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Specifications OFFICE COPY SELIG /LEE /RUEDA 1 O 213 S.W. Ash Street �P� A�Q Portland, Oregon 97204 G\-.N OF Q v 00 14 tel. 503.224.0173 VOLUME 1 BUII-V fax 503 . 224 . 4836 PROJECT MANUAL FOR: C.F.T. ELEMENTARY SCHOOL REPLACEMENT PACKAGE 1 - SITE WORK OWNER: OWNERS REPRESENTATIVE: TIGARD - TUALATIN SCHOOL DISTRICT 23J CORNERSTONE CONSTRUCTION MANAGEMENT 6960 SW SANDBURG STREET 5410 SW MACADAM AVENUE, SUITE 250 TIGARD, OREGON 97223 PORTLAND, OREGON 97201 (503) 295-0108 CONTACT: BRIAN RADABAUGH ARCHITECT: CONSTRUCTION MANAGER/GENERAL ARCHITECTS SLX CONTRACTOR: SELIG /LEE /RUEDA ARCHITECTS AND PLANNERS, LLC BAUGH /SKANSKA 224 S.W. FIRST AVENUE 2555 SW 153 DRIVE PORTLAND, OREGON 97204 BEAVERTON, OREGON 97006 (503) 224 -0173 PHONE: (503) 641 -2500 I CONTACT: RUDY SCHUVER, PROJECT MANAGER CONTACT: TODD PREDMORE i 1 ®f r%GARD. i : ±� 1 gee L etter to: acs ... Ol.ii.• .. a, • s dire , • v tl' PaTLAND, OREGON By - O F 0% 1 6 May 2003 A R C H I T E C T S T S + P L A N N E R S OFFICE COPY , 1 1 'i , , ' , [al - S Li Ir 1, GEOTECHNICAL INVESTIGATION SITE- SPECIFIC SEISMIC 1 HAZARD EVALUATION , I.. " CHARLES F. TIGARD ELEMENTARY ,li SCHOOL TIGARD, OREGON I. / fi illi' ( h :'- iii S ON 1 I C a '+ " u' A T E D i E. ' 11 AL ' ,1i ' 1 T5 PREPARED FOR f , 1 TIGARD- TUALATIN DISTRICT T i I TIGARD, OREGON FEBRUARY 2003 � GEOCON ' i NORTHWEST,INC. GEOTECHNICAL CONSULTANTS :(P) 1 . Project No. P1192 -05 -01 F ebruary 28, 2003 • i Tigard - Tualatin School District 23J Larry Hibbard Administration Center 6960 SW Sandburg Street i Tigard, Oregon 97223 . Attention: Mr. Stephen Poage Subject NEW CHARLES F. TIGARD ELEMENTARY SCHOOL TIGARD, OREGON GEOTECHNICAL INVESTIGATION AND 1 SITE - SPECIFIC SEISMIC HAZARD EVALUATION 1 Dear Mr. Poage; I In accordance with our proposal number PO3- 05 -09, dated January 31, 2003, and your authorization, we have performed a geotechnical investigation for the proposed New Charles F. Tigard Elementary School site in Tigard, Oregon. The accompanying report pi presents the findings of the geotechnical investigation and conclusions and recommendations regarding the geotechnical aspects of the proposed facility. Based on the results of this investigation, it is our opinion that the site can be developed as proposed, I provided the recommendations of this report are followed. The primary geotechnical concern associated with the development is the relatively high moisture content of near surface soils. I If you have questions regarding this report, or if we may be of further service, please contact the undersigned at your convenience. Sincerely, I GEOCON NORTHWEST, INCORPORATED .1 C 4 4 10C4 , 41..)— Z2e—el L—,A._¢_js 6L),24, 4, Heather Devine, P.E. Wesleyc-Spang, Ph`D., P.E. y 1 Geotechnical Engineer President E D PRO F ss ,-, �� 1 N f F. /Q2 I HLD:AWS Q 18281 9 cc: Mr. Brian Radabaugh, Cornerstone Construction Management OREGON Mr. Xavier Rueda, Selig Lee Rueda Architects Mr. Gerald Gotchall, Nishkian Dean `<41 4 1 6 , ' S9 u ' ob .eaL .= of - .i■ is • iee l S Pi• I 8380 SW Nimbus Avenue ® Beaverton, Oregon 97008 IS Telephone (503) 626 -9889 M Fax (503) 626 -8611 [EXPIRATION DATE• 6 /30 /eV j •' .. , I . 1 TABLE OF CONTENTS 1. PURPOSE AND SCOPE 1 2. SITE AND PROJECT DESCRIPTION 1 1 3. REGIONAL GEOLOGY 2 4. SUBSURFACE EXPLORATION AND CONDITIONS 3 1 4.1. SITE EXPLORATION 3 4.2. SUBSURFACE CONDITIONS 5 5. SITE - SPECIFIC SEISMIC HAZARD EVALUATION 6 I 5.1 SEISMIC SETTING 6 5.2. GROUND SHAKING CHARACTERISTICS 8 5.3. FAULT DISPLACEMENT AND SUBSIDENCE 9 I 5.4. SLOPE INSTABILITY 9 5.5. LIQUEFACTION 9 5.6. LATERAL SPREADING 10 1 5.7. SEICHE AND TSUNAMI INUNDATION 10 6 LABORATORY TESTING 10 pli 7. CONCLUSIONS AND RECOMMENDATIONS 10 7.1. GENERAL 10 7.2. SITE PREPARATION 11 I 7.3. PROOF ROLLING 13 7.4. FILLS 13 • 7.5. CUT AND FILL SLOPES 14 I 7.6. SURFACE AND SUBSURFACE DRAINAGE 14 7.7. FOUNDATIONS 15 • 7.8. CONCRETE SLAB -ON -GRADE 16 7.9. UTILITY EXCAVATIONS 17 111 7.10. PAVEMENT DESIGN 18 8. FUTURE GEOTECHNICAL SERVICES 18 1 9. LIMITATIONS 19 REFERENCES TABLES ,I Table 1;Crustal Faults Table 2, Asphalt Concrete Pavement Design . Table 3, Portland Cement Concrete Pavement Design I MAPS AND ILLUSTRATIONS Figure 1, Vicinity Map Figure 2, Site Plan . 1 APPENDIX A FIELD INVESTIGATION APPENDIX B ,ii LABORATORY TESTING 1 . I • GEOTECHNICAL INVESTIGATION I I. PURPOSE AND SCOPE This report presents the results of the geotechnical investigation and site - specific seismic hazard evaluation for the proposed New Charles F. Tigard Elementary School. The site is located northwest of the existing school building located at 12850 SW Grant Street in Tigard, Oregon, as shown in Figure 1, Site Vicinity Map. The purpose of the geotechnical investigation was to evaluate subsurface_soiLand_geologic conditions at_the_ site and, based - on the conditions encountered, provide conclusions and recommendations pertaining to the 1 geotechnical aspects of the construction of the replacement school. The site - specific seismic hazard evaluation was completed in general accordance with the 1997 Uniform Building Code and Oregon Structural Specialty Code 1804.2.1 and 1804.3. The scope of the field investigation consisted of a site reconnaissance, review of published geological literature, four exploratory borings, two dilatometer soundings and one cone - penetrometer sounding. A detailed discussion of the field investigation is presented in Section 4 of this report. Exploratory logs are presented in Appendix A. Laboratory tests were performed on selected soil samples obtained during the investigation to evaluate pertinent physical properties. Appendix B presents a summary of the laboratory test results, with the exception of in situ moisture content results. The results of laboratory moisture content tests are presented on the exploratory boring logs, located in Appendix A. The recommendations presented herein are based on an analysis of the data obtained 1 during the investigation, laboratory test results and our experience with similar soil and geologic conditions. This report has been prepared for the exclusive use of the Tigard - ' Tualatin School District and their agents, for specific application to this • project, in accordance with generally accepted geotechnical engineering practice. This report may not contain sufficient information for purposes of other parties or other uses. 2. SITE AND PROJECT DESCRIPTION The project site is located within T.2S, R.1W, Section 2, in Tigard, Oregon, at 12850 SW Grant Street. The approximate location is shown in the Site Vicinity Map, Figure 1. The ' development site is northwest of the existing school, and is currently used as a playing field. , Project No. P1192 -05 -01 • 1 February 28, 2003 • I The proposed project consists of the construction of a new replacement elementary school 1 with associated access driv parking lots and playing fields. The existing school is slated for demolition following the completion of the new building. Playing fields will be relocated • j to the area now occupied by the school. Based on discussions with Nishkian Dean, project structural engineer, preliminary estimates of maximum column and wall loads for the replacement school are 160 kips and 5 kips /foot, respectively. Based on the reconnaissance, the site is relatively flat. It is estimated that site grading will ,• consist of minor cuts and fills. 3. REGIONAL GEOLOGY Based on the State of Oregon Department of Geology and Mineral Industries' (DOGAMI) Open File Report 0 -90 -2, the site is mapped within an area of Pleistocene age fine - grained facies to a depth of approximately 60 feet bgs. These Pleistocene age deposits are characterized by brown to buff, unconsolidated beds and lenses of coarse - grained sand to - silt. The fine - grained facies are slack water fluvial and /or lacustrine deposits resulting from repeated temporary inundation of the Willamette Valley by Late - Pleistocene glacial outburst floods. These glacial floods originated in the Missoula Valley of Montana, passed through eastern Washington, and followed the Columbia River downstream. When these large floods entered the Portland Basin they flowed up the Willamette River and its tributaries, flooding most of the Willamette and Tualatin Valleys up to an approximate elevation of 350 1 feet MSL. The last of these glacial floods, also thought to be one of the largest, occurred about 12,400 years ago, establishing the minimum age of the silt deposit. Below the surface deposit is a Pliocene age sandstone and conglomerate of inundated beds and lenses of well sorted sand and gravel, typically referred to as the Troutdale Formation. The Troutdale Formation occurs primarily in the valleys of the Willamette, Clackamas and Sandy I Rivers, as well as along many of their tributaries. Older bedrock units are mapped at a depth of approximately 350 feet below the ground surface. 1 The USDA Soil Conservation Service "Soil Survey of Washington County, Oregon" (1982) maps the site as Woodburn Silt loam. The Woodburn Series is characterized as moderately well drained soils with reported permeability rates of 0.6 to 2.0 inches per hour. Frost penetration depth is less than 18 inches. I • 2 Project No. P1192 -05 -01 February 28, 2003 1 I ., . • ' 1 4. SUBSURFACE EXPLORATION AND CONDITIONS 1 4.1. Site Exploration The subsurface soil conditions at the Charles F. Tigard Elementary School site were determined based on the literature review, field exploration and laboratory testing. The field exploration was completed on February 5, 2003 and consisted of one cone penetrometer (CPT) sounding, two dilatometer (DMT) soundings, and four exploratory borings.. The 1, soundings and borings were completed in the approximate locations shown in Figure 2, Site Plan. 1 4.1.1. Cone Penetration Test 11 ' The cone penetration test is an in situ testing technique that provides an effective 1 method of delineating subsurface stratigraphy in areas of clays, silts, sands and fine gravel. The testing equipment consists of a 35.6 mm diameter cone equipped with a load cell, friction sleeve, strain gages, porous stone, and geophone. As the cone is I hydraulically pushed at a rate of 2 cm /sec, an electronic data acquisition system records the tip resistance, sleeve friction, and pore pressure at 0.1 -meter intervals. PI This technique provides a nearly continuous profile of the subsurface conditions encountered. Additionally, at selected depths, the advancement of the cone can be suspended and pore water dissipation rates can be measured. Shear waves can be I generated at the ground surface and the travel time for the wave to reach the geophone located within the cone recorded. Data from the CPT is used for both I shallow and deep foundation design, and liquefaction analyses. The ratio of the sleeve friction to the tip resistance (the friction ratio) provides soil classification information. At this the sounding was advanced to approximately A th s site th CPT g an pp y 60 feet below the I ground surface. The cone tip resistance and sleeve friction readings were recorded every four inches along the length of the sounding. A shear wave was generated at the ground surface at one -meter intervals within the upper 10 meters of the sounding I and at two -meter intervals below ten meters. The travel time for the wave to reach the cone tip was recorded. A shear wave velocity profile was developed for the site and is provided in Appendix A. Tip and sleeve friction data are also provided in Appendix A. I I 3 I Project No. P1192 -05 -01 February 28, 2003 • 4.1.2. Dilatometer Test I The dilatometer test provides a rational, cost - effective method to determine engineering parameters for the design of earthworks and structural foundations. It is particularly useful in silts and sands that can be difficult to sample or test by other methods. The DMT is performed in situ by pushing a blade- shaped instrument into the soil. The blade is equipped with an expandable membrane on one side that is pressurized until the membrane moves horizontally into the surrounding soil. Readings of the pressure required to move the membrane to a point that is flush with the blade (A — pressure) and to a point 1.1 mm into the surrounding soil (B — pressure) are recorded. The pressure is subsequently released and, in permeable soils below the groundwater table, a pressure reading is recorded as the membrane returns to the flush position (C — pressure). In addition, the thrust required to advance the blade to the desired test depth is recorded. The test sequence is performed at 0.2 -meter intervals to obtain a comprehensive soil profile. A material index (I a horizontal stress index (KD) and a dilatometer modulus (ED) are obtained directly from the dilatometer data. • Marchetti (1980) developed a soil classification system based on the material index. According to this system, soils with ID values less than 0.35 are classified as clay. Soils classified as sand have an ID value greater than 3.3. Material index values between 0.35 — 3.3 indicate silty clay to silty sand soils. Empirical relationships between the horizontal stress index and the coefficient of lateral earth pressure (K have been developed by Lunne et al. (1990) for clays and by Schmertmann (1983) for uncemented sands. While Lunne's method makes use of dilatometer data exclusively, Schmertmann utilizes both DMT and cone penetration data to estimate Ko. I Since the DMT is strain - controlled, the measured difference between the B- pressure and A- pressure readings (corrected for membrane stiffness) and cavity expansion theory, can be used to directly measure the soil stiffness. Assuming a Poisson's ratio, the dilatometer modulus is correlated to shear modulus, Young's modulus, and constrained modulus. The dilatometer soundings completed at this site were advanced to a depth of approximately 30 feet below the ground surface. A member of Geocon Northwest's 4 Project No. P1192 -05 -01 February 28, 2003 engineering staff recorded thrust and pressure readings every eight inches as the dilatometer blade was advanced. 1 4.1.3. Borings Four borings, located within the footprint of the proposed school building, were advanced to depths of approximately 26.5 feet bgs. The borings were completed with a trailer- mounted drill rig equipped With solid stem auger. A member of Geocon Northwest's geotechnical engineering staff logged the subsurface conditions encountered within the borings. Standard penetration tests (SPT) were performed in each boring by driving a 2 -inch outside diameter split spoon sampler 18 inches into the bottom of the boring, in general accordance with ASTM D 1586. The number of blows required to drive the sampler the last 12 of the 18 inches (blow count) are reported on the boring logs located in Appendix A at the end of this report. Disturbed bag samples were obtained from SPT testing. Service providers subcontracted by Geocon Northwest completed the borings. Exploration logs describing the subsurface conditions encountered are presented in Appendix A at the end of this report. 4.2. Subsurface Conditions The subsurface explorations were widely spaced across the site and it is possible that some local variations and possible unanticipated subsurface conditions exist. Based on the conditions observed during the reconnaissance and field exploration, the subsurface conditions, in general, consisted of the following: TOPSOIL — Approximately six inches of organic topsoil was encountered at the exploratory boring and sounding locations. WILLAMETTE SILT- In general, a moist to wet, brown silt with varying amounts of clay and fine- grained sand was encountered below the organic topsoil layer. In general, the silt was medium stiff to stiff, with the exception of a soft surface zone encountered in Boring B -4. 1 The Willamette Silt deposit extended to the maximum depth of exploration. Subsurface conditions encountered during the field investigation appear to be consistent with geologic conditions mapped within the region. 5 Project No. P1192 -05 -01 February 28, 2003 • 1 GROUNDWATER — Groundwater was encountered at depths ranging from 19 to 22 feet 1 below the ground surface. Perched water conditions were not encountered, but may be present in variable and unpredictable locations within the silt deposit. >� 5. SITE - SPECIFIC SEISMIC HAZARD EVALUATION 5.1 Seismic Setting 5.1.1. Earthquake Sources The seismicity of the Tualatin Valley Region, including The Charles F. Tigard Elementary School site, is controlled by three separate fault mechanisms. These include the Cascadia Subduction Zone (CSZ), the mid -depth intraplate zone, and relatively shallow crustal faults. The Cascadia Subduction Zone is located offshore and extends from Northern I California to British Columbia. Within this zone the oceanic Juan De Fuca Plate is being subducted beneath the continental North American Plate to the east. The interface between these two plates is located at a depth of approximately 15 to 20 kilometers. The seismicity of the CSZ is subject to several uncertainties, including the maximum earthquake magnitude and the recurrence intervals associated with various magnitude earthquakes. Anecdotal evidence of previous CSZ earthquakes has been observed within coastal marshes along the Oregon coast (Peterson et al. 1993). Sequences of interlayered peat and sands have been interpreted to be the result of large subduction zone earthquakes occurring at intervals on the order of 300 to 500 years, with the most recent event taking place approximately 300 years 1 ago. A recent study by Geomatrix (1995) suggests that the maximum earthquake associated with the CSZ is moment magnitude (M 8 to 9. This is based on an empirical expression relating moment magnitude to the area of fault rupture derived from earthquakes which have occurred within subduction zones in other parts of the world. 1 The intraplate or intraslab zone encompasses the portion of the subducting Juan De V Fuca Plate located at a depth of approximately 20 to 40 km below Western Oregon. Very low levels of seismicity have been observed within the intraplate zone in Oregon. However, much higher levels of seismicity within this zone have been recorded in Washington and California. Several reasons for this seismic quiescence in Oregon were suggested in the Geomatrix (1995) study and include changes in the direction of subduction between Oregon and British Columbia as well as the effects of volcanic activity along the Cascade Range. Historical activity associated with the 6 Project No, P1192 -05 -01 February 28, 2003 1 . • • i intraplate zone includes the 1949 Olympia (magnitude 7.1), the 1965 Puget Sound (magnitude 6.5), and the more recent 2001 Nisqually (magnitude 6.8) earthquakes. Both Geomatrix (1995) and Wong et al (2000) present estimates of Mw of 7.0 to 7.2 for the maximum moment magnitude of the intraslab zone The third source of seismicity that can result in ground shaking at the Charles F. I Tigard Elementary School site is near - surface crustal earthquakes occurring within the North American Plate. The historical seismicity of crustal earthquakes in western Oregon is higher than the seismicity associated with the CSZ and the intraplate I zone. The 1993 Scotts Mills (magnitude 5.6) and Klamath Falls (magnitude 6.0) were crustal earthquakes. Individual faults or fault zones, which have been mapped I by the Oregon Department of Geology and Mineral Industries (1991), Geomatrix (1995) and Wong et al (2000) within the near - vicinity of the site, are indicated on Table 1: Crustal Faults (all tables are presented at the end of the report). As I discussed within Wong et al (2000), the estimated maximum moment magnitude for each crustal fault was determined using empirical relationships developed by Wells I and Coppersmith (1994) between rupture length, rupture area, and earthquake magnitude. Seismic and geologic parameters such as slip rate, horizontal and vertical offset, rupture length, and geologic age have not been determined for the majority of the I faults in Table 1. This is primarily due to the lack of surface expressions or exposures of faulting because of urban development and the presence of late Quaternary soil deposits that overlie the faults. The low level of historical seismicity R (particularly for earthquakes greater than magnitude 5) and lack of paleo- seismic data results in large uncertainties when evaluating individual crustal fault maximum I magnitude earthquakes and recurrence intervals, and limits the available knowledge of characteristic motions of estimated maximum moment earthquakes. • i 5.1.2. Historical Seismicity I The historical seismicity of the site and the vicinity was determined based upon the review of the September 1993 and November 1995 issues of Oregon Geology and I on the analysis of the 150 year Oregon earthquake catalog, DOGAMI Open -File Report 0 -94 -4. OFR 0 -94 -4 is a database of 15,000 Oregon earthquakes that occurred between 1833 and October 25, 1993. In order to establish an estimated I Richter Magnitude for those seismic events that do not have such a recording, the Gutenberg and Richter, 1965 relationship, M = (2/3) MMI +1, was applied to those I earthquakes that only had a reported Modified Mercalli Intensity (MMI). The MMI 7 I Project No. P1192 -05 -01 February 28, 2003 I scale is a means of estimating the size of an earthquake using human observations and reactions to the earthquake. The MMI scale ranges from I to XII, with XII representing the highest intensity. A search of the database was conducted to determine the number and estimated magnitude of earthquakes that have taken place within 50 kilometers of the site. The information derived from the Oregon earthquake catalog indicates that ten magnitude M5.0 and greater earthquakes occurred within the search zone. Three of these ten were greater than M5.0. M5.7 in 1877 was the largest recorded magnitude within the 50 -km search area. 5.2. Ground Shaking Characteristics I • 5.2.1. Several studies have been published which present probability -based levels of ground motion for Western Oregon. Studies reviewed for this report include Geomatrix (1995) and United States Geological Survey (1996). These probabilistic studies incorporate the seismic characteristics of faults and seismic zones, including fault location and geometry, slip rate, and magnitude, to develop estimates of ground or bedrock shaking for different return periods (or probability of exceedance at different time periods). Within Western Oregon large uncertainties exist in probabilistic analyses due to the lack of significant historical seismicity and the uncertainty associated with seismic source characterization. The study by Geomatrix (1995) estimated peak bedrock horizontal accelerations in the site vicinity of 0.20g, 0.27g, and 0.38 for return periods of approximately 500 years, 1,000 years, and 2,500 years, respectively. I The United States Geological Survey "National Seismic Hazard Mapping Project" (1996) estimated peak bedrock horizontal accelerations of 0.19g, 0.27g, and 0.39g also for return periods of approximately 500, 1,000, and 2,500 years, respectively. 5.2.2. Design Ground Shaking Parameters For buildings designed in accordance with the current Uniform Building Code (UBC) a soil characteristic called "Soil Profile Type" is used to account for the I effect of the underlying soil conditions on bedrock motion. Based on the Seismic Rehabilitation Guidelines published by the Federal Emergency Management Agency (FEMA), where reliable shear wave velocity data 8 Project No. P1192 -05 -01 February 28, 2003 1 1 are available for a site, such data should be used to classify the site. The soil shear wave velocity determined from the seismic cone penetrometer test, along with data from DOGAMI Open -File -Report 0 -95 -7, was used to develop the average soil shear wave velocity within the upper 100 feet of the site. The shear wave velocity profile of the upper 60 feet, measured at the site, is shown in the shear wave velocity profile provided in Appendix A. The average shear wave velocity from 60 to 100 feet was extrapolated from the data acquired at the site. Based on this information, the calculated average soil shear wave velocity within the upper 100 feet, determined in accordance with the procedures outlined in UBC Section 1636 "Site Categorization Procedure ", was approximately 750 feet per second. An average shear wave velocity between 600 feet per second and 1200 I feet per second places the site within Soil Profile Type SD. It is recommended that a seismic zone factor of 0.3 for UBC Zone 3 be used for structural seismic analysis of the proposed building. Seismic design coefficients of C equal to 0.36 and C, equal to 0.54 are recommended based on Soil Profile Type SD. 5.3. Fault Displacement and Subsidence - Based on the literature review, identified faults were not mapped within the boundaries of the site or within adjacent properties. Evidence was not encountered during the field investigation to suggest the presence of faults within the property. The potential for fault displacement and associated ground subsidence at the site is considered remote. 5.4. Slope Instability Earthquake induced landslides generally occur on steep slopes composed of weak soil or bedrock. Among the factors that influence seismic induced landsliding include earthquake intensity, topographic relief, ground water, and soil or bedrock type. Earthquakes can also reactivate existing landslides. Based on the relatively flat site topography and field observations, the site is estimated to have a low earthquake induced slope instability hazard. 5.5. Liquefaction Liquefaction can cause aerial and differential settlement, lateral spreading, and sudden loss ' of soil shear strength. Soils prone to liquefaction are typically loose, saturated sands and, to a lesser degree, silt. Liquefaction analysis consists of computing the cyclic shear stresses induced in the soil by seismic shaking and calculating the cyclic shear strength (resistance) of the soil that is available to resist the seismic loading. Comparison - of the soil shear 9 1 Project No. P1192 -05 -01 February 28, 2003 I strength to the induced seismic shear stress determines the susceptibility of the underlying 1 soil to liquefaction or shear strength loss. The results of these analyses indicate that an isolated lens at approximately 40 feet below the ground surface, comprising approximately 1 0.5 feet, may be marginally susceptible to liquefaction under a design M6 earthquake. Should liquefaction of this lens occur, it is estimated that dynamically induced settlement would be less than one inch and surface expressions would be negligible. 5.6. Lateral Spreading Lateral spreading is a liquefaction related seismic hazard that may adversely impact some sites. Areas subject to lateral spreading are underlain by liquefiable sediments and are sloping sites or are flat sites adjacent to an open face. Based upon a review of the site subsurface conditions and flat topography, it is determined that the site has negligible I potential for lateral spreading. 5.7. Seiche and Tsunami Inundation ' There is not a potential for seiche- and tsunami - related damage at the site due to the distance of the site from waterways, lakes, and coastal areas. - 6. LABORATORY TESTING Laboratory testing was performed on selected soil samples to evaluate moisture content, 1 grain size distribution and plasticity. Visual soil classification was performed both in the field and laboratory, in general accordance with the Unified Soil Classified System. Moisture content determinations (ASTM D 2216) were performed on soil samples to aid in classifying the soil. Grain size analyses were performed on selected samples using procedures ASTM D 1140 and ASTM D 422. The plasticity index was determined in genera! accordance with ASTM D 4318. Moisture contents are indicated on the boring logs, which are located in Appendix A of this report. Other laboratory test results for this project are summarized in Appendix B. • 7. CONCLUSIONS AND RECOMMENDATIONS I 7.1. General 7.1.1. It is our opinion that the proposed project is geotechnically feasible, provided the recommendations of this report are followed. The primary geotechnical concern associated with the project development is the high in situ moisture content of the near - surface, moisture - sensitive soils. 10 .11 Project No. P1192 -05 -01 February 28, 2003 1 111 7.1.2. Moisture contents of near - surface soils were wet of optimum at the time of the investigation. Recommendations for both dry weather site preparation and wet weather site preparation in moisture - sensitive soils are provided, however, dry weather construction at this site is recommended. It is recommended that the project budget include costs for wet weather construction, regardless of the time of year construction is scheduled to occur. 7.2. Site Preparation 7.2.1. Prior to beginning construction, the areas of the site to receive fill, footings or pavement should be stripped of vegetation, topsoil, non - engineered fill, previous ' subsurface improvements, debris, and otherwise unsuitable material, down to firm native soil. Topsoil thickness of approximately six inches was encountered in the playing fields during the investigation. Any structures not to be incorporated into the development should be removed in their entirety. It is understood that the existing school will be demolished following the completion of the new school. Excavations made to remove previous , subsurface improvements or unsuitable soils in structural areas should be backfilled with structural fill per Section 7.4 of this report. 7.2.2. Recommendations for both dry weather and wet weather site preparation are 1 provided in the following sections. However, due to the moisture sensitive near surface soils, it is recommended that the site be prepared during dry weather. 7.2.3. Dry Weather Site Preparation • Subgrades in pavement and structural areas that have been disturbed during stripping or cutting operations should be scarified to a depth of at least eight inches. The scarified soil should be moisture conditioned as necessary to achieve the proper moisture content, then compacted to at least 92% of the maximum dry density as determined by ASTM D -1557. Minimum compaction for the eight inches immediately underlying pavement sections should be 95 %. Even during dry weather it is possible that some areas of the subgrade will become soft or may "pump," particularly in poorly drained areas or where soft clay is encountered. Soft or wet areas that cannot be effectively dried and compacted should be prepared in accordance with Section 7.2.4. 7.2.4. Wet Weather Preparation 1 11 Project No. P1192 -05 -01 February 28, 2003 During wet weather, defined as whenever adequate soil moisture control is not 1 possible, it may be necessary to install a granular working blanket to support construction equipment and provide a firm base on which to place subsequent fills and pavements. Commonly, the working blanket consists of a bank run gravel or pit run quarry rock (six to eight inch maximum size with no more than 5% by weight passing a No. 200 sieve). A member of Geocon Northwest's engineering staff should be contacted to evaluate the suitability of the material before installation. The working blanket should be installed on a stripped subgrade in a single lift with trucks end - dumping off an advancing pad of granular fill. It should be possible to strip most of the site with careful operation of track - mounted equipment. However, during prolonged wet weather, or in particularly wet locations, operation of this type of equipment may cause excessive subgrade disturbance. In some areas final stripping and /or cutting may need to be accomplished with a smooth - bucket trackhoe, or similar equipment, working from an advancing pad of granular, fill. After installation, the working blanket should be compacted by a minimum of four complete passes with a moderately heavy static steel drum or grid roller. It is recommended that Geocon Northwest be retained to observe granular working blanket installation and compaction. The working blanket must provide a firm base for subsequent fill installation and compaction. Past experience indicates that about 18 inches of working pad is normally required. This assumes that the material is placed on a relatively undisturbed subgrade prepared in accordance with the preceding recommendations. Areas used as haul routes for heavy construction equipment or construction staging areas may require a work pad thickness of two feet or more. In particularly soft areas, a heavy - grade, non - degradable geotextile fabric installed on the subgrade may reduce the thickness of working blanket required. The fabric should have a minimum puncture resistance of 80 pounds and a minimum Mullen Burst strength of 300 psi. 1 Construction practices can affect the amount of work pad necessary. By using tracked equipment and special haul roads, the work pad area can be minimized. The routing of dump trucks and rubber tired construction equipment across the site can require extensive areas and thicknesses of work pad. Normally, the design, installation and maintenance of a work pad are the responsibility of the contractor. 1 • 12 Project No. P1192 -05 -01 February 28, 2003 1 1. . Lime or cement treatment may be a suitable alternative wet - weather construction e for gu th Successful cement techniqu treatment the is sub dependent rade conditions upon enco moisture ntered content at is of site. the subgrade lime soilsor , • weather conditions at the time of treatment, and adequate mixing of the soil and lime or cement. It is recommended that cement treated soils have a three -day, unconfined compressive strength of 250 psi. Cement or lime treatment design is typically the responsibility of the contractor. 7.3. Proof Rolling 7.3.1. Regardless of which method of subgrade preparation is used (i.e. wet weather or dry weather), it is recommended that, prior to fill placement or .base course installation, the subgrade or granular working blanket be proof - rolled with a fully- loaded 10- to 12 -yard dump truck. Areas of the subgrade that pump, weave or appear soft or muddy should be scarified, dried and compacted, or .overexcavated and backfilled with structural granular fill per Section 7.4. If a significant length of time passes between fill placement and commencement of construction operations, or if significant traffic has been routed over these areas, the subgrade should be similarly proof - rolled before final placement of asphalt or concrete. It is recommended that a member of our geotechnical engineering staff observe the proof -roll operation. 1 7.4. Fills 7.4.1 Structural fills should be constructed on a subgrade that has been prepared in accordance with the recommendations in Section 7.2 of this report. Structural fills should be installed in horizontal lifts not exceeding about eight inches in thickness, and should be compacted to at least 92% of the maximum dry density for the native silt soils, and 95% for imported granular material. Compaction should be 1 referenced to ASTM D -1557 (Modified Proctor). The compaction criteria may be reduced to 85% in landscape, planter or other non - structural areas. 7.4.2. During dry weather when moisture control is possible, structural fills may consist of native material, free of topsoil, debris and organic matter, which can be compacted to the preceding specifications. However, if excess moisture causes the fill to pump or weave, those areas should be scarified and allowed to dry, and then be 1 recompacted, or removed and backfilled with compacted granular fill as discussed in Section 7.2 of this report., 1 13 Project No. P1192 -05 -01 February 28, 2003 1 7.4.3. The native, non - organic silt would generally be acceptable for structural fills if properly moisture conditioned. Near - surface moisture contents at the time of the field investigation ranged from approximately 27% to 32 %. Based on experience 1 with similar soil types the optimum moisture content for compaction is approximately 15% at a maximum dry density of approximately 115 pcf. Drying operations, including discing and aeration, should be anticipated for the native soils (even during dry months). 7.4.4 During wet - weather grading operations, Geocon Northwest recommends that fills consist of well - graded granular soils (sand or sand and gravel) that do not contain 1 more than 5% material by weight passing the No. 200 sieve. In addition, it is usually desirable to limit this material to a maximum three inches in diameter for future ease in the installation of utilities. 7.5. Cut and Fill Slopes 7.5.1. Cut slopes should be sloped no steeper than 2H:1 V. These values assume that the slopes will be protected from erosion and that significant drainage will not occur over the face of the slope. They further assume that no loads will be imposed within a horizontal distance of one -half of the slope height measured from the top of the slope face. Cut slopes should be constructed with a smooth bucket excavator to minimize subgrade disturbance. Slope drainage may be required if springs, seeps, or groundwater are encountered. 7.5.2. Fill slopes should be obtained by placing and compacting material beyond the 1 design slope and then excavated back to the desired grade or by other means that will result in a dense, compacted sloped face. Fill compaction should be as stated in Section 7.4. Filled slopes should not be graded steeper than 2H:1V and no loads should be imposed within a horizontal distance of one -half of the slope height. 7.5.3. The face of the cut or fill slope should be protected from erosion by applying 1 vegetation or other approved erosion control material as soon as practicable after construction. 7.6. Surface and Subsurface Drainage 111 7.6.1. During site contouring, positive surface drainage should be maintained away from foundation and pavement areas. Additional drainage or dewatering provisions may 14 Project No. P1192 -05 -01 February 28, 2003 1 1 be necessary if soft spots, springs, or seeps are encountered in subgrades. Where possible, surface runoff should be routed independently to a storm water collection system. 1 7.6.2. Drainage systems should be sloped to drain by gravity to a storm sewer or other positive outlet. 7.6.4. Drainage and dewatering systems are typically designed and constructed by the contractor. Failure to install necessary subsurface drainage provisions may result in premature foundation or pavement failure. 7.7. Foundations 7.7.1. The following foundation recommendations are based on estimated maximum column and wall loads of 160 kips and 5 kips /foot, respectively. 7.7.2. Spread and perimeter foundation support for proposed structures may be obtained from the near - surface, non - organic, native silt soil or from structural fill_ installed in accordance with our recommendations. 7.7.3. Spread and perimeter footings should be at least 12 inches wide and should 1 extend at least 18 inches below the lowest adjacent pad grade. Foundations having these minimum dimensions that are founded on firm native soils or engineered fill may be designed for an allowable soil bearing pressure of 3,000 1 pounds per square foot (psf). 1 7.7.4. When encountered at bottom of foundation elevation, soft and /or saturated soils may require overexcavation. 7.7.5. Gravel or lean concrete may need to be placed in the bottom of the footing excavation to reduce soil disturbance during foundation forming and construction. 7.7.6. The allowable bearing pressure given above may be increased by one -third for 1 short term transient loading, such as wind or seismic forces. 7.7.7. Lateral loads may be resisted by sliding friction and passive pressures. A base friction of 40% of the vertical load may be used against sliding. An equivalent fluid weight of 300 pcf may be used to evaluate passive resistance to lateral loads. 15 ' Project No. P1192 -05 -01 February 28, 2003 1 7.7.8. Foundation settlements for the loading expected ected for this project are p estimated to be less than one inch, with not more than one -half inch occurring as differential settlement. 1 7.7.9. Geocon Northwest recommends that foundation drains be installed at or below the 1 elevation of perimeter footings to intercept potential subsurface water. 7.8. Concrete Slab -on -Grade 7.8.1. Subgrades in floor slab areas should be prepared in accordance with Section 7.2 1 of this report. Floor slab areas should be proof- rolled with a fully loaded 10- to 12- • yard dump truck to detect areas that pump, weave, or appear soft or muddy. When detected these areas should be overexcavated and stabilized with compacted granular fill. 1 7.8.2. A minimum six -inch thick layer of compacted 3 /4-inch minus material should be installed over the prepared subgrade to provide a capillary barrier and to minimize subgrade disturbance during construction. The crushed rock or gravel material should be poorly - graded, angular and contain no more than 5% by weight passing the No. 200 Sieve. 7.8.3. A modulus of subgrade reaction of 100 pci is recommended for design. 1 7.8.3. The fine - grained near - surface soils at the site have high natural moisture contents and low permeability. These characteristics indicate that high ground moisture may develop under floor slabs during the life of the project. The difference in moisture content between the air in the subgrade soil and the air in the finished 1 building may cause water vapor to travel upward. The resulting water vapor pressure will force migration of moisture through the slab. This migration can result in the loosening of flooring materials attached with mastic, the warping of wood flooring, stain concrete, and in extreme cases, mildewing of carpets and building contents. To retard the migration of moisture through the floor slab, 1 Geocon Northwest recommends installing a 10 -mil polyethylene vapor retarding membrane below the concrete slab. Installation of the membrane should be in conformance with product manufacturer's specifications. A minimum 6 -inch under - slab section of crushed rock, as recommended in Section 7.8.2, (or underslab drainage system) should be placed as a capillary break above the subgrade and 1 below the vapor retarder. Any moisture that has accumulated on the vapor retarding membrane should be removed prior to the concrete pour. Concrete with 1 16 • Project No. P1192 -05 -01 February 28, 2003 a minimum compressive strength of 4000 psi and a water /cement ratio of less than 0.48 is recommended. In the absence of freezing temperatures, wet curing of the 1 concrete slab is recommended. • 7.9. Utility Excavations 7.9.1. Based on the subsurface explorations, difficult excavation characteristics are not anticipated. 7.9.2. Excavations deeper than four feet, or those that encounter groundwater, should be sloped or shored in conformance with OSHA regulations. Shoring systems are typically contractor designed. 7.9.3. Perched water was not encountered during the field investigation, however perched water conditions may occur in variable and unanticipated areas within the Willamette Silt deposit. Near - surface perched groundwater may be encountered during construction. Excavation dewatering may be necessary if substantial flow of groundwater is encountered. Water removed from excavations should be routed to non - structural areas of the site. Dewatering systems are typically designed and installed by the contractor. 7.9.4. Utilities should be bedded in sand within one conduit diameter in all directions, prior to the placement of coarser backfill. Trench backfill should be lightly compacted within two diameters or 18 inches, whichever is greater, above breakable conduits. The remaining backfill, to within 12 inches of finished grade, • should be compacted to 92% of the maximum dry density as determined by ASTM D1557. In structural areas, the upper foot of backfill should be compacted to 95% of the maximum dry density. 7.9.5. Backfill in utility trenches that will be spanned by building foundations should be compacted to 95% of the maximum dry density as determined by ASTM D1557 above the conduit zone. t 1 17 Project No. P1192 -05 -01 February 28, 2003 1 • 7.10. Pavement Design 1 7.10.1. Near surface soil samples were evaluated to determine pavement design parameters. A CBR of 3 at 95% compaction and a resilient modulus of 4,500 psi were used for pavement design. 7.10.2. Alternate pavement designs for both asphalt and portland cement concrete (pcc) 1 are presented in Tables 2 and 3. Pavement designs have been prepared in accordance with accepted AASHTO design methods. A range of pavement designs for various traffic conditions is provided in the tables. The designs assume that the top eight inches of pavement subgrade will be compacted to 95% ASTM D -1557. Specifications for pavement and base course should conform to current Oregon State Department of Transportation specifications. Additionally, the base rock should contain no more than 5% by weight passing a No. 200 Sieve, and the 1 asphaltic concrete should be compacted to a minimum of 91 % of ASTM D2041. 1 7.10.3. Pavement sections were designed using AASHTO design methods, with an . assumed reliability level (R) of 90 %. Terminal serviceability of 2.0 for asphaltic concrete, and 2.5 for portland cement concrete were assumed. The 18 kip design axle loads are estimated from the number of trucks per day using State of Oregon typical axle distributions for truck traffic and AASHTO load equivalency factors, and 1 assuming a 20 year design life. The concrete designs were based on a modulus of rupture equal to 550 psi, and a compressive strength of 4000 psi. The concrete sections assume plain jointed or jointed reinforced sections with no load transfer devices at the shoulder. • • 7.10.4. In areas where construction traffic and staging areas are anticipated, a minimum of 18 inches of rock underlain by a geotextile fabric is recommended, regardless of the final design section. 1 8. FUTURE GEOTECHNICAL SERVICES The analyses, conclusions and recommendations contained in this report are based on site 1 conditions as they presently exist, and on the assumption that the subsurface investigation locations are representative of the subsurface conditions throughout the site. It is the nature 1 • of geotechnical work for soil conditions to vary from the conditions encountered during a normally acceptable geotechnical investigation. While some variations may appear slight, 18 Project No. P1192 -05 -01 February 28, 2003 1 1 .� their impact on the performance of structures and other improvements can be significant. Therefore, it is recommended that Geocon Northwest be retained to observe portions of this 1 project relating to geotechnical engineering, including site preparation, grading, compaction, foundation construction and other soils related aspects of construction. This will allow 1 correlation of investigative observations and findings to actual soil conditions encountered during construction and evaluation of construction conformance to the recommendations put forth in this report. A copy of the plans and specifications should be forwarded to Geocon Northwest so that 1 they may be evaluated for specific conceptual, design, or construction details that may affect the validity of the recommendations of this report. The review of the plans and specifications will also provide the opportunity for Geocon Northwest to evaluate whether the recommendations of this report have been appropriately interpreted. 1 1 9. LIMITATIONS Unanticipated soil conditions are commonly encountered during construction and cannot always be determined by a normally acceptable subsurface exploration program. The recommendations of this report pertain only to the site investigated and are based upon the 1 assumption that the soil conditions do not deviate from those disclosed in the investigation. If variations or undesirable conditions are encountered during construction, or if the proposed construction will differ from that anticipated herein, Geocon Northwest should be notified so that supplemental recommendations can be given. 1 This report is issued with the understanding that the owner, or his agents, will ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and incorporated into the plans. The findings of this report are valid as of the present date. However, changes in the 1 conditions of a property can occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review should 1 such changes occur. 1 19 Project No. P1192 -05 -01 February 28, 2003 1 if you have any questions regarding this report, or if you desire further information, please 1 contact the undersigned at (503) 626 -9889. i GEOCON NORTHWEST, INC. • Heather Devine, P.E. Wesley Spang, Ph.D., P.E. Geotechnical Engineer President 1 1 1 1 1 1 1 1 1 1 1 20 Project No. P1192 -05 -01 February 28, 2003 1 CFT ES - SITE WATER DISTRIBUTION SECTION 02510 - WATER DISTRIBUTION PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section. B. Public Improvements shall comply with "City of Tigard Public Improvement Design Standards." 1 1.2 SUMMARY A. This Section includes water - distribution piping and specialties outside the building for the following: 1. Water services. L2. _ Fire - service mains. 3. Combined water service and fire - service mains. 4. Aboveground water piping for applications other than water - service piping. i B. Utility - furnished products include water meters that will be furnished to the site and installed by utility personnel. Contractor shall provide and install all itmes and accessories not provided and installed by the utility., ready for installation. 1.3 DEFINITIONS A. Combined Water Service and Fire - Service Main: Exterior water piping for both domestic -water and fire - suppression piping. B. iEire= ServiceMain: Exterior fire- suppression -water piping. / C. Fire- Suppression -Water Piping: Interior fire- suppression -water piping. D. Water - Distribution Piping: Interior domestic -water piping. I1 E. Water Service: Exterior domestic -water piping. F. The following are industry abbreviations for plastic materials: 1. PA: Polyamide (nylon) plastic. 2. PE: Polyethylene plastic. 3. PEX: Crosslinked polyethylene plastic. 4. PP: Polypropylene plastic. 5. PVC: Polyvinyl chloride plastic. 6. RTRF: Reinforced thermosetting resin (fiberglass) fittings. 7. RTRP: Reinforced thermosetting resin (fiberglass) pipe. 1 , WATER DISTRIBUTION 02510 - 1 li CFT ES - SITE WATER DISTRIBUTION 1.4 SUBMITTALS A. Product Data: For the following: I , 1. Piping specialties. 2. Valves and accessories. I 3. Water meters and accessories. 4. Backflow preventers and assemblies. 5. Protective enclosures. • 6. Fire hydrants. 7. Flushing hydrants. 8. Fire department connections. 9. Alarm devices. I 10. Post hydrants. 11. Drinking fountains. B. Shop Drawings: For the following: I 1. Precast concrete vaults, including frames and covers, ladders, and drains. 2. Wiring Diagrams: Power, signal, and control wiring. 4 C. Coordination Drawings: For piping and specialties including relation to other services in same area. Show piping and specialty sizes and valves, meter and specialty locations, and elevations. D. Field Quality- Control Test Reports: From Contractor. 1 E. Operation and Maintenance Data: For specialties to include in emergency, operation, and maintenance manuals. Include the following: 'i 1. Water meters. 2. Valves. I 3. Backflow preventers. 4. Protective enclosures. 5. Fire hydrants. 6. Flushing hydrants. ' 7. Post hydrants. 8. Drinking fountains. e 1.5 QUALITY ASSURANCE A. Product Options: Drawings indicate size, profiles, and dimensional requirements of piping and ' specialties and are based on the specific system indicated. Refer to Division 1 Section "Product Requirements." B. Regulatory Requirements: r 1. Comply with requirements of utility company supplying water. Include tapping of water mains and backflow prevention. 2. Comply with standards of authorities having jurisdiction for potable - water - service piping, including materials, installation, testing, and disinfection. 3. Comply with standards of authorities having jurisdiction for fire - suppression water- service piping, I including materials, hose threads, installation, and testing. C. Piping materials shall bear label, stamp, or other markings of specified testing agency. a WATER DISTRIBUTION 02510 - 2 l Project No. 9523/9524 i 3-, / 4 A) Tigard Elementary School Remodel and LUEY ARCHITECTS Tualatin Elementary School Remodel 11945 SW Pacific Hwy, Suite 301 Tigard - Tualatin School District 23 -J Tigard, OR 97223 Tigard, Oregon (503) 684 -3622 ADDENDUM NO. 1 March 29, 1996 The following additions to, deletions from and clarifications of the Contract Documents govern insofar as they apply and shall take precedence over those portions of the original Contract Documents to which they refer. Where any part of the Contract Documents is changed or voided by the following addendum items, the unaltered provisions shall remain in effect. This addendum forms a part of the Contract Documents. Acknowledge receipt of it in the space provided in the Bid Form. PROJECT MANUAL Item No. 1: Document B Instruction to Bidders A. At 1.03 A 5, change Substantial Completion date from August 23, 1996 to "August 16, 1996 ". Item No. 2: Specification Section 01400 A. At 1.03 A 1, change State of Washington to "State of Oregon ". Item No. 3: Specification Section 08305 A. At 2.01 A 2, change Milcor access door from "Style M" to "Style K" with No. 66 expansion casing bead. Item No. 4 Specification Section 15835 A. At 2.02 H, add the following: "The unit ventilator manufacturer shall provide the controls required to effect the sequence of operation defined in Section 15985, including interface to field mounted steam sensor /controller. This control must be pre- engineered, preprogrammed and pretested for each unit and shall be factory installed before shipment. The manufacturer shall provide this DDC controller in each unit ventilator. The unit ventilator manufacturer's representative shall provide start-up services to ensure the sequence of operation in Section 15985 is accomplished." Item No. 5 Specification Section 15870 A. At 2.01, delete paragraph E in its entirety. Item No. 6 Specification Section 15940 A. At 2.03, change paragraph E to read: "Mount unit on curb as indicated on the drawings." Tigard ES Remodel and Tualatin ES Remodel Addendum No. 1, Page 1 of 5 Project No. 9523/9524 Item No. 7 Specification Section 15985 A. At 1.03, add the following: B. It shall be the responsibility of the Contractor to make complete and functioning systems installed under this contract, including interfacing the equipment manufacturer's controls to field installed controls. Mechanical systems will not be accepted by-the Owner until their satisfactory operation has been demonstrated to the Owner's Representative. Satisfactory operation requires that all controls sequence of operations defined herein are accomplished. The unit ventilator manufacturer's representative shall provide start-up services to ensure manufacturer's controls as specified. Coordinate system commissioning with the manufacturer's representative." B. At 3.01, change paragraph A to read: Day / Night thermostat shall maintain 72 degree F space temperature during the day and no less than 60 degree F space temperature during the night or unoccupied period by cycling unit fan motor and modulating steam control valve, if steam is detected by steam pressure sensor controller." DRAWINGS (Tigard Elementary School) Item No. 8 Sheet No. 4 A. At Finish Schedule Notes, add "as required for mechanical and electrical work" to the end of note 1. Item No. 9 Sheet No. 8 A. At 1/8 Building "C" Reflected Ceiling Plan, shift ceiling grid at Classroom 17, 1.9, .21 and 23 to align with light fixtures similar to those shown at Classroom 18, 20, 22 and 24. Item No. 10 Sheet No. P1 A. At General Notes, add the following: "3. Temporarily disconnect existing fixtures which are to remain in rooms 2A and 4A to allow for new wainscot and floor installation. Re- connect fixtures after the aforementioned installation. Coordinate with other trades." B. At Drawing Notes change note 7 to read: "Remove (E) flush valve from urinal. Provide (N) Sloan Model 186 -1 flush valve." Item No. 11 Sheet No. P2 A. At General Notes add the following: "3. Temporarily disconnect existing fixtures which are to remain in rooms 11A and 11C to allow for new wainscot installation. Re- connect fixtures after the aforementioned installation. Coordinate with other trades." B. At Drawing Notes, change note 10 to read: "Remove (E) flush valve from urinal. Provide (N) Sloan Model 186 -1 flush valve." Item No. 12 Sheet No. P3 A. At General Notes, add the following: "3. Temporarily disconnect existing water closet in room 40 to allow for new floor installation. Re- connect fixture after the aforementioned installation. Coordinate with other trades." Tigard ES Remodel and Tualatin ES Remodel Addendum No. 1, Page 2 of 5 V -% Project No. 9523/9524 Item No. 13 Sheet No. E3 A. Building Electrical Plan 1/E3: 1. At Classroom 9, move the 3" conduit entry point from middle of East wall to South East corner of classroom. Conduit to extend up to just below ceiling to allow for routing of communication cabling exposed. 2. At Classroom 14, change Note Mark #6 pointing to light fixtures to Note Mark #5. B. At General Notes, add the following additional notes: 7. Provide one 3" C. stubbed out on either side of wall at ceiling on North side of soffit between Classrooms 9 & 10 and Classrooms 10 & 11. 8. Provide one 2" C. stubbed out on either side of wall at ceiling on North side of soffit between Rooms 11 & 11c, llc & 11a, l la & 12, 12 & 13, 13 & 14, 14 & 15. 9. Provide one 2" C. stubbed out on either side of wall at ceiling between Classrooms 15 & 16. Verify exact location prior to rough -in. C. At Drawing Notes, change notes as follows: 1. Change note #6 to read "Not Used" 2 Delete from note #8 the sentence: "Must be tie wrapped and secured to wall in location safe from damage." DRAWINGS (Tualatin Elementary School) Item No. 14 Sheet No. 4 A. At Room Finish Schedule, delete note 1 from remark column for Classroom B 1. Item No. 15 Sheet No. 5 A. At 2/5 Building "C" Floor Plan, change dimension of ceiling access door from 2' -6" x 3'- 0" to 2' -0" x 3' -0" at Boys C16. Item No. 16 Sheet No. 6 A. At 1/6 Building "A" East Elevation, delete notes reference to remove existing gutter and replace with new PPM gutter. Gutter has since been replaced by others. Item No. 17 Sheet No. 8 A. At 11/8 interior elevation C, change the reference target to read "11/9" Item No. 18 Sheet No. 10 A. At Detail 5/10, change the dimension from 2' -8" to 8 ", 2' -4" to 7" and 5' -0" to 1' -3 ". Tigard ES Remodel and Tualatin ES Remodel Addendum No. 1, Page 3 of 5 Project No. 9523/9524 Item No. 19 Sheet No. P2 A. At General Notes, add the following: "3. Temporarily disconnect lavatories in rooms M15A and M15 to allow for new wainscot and floor installation. Re- connect fixtures after the aforementioned installation. Coordinate with other trades." Item No. 20 Sheet No. No. P3 A. At General Notes, add the following: "3. Temporarily disconnect existing fixtures which are to remain in room M20 to allow for new floor and wainscot installation. Re- connect fixtures after the aforementioned installation. Coordinate with other trades." B. At Drawing Notes, change note 11 to read: "Replace (E) flush valve with Sloan Model 186 -1 flush valve." Item No, 21 Sheet No. P4 A. At General Notes, add the following: "3. Temporarily disconnect existing fixtures which are to remain in room B12 to allow for new wainscot installation. Re- connect fixtures after the aforementioned installation. (E) floor mount urinals do not require removal. Coordinate with other trades." . B. At Drawing Notes, change note 13 to read: "Replace (E) flush valve with Sloan Model 186 -1 flush valve." Item No. 22 Sheet No. P5 A. At General Notes, add the following: "3. Temporarily disconnect existing fixtures which are to remain in rooms C15 and C16 to allow for new wainscot installation. Re- connect fixtures after the aforementioned installation. (E) floor mount urinals in room C16 do not require removal. Coordinate with other trades." B. At Drawing Notes, change note 1 to read: "Remove (E) flush valve from urinal. Provide (N) Sloan Model 186 -1 flush valve." Item No. 23 Sheet No. M1 A. At Drawing Notes, add the following to note 1: "Provide steam pressure sensor / controller upstream of the cabinet unit heater control valve. Provide seven -day day / night thermostat. Provide all control wiring, conduit, and other devices required to interface to manufacturer's controls and to accomplish the operating sequence stated in the specifications." Item No. 24 Sheet No. DE3 A. At Building "A" Electrical Demo Plan Lower Floor 1/DE1, Boys & Girls Rest Rooms, add existing light fixtures to be removed. Quantity and layout of existing light fixtures is similar to that of new light fixtures shown on Sheet E4. Item No. 25 Sheet No. El A. At Notes, change note 6 to read: "Stub up exterior of building and "LB" into building where indicated." Tigard ES Remodel and Tualatin ES Remodel Addendum No. 1, Page 4 of 5 Project No. 9523/9524 Item No. 26 Sheet No. E2 through E5 A. At General Notes, add the following: "See Architectural Sheets for reference to room names and numbers." Item No. 27 Sheet No. E4 A. At Library L4 Circulation Desk, provide 120V /20A connection to power pole identified by note 7. Home run to electrical panel N2 circuit 11, use spare circuit breaker. B At Classroom B6, change Mark WH/1 on north wall to WH/2. APPROVED SUBSTITUTIONS Item No. 28: The following is a list of material items and manufacturers other than those specified that are approved for bidding. All approved substitute items are subject to requirements of original specifications, drawings and any addenda: SECTION ITEM MANUFACTURER 08305 Access Door J.L. Industries, 24" x 30" Model PWE. 09680 Carpet Patchcraft "Einstein 28 Zeftron 2000 with interlock back. 10192 Cubical Tracks Imperial Fastener, IFC -98 with IFC -100 roller carrier. 16500 Light Fixture as shown on Drawings Light Fixture Type B Lithonia 2VRTF 2 32 VL 120 GEB Light Fixture Type C Hubbell SW42R -E1 Light Fixture Type J Hubbell RVL- 400H9 -C73 w /GK -22 Lithonia TWH 150S TB END OF ADDENDUM NO. 1 Tigard ES Remodel and Tualatin ES Remodel Addendum No. 1, Page 5 of 5