The URL can be used to link to this page

Home My WebLink About03043 - Technical Information Report - Geotechnical •_•- _ 'f _:.. _..._. .�;-.___':'._.. _,_. _ .._ .- .__.v_,. _.- i -:�� '_/ � - ". _ ' .� ' ' '4 _. ..._ � —� �''� _�_ :��=1 _ � l•• '_ - -..� v--- �` I �• .� GEOTECHNICAL ENGINEERING STUDY - - � �� : �_. - PROPOSED RESIDENTIAL DEVELOPMENT �� ' � 3716 NORTHEAST 12T" STREET `` RENTON, WASHINGTON _ �_Y = � _ �-�r � � _ �: ` E-9760 __ � �� ___ - _ -� � ' S.i.._ Y':._ �. . . _ } .:_ ' _ q�' - �x L ; �_ -.. .%'-�. _.+- .. � .. . _ . ..� j s _ t-:,��`�1�� _ �'� _ - � _ � _- � y �� - . . Y ��` ' - � �" . 1 � � � _ ---�� ._� - � ¢��`� � � j x ' 4 -� "'" _�i.� �� 7+ -.--_� " _ �. _ __ - - :.� a � y'� �'- y'' � � - ; � _ � � _". _ t _ .a.d - s�'��_ � �.�� ._` �. � � ��r�_ � ` .�� _ � ` -_ - �- � \ � _ ,. - �; - _ � � � � _ � ,� �. �_ .�� - ��.' _ j - _�- -= - — _ - \ �^ _ __ " j� � �-t-Y -3 .'- _ 3 � : �€ �� I � � � - � E _-� �., . �' ��. - �� _ - � ; . � } -.�__ • ' -_ F_'T- _ �._� -- �. .. _ _ _ _ . �z�:.'� _ . _ �=��` .�: ... = _ ' " _' � �'� � Y�� - �4~ r� � ' � � " F�rth COt�lSultarltS It�C. ��,� � ��.� „�' GYniChnic.dEn{;i�xr•rs.Geolo{y�tilslGii��iramk�nalPnrniltiiti ,�,� • �- - 30�3 ,�G,.��,,�,�-� zr GEOTECHNICAL ENGINEERING STUDY I PROPOSED RESIDENTIAL DEVELOPMENT �, 3716 NORTHEAST 12T" STREET ' RENTON, WASHlNGTON E-9760 August 6, 2001 PREPARED FOR KBS I I, LLC ,. . P�ARjF ; ��,`~��c,�f wqSy! ��•y" � �a � � � .� - a ;; � ^ � o ;., 1? I v� z �. , ! x 2 .�� ', r ,:� Kris .E. ��o� ', Pro'ec ana er � EXPVRES 02-09-D3 I - � yle R. Campbell, P.E. Manager of Geotechnical Services Earth Consultants, Inc. � 1805 - 136th Place Northeast, Suite 201 �ellevue, Washington 98005 (425) 643-3780 Toll Free 1-888-739-6670 � IMPORTANT INFORMATION ABOUT YOUR GEOTECHNiCAL ENGINEERING REPORT More construction problems are caused by site subsur- technical engineers who then render an opinion about face conditions than any other factor. As troublesome as overall subsurface conditions, their likely reaction to subsurface problems can be. their frequency and extent proposed construction activity, and appropriate founda- have been lessened considerably in recent years, due in tion design. Even under optimal circumstances actual large measure to programs and publications of ASFE/ conditions may differ from those inferred to exist, The Association of Engineering Firms Practicing in because no geotechnicai engineer, no matter how the Geosciences. qualified, and no subsurface exploration program, no The follov.�ing suggestions and observations are offered matter how comprehensive, can reveai what is hidden by earth, rock and time. The actual interface between mate- to help you reduce the geotechnical-related delays. rials may be far more gradual or abrupt than a report cost-overruns and other costly headaches that can indicates. Actuaf conditions in areas not sampled may occur during a construction project. differ from predictions. Nothing can be done to prevent the unanticipated, but steps can be taken to help minimize their A GEOTECHNICAL ENGINEERING impact. For this reason, most experienced owners retain their REPORT IS BASED ON A UNIQUE SET 9eotechnical consultants through the consiruction stage, to iden- tify variances, conduct additional tests which may be OF PROJECT-SPECIFIC FACTORS needed,and to recommend solutions to problems encountered on site. A geotechnical engineering report is based on a subsur- face exploration plan designed to incorporate a unique SUBSURFACE CONDITIONS set of project-specific factors.These typically include: the general nature of the structure involved, its size and CAN CHANGE configuration; the location of the structure on the site and its orientacion; physical concomitants such as Subsurface conditions may be modified by constantly- access roads, parking lots, and underground utilities, changing natural forces. Because a geotechnical engi- and the level of additional risk which the client assumed neering report is based on conditions which existed at by virtue of limitations imposed upon the exploratory the time of subsurface ezploration,construction decisions program. To help avoid costly problems,consult the s►iould nnt he based on a geotechnical engineering report whose geotechnical engineer to determine how any factors adequacy may have heen a�ected by time. Speak with the geo- which change subsequent to the date of the report may technical consultant to learn if additional tests are affect its recommendations. advisable before construction starts. Unless your consulting geotechnical engineer indicates Construction operations at or adjacent to the site and otherwis2, your geotechnical engineering report should not natural events such as floods,earthquakes or ground- be used: water fluctuations may also affect subsurface conditions •When the nature of the proposed structure is and. thus, the continuing adequacy of a geotechnical changed. for example, if an office building will be report.The geotechnical engineer should be kept erected instead of a parking garage, or if a refriger- apprised of any such events,and should be consulted to ated warehouse will be built instead of an unre- determine if additional tests are necessary. � frigerated one: •when the size or configuration of the proposed GEOTECHNICAL SERVICES ARE structure�s altered: PERFORMED FOR SPECIFIC PURPOSES •when the location or orientation of the proposed AND PERSONS structure is modified: •when there is a change of ownership.or Geotechnical engineers' reports are prepared to meet •for application to an adjacent site. the specific needs of specific individuals.A report pre- Geotechnical engineers caxnot accept responsibilitu/or p.ohlems pareci for a consuiting civil engineer may not be ade- which may develop iJ they are not consulted a�ter factors consid- quate for a construction contractor, or even some other ered in their report's deveiopment have chanqed. consulting civil engineer. Unless indicated o[herwise. this report was prepared expressly for the client involved and expressly for purposes indicated by;he dient. Use MOST GEOTECHNICAL "FINDINGS" by any other persons for any purpose,or by the client ARE PROFESS[ONAL ESTIMATES for a different purpose, may result in problems. No indi- j vidual other than the client should apply this report/or its Site exploration identifies actual subsurface conditions intended purpose without hrst conferring with the geotechnical only at those points where samples are taken,when engineer. No persnn should apply this report(or any purpose they are taken. Data derived through sampling and sub- other than that originally contemplated without�irst conferring sequent laboratory testing are extrapolated by geo- with the geotechnical engineer. � A GFATECHNICAL ENGINEERING der the mistaken impression that simply disdaiming re- REPORT IS SUBJECT TO sponsibility for the accuracy of subsurface information always insulates them from attendant liability. Providing MISINTERPRETATION the best available information to contractors helps pre- Costly problems can occur when other design profes- �ent costly construction problems and the adversarial sionals develop their plans based on misinterpretations atcitudes which aggravate them to disproportionate � of a geotechnical engineering report.To help avoid scale. . these problems, the geotechnical engineer should be �AD RESPONSIBILITY retained to work with other appropriate design profes- -j sionals to explain relevant geotechnical findings and to CLAUSES CLOSELY ] review the adequacy of their plans and specifications relative to geotechnical issues. Because geotechnical engineering is based extensively on judgment and opinion, it is far less exact than other � design disciplines.This situation has resulted in wholly unwarranted daims being lodged against geotechnicaf ' I BORING LOGS SHOULD NOT BE consultants. To help prevent this problem, geotechnical engineers have developed model clauses for use in writ- SEPARATED FROM THE ten vansmittals. These are not excuipatory dauses � I ENGINEERING REPORT designed to foist geotechnical engineers' liabilities onto '' someone else. Rather, they are definitive clauses which Final boring logs are developed by geotechnical engi- identify where geotechnical engineers' responsibilities neers based upon their interpretation of field logs begin and end. Their use helps all parties involved rec- lassembled by site personnell and laboratory evaluation ognize their individual responsibilities and take appro- of field samples. Only final boring logs customarily are �riate action. Some of these definitive dauses are likely � included in geotechnical engineering reports.These logs to appear in your geotechnical engineering report, and should hot under any circumstances be redrawn for inclusion in you are encouraged to read them closely. Your geo- architectural or other design drawings. because drafters technical engineer will be pleased to give full and frank may commit errors or omissions in the transfer process. answers to your questions. � Althou�h photographic reproduction eliminates this problem, it does nothing to minimize the possibility of OTHER STEPS YOU CAN TAKE TO contractors misinterpreting the logs during bid prepara- -� tion. when this occurs,delays,disputes and unantici- REDUCE RISK pated costs are the all-toafrequent result. Your consulting geotechnical engineer will be pleased to To minimize the likelihood of boring log misinterpreta- discuss other techniques which can be employed to mit- tion,give contractors ready access to the complete geotechnical igate risk. In addition,ASFE has developed a variety of � engineering report prepared or authorized for their use. materials which may be beneficial. Contact ASFE for a Those who do not provide such access may proceed un- complimentary copy of iu publications directory. � .� � ,.j I ',I � Pub(ished by l � THE ASSOCIATION � OF ENGINEERING FIRMS I PRACTICING IN THE GEOSCIENCES 8811 Colesrille Road/Suite G 106/Silver Spring, Maryland 20910/(301) 565-2733 �, I0788/3M . I'� L-_ � .,- " ��,� ��'��"�� `�'�� Eartl� Consulta��ts Inc. �M� I \,'�� ' ''�,,,�,�i',,�., . (e•nir��hni<�al I�.ny�in��•n.G�,dny;al�R I�.m�iruron�•in�d tii I�•nu�l� �ril�� "�� '�� I August 6, 2001 E-9760 KBS III, LLC 12505 Bel-Red Road Bellevue, Washington 98005 Attention: Mr. Curtis Schuster Dear Mr. Schuster: We are pleased to submit our report titled "Geotechnical Engineering Study, Proposed Residential Development, 3716 Northeast 12`h Street, Renton, Washington". This report presents the results of our field exploration, selective laboratory tests, and engineering analyses. Based on the results of our study, it is our opinion the project can be constructed generally as planned. Support of the residences may be provided using conventional , spread and continuous foundation systems bearing on competent native soils or on structural fill used to modify site grades. Slab-on-grade floors may be similarly supported. We appreciate this opportunity to be of service to you. If you have any questions or if we can be of further assistance, please call. Respectfully submitted, EARTH CONSULTANTS, INC. ��%�� Kristina M. Weller, P.E. Project Manager KMW/KR�me 1805-13oth Piac�N.E.,Suite 201,Bellevue,Washington 98005 Bellevue(425)643-3780 FAX(425)746-0860 Toll Free(888)739-0670 I TABLE OF CONTENTS E-9760 PAGE INTRODUCTION ................................................................................................... 1 Ge nera I ........................................................................................................... ProjectDescription .......................................................................................... 1 SITE CONDITIONS ................................................................................................ � 1 Surface ........................................................................................................... Subsurface ...................................................................................................... � Groundwater ................................................................................................... I 2 LaboratoryTesting ........................................................................................... 3 ' DISCUSSION AND RECOMMENDATIONS................................................................ 3 , General ........................................................................................................... ' 3 Site Preparation and General Earthwork .............................................................. 3 Foundations..................................................................................................... Retaininq and Foundation Walls ......................................................................... 6 Slab-on-Grade Floors ........................................................................................ I 7 Seismic Design Considerations........................................................................... �� 7 Excavations and Slopes .................................................................................... 8 Site Drainage ................................................................................................... ' 9 Utility Support and Backfill ................................................................................ 10 PavementAreas..................................................................••--•--...................... 10 LIMITATIONS ....................................................................................................... 11 AdditionalServices........................................................................................... 11 APPENDICES Appendix A Field Exploration '�, Appendix B Laboratory Test Results ILLUSTRATIONS ' Pfate 1 Vicinity Map , Plate 2 Test Pit Location Plan ' Plate 3 Typical Footing Subdrain Detail Plate 4 Utility Trench Backfill ' Plate A 1 Legend Plates A2 through A7 Test Pit Logs Plate B1 Grain Size Analyses Earth Consultants, Inc. GEOTECHNICAL ENGINEERING STUDY PROPOSED RESIDENTIAL DEVELOPMENT 3716 NORTHEAST 12'�" STREET RENTON, WASHINGTON E-9760 INTRODUCTI�N General ' This report presents the results of the geotechnical engineering study completed by Earth Consultants, Inc. (ECI) for the proposed Residential Development in Renton, Washington. The general location of the site is shown on the Vicinity Map, Plate 1 . The purpose of ' this study was to explore the subsurface conditions at the site and based on the conditions encountered to develop geotechnical recommendations for the proposed site development. Project Description We understand it is planned to develop the site with a single-family residential development with and access street. We have previously provided infiltration recommendation for the site in our letter dated July 26, 2001 . At the time our study was performed, the site, proposed building locations, and our exploratory locations were approximately as shown on the Test Pit Location Plan, Plate 2. The proposed development will include asphalt-surfaced parking and driveway areas. We anticipate traffic will consist of passenger vehicles and occasional service and delivery trucks. If the above design criteria are incorrect or change, we should be consulted to review the recommendations contained in this report. In any case, ECI should be retained to perform a general review of thz final design. SITE CONDITIONS Surface The subject site is located at 3716 Northeast 12th Street (see Plate 1 , Vicinity Map). The site is approximately rectangular in shape, extending about 220 feet in the east-west direction and 185 feet in the north-south direction. Earth Consultants, Inc. - GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 2 Subsurface Subsurface conditions were evaluated by excavating six test pits at the approximate locations shown on Plate 2. Piease refer to the Test Pit Logs, Plates A2 through A7, for a more detailed description of the conditions encountered at each location expiored. A description of the field exploration methods is included in Appendix A. The following is a generalized description of the subsurface conditions encountered. Our test pits indicate the site is immediately underlain by a one to four inch thick layer of topsoil and rootmass. This soil unit is characterized by its brown to black color and the presence of organic material. Th�s soil layer is not considered suitable for use in support of foundations, slabs-on-grade, or pavements. In addition, it is not suitable for use as a structural fill, nor should it be mixed with material to be used as structural fill. Underlying the topsoil in Test Pit TP-1 and TP-6, we encountered one and one half to four feet of fill. The fill consisted of inedium dense brown silty sand with gravel with some organics and wood pieces (Unified Classification SM). The native soils in Test Pit TP-1, TP-2, TP-3, and TP-5 consisted of inedium dense to very dense silty sand with gravel (Unified Classification SM). In Test Pit TP-2 a layer of poorly graded sand with silt (SP-SM) was encountered from two to four and one half feet below grade. The native soils in Test Pit TP-4 consisted of inedium dense poorly graded sand with silt (SP-SM). In Test Pit TP-6 we encountered four feet of silty sand underlain by poorly graded gravel (GP). Groundwater Groundwater seepage was not encountered in our test pits, however mottling of the soils was encountered at two to five feet below the ground surface. A perched groundwater condition may be present in the winter months above the very dense silty sand layer. The contractor should be made aware that groundwater is not static. There will be fluctuations in the level depending on the season, amount of rainfall, surface water runoff, and other factors. Generally, the water level is higher and seepage rate is greater in the wetter winter months (typically October through May}. � Earth Consultants, Ina GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 3 Laboratory Testing Laboratory tests were conducted on several representative soil samples to verify or modify the field soil ciassification and to evaluate the general physical properties and engineering characteristics of the soil encountered. Visual field classifications were supplemented by grain size anafyses on representative soil samples. Moisture content tests were performed on all samples. The results of laboratory tests performed on specific samples are provided either at the appropriate sample depth on the individual boring logs or on a separate data sheet contained in Appendix B. It is important to note that these test results may not accurately represent the overall in-situ soil conditions. Our geotechnical recommendations are based on our interpretation of these test results and their use in guiding our engineering judgment. ECI cannot be responsible for the interpretation of these data by others. In accordance with our Standard Fee Schedule and General Conditions, the soil samples for this project will be discarded after a period of fifteen days following completion of this report unless we are otherwise directed in writing. � DISCUSSION AND RECOMMENDATIONS General Based on the results of our study, it is our opinion the proposed development can be constructed generally as planned. Support of the residences may be provided using conventional spread and continuous foundation systems bearing on competent native soils or on structural fill used to modify site grades. Slab-on-grade floors may be similarly ` supported. This report has been prepared for specific application to this project only and in a manner consistent with that level of care and skill ordinarily exercised by other members of the profession currently practicing under similar conditions in this a�ea for the exclusive use of KBS III, LLC, and their representatives. No warranty, expressed or implied, is made. This report, in its entirety, should be included in the project contract documents for the information of the contractor. Site Preparation and General Earthwork Based on the preliminary site plan, it appears site grading will consist of grading the site to provide level lots, installing underground utilities and grading the roadway. Earth Consultants, Inc. GEOTECHNICAL ENGINEERING STUDY KBS Ill, LLC E-9760 August 6, 2001 Page 4 The building and pavement areas should be stripped and cleared of foundations, surface vegetation, organic matter, and other deleterious material. Existing utility pipes to be abandoned should be plugged or removed so that they do not provide a conduit for water and cause soil saturation and stability problems. Based on the thickness of the topsoil layer, encountered at our test pit locations, we estimate a stripping depth of six inches. Stripped materials should not be mixed with materials to be used as structural fill. Following the stripping, the ground surface where structural fill, foundations, or slabs are to be placed should be observed by a representative of ECI. Proofrolling may be necessary in order to identify soft or unstable areas. Proofrolling should be performed under the observation of a representative of ECI. Soil in loose or soft areas, if recompacted and still yielding, should be overexcavated and replaced with structural fill to a depth that will provide a stable base beneath the general structural fitl. The optional use of a geotextile fabric placed directly on the overexcavated surface may help to bridge unstable areas. The soils encountered during the site exploration are moisture sensitive due to their high fines content. As such, in an exposed condition, they will become disturbed from normal construction activity, especially when in a wet or saturated condition. Once disturbed, in a wet condition, they will be unsuitable for support of foundations, slabs or pavements. Therefore, during construction where these soils are exposed and will support new structures, care must be exercised not to disturb their condition. Consideration should be given to placement of rock or other methods to protect exposed native, undisturbed soils that will support foundations or new structural fill. If disturbed conditions develop, the affected soils must be removed and replaced with structural fill. The depth of removal will be dependent on the level of disturbance developed during construction. Given the above, a summer earthwork schedule is recommended. Structural fill is defined as compacted fill placed under buildings, roadways, slabs, pavements, or other load-bearing areas. Structural fill under floor slabs and footings should be placed in horizontal lifts not exceeding twelve (12) inches in loose thickness and compacted to a minimum of 90 percent of its laboratory maximum dry density determined in accordance with ASTM Test Designation D-1557-91 (Modified Proctor►. ' The fill materials should be placed at or near their optimum moisture content. Fill under pavements and walks should also be placed in horizontal lifts and compacted to 90 ' percent of maximum density except for the top twelve (12) inches which should be compacted to 95 percent of maximum density. Earth Consultants, Inc. GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 5 During dry weather, most soils which are compactible and non-organic can be used as structural fill. Based on the results of our laboratory tests, the existing soil at the time of our exploration appears to near the optimum moisture content and should be suitable for use in its present condition as structural fill, provided the grading operations are conducted during dry weather. Based on laboratory testing, the soil has between 4 and 33 percent fines passing the No. 200 sieve. Soil with fines in the upper part of this range will degrade if exposed to excessive moisture, and compaction and grading will be difficult if the soil moisture increases significantly above its optimum condition. If the native soil is exposed to moisture and cannot be compacted then it may be necessary to import a soil which can be compacted. During dry weather, most non- organic compactible soil with a maximum particle size of six inches can be used. Fill for use during wet weather should consist of a fairly well graded granular material having a maximum particle size of six inches and no more than 5 percent fines passing the No. 200 sieve based on the minus 3/4-inch fraction. A contingency in the earthwork budget should be included for this possibility. Foundations Based on the results of our study, it is our opinion the proposed residences may be supported on a conventional spread and continuous footing foundation bearing on competent native soil or on structural fill used to modify site grades. For frost protection considerations, exterior foundation elements should be placed at a minimum depth of eighteen (18} inches below final exterior grade. Interior spread foundations can be placed at a minimum depth of twelve (12} inches below the top of slab, except in unheated areas, where interior foundation elements should be founded at a minimum depth of eighteen (18) inches. With foundation support obtained as described, for design, an allowable bearing capacity of two thousand five hundred i2,500) pounds per square foot (psf) for structural fill or competent native soil can be used. Continuous and individual spread footings should have minimum widths of eighteen (18) and twenty-four (24) inches, respectively. Loading of this magnitude would be provided with a theoretical factor-of-safety in excess ! of three against actual shear failure. For short-term dynamic loading conditions, a one- third increase in the above allowable bearing capacities can be used. With structural loading as expected, total settlement in the range of one inch is anticipated with differential movement of about one-half inch. Most of the anticipated settlements should occur during construction as dead loads are applied. Earth Consultants, Inc. GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 6 Horizontal loads can be resisted by friction between the base of the foundation and the � suppoRing soii and by passive soil pressure acting on the face of the buried portion of the foundation. For the latter, the foundation must be poured "neat" against the competent native soils or backfilled with structural fill. For frictional capacity, a coefficient of .40 can be used. For passive earth pressure, the available resistance can be computed using an equivalent fluid pressure of three hundred fifty (350) pounds per cubic foot (pcf). These lateral resistance values are allowable values, a factor-of-safety of 1 .5 has been included. As movement of the foundation element is required to mobilize full passive resistance, the passive resistance should be neglected if such movement is not acceptable. Footing excavations should be observed by a representative of ECI, prior to placing forms or rebar, to verify that conditions are as anticipated in this report. Retaining and Foundation Walls Retaining walls and foundation walls that act as retaining walls should be designed to resist lateral earth pressures imposed by the retained soils. Walls that are designed to I yield can be designed to resist the lateral earth pressures imposed by an equivalent fluid with a unit weight of thirty-five (35) pcf. If walls are to be restrained at the top from free movement, the equivalent fluid weight should be increased to fifty (50) pcf. These values are based on horizontal backfill and that surcharges due to backfill slopes, hydrostatic pressures, traffic, structural loads or other surcharge loads will not act on the wall. If such surcharges are to apply, they should be added to the above design lateral pressure. The passive pressure and friction coefficients previously provided in the Foundations section is applicable to retaining walls. If design against earthquake loading is desired, a rectangular pressure distribution equal to six times the wall height {6H) should be added to the above lateral earth pressure values. In order to reduce the potential for hydrostatic forces building up behind the walls, retaining walls should be backfilled with a suitable free-draining material extending at least eighteen (18) inches behind the wall. The remainder of the backfill should consist of structural fill. The free-draining backfill should conform to the WSDOT specification for gravel backfill for walls (WSDOT 9-03.12(2)). A perforated drainpipe should be placed at the base of the wall and should be surrounded by a minimum of one cubic foot per lineat foot with three-eighths inch pea gravel. Earth Consultants, Inc. i � � -- GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 7 Slab-on-Grade Floors Slab-on-grade floors may be supported on competent native soil subgrade or on structural fill. Disturbed subgrade soil must either be recompacted or replaced with structural fill. Concrete slabs resting on soil ultimately cause the moisture content of the underlying soils to rise. This results from continued capillary rise and the ending of normal evapotranspiration. As concrete is permeable, moisture will eventually penetrate the slab resulting in a condition commonly known as a "wet slab" and poor adhesion of floor coverings. Therefore if slab moisture is a concern, the slab should be provided with a minimum of four inches of free-draining sand or gravel. In areas where slab moisture is undesirable, a vapor barrier such as a 6-mil plastic membrane may be placed beneath the slab. Two inches of damp sand may be placed over the membrane for protection during construction and to aid in curing of the concrete. Seismic Design Considerations The Puget Lowland is classified as a Seismic Zone 3 in the 1997 Uniform Building Code (UBC). Earthquakes occur in the Puget Lowland with regularity, however, the majority of these events are of such low magnitude they are not detected without instruments. Large earthquakes do occur, as indicated by the 1949, 7.1 magnitude earthquake in the Olympia area and the 1965, 6.5 magnitude earthquake in the Midway area. There are three potential geologic hazards associated with a strong motion seismic event at this site: ground rupture, liquefaction, and ground motion response. Ground Rupture: The strongest earthquakes in the Puget Lowland are widespread, subcrustal events, ranging in depth from thirty (301 to fifty-five (55) miles. Surface faulting from these deep events has not been documented to date. Therefore, it is our opinion, that the risk of ground rupture during a strong motion seismic event is negligible. Earth Consultants, Ina GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 8 Liquefaction: Liquefaction is a phenomenon in which soils lose all shear strength for short periods of time during an earthquake. Groundshaking of sufficient duration results in the loss of grain to grain contact and rapid increase in pore water pressure, causing the soil to behave as a fluid. To have a potential for liquefaction, a soil must be cohesionless with a grain size distribution of a specified range (generally sands and silt); it must be loose to medium dense; it must be below the groundwater table; and it must be subject to sufficient magnitude and duration of groundshaking. The effects of liquefaction may be large total and/or differential settlement for structures founded in the liquefying soils. Based on the density of the site soils, it is our opinion the potential for liquefaction over the site during a seismic event is negfigible. Ground Motion Response: In accordance with Table 16-J of the 1 997 UBC, soil type Sc should be used in design. Excavations and Slopes The following information is provided solely as a service to our client. Under no circumstances should this information be interpreted to mean that ECI is assuming responsibility for construction site safety or the contractor's activities; such responsibility I is not being implied and should not be inferred. ! In no case should excavation slopes be greater than the limits specified in local, state and II Federal safety regulations. Based on the information obtained from our field exploration ' and laboratory testing, the medium dense sand and gravel would be classified as Type C � by OSHA. Temporary cuts greater than four feet in height in Type C soils should be ' sloped at an inclination of 1 .5H:1 V {Horizontal:Vertical). The very dense silty sand soil ' � would be classified as Type A by OSHA. In Type A soils temporary cuts greater than four feet in height can be steepened to 3/4H:1 V. If slopes of this inclination, or flatter, cannot be constructed, temporary shoring may be necessary. Shoring will help protect against slope or excavation collapse, and will provide protection to workers in the excavation. If temporary shoring is required, we will be available to , provide shoring design criteria. Permanent cut and fill slopes should be incfined no steeper than 2H:1 V. Cut slopes should be observed by ECI during excavation to verify that conditions are as anticipated. Supplementary recommendations can then be developed, if needed, to improve stability, including flattening of slopes or installation of surface or subsurface drains. In any case, water should not be allowed to flow uncontrolled over the top of slopes. Earth Consultants, Inc. � _ GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 9 Permanently exposed slopes should be seeded with an appropriate species of vegetation to reduce erosion and improve stability of the surficial layer of soil. Site Drainage Groundwater seepage was not encountered in our test pits, however mottling of the soils was encountered. Seepage may be encountered above the very dense silty sand in the winter months. If seepage is encountered in foundation or grade beam excavations during construction, the bottom of the excavation should be sloped to one or more shallow sump pits. The collected water can then be pumped from these pits to a positive and permanent discharge, such as a nearby storm drain. Depending on the magnitude of such seepage, it may also be necessary to interconnect the sump pits by a system of connector trenches. The appropriate locations of subsurface drains, if needed, should be established during grading operations by ECI's representative at which time the seepage areas, if present, may be more clearly defined. During construction, the site must be graded such that surface water is directed off the site. Water must not be allowed to stand in areas where buildings, slabs or pavements are to be constructed. Loose surfaces should be sealed at night by compacting the ' surface to reduce the potential for moisture infiltration into the soils. Final site grades must allow for drainage away from the building foundations. The ground should be sloped at a gradient of 3 percent for a distance of at least ten feet away from the build- ings, except in paved areas, which can be sloped at a gradient of 2 percent. Footing drains should be installed around the building perimeters, at or just below the invert of the footing, with a gradient sufficient to initiate flow. A typical detail is provided on Plate 3. Under no circumstances should roof downspout drain lines be connected to the footing ', drain system. Roof downspouts must be separately tightlined to discharge. Cleanouts �, should be installed at strategic locations to allow for periodic maintenance of the footing �, drain and downspout tightline systems. �I Earth Consultants, Inc. GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 10 Utility Support and Backfill Based on the soil conditions encountered, the soils expected to be exposed by utility excavations should provide adequate support for utilities. Utility trench backfill is a primary concern in reducing the potential for settlement along utility alignments, particularly in pavement areas. It is important that each section of utility line be adequately supported in the bedding material. The material should be hand tamped to ensure support is provided around the pipe haunches. Fill should be carefully placed and hand tamped to about twelve inches above the crown of the pipe before heavy compaction equipment is brought into use. The remainder of the trench backfill should be placed in lifts having a loose thickness of less than twelve inches. A typical trench backfill section and compaction requirements for load supporting and non-load supporting areas is presented on Plate 4. Pavement Areas The adequacy of site pavements is related in part to the condition of the underlying subgrade. To provide a properly prepared subgrade for pavements, the subgrade should be treated and prepared as described in the Site Preparation section of this report. This means at least the top twelve (12) inches of the subgrade should be compacted to 95 percent of the maximum dry density {per ASTM D-1 557-91). It is possible that some localized areas of soft, wet or unstable subgrade may still exist after this process. Therefore, a greater thickness of structural fill or crushed rock may be needed to stabilize these localized areas. The following pavement section can be used for lightly-loaded areas (car traffic}: ll • Two inches of asphalt concrete (AC) over four inches of crushed rock base (CRB} material, or • Two inches of AC over three inches of asphalt treated base (ATB) material. Heavier truck-traffic areas will require thicker sections depending upon site usage, pavement life and site traffic. We will be pleased to assist in developing appropriate pavement sections for heavy traffic zones, if needed. Earth Consultants, Inc. GEOTECHNICAL ENGINEERING STUDY KBS III, LLC E-9760 August 6, 2001 Page 11 Pavement materials should conform to WSDOT specifications. The use of a Class B asphalt mix is suggested. LIMITATIONS Our recommendations and conclusions are based on the site materials observed, selective laboratory testing and engineering analyses, the design information provided us, and our experience and engineering judgment. The conclusions and recommendations are professional opinions derived in a manner consistent with that level of care and skill ordinarily exercised by other members of the profession currently practicing under similar conditions in this area. No warranty is expressed or implied. The recommendations submitted in this report are based upon the data obtained from the test pits. Soil and groundwater conditions between test pits may vary from those encountered. The nature and extent of variations between our exploratory locations may not become evident until construction. If variations do appear, ECI should be requested to reevaluate the recommendations of this report and to modify or verify them in writing prior to proceeding with the construction. Additional Services As the geotechnical engineer of record, ECI should be retained to perform a general review of the final design and specifications to verify that the earthwork and foundation recommendations have been properly interpreted and implemented in the design and in the construction specifications. ECI should also be retained to provide geotechnical services during construction. This is to observe compliance with the design concepts, specifications or recommendations and to allow design changes in the event subsurface conditions differ from those anticipated prior to the start of construction. We do not accept responsibility for the performance of the foundation or earthwork unless we are retained to review the construction drawings and specifications, and to provide construction observation and testing services. Earth Consultants, Ina ,I —_ c ' .='r ," � ' � � ++IlAGs �_`��.. r..�. �c; �'-�r�'t�.�-�M� " -�N 1 - ��, � _ f i � ; . . � �, � •�� •- � ,�si,� �J� �` ,.- .,� i� � P� 4'y ,� ( p �v,hq.� l � � � � � 1� �i}+:ST ?/ • � °'��. '.�_ � r.�) t� f �C - i �al- ��' 1 � ' SC 91ST� 57' -NIY � ° % �:* +..,N�J �r, ,.1 �i �T ;,I y�„I_��. ;CI�kK �S� � c �Z��..J^ SE j i 7+.►1[► �� i - 3 '?:�: � �� ' '..i.. l�.%i"� �l` jS{j� �`.'�� `' Ol$� 'i� li � -'J`,`f :E Y �- � ". ;,,� .+�_ - I __� � �`�'S. ki N{ _ F t�: . -' _ � - .� Cn i . f ' i �� ti �-�-�-t � _. � s f. c&`e""�'?ti�` L R1€'� - }�--� X _� $tL�. .�. . �-��'1 r . �P�',.�. .� ' . i � ;� � �� i ��p�:.... � � r: �.. �.::_ y5�f;�_ �i - �=�� T��f►� -�Fr �- 3.. i y " "',� �,r..�..�c-`- r_ i'�'_-=�L�^ I — -�-�. _- _i�e,+,�l- . 1 .� i _�.t.r-..��rYl 1�� '�'Z� t I �� s .�. s� '�� t .- �Y�� } . ._. �. _�� 'r�� Sr : � . � .�� —'r v�� '`i •,. r_ �'"' - -_" �� x;�-, + �`L �T:}- ` SIEFv.'� ( .� �` _ i ,; � `� -�`_'�_I f�� ` � i s �� ..,.' �` .. e s :;1 � fi�`Ifft �,.� � -� � ";;t' , -s '�'=— F#�5: — :� G_ �„'�+ 'C: e '�i �p' � '�Y�rt ` � �5�. :ni�w yT � -- � STH 1'l _�l,_T11 C.I + S._ �� r � � _ __^`�J( J - � � �E� J ��1M71t � ��M1 � .�` �� r ii- � � ��''{:�� =u ^� 'G "-�� . IQOTN W k'� � 'sE �i:i�Qell �'!Y � } �� . . > .�� .�� v� w. a�D� �tDI- `I �� ,. , �. � ;• '�f � lt ,� Ki SE �' lf.'•7c.'i� ��lE� � . !. i I�I 1�� S� � �- �i _ I� � _ - 'Z�i � V ��+ �' Lf�^3( i a � � � �� a� � � - 2ao p[, � a � ��t � �� I�� + � �� ST�:a � : o > A ?.31E�Si a � .� x'i � -' 9� ;i � � �;_ r „� r � � 4��,r ".i � �.i K � R �Si � ! � � c � Q� �,��. �� I� � � �t�,� ,� � � � � , � �r� Y�� .��_ � � _ I � �k� u, � _ � ac �c �af� �. � � yf 1'3T �'- t`�� -�'T��r: , �.._ ��{ �" �� .. i .at ;� �� w x 0�� » � . .� i �at Ff �' �'� R ` ! �;_�S"i�y4� _` —�� 7�E - aA �. � a� Y i SC ;Q`_•TY_ � � _ ♦ 4 :r��:+� �. - Y1� u � x�aX;,1S'S�f' Y r^ '`` �'�u �_�' : _ S�-t �•• � � , �, �, -� � ;vxeFx � �� . '�, -{�'1,* �yTi�*I=�S' i[.1: � �a �. '�-- .-� � 'C�ft �t f �n > > I i '-� !E L�7�1- .`� •r.-�+n a ifl?7� i i � "+� � .�O t.�R �r . � � Si �. * r :M -~ 4= u� . } i�=��hi� �j �t ti�� '':�'�, � :r�_ rY� y� •1� - t�• i � � � � � litli � �7r� ` �- 6 �tim Rl � } ��' :�,; r ' ` T�, � y iaa .� v �� - � � , � ( �-' �� . � � ! � � � SS1H Si IJ 1�'� -�1 --� � {) ^� �'I^ �U4 �t+ a a- � ^t�1�— �� .�' � � �L � ��_'=f; � � �'�� _``$ I ,, � NE 1 _2TH �� 5T � � T � " ;1,:i L,� ti��'��i Y �`�n' 'E �- tt�'�}?�"--- ST i`AO � �„� f?' , s� ��A I� � �k;d:n s7 - e ,,_�_ � ��-� f � I �� r � 4r ap* ~i �� iw s1�+ 1 �F iz � =j [eIY9R x �" v ��. , � � x N! i2Tn .St x iin � , R1.�i � � .jr �� _ f�IL�I� O,: ��Cr � I ♦ r_' ��3 I � . +ry�� `` ' t� `' �-" ■ 1 - `.j�': �� ~ . � �= 1 � Z _'f'. 1/ Ci�stzcnQ� � iE !6Tj^ h•+r�� r _ � .. . a R. �� { _ .. �. t t �� i - tv .T,• L� ' _�� .� Y � f v ltic `T�i7}d Q11 � � � G ':�J:1. � - ' j I �y •Q� X; IC i ,11 � ' ' ' - - .1t1tO _ r� ea�� Q1N R � ' �� i~� , � ' :� 11a"�� I L g < •-i � � �r% ft � -, . � � e,..., y, � �` aE t�� f ? . �-�; �� 'L — �a�}-j S� � �y G� 4� � � - '��+,�.R�1�{k�.^S 4TI1 ��-� =`N ` ,� t� Q'11 ST .yr �• ��-- � � r� . c3s �A.�il� � ' .. . 1.. ^ _ . f ! y __,� ,'Y--. .y � # +�'� �_ `� � .. K��:^ '.-�� J . . .'� ` �vr j ,�Yt�¢� ��'� ,r �l�t 81H SX. �A:�t � � SI : : ��. I� 'I �� X� :: c!�#� ,t` '�5�� F �I _iT�$ 4T� �� i2� �. �j n�� Fy3�DE L�i '� �� w ��^'�--'Z��`-'�'��4'� - '��+• ? �I � � .��t j[' � 3' �?.:', � z-�SEYI��`_^91p �c .`"'�x,` �` ��7►� ' f� ; � w` t� � � +Ni� _.� {I �1 1c � � II �' :�� . � 1._. `�."� st -- ��: _. , a ; i Reterence: Eal'trl COIISUltaI7tS, IIIC. Puget Sound Area Georechnical Engineers.Gedogists�Envrrnmen�al Scien�is�s i King County/Map 626 , By Thomas Brothers Maps Vicinity Map � ; Dated 2001 3716 N.E. 12th Renton, Washington NOTE: This plate may contain areas of color. ! ECI cannot be responsible for any subsequent Drwn. GLS Date July 2001 Proj. No. 9760 � � misinterpretation of the information resul�ng ( from black 8� white reproductions of this plate. ��ed RDP Date 7/26/01 Plate 1 � � i - — ----— - -- --- -- - - - - i I I I —■— �TP-4 —:— TP-3� i I - il I � ; � _� I TP-2 I� � ! � TP-5 I � i _-_ ' i � _._ � � TP-1 �TP-6 —.— I I � I - - -- - -- - --- - - -- - - - - - - - - I Gj�� tis�� f G�C�� ' I LEGEND TP-1-i-Approximate Location of Approximate Scale ECI Test Pit, Proj. No. 0 20 4o sott. ; E-9760, J u ly 200 7 ! Subject Site � Earth Consultants, lT1C. Geaechrtical Engineers.Geologis`s&Envarnmemal SciernLs�s i Test Pit Location Plan � 3716 N.E. 12th Renton, Washington NOTE: This plate may contain areas of color. ECI cannot be responsible for any subsequent Drvm. GLS Date July 2001 Proj. No. 9760 misinterpretation of the information resulting � from bladc 8� white reproductions of this plate. Checked RDP Date 7/26/01 Plate 2 0 . o .a . �_ Slope To Drain . o ,_ . o ,•o - - ; o :-. . e . ,:: .. , . - o - o • -o - •��-o 6 inch min. .' �o-� 0 � �: o o , �— o� o � � :o'�� .e�-' '� � ' , �` o ae _ ':::"o� .:'.o.' :.o ;oe4:. :�•._e:�o:.��: -; ; °: 18 inch min. :o;;' _'.�e.;o;• -�_ - :,,�.-:o - .e o �•� �o -•• _ •'>� �� ,�o• o ` �o p .�� 4 inch min. ,�`� '° .�� •� �'��.;� ";�'• ,� e�o� °- �� • _,• " .o_.• :• . . - eo Diameter ��e:.: -;".' ,:o'�;:. ;•. � � .o - _ � o . � Perforated Pipe—� _ •` :..�.�°�-;"' �°'-_. _, ,o 00 0 0, o o 'o 0 _:• ; . .o o °o o e Wrapped in Drainage ��. _ :.•:.� �: � ` � • � o � "'�` I .r 0.' , o Fabric ._ '. ~ - ' � `_"�' °. :o o � o � ,, ,• .o�' I i I 2 inch min. 2 inch min. / 4 inch max. I-.--12 inch min. SCHEMATIC ONLY - NOT TO SCALE NOT A CONSTRUCTION DRAWING LEGEND � Surface seal; native soil or other low permeability material. Fine aggregaie for Portland Cement Concrete; Section 9-03.1(2) of the --�'��':' WSDOT Specifications. ODrain pipe; perforated or slotted rigid PVC pipe laid with perforations or sfots facing down;tight jointed; with a positive gradient. Do not use flexible corrugated plastic pipe. Do not tie building downspout drains into footing lines. Wrap with Mirafi 140 Filter Fabric or equivalent. ''� � '�` TYPICAL FOO7ING SUBDRAIN DETAIL j' I .'!i', F..arth Consultants Inc. 3716 N.E. 12th ��',�1 '�� ;'!i' c`b"`""'�'�'�.,r`�.`�s�,.s`�""n""x"'�s�"'� Renton, Washington Proj. No. 9 760 Drwn. GLS Date Aug. O1' Checked RDp Date 8/8/O1 Plate 3 Non-Load Supporting Floor Slab or Areas Roadway Areas , ;,., . .,..�. ;� �4JAj - ;�L._ •t.r�ac - - ' o ° � ' � � o Varies �^uo°a 9�"j o " o. 0 p o O 8J . 95 1 Foot Minimum Backfill , 80 90 , Varies , o.�` ., PIPE o. 0 0 :.; :o. ..�00 a0,o'° ••o. 0 4'0,� �. •n•��.OD , o�..Q�.o .�. ''o U e 40. b•s�-OaQ.O•'�. • �O�. . Bedding o'o•O°..�e:Da:• o�'p'o°�d. :�q Vdf12S o' o o. o••po.. O.".o0�00.. 00. . o o.• o•'�• o ' uQp�Q..�_p�o.•0.��.- p'o:o':. o. 'p .o.•. �, o. o p �.. pO.O:.00O:��o�:�8.'.00 O, o..�Qp••�odQ'o �. 0'0 p.• O. po��O'a O. .00o. �•o Q eo. .D�,•o�',J�p Q� ./l�/,•pOuO•d•'.Oa O.O,po � l/ LEGEND: :,:_-� ;�,,=�":�:-�=_;y�:�. Asphalt or Concrete Pavement or Concrete Floor Slab :•;St�K_'��^��:;J` o� ° ��'O - o , � o • Base Material or Base Rock � BackfiN; Compacted On-Site Soil or Imported Select Fill Material as Described in the Site Preparation of the General Earthwork Section of the Attached Report Text. 95 Minimum Percentage of Maximum Laboratory Dry Density as Determined by ASTM Test Method D 1557-91 (Modified Proctor), Unless Otherwise Specified in the Attached Report Text. Bedding Material; Material Type Depends on Type of Pipe and �°:0.0°000� LaYing Conditions. Bedding Should Conform to the Manufacturers Recommendations for the Type ofi Pipe Selected. , � TYPICAL UTIUTY TRENCH FILL ((' � , Earth Consultants InC. 3��6 N.E. 12 th . . i 1 ,I 1 �e�ctvucal Enqlrxrs_Grc�p}ys a Fn�irtrmwnrd Scxn��s Renton, Washington Proj. No. 9760 Drwn. GLS Date Aug. Ol' Checked RDP Date g/g/pl Plate 4 ' APPENDIX A FIELD EXPLORATION E-9760 Our field exploration was performed on July 2, 2001 . Subsurface conditions at the site were explored by excavating six test pits to a maximum depth of eight feet below the existing grade. The test pits were excavated by Northwest Excavating subcontracted to ECI, using a trackhoe. Approximate test it locations were determined b p y pacing from site features. The locations of the test pits shouid be considered accurate only to the degree impiied by the method used. These approximate locations are shown on the Test Pit Location Plan, Plate 2. The field exploration was continuously monitored by a engineer from our firm who classified the soils encountered, maintained a log of each test pit, obtained representative samples, measured groundwater levels, and observed pertinent site features. Samples were visually classified in accordance with the Unified Soil Classification System which is presented on Plate A1, Legend. Representative soil samples were placed in closed � containers and returned to our laboratory for further examination and testing. 'i Test Pit Logs are presented on Plates A2 through A7. The final logs represent our 'I interpretations of the field logs and the results of the laboratory tests of field samples. The stratification lines on the logs represent the approximate boundaries between soil types. In actuality, the transitions may be more gradual. The consistency of the soil shown on the logs was estimated based on the effort required to excavate the soil, the stability of the trench waals, and other factors. � , �J I t_ � , ,-,--�� Earth Consultants, Inc. � � i� MAJOR DIVISIONS GRAPH LETTER TYPICAL DESCRIPTION SYMBOL SYMBOL � ('j�/ Wel�-Graded Gravels, Gravel-Sand Andve� Clean G�avels � e� � � gW Mixtures, Little Or No Fines Gravelly (little or no fines) r ` � GP Poorly-Gradetl Glavels.Gravel- Coarse Sods GraineC � � � • � • 9p Sand Mixtures, Little Or No Fines Soils More Than (�j(� Silty Gravels,Gravel-Sand- SOqo Coarse Gravels With gm Silt Mixtures Fraction Fines(appreciable Reta�ned On amount of tines 1 GC Clayey Gravels.Gravel-Sand- No. 4 Sieve gC Clay Mixtures Sand �e oo 'e S�l�l Wel�-Graded Sands, Gravelly And Clean Santl o � o o SW Sands. Lit[le Or No Fines Sandy 1 little or no tines � ; � ; More Than : " " SP Poorly-Graded Sands, Gravelly 50% Matenal Soils �� ::o�°A :; Sp Sands, Little Or No Fines Larger Than More Than E No. 200 S�eve SD°6 Coarse f SM Silty Sands, Sand- Silt Mixtures Size Sands With c SRl Fraction F�nes(appreclable S eveng No.4 amount of fines. ,� � SC SC Ciayey Sands, Sand-Clay Mixtures � M L Inorganic Siits d Very Fine Sands,Rock Flo�r,Silty- rp� Clayey Fine Sands;Clayey Sitts w/Slight Plasticfty Fine Silts Liquid Limit � CL Inorganic Clays Of Low To Medium Plasticity, Gra�ned �d Less Than 50 � C� Gravelly Ctays, Sandy Clays, Silty Clays. Lean Soils Clays 1 I I QL Organic Silts And Organic I � I � I � O� Silty Clays Of Low Plast�city MH Inorganic Silts, Micaceous Or Diatomaceous Fire More Than mh Sand Or Silty Soils 50 k Mater�al Silts Smaller Tran And Liquid Limit CH Inorgartic Ctays Of High No.200 Sieve Clays Greater Than 50 Cfl Plasticity, Fal Clays. Size ��/�� OH Organic Clays Ot Medium To High Ofi Plasticity, Organic Silts `��' `��' `t�' pT Peai, Humus, Swamp Soils Hlghly Organic Soils �, ��i, ��, ��i Pt W ith High Organic Contents Topsoii �y�'y y� Humus And Duff Layer Fill Hiyhly Variable Constituents The discussion in the text of this report is necessary for a proper understanding of the nature of the material presertted in the attached logs. DUAL SYMBOLS me used to indicate borderline aoil classficadion. C TORVANE READING,tsf T 2'O.D. SPLIT SPOON SAMPLER qu PENETROMETEA READING,tsf � W MOISTURE, %dry weight � 24' I.D. RING OR SNELBY TUBE SAMPLER P SAMPLER PUSHED � ' SAMPLE NOT RECOVERED ' WATER OBSERVATION WELL pcf DRY DENSITY,Ibs. per cubic ft. LL LJQUID L1MIT,% Q DEPTH OF ENCOUNTERED GROUNDWATER PI PLASTIC INDIX DURING IXCAVATION I SUBSEQUENT GROUNDWATER LEl/EL W/DATE � � �� LEGEND '` �� ' EartjZ Consultants Inc. i;;,� ', i;" �._!;I,' �` II '�1 � '�^I,�� (R�M<iItlINWI:II�(IIM<'f].�111It�blS61'JI\'YIMMIM111.1ISCllYllpl� �j '�' �' Proj. No. 9760 Date July O1' Plate �1 Test Pit Log Projed Name: Sheet of 3716-N.E. 12th 1 1 Job No. Logged by: Date: Test Pit No.: 9760 RDP 7/2/01 TP-1 Exca�ration Contador: Ground SurFace Elevation: NW E�acavatin Notes: General w `—' $ � � u� o Surface Conditions: Depth of Topsoil &Sod 1"-2" Notes (%) '° �- p 11 � � E. � N � � SM Brown silty SAND witt�gravel, medium dense, moist(Fill} i -trace or anics 2 SM Red brown silty SAND with gravel, medium dense, moist 11.0 3 s.� 4 -becomes very dense, glacial till 5 6 -becomes brown gray s.7 7 -33%fines 8 Test pit terminated at 8.0 feet below e�asting grade. No groundwater I encountered dunng e�acavation. NOTES: Test pits e�¢;avated by NW Excavating using a CASE 9010B track mounted e�ac:avator. s m � ^ � 0 � U W � o Test Pit Log � Ec`�I`Crl COI1SUItaT�1tS Ir1C. 3716- N.E. 12th � p C�cxttY�nical Fn¢Inraas.C�0.v��FnNmnnx�nrnl SCImtL+� r Renton,Washington a W Proj.No. 9760 Dwn. GLS Date July 2001 Chedced RDP Date 7/26/01 Plate A2 . � Subsurface cond'itions depided represent our observations at the time and loqtion of this e�loratory hole,modified by engineering tests,anafysis and judgmenL They are not necessarily representative of other times and locations.We qnnot accept responsibility for the use or interpretation by others of i..fi....�fltinn�vucen4u�rv�lhic IM Test Pit Log , Prqeci Name: Sheet of 3716- N.E. 12th 1 1 Job No. La,�ged by: Date: Test Pit No.: 9760 RDP 7/2/01 Tp-2 Excavation Contactor. Ground Surface Elevation: NW E�acavatin Naes: „ o t �, N o Surface condaions: Depth of Topsoil 8�Sod 1"-2" General �N Ndes (%) 1O E. p " m � i. C➢ u� cn �n SM Red brown silty SAND with gravel, medium dense, moist, trace organics � 13.5 5.t - 2 SP-SM Brown poorly graded SAND with silt and gravel, medium dense to o dense, moist 0 � 3 0 4 -9%fines o ° 5 SM Brown gray silty SAND with gravel, very dense, moist, trace mottling s 8.9 � 8 Test pit terminated at 8.0 feet below e�asting grade. No groundwater encountered during excavation. 0 � N H � � U w � a m � Test Pit Log � Earth Consultants Inc. 3716-N.E. 12th OC�rt.'tmkalFngl�xx�.G-twc�2ts514Fnvlm�n�cnra!tickn� Renton, Washington f- a � w Proj.No. 9760 D�m. GLS Date July 2001 Chedced RDP �ate 7/26101 Plate A3 Subsurface condrtioas depicted represerrt our observations at the time and location of this e�loratory hole,modified by engineering tests,�alysis and judgmerri. They are nat necessariy representafrve of other times and locations.We cannot accept responsibility for the use a interpretation by others of irri.r....�{'v�n�veen�My1 M Ih:c Lv� Test Pit Log Projed Name: Sheet of 3716- N.E. 12th 1 1 Job No. Logged by: Date: Test Pit No.: 9760 RDP 7l2/01 TP-3 Ezr,avation Contador Ground Surface Ele�ration: NW E�acavatin Notes: General W `—' $ t m cn o Surface Conditions: Depttt of Topsoil 8�Sod 2"-4" Notes (^/,) '� E. o `� m � E. � � � � SM Brown silty SAND with gravel, medium dense, moist, trace organics 3.9 � �.& 2 SM Becomes brown to gray silty SAND with gravel, very dense, moist, trace mottling 3 4 89 5 6 Test pit terminated at 6.0 feet below e�sting grade. No groundwater encountered during e�a:avation. s � c � � 0 c� U w 'a m Test Pit Log m(� Earth Consultants Inc. 3716-N.E. 12th O GexM�Avikal F�hr.as,Cw-c�lc�tiv�6 FnvlmnnxYual�c'k.niL+T � Renton,Washington � a r W Proj.No. 9760 Dwn. GLS Date July 2001 Chedced RDP Date 7/26/O1 P�ate A4 Subsurfaoe cond'Rions depided represent our observ�ations at the time and location of this e�loratory hole,modified by engineering tests,analysis and judgmerrt. They are not necessanly representafnre af other times and locations.We cannot accept responsibility for the use or iMerpretation by others of �.,s.....,�.:,,.,...�e.,,a.+.,..�ti:�w. Test Pit Log Projed Name: Sheet of 3716- N.E. 12th 1 1 Job No. Logged by: Date: Tesi Pit No.: 97fi0 RDP 7/2101 TP-4 F�acavation Contacior: Ground Surfaoe Elevation: NW E�acavatin Naes: �e�l w � � r m � o Surface condaions: Depth of Topsoil &Sod 2"-4" Naes �%} `��° r g " � � T C� cn cn t� SM Brown silty SAND with gravel, medium dense, moist, trace organics � 6.0 - Z SP-SM Brown poorly graded SAND with silt and gravel, medium dense, moist 2.s � 0 0 3 0 o ° 4 0 � ` 5 4.7 � 6 0 0 7 4.5 0 , 8 Test pit terminated at 8.0 feet below e�asting grade. No groundwater encountered dunng e�a;ava6on. e ' � � � 0 �, U W � o Test Pit Log - �(� Earth Consultants Inc. 3716-N.E. 12th O CRx�r�ctvilral FYi{yrxns.Gc�bElv_+&FiMrc�nK:nrN SCYr.n�tv� F Renton, Washington a . w Prq.No. 9760 own. GLS Date July 2001 Chedced RDP D�e 7/26/01 P�ate A5 Subsurface conditions de�icted represent our observ�ations at the time and location of this e�loratory hde,modified by engineerirtg tests,analysis and ', judgment They are nd necessarily representative of other times and locatio�s.We cannot accept responsbility for the use or intetpretation by others of I .,s.v..,��.,...,.�a.,�a.+,,.,,ti��i.,.. I Test Pit Log Projed Name: Sheet of 3716-N.E. 12th 1 1 Job No. Logged by Date: Test Pd No.: 9760 RDP 7/2/01 TP-5 Ewcavation Contador Ground Surface Elevation: NW F�acavatin Ndes: � o � m � o Surface Conditions: Depth of Topsoil 8�Sod 2"-4" C'�eneral w L a n a �e$ ��p� � T Q LL 10 � >. (,7 fn fn [/� SM Brown silty SAND with gravel, medium dense, moist, trace organics 3.8 � s.s 2 SM Brown and gray silty SAND with gravel, dense to very dense, moist, trace mottling 3 ' 4 5 fi -becomes gray 7 8.5 8 Test pit terminated at 8.0 feet below e�asting grade. No groundwater encountered during excavation. �, I � s m c � 0 � U W --� i a m Test Pit Log W Earth Consultants Inc. 3716-N.E. 12th 8 G�xMr.cYmlralFnghrey&G-�kMltt+&Fnvfrtnnr.rcallctrntl� Renton, Washington � a � , � Prq.►�o. 9760 Dwn. GLS Da�e July 2001 Cnedced RDP Date 7/26/01 Plate A6 Subsurface conditions depic�ed represent our�bservations at the t�nne and lor.ation oF this e�loratory hde,modified by engineering tests,analysis and )udymenc. l7,ey are not necessariy representa2n+e or ocner times and�«�t;ons.we cannoc accept respons;bi�ity for a,e use or interpretacion by ar,ers or 7nf....r�a!"vv..rncnn►di iv.11.ic I.v. __ _ Test Pit Log Projed Name: Sheet of 3716- N.E. 12th 1 1 Job No. Loc�ed by: Date: Test Pit No.: 9760 RDP 712/01 TP� E�acav�ation Contador: Ground Surface Elevation: NW E�a;avatin Notes: � o L „ � o surface c«,daions: Depth of Topsoil 8�Sod 1"-2" Ger,era� w Notes ("/,) '� E. p " m � E. � � � � SM Brown silty SAND with gravel, medium dense, moist, trace organics, wood debris(Fill) �0.6 � 2 3 �o.s . � , 4 GP Brown poorly graded GRAVEL with sand, dense to very dense, moist, w trace mottling •. • 5 •'• • 6 •• � -4%fines •�• 7 12.1 • •• • • • 8 Test pit terminated at 8.0 feet below ebsting grade. No groundwater I encountered during excavation. e N n H Q v U W a � Test Pit Log WC� Earth Consultants Inc. 3�,s-rv.E. ,Zth O C�r.ctimKal Fnglr�s,Gr�Mcxthn6 Frnlrnnnxwnl ti�k�nrt� r Renton,Washington a � F Proj.No. 9760 Dwn. GLS Date July 2001 Chedced RDP Date 7/26/01 �ate A7 Subsurface conditions depicted represent our observations at the 6me and location of this e�loratory hole,modified by engineering tests,analysis and judgment. They are not r�cessariy representati�e of other times and locations.We cannot accept responsibility for the use or interpretation by oth�s of inFMn7/iM MK`M/dl M N�K`IM . � � � • � . • • : • � � . . . • � � : . • � : : . . . . . : : . .. .a ti,� �� .� - - �_ �_ _ , . — __a, „ .�� _ -�� . -a�== . ., ��__ .a �� _ . - � � - �, .� e e--== _ � @ � ■� �_ . . :, � ,, o_ . ri �� , ' � � � E' ;_ '` � :..:_ C, _.— �—�_ . . � � �C: �� C�'�C�'� ' � .. �CC , , �C� � � _.� C �C � C� E �.� ' �C .. �� .�� ■. � � � � �• ■ �� . _� �� e5��, � � _ ., =� 5 Ci— : `� � � � .� �� Dy i�� u ` ��C' �� ■� ._.��.... � �. � � C - . � , �:�C�:� :C�� _ � i� " �� , . . ��C�' � �_.�� .�� CC . .. ��_�.�. �a-� E . . . , .� Q� 'C � C.� � � � ,.: C�� ., _�=�e: � �_ .. � �■� �� 0 C C � �� C.� � �:CC� ��:�_--: �-� 8.��_ • � -- —��.. ,;_� m � .. . � 8 �C� �� a�=� ' — —.--.E�,_ -�i - — �� 0��: � C�:o C C .�� a � =C� , CC C . � � ��CO � C� � :, c _� 5.�� , �-�-� � 9� ��_ �S � �: -� -, � —� �, �5� a • °�== ; , C� 9 ��og��.�, ,�' .0 �� • . � � _ = C � �_... E■_ _�__C :� �� _� _ __.s� � ., . __ - �E ..0 �� :' �� C ��.�C ,. . , � � . .��:��-�E�6� ..,..�e_.5 . . . . .:_ • � �� . ' � �� • �� ' ' � �• '� m� _ ,. . . , • • � . � � � . ; . � . � . � . ■ ' i . ... . - , DISTRIBUTION E-9760 4 Copies KBS III, LLC 12505 Bei-Red Road Bellevue, Washington 98005 Attention: Mr. Curtis Schuster Earth Consultants, Inc.