will have partially embedded walls and the maximum height of cuts and fills to establish the finished floor elevation will be on the order of 10 and 15 ft, respectively. Structural information provided by Catena Consulting Engineers, Inc.,the project structural engineer, indicates the new school building will have maximum wall and column loads on the order of 3 kips/ft and 90 kips,respectively. We anticipate the new school building will be designed in accordance with the 2012 IBC, which was adopted by the 2014 OSSC. Entrance to the campus and parking will be provided at the western margin of the proposed school building and will be accessible from the west. We anticipate the height of cuts and fills required to establish finished grades for the drive lanes, parking lots, and other ancillary improvements will be on the order of 5 to 20 ft. Retaining structures, such as cantilever, mechanically stabilized earth (MSE), or soil nail walls, will likely be required to maintain the finished site grades. We anticipate the entrance driveways and parking lots will be paved with asphalt concrete (AC) and areas subjected to heavy traffic loads, such as trash enclosure areas, will be paved with portland cement concrete (PCC). A soft-and hard-surfaced play area will be constructed immediately south of the school within the southwest portion of the site. We understand a stormwater facility is proposed along the southern property boundary. SUBSURFACE CONDITIONS General Subsurface materials and conditions at the site were investigated on December 13 and 14, 2018, and April 3 and 4, 2019, with 13 borings, designated B-1 through B-13, six test pits, designated TP-13 through TP-18, and six Kessler Dynamic Cone Penetration (DCP) probes, designated DCP-1 through DCP-6. Six of the borings were advanced to depths of about 6.5 ft below existing site grades in the proposed pavement areas, five of the borings were advanced to depths of about 10.9 to 22.5 ft below existing site grades in the proposed building footprint, and two of the borings were advanced to depths of about 29 to 32 ft below existing site grades in the vicinity of the proposed retaining wall located near the north site boundary. The test pits were excavated to depths of about 11.5 to 18.5 ft below existing site grades in the vicinity of the proposed retaining walls located near the north and south site boundaries. The DCP probes were completed in the pavement borings to a depth of about 4 ft below existing site grades. The approximate locations of the explorations G ®a2 completed for this investigation are shown on Figure 2. Logs of the borings and test pits are provided on Figures 1 A through 19A. The field and laboratory programs conducted to evaluate the physical engineering properties of the materials encountered in the explorations are described in Appendix A. The terms and symbols used to describe the materials encountered in the explorations are defined in Tables 1 A through 2A and the attached legend. Subsurface information from 12 test pit excavations, designated TP-1 through TP-12, completed by GeoDesign, Inc., were included in our review of existing data for this project. The test pits were excavated to depths of about 4 to 12.5 ft below existing site grades at the approximate locations shown on Figure 2. Logs of the test pit excavations are provided in Appendix B for reference. Sampling Disturbed and undisturbed soil samples were obtained from the borings at 2.5-ft intervals of depth in the upper 15 ft and 5-ft intervals below 15 ft. Disturbed soil samples were obtained using a 2-in.-outside- diameter (O.D.) standard split-spoon sampler. Standard Penetration Tests (SPT) were conducted by driving the samplers into the soil a distance of 18 in. using a 140-lb hammer dropped 30 in. The number of blows required to drive the sampler the last 12 in. is known as the Standard Penetration Resistance,or SPT N-value. SPT N-values provide a measure of the relative density of granular soils and the relative consistency of cohesive soils. Relatively undisturbed soil samples were collected by pushing a 3-in.-O.D. Shelby tube into the undisturbed soil a maximum of 24 in. using the hydraulic ram of the drill rig. The soil in the Shelby tubes was extruded in our laboratory and Torvane shear strength measurements were recorded on selected samples. In addition, core samples of basalt were obtained using HQ rock coring techniques. Soils For the purpose of discussion, the materials disclosed by our investigation have been grouped into the following categories based on their physical characteristics and engineering properties: 1. Silty CLAY to Clayey SILT(Residual Soil) 2. Silty SAND (Decomposed Basalt) 3. BASALT(Columbia River Basalt) The following paragraphs provide a description of the materials encountered in the explorations completed by GRI for this investigation and a discussion of the groundwater conditions at the site. 1. Silty CLAY to Clayey SILT (Residual Soil). Residual soil consisting of silty clay to clayey silt was encountered at the ground surface in all the explorations. The residual soil is derived from the weathering of the underlying Columbia River Basalt and extends to depths of about 6.5 to 15 ft. In general, the soil is brown with varying degrees of gray mottling and contains up to a trace of fine-grained sand and organics. Gravel-to boulder-size fragments of decomposed basalt were encountered throughout the unit in exploration TP-15. The relative consistency of the soil is medium stiff to very stiff based on SPT N-values of 4 to 21 blows/ft and Torvane shear-strength values of 0.25 to 0.60 tsf; however, an SPT N-value of 2 blows/ft disclosed a 2.5-ft-thick zone of very soft to soft soil at the ground surface in explorations B-7 and B-11. The natural moisture content of the soil ranges from 18 to 40%. Atterberg limits test results indicate the soil has a liquid limit of 46 to 52% and plasticity index of 18 to 29%, see Figure 20A. G ®0 3 One- dimensional consolidation testing was completed on samples of residual soil obtained at depths of about 3.0 and 4.2 ft in explorations B-4 and B-10, respectively. Test results indicate the residual soils is overconsolidated and exhibits a relatively low compressibility in the preconsolidated range of pressures and moderate compressibility in the normally consolidated range of pressures, see Figures 21A and 22A. Explorations B-1, B-2, B-5, B-7, B-8, and B-11 were terminated in residual soil at a depth of about 6.5 ft. 2. Silty SAND(Decomposed Basalt). Decomposed basalt in the form of silty sand was encountered beneath residual soil in explorations B-3, B-4, B-6, B-12, B-13, and TP-14 through TP-17. The thickness of the decomposed basalt unit is variable, ranging from 1.5 to 7.5 ft thick, and extends to depths of about 10 to 17 ft. In general, the soil is green-gray to gray with rust staining and contains fine-to coarse-grained sand and gravel-sized fragments of predominantly decomposed basalt. Green, white, pink, and red mineralization and relict rock structures are present throughout the unit. Our drilling for the project and our experience in the site vicinity indicate this deposit usually contains gravel- to boulder-sized fragments of predominantly decomposed basalt. The relative density of the silty sand is medium dense to very dense based on SPT N- values of 15 to 74 blows/ft and is typically dense. The natural moisture content of the silty sand ranges from 26 to 44%. 3. BASALT (Columbia River Basalt). Extremely soft (RO) to hard (R4) basalt of the Columbia River Basalt Group was encountered beneath silty clay to clayey silt (residual soil) in explorations B-9, B-10, TP-13, and TP-18 and beneath silty sand (decomposed basalt) in explorations B-3, B-4, B-6, B-12, B-13, and TP-14 through TP-17. The basalt was encountered at depths of about 7.5 to 17 ft and extends to the maximum depth explored of about 32 ft. In explorations B-6, B-12, and B-13, the basalt was cored below a depth of about 12.5 to 28 ft. The quality of basalt,as measured by the degree of hardness and weathering, was highly variable. Core recovery ranged from 30 to 70%. The basalt has some vesicles and open joints with clay infilling, resulting in typical rock quality designations (RQD) of 0 to 10%. The joints and fractures displayed some staining, and secondary mineralization was observed on some joint and fracture faces and in some vesicles. Typically, the basalt is gray and black or brown and predominantly decomposed to decomposed near the top of the unit and grades to slightly weathered with depth. Explorations B-3, BA, B-6, B-9, B-10, B-12, B-13, and TP-13 through TP-18 were terminated in basalt at depths of about 11 to 32 ft. Groundwater Groundwater seepage was not encountered at the time of drilling in six of the borings completed using hollow-stem auger drilling techniques and was not encountered at the time of excavation of the test pits. The remaining seven borings were completed using mud-rotary drilling techniques, which do not allow an accurate measurement of the groundwater level during drilling. Our review of U.S. Geological Survey (USGS) groundwater data suggests the regional groundwater level at the site typically occurs at depth in the highly fractured, hard basalt that underlies the site (Snyder, 2008). However, our experience in the project vicinity indicates perched groundwater can occur in the residual soil and decomposed basalt that mantle the site, particularly following periods of intense or prolonged precipitation. GRII 4 Infiltration Testing On December 14, 2018, falling head infiltration tests were conducted in two boreholes designated I-1 and 1-2 at a depth of about 3 ft below existing site grades. The approximate locations of the infiltration tests are shown on Figure 2, within the proposed stormwater facility footprint. The unfactored, field-measured infiltration rates recorded at a specific depth within a specific soil unit are tabulated below. Details regarding the infiltration testing methods are provided in Appendix A. INFILTRATION TEST RESULTS Depth of Average Infiltration Boring Infiltration Test,ft Rate, in./hour Soil Classification I 1 3.0 0.0 Clayey Silt to Silty CLAY (Residual Soil) 1-2 3.0 0.0 Clayey Silt to Silty CLAY (Residual Soil) CONCLUSIONS AND RECOMMENDATIONS General Subsurface conditions disclosed by the explorations completed for this investigation are consistent with conditions encountered during previous investigations completed at the site. The explorations indicate the site is mantled with residual soil underlain by decomposed basalt produced by the weathering of the underlying Columbia River Basalt. Groundwater was not encountered at the time of exploration; however, we anticipate perched groundwater may approach the ground surface at the site during the wet winter months or following intense or prolonged precipitation. In our opinion,foundation support for new structural loads can be provided by conventional spread and wall foundations established in firm, undisturbed native soil or compacted structural fill. The primary geotechnical considerations associated with construction of the new school and associated improvements include the presence of fine-grained soils at the ground surface that are extremely sensitive to moisture content; the potential for shallow, perched groundwater conditions; the potential for sheeting surface water off the hillside; and the presence of shallow basalt. The following sections of this report provide our conclusions and recommendations for use in the design and construction of the project. Seismic Considerations General. We understand the project will be designed in accordance with the 2012 IBC with 2014 OSSC modifications. For seismic design, the 2012 IBC references the American Society of Civil Engineers (ASCE) Document 7-10, Minimum Design Loads for Buildings and Other Structures (ASCE 7-10). A site-specific seismic-hazard evaluation was completed for the project in accordance with the 2014 OSSC. Details of the site-specific seismic hazard evaluation and the development of the recommended response spectra are provided in Appendix C. Code Background. The 2012 IBC and ASCE 7-10 seismic hazard levels are based on a Risk-Targeted Maximum Considered Earthquake (MCER) with the intent of including the probability of structural collapse. The ground motions associated with the probabilistic MCER represent a targeted risk level of 1% in 50 years probability of collapse in the direction of maximum horizontal response with 5% damping. In general,these risk-targeted ground motions are developed by applying adjustment factors of directivity and risk coefficients GRU 5 to the 2% probability of exceedance in 50 years, or 2,475-year return period, hazard-level (MCE) ground motions developed from the 2014 USGS Unified Hazard Tool (USGS, 2014). The risk-targeted probabilistic values are also subject to a deterministic limit. The code-based, ground-surface, MCER-level spectrum is typically developed using the mapped bedrock spectral accelerations, Ss and Si, and corresponding site coefficients, Fa and Fv,to account for site soil conditions. Site Response. The ASCE 7-10 methodology uses two bedrock spectral response parameters, Ss and Si, corresponding to periods around 0.2 and 1.0 second to develop the MCER response spectrum. To establish the ground-surface MCER spectrum, these bedrock spectral coefficients are adjusted for site class using the short- and long-period site coefficients, Fa and Fv, in accordance with Section 11.4.3 of ASCE 7-10. The design-level response spectrum is calculated as two-thirds of the ground-surface MCER spectrum. The maximum horizontal-direction spectral response accelerations were obtained from the USGS Seismic Design Maps for the coordinates of 45.4071° N latitude and 122.8454° W longitude. The Ss and Si parameters identified for the site are 0.95 and 0.42 g, respectively, for Site Class B, or bedrock conditions. Based on our review of Section 20.4.2 of ASCE 7-10,the subsurface conditions disclosed by the explorations, and the results of our site-specific seismic hazard evaluation, the soil profile at the site is representative of Site Class C conditions. The recommended MCER- and design-level spectral response parameters for Site Class C conditions are tabulated below and discussed in further detail in Appendix C. RECOMMENDED SEISMIC DESIGN PARAMETERS(2012 IBC/2014 OSSC) Recommended e mended Seismic Parameter Value Site Class C MCER 0.2-Second Period 0.97 g Spectral Response Acceleration, SMs MCER 1.0-Second Period 0.58 g Spectral Response Acceleration, SM, Design-Level 0.2-Second Period 0.65 g Spectral Response Acceleration, Sos Design-Level 1.0-Second Period 0.39 g Spectral Response Acceleration, So, Seismic Hazards. Based on the depth to groundwater at the site, it is our opinion the risk of liquefaction and/or cyclic softening at the site is low. Due to the relative consistency/density of the overburden soils and the presence of shallow basalt, it is our opinion the risk of earthquake-induced slope instability is low. The risk of damage by tsunami and/or seiche at the site is absent. The location of the Canby-Mollala Fault is about 5 km east of the site (Personius et al., 2003); however,the USGS does not consider the Canby-Mollala Fault to be an active, contributing source in their Probabilistic Seismic Hazard Analysis (PSHA). The USGS considers the Portland Hills Fault, located about 17 km east of the site, to be the closest crustal fault source contributing to the overall seismic hazard at the site. Unless occurring on a previously unmapped or unknown fault, the risk of fault rupture at the site is low. Earthwork General. The fine-grained soils that mantle the site are sensitive to moisture, and perched groundwater may approach the ground surface during the wet winter months. Therefore, it is our opinion earthwork can be GRU 6 completed most economically during the dry summer months,typically extending from June to mid-October. It has been our experience that the moisture content of the upper few feet of the fine-grained soils will decrease during extended warm, dry weather. However, below this depth, the moisture content of the soil tends to remain relatively unchanged and well above the optimum moisture content for compaction. As a result,the contractor must use construction equipment and procedures that reduce disturbance and softening of the subgrade soils. To minimize disturbance of the moisture-sensitive fine-grained soils, site grading can be completed using track-mounted hydraulic excavators. The excavation should be finished using a smooth- edged bucket to produce a firm, undisturbed surface. It may also be necessary to construct granular haul roads and work pads concurrently with excavation to reduce subgrade disturbance. If the subgrade is disturbed during construction, soft, disturbed soils should be overexcavated to firm soil and backfilled with structural fill. If construction occurs during wet-ground conditions, granular work pads will be required to protect the underlying fine-grained subgrade and provide a firm working surface for construction activities. In our opinion, a 12- to 18-in.-thick granular work pad should be sufficient to reduce subgrade disturbance by lighter construction equipment and limited traffic by dump trucks. Haul roads and other high- density traffic areas will require a minimum of 18 to 24 in. of fragmental rock, up to 6-in. nominal size, to reduce the risk of subgrade deterioration. The use of a geotextile fabric over the subgrade may reduce maintenance during construction. As an alternative to the use of a thickened section of crushed rock to support construction activities and protect the subgrade, the subgrade soils can be treated with cement. It has been our experience in this area that treating the subgrade soils to a depth of 12 to 14 in. with about a 6 to 8% admixture of cement overlain by 6 to 12 in. of crushed rock will support construction equipment and provide a good, all-weather working surface. Site Preparation. The ground surface within all building areas, paved areas, walkways, and areas to receive structural fill should be stripped of existing vegetation, surface organics, and loose surface soils. We anticipate stripping up to a depth of about 4 to 6 in. will likely be required within vegetated areas; however, deeper grubbing may be required to remove brush and tree roots. All trees, brush, and surficial organic material should be removed from within the limits of the proposed improvements. Excavations required to remove brush and trees should be backfilled with structural fill. Organic strippings should be disposed of off site or stockpiled on site for use in landscaped areas. Following stripping or excavation to subgrade level,the exposed subgrade should be evaluated by a qualified member of GRI's geotechnical engineering staff or an engineering geologist. Proof rolling with a loaded dump truck may be part of this evaluation. Any soft areas or areas of unsuitable material disclosed by the evaluation should be overexcavated to firm material and backfilled with structural fill. Due to the presence of very soft to soft soils near the ground surface, it should be anticipated that some overexcavation of subgrade will be required. Site Grading. Final grading across the project should provide for positive drainage of surface water away from exposed slopes to reduce the potential for erosion. Prior to placing pavement base course aggregate, subgrade should be sloped to a minimum 0.5% slope to aid in drainage. Permanent cut and fill slopes should be no steeper than 2H:1V (Horizontal to Vertical) and should be protected with vegetation to reduce GRU the risk of surface erosion due to rainfall. Seeps or springs that emerge on cut slopes may require drainage provisions depending on the actual conditions observed during construction. These provisions could include French drains, drainage blankets, and subdrains (possibly placed in utility trenches) to collect and remove water. More detailed information about site drainage is provided in the Site Drainage subsection of this report. Site Drainage. Due to site topography,there is a risk of surface water sheeting off the hillside during periods of intense or prolonged precipitation. In our opinion, construction of a seepage cutoff trench to intercept surface water and shallow, perched groundwater should be considered to reduce the risk of surface water impacting the building and other associated improvements. To be most effective, the cutoff trenches should be positioned uphill of improvements and in low areas on site and should be excavated to the top of the underlying basalt rock. Typical cutoff trench drainage details are provided on Figure 3. The figure shows a perforated drain pipe backfilled with clean, drain rock that has less than 2% passing the No. 200 screen (washed analyses) and is placed within an envelope of a non-woven geotextile fabric to serve as a filter between the drain rock and the adjacent soil. Bedding the pipe in at least 6 in. of drain rock and providing a positive slope for the pipe to drain will reduce the future risk of silt and fine-grained sand accumulating in the pipe. Water collected in perforated drains should be discharged into approved stormwater inlets by solid, non-perforated piping. If significant groundwater seepage is encountered, it may be prudent to install more than one perforated drain pipe. In our opinion,these drainage improvements will increase the overall stability of the site. GRI should review the final site drainage plans developed by the civil engineer once they become available to evaluate the effectiveness of the site drainage system. Excavation General. We estimate excavations on the order of 5 to 20 ft will be required to establish final site grades, and the depth of utility excavations may be on the order of 5 to 10 ft. The method of excavation and design of excavation support are the responsibility of the contractor and subject to applicable local,state,and federal safety regulations, including the current Occupational Safety and Health Administration (OSHA) excavation and trench safety standards. The means, methods, and sequencing of construction operations and site safety are also the responsibility of the contractor. The information provided below is for the use of our client and should not be interpreted to mean we are assuming responsibility for the contractor's actions or site safety. Groundwater Management. Depending on the time of year the work is completed, perched groundwater may be encountered in the excavations. Groundwater seepage, running soil conditions, and unstable excavation sidewalls or excavation subgrades, if encountered during construction, will require dewatering of the excavation and sidewall support. The impact of these conditions can be reduced by completing excavations during the summer months, when perched groundwater levels are lowest, and by limiting the depths of the excavations. We anticipate perched groundwater inflow, if encountered, can generally be controlled by pumping from sumps. To facilitate dewatering, it will be necessary to overexcavate the base of the excavation to permit installation of a granular working blanket. We estimate the required thickness of the granular working blanket will be on the order of 1 ft, or as required to maintain a stable excavation base. The actual required depth of overexcavation will depend on the conditions exposed in the excavations and the effectiveness of GRU 8 ). the contractor's dewatering efforts. The thickness of the granular blanket must be evaluated based on field observations during construction. We recommend the use of relatively clean, free- draining material,such as 2-to 4-in.-minus crushed rock, for this purpose. The use of a geotextile fabric over the excavation base will assist in subgrade stability and dewatering. Temporary Excavations. The inclination of temporary excavation slopes will depend, in part,on the perched groundwater conditions encountered at the time of construction and the contractor's ability to control these conditions. In this regard, we anticipate temporary excavation slopes can be cut at 1 H:1 V to a maximum depth of 15 ft if groundwater levels are maintained at least 2 ft below the bottom of the excavation. If the excavation depth exceeds 15 ft, the temporary excavation slopes should be cut at 1.5H:1V or flatter. Flatter slopes will be necessary if significant seepage conditions are encountered. Some minor amounts of sloughing,slumping,or running of temporary slopes should be anticipated shortly after groundwater seepage occurs. A blanket of relatively clean, well-graded crushed rock placed on the slopes may be required to reduce the risk of raveling-soil conditions if temporary excavation slopes encounter perched groundwater. We recommend the use of relatively clean,free-draining material, such as 2-to 4-in.-minus crushed rock,for this purpose. The thickness of the granular blanket should be evaluated based on actual conditions but would likely be in the range of 12 to 24 in. In our opinion, the short-term stability of temporary slopes will be adequate if surcharge loads due to construction traffic, vehicle parking, material laydown, etc., are maintained an equal distance to the height I of the slope away from the top of the open cut. Other measures that should be implemented to reduce the risk of localized failures of temporary slopes include: 1) using geotextile fabric to protect the exposed cut slopes from surface erosion;2) providing positive drainage away from the tops and bottoms of the cut slopes; 3) constructing and backfilling walls as soon as practical after completing the excavation; 4) backfilling overexcavated areas as soon as practical after completing the excavation; and 5) periodically monitoring the area around the top of the excavation for evidence of ground cracking. It must be emphasized that following these recommendations will not guarantee sloughing or movement of the temporary cut slopes will not occur; however, the measures should serve to reduce the risk of a major slope failure. It should be realized, however, that blocks of ground and/or localized slumps may tend to move into the excavation during construction. Utility Excavations. In our opinion, there are three major considerations associated with design and construction of new utilities: 1) Provide stable excavation side slopes or support for trench sidewalls to minimize loss of ground. 2) Provide a safe working environment during construction. 3) Minimize post-construction settlement of the utility and ground surface. According to current OSHA regulations,the majority of the fine-grained soils encountered in the explorations may be classified as Type B. In our opinion, trenches less than 4 ft deep that do not encounter groundwater may be cut vertically and left unsupported during the normal construction sequence, assuming trenches are excavated and backfilled in the shortest possible sequence. Excavations more than 4 ft deep should be laterally supported or alternatively provided with side slopes of 1 H:1 V or flatter. In our opinion, adequate GRU 9 lateral support may be provided by common methods,such as the use of a trench shield or hydraulic shoring systems. Drainage pipes can be installed at the base of select trenches to help with site drainage and reduce the risk of perched groundwater or surface water inflow concentrating in the trench backfill during the wet season. The drainage pipe should consist of a 4-in.-diameter perforated PVC pipe wrapped in a non-woven geotextile and placed in the granular backfill near the bottom of the trench. A utility pipe in a typical cutoff trench detail is provided on Figure 3. The collected water should be discharged to approved stormwater inlets by solid, non-perforated piping. Rock Excavation. We anticipate shallow basalt may be encountered in excavations completed to found the new building additions, retaining structures, and/or in utility excavations. The hardness, jointing, and weathering of the underlying basalt will be highly variable depending on location and depth. Based on our observations during test-pit excavations, we anticipate it will be possible to complete excavation of zones of highly fractured or weathered basalt by ripping with a large bulldozer and/or a large track-mounted hydraulic excavator equipped with a rock bucket and rock teeth. However, it should be anticipated that some rock chipping, mechanical or chemical splitting, or blasting will be necessary to remove harder zones of less- weathered and fractured rock, if encountered. Blasting may not be permitted at the site and should be discussed with the project team prior to considering this method. Project plans, specifications,and bid items should address the uncertainty associated with encountering basalt in excavations completed on site. At a minimum, we recommend the project bid items include a unit price per cubic yard of rock excavation. Structural Fill General. We anticipate up to 15 ft of structural fill may be required to achieve finished floor elevation for the structure and finished grades for the associated improvements. In general, structural fills should consist of imported or on-site, organic-free soils and should extend a minimum horizontal distance of 5 ft beyond the edge of new foundations and 1 ft beyond the limits of ancillary improvements, such as the edge of new pavements. Where fills are to be placed on existing slopes steeper than about 5H:1V, the area to be filled should be terraced or benched to provide a relatively level surface for fill placement. Typical benching requirements are illustrated on Figure 4. Onsite, Fine-Grained Fill. The use of on-site, fine-grained soils for structural fill material is typically limited to the dry summer months, when the moisture content of these soils can be controlled to within about 3% of optimum. However, the natural moisture content of the on-site soils will probably exceed the optimum moisture content throughout the majority of theyear; therefore, some aeration and drying will be required g 1 �' ►y� g q to meet the requirements for proper compaction. The required drying can best be accomplished by spreading the material in thin lifts and tilling. Drying rates are dependent on weather factors, such as wind, temperature, and relative humidity. Fine-grained soils used as structural fill should be placed in 8-in.-thick lifts (loose) and compacted with a segmented-pad or sheepsfoot roller to at least 95% of the maximum dry density as determined by ASTM International (ASTM) D698. If fine-grained soils are not compacted at a moisture content within about 3% of optimum,the specified density cannot be achieved and the fill material will be relatively weak and possibly compressible. On-site, fine-grained soils and site strippings free of debris may be used as fill in non-structural landscaped areas. These materials should be placed at about 90% of the maximum dry density as determined by GRU10 ASTM D698. The moisture contents of soils placed in landscaped areas are not as critical as the moisture contents of fill placed in building and pavement areas, provided construction equipment can effectively handle the materials. Imported Granular Fill. During wet conditions, imported granular material would be most suitable for construction of the structural fills. Granular material, such as sand, sandy gravel, or fragmental rock with a maximum size of up to 2 in. and less than 5% passing the No. 200 sieve (washed analysis)would be suitable structural fill material. Granular fill should be placed in lifts and compacted with vibratory equipment to at least 95% of the maximum dry density determined in accordance with ASTM D698. Appropriate lift thicknesses will depend on the type of compaction equipment used. For example, if hand-operated vibratory plate equipment is used, lift thicknesses should be limited to 6 to 8 in. If smooth-drum, vibratory rollers are used, lift thicknesses up to 12 in. are appropriate, and if backhoe-or excavator-mounted vibratory plates are used, lift thicknesses of up to 2 ft may be acceptable. Cement-Amended Fill. As an alternative to importing granular fill, cement may be mixed with fine-grained soils to facilitate fill placement during wet conditions. The amount of cement required will depend on the moisture, clay, and organic contents of the soil and must be determined at the time of construction. Typical admixtures of 5 to 8% cement, based on the dry weight of the treated soil, have been successfully implemented in the project area. Cement treatment principally serves to hydrate excessive moisture and significantly improves the strength properties of a fine-grained subgrade or structural fill. Treatment is accomplished by spreading a measured quantity of cement onto the surface and tilling 12 to 16 in. into the subgrade or structural fill lift using specialized equipment. The treated soils are subsequently compacted with segmented-pad rollers and finished with graders and smooth, steel-drum vibratory rollers. Cement- treated soils are typically cured 3 to 5 days to maximize their strength gain prior to being trafficked by equipment or placement of granular base course. Utility Trench Backfill. All utility trench excavations within building, hardscape,and pavement areas should be backfilled with relatively clean, granular material, such as sand, sandy gravel, or crushed rock of up to 11I2-in. maximum size and having less than 5% passing the No. 200 sieve (washed analysis). The bottom of the excavation should be thoroughly cleaned to remove loose materials and the utilities should be underlain by a minimum 6-in. thickness of bedding material. The granular backfill material should be compacted to at least 95% of the maximum dry density as determined by ASTM D698 in the upper 5 ft of the trench and at least 92% of this density below a depth of 5 ft. The use of hoe-mounted vibratory-plate compactors is usually most efficient for this purpose. Flooding or jetting as a means of compacting the trench backfill should not be permitted. Areal Fill Settlement. We anticipate fills up to 10 ft in height will be placed in the southern half of the building footprint to achieve final site grades. Areal settlement will occur due to placement of new fills and consolidation of the underlying soils. Settlement studies were completed using the computer program Settle3D by Rocscience, Inc. Based on our studies, we estimate the total consolidation settlement due to placement of 10 ft of fill will be on the order of 1 in. It is our opinion that, at a minimum, settlement due to primary consolidation should be allowed to occur prior to construction of overlying foundations, slab-on- grade floors, and hardscapes and installation of utilities. We anticipate the majority of this settlement will occur during placement of the fill; however, we recommend waiting at least 4 weeks following construction of the design fill height to construct the overlying improvements. GRU11 Foundation Support Structural information provided by Catena Consulting Engineers, Inc., the project structural engineer, indicates the new school building will have maximum wall and column loads on the order of 3 kips/ft and 90 kips, respectively. In our opinion,the proposed structural loads can be supported on conventional spread and wall footings in accordance with the following design criteria. All footings should be established in firm, undisturbed, native soil or compacted structural fill. The base of all new footings should be established at a minimum depth of 18 in. below the lowest adjacent finished grade. The footing width should not be less than 24 in. for isolated column footings and 18 in. for wall footings. Excavations for all foundations should be made with a smooth-edged bucket, and all footing subgrades should be observed by a member of GRI's geotechnical engineering staff. Soft or otherwise unsuitable material encountered at foundation subgrade level should be overexcavated and backfilled with granular structural fill. Due to the presence of soft soils near the ground surface, it should be anticipated that some overexcavation of subgrade may be required. We anticipate soft soils and shallow basalt may be encountered in excavations completed to found the new building additions. To provide uniform support,we recommend all foundations be underlain by a minimum 12-in. thickness of compacted crushed rock due to the potentially variable footing support conditions. Relatively clean, 11/2-or 3/4-in.-minus crushed rock is suitable for this purpose. In addition, large excavation equipment or excavation methods,such as chipping,splitting,chemical rock breaking,or blasting,will likely be required if basalt is encountered in foundation excavations. More detailed information about rock excavation methods and techniques is provided in the Rock Excavation subsection of this report. Footings established in accordance with these criteria can be designed on the basis of an allowable soil bearing pressure of 3,000 psf. This value applies to the total of dead load and/or frequently applied live loads and can be increased by one-third for the total of all loads: dead, live, and wind or seismic. We estimate the total static settlement of spread and wall footings designed in accordance with the recommendations presented above will be less than 1 in. for footings supporting column and wall loads of up to 90 kips and 3 kips/ft, respectively. Differential static settlements between adjacent, comparably loaded footings on similar subgrade conditions should be less than half the total settlement. Horizontal shear forces can be resisted partially or completely by frictional forces developed between the base of the footings and the underlying soil and by soil passive resistance. The total frictional resistance between the footing and the soil is the normal force times the coefficient of friction between the soil and the base of the footing. We recommend an ultimate value of 0.40 for the coefficient of friction for footings cast on granular material. The e normal force is the sum of the vertical forces (dead load plus real live load). If additional lateral resistance is required, passive earth pressures against embedded footings can be computed on the basis of an equivalent fluid having a unit weight of 250 pcf. This design passive earth pressure would be applicable only if the footing is cast neat against undisturbed soil or if backfill for the footings is placed as granular structural fill and assumes up to 1/2 in. of lateral movement of the structure will occur in order for the soil to develop this resistance. This value also assumes the ground surface in front of the foundation is horizontal, i.e., does not slope downward away from the toe of the footing, or has at least 4 ft of horizontal distance from the embedded portion of the footing to the face of any permanent slope up to 3H:1V. For foundations constructed on slopes up to 3H:1V, the passive pressure against the embedded portion of the foundation should be reduced to 100 pcf. G ®012 ... ........,.... ......... .. .,.r.e r s.+Rrssxauautrsatili.eestisssiRUUaM:<ete.:ra.,.J.tl.xueaH i+wfduid#uawwiliaa lueraiex+ur ra..,...r. , ,.r,,.,ar .a,ua,ua rl3cJrrJJ ailMt.rbrl fYrirrxauat x4a.xliia ,a.rueiiulniMbYFNNNf{4 YWleaelari Subdrainage/Floor Support To provide a capillary break and reduce the risk of damp floors, slab-on-grade floors established at or above adjacent final site grades should be underlain by a minimum 8 in. of free-draining,clean, angular rock. This material should consist of angular rock such as 1' -to 3/4-in. crushed rock with less than 2% passing the No. 200 sieve (washed analysis) and should be capped with a 2-in.-thick layer of compacted, 3/4-in.-minus crushed rock to improve workability. The slab base course section should be placed in one lift and compacted to at least 95% of the maximum dry density (ASTM D698) or until well-keyed. In our opinion, it is appropriate to assume a coefficient of subgrade reaction, k, of 175 pci to characterize the subgrade support for point loading with 10 in.of compacted crushed rock beneath the floor slab. In areas where floor coverings will be provided, or moisture-sensitive materials stored, it would be appropriate to also install a vapor-retarding membrane. The membrane should be installed as recommended by the manufacturer. We understand the building will be benched into the hillside and portions of the building will be established below final site grades. In our opinion,structures such as floors and loading ramps that are established below the final and existing site grades should be provided with a subdrainage system to reduce the potential for hydrostatic pressure and the risk of groundwater entering through embedded walls and floor slabs. In addition, a foundation drain should be installed around the perimeter of the building to collect water that could potentially infiltrate beneath the foundations and should discharge to an approved storm drain. Typical subdrainage details for embedded structures and footings are shown on Figure 5. The figure shows perimeter subdrains to drain embedded walls and/or footings, and an interior granular drainage blanket beneath the concrete floor slab, which is drained by a system of subslab drainage pipes. All groundwater collected should be drained by gravity or pumped from sumps into the stormwater disposal facility. If the water is pumped, an emergency power supply should be included to prevent flooding due to a power loss. GRI should review the final subdrainage plans developed by the civil engineer for the building once they become available to evaluate the effectiveness of the subdrainage system. Retaining/Embedded Walls General. Walls with a maximum height of about 10 to 15 ft will be required for construction of the partially embedded lower level, and site retaining walls up to 20 ft in height will be required to retain finished grades for the drive lanes, parking lots, and other ancillary improvements. We anticipate the embedded walls will be cast-in-place and supported on the building foundations and the retaining walls will be conventional cantilever walls, such as cast-in-place walls or segmented block walls, or soil nail walls. We should be contacted if other types of retaining walls are to be considered for this project. GRI should review the final plans developed by the wall designer once they become available and complete global external stability analyses on representative cross sections of the planned retaining walls. Lateral Earth Pressures. Design lateral earth pressures for retaining/embedded walls depend on the type of construction, i.e.,the ability of the wall to yield. Possible conditions are: 1) a wall that is laterally supported at its base and top and therefore unable to yield to the active state; and 2) a retaining wall, such as a typical cantilever or gravity wall, that yields to the active state by tilting about its base. A conventional basement wall and cantilever retaining wall are examples of non-yielding and yielding walls, respectively. G 'RA 13 For horizontal backfill,yielding and non-yielding walls may be designed on the basis of equivalent fluid unit weights of 35 and 55 pcf, respectively. To account for seismic loading, the earth pressure should be increased by 8 and 16 pcf for yielding and non-yielding walls, respectively, with horizontal backfill. For up to a 3H:1V sloping backfill, yielding walls may be designed based on the basis of an equivalent fluid unit weight of 55 pcf and should be increased by 23 pcf to account for seismic conditions. These earth pressures assume the walls are fully drained, i.e., hydrostatic pressure cannot build up on the back of the wall. This results in a triangular distribution with the resultant acting at 1/3H up from the base of the wall, where H is the height of the wall in feet. Additional lateral loading due to surcharge loads can be evaluated using the criteria shown on Figure 6. The lateral earth pressure criteria presented above are appropriate if the retaining/embedded walls are fully drained. Although the permanent groundwater level likely occurs at depth in the fractured basalt that underlies the site, perched groundwater may occur within the shallow fine-grained soils and existing utility trenches during periods of prolonged or intense precipitation. We recommend installation of a permanent drainage system behind all the retaining/embedded walls. The drainage system can either consist of a drainage blanket of crushed rock or continuous drainage panels between the retained soil/backfill and the face of the wall. The drainage blanket should have a minimum width of 12 in. and consist of crushed drain rock that contains less than 2% fines content (washed analysis). A typical drainage system for embedded walls is shown on Figure 5. The drainage blanket or drainage panels should extend to the base of the wall, where water should be collected in a perforated pipe and discharged to a suitable outlet, such as a sump or approved storm drain. In addition, the wall design should include positive drainage measures to prevent ponding of surface water behind the top of the wall. Overcompaction of backfill behind walls should be avoided. Heavy compactors and large pieces of construction equipment should not operate within 5 ft of any retaining wall to avoid the buildup of excessive lateral earth pressures. Compaction close to the walls should be accomplished with hand-operated vibratory plate compactors. Overcompaction of backfill could significantly increase lateral earth pressures behind walls and cause damage to cast-in-place concrete retaining walls. Conventional Walls. Foundation design and subgrade preparation for conventional, cast-in-place or segmented block walls should conform to the recommendations provided in the Foundation Support section of this report. We recommend embedding the toe of conventional retaining walls at least 1.5 ft below the ground surface in front of the wall. For conventional walls constructed on a slope of up to 3H:1V, we recommend the toe of the wall be provided a minimum of 2.5 ft of embedment. To provide more uniform support, conventional retaining walls should be founded on a minimum 6-in.-thick section of compacted crushed rock. Permanent improvements will likely be located within the zone of wall backfill; therefore, we recommend all conventional wall backfill, excluding the drainage blanket, consist of relatively clean, granular structural fill with a maximum size of about 1'/z in. and not more than about 5% passing the No. 200 sieve (washed analysis). Typical design values for crushed rock described above are a wet (total) density,yr, of 130 pcf; an effective angle of internal friction, 4',of 35°; and an effective cohesion, c', of 0 psf. We recommend a minimum reinforcement length for segmented block walls of no less than 0.8 times the height of retained backfill plus the equivalent height of uniformly applied surcharge pressure at the top of c! O14 the backfill. The actual reinforcement length should be evaluated by the wall designer. It should be understood that cantilever walls must undergo some lateral deformation to mobilize the active earth pressures and foundation resistance or shear strength of the MSE reinforcement typically used in segmented block walls. Based on our experience, lateral deformations on the order of about 1/2 and 1 in. are typical for 20-ft-high MSE and cast-in-place concrete walls, respectively. The wall designer should evaluate the potential for lateral deformation of the selected wall design. Soil Nail Walls. We anticipate a soil nail wall may be used to retain the planned cut near the northern property boundary. Soil nail walls can be designed with relatively steep, near-vertical faces using reinforced shotcrete facing between the individual soil nails, which are typically installed in drilled holes and grouted into place. Soil nail walls typically have proprietary design and installation procedures developed by a specialty contractor to satisfy a performance-based specification. However, soil nail walls should be designed, constructed, and tested in substantial conformance with the guidelines provided in the Federal Highway Administration (FHWA) Soil Nail Walls Reference Manual (FHWA-NHI-14-007). Based on a review of the subsurface information for the site, we anticipate soil nail installation would primarily encounter residual soil and decomposed basalt. In our opinion, it is appropriate for preliminary planning to assume the following soil properties for the soil nail design. PRELIMINARY SOIL PROPERTIES FOR SOIL NAIL DESIGN Static Conditions Seismic Conditions Moist Unit Moisture Effective Effective Stress Undrained Soil Type Weight,pcf Content,% Friction Angle,4)' Cohesion,psf Shear Strength,psf Clayey SILT to Silty CLAY 120 30 26° 250 500 (Residual Soil) Silty SAND 125 40 38° 0 Same as Static (Decomposed Basalt) It should be understood that a soil nail wall must undergo some lateral deformation to mobilize the shear strength of the nails. Based on our experience, lateral deformations on the order of about 1/2 in. are typical for a 20-ft-high soil nail wall. The wall designer can consider stressing the soil nails to reduce wall deformation. Pavement Design We anticipate the bus loop pavement will be subjected to bus, automobile, and light truck traffic, and the parking areas will be subjected primarily to automobile and light truck traffic, with occasional heavy truck traffic. We anticipate the majority of the site will be paved with AC pavement; however, areas subjected to repeated heavy-truck traffic, such as trash-enclosure and service areas, may be paved with PCC pavement. Traffic estimates for the roadways and parking areas are presently unknown. Based on our experience with similar projects and subgrade soil conditions, we recommend the following pavement sections. GRfl 15 RECOMMENDED AC PAVEMENT SECTIONS Pavement Type Traffic Loadin CRB AC g Thickness,in. Thickness,in. AC Areas Subject to School-Bus 14 Traffic(Bus Loop) Areas Subject to Primarily AC Automobile Traffic(Service Road 12 4 and Vehicle Drive Lanes) AC Areas Subject to Automobile 8 3 Parking(Parking Stalls) Areas Subject to Repeated PCC Heavy Truck Traffic(Trash 6 6 Enclosure and Service Areas) Note: The recommended pavement sections should be considered minimum thicknesses and underlain by a woven geotextile fabric. It should be assumed that some maintenance will be required over the life of the pavement (15 to 20 years). The recommended pavement sections are based on the assumption that pavement construction will be accomplished during the dry season and after construction of the building has been completed. If wet- weather pavement construction is considered, it will likely be necessary to increase the thickness of crushed- rock base (CRB) course to support construction equipment and protect the subgrade from disturbance. The indicated sections are not intended to support extensive construction traffic, such as fork lifts, dump trucks and concrete trucks. Pavements subject to construction traffic may require repair. For the above-indicated sections,drainage is an essential aspect of pavement performance. We recommend all paved areas be provided positive drainage to remove surface water and water within the base course. This will be particularly important in cut sections or at low points within the paved areas, such as at catch basins. Effective methods to prevent saturation of the base course materials include providing weep holes in the sidewalls of catch basins, subdrains in conjunction with utility excavations, and separate trench drain systems. To ensure quality materials and construction practices,we recommend the pavement work conform to Oregon Department of Transportation standards. Prior to placing base course materials, all pavement areas should be proof rolled with a fully loaded, 10-cy dump truck. Any soft areas detected by the proof rolling should be overexcavated to firm ground and backfilled with compacted structural fill. Provided the pavement section is installed in accordance with the recommendations provided above, it is our opinion the site-access areas will support infrequent traffic by an emergency vehicle having a gross vehicle weight (GVW) of up to 75,000 lbs. For the purposes of this evaluation, "infrequent" can be defined as once a month or less. On-Site Disposal of Stormwater The unfactored, field-measured infiltration rate for the residual soils that mantle the site is 0 in./hour; therefore, it is our opinion the near-surface fine-grained soils do not meet the requirements for on-site stormwater disposal. GR 16 Considerations for Adjacent Property We understand the project team would like to consider stockpiling spoils from on-site excavations on the property located immediately east of the project site. For the purpose of this report, the project site is designated Lot 1 and the property located immediately east of Lot 1 is designated Lot 2. In our opinion, any spoils stockpiled on Lot 2 should be prepared, placed, and compacted as structural fill in accordance with the recommendations provided in the Structural Fill section of this report. The ground surface in the stockpiled area should be stripped of existing vegetation, surface organics, and loose surface soils in accordance with the recommendations provided in the Earthwork section of this report. Consideration should be given to the location and dimensions of the stockpile and the time and effort required to strip the ground surface of vegetation and place the excavation spoils as structural fill. In our opinion, it would be prudent to discuss stockpiling excavation spoils on Lot 2 with the property owner prior to considering this option. DESIGN REVIEW AND CONSTRUCTION SERVICES We welcome the opportunity to review and discuss construction plans and specifications for this project as they are being developed. In addition, GRI should be retained to review all geotechnical-related portions of the plans and specifications to evaluate whether they are in conformance with the recommendations provided in our report. To observe compliance with the intent of our recommendations,the design concepts, and the plans and specifications, we are of the opinion that all construction operations dealing with earthwork and foundations should be observed by a GRI representative. Our construction-phase services will allow for timely design changes if site conditions are encountered that are different from those described in our report. If we do not have the opportunity to confirm our interpretations, assumptions, and analyses during construction, we cannot be responsible for the application of our recommendations to subsurface conditions different from those described in this report. LIMITATIONS This report has been prepared to aid the architect and engineer in the design of this project. The scope is limited to the specific project and location described herein, and our description of the project represents our understanding of the significant aspects of the project relevant to the design and construction of the new foundations and floors. In the event any changes in the design and location of the project elements as outlined in this report are planned, we should be given the opportunity to review the changes and modify or reaffirm the conclusions and recommendations of this report in writing. The conclusions and recommendations submitted in this report are based on the data obtained from the explorations made at the locations indicated on Figure 2 and other sources of information discussed in this report. In the performance of subsurface investigations, specific information is obtained at specific locations at specific times. However, it is acknowledged that variations in soil conditions may exist between exploration locations. This report does not reflect any variations that may occur between these explorations. The nature and extent of variation may not become evident until construction. If during construction, subsurface conditions differ from those encountered in the explorations, we should be advised at once so that we can observe and review these conditions and reconsider our recommendations where necessary. GR 17 Please contact the undersigned if you have any questions. Submitted for GRI, eiktO PROFFS 4 N e s/�2 cti 1/4, 113281 4' r i f. Is., ON AY&SLEY SpAtyb .` I l Renews 06/2020 A. Wesley Spang, PhD, PE, GE Nicholas M. Hatch, PE Marissa Rauthause, EIT Principal Senior Engineer Engineering Staff This document has been submitted electronically. 1 References ASCE 7 Hazard Tool,2017-2018,accessed 1/3/19 from ASCE website: https://asce7hazardtool.online/. Madin,I. P.,2004, Preliminary digital geologic compilation map of the greater Portland urban area,Oregon:Oregon Department of Geology and Mineral Industries,Open-File Report 0-04-02,scale 1:24,000. Personius,S.F., Dart,R. L.,Bradley, Lee-Ann,and Haller, K.M.,2003,Map and data for Quaternary faults and folds in Oregon: U.S. Geological Survey Open-File Report 03-095. Snyder, D. T., 2008, Estimated depth to ground water and configuration of the water table in the Portland, Oregon area: U.S. Geological Survey Scientific Investigations Report 2008-5059,40 p. U.S.Geological Survey(USGS), Unified hazard tool,Conterminous U.S.2014(v4.0x),accessed 01/10/19 from USGS website: https://earthquake.usgs.gov/hazards/interactive/. U.S.Geological Survey,2018, U.S.Seismic Design Maps lookup by latitude,longitude,accessed 01/10/19 from USGS website: https://earthquake.usgs.gov/designmaps/us/application.php. G RIM18 l i Kinton ti� 1--"A-,- L. I) V , -, _ q lo �. -2 z- /`.a ( h ion ) o /- r 4, , ,_, - 14 ; : ' . , _.„,15 ' -- / - a ./".*.. .N.(, \,j ' a § 'U7, (3. - - / ', , ! ( 14_, ''''-' L, ,.e, , , f_ m BULL MOUNTAIN RD 1 Q __ ' 't ./_. �y SW DEKALB ST -SW BURGUNDY ST 3 s k ' i 1h._- BULL 3 � - f I ! lAIiOUNTAIN _ ,/ r j a . >q is _,zit,,,,,, J ) _ _ �V 1 taalUtlT�' Vs 2 ( � _ ( T-Z 50 Q SW WOODHUE ST ,\ i (((SwEINISLN _� �i, �\ aV teaiikkii . A SITE ,-- SW CASICH LN / --'? r�._.,._ __ \ / 0 Q. 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APR.2019 10B NO 5970-K FIG 2 /77 NON-WOVEN GEOTEXTILE FABRIC GRANULAR MATERIAL(2 IN.MAX.)WITH LESS THAN 5%PASSING THE NO.200 SIEVE(WASHED ANALYSIS) UTILITY PIPE MAY BE PLACED IN V•'•i•••'•i!• ii��T ro•stPhi1l CUTOFF TRENCH *1 I.•W • iato •; —6 IN.(MIN.) • A 4-IN.-DIAMETER PERFORATED DRAIN PIPE, SLOPE TO DRAIN G R U TIGARD-TUALATIN SCHOOL DISTRICT ART RUTKIN ELEMENTARY SCHOOL CUTOFF TRENCH DRAINAGE DETAIL APR.2019 JOB NO.5970-K FIG.3 CUT SLOPE EXISTING GROUND SURFACE 2(MIN.) FILL SLOPE 8 FT(MIN.) > 2(MIN.) 1 4 FT(MAX.)MA BENCHES(TYP.) 5 FT(MIN.) > < G R TIGARD-TUALATIN SCHOOL DISTRICT ART RUTKIN ELEMENTARY SCHOOL TYPICAL DETAIL FOR FILLING ON SLOPES APR.2019 JOB NO.5970-K FIG.4 I � 3/4-IN.-MINUS CRUSHED ROCK WITH /SEAL WITH ON-SITE I /LESS THAN 5%PASSING NO.200 SIEVE IMPERVIOUS MATERIAL / (WASHED ANALYSIS) SLOPE TO DRAIN T 21N.1 ,•, CONCRETE SLAB a '• , o6. $y.•4y.�7y VARIES VAPOR-RETARDING MEMBRANE SYSTEM • Io' y.. �.pr Y(2 IN.MIN.) BIN.(MIN.i (SEE NOTE I) i�I.:i t.0.- ' I .IIII1 i • 4� VARIES(2 IN.MIN.) I -°• T GRANULAR BACKFILL COMPACTED I 1 TO ABOUT 95%OF THE MAXIMUM Y< 1ET) '�• DRY DENSITY AS DETERMINED BY (MIN. ASTM D ) SEE DETAIL'A'FOR TYPICAL ROCK OF UP TO 2-IN.SIZE WITH AJN-DIAMETER PERFORATED DRAIN PIPES I _ UNDERSLAB RECOMMENDATIONS NOT MORE THAN 2%PASSING THE NO.200 SIEVE(WASHED ANALYSIS( ARE TYPICALLY PLACED ON 20•FT CENTERS AND SLOPED TO DRAIN(SEE NOTE 2) TEMPORARY----- CONSTRUCTION �a. SLOPE I DETAIL'A' NOT TO SCALE 11/2 TO1/4 GRAVEL WITH LESS THAN 2%PASSING THE Na200 SIEVED (WASHED ANALYSIS) UNDERSLAB DRAIN \4IN-DIAMETER PERFORATED PLASTIC DRAIN PIPE,SLOPE TO DRAIN NOTES: 1) A VAPOR-RETARDING MEMBRANE SYSTEM IS RECOMMENDED FOR MOISTURE-SENSITIVE AREAS AND SHOULD BE INSTALLED IN ACCORDANCE WITH MANUFACTURER'S RECOMMENDATIONS. 2) INTERNAL 4-IN-DIAMETER PERFORATED DRAIN PIPES ARE TYPICALLY PERIMETER DRAIN NOT NECESSARY IN THOSE AREAS WHERE THE FINISH FLOOR WILL BE ABOVE EXISTING SITE GRADES. OE� TIGAR0.TUALATIN SCHOOL DISTRICT ART RUTKIN ELEMENTARY SCHOOL TYPICAL SUBDRAINAGE DETAILS APR.2019 LOB NO.5970-K FIG.5 < X=mH > LINE LOAD,QL STRIP LOAD,q f/ n n A /3/2 Z=nH NE. For m S 0.4: V _ QL 0.2n vh H (0.16+ n2)2 WFor m>0.4: hQh = Qr 1.28m2n 7h= : SINPcOs2 ( Tr H (m2+n2)2 (/3 in radians) LINE LOAD PARALLEL TO WALL STRIP LOAD PARALLEL TO WALL < X=mH > POINT LOAD,Qp A A g/ / Z=nH MEP For m S 0.4: V -11-A1 ah = Qp 0.28n2 H2 (0.16+n2)3 For m>0.4: Q ah = Qp 1.77m2n2 jh H2 (m2+ n2)3 a'h=a h COS2(1.10) NOTES: 0 ah A 1. THESE GUIDELINES APPLY TO RIGID WALLS WITH POISSON'S 0 // O RATIO ASSUMED TO BE 0.5 FOR BACKFILL MATERIALS. 2. LATERAL PRESSURES FROM ANY COMBINATION OF ABOVE a,h LOADS MAY BE DETERMINED BY THE PRINCIPLE OF SUPERPOSITION. X=mH > DISTRIBUTION OF HORIZONTAL PRESSURES VERTICAL POINT LOAD G R U TIGARD-TUALATIN SCHOOL DISTRICT ART RUTKIN ELEMENTARY SCHOOL SURCHARGE-INDUCED LATERAL PRESSURE APR.2019 JOB NO.5970-K FIG.6 APPENDIX A Field Explorations and Laboratory Testing APPENDIX A FIELD EXPLORATIONS AND LABORATORY TESTING FIELD EXPLORATIONS Subsurface materials and conditions at the site were investigated on December 13 and 14, 2018, and April 3 and 4, 2019, with 13 borings, designated B-1 through B-13, six test pits, designated TP-13 though TP-18, and six Kessler Dynamic Cone Penetration (DCP) probes, designated DCP-1 through DCP-6. The approximate locations of the explorations completed for this investigation are shown on Figure 2. Logs of the borings and test pits are provided on Figures 1 A throughexploration 16A. The field ex lora gp t work was coordinated and documented by an experienced member of GRI's geotechnical engineer staff, who maintained a log of the materials and conditions disclosed during the course of work. Borings Borings, designated B-1 through B-13, were advanced to depths of about 6.5 to 32 ft below existing site grades. Seven borings were completed with mud-rotary drilling techniques,and six borings were completed with hollow-stem auger drilling techniques. The borings were completed using a CME 850 track-mounted drill rig provided and operated by Western States Soil Conservation, Inc., of Hubbard, Oregon. Disturbed samples of soil and decomposed rock were typically obtained from the borings at 2.5-ft intervals of depth in the upper 15 ft and at 5-ft intervals below this depth. Standard Penetration Tests (SPT) were conducted at the time of sampling by driving the sampler into the soil a distance of 18 in. using a 140-lb hammer dropped 30 in. The number of blows required to drive the sampler the last 12 in. is known as the Standard Penetration Resistance, or SPT N-value. Samples obtained from the borings were placed in airtight jars and returned to our laboratory for further classification and testing. In addition, relatively undisturbed soil samples were collected by pushing a 3-in.-O.D. Shelby tube into the undisturbed soil a maximum of 24 in. using the hydraulic ram of the drill rig. The soil in the Shelby tubes was extruded in our laboratory and Torvane or undrained shear strength measurements were recorded. Where drilling refusal was encountered within the depth of interest, samples of basalt were obtained using HQ rock coring techniques. The core samples were placed in boxes and returned to our laboratory for further examination and testing. Logs of the borings are provided on Figures 1A through 13A. Each log presents a descriptive summary of the various types of materials encountered in the boring and notes the depths at which the materials and/or characteristics of the materials change. To the right of the descriptive summary, the numbers and types of samples are indicated. Farther to the right, SPT N-values are shown graphically, along with the natural moisture contents, Torvane shear strength values, and percent passing the No. 200 sieve, where applicable. The terms and symbols used to describe the materials encountered in the borings are defined in Tables 1A and 2A and the attached legend. A photograph of the core boxes is provided on Figure 23A. Test Pits Test pits, designated TP-13 through TP-18, were advanced to depths of about 11.5 to 18.5 ft using a CAT 326F excavator provided and operated by Benchmark Contracting, Inc., of Lake Oswego, Oregon. Torvane shear-strength values were obtained in test pit sidewalls where the material consisted of fine-grained soils. Logs of the test pits are provided on Figures 14A through 19A. Each log presents summary of the various G RQA-1 types of materials encountered in the test pits and notes the depth at which the materials and/or characteristics of the materials change. To the right of the summary, Torvane shear-strength values are shown graphically. The terms and symbols used to describe the materials encountered in the test pits are defined in Tables 1A and 2A and the attached legend. Photographs of the test pits were taken following completion and are provided on Figures 24A and 25A. DCP Probes Six DCP probes, designated DCP-1 through DCP-6, were advanced to a depth about 3 ft below the ground surface using a Kessler DCP manufactured by KSE Testing Equipment. The DCP tests were completed in accordance with ASTM International (ASTM) D6951 by driving a 5/8-in.- diameter steel rod with a cone tip into the soil using a 17.6-lb sliding hammer dropped a fixed height of 22.6 in. The number of blows required to drive the probe approximately 5 cm (2 in.) was recorded to depths ranging from 918 to 936 mm (3 to 3.1 ft). The DCP blow counts were used to estimate a California bearing ratio(CBR)value for the in-situ subgrade. Infiltration Testing On December 14, 2018, falling head infiltration tests were conducted in two boreholes, designated I-1 and 1-2, at a depth of about 3 ft below existing site grades. The borehole was blind-drilled to the test depth using a 4-in.-diameter hand auger provided and operated by GRI. The approximate locations of the infiltration tests are shown on Figure 2. The unfactored, field-measured infiltration rates recorded at a specific depth within a specific soil unit are tabulated below. Depth of Average Infiltration Boring Infiltration Test,ft Rate, in./hour Soil Classification I-i 3 0Clayey SILT to Silty CLAY (Residual Soil) 1-2 3 p Clayey SILT to Silty CLAY (Residual Soil) The falling head infiltration tests were completed in general conformance with the City of Portland 2016 Stormwater Management Manual (SMM), using the encased falling head method outlined in Section 2.3.6 of the manual. The infiltration tests were completed inside a PVC pipe, which was embedded a couple of inches below the drilled depth and filled with water to a height of approximately 1 ft above the drilled depth. After soaking, infiltration testing was conducted by re-establishing the water level in the pipe to the target height and recording the drop in water level over 1 hour or until the water completely drained, whichever occurred first. Where necessary, the infiltration test was repeated until consecutive tests showed little or no change in infiltration rate. LABORATORY TESTING General The samples obtained from the borings were examined in our laboratory, where the physical characteristics of the samples were noted and the field classifications modified where necessary. At the time of classification, the natural moisture content of each sample was determined. Additional testing included Torvane shear strength, dry unit weight measurements, Atterberg limits determinations, one- dimensional consolidation tests,and grain-size analyses. A summary of the laboratory test results is provided in Table 3A. The following sections describe the testing program in more detail. CI A-2 Natural Moisture Content Natural moisture content determinations were made in conformance with ASTM D2216. The results are summarized on Figures 1A through 11A and in Table 3A. Torvane Shear Strength The approximate undrained shear strength of fine-grained soils was determined using a Torvane shear device. The Torvane is a hand-held apparatus with vanes that are inserted into the soil. The torque required to fail the soil in shear around the vanes is measured using a calibrated spring. The results of the Torvane shear strength tests are summarized on Figures 4A and 10A Undisturbed Unit Weight The unit weight, or density, of undisturbed soil samples was determined in the laboratory in conformance with ASTM D2937. The results are summarized on Figures 4A and 10A and in Table 3A. Atterberg Limits Atterberg limits testing was performed on two samples of residual soil in conformance with ASTM D4318. The test results are summarized on the Plasticity Chart, Figure 12A, Figures 5A and 6A, and in Table 3A. One-Dimensional Consolidation One- dimensional consolidation tests were performed in conformance with ASTM D2435 on relatively undisturbed soil samples extruded from Shelby tubes. This test provides data on the compressibility of underlying fine-grained soils, necessary for settlement studies. The test results are summarized on Figures 13A and 14A in the form of a curve showing percent strain versus applied effective stress. The initial dry unit weight and moisture content of the sample are also shown on the figures. Grain-Size Analysis Washed-Sieve Method. To assist in classification of the soils, samples of known dry weight were washed over a No. 200 sieve. The material retained on the sieve was oven-dried and weighed. The percentage of material passing the No. 200 sieve was then calculated. The results are summarized on Figures 2A, 3A, 4A, and 10A, and in Table 3A. G gigA-3 Table 'IA GUIDELINES FOR CLASSIFICATION OF SOIL Description of Relative Density for Granular Soil Standard Penetration Resistance Relative Density (N-values),blows per ft very loose 0-4 loose 4- 10 medium dense 10-30 dense 30-50 very dense over 50 Description of Consistency for Fine-Grained(Cohesive)Soils Standard Penetration Torvane or Resistance(N-values), Undrained Shear Consistency blows per ft Strength,tsf very soft 0-2 less than 0.125 soft 2-4 0.125-0.25 medium stiff 4-8 0.25-0.50 stiff 8- 15 0.50- 1.0 very stiff 15-30 1.0-2.0 hard over 30 over 2.0 Grain-Size Classification Modifier for Subclassification Boulders: Primary Constituent Primary Constituent >12 in. SAND or GRAVEL SILT or CLAY Cobbles: Adjective Percentage of Other Material (by weight) 3 12 in. trace: 5- 15 (sand, gravel) 5- 15 (sand, gravel) Gravel: some: 15-30 (sand,gravel) 15-30(sand, gravel) 3/4-3/4 in. (fine) sandy, gravelly: 30-50(sand, gravel) 30-50(sand, gravel) /4-3 in. (coarse) Sand: No. 200 No.40 sieve(fine) trace: <5 (silt,clay) Relationship of clay and No.40- No. 10 sieve(medium) some: 5 12 (silt clay) silt determined by No. 10-No.4 sieve(coarse) silty, clayey: 12-50(silt, clay) plasticity index test Silt/Clay: pass No. 200 sieve GRU Table 2A GUIDELINES FOR CLASSIFICATION OF ROCK Relative Rock Weathering Scale Term Field Identification Fresh Crystals are bright. Discontinuities may show some minor surface staining. No discoloration in rock fabric. Slightly Rock mass is generally fresh. Discontinuities are stained and may contain clay. Some discoloration in rock Weathered fabric. Decomposition extends up to 1 in. into rock. Moderately Rock mass is decomposed 50%or less. Significant portions of rock show discoloration and weathering Weathered effects. Crystals are dull and show visible chemical alteration. Discontinuities are stained and may contain secondary mineral deposits. Predominantly Rock mass is more than 50%decomposed. Rock can be excavated with geologist's pick. All Decomposed discontinuities exhibit secondary mineralization. Complete discoloration of rock fabric. Surface of core is friable and usually pitted due to washing out of highly altered minerals by drilling water. Decomposed Rock mass is completely decomposed. Original rock"fabric"may be evident. May be reduced to soil with hand pressure. Relative Rock Hardness Scale Hardness Approximate Unconfined Term Designation Field Identification Compressive Strength Extremely RO Can be indented with difficulty by thumbnail. May be < 100 psi Soft moldable or friable with finger pressure. Very R1 Crumbles under firm blows with point of a geology pick. 100-1,000 psi Soft Can be peeled by a pocket knife and scratched with fingernail. Soft R2 Can be peeled by a pocket knife with difficulty. Cannot be 1,000 4,000 psi scratched with fingernail. Shallow indentation made by firm blow of geology pick. Medium R3 Can be scratched by knife or pick. Specimen can be 4,000-8,000 psi Hard fractured with a single firm blow of hammer/geology pick. Hard R4 Can be scratched with knife or pick only with difficulty. 8,000-16,000 psi Several hard hammer blows required to fracture specimen. Very R5 Cannot be scratched by knife or sharp pick. Specimen > 16,000 psi Hard requires many blows of hammer to fracture or chip. Hammer rebounds after impact. RQD and Rock Quality Relation of RQD and Rock Quality Terminology for Planar Surface RQD(Rock Description of Bedding Joints and Fractures Spacing Quality Designation),% Rock Quality Laminated Very Close < 2 in. 0-25 Very Poor Thin Close 2 in.—12 in. 25-50 Poor Medium Moderately Close 12 in.—36 in. 50-75 Fair Thick Wide 36 in.—10 ft 75-90 Good Massive Very Wide > 10 ft 90-100 Excel lent GR D -- Table 3A SUMMARY OF LABORATORY RESULTS Sample Information Atterberg Limits Moisture Dry Unit Liquid Plasticity Fines Location Sample Depth,ft Elevation,ft Content, % Weight,pcf Limit, % Index, % Content,% Soil Type B-1 S-1 1.0 -- 25 - - - - Silty CLAY S-2 2.5 - 29 -- - -- - Silty CLAY S-3 5.0 - 26 -- - -- - Silty CLAY B-2 S-1 1.0 -- 25 - - - - Silty CLAY S-2 2.5 - 23 -- - - 86 Silty CLAY S-3 5.0 - 26 -- - -- - Silty CLAY B-3 S-1 2.5 -- 26 - - - 88 Silty CLAY S-2 5.0 - 28 -- - - - Silty CLAY S-3 7.5 - 29 -- - -- 94 Silty CLAY S-3 8.3 - 27 -- - -- 45 Silty SAND S-4 10.0 - 44 -- - -- - Silty SAND B-4 S-1 3.0 -- 21 - - - 92 Silty CLAY S-1 3.5 - 19 101 - - - Silty CLAY S-2 4.5 - 25 - - - - Silty CLAY S-3 7.5 - 39 -- - -- 39 Silty SAND S-4 10.0 - 37 -- - -- - Silty SAND S-5 12.5 - 26 -- - - - Silty SAND B-5 S-1 1.0 -- 27 - - - - Silty CLAY S-2 2.5 - 20 -- 52 29 - Silty CLAY S-3 5.0 - 18 - - - - Silty CLAY B-6 S-2 5.0 -- 30 - 46 18 -- Silty CLAY S-3 7.5 - 37 -- - -- 40 Silty SAND S-4 10.0 - 33 - - -- - BASALT B-7 S-1 1.0 -- 26 - - - - Silty CLAY S-2 2.5 - 26 - - -- - Silty CLAY S-3 5.0 - 25 - - -- - Silty CLAY B-8 S-1 1.0 -- 24 - - - - Silty CLAY S-2 2.5 - 22 -- - -- - Silty CLAY S-3 5.0 - 26 -- - -- - Silty CLAY B-9 S-1 2.5 -- 28 - - - - Silty CLAY S-2 5.0 - 27 - - - - Silty CLAY S-3 7.5 - 40 -- - -- - Silty CLAY B-10 S-1 3.0 - 25 89 -- - - Silty CLAY S-1 4.2 - 22 -- - -- 93 Silty CLAY S-2 4.5 - 28 -- - - - Silty CLAY S-4 10.0 - 54 -- - - 65 BASALT B-11 S-1 1.0 - 27 -- - -- - Silty CLAY S-2 2.5 - 20 - - -- - Silty CLAY S-3 5.0 - 29 -- - -- - Silty CLAY TIIPage 1 of 1 BORING AND TEST PIT LOG LEGEND SOIL SYMBOLS SAMPLER SYMBOLS Symbol Typical Description Symbol Sampler Description •�{• LANDSCAPE MATERIALS 1 2.0-in. O.D. split-spoon sampler and Standard %.::a+ 1 Penetration Test with recovery (ASTM D1586) FILL oss:. Shelby tube sampler with recovery "� ' (ASTM D1587) o"l 3.0-in. O.D. split-spoon sampler with recovery o c° GRAVEL; clean to some silt, clay,and sand (ASTM D3550) o d:i, o.CSe Sandy GRAVEL; clean to some silt and clay Grab Sample o ✓I l Qa Silty GRAVEL; up to some clay and sand Ill Rock core sample interval o`_) 4 Clayey GRAVEL; up to some silt and sand Sonic core sample interval SAND; clean to some silt, clay, and gravel Geoprobe sample interval CM: i..!;g4 Gravelly SAND; clean to some silt and clay INSTALLATION SYMBOLS .•,.<•,..' Silty SAND; up to some clay and gravel Symbol Symbol Description '!? Clayey SAND; up to some silt and gravel Flush-mount monument set in concrete Z SILT; up to some clay, sand, and gravel Concrete,well casing shown where applicable 111.1 Gravelly SILT; up to some clay and sand j'j Benapp o it eseal, well casing shown where Sandy SILT; up to some clay and gravel Filter pack, machine slotted well casing shown — • where applicable Clayey SILT; up to some sand and gravel Grout,vibrating-wire transducer cable shown ' _ where applicable f/7 CLAY; up to some silt, sand, and gravel ® Vibrating-wire pressure transducer 1 Gravelly CLAY; up to some silt and sand I 1-in.-diameter solid PVC qSandy CLAY; up to some silt and gravel 1-in.-diameter hand slotted PVC "/'/ Silty CLAY; up to some sand and gravel Grout, inclinometer casing shown where applicable v PEAT FIELD MEASUREMENTS BEDROCK SYMBOLS Symbol Typical Description Symbol Typical Description Q Groundwater level during drilling and date r - measured +++ BASALT 1 Groundwater level after drilling and date o +++ - measured MUDSTONE Rock core recovery (%) a W =� SILTSTONE Rock quality designation (RQD, %) o SANDSTONE R cp SURFACE MATERIAL SYMBOLS Symbol Typical Description 8 0 ■ Asphalt concrete PAVEMENT co 1- Portland cement concrete PAVEMENT 0 a ov l 0 aCy Crushed rock BASE COURSE Er- 0 m o CLASSIFICATION OF MATERIAL o a • BLOWS PER FOOT 1— I-- o • MOISTURE CONTENT, U_ 0 LL Z Lu o 0 FINES CONTENT, _ = J J " LIQUID LIMIT,% COMMENTS AND w w - Q ¢ o �-PLASTIC LIMIT,% ADDITIONAL TESTS o o Surface Elevation: Not Available o - w c' m 0 50 100 II Silty CLAY to clayey SILT,trace fine-grained sand, 1 brown,medium stiff,contains organics,4-in.-thick 2 7 J heavily rooted zone at ground surface(Residual s-1 3 Son) 4 ` I ---stiff at 2.5 ft S-2 -1 LI lo / 5 j ---very stiff below 5 ft 1 6 16 ,L /11 S 3 0 • (12/14/2018) 6.5 Groundwater not encountered 10- i 15- 20- 25— _ a — I-- . 0 0 — Ili I- a — J a w 30— 1— a 0 a > — w J W — 0 z U) 35— , a. 0 o — J 0 z — O m — . 0—40 0 0.5 1.0 • Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. TORVANE SHEAR STRENGTH,TSF Date Started: 12/14/18 GPS Coordinates: Not Available ■ UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Hollow-Stem Auger Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight:140 lb ft 0 BORING B—1 1 Hole Diameter: 8 in. Drop:30 in. Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.1A CLASSIFICATION OF MATERIAL o a ♦ BLOWS PER FOOT Z % J p • MOISTURE CONTENT, v u~ g w Lu o 0 FINES CONTENT,% J a. J ° �E LIQUID LIMIT,% COMMENTS AND a ¢ a ~ 2 2 O PLASTIC LIMIT, o Surface Elevation: Not Available z `�" `��' ° 0 50 100 ADDITIONAL TESTS jySilty CLAY to clayey SILT,trace fine-grained sand, brown,medium stiff,contains organics,4-in:thick 2 5 heavily rooted zone at ground surface(Residual s-1 2 ( Soil) 3 --stiff below 2.5 ft S-2 s 1 8 1 _ 5 5..3 4 121 /1 1 17 (12/14/2018) 8.5 Groundwater not encountered 10- 15- 20- 25— a - _ -- O H — J a w 30— w 0 0 w W — _ 0 z 35— Cl 0 ( 0 c-—40 0 0.5 1.0 • Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. TORVANE SHEAR STRENGTH,TSF Date Started: 12/14/18 GPS Coordinates: Not Available ■ UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Hollow-Stem Auger Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight:140 lb G BORING B-2 Hole Diameter: 8 in. Drop:30 in. Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.2A BLOWS PER FOOT o CLASSIFICATION OF MATERIAL o a z • MOISTURE CONTENT, u_ o L g ? Lu o ❑ FINES CONTENT,% LIQUID LIMIT,% COMMENTS AND a a d rip a ¢ 0 PLASTIC LIMIT,% ADDITIONAL TESTS o Surface Elevation: Not Available o Z `.o Cl) co 0 50 100 Silty CLAY to clayey SILT,trace fine-grained sand, brown,stiff,contains organics,4-in.-thick heavily {- rooted zone at ground surface(Residual Soil) 6 _14 S-1 8 * '' Loss of drilling Fluid y 6 I t _ circulation between depths of 2.5 to 7.5 ft. 5 1 Drilling mud observed 6 ._12 I seeping out of the_,S-2 5 ,_* slope approximately 7t—__ 10 ft downhill from � I exploration 4 , t Silty SAND,green gray with rust staining and white 24 ;r;-;••• mineralization,dense,relict rock structure,fine to 10 : coarse grained,contains gravel-sized fragments of s as _-..-- _.7.:;r:. predominantly decomposed basalt(Decomposed s-4 I 18 r: Basalt) r: .;1:: :: 12.5 40 50-5015 +++ S-5 50 "", —•+•++ BASALT,gray,brown,and green gray with rust +++ staining,predominantly decomposed to 50/5 decomposed,extremely soft to very soft(RO to R1) 1"15— '(Columbia River Basalt) (12/13/2018) 20— 25— — . n H - II O q — uJ 1-- a — w 30— H . _ I a — I a 0 E C > — w J i w I z 35— . ' . 0 — O . . - o — J 0 z — -- Q CO — CD—40 I 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. ♦ TORVANE SHEAR STRENGTH,TSF Date Started: 12/13/18 GPS Coordinates: Not Available ■ UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Mud Rotary Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight:140 lb G R Q BORING B-3 Hole Diameter: 4 in. Drop:30 in. Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.3A BLOWS PER FOOT o o CLASSIFICATION OF MATERIAL a z 1- -I I- I- o • MOISTURE CONTENT,% 0 L w Lu o 0 FINES CONTENT,% _ _ = J _1 J ° r�LIQUID LIMIT,% COMMENTS AND w w z a < o PLASTIC LIMIT,% ADDITIONAL TESTS o co Surface Elevation: Not Available o _ a, up m 0 50 100 yi 1 Silty CLAY to clayey SILT,trace fine-grained sand, 1 I brown,stiff,contains organics,4-in.-thick heavily rooted zone at ground surface(Residual Soil) 1 S 1 9 0.60 ❑' l I Dry Density=101 pcf I ---very stiff below 4.5ft _17�. . 5 • S-2 7 i 10 \ - +.,:•.'^Silty SAND,gray with rust staining,medium dense, 7.5 7 21-i ii t::;: relict rock structure,fine to coarse grained S-3 is I :a ". (Decomposed Basalt) 10-:4 :;: ---contains gravel-sized fragments of predominantly 17 54 f:`;r! decomposed basalt,very dense below 9.5 ft sa 27 • A a. ---white and green mineralization below 12.5 ft 26 J/ - 74 ` '••::: S-5 36 • :r ri 38 r:r.'i:: al\-, 15+1K— 15.0 gp 32-50/4.5"- +++ BASALT,gray with rust staining and green to white S-6 1- 32 " A - mineralization,predominantly decomposed to 15.9 _ decomposed,extremely soft to very soft(RO to R1) (Columbia River Basalt) - (12/13/2018) - . 20- 25- m _ ,7,-- 1- 0 o - I 1- a - a w 30- H a H a 0 5_ - 0 > - . w J - w _ 0 z 35- I o - 0 o - z z - E T o on - E 0-40 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. • TORVANE SHEAR STRENGTH,TSF Date Started: 12/13/18 GPS Coordinates: Not Available ■ UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Mud Rotary Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight:140 lb RT BORING B"t/�Hole Diameter: 4 in. Drop:30 in. 1Note:See Legend for Explanation of Symbols Energy Ratio: 1 APR.2019 JOB NO.5970-K FIG.4A c9 CLASSIFICATION OF MATERIAL Z w A BLOWS PER FOOT of O • MOISTURE CONTENT,% 'i v ~ Z ~ o 0 FINES CONTENT,% w w `� COMMENTS AND 1— a F ¢ a_ a �—LIQUID LIMIT, w eL w Z Q Q of PLASTIC LIMIT,% ADDITIONAL TESTS o 0 Surface Elevation: Not Available o _ cn m 0 50 100 Silty CLAY to clayey SILT,trace fine-grained sand, brown,soft to medium stiff,contains organics, 1 I t 4 ' 4-in.-thick heavily rooted zone at ground surface s-1 1 (Residual Soil) 3 ,_ .,_ / ! medium stiff to stiff at 2.5 ft S-2 4 a �- J T 5/ ---very stiff below 5 ft a1s1_ I S-3 7 - { — (12/14/2018) 6.5 s T Groundwater not encountered 10- 15— , 20— _. 25— . 0, _ N- a — F 0 0 — ui . F a — . J a F 30— I . a — F a 0 o 0 . > — W -J W — 0 Z U) 35— a 0 — 0 o — (0 . . z — ce 0] — "—40 0 0.5 1.0 • Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. TORVANE SHEAR STRENGTH,TSF Date Started: 12/14/18 GPS Coordinates: Not Available • UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Hollow-Stem Auger Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight:140 lb G RO BORING B-5 Hole Diameter: 8 in. Drop:30 in. Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.5A co z ,, A BLOWS PER FOOT o CLASSIFICATION OF MATERIAL o a I- ,_ o • MOISTURE CONTENT, L.L. v g w uj 0v 0 FINES CONTENT,% a ? a a a ��LIQUID LIMIT,% COMMENTS AND w 2 „a, z a s o PLASTIC LIMIT,% ADDITIONAL TESTS o c0 Surface Elevation: Not Available o — `o `) Co 0 50 100 i Silty CLAY to clayey SILT,trace fine-grained sand, brown mottled gray,stiff,contains organics, 4-in:thick heavily rooted zone at ground surface (Residual Soil) I — S-1 • 5 / 5 1 S-2 6 ♦ •I .`' Silty SAND,gray with rust staining and white 7 5 13 I 43 S-3 I 14 i••-r••• mineralization,dense,relict rock structure,fine to ::•:: coarse grained,contains gravel-sized fragments of I17 / 10 +4- predominantly decomposed basalt(Decomposed , io.o 25-16-a 25 / .____ —+++ , ) S-4 16 + J OIS° +++ BASALT,gray with rust staining and white 50/5^ —+++ mineralization,predominantly decomposed to - —+++ decomposed,extremely soft to very soft(RO to R1) — ' _ _ - +++ (Columbia River Basalt) -- —+++ --some vesicles,moderately weathered to , 15—+++ predominantly decomposed,very soft to medium Run 1 ender�� hard(R1 to R3),open joints with clay infilling below —+++ 12ft +++ _ I _ _+++ +++ //� +++ +++ 20 +++ Run 2 +++ •//�� d , —+++ . . - +++ 1 — (12/14/2018) 22.5 — 25— . n_ v — H . 0 0 — w F- a — J a w 30— 1- . a 1 a 0 Er- C9 — ,> w J W — 0 z in 35— a 0 0 J — E . IllUill I 40 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. ♦ TORVANE SHEAR STRENGTH,TSF ■ UNDRAINED SHEAR STRENGTH,TSF Date Started: 12/14/18 GPS Coordinates: Not Available Drilling Method: Mud Rotary Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight:140 lb RI BORING B'6 Hole Diameter: 4 in. Drop:30 in. Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG 6A A BLOWS PER FOOT o CLASSIFICATION OF MATERIAL _o • a z • MOISTURE CONTENT,% F- 0 I- ~ o I o 0 FINES CONTENT,% __ w " COMMENTS AND _ _ ,a J J r--{ LIQUID LIMIT, o od o_ 2 2 oLL/ PLASTIC LIMIT,% ADDITIONAL TESTS Surface Elevation: Not Available o (n co 0 50 100 ySilty CLAY to clayey SILT,trace fine-to medium-grained sand,brown,very soft to soft, 0 2 contains organics,4-in.-thick heavily rooted zone at s-i I yground surface(Residual Soil) 1 I ;/ ---medium stiff at 2.5 ft s-2 1 /\\_[ t 5 t 5 i --stiff to very stiff below 5 ft s 11---11 , _ � I ! S_3 60 - (12/14/2018) 6.5 Groundwater not encountered 10— t 15— 20— 25— 0) — n v — F- 0 0 - ui F- a - J a w 30— F- a F- a 0 5: — C > — . w J W 0 z - 35— . a 0 — 0 0 — 0 z z 0 E C-40 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. • TORVANE SHEAR STRENGTH,TSF Date Started: 12/14/18 GPS Coordinates: Not Available ■ UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Hollow-Stem Auger Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight:140 lb I Rii BORING B- 7 Hole Diameter: 8 in. Drop:30 in. Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.7A _ w o CLASSIFICATION OF MATERIAL Z w I— A BLOWS PER FOOT u v 1— o O CL • MOISTURE CONTENT, _ _ w w w ov FINES CONTENT,% COMMENTS AND H. a F- < a a '---{—LIQUID LIMIT, o Surface Elevation: Not Available o - < < m PLASTIC LIMIT,% ADDITIONAL TESTS y� 0 50 100 1/ Silty CLAY to clayey SILT,trace fine-grained sand, brown,stiff to very stiff,contains organics, 2 to J4-in.-thick heavily rooted zone at ground surface s-1 3 (Residual Soil) 7 �� 5 1RdS-2 8 / 10 5 t ill — ;�; S-3 I7 •51 6 . 86.5 Sample saude— (12/14/2018) decomposed blt at — tip of sampler Groundwater not encountered - hi 10— 15- 20- 25— m n v - H 0 ui H a - J a w 30— F a _ a 0 C > - w J w 0 Z 35— Li- -0 o — J 0 Z — ec a: — c9-40 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. • TORVANE SHEAR STRENGTH,TSF Date Started: 12/14/18 GPS Coordinates: Not Available • UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Hollow-Stem Auger Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight: lb 30 Hole Diameter: 8 in. Drop:30 in. Ij BORING B-8 Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.8A (.5 CLASSIFICATION OF MATERIAL z W I— • BLOWS PER FOOT FLL.— F o o CL z • MOISTURE CONTENT,% i = " w w vo ❑ FINES CONTENT,% a a F - a a ° I---(—LIQUID LIMIT,% COMMENTS AND o co Surface Elevation: Not Available o z °a °a 0 PLASTIC LIMIT,% ADDITIONAL TESTS I/ 0 50 100 Silty CLAY to clayey SILT,trace fine-grained sand, // brown mottled gray,stiff,contains organics, �/ 4-in.-thick heavily rooted zone at ground surface _// (Residual Soil) 3 13 J l S-1 7 ril) 5 6 _ I a 11 I 2 S-2 1 5 4 • 6 .., S-3 1 7 +++ BASALT,gray with rust staining and white 8 5 13 10—+++ mineralization,predominantly decomposed to +++ decomposed,extremely soft to very soft(RO to R1) 23 23-50/5^- —+++ \(Columbia River Basalt) r 109 s-a 15015" — • _ (12/13/2018) 15- 20- 25— — — 0 — o W F- a a 2 30— w ~ _ a 0 n o + III > — w J w — 0 z Co 35— a 0 - c0 0 - J 0 Z - 0 0 E °-40 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. TORVANE SHEAR STRENGTH,TSF Date Started: 12/13/18 GPS Coordinates: Not Available • UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Mud Rotary Hammer Type:Auto Hammer RO Equameter: CME 850 Track-Mounted Drill Rig Weight:140 i Ib (�Hole Diameter: 4 in. Drop:30 in BORING B-9 Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.9A CLASSIFICATION OF MATERIAL z W ,- • BLOWS PER FOOT 1- o F o o f z • MOISTURE CONTENT,% `� `� Z 0 ❑ FINES CONTENT,% a a F a s +..--L LIQUID LIMIT,% COMMENTS AND o Surface Elevation: Not Available o z < < 0 PLASTIC LIMIT,% ADDITIONAL TESTS m 0 50 100 Silty CLAY to clayey SILT,trace fine-grained sand, I brown,very stiff,contains organics,4-in:thick heavily rooted zone at ground surface(Residual Soil) 0.50 6-1 * '•♦ Dry Density=89 pcf I 5 6 18 �4 L S-2 7 I 11 -+++ BASALT,brown with rust staining,predominantly 7.5 10 a -+++ decomposed to decomposed,extremely soft to very s 3 I 15 +++ soft(RO to R1)(Columbia River Basalt) 10+++ ---extremely soft to very soft(RO to R2)below 10 ft Ill _14 _+++ S-4 7 _ 0 0 +++ 7 +++ —+++ +++ Ni +++ 15 '48 +++ S-5 I 17 —+++ 31 15—+++ +++ 18 —+++ / S-6I 17 3 A +++ 18 +++ +++ ++ +++ _+++ +++ 20 +++ --gray with green mineralization below 20 ft '�S-6 I38 32 38-32-5D15""A +++ — (12/13/2018) 21.4 50/5^ 25— N. a - I 0 O - w F- a - -I a w 30— a — F- a 0 K 0 > — w J w O z E 35— a 0 - 0 0 - 0 z - 2 0 co - K cD—40 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. • TORVANE SHEAR STRENGTH,TSF Date Started: 12/13/18 GPS Coordinates: Not Available • UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Mud Rotary Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight: lb BORING B- O 30 G RO Hole Diameter: 4 in. Drop:30 in. Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.10A o CLASSIFICATION OF MATERIAL z w ,- A BLOWS PER FOOT o F- o • MOISTURE CONTENT,%= " < w w ov FINES CONTENT,% ¢ a ii r--( LIQUID LIMIT,% COMMENTS AND W - a a o PLASTIC LIMIT,% ADDITIONAL TESTS o c0 Surface Elevation: Not Available to, z co co m 0 50 100 Silty CLAY to clayey SILT,trace fine-grained sand, 1 I brown,very soft to soft,contains organics, 4-in.-thick heavily rooted zone at ground surface s-1 0 2 I (Residual Soil) 2 \ y ---stiff below 2.5 ft S-2 4 —13 6 7 5 I I 3 101 S-3 4 (12/14/2018) 6.5 6 Groundwater not encountered 10— — 15- 20- 25— m - H ° - ui F- a — a w 30— F- a 0 ° w _ 0 z 35— a C� - ° o — ° O m - K • °—40 0 0.5 1.0 Logged By: M.Rauthause Drilled by: Western States Soil Conservation,Inc. • TORVANE SHEAR STRENGTH,TSF Date Started: 12/14/18 GPS Coordinates: Not Available ■ UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Hollow-Stem Auger Hammer Type:Auto Hammer Equipment: CME 850 Track-Mounted Drill Rig Weight: lb G f Q BORING B-11 Hole Diameter: 8 in. Drop:30in. 30 Note:See Legend for Explanation of Symbols Energy Ratio: APR.2019 JOB NO.5970-K FIG.11A o CLASSIFICATION OF MATERIAL z w F • BLOWS PER FOOT 1— J o o z • MOISTURE CONTENT,70 _ " n w w ov 0 FINES CONTENT,% �— ° F ii a r---( LIQUID LIMIT,% COMMENTS AND w 2 2 o PLASTIC LIMIT,% ADDITIONAL TESTS o 0 Surface Elevation: Not Available o F. m 0 50 100 � ' Silty CLAY to clayey SILT,trace fine-grained sand, J brown,stiff,contains organics,4-in.-thick heavily rooted zone at ground surface(Residual Soil) 2 10 S-1 1 4 • ji),/ 6 5 3 _11 S-2 r 5 Il 6 3 12 l S3 5 7 10 i ,/ 4 15 <4:, I._ 11.0 S-4 j 7 _ �:t:•j.� Silty SAND,gray with pink,white,and red 1 8 4 t . mineralization,medium dense,relict rock structure, —+�++�fine grained(Decomposed Basalt) / 12.5 11 16 ' +++ BASALT,gray with rust staining and pink to white s 5 1 s A +++ mineralization,predominantly decomposed to 15-4+++ decomposed,extremely soft to soft(RO to R2), _+++ open joints with clay infilling(Columbia River S-6 I 10 17 +++ Basalt) 7 '4\ .' , +++ —+++ 20—+++ 10 —+++ S-7 17 3 +++ 16 _+++ +++ 30 30-5/4"- 25—+++ ---some vesicles,moderately weathered to slightly S-8 - 5/4• _+++ weathered,soft to hard(R2 to R4),closed fractures / - +++ below 25 ft a +++ C_1 +++ W 30 (4/4/2019) 2s.o — a F — o L) > — w J w — 0 z 35— a 0 — 0 o — J 0 z E 0 co - E -40 0 0.5 1.0 Logged By: G.Martin Drilled by: Western States Soil Conservation,Inc. • TORVANE SHEAR STRENGTH,TSF Date Started: 4/4/19 GPS Coordinates: 45.4074°N -122.8456°W(WGS 84) II UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Mud Rotary Hammer Type:Auto Hammer Equipment: CME 55 HT Track-Mounted Drill Rig Weight:140 lb /- 1 BORING B- 1Hole Diameter. 5 in. Drop:3030 in. (�J� RO1 2 Note:See Legend for Explanation of Symbols Energy Ratio:0.76 APR.2019 JOB NO.5970-K FIG.12A a CLASSIFICATION OF MATERIAL z w 1— A BLOWS PER FOOT 1- --I 1— 0 O • MOISTURE CONTENT,% _ Li_ g w w Ov O FINES CONTENT,% COMMENTS AND a a = - a a r- 1-LIQUID LIMIT,% o Surface Elevation: Not Available o z < °¢ m PLASTIC LIMIT,% ADDITIONAL TESTS — 0 50 100 Silty CLAY to clayey SILT,trace fine-grained sand, I brown,medium stiff to stiff,contains organics, 4-in.-thick heavily rooted zone at ground surface (Residual Soil) 2 =8 S-1 q 4 A\ 5— ---very stiff at 5 ft 7 41 S-2 1 8 13 l 75 —:::i::;: Silty SAND,gray with pink,white,and red 11 40 --- - tr:•r.;� mineralization,medium dense,relict rock structure, S-3 22 }...,`•. fine grained(Decomposed Basalt) 18 ICI--;-:•: --very dense at 10 ft i a:°':nj 18 j 61 — +ci.•. S-4 27 — I - a; > 34 —+++ BASALT,gray with rust staining and pink to white 12.5 20 2a2s 50/5.5^ _+++ mineralization,predominantly decomposed to S-5 26 'A +++ decomposed,extremely soft to soft(RO to R2), 50/5.5° 15—+++ open joints with clay infilling(Columbia River _+++ Basalt) s-s 35 35 3S50/5' +++ 50/5" _,+++ +++ 24 _ +++ :;/i90 —+++ S-7 I 41 +++ qg 20—'+++ +++ +++ —+++ 24 47 +++ S-8 I 21 +++ 26 +++ 25—+++ +++ —+++ —some vesicles,moderately weathered to slightly 26 +++ weathered,soft to hard(R2 to R4),closed fractures S-9 50 26-sa5o/a" a —+++ below 26 ft o +++ 50/4" 7/7„ ,„ ,4 Ili I-- +t+ c-1 _A,44/11; ' (4/4/2019) 32.0 — / u, J CJ Z c 35— a - J U` -L - Fe m "-40 III 0 0.5 1.0 Logged By: G.Martin Drilled by: Western States Soil Conservation,Inc. • TORVANE SHEAR STRENGTH,TSF Date Started: 4/4/19 GPS Coordinates: 45.4075°N -122.8447°W(WGS 84) • UNDRAINED SHEAR STRENGTH,TSF Drilling Method: Mud Rotary Hammer Type:Auto Hammer Equipment: CME 55 HT Track-Mounted Drill Rig Weight:140 lb GHole Diameter: 5 in. Drop:30 in. RO BORING B-13 Note:See Legend for Explanation of Symbols Energy Ratio:0.76 APR.2019 JOB NO.5970-K FIG.13A .. .$. o CLASSIFICATION OF MATERIAL o a • MOISTURE CONTENT, U- 0 LL I- z I' 0 FINES CONTENT, ± a = I LIQUID LIMIT, I- PLASTIC LIMIT,% COMMENTS AND a ¢ a ADDITIONAL TESTS Surface Elevation: Not Available (,' °' 50 100 I Silty CLAY to clayey SILT,trace fine-grained sand,brown, _ �/ soft to medium stiff,contains organics,4-in.-thick heavily /� rooted zone at ground surface(Residual Soil) _/11y1 It 025 5—/ t ---ijy ill _ II 11111111111 10 +'++ - 10.0 +++ BASALT,gray and black,predominantly decomposed to 111111111111111111 —+++ decomposed,extremely soft to soft(RO to R2)(Columbia +-,-4- \River Basalt) ,-- 11.5 IIu■IuuIIII■uIulI.11 — (4/3/2019) IhllhIIiiIIIIIIIIIII Groundwater not encountered 15- 20— a a a w - 1n■1■11 •iuuuuisu a 25— uJ w F - H a o a > — w J W 0 — z a 30 00 0.5 1.0 o • TORVANE SHEAR STRENGTH,TSF a ~ Logged By: M.Rauthause Excavated by: Benchmark Contracting Equipment: CAT 326F Excavator 0 Date Started: 4/3/19 GPS Coordinates: Not Available I Note: See Legend for Explanation of Symbols G R I TEST PIT TP-13 APR.2019 JOB NO.5970-K FIG.14A o CLASSIFICATION OF MATERIAL o O a • MOISTURE CONTENT, `- I— z c- ❑ FINES CONTENT,% a = o_ J !--{ LIQUID LIMIT,% COMMENTS AND I__. g PLASTIC LIMIT, Surface Elevation: Not Available o () ADDITIONAL TESTS 0 50 100 -q Silty CLAY to clayey SILT,trace fine-grained sand,brown, II soft to medium stiff,contains organics,scattered _/ subrounded gravel and boulders,4-in.-thick heavily rooted zone at ground surface(Residual Soil) 0.25 � / 5f1 - ' 111 1111 111111Silty graystaining 6.5 1111111 1111111111 _..;s,: SAND, with rust and white . .::: mineralization,fine to coarse grained,contains gravel-to 111 11 111111.1111 11 1 11 —..'13 f boulder-sized fragments of predominantlydecomposed 0•i.ui 111 111= :} •• basalt(Decomposed Basalt) 10—;r:L,;F. ::.ice•• +++ BASALT,gray and black,predominantly decomposed to 11.0 +++ decomposed,very soft to soft(R1 to R2)(Columbia River +++ Basalt) —+++ +++ 1111111111111111111 �+++ ---moderately weathered to decomposed below 14 ft 1■111■11■11111■■1■1 +++ +++ 15 I++ 1111111011111 +++ +++ +++ --includes fragments of soft to medium hard(R2 to R3) +++ basalt at 16 ft 1111111111111111111 +++ —+++ ---includes fragments of medium hard(R3)basalt at 18 ft 111101011110 _ (4/3/2019) 18.5 20— Groundwater not encountered m n 1111111111111101 a F 0 0 - W F a 25— 2 w 1 a F- LU - 0 > - w -J W O - Z a 30 c? 0 0.5 1.0 0 ° • TORVANE SHEAR STRENGTH,TSF a ~ Logged By: M.Rauthause Excavated by: Benchmark Contracting g Equipment: CAT 326E Excavator O Date Started: 4/3/19 GPS Coordinates: Not Available I Note: See Legend for Explanation of Symbols GREI TEST PIT TP-15 APR.2019 JOB NO.5970-K FIG.16A - ..or.ae,.anrae,cna suusi.Hlfi .ufaNYk}N[i1Nl3l1rUftJi#!y(Vil/4raFlliti}jlbialvJW.w:ri.a.ere exeaw» ..a+�,,w, ..r.,,<..e r:ase,tae friaalu i 0 CLASSIFICATION OF MATERIAL a • MOISTURE CONTENT,% J LL v ❑ FINES CONTENT,% a i `_J LIQUID LIMIT,% , r""� COMMENTS AND w w PLASTIC LIMIT,% ADDITIONAL TESTS o Surface Elevation: Not Available 0 �' �' 50 100 - Silty CLAY to clayey SILT,trace fine-grained sand,brown, I _ medium stiff,contains organics,4-in.-thick heavily rooted zone at ground surface(Residual Soil) — I JA ■IIIIII■IHIIIIII y _ RUIIIP , r 1■1. 11■ 5— i 1 III 11111111 11111111 _ 111111111111111 11111� II MINIM MI i ' ' ■IIIIIIIIIIIIIIIII1I4 11■1111 ■11110■I 10— $ 15 :'A.!.: :•z•. Silty SAND,gray with rust staining and whiteIIIIIIIIIIIIIIIIIIII 15.0 .,�.x• mineralization,fine to coarse grained,contains gravel-to � .•>/• boulder-sized fragments of predominantly decomposed ++1 basalt(Decomposed Basalt) J 17 0 IIIIIIIIIIIIIIIIIII ' ' ` BASALT,gray and black,predominantly decomposed to 17.5 (decomposed,extremely soft to soft(RO to R2)(Columbia River Basalt) (4/3/2019) 20— Groundwater not encountered IIIIIIIIIII IIIII IIiiiiiioiiiiiiioIIIII■IIOONION 0 w a 25— 2 W a H o j EE J W Z a 30 0 0.5 1.0 o • TORVANE SHEAR STRENGTH,TSF a ~ Logged By: M.Rauthause Excavated by: Benchmark Contracting Equipment: CAT 326F Excavator O Date Started: 4/3/19 GPS Coordinates: Not Available Note: See Legend for Explanation of Symbols RI1 TEST PIT TP-16 APR.2019 JOB NO.5970-K FIG.17A o CLASSIFICATION OF MATERIAL o O a 0 MOISTURE CONTENT, "- i— z c- U FINES CONTENT,% a = J '----E LIQUID LIMIT,% COMMENTS AND 1.0 12a 2 PLASTIC LIMIT, Surface Elevation: Not Available o cn ADDITIONAL TESTS 0 50 100 // Silty CLAY to clayey SILT,trace fine-grained sand,brown, medium stiff,contains organics,4-in.-thick heavily rooted I VIE�1 zone at ground surface(Residual Soil) 5-/ 4F030 _ , III . _ 1 10 . .. - I I II ;.1.T'.:Silty SAND,gray with rust staining and white 13.5 mineralization,fine to coarse grained,contains gravel-to 15++"+-1 boulder-sized fragments of predominantly decomposed / 15.0 \basalt(Decomposed Basalt) J 15.5 !IR ■ — BASALT,gray and black,predominantly decomposed to decomposed,very soft to soft(R1 to R2)(Columbia River II - Basalt) , (4/3/2019) — Groundwater not encountered 20- - '_IOW _ '_1111 r w i , a J 25— 2 W Q Q 130 0 0.5 1.0 ° • TORVANE SHEAR STRENGTH,TSF _, Q. ~ Logged By: M.Rauthause Excavated by: Benchmark Contracting Equipment: CAT 326F Excavator 0 Date Started: 4/3/19 GPS Coordinates: Not Available I Note: See Legend for Explanation of Symbols GREI TEST PIT TP-17 APR.2019 JOB NO.5970-K FIG.18A o CLASSIFICATION OF MATERIAL LLI o a • MOISTURE CONTENT, I- v , z ❑ FINES CONTENT, 1- a = LU W I --{ LIQUID LIMIT,% COMMENTS AND I— w Cl_ PLASTIC LIMIT, o a N N ADDITIONAL TESTS Surface Elevation: Not Available 0 50 100 Silty CLAY to clayey SILT,trace fine-grained sand,brown, 1 — —� medium stiff,contains organics,4-in:thick heavily rooted zone at ground surface(Residual Soil) —</ _ I IP o.3o III IIIIIII 5—_ �/ III III_ III /I ji/ jir,//, 1/ 1111111 I III 111iii III III IIIIIIII II ■■I ■III■■III IIII II t0—f I , ++1+/ 11.0 IlIllIlIllOhIlIll BASALT,gray and black,predominantly decomposed to 11.5 IIIIIII■I IIIIIIIII decomposed,extremely soft to medium hard(RO to R3) (Columbia River Basalt) (4/3/2019) Groundwater not encountered 15— 11111111111111111 — IIIIIIIIIIIIIIIIII 20 111111111111111111 — IIIIIIIII. IIIIIIII IIIIIIIII IIIIIIII — 111111111111111111 o IIII.. ■IIIIIII■ Ld 25- iiiiiiii11111110 2 w a a E 0 > - w J w O - Z Ea!)-: 30 c? 0 0.5 1.0 • TORVANE SHEAR STRENGTH,TSF a iET H Logged By: M.Rauthause Excavated by: Benchmark Contracting Equipment: CAT 326F Excavator O Date Started: 4/3/19 GPS Coordinates: Not Available I Note: See Legend for Explanation of Symbols GREI TEST PIT TP-18 APR.2019 JOB NO.5970-K FIG.19A irimerimmimmraimm GROUP UNIFIED SOIL CLASSIFICATION GROUP UNIFIED SOIL CLASSIFICATION SYMBOL FINE-GRAINED SOIL GROUPS SYMBOL FINE-GRAINED SOIL GROUPS ORGANIC SILTS AND ORGANIC SILTY ORGANIC CLAYS OF MEDIUM TO HIGH OL CLAYS OF LOW PLASTICITY OH PLASTICITY,ORGANIC SILTS INORGANIC CLAYEY SILTS TO VERY FINE ML SANDS OF SLIGHT PLASTICITY MH INORGANIC SILTS AND CLAYEY SILT INORGANIC CLAYS OF LOW TO MEDIUM CL PLASTICITY CH INORGANIC CLAYS OF HIGH PLASTICITY 60 50 CH 40 0 X W ~ 30 CL • 0 cn 20 MH or OH 10 CL-ML ML or OL o 0 10 20 30 40 50 60 70 80 90 100 LIQUID LIMIT, % Location Sample Depth,ft Classification LL PL PI MC, • B-5 S 2 2.5 Silty CLAY, trace fine-grained sand, brown, 52 23 29 20 contains organics (Residual Soil) m B-6 S-2 5.0 Clayey SILT, trace fine-grained sand, brown 46 28 18 30 0 mottled gray, contains organics (Residual Soil) w -J 2 w E2 O w 0 O. uJ w N GRLI U F LU PLASTICITY CHART W m w APR. 2019 JOB NO. 5970-K FIG. 20A 0 5 10 Z_ 15 iiIuuIi!_iiiiiiiiiiiiiiii 1111=10111111111111 _�� ■■■11111�■■■■1111_■11..1111l1■■■■1111 ■■■11111�■■■11111�■■■■111M■■■■1111 20 25 0.01 0.1 1 10 100 STRESS, TSF Initial Location Sample Depth,ft Classification 7d,pcf MC, % • B-4 S 1 3.0 Silty CLAY to clayey SILT, trace fine-grained sand, brown, 90 22 contains organics (Residual Soil) w 0 w 0 a a. a. In 9 G RQ 0 Z I- CONSOLIDATION TEST J Q Co Z APR. 2019 JOB NO. 5970-K FIG. 21A 0 5 10 0 15 20 25 0.01 0.1 1 10 100 STRESS,TSF Initial Location Sample Depth,ft Classification Yd,pcf MC, % W • B 10 S 1 4.2 Silty CLAY to clayey SILT, trace fine-grained sand, brown, 93 24 0_ contains organics (Residual Soil) W I w 0 a LU w a IN 9 G Ra 0 0 Z CONSOLIDATION TEST J Q Z APR. 2019 JOB NO. 5970-K FIG.22A 13-6 Run 1 12.5- 17.5ft 13-6 Run 2 17.5-22.511 �, f •'�aa r,,,, , sir::. ... ., • p 4 iPM3 # s' f� r'EY/atJAae. ;ca#id4 s�7zi'r _a 4 �6 F't" f aet�z a It 1233 <. • BORING B-6 1 6-12 g, ; ,,. •♦ it. f%iEd.4F'rfw3f^ypl�1�[n ...2 •{1✓rt;! , tti IIff 5 6 7 6 g 1 0 1 1 1 2 1 3 14 115 116 1 7 1,8 1 9 2❑ r e 2 2 3 2 4 • !3 0 r .d' 21 1114 a L6I 39 ,E ESE ,, _ 9 yU b Uv Et 9b tt Ob6E 6E LE 9E S£ b - , 5970-h B-13 . Run I ^' 28.0-32.0 II ,,. '-eesasr�m�uroauxn. acaaaczcxec;:t>rrxsr- -. srssexS-raia:tT•� BORING B-12 AND B-13 GRD ROCK CORE PHOTOGRAPHS APR.2019 JOB NO. 5970-K FIG. 23A tx££t r�ftt r ef'°ev3LT q ro r,t°d '* 0 ,:'VYI 'j -a Id fam h' a? ilJ" .r42 � tit - A x` 7tSt !i �Tl .it ff£ _*y Sf 11 f Al''3 ` fxk pR4 ':,' �Rfq ,Y T..4% ,£d .p, -Fi # d,fif tt J x+ �� £t � t �tx E $j G, 'i h .�, 1*.''-I f �S pe £J efvft 9�� x t ' � 41""P` a vy + '- ,.B '- /r d� i f ,,"x[ t f 7*ff Y £s f Tax 1 'y-, pMP t Test Pit TP-13 Test Pit TP-14 '' ' '''''''414:: r` , t pert, i ,°u l xt " a tfd 1i.1�,. Ir w2%- n,. £J� r� fr. 1, 6 i'x Af, 'f°'/ r.il 1141,4''440'P �} f t �" k !r 'fix t t •f�}{ �� a ,, �t,a '_. I 1 f 4 �,i e to/E 5t ' .,.e ., ..: w , rf ✓s TestTest Pit TP-16 Pit TP-15 G R 0 TEST PIT FIELD T APR.2019 JOBPHO NO. 5970 KOGRAPHS FIG.24A r f rj �s9f �.aJ ;. +r`- •"a" ` J r""P t +T.aw y F&., a +i aj, t 4� is ' L! ` 0t `4, a i';',;),,. i, g,, L, '^nay'" a2' ,x , '.. r} Y r.' r,Y ''',., f!,4 £':, 1 J 3 ksit f i}7 tdj ) f F a�5pa F :.iMd'•de'1' ram.'+ ,f TP-17 "'"` y TP-18 Test Pit TP-17 Test Pit TP-18 GRD TEST PIT FIELD PHOTOGRAPHS APR.2019 JOB NO. 5970-K FIG.25A APPENDIX B 2006 GeoDesign, Inc., Explorations KEY TO TEST PIT AND BORING LOG SYMBOLS SYMBOL SAMPLING DESCRIPTION I] Location of sample obtained in general accordance with ASTM D 1586 Standard Penetration Test with recovery Location of sample obtained using thin wall, Shelby tube, or Geoprobe® sampler in general accordance with ASTM D 1587 with recovery E Location of sample obtained using Dames & Moore sampler and 300-pound hammer or pushed with recovery 1 Location of sample obtained using Dames & Moore sampler and 140-pound hammer or pushed with recovery Graphic Log of Soil and Rock Types VILocation of grab sample :: � Observed contact : ;• •: between soil or rock units — '� (at depth indicated) Rock coring interval Inferred contact between soil or rock units Water level during drilling (at approximate depths , • ' - indicated) 1 Water level taken on date shown GEOTECHNICAL TESTING EXPLANATIONS PP Pocket Penetrometer DD Dry Density TOR Torvane ATT Atterberg Limits CON Consolidation CBR California Bearing Ratio DS Direct Shear OC Organic Content P200 Percent Passing U.S. Standard No. 200 P Pushed Sample Sieve RES Resilient Modulus HYD Hydrometer Gradation VS Vane Shear UC Unconfined Compressive Strength kPa kiloPascal SIEV Sieve Gradation a ENVIRONMENTAL TESTING EXPLANATIONS 0 b CA Sample Submitted for Chemical Analysis ND Not Detected r ov PID Photoionization Detector Headspace NS No Visible Sheen Analysis ppm Parts Per Million SS Slight Sheen ° P Pushed Sample MS Moderate Sheen HS Heavy Sheen 11'a� GEODESIGNz £ IS575SWSequoiaParkway-Suite ISO KEY TO TEST PIT AND BORING LOG SYMBOLS TABLE A-1 i° Portland OR 97224 Z ., Off 503.968.8787 Fax 503.968.3068 ,� SOIL CLASSIFICATION SYSTEM CONSISTENCY - COARSE-GRAINED SOILS Relative Density Standard Penetration Dames& Moore Sampler Dames &Moore Sampler Resistance (140-pound hammer) (300-pound hammer) 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 SOILS Consistency Standard Penetration Dames& Moore Sampler Dames& Moore Sampler Unconfined Compressive Resistance (140-pound hammer) (300-pound hammer) Strength (tsf) 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 SOIL CLASSIFICATION NAME Name and Modifier Terms Constituent Percentage GRAVEL, SAND >50% sandy, gravelly 30 - 50% silty, clayey 15 - 50% Coarse-grained some (gravel, sand) 15 -30% some (silt, clay) trace(gravel, sand) 5 15% trace (silt, clay) <5% CLAY, SILT >50% silty, clayey sandy, gravelly 30 50% Fine-grained some (sand, gravel) some (silt, clay) 15 30% trace(sand, gravel) trace (silt, clay) 5 15% PEAT 50 - 100% Organic organic(soil name) 15 - 50% (soil name)with some organics 5 - 15% MOISTURE CLASSIFICATION m Term Field Test 0 dry very low moisture, dry to touch moist damp,without visible moisture c wet visible free water, usually saturated GRAIN SIZE CLASSIFICATION 0 • Description Sieve" Observed Size boulders - >12" cobbles 3" 12" gravel coarse 0.75"- 3" 0.75"- 3" � fine #4 -0.75" 0.19"-0.75" ro coarse #10-#4 0.079°- 0.19" sand medium #40-#10 0.017"-0.079" fine #200-#40 00029"-0.017" fines <#200 <0.0029" w Use of#200 field sieve encouraged A 3' [ DESIGN' £ 15575SW Sequoia Parkway-Suite 100 SOIL CLASSIFICATION SYSTEM AND GUIDELINES TABLE A-2 f6 Portland OR 97224 Z Off 503.968.8787 Fax 503.968.3068 ...... ..........._.............,.....«.+.euvu.ss +urr++Mt .sxFisWNf➢JNi43NMiiNWHffi1NW3MNaN7HNAia/ J }.xnr..,. ..w.t..r. ..a,<..,.a,<. .w,ae...,.n vas.taral✓ar.uwWiW.WrrWveWwuWWyvWW+.WNMWr#dro+M W NNs/strv3 k v.svuul .+aAt.arr. ROCK CLASSIFICATION GUIDELINES HARDNESS DESCRIPTION Extremely Soft (RO) Indented by thumbnail Very Soft (R1) Can be peeled by pocket knife or scratched with finger nail Soft (R2) Can be peeled by a pocket knife with difficulty Medium Hard (R3) Can be scratched by knife or pick Hard (R4) Can be scratched with knife or pick only with difficulty Very Hard (R5) Cannot be scratched with knife or sharp pick WEATHERING DESCRIPTION Decomposed Rock mass is completely decomposed Predominantly Decomposed Rock mass is more than 50%decomposed Moderately Weathered Rock mass is decomposed locally Slightly Weathered Rock mass is generally fresh Fresh No discoloration in rock fabric JOINT SPACING DESCRIPTION Very Close Less than 2 inches Close 2 inches to 1 foot Moderate Close 1 foot to 3 feet Wide 3 feet to 10 feet Very Wide Greater than 10 feet FRACTURING FRACTURE SPACING Very Intensely Fractured Chips and fragments with a few scattered short core lengths Intensely Fractured 0.1 foot to 0.3 foot with scattered fragments intervals Moderately Fractured 0.3 foot to 1 foot with most lengths 0.6 foot Slightly Fractured 1 foot to 3 feet Very Slightly Fractured Greater than 3 feet Unfractured No fractures 0 HEALING DESCRIPTION Not Healed Discontinuity surface, fractured zone, sheared material or filling not re-cemented Partly Healed Less than 50%of fractured or sheared material 7,3 Moderately Healed Greater than 50%of fractured or sheared material Totally Healed All fragments bonded [ DESIGN' 15575 SW Sequoia Parkway-Suite 100 ROCK CLASSIFICATION GUIDELINES TABLE A-3 Portland OR 97224 Off 503.968.8787 Fax 503.968.3068 v w DEPTH u z JMISTUR FEET MATERIAL DESCRIPTION w LU w Q •ONOTENT%E COMMENTS tqe w I— TP-1 0.0 0 50 100 Medium stiff, brown SILT with trace rootlets; moist (2- to 4-inch-thick root r 0.8 \zone, till zone to 0.75 foot). very stiff, brown gray SILT with ® PP= 3.0 tsf 2.5— PP traceStiffto fine sand; moist. with orange-brown iron nodules at 2.0 PP ® PP=2.0 tsf feet with trace subangular cobbles and single s.o— boulder at 3.0 feet grades to very stiff and dark brown with trace fine to coarse gravel and single boulder (12-inch diameter) at 4.0 feet grades to stiff and brown with trace fine 7.5— sand at 4.5 feet 10.0— No groundwater seepage observed 1 2.5 12 5 • to the depth explored. Exploration completed at 12.5 feet. No caving observed to the depth explored. 15.0— TP-2 0 so 100 0.0 0 s0 l00 Stiff, brown SILT with trace rootlets; \moist (2- to 4-inch-thick root zone, till 1 0 PP= 1.5 tsf zone to 1.0 foot). I PP • Stiff, brown SILT with trace fine gravel 2.5— and roots; moist; black charcoal fragments; subrounded to subangular ® • PP= 3.0 tsf gravel. PP PP=4.0 tsf grades to very stiff to hard with orange 5.0— and gray mottles, black nodules, and Excavation becomes hard below trace sand at 3.0 feet 5.0 feet. Q - ▪ 7.5— No groundwater seepage observed to the depth explored. r 1 grades to some subangular, weathered, 8.3 ® No caving observed to the depth \basalt cobbles at 8.0 feet 8.5 explored. Extremely soft to very $oft (RO-R1), • lo.o— brown BASALT; decomposed to intensely weathered; hard, angular gravel- to o boulder-size rock fragments. Exploration completed at 8.5 feet due to refusal on basalt. Q 2• 15.0— Q u 50 100 a EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:KOU COMPLETED:06/19/06 a. EXCAVATION METHOD:excavator(see report text) ° v TIGARDTUAL-15-01 TEST PIT ▪ GEODESIGNZ 15575 SW Sequoia Parkway-Suite 100 THORPE PROPERTY w Portland FRax x7224503 JULY 2006 FIGURE A-1 Off 503.968.8787 rax 503.968.3068 TIGARD,OR v Z o O= U w DEPTH u ~~ Z FEET a MATERIAL DESCRIPTION w L N 2 •ONOTENT%E COMMENTS v w Iw— vvs TP-3 o.0 0 50 100 Medium stiff, dark brown SILT with trace \r000tl ts;ne moist (topsoil, 4-inch-thick root 1 0 PP ® PP=0.5 tsf ).Very stiff, brown SILT with trace roots; PP=2.25 tsf 2.5— moist. PP ® • becomes very stiff to hard and brown PP ® PP=4.0 tsf with orange-gray mottles and trace sand Excavating becomes hard below at 3.0 feet 4.0 feet. 5.0— 7.5— • No groundwater seepage observed H I Extremely soft to very soft (RO-Rl), 9.0X to the depth explored. 10.0- brown BASALT; decomposed to intensely 9.5 No caving observed to the depth weathered; hard, angular gravel- to explored. boulder-size rock fragments. Exploration completed at 9.5 feet due to 12.5— refusal on basalt. 1 5.0— TP-40 50 100 o.0 0 50 100 Soft to medium stiff, brown SILT; moist '",(topsoil, 4-inch-thick root zone). 1.0 PP PP=0.75 tsf Very stiff to hard, brown-red SILT with trace sand and rootlets; moist. ® PP= 3.0 tsf 2.5— PP • grades to brown with orange and gray PP PP=4.0 tsf mottles without rootlets at 3.5 feet ® • 5.0— Excavating becomes hard below 5.0 feet. a 7.5— z No groundwater seepage observed . 1111 Extremely soft to very soft (RO-Rl), 80 to the depth explored. brown BASALT; decomposed to intensely 8.5 No caving observed to the depth weathered; hard, angular gravel- to explored. Z 10.0- boulder-size rock fragments. Exploration completed at 8.5 feet due to o refusal on basalt. u 12.5— a. F- H cc1 5.0— cc 0 50 100 a EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:KOU COMPLETED:06/19/06 EXCAVATION METHOD:excavator(see report text) ° u TIGARDTUAL-15-01 TEST PIT GEODESIGNZ W15575 6W Sequoia nd ORParkway7224 Suite 100 THORPE PROPERTY Portland Fax 04 JULY 2006 FIGURE A-2 H Off 503.968.8787 Fax 503.968.3068 TIGARD, OR - ...., ....»....._......n....aw rkw'nsear s.wwrcw..uUa+d+RxN.StCWtNail:NaNJii.Hx tNf3eaadiaM ...r..... ............. ......r, .r.r..++.a x:..sirlr r..rxra•• tef sctxea .rraa...• saa .....,. •r...r...,. .. ...... u z O O= U u� DEPTH u Q a Z a •MOISTURE FEET a MATERIAL DESCRIPTION w Lu w Q CONTENT% COMMENTS u w I— to TP-5 0.0 0 50 100 Medium stiff, brown SILT with trace organics (rootlets); dry to moist (2- to 4- 1 0ig inch-thick root zone, till zone to 1.0 pp PP= 3.0 tsf - foot). 2.5— Very stiff to hard, brown to red SILT with PP PP= 3.5 tsf trace fine sand and fine roots; moist. PP ® I PP=4.0 tsf with orange-gray mottles without rootlets at 3.0 feet Excavating becomes hard below 5.0— 4.5 feet. 7.5— 10.0— No groundwater seepage observed 11 I Extremely soft to very soft (RO-Rl), 11 5 ® • to the depth explored. 12.5— brown BASALT; decomposed to intensely 12.0 No caving observed to the depth weathered; hard, angular gravel- to explored. boulder-size rock fragments. Exploration completed at 12.0 feet due 15.0— to refusal on basalt. 0 50 100 TP-6 0.0 0 so 100 Medium stiff, dark brown SILT with trace DD • DD= 81 pct rootlets; dry to moist (2- to 4-inch-thick 0.7 - \root zone, till zone to 0.7 foot). PP PP=2.5 tsf Very stiff, brown SILT with trace fine 2.5— roots; moist. with orange-gray mottles at 3.0 feet PP PP= 3.5 tsf - ® • 5.0— o _ N n — W 1- 0 7.5— 1-- with trace fine sand below 8.0 feet o lo.o— z u w 0 ° No groundwater seepage observed 12.5 I it I Extremely soft to very soft (RO-Rl), 12.0 ® to the depth explored. v brown BASALT; decomposed to intensely 12.5 No caving observed to the depth weathered; hard, angular gravel- to explored. boulder-size rock fragments. z Exploration completed at 12.5 feet due ,2 15.0— to refusal on basalt. a u 0 50 100 F u EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:KOU COMPLETED:06/19/06 o. cc `. EXCAVATION METHOD:excavator(see report text) ° v TIGARDTUAL-1 5-01 TEST PIT GEODESIGNZ Lo 75575 SW Sequoia Parkway-Suite lxx THORPE PROPERTY w Portland0R97224 JULY 2006 FIGURE A-3 Off 503.968.8787 Fax 503.968.3068 TIGARD, OR Z u DEPTH L.) Q�a Z a •MOISTURE FEET a MATERIAL DESCRIPTION w w N g CONTENT% COMMENTS w Q cc —J I— in TP-7 0.0 0 50 100 ` Medium stiff, dark brown SILT with trace rootlets; dry(topsoil, 2-inch-thick root - \zone). '° PP PP=3.0 tsf Very stiff to hard, brown SILT; moist. 2.5— grades to dark brown at 2.0 feet ® • 5.0— PP PP= 3.5 tsf 7.5— encountered single, weathered basalt - boulder (weathered basalt clast, 24 x 18 x 8 inches) at 7.0 feet No groundwater seepage observed 10.0 LI Extremely soft to very soft (RO-R1), 9.8 • to the depth explored. No caving observed to the depth brown BASALT; decomposed to intensely 10.0 explored. weathered; hard, angular gravel- to boulder-size rock fragments. 12.5— Exploration completed at 10.0 feet due to refusal on basalt. 15.0— TP-8 0 50 100 0 50 100 0.0 rt Medium stiff, dark brown SILT with trace -- \to some organics and roots; moist r 0.8 PP PP=2.0 tsf (topsoil). Very stiff to hard, brown SILT with trace 2.5— rootlets and roots; moist. - few decomposed roots (4-to 5-inch diameter) at 2.7 feet PP El • PP=3.0 tsf F without rootlets at 4.0 feet PP PP= 3.5 tsf i6• 5.0— 0 with trace fine sand at approximately 6.0 feet o 7.5— El • Z No groundwater seepage observed 1 ' Extremely soft to very soft (RO R1), 8.3 to the depth explored. No caving observed to the depth brown BASALT; decomposed to intensely 8.5 lo.o— weathered; hard, angular gravel- to• explored. z boulder-size rock fragments. w Exploration completed at 8.5 feet due to 0 refusal on basalt. 12.5- 0 Q 1- 15.0— a ✓ 0 50 100 1 EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:KOU COMPLETED:06/19/06 a EXCAVATION METHOD:excavator(see report text) V TIGARDTUAL-15-01 TEST PIT • G EODESIGN� 15575 SW Sequoia Parkway.Suite 100 THORPE PROPERTY Portland8 FaxR 5043 JULY 2006 FIGURE A-4 F— Off 503.9 Fax 503.968.3068 TIGARD,OR L., z DEPTH u Q a Z a •MOISTURE FEET MATERIAL DESCRIPTION w w N 2 CONTENT% COMMENTS < -J u' < cc cc w I-- cn TP-9 o.0 0 50 100 Medium stiff, dark brown SILT with trace - 'to some organics and roots; moist 0.7 (topsoil, 2- to 4-inch-thick root zone). pp PP= 1.5 tsf Stiff to very stiff, brown SILT; moist. 2.5— PP ® • PP=2.0 tsf ( I with trace roots (1- to 1%z-inch diameter) 3.2 ♦ No groundwater seepage observed ',I \at 3.0 feet to the depth explored. Extremely soft to very soft (RO-Rl), 40 No caving observed to the depth 5.0— brown BASALT; decomposed to intensely explored. weathered; hard, angular gravel- to boulder-size rock fragments. Exploration completed at 4.0 feet due to 5- refusal on basalt. 7.10.0— 12.5— 15.0— TP-10 ° 50 00 o.0 0 50 100 Medium stiff, dark brown SILT with trace °5 (to some organics and roots; moist (topsoil, 2-inch-thick root zone). Very stiff, brown SILT with dark brown PP=2.25 tsf 2.5— mottles; moist. PP ® with trace fine rootlets at 2.0 feet PP PP= 3.25 tsf • F to 5.0— O r. with trace fine sand at 6.0 feet Li H • a • 7.5— z _ R 0 Z lo.o— Z _ becomes red-brown at 10.0 feet No groundwater seepage observed o III 1 Extremely soft to very soft (RO-R1), 10 5 ® to the depth explored. 8 brown BASALT; decomposed to intensely 11.0 No caving observed to the depth weathered; hard, angular gravel- to explored. 12.5— boulder-size rock fragments. Exploration completed at 1 1.0 feet due to refusal on basalt. a - H O 1 5.0— a 0 50 100 F L., a EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:KOU COMPLETED:06/19/06 d LU d EXCAVATION METHOD:excavator(see report text) N ° v TIGARDTUAL-1 5-01 TEST PIT • GEODESIGN_ wH 15676 SW Sequoia Parkway-Suite 100 THORPE PROPERTY Portland FRax x7504 3 JULY 2006 FIGURE A-5 f— Off 503.968.8787 Fax 503.968.3068 TIGARD, OR u z 0 0= u DEPTH u I- z MISTUE FEET d MATERIAL DESCRIPTION w 0 I g •ONOTENTR% COMMENTS w F- TP-1 1 o.0 0 50 100 Stiff, dark brown SILT with trace rootlets; '''',moist (topsoil, 4-inch-thick root zone). 1 0 PP= 1.5 tsf Very stiff, brown SILT; moist. PP ® • PP=2.0 tsf PP 2.5- with orange-gray mottles at 2.0 feet PP PP=2.5 tsf 5.0- 7.5- with trace fine sand at 7.0 feet 10.0 III I Extremely soft to very soft (RO Rl), 9.5 • No groundwater seepage observed to the depth explored. brown BASALT; decomposed to intensely 10.0 No caving observed to the depth weathered; hard, angular gravel- to explored. boulder-size rock fragments. Exploration completed at 10.0 feet due 12.5- to refusal on basalt. 15.0- TP-12 0 50 100 0.0 0 50 100 Stiff, dark brown SILT with trace rootlets; moist (4-inch-thick root zone, till zone to , 0 pp PP=2.0 tsf \1.0 foot). Very stiff, brown SILT with dark brown pp PP=2.5 tsf 2.5- and black mottles and trace fine roots; PP PP=2.25 tsf moist. without roots at 3.0 feet PP ® • PP=2.75 tsf ca 5.0 with trace fine sand at 5.0 feet No groundwater seepage observed II I \Extremely soft to soft RO-Rl7.5 very ( ), 7.0 ® to the depth explored. Z brown BASALT; decomposed to intensely 7.5 No caving observed to the depth weathered; hard, angular gravel- to explored. boulder-size rock fragments. Exploration completed at 7.5 feet due to z 10.0- refusal on basalt. w 0 L7 u 12.5- 0 H a 15.0 a 0 50 100 F- u EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:KOU COMPLETED:06/19/06 d EXCAVATION METHOD:excavator(see report text) v TIGARDTUAL-15-01 TEST PIT G EODESIGNZ N 15575 SW Sequoia Parkway-Suite 100 688787Portland FaxR 224 503 DULY 2006 THORPE PROPERTY FIGURE A-6 H Off 503.968.8787 Fax 503.968.3068 TIGARD, OR it APPENDIX C Site-Specific Seismic Hazard Evaluation APPENDIX C SITE-SPECIFIC SEISMIC HAZARD STUDY GENERAL GRI completed a site-specific seismic-hazard study for the new Art Rutkin Elementary School in Portland, Oregon. The purpose of this study was to evaluate the potential seismic hazards associated with regional and local seismicity. The site-specific seismic hazard evaluation is intended to meet the requirements of the 2014 Oregon Structural Specialty Code (OSSC), which is based on the 2012 International Building Code (IBC). Seismic design in accordance with the 2012 IBC is based on the American Society of Civil Engineers (ASCE) Document 7-10, Minimum Design Loads for Buildings and Other Structures (ASCE 7-10). Our site- specific seismic hazard evaluation was based on the potential for regional and local seismic activity, as described in the existing scientific literature, and the subsurface conditions at the site, as disclosed by the geotechnical explorations completed for the project. Specifically, our work included the following tasks: 1) A detailed review of available literature, including published papers, maps, open-file reports, seismic histories and catalogs, and other sources of information regarding the tectonic setting, regional and local geology, and historical seismic activity that might have a significant effect on the site. 2) Compilation, examination, and evaluation of existing subsurface data gathered at the site, including classification and laboratory analyses of soil samples. This information was used to prepare a generalized subsurface profile for the site. 3) Identification of potential seismic sources appropriate for the site and characterization of those sources in terms of magnitude, distance, and acceleration response spectra. 4) Office studies based on the generalized subsurface profile and controlling seismic sources resulting in conclusions and recommendations concerning: a. specific seismic events and characteristic earthquakes that might have a significant effect on the project site; b. the potential for seismic energy amplification and liquefaction or soil-strength loss at the site; and c. site-specific acceleration response spectra for design of structures at the site. This appendix describes the work accomplished and summarizes our conclusions and recommendations. GEOLOGIC SETTING General On a regional scale, the site lies at the northern end of the Willamette Valley, a broad, gently deformed, north-south-trending topographic feature separating the Coast Range to the west from the Cascade Mountains to the east. The site is located approximately 69 km inland from the rupture zone of the Cascadia Subduction Zone (CSZ), an active convergent-plate boundary along which remnants of the Farallon Plate (the Gorda, Juan de Fuca, and Explorer plates) are being subducted beneath the western edge of the North American G ROC-1 continent. The subduction zone is a broad, eastward-dipping zone of contact between the upper portion of the subducting slabs and the overriding North American Plate, as shown on Figure 1 C. On a local scale, the site is located in the Tualatin Basin, a large, well-defined, northwest-trending syncline bounded by high-angle, northwest-trending, right-lateral strike-slip faults, some of which are considered to be seismogenic. The geologic units in the area are shown on the Local Geologic Map, Figure 2C. The distribution of nearby Quaternary faults is shown on the Local Fault Map, Figure 3C. Information regarding the continuity and potential activity of these faults is lacking due largely to the scale at which geologic mapping in the area has been conducted and the presence of thick, relatively young, basin-filling sediments that obscure underlying structural features. Additional faults may be present within the basin, but clear stratigraphic and/or geophysical evidence regarding their location and extent is not presently available. Additional discussion regarding crustal faults is provided in the Local Crustal Event section below. Because of the proximity of the site to the CSZ and its location within the Tualatin Basin, three distinctly different sources of seismic activity contribute to the potential for the occurrence of damaging earthquakes. Each of these sources is generally considered to be capable of producing damaging earthquakes. Two of these sources are associated with the deep-seated tectonic activity related to the subduction zone; the third is associated with movement on the local, relatively shallow structures within and adjacent to the Tualatin Basin. Subsurface and Geologic Conditions Published geologic mapping indicates the site is mantled with residual soils produced from the weathering of the underlying Columbia River Basalt (Madin, 2004). These residual soils typically consist of brown to red-brown silt and clay soils of relatively high plasticity that exhibit relict structures of the weathered rock. The weathering profile of the basalt grades from residual soil to hard rock with increasing depth within a given flow. SEISMICITY General The available information indicates the potential seismic sources that may affect the site can be grouped into three independent categories: subduction-zone events related to sudden slip between the upper surface of the Juan de Fuca Plate and lower surface of the North American Plate, subcrustal events related to deformation and volume changes within the subducted mass of the Juan de Fuca Plate, and local crustal events associated with movement on shallow, local faults within and adjacent to the Portland Basin. Each of these sources is considered capable of producing damaging earthquakes in the Pacific Northwest. However, there are no historical records of significant (i.e., moment magnitude (Mw) >6.0) subcrustal or intraslab earthquakes. Based on review of historical records and evaluation of U.S. Geological Survey (USGS) National Seismic Hazard Maps (NSHMs),the two primary types of seismic sources at the site are the megathrust CSZ and local crustal faults. Cascadia Subduction Zone(CSZ) Written Japanese tsunami records suggest a great CSZ earthquake occurred in January 1700 (Atwater et al., 2015). Geological studies suggest great megathrust earthquakes have occurred repeatedly in the past 7,000 years (Atwater et al., 1995; Clague, 1997; Goldfinger et al., 2003; and Kelsey et al., 2005), and geodetic studies (Hyndman and Wang, 1995; and Savage et al., 2000) indicate rate of strain accumulation consistent GRAC-2 with the assumption that the CSZ is locked beneath offshore northern California, Oregon, Washington, and southern British Columbia(Fluck et al., 1997;and Wang et al.,2001). Numerous geological and geophysical studies suggest the CSZ may be segmented(Hughes and Carr, 1980;Weaver and Michaelson, 1985;Guffanti and Weaver, 1988; Goldfinger, 1994; Kelsey and Bockheim, 1994; Mitchell et al., 1994; Personius, 1995; Nelson and Person ius, 1996; and Witter, 1999), but the most recent studies suggest for the last great earthquake in 1700, most of the subduction zone ruptured in a single Mw 9 earthquake (Satake et al., 1996; Atwater and Hemphill-Haley, 1997;and Clague et al.,2000). Published estimates of the probable maximum size of subduction-zone events range from Mw 8.3 to >Mw 9. Numerous detailed studies of coastal subsidence, tsunamis, and turbidites yield a wide range of recurrence intervals, but the most complete records (>4,000 years) indicate intervals of about 350 to 600 years between great earthquakes on the CSZ (Adams, 1990; Atwater and Hemphill-Haley, 1997; Witter, 1999; Clague et al., 2000; Kelsey et al., 2002; Kelsey et al., 2005; and Witter et al., 2003). Tsunami inundation in buried marshes along the Washington and Oregon coast and stratigraphic evidence from the Cascadia margin support these recurrence intervals (Kelsey et al.,2005;and Goldfinger et al.,2003). Goldfinger et al. (2003,2012,and 2016)evaluated turbidite evidence for 20 earthquakes that ruptured the entire CSZ over the past 10,000 years and about 20 Mw 8 earthquakes that only ruptured along the southern portion of the CSZ and developed a model for recurrence of CSZ Mw 8 to Mw 9 earthquakes. The USGS probabilistic analysis assumes four potential locations (three alternative down-dip edge options and one up-dip edge option) for the eastern edge of the earthquake rupture zone for the CSZ, as shown on Figure 4C. As discussed in Petersen et al. (2014), the 2014 USGS mapping effort represents the 2014 CSZ source model with the full CSZ ruptures with moment magnitudes from Mw 8.6 to Mw 9.3 supplemented by partial ruptures with smaller magnitudes from Mw 8.0 to Mw 9.1. The partial ruptures were accounted for using a segmented model and unsegmented model. The magnitude-frequency distribution showing the contributions to the earthquake rates from each of the models and how the rates vary along the fault is presented on Figure 5C. In general, the earthquake rates along the CSZ are dominated by the full- characteristic CSZ ruptures, with one event in 526 years (Mw 8.6 to Mw 9.3 earthquakes likely occur more often than the smaller,segmented ruptures). Therefore, in our opinion,the CSZ event should be represented by an earthquake of Mw 9.0 at a focal depth of 30 km and a rupture distance of about 69 km. Local Crustal Event Sudden crustal movements along relatively shallow, local faults in the project area, although rare, have been responsible for local crustal earthquakes. The locations of and general information regarding Quaternary faults (i.e., those that have experienced movement during the last 2.6 million years and are considered to be potentially active) are available through the USGS Earthquake Hazards Program. The precise relationship between specific earthquakes and individual faults is not well-understood since few of the faults in the area are expressed at the ground surface and the foci of the observed earthquakes have not been located with precision. The history of local seismic activity is commonly used as a basis for determining the size and frequency to be expected of local crustal events. Although the historical record of local earthquakes is relatively short (the earliest reported seismic event in the area occurred in 1920), it can serve as a guide for estimating the potential for seismic activity in the area. Based on fault mapping conducted by the USGS (USGS, 2014),there are about seven faults within 25 km of the project site: the Canby-Mollala Fault at about 5 km from the site, the Bolton Fault at about 12.2 km from the site, the Helvetia Fault at about 13.4 km from the site; the Newberg Fault at about 13.4 km from the site, GRU C-3 the Portland Hills Fault at about 17.1 km from the site, the Gales Creek Fault Zone at about 24 km from the site, and the Grant Butte Fault at about 24.8 km from the site. However, the USGS only considers the Portland Hills Fault to be an active,contributing source in their Probabilistic Seismic Hazard Analysis(PSHA). The Portland Hills Fault is considered to be a reverse fault that dips to the southwest, with a total fault length of approximately 50 km and a characteristic earthquake magnitude of Mw 7.0. Based on our review of the USGS Quaternary Fault and Fold Database of the United States, it is our opinion a seismic event occurring on the Portland Hills Fault should be represented by a source-to-site distance of approximately 17.1 km and a corresponding characteristic earthquake magnitude of Mw 7.0. CODE BACKGROUND AND DESIGN RESPONSE SPECTRUM General The ASCE 7-10 seismic hazard levels are based on a Risk-Targeted Maximum Considered Earthquake (MCER) with the intent of including the probability of structural collapse. Based on generalized building fragility curves, seismic design of a structure using the probabilistic MCER represents a targeted risk level of 1% in 50 years probability of collapse in the direction of maximum horizontal response. In general,these risk-targeted ground motions are developed by applying adjustment factors of directivity and risk coefficients to the 2% probability of exceedance in 50 years (2,475-year return period hazard level) ground motions developed from the 2008 USGS probabilistic seismic hazard maps. The risk-targeted probabilistic values are also subject to a deterministic check, which is computed from the models of earthquake sources and ground- motion propagation that form the basis of the 2008 USGS NSHMs. ASCE 7-10 defines the site-specific deterministic MCER ground motions in terms of 84th-percentile, 5%-damped response spectral acceleration in the direction of maximum horizontal response. The MCER ground motions are taken as the lesser of the probabilistic and deterministic spectral accelerations. Site Response The ASCE 7-10 design methodology uses two spectral response acceleration parameters, Ss and Si, corresponding to periods of about 0.2 and 1.0 second to develop the MCER response spectrum for Site Class B/C, or bedrock conditions. The Ss and Si parameters for the site located at the approximate latitude and longitude coordinates of 45.4071° N and 122.8454° W are 0.95 and 0.42 g, respectively. To establish the ground-surface MCER spectrum,these bedrock spectral parameters are adjusted for underlying soil conditions at the site using the short- and long-period site amplification coefficients, Fa and Fv. Based on the results of the explorations completed for this project, the soil profile at the site is representative of Site Class C conditions. Site coefficients Fa and Fvof 1.02 and 1.38, respectively, were used to develop the Site Class C ground-surface MCER response spectra. The design response spectrum in accordance with ASCE 7-10 is developed by taking two-thirds of the MCER response spectrum. The MCER and design response spectral values are tabulated below. RECOMMENDED MCERAND DESIGN RESPONSE SPECTRA,5%DAMPING Period, MCER-Level Design-Level seconds Response Spectral Values,g Response Spectral Values,g 0.01 0.44 0.29 0.12 0.97 0.65 0.60 0.97 0.65 GRU C-4 Period, MCER-Level Design-Level seconds Response Spectral Values,g Response Spectral Values,g 0.80 0.73 0.49 1.00 0.58 0.39 2.00 0.29 0.19 3.00 0.19 0.13 4.00 0.15 0.10 CONCLUSIONS The ASCE 7-10 design methodology uses two mapped spectral acceleration parameters, Ss and Si, corresponding to periods of 0.2 and 1.0 second to develop the MCER earthquake. The Ss and Si parameters for the site located at the approximate latitude and longitude coordinates of 45.4071° N and 122.8454° W are 0.95 and 0.42 g, respectively. We recommend use of the Site Class C design spectrum for design of the proposed improvements. References Adams, J., 1990, Paleoseismicity of the Cascadia subduction zone: Evidence from turbidites off the Oregon-Washington margin: Tectonics,vol.9,no.4,pp.569-583. American Society of Civil Engineers,2016b,ASCE 7-16,Minimum design loads for buildings and other structures,Draft Copy,ASCE, Reston,Virginia. Atwater,B.F.,and Hemphill-Haley,E.,1997,Recurrence intervals for great earthquakes of the past 3,500 years at northeastern Willapa Bay,Washington,U.S.Geological Survey, Professional Paper 1576, 108 p. Atwater, B. F., Nelson,A. R., Clague,J.J.,Carver,G.A.,Yamaguchi, D. K., Bobrowsky, P.T., Bourgeois,J., Darienzo,M. E.,Grant, W. C., Hemphill-Haley, E., Kelsey,H. M.,Jacoby,G.C., Nishenko, S. P., Palmer,S. P., Peterson, C. D., and Reinhart, M. A., 1995, Summary of coastal geologic evidence for past great earthquakes at the Cascadia subduction zone: Earthquake Spectra,vol. 11,no. 1,pp. 1-18. Atwater, B. F., Musumi-Rokkaku, S., Satake, K., Tsuji, Y., Ueda, K., and Yamaguchi, D. K., 2015, The orphan tsunami of 1700— Japanese clues to a parent earthquake in North America,2nd ed., U.S.Geological Survey,Professional Paper 1707,Seattle, University of Washington Press, 135 p. Clague,J.J., 1997,Evidence for large earthquakes at the Cascadia subduction zone: Reviews of Geophysics,vol. 35,no.4,pp.439- 460. Clague, J. J., Atwater, B. F., Wang, K., Wang, Y., and Wong, I., 2000, Penrose conference report—Great Cascadia earthquake tricentennial:GSA Today,vol. 10,no. 11, pp. 14-15. Fluck, P., Hyndman, R. D., and Wang, K., 1997, Three-dimensional dislocation model for great earthquakes of the Cascadia subduction zone:Journal of Geophysical Research,vol. 102,no. B9, pp.20,539-20,550. Goldfinger, C., 1994, Active deformation of the Cascadia Forearc—Implications for great earthquake potential in Oregon and Washington,Oregon State University, unpublished dissertation. Goldfinger,C.,Nelson,C.H.,and Johnson,J.E.,2003,Holocene earthquake records from the Cascadia subduction zone and northern San Andreas fault based on precise dating of offshore turbidites:Annual Review of Earth and Planetary Sciences 31,pp.555- 577. Goldfinger,C.,Nelson,C.H.,Morey,A.,Johnson,J.E.,Gutierrez-Pastor,J.,Eriksson,A.T.,Karabanov,E.,Patton,J.,Gracia,E.,Enkin, R., Dallimore, A., Dunhill, G., and Vallier, T., 2012, Turbidite event history: Methods and implications for holocene paleoseismicity of the Cascadia Subduction Zone, U.S.Geological Survey, Professional Paper 1661. Goldfinger, C., Galer, S., Beeson,J., Hamilton, T., Black, B., Romsos, C., Patton,J., Nelson, C. H. Hausmann, R., and Morey, A., 2016,The importance of site selection,sediment supply,and hydrodynamics:A case study of submarine paleoseismology on the northern Cascadia margin,Washington USA:Marine Geology In Press, DOI: 10.1016/j.margeo.2016.06.008. GRfl C-5 Guffanti,M.,and Weaver,C.S., 1988,Distribution of Late Cenozoic volcanic vents in the Cascade Range-Volcanic arc segmentation and regional tectonic considerations:Journal of Geophysical Research,vol.93, no. B6,pp.6,513-6,529. Hughes,J.M.,and Carr,M.J., 1980,Segmentation of the Cascade volcanic chain:Geology,vol.8,pp. 15-17. Hyndman, R. D., and Wang, K., 1995, The rupture zone of Cascadia great earthquakes from current deformation and the thermal regime: Journal of Geophysical Research,vol. 100,no. B11,pp.22,133-22,154. Kelsey,H.M.,and Bockheim,J.G.,1994,Coastal landscape evolution as a function of eustasy and surface uplift rate,Cascadia margin, southern Oregon:Geological Society of America Bulletin,vol. 106,pp.840-854. Kelsey, H.M., Nelson,A. R., Hemphill-Haley, E.,and Witter, R.C.,2005,Tsunami history of an Oregon coastal lake reveals a 4600 yr record of great earthquakes on the Cascadia subduction zone: Geological Society of America Bulletin,v. 117, no. 7-8, pp. 1009-1032. Kelsey, H. M., Witter, R.C.,and Hemphill-Haley, E.,2002, Pl.-boundary earthquakes and tsunamis of the past 5500 yr, Sixes River estuary,southern Oregon:Geological Society of America Bulletin,vol. 114,no. 3,pp.298-314. Mitchell, C. E. Vincent, P., Weldon, R.J. Ill, and Richards, M. A., 1994, Present-day vertical deformation of the Cascadia margin, Pacific Northwest, United States: Journal of Geophysical Research,vol.99,no. B6,pp. 12,257-12,277. Madin,I. P.,2004, Preliminary digital geologic compilation map of the greater Portland urban area,Oregon:Oregon Department of Geology and Mineral Industries,Open-File Report 0-04-02,scale 1:24,000. Nelson, A. R., and Personius, S. F., 1996, Great-earthquake potential in Oregon and Washington-An overview of recent coastal geologic studies and their bearing on segmentation of Holocene ruptures, central Cascadia subduction zone, in Rogers, A.M., Walsh, T.J., Kockelman, W.J., and Priest, G.R., eds., Assessing earthquake hazards and reducing risk in the Pacific Northwest, U.S.Geological Survey, Professional Paper 1560,vol. 1,pp. 91-114. Personius, S. F., 1995, Late Quaternary stream incision and uplift in the forearc of the Cascadia subduction zone,western Oregon: Journal of Geophysical Research,vol. 100,no.B10,pp. 20,193-20,210. Petersen,M. D.,Moschetti,M.P.,Powers,P.M.,Mueller,C.S., Haller, K.M.,Frankel,A. D.,Zeng,Y.,Rezaeian,S., Harmsen,S.C., Boyd, O. S., Field, N., Chen, R., Rukstales, K. S., Nico, L., Wheeler, R. L., Williams, R. A., and Olsen, A. H., 2014, Documentation for the 2014 update of the United States national seismic hazard maps, U.S.Geological Survey,Open-File Report 2014-1091,243 p.,obtained at: http://dx.doi.org/10.3133/ofr20141091. Satake, K., Shimazaki, K., Tsuji, Y., and Ueda, K., 1996, Time and size of a giant earthquake in Cascadia inferred from Japanese tsunami records of January 1700: Nature,vol. 379,pp.246-249. Savage,J.C.,Svarc,J. L., Prescott,W. H.,and Murray,M. H.,2000, Deformation across the forearc of the Cascadia subduction zone at Cape Blanco,Oregon: Journal of Geophysical Research,vol. 105, no. B2,pp. 3,095-3,102. U.S.Geological Survey,2014, Unified hazard tool lookup by latitude, longitude,accessed 04/11/17 from USGS website: https://earthquake.usgs.gov/hazards/interactive/. Wang,Y.,He,J.,Dragert,H.,and James,T.S.,2001,Three-dimensional viscoelastic interseismic deformation model for the Cascadia subduction zone: Earth, Planets,and Space,vol. 53,pp.295-306. Weaver,C.S.,and Michaelson,C.A., 1985,Seismicity and volcanism in the Pacific Northwest-Evidence for the segmentation of the Juan de Fuca PI.: Geophysical Research Letters,vol. 12,no.4,pp.215-218. Witter, R. C. 1999, Late Holocene Paleoseismicity, tsunamis and relative sea-level changes along the south-central Cascadia subduction zone,southern Oregon:University of Oregon, unpublished PhD dissertation, 178 p. Witter,R.C.,Kelsey,H.M.,and Hemphill-Haley,E.,2003,Great Cascadia earthquakes and tsunamis of the past 6700 years,Coquille River estuary,southern coastal Oregon: Geological Society of America Bulletin,vol. 115,no. 10, pp. 1,289-1,306. GRO _ C6 Q ! Cascadia Subduction Zone Setting �' Pc� 130° � 126° 122°W T�doR tj �V 52°N NORTH AMERICA NORTH AMERICAN PLATE aL%.'�` Q '- PLATE _ British i � � � � � Columbia � A. Eck/EXPLORERA , 0 PACIFIC PLATE �� J f f-`', 11 PLATE Vancouver / la itl. d(eP oD/il N0ak0. i.? or 'a f IUAN OE FUCA /-\ 1 48° J PLATE , ' n0 ll, Seattle )A iT cc) 44 Washington :.; .—— ,.. .�_:_- --..,.--- 1 / 6 E`� '—"`---i► Juan de Fuca Plate a' • JUAN DE FUCA o Portland 'Jm / PLATE ] n Luekea Zone Mngma 7 c Q7a U A 44° CASCADIASUBDUCIION ZONE SEEPING,TSUNAMI INUNDATION MAPS,OREGON DEPARTMENT OF GEOLOGY AND MINERAL INDUSTRY,2013 �P, „ Oregon 2 Y °,ye m A V PACIFIC PLATE -..../.... _>A --- -- m ` a / d A a GORDA CJ PLATE California DEFORMATION 0 200 km Mendocino Fault G� 40° R k\I` - s A TECTONIC MAP OF PACIFIC NORTHWEST,SHOWING ORIENTATION AND EXTENT OF CASCADIA SUBDUCTION ZONE MODIFIED FROM DRAGERT AND OTHERS,1999) rill Rp TECTONIC SETTING SUMMARY APR.2019 JOB NO.5970-K FIG. IC >., .J s' ~V_ \•v Tc ,.. T`r. iN ` t� - „ ..-.•. ,� x .a�r� s r� t Z'. rd = ��111, t p�� ..:7:,44L: �ii� ♦ . ' i x 1 •\ 4s� �, Ear r;;..i-.,,... ..1...,...E0ir vt �' 4Tan;, imir ,% 0IFT'', 1_ a+ .a ? ' + r - ♦ r+ s • f . ,,, t u Ttv eY va on n 'irti r, 1 kik v• :: - ♦ i t '`.(' b@ FnFIq I L 7 Ni,U' , To '' N\ t - . , Lr L ,. . ...I. /;,„. . . ..... ,..:,,„i. '�. Y �,\ t T9 A' r. 1 iit �� • 7\w bt f s t� � 1 ( vT' ''" 4 \��1 �'� '! ; tiro g� 1TOw i • = d. \ NE i t Fo st '004 _b-r� . M ,,� i ,t,nq 1 s - tr � 2L,ar.�1s. a` • _I r _ ;.� - .,., w aviT3.Y.—!1. ',,,..se - i� "r- R �t- — Y@g a+. ,:°'1' '•, ,i Tsr , ,, .fin `p a r g j- •� /4,7_S " s Tte -•. .— W.' - ,' ur.. _ _ ..r A,1&'y ��i 1.,t, aTs .-�"`y� 6...'1-_'-,-,‘'14;1-‘"'.-,':1,t;-4.k*,‘= . ,� Ctua ��r a‘ . 'AIM 'A .-r'.„i//.,'k..-.,,•.I'.7"l.i-.r,,1-Ai i,.i,;,.t 4-'.;1.I.„,,-.1.'-.%--4t,),l..i.,w''.•-i':-k:*,-.-,'„*\o,,'1t,,,:.,,:i‘i,,„.-1t.4....1.4..,.,e„1't,ry.1 4:e"1:,1.e.,;1-1,;„i.e.A 4..r1(".r.;,-0,,.1..,%,t.i.-,...a-.Th..,,„1"--e4.1..%,,1,',4,.',Tsl,,n,('iV t,L\_.1',,.,-.,-._1:-_,,1/40:- :L"1''r$-'•,.,j'-,--.---1-.,-,',', ,;*-6'.,-_--A'-.'I--_V,-,_*_,..,_-,7,,4,,-1,,", •A. yn L tr` 1 , .,:sy ,.x• e •+.0$6 FROM:M, � na � „7,',„'''.„V'-..4P,.,.4..•,,•tg,,-.'i-.,''i\A.._,'-.,T, rd„0',.,,:.,.-..0,•,.. l y i f. ` Y y^F :�j A %, 0. �(�� t?t,t, '+ +� 4 WALSH,T.L,KOROSEC M A.PHILLIPS,W M LOGAN R 1,AND SCHASSE,H.W yy . if -.3','` T ` �r 1 - ti:.'` ,,-\-' f � r) ��- ` '.L ¢} ,. 1997,GEOLOGIC MAP OF WASHING,IONSOUTHWEST QUADRANT:1:?50,000. , L ¢: / f✓" - `, t 9 4 d _ j °1 WASHINGTON DMSION OF GEOLOGY AND EARTH RESOURCES,WA 74 t ®,s ' . t --tu 6`R Tk �A c i— r ' li i t 6a R `''}rs k`_R a � �� "♦ * Ia{ -3 _ _ MACLEOD,N.5.,1991,GEOLOGIC MAP OF OREGON:U.S. iP' \\\ , WALKER, .W.,AND 'N ,.7''_,_ 4,4;1:4""i4'..:-:1., •--:.-.-, L. ;".'t'',-ft --:,7-,,-,•- 'C(t•,-, I,. im'.‘./.t.,......1..1a6,4.3..e. ,_.—_,.'i:taoirrei.7fig,._.......'-,z''",, .I.-.4,--\i\.,.,.0,-.,.....,•,.-,.'-,=.-`',1.,,"c.-+l,;'...;., --_-c-.....,'.,-i,i tiiv. T '?" - _ T� i ,a s= GEOLOCIULSURVEY ,ob, _ P♦ A*i "tq .t ( 6 1. 4.) 1 _ - cOs :. lR i,,.t'.1'.N'7''..1....",,0-'-'-9 0..,, 1 - ram. r"1 '717, as g,,, �'' -'p 1. _aN'•�.� +�,{. 4: ,\ y 1 7as - ; it Y�,- >,, R; I$ .y tL_/ 4 _ " Tfe7 ,� - .1"�° ,19 ;, j:.. 0 10 20 MILES d' ,,� w, G' ;sae � ;: 7 ,ra`' "j' ' ' ,. ( „�y ` t T i r ,. . `$ .g ft„ i,,• . , :x { ` TrbL aB 0 10 20 KILOMETERS 7A� , z. y- ,7i..��' \r,'T.< 4 _` C � * x o !t gin �. .i : ©©� Contact—Approximately located ?-••• Fau►t—Dashed where inferred;dotted where concealed;queried where doubtful;ball and bar ondowntht'ownside REGIONAL GEOLOGIC MAP :?�*A. Thrst fault—Dashed where inferred;dotted where concealed;queried where doubtful; saw ueethf on upper plate -L Strike and dip of bed APR,2019 JOB NO.5970-K FIG.2C Kelso _. _ MAP EXPLANATION TIME OF MOST RECENT SURFACE RUPTURE STRUCTURE TYPE AND RELATED FEATURES .. — Holocene(<10,000 Years)or post last gladatbn(<15,000 years(15 ka); -� Normal or kgh-angle reverse fain, r no N.tet<rupture.in Oregon to dale —0— Strike-slip feu5 - ~yam,_, = \j Gearhart '. Thrust fault — Lateots Quaternary Uoot0,(N10,post PentrE050 yeate glacia ion) Anticlinal told , Late and middle Walernary 1,50 000 Years T50 ka) '�'— L_ — Quaternary.undlterendabd(<1 600 000 Years<t 6 Ma) —1— Syncknal fold Sldk.- 1781 5 y — C ass B swnure(age o a 0 u ada) —L— Mae line idol l`- 0 Plunge duection of fold "^^^ SLIP RATE f Fault section marker '`1 - — n ram/year ��/ 1 Lr,r — 1.0.5.0 mmryear DETAILED STUDY SITES ach.3fli-a �''t 718 — 02,.O mMyeer Y3l-0 Trench site Pe j St Helens `.. — <0.2mmnea ,a,„(::::) Sbd0000 ne.wMsae l` s /d TRACE S�J• 1 � — Mosey continuous at map scab CULTURAL AND GEOGRAPHIC FEATURES am —1 MOldy tllscontnuous a[map scale Ovided Ngkwey ^"4 \\\ ----- Inferred or concealed Pnmaryasecondary road to/ 580 I1' � ,W - Permanent stream �� 78 i-s '.,877 �I `, Intermittent or stream i I I .Vancouver ,,,,,,ff Permanent n.Mem lake ach {:, 7148 - iv'` 880 867 Garibaldi - :5, ,� FAULT NUMBER NAME OF STRUCTURE ,t \\s '�- f,, , 1 7— It. .L ✓\\ 714 HELVETIA FAULT Bay City �• Forest Grove ° ' \\°��=I 715 BEAVERTON FAULT 716 CANBY-MOLALLA FAULT 882 \�s81 ��T•:t Hillsboro � as �s;8��, 879 868,E 866 718717 GALES NCREWBERG FAULTF TONE Tillamook 718 715 �` ' T �, tiT \ �` `., 'e 719 SALEMEOLA HILLS HOMOCLINE \ ,.ti 864 CLACKAMAS RIVER FAULT ZONE �78i !' 1 - �`- " 879 Portland 867 EAGLE CREEK THRUST FAULT /��// 874 868 BULL RUN THRUST FAULT .717 812 WALDO HILLS FAULT Su(++to+r R,t 0 SITE � 873 MOUNT ANGEL FAULT Area of MOUNT !'Newberg Portland map Hoop 874 BOLTON FAULT Canby 875 OATFIELD FAULT McMinnville \'i 876 EAST BANK FAULT Dayton Hubbard •`'716 877 PORTLAND HILLS FAULT 781-7 878 GRANT BUTTE FAULT Woodburn Molalla 879 DAMASCUS-TICKLE CREEK FAULT ZONE Sheridan Amity 880 IACAMAS LAKE FAULT �y'y 881 TILLAMOOK BAY FAULT ZONE - Silverton :�''`_ 873 - FROM: PERSONIUS,S.F.,AND OTHERS,2003,MAP OF QUATERNARY FAULTS AND 78'-8 FOLDS IN OREGON,USCS OPEN FILE REPORT OFR-03-095. 19 Salem I 781-9 � Dallas 71911 NIndependence, ti 872 864 .l0 (0 20 MILES P Monmouth �` ., 81 1 *184_ ' Z 871 Stayton _ i - 0 20 40,KILOMETERS �' 719 Mill City Yayitina-!1•7,,_ — LOCAL FAULT MAP APR.2019 JOB NO.5970-K FIG.3C 128'W 126`W 124 W 122"W I 1 I tilitz\, N. \ N P.4 7 P.•.., '''-----..,,,,„., *1 N I t k„,:T..rl‘'0•: • iiiiiiit NN '*" ..1S1‘..4,.„ Nv..;‘,- lkiNli .\ .„...„ :„.0t,...,.„,,_ ,. ,.... ... „..1,41,11,,,, . 'N.. 416,44N-..., z �+ 14111 . It yr \ ) \ IlL { v \ r ► l r>« I T4110 i 9 Northern end of case B _ #!z .' 11 1 i / . Ill 'at' .1. N Northern end of case C 1 1y to ---- .,. h 1 i 0 z z v-'' ''\,,,. Northern end of case D 4 t • McCrory•_5km 1 ,7:,, gi. • Shallowest t • Middle 1 o • Deepest z Z i.,-- i 1 • 2008 Slab Contours \,) I itt 0 50 100 200 300 40' Kilometers z t Air - 6 1 v 128 W 126'W 124"W 122 W G RQ LOCATION OF SURFACE TRACES FOR UP-DIP EDGE & THREE DOWN-DIP EDGE OPTIONS USED IN 2014 NSHMS (CHEN ET.AL 2014) APR.2019 JOB NO. 5970-K FIG. 4C