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C o CEO DESIGNV RECEIVED SEP 21 2016 CITY OF TIGARD • •!NG DIVISION A REPORT OF GEOTECHNICAL ENGINEERING SERVICES 72"d Avenue and SW Dartmouth Street Site Parcels I and II Tigard, Oregon For Basecamp I, LLC March 2, 2016 GeoDesign Project: Basecamp-1-02 CDESIGN) a March 2, 2016 Basecamp I, LLC Attention: Mr. Brian Bennett Report of Geotechnical Engineering Services 72"d Avenue and SW Dartmouth Street Site Parcels I and II Tigard, Oregon GeoDesign Project: Basecamp-1-02 GeoDesign, Inc. is pleased to submit our geotechnical engineering services report for the site located southwest of SW 72nd Avenue and SW Dartmouth Street in Tigard, Oregon. Our services for this project were conducted in accordance with our proposal dated January 27, 2016. We appreciate the opportunity to be of service to you. Please call if you have questions regarding this report. Sincerely, GeoDesign, Inc. Scott V. Mills, P.E., G.E. Principal Engineer cc: Mr.Jeff Ganz, Lease Crutcher Lewis (via email only) Mr. Chuck Gregory, AKS Engineering (via email only) Mr. Scott Harris,JRJ Architects, LLC (via email only) TCM:SMD:kt Attachments One copy submitted(via email only) Document ID: Basecamp-1-02-030216-geor.docx ©2016 GeoDesign, Inc. All rights reserved. 15575 SW Sequoia Pkwy,Suite 100 I Portland,OR 97224 1503.968.8787 www.geodesigninc.com TABLE OF CONTENTS PAGE NO. 1.0 INTRODUCTION 1 2.0 PURPOSE AND SCOPE 1 3.0 SITE CONDITIONS 2 3.1 Surface Conditions 2 3.2 Subsurface Conditions 2 4.0 CONCLUSIONS 3 5.0 SITE DEVELOPMENT RECOMMENDATIONS 4 5.1 Site Preparation 4 5.2 Construction Considerations 5 5.3 Trench Excavations 5 5.4 Temporary and Permanent Slopes 6 5.5 Erosion Control 6 5.6 Structural Fill 7 6.0 FOUNDATION SUPPORT RECOMMENDATIONS 9 6.1 Spread Footings 9 7.0 SLABS-ON-GRADE 10 8.0 PERMANENT RETAINING STRUCTURES 1 1 8.1 Wall Design Parameters 1 1 8.2 Wall Drainage and Backfill 1 1 9.0 DRAINAGE CONSIDERATIONS 12 9.1 Site Drainage 12 9.2 Foundation Drains 12 10.0 SEISMIC DESIGN CRITERIA 12 11.0 PAVEMENT RECOMMENDATIONS 13 11.1 Pavement Design 13 11.2 Conventional Pavement Material Requirements 13 12.0 OBSERVATION OF CONSTRUCTION 13 13.0 LIMITATIONS 14 FIGURES Vicinity Map Figure 1 Site Plan Figure 2 Surcharge-Induced Lateral Earth Pressures Figure 3 APPENDICES Appendix A Field Explorations A-1 Laboratory Testing A-2 Exploration Key Table A-1 Soil Classification System Table A-2 Test Pit Logs Figures A-1 -A-8 Atterberg Limits Test Results Figure A-9 Summary of Laboratory Data Figure A-10 G EODESIGN= Basecamp-1-02:030216 TABLE OF CONTENTS PAGE NO. APPENDICES (continued) Appendix B Explorations on Nearby Site B-1 Site Plan and Exploration Logs ACRONYMS AND ABBREVIATIONS G EODESIGN= Basecamp-1-02:030216 1.0 INTRODUCTION GeoDesign, Inc. is pleased to submit this report of geotechnical engineering services for the site located southwest of SW 72,d Avenue and SW Dartmouth Street in Tigard, Oregon. The site is shown relative to surrounding physical features on Figure 1. The site currently consists of a vacant lot vegetated with grasses, bushes, and small trees. Development plans were preliminary at the time of our study, but will likely consist of a one-story medical facility at the northeastern portion of the site and associated paved parking, drive aisles, utilities, and landscaped areas. Structural loading information was not available at the time of this report; however, we have assumed maximum interior column loads will be less than 120 kips. We have assumed that floor loads will be less than 150 psf. Based on our discussions and information provided by Lease Crutcher Lewis, we understand that site cuts on the southeastern corner of the site may be up to 25 feet below existing site grades and site fills on the northwestern portion of the site will be on the order of 16 feet. GeoDesign is currently preparing and environmental report for the site and from a review of the historical aerial photographs we understand a farmstead and associated structures were located in the southwestern area of the site from at least 1953 through 1989. Acronyms and abbreviations used herein are defined at the end of this document. 2.0 PURPOSE AND SCOPE The purpose of our work was to explore site subsurface conditions and provide geotechnical engineering recommendations for use in design and construction of the proposed development. Our specific scope of work included the following: • Coordinated and managed the field investigation, including locating utilities, site access authorizations, access preparation, and scheduling of contractors and GeoDesign staff. • Reviewed readily available geotechnical and geologic information for the site area. • Explored subsurface conditions by excavating eight test pits (TP-1 through TP-8) to depths of up to 26 feet BGS using a moderately large, tracked excavator. Test pit excavations were backfilled upon completion. • Obtained geotechnical soil samples for laboratory testing and maintained a log of subsurface conditions. • Completed the following laboratory analyses on disturbed samples obtained from the explorations: • Fifteen moisture content determinations in general accordance with ASTM D 2216 • Two Atterberg limits tests in general accordance with ASTM D 4318 • Provided recommendations for site preparation, grading and drainage, compaction criteria for both on-site and imported material, fill type for imported material, procedures for use of on-site soil, and wet weather earthwork procedures. • Evaluated groundwater conditions at the site and provided general recommendations for dewatering during construction and subsurface drainage. G EODESIGN= 1 Basecamp-1-02:030216 • Provided recommendations for the use of on-site native and fill material for support of floor slabs and pavements. • Provided recommendations for shallow foundations, including recommendations for allowable bearing capacity, settlement, and lateral resistance. • Provided recommendations for use in the design of conventional retaining walls, including backfill and drainage requirements and lateral earth pressures. • Provided recommendations for construction of asphalt and concrete pavements for on-site access roads and parking areas, service access, and building aprons (including subbase, base course, and paving thickness). • Provided recommendations for seismic design factors in accordance with the procedures outlined in the 2012 IBC and the 2014 SOSSC. • Prepared this report that presents our findings, conclusions, and recommendations. 3.0 SITE CONDITIONS 3.1 SURFACE CONDITIONS The site consists of an L-shaped parcel located southwest of the intersection of SW Dartmouth Street and SW 72'Avenue in Tigard. Several small soil stockpiles are present near the middle of the site. The southeastern corner of the site is occupied by two vacant residences and the remainder of the site is vacant and heavily vegetated with grasses and includes areas of trees and bushes along the southern and middle portions of the site. A vegetated swale borders the north end of the site, beyond which is SW Dartmouth Street. The surrounding vicinity primarily consists of commercial, office, and single-family residential development. Site topography slopes downward from the southeast to northwest corner. Site elevations generally range from elevation 240 feet above MSL at the southwest corner to 185 feet above MSL at the northwestern corner. 3.2 SUBSURFACE CONDITIONS We explored subsurface conditions at the site by excavating eight test pit explorations (TP-1 through TP-8) to depths of up to 26 feet BGS using a moderately large, tracked excavator. In addition, we reviewed subsurface conditions from our previous 2005 geotechnical study for the development to the west, which included 17 test pit explorations to depths up to 1 5.5 feet BGS. The approximate exploration locations for our current study are shown on Figure 2 and the exploration logs are presented in Appendix A. The site plan and exploration logs for our previous study at the adjacent site to the west are presented in Appendix B. The site is generally underlain by silt and clay to the maximum depth of our explorations. The following sections provide a brief description of the subsurface conditions encountered in the explorations. 3.2.1 Soil Based on results our recent explorations at the site and review of information for the adjacent site, subsurface conditions generally consist of medium stiff to very stiff silt with varying amounts of sand to the total depths explored of 26 feet BGS. Fill was encountered to a depth of 2 feet in test pit TP-8 located within the northwestern portion of the site. The fill consists of medium stiff silt with trace sand. A 3-inch-diameter red clay pipe was observed at a depth of G EO DESIGNS 2 Basecamp-1-02:030216 1.5 feet BGS within the fill. We encountered several cobbles in test pits TP-1 and TP-2 at depths of 5 to 16 feet BGS. In addition, one boulder up to 18 inches in diameter was encountered in test pit TP-2 at a depth of 10 feet BGS. Cobbles or boulders were not encountered in any other explorations completed across the site. A 2-to 5-inch thick root zone was observed in all explorations. 3.2.2 Groundwater Groundwater was not observed during our field investigation. Groundwater seepage was encountered in ten test pits at the adjacent site to the west. Perched groundwater may accumulate at shallower depths during the wet season or extended periods of precipitation, and groundwater conditions may also fluctuate in response to changes in surface topography and other factors not observed during this study. 4.0 CONCLUSIONS Based on the results of our subsurface explorations and engineering analyses, it is our opinion that the site can be developed as proposed. In our opinion, the following factors will have an impact on design and construction of the proposed facility: • The building can be established on shallow foundations bearing on the native silt or structural fill placed over undisturbed native soil. • Several small stockpiles are located near the middle of the site. The stockpiles may consist of or contain deleterious materials such as debris or strippings that need to be removed and disposed of or only used as fill in non-structural areas. • Two vacant residences are located in the southeast portion of the site and former structures associated with a farmstead were located in the southwestern portion of the site. Underground remnants of the existing and former structures, where encountered, will require demolition. • Site grading includes cuts in the southern portion of the site and fills of up to 16 feet in the northwest portion of the site. To limit post-construction settlement we recommend waiting at least four weeks after site filling is complete, unless survey data indicates settlement is complete prior to that, before the construction of structural elements in fill areas of the site. • The on-site soil is suitable for use as structural fill provided it is properly moisture conditioned. However, it will be difficult, if not impossible, to achieve adequate compaction of on-site soil during periods of wet weather. • The on-site soil will provide inadequate support for construction equipment during periods of persistent rainfall. Granular haul roads and working pads or cement amendment should be employed if earthwork will occur during the wet winter months. • We observed several cobbles in test pits TP-1 and TP-2 at depths of 5 to 16 feet BGS. In addition, one boulder up to 18 inches in diameter was encountered in test pit TP-2 at a depth of 10 feet BGS. Cobbles or boulders were not encountered in any other explorations completed across the site. When encountered, cobbles and especially boulders will result in difficult excavation conditions and may require special equipment and procedures for removal. G EODESIGN= 3 Basecamp-1-02:030216 The following sections present specific recommendations for use in design and construction of the proposed development. 5.0 SITE DEVELOPMENT RECOMMENDATIONS 5.1 SITE PREPARATION 5.1.1 Grubbing and Stripping The existing root zone should be stripped and removed from the site in all proposed building and pavement areas and for a 5-foot margin around such areas. Based on our explorations, the depth of stripping will be approximately 3 to 6 inches, although greater stripping depths will be required in the heavily forested areas and to remove localized zones of loose or organic soil. Greater stripping depths may be required to remove localized zones of loose or organic soil, and the actual stripping depth should be based on field observations at the time of construction. Stripped material should be transported off site for disposal or used in landscaped areas. 5.1.2 Demolition Buried and abandoned utilities, septic systems, and foundations associated with current and previous structures at the site may affect construction. Abandoned improvements encountered in areas of new improvements should be completely removed. Existing pipes may be grouted full if left in place. Excavations required for removal of utilities, septic systems, and foundations should be excavated to expose a firm subgrade before filling and their sides sloped at a minimum of 1 H:1 V to allow for uniform compaction at the edges of the excavations. All excavations resulting from removal of improvements and existing excavations at the site should be backfilled with compacted structural fill. Material generated during demolition of existing improvements should be transported off site for disposal or stockpiled in areas designated by the owner. In general, this material will not be suitable for re-use as engineered fill. However, asphalt, concrete, and base rock material may be crushed and recycled for use as general fill. Such recycled material should meet the specifications for imported granular material as described in the "Structural Fill" section of this report. 5.1.3 Subgrade Preparation and Evaluation Historical aerial photographs indicate the open areas of the site have been farmed; therefore, an approximately 12-inch-thick tilled zone should be anticipated for areas not vegetated with trees and older vegetation. If site cuts do not remove the tilled zone, we recommend removing or scarifying the stripped ground surface to the depth of the tilled zone within all building and paved fill areas prior to placing structural fill. The scarified soil should be compacted as recommended for structural fill. As discussed in the "Structural Fill" section of this report, the on-site silty material can be sensitive to small changes in moisture content and will be difficult, if not impossible, to compact adequately during wet weather. Accordingly, scarification and compaction of the subgrade will likely only be possible during extended dry periods and following moisture conditioning of the soil. Following stripping and prior to placing fill, pavement, or building improvements, the exposed subgrade should be evaluated by proof rolling. The subgrade should be proof rolled with a fully loaded dump truck or similar heavy, rubber-tired construction equipment to identify soft, loose, or unsuitable areas. A member of our geotechnical staff should G EO DESIG N= 4 Basecamp-1-02:030216 observe proof rolling to evaluate yielding of the ground surface. Soft or loose zones identified during proof rolling should be excavated and replaced with compacted structural fill. Areas that appear too wet or soft to support proof rolling equipment should be evaluated by probing and prepared in accordance with recommendations for wet weather construction provided in the "Construction Considerations" section of this report. 5.1.4 Test Pit Locations The test pit excavations were backfilled using the relatively minimal compactive effort of the excavator bucket; therefore, soft spots can be expected at these locations. We recommend that this relatively uncompacted soil be removed from the test pits to a depth of 3 feet below finished subgrade. If a test pit is located within 10 feet of a footing, we recommend full-depth removal of the uncompacted soil. The resulting excavation should be brought back to grade with structural fill. 5.2 CONSTRUCTION CONSIDERATIONS Fine-grained soil present on this site is easily disturbed during the wet season. If not carefully executed, site preparation, utility trench work, and roadway excavation can create extensive soft areas and significant repair costs can result. Earthwork planning should include considerations for minimizing subgrade disturbance. If construction occurs during the wet season, or if the moisture content of the surficial soil is more than a few percentage points above optimum, site stripping and cutting may need to be accomplished using track-mounted equipment, loading removed material into trucks supported on granular haul roads. The thickness of the granular material for haul roads and staging areas will depend on the amount and type of construction traffic and should be the responsibility of the contractor. Generally, a 12-to 18-inch-thick mat of granular material is sufficient for light staging areas and the basic building pad but is generally not expected to be adequate to support heavy equipment or truck traffic. The granular mat for haul roads and areas with repeated heavy construction traffic typically needs to be increased to between 18 to 24 inches. The actual thickness of haul roads and staging areas should be based on the contractor's approach to site development and the amount and type of construction traffic. The material used to construct haul roads and staging areas should also be selected by the contractor. We recommend a separation geotextile meeting the requirements in the "Structural Fill" section of this report be placed as a barrier between silty subgrade material and imported granular material in areas of repeated construction traffic. 5.3 TRENCH EXCAVATIONS 5.3.1 Trench Cuts and Shoring Cobbles were observed in test pits TP-1 and TP-2 and one boulder was encountered in test pit TP-2. If encountered, cobbles and boulders will result in difficult trench excavations and wider trenches, increasing the amount of backfill material required. Trench cuts should stand vertical to a depth of approximately 4 feet, provided groundwater seepage does not occur. Open excavation techniques may be used to excavate trenches with G EODESIGNz 5 Basecamp-1-02:030216 depths between 4 and 10 feet BGS, provided the walls of the excavation are cut at a slope of 1.5H:1 V and groundwater seepage is not present. Sloughing and caving will likely occur if the excavation extends below the groundwater table or if seepage is present. The walls of the trench should be flattened or braced for stability and the area dewatered if seepage is encountered. Use of a trench box or other approved temporary shoring is recommended for cuts below the water table. If shoring is used, we recommend that the type and design of the shoring system be the responsibility of the contractor, who is in the best position to choose a system that fits the overall plan of operation. 5.3.2 Dewatering We anticipate that a sump located within the trench excavation will likely be sufficient to remove the accumulated water, depending on the amount and persistence of water seepage and the length of time the trench is left open. Flow rates for dewatering are likely to vary depending on location, soil type, and the season during which the excavation occurs. The dewatering systems should be capable of adapting to variable flows. If groundwater and fine-grained soil are present in the base of the utility trench excavation, we recommend over-excavating the trench by 12 to 18 inches and placing trench stabilization material in the base. 5.3.3 Safety All excavations should be made in accordance with applicable OSHA and state regulations. While we have described certain approaches to utility trench excavations in the foregoing discussion, the contractor should be responsible for selecting the excavation and dewatering methods, monitoring the trench excavations for safety, and providing shoring as required to protect personnel and adjacent areas. 5.4 TEMPORARY AND PERMANENT SLOPES Slopes less than 15 feet high should be no steeper than 1.5H:1 V. If slopes greater than 15 feet high are required, GeoDesign should be contacted to make additional recommendations. All temporary cut slopes should be protected from erosion by covering them during wet weather. If groundwater seepage is encountered or excessive sloughing or instability is observed, the slope should be flattened or the cut supported by shoring. Permanent cut and fill slopes should be graded at an inclination of 2H:1 V or flatter. Fill slopes should be overbuilt by at least 18 inches and then trimmed back to the appropriate grade. Slopes should be planted with appropriate vegetation to provided protection against erosion as soon as possible after grading. Surface water runoff should be collected and directed away from slopes to prevent water from running down the face of the slope. Footings, buildings, access roads, and pavements should be located at least 5 feet horizontally from the slope face. 5.5 EROSION CONTROL The on-site soil is moderately susceptible to erosion. Consequently, we recommend that slopes be covered with an appropriate erosion control product if construction occurs during periods of wet weather. We recommend that all slope surfaces be planted as soon as practical to minimize erosion. Surface water runoff should be collected and directed away from slopes to prevent G EODESIGNz 6 Basecamp-1-02:030216 water from running down the slope face. Erosion control measures such as straw bales, sediment fences, and temporary detention and settling basins should be used in accordance with local and state ordinances. 5.6 STRUCTURAL FILL Structural fill includes fill beneath foundations, slabs, pavements, any other areas intended to support structures, or within the influence zones of structures. Structural fill should be free of organic matter and other deleterious material and, in general, should consist of particles no larger than 3 inches in diameter. Recommendations for suitable fill material are provided in the following sections. 5.6.1 On-Site Native Soil The on-site native soil will be suitable for use as structural fill only if it can be moisture conditioned. The on-site silty soil is sensitive to small changes in moisture content and may be difficult, if not impossible, to compact adequately during wet weather or when its moisture content is more than a few percentage points above optimum. Laboratory tests indicate that the moisture content of the native silt unit is significantly greater than the anticipated optimum moisture content required for satisfactory compaction. Therefore, this soil may require extensive drying if it is used as structural fill. We recommend using imported granular material for structural fill if the moisture content of the on-site soil cannot be reduced. Native soil should be placed in lifts with a maximum uncompacted thickness of 8 inches and compacted to not less than 92 percent of the maximum dry density, as determined by ASTM D 1557. 5.6.2 Imported Granular Material Imported granular material should be pit- or quarry-run rock, crushed rock, or crushed gravel and sand that is fairly well graded between coarse and fine and has less than 5 percent by dry weight passing the U.S. Standard No. 200 Sieve. All granular material must be durable such that there is no degradation of the material during and after installation as structural fill. The percentage of fines can be increased to 12 percent if the fill is placed during dry weather and provided the fill material is moisture conditioned, as necessary, for proper compaction. The material should be placed in lifts with a maximum uncompacted thickness of 12 inches and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D 1557. During the wet season or when wet subgrade conditions exist, the initial lift should have a maximum thickness of 15 inches and should be compacted with a smooth-drum roller without the use of vibratory action. 5.6.3 Base Rock Imported durable granular material placed beneath building floor slabs and pavements should be clean crushed rock or crushed gravel and sand that is fairly well graded between coarse and fine. The granular material should have a maximum particle size of 1/2 inches, have less than 5 percent by dry weight passing the U.S. Standard No. 200 Sieve, and have at least two mechanically fractured surfaces. The imported base rock should be placed in one lift and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D 1557. G EODESIGN= 7 Basecamp-1-02:030216 5.6.4 Recycled Concrete Recycled concrete can be used for structural fill provided the concrete is processed to a relatively well-graded material with maximum particle size of 3 inches. This material can be used as trench backfill and general structural fill if it meets the requirements for imported granular material, which would require a smaller maximum particle size. The material should be placed in lifts with a maximum uncompacted thickness of 12 inches and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D 1557. 5.6.5 Trench Backfill Trench backfill for the utility pipe base and pipe zone should consist of durable well-graded granular material containing no organic or other deleterious material, have a maximum particle size of 3/ inch, and have less than 8 percent by dry weight passing the U.S. Standard No. 200 Sieve. Backfill for the pipe base and to the springline of the pipe should be placed in maximum 12-inch- thick lifts and compacted to not less than 90 percent of the maximum dry density, as determined by ASTM D 1557, or as recommended by the pipe manufacturer. Backfill above the springline of the pipe should be placed in maximum 12-inch-thick lifts and compacted to not less than 92 percent of the maximum dry density, as determined by ASTM D 1557. Trench backfill located within 2 feet of finish subgrade elevation should be placed in maximum 12-inch-thick lifts and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D 1557. 5.6.6 Stabilization Material If groundwater is present at the base of utility excavations, we recommend placing trench stabilization material at the base of the excavation consisting of at least 2 feet of well-graded gravel, crushed gravel, or crushed rock with a minimum particle size of 4 inches and less than 5 percent by dry weight passing the U.S. Standard No. 4 Sieve. The material should be free of organic matter and other deleterious material and should be placed in one lift and compacted until "well keyed." 5.6.7 Soil Amendment with Cement As an alternative to the use of imported granular material for wet weather structural fill, an experienced contractor may be able to amend the on-site silt and clay soil with portland cement or with limekiln dust and portland cement to obtain suitable support properties. Successful use of soil amendment depends on the use of correct mixing techniques, soil moisture content, and amendment quantities. Removal of oversized material may be required in some areas to prevent damage to the tilling equipment required for cement amendment. Amendment of the existing gravel surfacing material is not recommended. Specific recommendations for soil amending can be provided based on exposed site conditions, if necessary. However, for preliminary design purposes, we recommend a target strength for cement-amended soils of 80 psi. The amount of cement used to achieve this target generally varies with moisture content and soil type. It is difficult to predict field performance of soil to cement amendment due to variability in soil response, and we recommend laboratory testing to confirm expectations. Generally, 4 percent cement by weight of dry soil can be used when the G EO DESIGN= 8 Basecamp-1-02:030216 soil moisture content does not exceed approximately 20 percent. If the soil moisture content is in the range of 25 to 35 percent, 5 to 7 percent by weight of dry soil is recommended. The amount of cement added to the soil may need to be adjusted based on field observations and performance. Moreover, depending on the time of year and moisture content levels during amendment, water may need to be applied during tilling to appropriately condition the soil moisture content. Portland cement-amended soil is hard and has low permeability; therefore, this soil does not drain well, nor is it suitable for planting. Future planted areas should not be cement amended, if practical, or accommodations should be planned for drainage and planting. 5.6.8 Drain Rock Drain rock should consist of open-graded, angular granular material with a maximum particle size of 2 inches. The material should be free of roots, organic matter, and other unsuitable material and have less than 2 percent by dry weight passing the U.S. Standard No. 200 Sieve (washed analysis). 5.6.9 Geotextile Fabric 5.6.9.1 Separate Geotextile Fabric A separation geotextile fabric can be placed as a barrier between silty subgrade and granular material in staging areas, haul road areas, or in areas of repeated construction traffic. The subgrade geotextile should meet the requirements in OSSC 02320 (Geosynthetics) for subgrade geotextiles and be installed in conformance with OSSC 00350 (Geosynthetic Installation). 5.6.9.2 Drainage Geotextile Fabric Drain rock, and other granular material used for subsurface drains, should be wrapped in a geotextile fabric that meets the specifications provided in OSSC 00350 (Geosynthetic Installation) and OSSC 02320 (Geosynthetics) for drainage geotextiles and installed in conformance with OSSC 00350 (Geosynthetic Installation). 6.0 FOUNDATION SUPPORT RECOMMENDATIONS The planned structure may be supported by continuous wall and isolated column footings founded on the underlying undisturbed soil or on structural fill overlying firm native soil. We recommend waiting at least four weeks after site filling is complete unless survey data indicates settlement is complete prior to that before the construction of structural elements, including foundations in fill areas of the site. Our recommendations for use in foundation design and construction are provided in the following sections. 6.1 SPREAD FOOTINGS 6.1.1 Bearing Capacity The proposed structure can be supported on conventional spread footings bearing on firm, undisturbed native soil or on structural fill underlain by firm, undisturbed native soil. Undocumented fill, if encountered, should be removed from footing subgrade and backfilled with structural fill. The structural fill should extend a minimum of 6 inches beyond the footing perimeter for every foot excavated below the base grade of the footings. Due to the potential G EODESIGN= 9 Basecamp-1-02:030216 undocumented fill at the site, we recommend that we be retained to observe the footing subgrades and replacement of undocumented fill with structural fill, if required. We recommend that footings be sized based on an allowable bearing pressure of 2,500 psf. This is a net bearing pressure; the weight of the footing and overlying backfill can be ignored in calculating footing sizes. The recommended allowable bearing pressure applies to the total of dead plus long-term live loads and may be increased by 50 percent for short-term loads, such as those resulting from wind or seismic forces. Continuous wall and spread footings should be at least 16 inches wide. The bottom of exterior footings should be at least 18 inches below the lowest adjacent final grade. The bottom of interior footings should be placed at least 12 inches below the base of the floor slab. Total post-construction settlement is expected to be less than 1 inch. Differential settlement is expected to be less than Y2 inch. 6.1.2 Lateral Resistance Lateral loads on footings can be resisted by passive earth pressure on the sides of the footings and by friction on the base of the footings. The available passive earth pressure for footings confined by native soil and structural fill is 350 pcf. Adjacent floor slabs, pavements, or the upper 12-inch depth of adjacent, unpaved areas should not be considered when calculating passive resistance. A coefficient of friction equal to 0.35 may be used when calculating resistance to sliding on the native soil. A coefficient of friction equal to 0.45 may be used for footings founded on granular structural fill. 7.0 SLABS-ON-GRADE A minimum 6-inch-thick layer of base rock should be placed and compacted over the prepared subgrade to assist as a capillary break. The base rock should be crushed rock or crushed gravel and sand meeting the requirements outlined in the "Structural Fill" section of this report. The imported granular material should be placed in one lift and compacted to not less than 95 percent of the maximum dry density, as determined by ASTM D 1557. A subgrade modulus of 120 pci can be used to design the floor slab. Floor slab base rock should be replaced if it becomes contaminated with excessive fines (greater than 5 percent by dry weight passing the U.S. Standard No. 200 Sieve). Vapor barriers are often required by flooring manufacturers to protect flooring and flooring adhesives. Many flooring manufacturers will warrant their product only if a vapor barrier is installed according to their recommendations. Selection and design of an appropriate vapor barrier(if needed) should be based on discussions among members of the design team. We can provide additional information to assist you with your decision. G EODESIGN= 10 Basecamp-1-02:030216 8.0 PERMANENT RETAINING STRUCTURES 8.1 WALL DESIGN PARAMETERS Retaining structures free to rotate slightly around the base should be designed for active earth pressures using an equivalent fluid unit pressure of 35 pcf. If retaining walls are restrained against rotation during backfilling, they should be designed for an at-rest earth pressure of 55 pcf. This value is based on the assumption that (1) retained soil has a slope flatter than 4H:1 V, (2) the backfill is drained, and (3) the wall is less than 15 feet in height. Seismic lateral forces can be calculated using a dynamic force equal to 7H2 pounds per linear foot of wall, where H is the wall height. The seismic force should be applied as a distributed load with the centroid located at 0.6H from the wall base. Footings for retaining walls should be designed as recommended for shallow foundations. Lateral pressures induced by surcharge loads can be computed using the methods presented on Figure 3. 8.2 WALL DRAINAGE AND BACKFILL The above design parameters have been provided assuming that drains will be installed behind the walls to prevent buildup of hydrostatic pressures. If a drainage system is not installed, then our office should be contacted for revised design forces. Backfill material placed behind retaining walls and extending a horizontal distance of Y2H (where H is the height of the retaining wall) should consist of imported granular material. Alternatively, the native soil can be used as backfill material provided a minimum 2-foot-wide column of angular drain rock wrapped in a drainage geotextile is placed against the wall and the native soil can be adequately moisture conditioned for compaction. The drain rock column should extend from the perforated drainpipe or foundation drains to within approximately 1 foot of the ground surface. Perforated collector pipes should be placed at the base of the granular backfill behind the walls. The pipe should be embedded in a minimum 2-foot-wide zone of angular drain rock wrapped in a drainage geotextile fabric. The collector pipes should discharge at an appropriate location away from the base of the wall. Unless measures are taken to prevent backflow into the drainage system of the wall, the discharge pipe should not be tied directly into stormwater drain systems. Backfill should be placed and compacted as recommended for structural fill, with the exception of backfill placed immediately adjacent to walls. Backfill adjacent to walls should be compacted to a lesser standard to reduce the potential for compaction-induced earth pressures on the walls. Backfill located within a horizontal distance of 3 feet from the retaining walls should be compacted to approximately 90 percent of the maximum dry density, as determined by ASTM D 1557. Backfill placed within 3 feet of the wall should be compacted in lifts less than 6 inches thick using hand-operated tamping equipment (such as a jumping jack or vibratory plate compactor). If flatwork (such as slabs, sidewalk, or pavement) will be placed adjacent to the wall, we recommend that the upper 2 feet of fill be compacted to 95 percent of the maximum dry density, as determined by ASTM D 1557. G EODESIGN? 11 Basecamp-1-02:030216 Settlement of up to 1 percent of the wall height commonly occurs immediately adjacent to the wall as the wall rotates and develops active lateral earth pressures. Consequently, we recommend that construction of flatwork adjacent to retaining walls be postponed at least four weeks after construction, unless survey data indicates that settlement is complete prior to that time. 9.0 DRAINAGE CONSIDERATIONS 9.1 SITE DRAINAGE We recommend that roof drains be connected to a tightline leading to storm drain facilities. Pavement surfaces and open space areas should be sloped such that surface water runoff is collected and routed to suitable discharge points. We also recommend that ground surfaces adjacent to buildings be sloped to facilitate positive drainage away from the buildings. 9.2 FOUNDATION DRAINS We recommend using foundation drains around the perimeter of building areas where floor slabs are constructed more than 2 feet below existing grades. The foundation drains should be installed at least 2 feet below the finished floor grade, constructed at a minimum slope of approximately Y2 percent, and routed to a suitable discharge (e.g., connected to the storm drain system). The foundation drains should consist of 4-inch-diameter, perforated drainpipe embedded in a minimum 2-foot-wide zone of drain rock wrapped in a drainage geotextile. Foundation drains for embedded walls should be constructed as recommended in the "Permanent Retaining Structures" section of this report. 10.0 SEISMIC DESIGN CRITERIA Seismic design is prescribed by the 2014 SOSSC and the 2012 IBC. Table 1 presents the site design parameters prescribed by the 2012 IBC for the site. Table 1. Seismic Design Parameters Parameter Short Period 1 Second Period (T==0.2 second) (T, = 1.0 second) MCE Spectral Acceleration, S S = 0.979 g S = 0.423 g Site Class D Site Coefficient, F Fa= 1.108 F = 1 .577 Adjusted Spectral Acceleration, SM SMS = 1 .085 g SM1 = 0.668 g Design Spectral Response Acceleration Parameters SSDS= 0.724 g SDI = 0.445 g D G EO DESIG N= 12 Basecamp-1-02:030216 Liquefaction settlement is the result of seismically induced densification and subsequent ground settlement of loose sand and silty sand below the groundwater table. Based on the findings of our subsurface exploration, it is our opinion that there is a low risk of liquefaction and liquefaction-related hazards at the site. 11.0 PAVEMENT RECOMMENDATIONS 11.1 PAVEMENT DESIGN Our pavement recommendations are based on a minimum California Bearing Ratio value of 3 and a design life of 20 years. We do not have specific information on the frequency and type of vehicles that will use the area; however, we have assumed that post-construction traffic conditions will consist of no more than five heavy trucks per day. We recommend a pavement section consisting of a minimum of 3.0 inches of AC pavement underlain by a minimum of 10.0 inches of aggregate base. For areas subjected to passenger car traffic only, we recommend a pavement section consisting of a minimum of 2.5 inches of AC pavement underlain by a minimum of 8.0 inches of aggregate base. All thicknesses are intended to be the minimum acceptable. The design of the recommended pavement section is based on the assumption that construction will be completed during an extended period of dry weather. Wet weather construction could require an increased thickness of aggregate base. We can provide additional recommendations in a separate memorandum if pavement design is required for public roadways. If the subgrade is stabilized with portland cement, a section consisting of 2.5 inches of AC over 4.0 inches of aggregate base should be appropriate in passenger car traffic areas and 3.0 inches of inches of AC over 4.0 inches of aggregate base in the site access and truck traffic areas. These sections are based on a minimum unconfined compressive strength of 80 psi and a mixing depth of at least 12 inches below the crushed rock base. 11.2 CONVENTIONAL PAVEMENT MATERIAL REQUIREMENTS The AC should be Level 2, %2-inch, dense ACP as described in OSSC 00744 (Asphalt Concrete Pavement) and be compacted to 91 percent of the specific gravity of the mix, as determined by ASTM D 2041. Minimum lift thickness for Y2-inch, dense ACP is 2.0 inches. Asphalt binder should be performance graded and conform to PG 64-22. 12.0 OBSERVATION OF CONSTRUCTION Satisfactory earthwork and foundation performance depends to a large degree on the quality of construction. Subsurface conditions observed during construction should be compared with those encountered during the subsurface explorations. Recognition of changed conditions often requires experience; therefore, qualified personnel should visit the site with sufficient frequency to detect whether subsurface conditions change significantly from those anticipated. In addition, sufficient observation of the contractor's activities is a key part of determining that the work is completed in accordance with the construction drawings and specifications. G EODESIGN= 13 Basecamp-1-02:030216 A 13.0 LIMITATIONS We have prepared this report for use by Basecamp I, LLC and members of their design and construction teams for the proposed project. The data and report can be used for estimating purposes, but our report, conclusions, and interpretations should not be construed as a warranty of the subsurface conditions and are not applicable to other sites. Soil explorations indicate soil conditions only at specific locations and only to the depths penetrated. The soil explorations do not necessarily reflect soil strata or water level variations that may exist between exploration locations. If subsurface conditions differing from those described are noted during the course of excavation and construction, re-evaluation will be necessary. In addition, if design changes are made, we should be retained to review our conclusions and recommendations and to provide a written evaluation or modification. The scope of our services does not include services related to construction safety precautions, and our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in our report for consideration in design. Within the limitations of scope, schedule, and budget, our services have been executed in accordance with the generally accepted practices in this area at the time this report was prepared. No warranty or other conditions, express or implied, should be understood. ♦ ♦ ♦ We appreciate the opportunity to be of continued service to you. Please call if you have questions concerning this report or if we can provide additional services. Sincerely, GeoDesign, Inc. C �xsO PROFFs fie- .&G NFF,Q oy Tacia C. Miller, P.E., G.E. ' 6311E Senior Associate Engineer oFEGON 71 oz. eh 14, 2 �(t. q \M wN D awn M. Dimke, P.E., G.E. Principal Engineer EXPIRES: 12/31/17 Scott V. Mills, P.E., G.E. Principal Engineer G EODESIGN= 14 Basecamp-1-02:030216 n -11 c 73 m Vi • - --„- ----------___ 7 s 1 , '.. 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Z=nH Z=TnH .41110111111.— 1 W 1 H IW H rff H IllW IS ah iir ah IR ah 4\ FOR m<0.4= \�\\� FOR m<0.4= \\\� ah=2L (p-SIN/3 COS 2a) \�\,\ a _Q p 0.28 r? /\\\%\ a _ Q L 0.2 n j/\\\j\ 3.14 r��//�///\//\/\\\� h H 2 (0.16+r� � i//%//��///\\�//\ h H (0.16+r ./>//>\,,,\\//j (p IN RADIANS) FOR m>0.4= FOR m>0.4= a _1a 1.77rr2 r? a QL 1.28m2n h H2 (m2+n-)3 h =H (m +r�)2 LINE LOAD PARALLEL TO WALL STRIP LOAD PARALLEL TO WALL X=mH ah =°h COSz(1.1�) NOTES: l , 1. THESE GUIDELINES APPLY TO RIGID WALLS WITH POISSON'S a RATIO ASSUMED TO BE 0.5 FOR BACKFILL MATERIALS. DISTRIBUTION OF HORIZONTAL PRESSURES 2. LATERAL PRESSURES FROM ANY COMBINATION OF ABOVE LOADS MAY BE DETERMINED BY THE PRINCIPLE OF VERTICAL POINT LOAD SUPERPOSITION. 3. VALUES IN THIS FIGURE ARE UNFACTORED. G EODESIGN= BAS ECAMP-1-02 SITE PLAN 15575 SW Sequoia Parkway-Suite 700 72ND AVENUE AND SW DARTMOUTH STREET SITE Portland OR97224 MARCH 2016 FIGURE 3 Off 503.968.8787 Fax 503.968.3068 TIGARD, OR m Z v_ X APPENDIX A FIELD EXPLORATIONS GENERAL We explored subsurface conditions at the site by excavating eight test pits (TP-1 through TP-8) to depths of up to 26 feet BGS across the site at locations designated by the design and construction team. Services were provided by Dan J. Fischer Excavating, Inc. of Forest Grove, Oregon. The test pits were excavated utilizing a John Deere 120D excavator on February 8, 2016. The explorations were completed at the approximate locations shown on Figure 2. The locations of the explorations were determined in the field by pacing from site features. This information should be considered accurate to the degree implied by the methods used. A member of our geotechnical staff observed the explorations. Exploration logs are presented in this appendix. SOIL SAMPLING We obtained representative samples of the various soil encountered in the test pit explorations for geotechnical laboratory testing. Representative grab samples of the soil observed in the test pits were obtained from the walls and/or base of the test pits using the excavator bucket. Sampling intervals are shown on the exploration logs. SOIL CLASSIFICATION The soil samples were classified in accordance with the "Exploration Key" (Table A-1) and "Soil Classification System" (Table A-2), which are presented in this appendix. The logs indicate the depths at which the soils or their characteristics change, although the change could be gradual. If the change occurred between sample locations, the depth was interpreted. Classifications shown on the exploration logs. LABORATORY TESTING CLASSIFICATION The soil samples were classified in the laboratory to confirm field classifications. The laboratory classifications are shown on the exploration logs if those classifications differed from the field classifications. MOISTURE CONTENT We tested the natural moisture content of selected soil samples in general accordance with ASTM D 2216. The natural moisture content is a ratio of the weight of the water to the dry weight of soil in a test sample and is expressed as a percentage. The test results are presented in this appendix. ATTERBERG LIMITS The plastic limit and liquid limit (Atterberg limits) of selected soil samples were determined in accordance with ASTM D 4318. The Atterberg limits were determined to aid in the classification of the soil. The test results are presented in this appendix. G EODESIGNz A-1 Basecamp-1-02:030216 , SYMBOL SAMPLING DESCRIPTION E Location of sample obtained in general accordance with ASTM D 1586 Standard Penetration Test with recovery I Location of sample obtained using thin-wall Shelby tube or Geoprobe® sampler in general accordance with ASTM D 1587 with recovery Location of sample obtained using Dames & Moore sampler and 300-pound hammer or pushed with recovery I Location of sample obtained using Dames & Moore and 140-pound hammer or pushed with recovery I Location of sample obtained using 3-inch-O.D. California split-spoon sampler and 140-pound hammer NLocation of grab sample Graphic Log of Soil and Rock Types :`: 'r Observed contact between soil or Rock coring interval s�; rock units(at depth indicated) SZ Water level during drilling Inferred contact between soil or rock units(at approximate depths indicated) Y Water level taken on date shown -: —- .t: -o y GEOTECHNICAL TESTING EXPLANATIONS ATT Atterberg Limits PP Pocket Penetrometer CBR California Bearing Ratio P200 Percent Passing U.S. Standard No. 200 CON Consolidation Sieve DD Dry Density RES Resilient Modulus DS Direct Shear SIEV Sieve Gradation HYD Hydrometer Gradation TOR Torvane MC Moisture Content UC Unconfined Compressive Strength MD Moisture-Density Relationship VS Vane Shear OC Organic Content kPa Kilopascal P Pushed Sample ENVIRONMENTAL TESTING EXPLANATIONS CA Sample Submitted for Chemical Analysis ND Not Detected P Pushed Sample NS No Visible Sheen PID Photoionization Detector Headspace SS Slight Sheen Analysis MS Moderate Sheen ppm Parts per Million HS Heavy Sheen G EODESIGNu. EXPLORATION KEY TABLE A-1 15575 SW Sequoia Parkway-Suite 100 Portland OR 97224 Off 503.968.8787 Fax 503.968.3068 RELATIVE DENSITY- 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 T 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 PRIMARY SOIL DIVISIONS GROUP SYMBOL GROUP NAME CLEAN GRAVELS GW or GP GRAVEL GRAVEL (< 5%fines) than 50%of GRAVEL WITH FINES GW-GM or GP-GM GRAVEL with silt (moree coharaction (z 5%and 5 12%fines) GW-GC or GP-GC GRAVEL with clay COARSE-GRAINED retained on GRAVELS WITH FINES GM silty GRAVEL SOILS No. 4 sieve) (> 12%fines) GC clayey GRAVEL GC-GM silty, clayey GRAVEL (more than 50% CLEAN SANDS retained on SAND (<5%fines) SW or SP SAND No. 200 sieve) or more of SANDS WITH FINES SW-SM or SP-SM SAND with silt coarse (50%o morion (z 5%and_< 12%fines) SW-SC or SP-SC SAND with clay passing SANDS WITH FINES SM silty SAND No. 4 sieve) SC clayey SAND (> 12%fines) SC-SM silty, clayey SAND ML SILT FINE-GRAINED CL CLAY SOILS Liquid limit less than 50 CL-ML silty CLAY (50%or more SILT AND CLAY OL ORGANIC SILT or ORGANIC CLAY passing Liquid limit 50 or MH SILT No. 200 sieve) greater CH CLAY OH ORGANIC SILT or ORGANIC CLAY HIGHLY ORGANIC SOILS PT PEAT MOISTURE ADDITIONAL CONSTITUENTS CLASSIFICATION Secondary granular components or other materials Term Field Test such as organics, man-made debris,etc. Silt and Clay In: Sand and Gravel In: very low moisture, Percent Fine-Grained Coarse- Percent Fine-Grained Coarse- dry dry to touch Soils Grained Soils Soils Grained Soils moist damp,without < 5 trace trace < 5 trace trace visible moisture 5 - 12 minor with 5 - 15 minor minor wet visible free water, > 12 some silty/clayey 15 - 30 with with usually saturated > 30 sandy/gravelly Indicate% G EoDESIGN= SOIL CLASSIFICATION SYSTEM TABLE A-2 15575 SW Sequoia Parkway-Suite 100 Portland OR 97224 Off 503.968 8787 Fax 503.968 3068 • v Z O om u w DEPTH <o- H •MOISTURE MATERIAL DESCRIPTION w COMMENTS FEET J p H < CONTENT% L.1 225.0 0 50 100 —0.0 Stiff, brown SILT(ML), trace sand and organics (fine roots); moist (2-inch-thick root zone). 2.5— without organics at 4.0 feet 5.0— 7.5— ATT • LL=NP PL=NP 10.0— cobble at 10.5 feet 12.5— • Excavator cut benching to dig 15.0— deeper than 15.0 feet(2-foot bench). 17.5— _ very stiff, light brown with rust mottles, X • i- trace organics (charcoal) at 18.0 feet 20.0— o Excavator deepened bench to dig deeper than 22.0 feet. 22.5— a0 i- u z Wu 25.0 1 Exploration completed at a depth of 26.00 No groundwater observed to the 26.0 feet. depth explored. 27 5— No caving observed to the depth Latitude: 45.43216 explored. Longitude: -122.751561 (determined from smartphone with GPS application) • 30.0 m 0 50 100 w EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 - a w d EXCAVATION METHOD:excavator(see document text) G EODESIGNZu BASECAMP 1 02 TEST PIT TP-1 15575 SW Sequoia Parkway-Suite 100 v� Portland OR 97224 72ND AVENUE AND SW DARTMOUTH STREET SITE Off 503.968.8787 Fax 503.968.3068 MARCH 2016 FIGURE A-1 TIGARD,OR Z L.7 O= L w DEPTH u Q o_ •MOISTURE FEET MATERIAL DESCRIPTION J t < CONTENT%• COMMENTS im u —0.0 216.0 0 50 100 Medium stiff, brown SILT(ML), trace organics (roots); moist (3-inch-thick root zone). 2.5 • without organics at 4.0 feet Excavator comment: intermittent 5.0 cobbles from 5.0 feet to maximum stiff, light brown,with cobbles, trace organics (charcoal) at 5.0 feet • depth explored. 7.5 10.o boulder (18-inch diameter) at 10.0 feet 1 2.5 203.5 Stiff, light brown CLAY with cobbles 12.5 (CL), some silt, trace organics; moist. ATT • PL=35% PL= 1 5% 15.0 200.0 Exploration completed at a depth of 16.0 No groundwater observed to the 16.0 feet. depth explored. No caving observed to the depth _ 17.5 Latitude: 45.432107 explored. Longitude: -122.751992 F (determined from smartphone with GPS he application) V 20.0— \ 0 — z 22.5— Fc — 0 I— u z — 2, 25.0- 2 O 2 w u u ao ' a 27.5— H _ N 9 d — 7 U a 30.0 0 50 100 EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 - a rr w d EXCAVATION METHOD:excavator(see document text) ° G EODESIGNu BASECAMP-1-02 TEST PIT TP-2 u 15575 SW Sequoia Parkway-Suite 100 in Portland OR 97224 72ND AVENUE AND SW DARTMOUTH STREET SITE F FIGURE A-2 Off 503.968.8787 Fax 503.968.3068 MARCH 2016 TIGARD,OR Z 0 = u w DEPTH u <a •MOISTURE MATERIAL DESCRIPTION J o H N CONTENT% COMMENTS a FEET d w 0 50 100 —0.0 216.0 Medium stiff, brown SILT(ML), trace sand and organics (roots); moist (4- to 5-inch-thick root zone). 2.5- stiff, light brown, trace to some organics (roots) at 2.0 feet • without organics at 4.0 feet 5.0— 7.5— 10.0— 1 2.5— light brown with rust mottles, minor • organics (charcoal) at 13.0 feet 15.0— • 200.0 Exploration completed at a depth of 16.0 No groundwater observed to the 16.0 feet. depth explored. 17.5— No caving observed to the depth Latitude: 45.432275 explored. Longitude: -122.751668 F (determined from smartphone with GPS application) U 20.0— C z• 22.5— Fe a I- O — u z 2 25.0— w 0 W — u B o ri ▪ 27.5— 9 — D. — Q U Q 30.0 0 50 100 EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 0. rx EXCAVATION METHOD:excavator(see document text) G EODESIGNuZ BASECAMP 1 02 TEST PIT TP-3 15575 SW Sequoia Parkway-Suite 100 Lt, Portland OR 97224 72ND AVENUE AND SW DARTMOUTH STREET SITE Off 503.968.6787 Fax 503.968.3068 MARCH 2016 FIGURE A-3 TIGARD,OR Z 0 0= J DEPTH u Q a N d •MOISTURE MATERIAL DESCRIPTION w COMMENTS FEET o- w C w < CONTENT% F- ce w u 207.0 0 50 100 —0.0 Medium stiff, brown SILT(ML), minor organics (roots), trace sand; moist (3- ® • inch-thick root zone). 2.5— stiff, light brown at 2.0 feet • 5.0- 7.5— light brown with rust mottles at 9.0 feet 10.0— • 12.5- 194.0 Exploration completed at a depth of 13.0 No groundwater observed to the 13.0 feet. depth explored. No caving observed to the depth ls.o— Latitude: 45.432219 explored. Longitude: -122.752223 (determined from smartphone with GPS application) 17.5— I U • 20.0 Z 22.5— 0 0. U _ Z 25.0— LL, 0 0 w u a - ✓ _ ro 0 27.5— r O - U U u 30.0 0 50 100 EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 0. d EXCAVATION METHOD:excavator(see document text) u • G E O DES I G N? BASECAMP-1-02 TEST PIT TP-4 ▪ 15575 SW Sequoia Parkway-Suite 100 v7 Portland OR 97224 72ND AVENUE AND SW DARTMOUTH STREET SITE FW- Off 503.968.8787 Fax 503.968.3068 MARCH 2016 FIGURE A-4 TIGARD,OR Z • o O= U w DEPTH Q a a •MOISTURE FEET MATERIAL DESCRIPTION >w vi CONTENT% COMMENTS N W 195.0 0 50 100 —0.0 Medium stiff, brown SILT(ML), trace sand and organics (roots); moist (3- inch-thick root zone). 2.5— stiff, light brown at 2.0 feet without organics at 4.0 feet 5.0— light brown with rust mottles at 6.0 feet 188.0 5_ Exploration completed at a depth of 7.0 7.0 No groundwater observed to the feet. depth explored. No caving observed to the depth Latitude: 45.432178 explored. Longitude: -122.752674 10.0— (determined from smartphone with GPS application) 12.5— 15.0— 17.5— I– Y U 20.0— 7 LL _ 22.5— a. r1 – 1-3 F O – V _ z 25.0- 0 O w _ 6 U _ ao F.: 27.5— H _ O _ Q — 30.0 0 50 t00 w EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 a d EXCAVATION METHOD:excavator(see document text) U G EO DES G NZ BASECAMP-1-02 TEST PIT TP-5 ▪ 15575 SW Sequoia Parkway-Suite 100 47 Portland OR 97224 72ND AVENUE AND SW DARTMOUTH STREET SITE F Off 503.968.8787 Fax 503.968.3068 MARCH 2016 FIGURE A-5 TIGARD,OR o o= u J Z DEPTH = MATERIAL DESCRIPTION a,a H •g •MOISTURE COMMENTS FEET o- p H < CONTENT% w 200.0 0 50 100 —0.0 Medium stiff, brown-gray SILT(ML), trace sand and organics (roots); moist (3-inch-thick root zone). 2.5 stiff, light brown with rust mottles at 2.0 feet 5.0— 193.0 5— Exploration completed at a depth of 7.0 7.0 No groundwater observed to the feet. depth explored. No caving observed to the depth Latitude: 45.432699 explored. Longitude: -122.751573 oo— (determined from smartphone with GPS application) 12.5— 15.0- 17.5- 1- Y U D 20.0 Z 22.5— oC d L z u 25.0— w — 0 w u V _ 00 aE' 27.5— ✓ _ 9 – f U U 30.0 0 50 100 EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 a EXCAVATION METHOD:excavator(see document text) ° • G EODESIGNu BASECAMP-1-02 TEST PIT TP-6 ▪ 1 5575 SW Sequoia Parkway-Suite 100—PoOff 503.9P8 eland O 79R 7503.968.3068 224 72ND AVENUE AND SW DARTMOUTH STREET SITE MARCH 2016 FIGURE A-6 TIGARD,OR p z O 02 Lu Z DEPTH a MATERIAL DESCRIPTION >0 w Q •MOISTURE COMMENTS as J I— N w —0.0 193.0 0 50 100 Medium stiff, gray with rust mottled • SILT(ML), trace sand and organics (roots); moist (3-inch-thick root zone). 2.5— light brown with rust mottles at 3.0 feet 5.0 7.5— 18 5.0 Exploration completed at a depth of 8.0 8.0 No groundwater observed to the feet. depth explored. No caving observed to the depth Latitude: 45.432678 explored. lo.o— Longitude: -122.752369 (determined from smartphone with GPS application) 12.5- 15.0 17.5- 1— U 20.0— 0 o - z 22.5— a F- 0 z - �-� 25.0- 0 o 0 W — U s u cc; E' 27.5— 9 _ a U U Q 30.0 0 50 100 a EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 d cc a. EXCAVATION METHOD:excavator(see document text) o aJ ▪ G EODESIGN BASECAMP-1-02 TEST PIT TP-7 � ▪ 15575 SW Sequoia Parkway-Suite 100 �at Portland OR 97224 72ND AVENUE AND SW DARTMOUTH STREET SITE H Off 503.968.8787 Fax 503.968.3068 MARCH 2016 FIGURE A-7 TIGARD,OR Z 0 0= u w DEPTH u <ba •MOISTURE FEET a MATERIAL DESCRIPTION >w CONTENT% COMMENTS -i H w 186.0 0 50 100 —0.0 Medium stiff, gray with rust mottled SILT(ML), trace sand and organics (roots); moist (3-inch-thick root zone) - Red clay pipe(-3-inch diameter)at FILL. 184.0 1.5 feet. 2.5— Stiff, light brown with rust mottled SILT 2.0 (ML), trace sand; moist. 5.0— 7.5— blue, with sand (approximately 30%) at 8.0 feet 10.0— x • 174.0 1 2.5— Exploration completed at a depth of 12.0 No groundwater observed to the 12.0 feet. depth explored. No caving observed to the depth Latitude: 45.43259 explored. Longitude: -122.752943 15.0— (determined from smartphone with GPS _ _ application) 17.5— I- Y 20.0— Q _ 2 22.5— C d — F z u 25.0— w 2 w u d - u eo 0 27.5— H O U U 30.0 m 0 50 100 w EXCAVATED BY:Dan J.Fischer Excavating,Inc. LOGGED BY:AJF COMPLETED:02/08/16 - o a EXCAVATION METHOD:excavator(see document text) 119 u BASECAMP-1-02 TEST PIT TP-8 G EODESIGN 15575 SW Sequoia Parkway-Suite 100— ut Portland OR 97224 72ND AVENUE AND SW DARTMOUTH STREET SITE F FIGURE A-8 Off 503.968.8787 Fax 503.968.3068 MARCH 2016 TIGARD,OR 60 50 CH or OH "A" LINE X 40 W u 30 N CL or OL J a 20 m - 10 MH or OH CL ML ML or OL 0 0 10 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT KEY EXPLORATION SAMPLE DEPTH MOISTURE CONTENT LIQUID LIMIT PLASTIC LIMIT PLASTICITY INDEX NUMBER (FEET) (PERCENT) • TP-1 7.0 27 NP NP NP i- m TP-2 14.0 30 35 15 20 z 2 w w u d 0 w v7 m r- G EODESIGNZ BASECAMP-1-02 ATTERBERG LIMITS TEST RESULTS - w 15575 5W Sequoia Parkway-Suite 100 MARCH 2016 72ND AVENUE AND SW DARTMOUTH STREET SITE Portland OR 97224 FIGURE A-9 Q Off 503.968.8787 Fax 503.968.3068 TIGARD,OR SAMPLE INFORMATION SIEVE ATTERBERG LIMITS MOISTURE DRY EXPLORATION SAMPLE ELEVATION CONTENT DENSITY GRAVEL SAND P200 LIQUID PLASTIC PLASTICITY NUMBER DEPTH (FEET) (PERCENT) (PCF) (PERCENT) (PERCENT) (PERCENT) LIMIT LIMIT INDEX (FEET) TP-1 7.0 218.0 27 NP NP NP TP-1 14.0 211.0 26 TP-1 18.0 207.0 32 TP-1 25.0 200.0 28 TP-2 2.0 214.0 54 TP-2 5.0 211.0 28 TP-2 14.0 202.0 30 35 15 20 TP-3 3.0 213.0 30 TP-3 13.0 203.0 23 TP-3 15.0 201.0 21 TP-4 0.5 206.5 29 TP-4 3.0 204.0 29 TP-4 10.0 197.0 28 TP-7 1.0 192.0 20 TP-8 9.0 177.0 28 F- Y Z a I- 0 z 0 0 O w cc d. ut m (' Q V EODESIGN? BASECAMP-1-02 SUMMARY OF LABORATORY DATA 2 15575 SW Sequoia Parkway-Suite 100 72ND AVENUE AND SW DARTMOUTH STREET SITE Portland OR 97224 MARCH 2016 FIGURE A-10 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR m Z X APPENDIX B EXPLORATIONS ON NEARBY SITE We reviewed the geotechnical report for the investigation we conducted at the adjacent site to the west to evaluate subsurface conditions. The site plan and explorations logs from the report are presented in this appendix. G EODESIGN= B-1 Basecamp-1-02:030216 NM ® .= IM NM ! M NM MI Mill 1 NM I= MI N - -I Jun 09.2005•10 31 37 DWG Name PacTrust-111-01-5P•FIGURE-2.dwg Updated By cmp TAX LOT 101 Sip �gRT 007. PREVIOUS SITE EXPLORED BY GEODESIGN 0,40 j TAX LOT 100 TAX LOT 300 TP-14 I9 SITE"B" 1 I TP-7 r W ITP-1 6 TP-16 6 I I TP-8 A I SITE"A" j ! TP-6 6 TP-17 Fli I 'ItI TP136 i I Z 1 I EXPLANATION: I TP-9 6 TAX LOT 401 ' I 3 in 1 TP-2 6TP-1 5 y I TAX LOT 400 ! 1 ---- SITE BOUNDARY SITE"D" TP-5 9 TP-12 "9 I j TAX LOT 402 1 ( TP-1 % TEST PIT I TP-10 NI r----.........._ t ..... SITE"C" 1 I f N i TP-3 = TP 4 ji ', 0 200 400 L._ I i I 1 1 I ( FEET) -� TP-1 SW ' 1N HERMOS0 WA Y -•..J SITE PLAN BASED ON DRAWING PROVIDED BY pacific REALITY ASSOCIATES, LP G EODESIGN= PACT RUST-111-01 SITE PLAN 15575 SW Sequoia Parkway-Suite 100 Portland 00.9722 JUNE 2005 TRI-COUNTY RETAIL CENTER FIGURE 2 Off 503.968.8787 Fax 503.968.3068 TIGARD,OR A 0 S DEPTH u >= Z •MOISTURp/E I FEET d MATERIAL DESCRIPTION WIb- • N CONTENT /q COMMENTS u p w N I- TP-1 0.0 • • o 50 100 ..❖... Medium stiff, brown SILT with some : : gravel, trace sand and organics, and •_ .•.•.• occasional cobbles; moist(fill, 3-inch- ' •:•::.i. thick root zone). 2.5 ❖:• • :❖ becomes stiff at 3.0 feet �����• • • • Slow groundwater seepage I •••••• observed at 4.0 feet. 5.0 • ❖:•i ••••• becomes medium stiff with occasional $::: cobble-size pieces of asphalt debris at ® 0 ❖•:• 5. ... 0 feet • . . encountered piece of wire at 6.0 feet 7.5 :❖; Moderate caving observed from •••••• 7.5 to 10.0 feet. ❖•• •; Slow groundwater seepage ••• •O:•: observed from 8.0 to 8.5 feet. •• 10.0 •❖•:•i • ••••• I - Stiff, brown SILT with gray mottles and 110 trace clay; moist. PP PP= 1.75 tsf 12.5- Test pit completed at 12.0 feet. 1 z.o - 1 5.0- I TP-2 o 50 100 0 50 100 0.0 ......; Medium stiff, brown SILT with trace ::: gravel, clay, and fine sand; moist(fill, 4- I ••:: inch-thick root zone). 2.5 • AN o •'•'•'• becomes stiff at 3.0 feet •❖•• Iii 5.0 ❖••i o �.��� becomes dark brown at 5.0 feet I • • •••• with some fine to coarse gravel at 6.0 ••••, feet 7.5 •:.::: with occasional cobble-size asphalt Ei 0 :•••; I pieces from 6.0 to 9.0 feet ... ••••• .❖., 55 o *SSS 0 10.0 •.❖• o ••••i I •••• ••••••, I- 12.5 • :❖i "'• No groundwater seepage observed I Z;; �i Stiff, dark gray, clayey SILT; moist. ^ 13.0 9 Y Y ® to the depth explored. co Test pit completed at 13.5 feet. 13.5 No caving observed to the depth - explored. oCC 15.0- I .a 0 50 100 w aEXCAVATED BY:Western States Soil Conservator,Inc. LOGGED BY:SMD COMPLETED:05/27/05 C w o. EXCAVATION METHOD:trackhoe(see report text) a GEODESIGN� k PACTRUST-1 1 1-0 1 TEST PIT I W 1 S575 SW Sequoia Parkway-Suite 100 Porzlandgoal OR9722450. JUNE 2005 TRI-COUNTY RETAIL CENTER FIGURE A-1 Off 503.963.8797 Fax 503.968.306! TIGARD, OR I u = z J •MOISTURE I EH d MATERIAL DESCRIPTION' a. J W H g CONTENT% COMMENTS 0 I- vl L., TP-3 00 •• 0 so 100 ...❖. Medium stiff, brown SILT with trace •••••• gravel; moist (fill, 4-inch-thick root PP=0.75 tsf : zone). PP I We 2.5 to,,,, •I A MI *4:0 with some fine to coarse, angular gravel PP PP=0.5 tsf I ••'••• at 3.0 feet s.o ❖.•. 7.5 viii iii I 444 :44 becomes gray and brown with some clayEJ 10.0 •;•;•; and trace gravel at 9.0 feet :❖: .❖. I *414 12.5 •••••� •••••• PP=3.25 tsf - Very stiff, gray SILT with trace fine sand;/ 13.3 PP ® • No groundwater seepage observed moist. 13.s to the depth explored. Test pit completed at 13.5 feet. No caving observed to the depth 15.0— explored. TP-4 0 50 100 100 0.0 • 0 so . s,4 Medium stiff, brown SILT with trace ••••.; gravel; moist (fill, 4-inch-thick root • I tzone). 2.5 •� •❖• ♦♦ a0 ii•• I ••• iii a0 •i 0 DEPTH v > Z a •MOISTURE COMMENTS I FEET d MATERIAL DESCRIPTION WIo i- g CONTENT w V L. ' TP-5 0 50 100 o.o :�.�.� Soft, brown SILT with trace gravel and -Minor caving observed trom 0.0 to .:•:•: organics; moist (fill, 4-inch-thick root 4.0 feet. '- :40 zone). .•••O 2.5 •... .• ® • ••• Slow Slow groundwater seepage .; I u 9 DEPTH = MATERIAL DESCRIPTION w a~ z a •MOISTURE COMMENTS I FEET a w,,� N CONTENT% o u a 0 TP-7 0.0 •� 0 50 100 •• Soft, brown SILT with trace gravel and Moderate caving observed trom • • •••• orgnics, and occasional cobbles; moist 0.0 to 4.0 feet. ••• (fill, 4-inch-thick root zone). I • .1111• 2.5 41�4.4 41 4.4 ••••. 1111• •'•'4 ® Slow groundwater seepage I �;•••• s.o • becomes medium stiff with no organics observed at 4.0 feet. •�; at 4.0 feet � • ••... 11.•1; u DEPTH o >H Z a •MOISTURE I FEET a MATERIAL DESCRIPTION wlW 1- 2 CONTENT% COMMENTS o H V' u TP-9 ' 0 50 ,00 0 0 �;A Soft, brown SILT with some gravel and ;.;.' trace organics (fine roots); moist(fill,4- ••r •••• inch-thick root zone). .•••,•: grades to very stiff with no organics and .•;•;. occasional gravel to cobble-size asphalt I •••••••••••••:..•t PP PP=4.0 tsf pieces at 3.0 feet s.o grades to medium stiff and gray with •••• some fine sand at 5.0 feet I •.. El .❖. ANole 7.5 ;•;•; Medium dense, gray GRAVEL; moist, 7.0 •:: .11 L., O DEPTH u >= Z •MOISTURE FEET a MATERIAL DESCRIPTION wl� N CONTENT% COMMENTS p w ", 1.) ~ TP-1 1 o so 100 0.0 , - -- ❖•• Medium stiff, brown SILT; moist (fill, 3- ••••• inch-thick root zone). 2.5 •.•,. •❖ .❖ .❖ .❖ 5.0 •:•: •❖. 7.5 •ii •;;;•;• Moderate groundwater seepage •••• observed at 9.0 feet. Stiff, brown SILT with trace fine sand; 9_0 ® Moderate caving observed at 9.0 10.0— moist. feet. I - Test pit completed at 11.5 feet. 11.5 12.5— i 15.0— I TP-12 ° 50 100 0 50 100 0.0 �•�•� Soft, brown SILT with trace gravel and -Minor caving observed trom U.0 to •:•:.: organics; moist (fill, 3-inch-thick root 4.0 feet. • *•**4 zone). 44 2.5 .•;•;• becomes very stiff with occasional A: cobble-size asphalt 0 -••• p pieces and no •;•;•; organics at 2.0 feet I ••••-•• •O❖ w• 5.0 •i i i ....�, grades to stiff, gray and brown at 5.0 I 0 ;.;0 feet z •••4,41 a• • •••••� 7.5— Medium stiff, brown SILT with gray 7.0 t.9 - mottles; moist. a o -- grades to stiff at 9.0 feet o 10.o— w O - a. CD Test pit completed at 1 1.0 feet. 11.0 No groundwater seepage observedto the depth explored. ii i-7 12.5— I y - x 0 15.0— I a. 0 50 100 w aEXCAVATED BY:Western States Soil Conservation,Inc. LOGGED BY:SMD COMPLETED:05/27/05 C w a. EXCAVATION METHOD:trackhoe(see report text) G EODESIGNu ? PACTRUST-1 1 1-0 1 TEST PIT W 15575 SW Sequoia Parkway-Suite WO PortiandFx97224 Off 507.96e.8787 Pax 503.968.3068 JUNE 2005 TRI-COUNTY RETAIL CENTER TIGARD,OR FIGURE A-6 u 0 DEPTH u >H Z aJ. •MOISTURE I FEET a MATERIAL DESCRIPTION wlW N g CONTENT% COMMENTS 0 w tQ u ~ _ TP-13 I 0"0 ••••• Medium stiff, brown SILT with trace ° 50 l—Severe caving observed trom 0.0 •:•:. gravel; moist (fill, 4-inch-thick root to 5.0 feet. Z?it zone). 2.5 •••• 5.0 •• ••�• • t •••• 7.5 :i:i •••�• •• ' Very stiff, brown SILT with gray mottles 8.5 and trace clay; moist. ® • 10.0— PP PP= 1.5 tsf I J No groundwater seepage observed Test pit completed at 11.0 feet. 11.0 to the depth explored. 12.5- 1 _ 15.0— 0 50 100 I I 0 a I o cg m tii F a 0 I a a a 1- 0 O Iz 0 iii0 0 La O ' a 0 E r- 1- N 0 tY H I a a to CD EXCAVATED BY:western States Soil Conservation,Inc. LOGGED BY:SMD COMPLETED:05/27/05 ce w Ia-ev EXCAVATION METHOD:trackhoe(see report text) O a G EO DES I G N? PACTRUST-1 11-01 TEST PIT I In 503.968.3068 15575 5W Sequoia Parkway•Suite 100 w I-- Port7117 F 97224 Off 503.968.8787 Fax JUNE 2005 TRI-COUNTY RETAIL CENTER TIGARD,OR FIGURE A-7 • O = V w I DEPTH = MATERIAL DESCRIPTION wIa H a •MOISTURE COMMENTS FEET a w CD Lu Q CONTENT /o —0.0 0 50 100 ii ' Medium stiff, brown SILT with trace '- gravel; moist (fill,4-inch-thick root zone). . ! 4.1 u DEPTH o >1_,X Z a •MOISTURE I FEET a MATERIAL DESCRIPTION wIW N g CONTENT% COMMENTS p ISI IQ u i- TP-15 0 so 100 I. •• Medium stiff, brown SILT with trace •:•: ! gravel and organics; moist(fill, 4-inch- - \thick root zone, till zone to 1.25 feet). f 1.3 IStiff, brown SILT with trace clay; moist. 2.5- ® PP=2.0 tsf PP ' 5.0- I _ 7.5- becomes brown with gray mottles at 6.0 feet PP ® • PP= 1.25 tsf 10.0- with some clay at 10.0 feet I _ No groundwater seepage observed 12.5 ® to the depth explored. Test pit completed at 12.5 feet. 12.5 No caving observed to the depth ... explored. 15.0- TP-16 0 50 100 0.0 jj! 0 50 100 • Stiff, brown SILT; moist (fill, 4-inch-thick• root zone). .z.s • PP ® a • I <o ••••f o 444 12.5 •• a 5.0 with trace gravel and occasional cobbles I to 5.0 feet it7.50 . 00 ;:; grades to trace clay at 8.0 feet I 0 •♦•• a 40:4 w ♦• 0 ••••� W 10.0 •.•.. 0 •0 I 0. •••• :�;:� grades with some cobbles at 11.0 feet Moderate groundwater seepage •�❖; observed at 1 1.5 feet. E.4 12'5I Stiff, brown SILT with gray mottles, and 12-5trace clay and fine sand; moist. ® No caving observed to the depth N Test pit completed at 13.5 feet. 13.5 explored. cc 1 5.0- ' o. 0 50 100 IL aEXCAVATED BY:Western States Soil Conservation,Inc. LOGGED BY:SMD COMPLETED:05/27/05 cc w 0. EXCAVATION METHOD:trackhce(see report text) OI_ GEODESIGN= PACTRUST-111-01 TEST PIT I- Icn155759W SequoiaPortland Parkway7224 to 100 FIGURE A-9 IL Portland OR 97221 JUNE 2005 TRI COUNTY RETAIL CENTER ~ Off 503.%8.8797 Fax 903.%8.3096 TIGARD,OR • 0 9 LI w DEPTH u >H Z a •MOISTURE I FEET o MATERIAL DESCRIPTION wlW N 2 CONTENT%1-4 COMMENTS 0 I- u TP-17 o so 100 o.o ;;O Stiff, brown SILT with trace gravel; moist •:•:• (fill• , 4-inch-thick root zone). • 2.5— • Stiff, brown SILT; moist. 2.0 ® • I _ Slow groundwater seepage observed at 4.0 feet. 5.0— 7.5— I 10.0— ' No caving observed to the depth 12.5— Test pit completed at 12.0 feet. 12.0 explored. 1 - 15.0— 0 50 100 1 I 0 Ia 0 S Li; F ❑ IZ 0 o 0 I z CD to cii0 UJ 0 I ri E. F7 IS7' CO C I- 0 I 0 w < EXCAVATED BY:Western States Soil Conservation,Inc. LOGGED BY:SMD COMPLETED:05/27/05 o.w w D_cv EXCAVATION METHOD:trackhoe(see report text) 0 GEO DES I G NZ PACTRUST-1 11-01 TEST PIT I w tss7s5wSequoia A72Nsurce ioo 0TRI COUNTY RETAIL CENTER — Off 503.968.8787 Fax 503.966.3068 JUNE 2005 TIGARD,OR FIGURE A-10 . ACRONYMS AND ABBREVIATIONS • ACRONYMS AND ABBREVIATIONS AC asphalt concrete ACP asphalt concrete pavement ASTM American Society for Testing and Materials BGS below ground surface g gravitational acceleration (32.2 feet/second') H:V horizontal to vertical IBC International Building Code MCE maximum considered earthquake MSL mean sea level OSHA Occupational Safety and Health Administration OSSC Oregon Standard Specifications for Construction (2015) pcf pounds per cubic foot pci pounds per cubic inch PG performance grade psf pounds per square foot psi pounds per square inch SOSSC State of Oregon Structural Specialty Code G EO DESIG NU Basecamp-1-02:030216 www.geod es i gn i n c.co m