The URL can be used to link to this page

Report f f" i trit ® Information � a ®To Build On FILE COPY ' S . ... i . ® ng Engineering • Consulting • Testing a ` October 8, 2002 8 Vizac,3 - ooje7 5 r T z o03 —caaa za ` SWO s w 98 P Ave Mr. Ed Whitehead if Tigard Church of God 15670 Southwest 98 Avenue Tigard, Oregon - 97224 4 t` ; Subject: Geotechnical Engineering Services Report i New Administration Building . • - Tigard Church of God II 15670 Southwest 98 Avenue Tigard, Oregon 97224 PSI Report No. 704 - 25160 -1 • Dear Mr. Whitehead: Professional Service Industries, Inc. (PSI) is pleased to submit our Geotechnical Engineering Services Report for the above - referenced project. The purpose of these services was to assist you, the architect, and the engineer in designing foundations, and preparing plans and specifications for construction of the proposed new administration building. Our evaluation was completed in general accordance with PSI Proposal No. 704- 02 -P121, dated September 20, 2002. Written authorization for our services was provided by Mr. Bruce Plunkett, Building Committee Chair, on September 24, 2002. We are enclosing this summary letter along with our detailed Geotechnical Engineering Services Report for your review. gl _ Project and Site Description The new administration building will be one -story wood frame construction with a crawl space and a brick veneer constructed in the existing lawn area at the southwest corner of the existing , structure. U .L__ a _=..✓) Summary of Results (( C ; YO TIIG e7 / ) � ( ` L�J Y�L.� i�G 4s, NJi4/� k ON Two soil borings (B -1 and B -2) were completed in the project area. The general soil profile within the footprint of the proposed building was about 3 inches of topsoil with grass roots, underlain by brown, stiff, sandy silt to a depth of 7.5 to 10 feet. Below this was a stratum of brown, very loose to medium dense, silty sand that extended to the final depth of the borings, Professional Service Industries, Inc. • 6032 N. Cutter Circle, Suite 480, P.O. Box 17126 • Portland, OR 97217 • Phone 503/289 -1778 • Fax 503/289 -1918 I I J ® Information Itif.To Build On Engineering • Consulting • Testing GEOTECHNICAL ENGINEERING SERVICES REPORT NEW ADMINISTRATION BUILDING TIGARD CHURCH OF GOD 15670 SOUTHWEST 98 AVENUE TIGARD, OREGON Prepared for Tigard Church of God 15670 Southwest 98 Avenue Tigard, Oregon 97224 Prepared by PROFESSIONAL SERVICE INDUSTRIES, INC. 6032 North Cutter Circle, Suite 480 Portland, Oregon 97217 Telephone (503) 289 -1778 PSI REPORT NO. 704 - 25160 -1 October 8, 2002 I I .Y4, Professional Service Industries, Inc. Information To Build On Tigard Church of God PSI Project No. 704 - 25160 -1 October 3, 2002 _ Page 2 - 8 21.5 feet below existing grade. Groundwater was observed in the explorations performed on September 27, 2002 at approximately 17.5 to 18 feet below existing grade while drilling, and at approximately 14.5 feet below existing grade immediately after the auger was extracted from the hole. Groundwater levels should be anticipated to be higher during the wet winter months or periods of extended rainfall. Summary of Recommendations The primary geotechnical factor influencing the design and construction of the proposed project F1 will be the site preparation consisting of the removal of the upper grass top soil and softer - surface soils along with the concrete sidewalks in the area. ' Based on the results of our soil borings, it is our opinion that the proposed building may be ? `"s ' 9 p P p 9 Y supported on conventional shallow spread footings designed for a net maximum allowable soil bearing pressure of 2500 pounds per square foot (psf) when founded on the firm, undisturbed native sandy silt stratum, or on an engineered structural fill placed on this stratum. The allowable soil bearing pressure of 2500 psf is intended for dead loads and sustained live loads 1 : [ . and can be increased by one -third for the total of all loads, including short-term wind or seismic l ' loads. After the site has been stripped of topsoil and any existing soft soils, any future concrete slabs may be placed over the native, firm, sandy silt stratum, or a compacted structural fill placed on this stratum, after the subgrade has been proofrolled to confirm its firmness. t . dr .1 .... Ssr I I • . Professional Service Industries, Inc. Information To Build On gi Tigard Church of God PSI Project No. 704 - 25160 -1 II October 3, 2002 Page 2 , la General Please refer to the attached report for a more detailed summary of our analyses and III recommendations. The reader should not rely solely on this summary letter and should read the entire contents of the - attached report. If we can provide additional assistance, or observation II and testing services during construction, please do not hesitate to contact Charles Lane at (503) 978 -4703. et Respectfully Submitted, Professional Service Industries, Inc. g � . + GI N e4 :V 3944 . i OREGON 0 dS. <, Y 14 . 44, / / q 'PZES R Charles R. Lane, P.E. _ e Ken Andrieu Senior Geotechnical Engineer ' �� Staff Geologist 0 , Attachment: Geotechnical Engineering Services Report 1 NI It it C: Jackie Root- Zaik/Miller Associates I F:\ Users\ Shared \GROUPS \704 \PROJECTS\2002 projects\25160 (Tigard Church of God)\25160 -1.doc I - - Table of Contents 1.0 INTRODUCTION 1 2.0 PROPOSED CONSTRUCTION 1 3.0 PURPOSE AND SCOPE OF SERVICES 1 3.1 SUBSURFACE EXPLORATION 1 3.2 FIELD & LABORATORY TESTING 2 3.3 ENGINEERING ANALYSES 2 4.0 SITE AND SUBSURFACE FEATURES 3 4.1 SITE DESCRIPTION 3 - f 4.2 REGIONAL GEOLOGY 3 4.3 SUBSURFACE CONDITIONS 3 4.4 SEISMIC CONSIDERATIONS 4 5.0 CONCLUSIONS AND RECOMMENDATIONS 5 5.1 GEOTECHNICAL DISCUSSION 5 5.2 SITE PREPARATION 5 5.2.1 Site Preparation During Dry Weather Construction 6 5.2.2 Site Preparation During Wet Weather 6 5.3 EXCAVATIONS 7 5.3.1 Construction Dewatering 7 • 5.3.2 Excavations/Slopes 7 5.4 FOUNDATION SUPPORT 7 5.5 DRAINAGE CONSIDERATIONS 8 5.6 CONCRETE SLAB SUPPORT 9 5.7 CONSTRUCTION MONITORING 9 ,.i 6.0 GENERAL 10 6.1 USE OF REPORT 10 6.2 LEVEL OF CARE 10 Appendix: Site Location Map I Boring Location Map Boring Logs Laboratory Test Results General Notes Soil Classification Chart m U< t't' _ . . .. -, _ . 0 i __ or w i _ Geotechnical Engineering Services Report New Administration Building Tigard Church of God Ill October 8, 2002 PSI Report No. 704 - 25160 -1 f1f 1.0 Introduction Professional Service Industries, Inc. (PSI) has conducted a geotechnical evaluation for the above - referenced project site in general accordance with the scope of work as outlined in our proposal no. 704- 02 -P121, dated September 20, 2002. Written authorization for our services was provided by Mr. Bruce Plunkett for Tigard Church of God, by signing our proposal on September 24, 2002. I . 2 .0 Proposed Construction Project information was provided by Jackie Root of Zaik/Miller Associates. We have also been if furnished with drawings showing the proposed location of the new administration building and the existing facilities. We understand construction at this site is anticipated to consist of a one- ,; • story wood frame building with a brick veneer siding. The structure will utilize a crawlspace with �i', perimeter footings and interior footing pads, and a structural floor system. The wall and column loads are not currently known and have been assumed to be on the order of 2 kips per lineal foot and 30 kips, respectively with floor loads on the order of 200 psf. Maximum cuts on the order of 1 to 2 feet are anticipated with fill of 1 to 2 feet. The location of the site is shown on the attached Site Location Plan, Figure 1. It 3.0 Purpose and Scope of Services The purpose of our evaluation was to assess the subsurface soil conditions at the site in order to provide appropriate recommendations for site preparation and foundation design. In general, our evaluation included the following authorized scope of services: II 3.1 Subsurface Exploration la The purpose of this preliminary subsurface exploration and analysis was to determine the various soil profile components, determine the engineering characteristics of the materials encountered, provide information to the design engineers and architects which could be used to M .: formulate design criteria. Professional Service Industries, Inc. • Information To Build On Tigard Church of God PSI Project No. 704 - 25160 -1 October 8, 2002 Page 2 In order to ascertain soil conditions at the site, two Standard Penetration Test (SPT) soil borings ._ (B -1 through B -2) were made using our CME75 truck - mounted, hollow -stem, power auger with an automatic hammer. Soil boring locations are shown on the attached Boring Location Plan, PI Figure 2 in the Appendix. Logs of the borings are also attached in the Appendix. The Standard Penetration Test is performed by driving a 2 -inch, O.D., split -spoon sampler into the undisturbed formation located at the bottom of the advanced auger with repeated blows of a 140- pound, pin - guided, automatic safety hammer falling a vertical distance of 30 inches. The number of blows required to drive the sampler one -foot is a measure of the soil consistency — (cohesive soils) and density (non- cohesive soils). It should be noted that automatic hammers generally produce lower standard penetration test values than those obtained using a traditional safety hammer. Studies have generally indicated that penetration resistances may vary by a factor of 1.5 to 2 between the two methods. We have considered this drilling and testing methodology in our description of soil consistency for cohesive soils and density for non - cohesive soils in our evaluation of soil strength and compressibility. Soil samples were taken at 2.5 -foot intervals for the first 15 feet, and then at 5 -foot intervals to the termination depths of the borings. Select soil samples were obtained in the test borings as determined by the Project Engineer. Samples were identified in the field, placed in sealed containers, and 'transported to the laboratory for further classification and testing. 3.2 Field & Laboratory Testing • Selected samples of the subsurface soils encountered were returned to our laboratory for further evaluation to aid in classification of the materials, and to help assess their strength and compressibility characteristics. The laboratory evaluation consisted of visual and textural examinations, moisture content tests, and sieve analyses. Results of the tests are shown on the' attached boring logs and the Laboratory Test Result Summary in the Appendix. Laboratory testing was accomplished in general accordance with ASTM procedures. 3.3 Engineering Analyses Engineering analyses and recommendations regarding general foundation design including I i allowable soil bearing pressures, minimum footing depth requirements, and estimates of foundation settlement are included in this report. In addition, recommendations were developed addressing site preparation, placement and compaction of fill materials, and site preparation of concrete slab areas. Professional Service Industries, Inc. Information To Build On Tigard Church of God PSI Project No. 704- 25160 -1 October 8, 2002 Page 3 The geotechnical recommendations presented in this report are based solely on the available project information, building location, and the subsurface materials described in this report. If any of the noted information is incorrect, please inform us in writing so that we may amend the recommendations presented in this report, if appropriate and if desired by the client. PSI will not be responsible for the implementation of its recommendations when it is not notified of changes in the project. The scope of services did not include a Seismic Site Hazard Study in accordance with Section 1804.2.1 of the 1998 State of Oregon Structural Specialty Code, or an environmental evaluation for determining the presence or absence of wetlands, or hazardous or toxic materials in the soil, bedrock, surface water, groundwater, or air, on or below, or around this site. Any statements in this report or on the boring logs regarding odors, colors, and unusual or suspicious items or conditions are strictly for information purposes and do not constitute an environmental evaluation of the soils encountered. 4.0 Site and Subsurface Features 4.1 Site Description i{3 The site for the proposed administration building is located in the lawn area at the southwest corner of the existing building. It is bordered by the existing building to the north, an asphalt k' paved parking lot to the south, a lawn area with trees to the east, and a lawn area to the west. An existing concrete sidewalk runs north -south through the proposed area. The general area of the existing building and the proposed administration building is relatively level. 4.2 Regional Geology Available eolo is mapping of the area indicates that the soils within and surrounding the 9 9 project site consists of Pleistocene -Age, alluvial deposits of clay, silt, and fine sand derived from the catastrophic, periglacial flooding of the Columbia, Willamette, and Tualatin basins. These fine- grained deposits may be over 100 feet in thickness, and are underlain by volcanic bedrock units of the Miocene -Age Columbia River Basalt Group (I.P. Madin, 1990, DOGAMI Open File Report 0- 90 -2). 4.3 Subsurface Conditions Two soil borings (B -1 and B -2) were completed in the project area. The general soil profile within the footprint of the proposed building was about 3 inches of topsoil with grass roots, Professional Service Industries, Inc. Information To Build On 1 Tigard Church of God ipt • PSI Project No. 704 - 25160 -1 October 8, 2002 i Page 4 01 . underlain by a brown, stiff, sandy silt to a depth of 7.5 to 10 feet. Below this was a stratum of "I brown, very loose to medium dense,•silty sand that extended to the final depth of the borings, 21.5 feet below existing grade. The silty sand stratum is known to extend to depths of several tens of feet. Groundwater was observed in the explorations performed on September 27, 2002 pi at approximately 17.5 to 18 feet below existing grade while drilling, and at approximately 14.5 I feet below existing grade immediately after the auger was extracted from the hole. Groundwater li N levels should be anticipated to be higher during the wet winter months or periods of extended rainfall. The soil profile described above is generalized to highlight the major subsurface stratification features and material characteristics. The boring logs included in the Appendix should be IP reviewedfor specific information at individual test locations. These records include soil _ descriptions, stratifications, locations of the samples, and laboratory test data. The stratifications shown on the exploration, logs represent the conditions only at the actual boring locations. !I Variations may occur and should be expected between test locations. The stratifications represent the approximate boundary between subsurface materials and the actual transition - may be gradual. Water level information obtained during field operations is also shown on these 0 exploration logs. The samples that were not altered by laboratory testing will be retained for 60 days from the date of this report and then they will be discarded. 1 .. 4.4 Seismic Considerations IC The site falls within Seismic Zone 3 with a seismic zone factors of 0.30 as classified by Figure 16 -2 and table 16 -I of the 1998 State of Oregon Structural Specialty Code (SOSSC), effective I October 1, 2001 —an amendment to the 1997 Uniform Building Code. Based on the local � � geology and the soil conditions encountered, we recommend a soil profile type of SE with site coefficients of Ca =0.36 and Cv =0.84 in accordance with Section 1636 and Tables 16 -J, 16 -Q E and 16 -R of the SOSSC. The soil profile type recommendation reflects the estimated average soil properties for the top 100 feet of subsurface profile. la Our evaluation of the subsurface conditions at the site did not indicate a significant potential for soil liquefaction, associated with a seismic event at the site. However, it should. be noted that a ink Siesmic Site Hazard Study was beyond the present scope of services for this project. Such an NU evaluation could be performed at an additional fee with your written authorization. i . lu $i j 41 Professional Service Industries, Inc. • Information To Build On Tigard Church of God PSI Project No. 704 - 25160 -1 October 8, 2002 r, Page 5 6.0 Conclusions and Recommendations 5 ./ Geotechnical Discussion n Based on the results of our fieldwork, laboratory evaluation, and engineering analyses, it is our • i opinion that the site is suitable for the proposed structure and associated improvements ` provided the following recommendations are incorporated into the design and construction of tr . the project. il 5.2 Site Preparation In general, we recommend that all structural improvement areas be drained of surface water, 10 and stripped of surface vegetation, topsoil, highly saturated or disturbed soil, and any other deleterious materials encountered at the time of construction. Ori The depths of topsoil in our borings was about 3- inches. It is not unusual for topsoil thickness to vary from this value. The depth of removal should be determined by a representative of the Geotechnical Engineer at the time of construction. Additional site preparation will depend upon the proposed site grades and building features. t i Prior to backfilling of any excavations with structural fill, the exposed subgrade should be observed by a representative of the Geotechnical Engineer to ensure that it is ready for fill Y p 9 Y Placement. t 11, After subgrade preparation and observation have been completed, fill placement may begin. It. The first layer of fill material should be placed in a relatively uniform horizontal lift. Fill materials 'should be free of organic or otherwise deleterious materials, have a maximum particle less than ;3 inches, and have a liquid limit less than 45 percent and plasticity index less than 25. Most of iii Id the on -site soils are suitable for use as a structural fill although they will likely require significant drying. If a fine- grained silty or clayey soil is used for fill, close moisture content control will be ill required to achieve the recommended degree of compaction. All rquired structural fill materials placed should be moisture conditioned to within 2 percent of ki optimum moisture content and compacted by mechanical means to a minimum of 95 percent of t he material's maximum dry density as determined in accordance with ASTM D 1557 (Modified P roctclr). If water must be added, it should be- uniformly applied and thoroughly mixed into the Ill soil by disking or scarifying. Fill materials should be placed in accordance with the r000 nzmendations below, and placed in layers that, when compacted, do not exceed about 8 Ij !�-` Professional Service Industries, Inc. • Information To Build On II Tigard Church of God PSI Project No. 704 - 25160 -1 . October 8, 2002 Page 6 inches. Each lift of compacted engineered fill should be tested by a representative of the Ili geotechnical engineer prior to placement of subsequent lifts. 5.2.1 Site Preparation During Dry Weather Construction During the dry season, prior to the placement of any fills, all exposed subgrade surfaces should be proofrolled with a fully loaded tandem axle dump truck or similar rubber tired vehicle (i.e. water truck). Areas found to be soft or otherwise unsuitable for support of structural loads • should be overexcavated and replaced with compacted fill as described above. a The on -site, native silt soil could be considered for re -use as structural fill provided it is free from ', < organic materials and debris. Moisture conditioning, in accordance with Section 5.2, and some re- working of the on -site soils in order to facilitate compaction should be anticipated. Should wet weather grading be anticipated, use of the on -site soils as structural fill is not recommended. Selected samples of the materials to be used for structural fill should be submitted to our laboratory in order to evaluate the maximum density, optimum moisture content, and suitability of the soil for use as fill. - 5.2.2 Site Preparation During Wet Weather , l . • Additional fill material, if needed, during wet weather construction should consist of an all - weather, clean, granular fill containing less than 5 percent material passing the No. 200 sieve, 1; such as course sand, crushed rock, or course sand and gravel. During wet weather grading operations, all excavations should be performed using a smooth - bladed, tracked backhoe It working from areas where material has yet to be removed or from the already placed structural fill. Subgrade areas should be cleanly cut to firm undisturbed soil. Placement of crushed rock should follow immediately after site grading in order to provide protection of the sensitive subgrade soil during construction activities. In traffic areas, the placement of a one -foot thick granular working base is generally recommended with thicker EU sections (i.e. 18 to 24 inches) and /or geotextile fabrics recommended in heavily traveled construction traffic areas. Generally, three to six inches of crushed rock is sufficient in foot traffic t areas. The upper fine- grained soils encountered at this site are expected to be sensitive to IL disturbances caused by construction traffic and to changes in moisture content. During wet weather periods, increases in the moisture content of the soils can cause significant reduction in the soil strength and support capabilities. In addition, soils that become wet may be slow to dry and thus significantly retard the progress of grading and compaction activities. It will, therefore 9 9 9 P therefore, F __ Professional Service Industries, Inc. Information To Build On Tigard Church of God PSI Project No. 704- 25160 -1 October 8, 2002 Page 7 be advantageous to perform earthwork and foundation construction activities during dry weather. Proofrolling of excavation bottoms is likely not appropriate during wet weather grading in order to avoid disturbance of moisture - sensitive soils. Should construction take place during wet a weather, we recommend that a representative of the geotechnical engineer be present to observe the subgrade in order to evaluate whether additional preparation is indicated. • 5.3 Excavations Excavation and construction operations may expose the on -site soils to inclement weather conditions. The stability of exposed soils may rapidly deteriorate due to a change in moisture g;4 content (i.e. wetting or drying) or the action of heavy or repeated construction traffic. Accordingly, foundation and pavement area excavations should be adequately protected from the elements, and from the action of repetitive or heavy construction loadings. 5.3.1 Construction Dewatering Water seepage in excavations should be anticipated during the wet season of the year. For 11h most of the excavations for this project, pumping from sumps outside the limits of the excavation should control water seepage and surface water ponding. 5.3.2 Excavations/Slopes Temporary earth slopes may be cut near - vertical to heights of 4 feet. Excavations deeper than 4 feet should be performed in accordance with Department of Labor Occupational Safety and Health Administration (OSHA). Job site safety is the responsibility of the project contractor. 5.4 Foundation Support Based on the results of our geotechnical investigation, it is our opinion that the proposed building can be supported on conventional shallow spread footings designed for a maximum allowable soil bearing pressure of up to 2500 psf, when founded on the firm native, sandy silt stratum, or on an engineered structural fill placed on this stratum. The allowable bearing pressure is intended for dead loads and sustained live loads and can be increased by one -third It for the total of all loads, including short-term wind or seismic loads. Continuous wall and isolated column footings should be at least 18 and 24 inches in width, respectively. Wall footings exposed to weather should extend to a minimum depth of 12 inches 1 T , Professional Service Industries, Inc. . Information To Build On ill Tigard Church of God PSI Project No. 704 - 25160 -1 October 8, 2002 Page 8 t' J} beneath the lowest adjacent exterior grade to provide frost protection. Interior footings and exterior footings not exposed to weather can be located at nominal depths compatible with 7 • architectural and structural considerations. Allowable lateral frictional resistance between the base of shallow foundations and the subgrade can be expressed as the applied vertical load multiplied by a coefficient of friction of 0.30. In addition, lateral loads may be resisted by a passive earth pressure based on equivalent fluid density of 250 pounds per cubic foot (pcf) on footings poured "neat" against in -situ soils or properly backfilled with structural fill, respectively. The passive earth pressure recommendation includes a factor of safety of approximately 1.5, which is appropriate due to the amount of movement required to develop full passive resistance. We estimate that foundations designed, and constructed in accordance with the above 1 recommendations will experience total settlements generally less than 1 -inch with differential ; settlement between adjacent columns generally less than Y2-inch. I If footings are constructed during wet weather, it may be necessary to protect the foundation excavation bottoms from disturbance during construction activities.. In this regard, we il} recommend that a 3 to 4 -inch thickness of crushed rock be placed at the bottom of the footing excavations immediately after the excavation is completed. If footings are constructed during I the drier summer months, this crushed rock layer should not be required. k • The foundation excavations should be observed by a representative of PSI prior to steel or concrete placement to assess that the foundation materials are capable of supporting the design loads and are consistent with the material discussed in this report. 5.5 Drainage Considerations • i Water should not be allowed to collect in the foundation excavation, behind retaining walls, or in prepared subgrade on the construction area, either during or after construction. The subgrade beneath structures should be sloped to a low point to facilitate removal of any collected rainwater, groundwater, or surface runoff. Positive site drainage (i.e. sloping grade) should be provided to reduce infiltration of surface water around the perimeter of the building and beneath the floor area of the building. Any areas of the building which are to be developed below the exterior site grade should be provided with a well- designed, permanent drainage system in order to control hydrostatic pressures against walls, seepage of groundwater through basement walls, etc. Under no i F, Professional Service Industries, Inc. Information To Build On W - Tigard Church of God PSI Project No. 704- 25160 -1 ! October 8, 2002 . Page 9 x circumstances should surface runoff water be led into foundation drains. Foundation drains should be placed at the base of footings in order to prevent surface and shallow perched water from migrating beneath the footings. Surface run -off from roofs, parking areas, etc., should be tightlined to approved disposal areas. 5.6 Concrete Slab Support ill 3? tf Any proposed concrete slab -on -grade may be supported on structural fills placed over native subgrade after the removal of topsoil, and the upper soils have been proofrolled with a fully loaded tandem axle dump truck or similar rubber tired vehicle in order to confirm their firmness. Any soft or otherwise unsuitable areas observed should be over - excavated down to firm 1 subgrade and replaced with structural fill. i a k In order to provide uniform subgrade reaction beneath any proposed concrete slab -on- grade, we recommend that concrete slabs be underlain by a minimum of 4- inches of free - draining ( a maximum particle size of 3 /4 -inch with less than 5 percent material passing the no. 200 sieve), t well - graded gravel or crushed rock base course. Base course material should be moisture :.� conditioned to within +1- 2 percent of optimum moisture content and compacted by mechanical means to a minimum of 95 percent of the material's maximum dry density as determined in I] accordance with ASTM D1557 (Modified Proctor). Fill materials should be placed in layers that, when compacted, do not exceed about 8 inches. 5.7 Construction Monitoring i ., It is recommended that PSI be retained to examine and identify soil exposures created during project excavations in order to verify that soil conditions are as anticipated. We further recommend that the structural fills be continuously observed and tested by our representative in order to evaluate the thoroughness and uniformity of their compaction. Samples of fill materials ' should be submitted to our laboratory for evaluation prior to placement of fills on site. rY P P t it It is also recommended that PSI be retained to provide observation and testing of construction activities involved in the foundation, earthwork, and related activities of this project. PSI cannot 11 accept any responsibility for any conditions which deviated from those described in this report, nor for the performance of the foundation, if not engaged to also provide construction observation a t esting for this project. it Costs for the recommended observations during construction are beyond the scope of this kV current consultation. Such future services would be at an additional charge. -t.1 Professional Service Industries, Inc. ` Information To Build On Tigard Church of God PSI Project No. 704 - 25160 -1 Octdlber 8, 2002 Pays 10 6.0 General 1! Our conclusions and recommendations described in this report are subject to the following II genoral conditions: 6 Use of Report 1 This report is for the exclusive use of the addressee and their representative to use to design I the proposed structure described herein and prepare construction documents. The data, I ! " analyses, and recommendations may not be appropriate for other structures or purposes. We recotnmend that parties contemplating other structures or purposes contact us. In the absence l of our written approval, we make no representation and assume no responsibility to other partlris regarding this report. ! li 6.2 Level of Care Iti The recommendations contained in this report are based on the available subsurface information obtained by PSI, and design details furnished for the proposed project. If there are any revisions to the plans for this project, or if deviations from the subsurface conditions noted in thi3 report are encountered during construction, PSI should be notified in writing immediately to determine if changes in the foundation recommendations are required. If PSI is not retained to perform these functions, PSI will not be responsible for the impact of those conditions on the j . project. Services performed by the geotechnical engineer for this project have been conducted with that level of care and skill ordinarily exercised by members of the profession currently practicing in I this :area. No warranty, expressed or implied, is made. it Respectfully Submitted, Profossional Service Industries, Inc. E4D PROFF ill II! Charles R. Lane, P.E. Ken Andrieu Crs� •�,C Senior Geotechnical Enginee o�Go� A Staff Geologist C � 14 c, 9R4 E R . \s" i ' C Zaik/Miller Associates ,