The URL can be used to link to this page

Home My WebLink About02859 - Technical Information Report - Geotechnical ��' � - .::.., �` " .:> s s� :.: r '� �,r: . . i:3'::::s� . �% �3 7.;3 GEOTECHNICAL REPORT ! {, Garry Marshall Property i NE 4th Street and 138th Avenue SE , Renton, Washington � Project No. T-3472-6 '� � - �- $s� � ' _ ��..:�.�.�� _ �; �� r �, �, ��::� Y�„� � ��`k� �� Terra Associates, Inc. , { ��.;� �. , � � , ;. . � �� • ..z�,x.....,�. .�.,�,,.. � .3� $ ;, �_ ��. =�0�''`�;�1T PL^,P:,.;�;� ,...'" r ' Ci7Y OF RE�"JT�;V �, ,: ,>< ; ; MAR 12 1��9 �?�� .�-� .3... .. ..,_ . .• ._._.....,-. ' ' Prepared for: � � � � � � � R kon Develo ments Y p Seattle, Washing#on _..: � :,�.-:; i February 25, 1999 . , _ , .. ,. . . .. . ..- � ,Z��9 - = TERRA ASSOC IATES, I nc. �', Consultants in Geotechnical Engineering, Geoiogy ' and Environmental Earth Sciences ' February 25, 1999 Project No. T-3472-6 Mr. Wes Giesbrecht Rykon Developments 603 Stewart Street, Suite 919 Seattle, Washington 98101 Subject: Geotechnical Report Garry Marshall Property NE 4th Street and 138th Avenue SE Renton,`Vashington Dear Mr. Giesbrecht: As requested, we have conducted a geotechnical engineering study for the subject project. The attached report � presents our findings and recommendations for the geotechnical aspects of the anticipated project design and construction. The soils we observed during our subsurface investigation generally consisted of up to three feet of weathered glacial till overlying very dense unweathered glacial till. Loose to medium dense recessional outwash silty sand ��vas found overlying the glacial till in the northern portion of the site. Light to moderate groundwater seepage was observed in our test holes at depths ranging from 1.0 to 7.5 feet. Based on our study, it is our opinion that the site is suitable for consh-uction of the proposed buildings and access driveways. The structures may be supported on conventional spread footings placed directly on competent native soils, or on compacted structural fill placed on these soils. Roadways, driveway pavements, and floor slabs may be similarly supported. The on-site organic-free soils will be suitable for use as structural fill material,provided their moisture content can be controlled during construction during the summer months. During wet weather, import materials will be required. 12525 Willows Road, Suite 101 , Kirkland, Washington 98034 Phone (425) 821-7777 • Fax (42��i 821-4334 • terra@terra-associates.com Mr. Wes Giesbrecht February 25, 1999 VVe appreciate the opportunity to be of service during this phase of the project. We trust the information presented is sufficient for your current needs. If you have any questions or require additional information,please call. Sincerely yours, TERRA ASSOCIATES,INC. ,� �- �5�� . �u� � Maher A. Shebl,P.E. .�,,��' ��"�� Staff Engineer �'�� Q Anil Butail,P.E. �7ppy President �rsrst�9 QNAL MAS/AB:ts ex�tgE� 12;9/ �' cc: Mr. Ror��oTdy,Bush oe � rtc mgs � Project No. T-3472-6 Page No. ii TABLE OF CONTENTS I PaQe No. 1.0 Project Description......................................................................................................... 1 2.0 Scope of Work................................................................................................................ 1 3.0 Site Conditions............................................................................................................... 2 3.1 Surface............................................................................................................... 2 3.2 Soils................................................................................................................... 3 3.3 Groundwater...................................................................................................... 3 3.4 Seismic Considerations..................................................................................... 3 4.0 Discussion and Recommendations.................................................................................4 4.1 General..............................................................................................................4 4.2 Site Preparation and Grading ............................................................................4 4.3 Excavations ....................................................................................................... 6 4.4 Foundations....................................................................................................... 6 4.� Slab-on-Grade Floors........................................................................................ 7 4.6 Detention Pond.................................................................................................. 7 ; 4.7 Drainage............................................................................................................ 8 4.8 Driveway and Parking Area Pavements............................................................ 8 4.9 Utilities.............................................................................................................. 9 5.0 Additional Services ........................................................................................................ 9 6.0 Limitations...................................................................................................................... 9 Fiaures VicinityMap.......................................................................................................................Figure 1 ExplorationLocation Plan..................................................................................................Figure 2 Typical Footing Drain Detail..............................................................................................Figure 3 Appendix Field Exploration and Laboratory Testing....................................................................Appendix A (i) Geotechnical Report Garry Marshall Property NE 4th Street and 138th Avenue SE Renton, Washington 1.0 PROJECT DESCRIPTION The project will consist of developing an approximately 5.7-acre site located near the south«�estern corner of the intersection of NE 4th Street and 138th Avenue SE in Renton. The location of the project site is shown on the Vicinity Map,Figure l. We were provided with a preliminary site plan prepared by Bush Roed & Hitchings, dated December 1, 1998. The preliminary site plan shows the project consisting of the construction of 13 storage buildings and a retail store with associated parking and driveways. Access to the property will be from a main entrance off NE 4th Street. Emergency access will lead into the �vestern edge of the site from 138th A��enue SE. The retail store building «�ill be constructed in the northern portion of the site, �vest of the main entrance. Paved parking will be provided south of the retail store and north of the gated storage buildings. We anticipate the buildings will be lightweight structures with slab-on-grade floors. Building loads are expected to range from one to two kips per foot along load-bearing walls. We understand stormwater will be routed to detention facilities located in the southern portion of the site. Finish floor elevations and proposed grades are not avaitable at this time. Due to the relatively flat nature of the site, we anticipate that only minor grading will be required to establish final site elevations. The recommendations contained in the follo��-ing sections of this report are based on our understanding of the above preliminary design features. If actual features vary, or changes are made, we should be informed and requested to review them and amend or supplement our recommendations as required. We should review the final design drawings and construction specifications to verify that our recommendations have been properly interpreted and incorporated into project design and construction. 2.0 SCOPE OF V4'ORI� `�'e excavated 12 bacl:hoe test pits at the site to depths ranging from 9.5 to 11.0 feet below e�isting surface grades. Using the information obtained from our subsurface exploration, �ve performed analyses to develop geotechnical recommendations for project design and construction. February 25, 1999 Project No. T-3472-6 Specifically, this report addresses the following: • Soil and groundwater conditions • Site preparation and grading • Excavations • Foundation support • Slab-on-grade floors • Detention pond � Drainage • Driveway and parking area pavements • Utilities 3.0 SITE CONDITIONS 3.1 Surface The site is bound to the east by a retail business and undeveloped property. A restaurant, single-family residence, and 138th Avenue SE bound the site to the west. The site is bordered on the north and south by NE 4th Street and single-family residences, respectively. We gained site access from an asphalt driveway leading to the site from 138th Avenue SE. The majority of the site is flat. An approximately two-foot deep, four- to six-foot wide drainage ditch runs north-south along the northeastern property line, turning easrivard to drain into a wetland area in the eastern portion of the site. We noted shallow standing water within the ditch at the time of our field study. Standing water was also observed in a wetland area in the western portion of the site. The northern and central portions of the site are generally open, with vegetation consisting of wild grasses, scattered Scot's broom, and berry brambles. The eastern and westem portions of the site are primarily wooded with young to mature maple, cottonwood, and alder trees. Thick brush was also observed in these portions of the site. We noted occasional trash, including furniture and appliances, throughout the site. Page No. 2 February 25, 1999 Project No. T-3472-6 3.2 Soils Excavation of the test pits at the site revealed a 2- to 12-inch thick layer of topsoil or forest duff overlying glacially-derived silty sand soils. In Test Pits TP-6 through TP-8, and TP-10, the topsoil was underlain by recessional outwash silty sand soils to depths ranging from 2.0 to 6.5 feet. The recessional ourivash was loose in Test Pits TP-6, TP-7, and TP-10. In the remaining test pits, �veathered till consisting of loose to medium dense silty sand ��ith gravel and cobbles was found underlying the topsoil to depths of two to three feet. Dense to very dense glacial till or till-like soils were encountered beneath the �veathered till or recessional ourivash soils to the termination depths of each test pit. The glacial till consisted of silty fine to medium sand with gravel and cobbles. Occasional boulders were noted within the glacial till in Test Pit TP-9. The glacial till consisted of very dense silty gravel with sand in Test Pit TP-7. The Test Pit Logs in Appendix A present more detailed descriptions of the subsurface conditions encountered. The approximate test pit locations are shown on Figure 2. The Geologic Map of the Renton Quadrangle, King County, Washington, by D.R. Mullineaux, dated 1965, shows the soils at the site mapped as Quaterna.ry ground moraine deposits (glacial till). The on- site native silty sand with gravel and cobbles coi�elates with the mapped till soils. The silty medium sand observed in some of the test pits appeared to conelate with recessional ourivash mapped approximately one-half mile south of the site. 3.3 Groundw�ater We encountered groundwater in all of the test pits at depths ranging from 1.0 to 7.5 feet. In all test pits where the glacial till occurred at a shallow depth, light to moderate groundwater seepage was observed perched above the very dense glacial till. This type of groundwater occunence is typical for a glacial till site. The perched groundwater results from surface water infiltrating through the upper weathered till and outwash soils becoming perched on the underlying,relatively impervious glacial till. Very light to moderate ground�vater seepage was also observed in the test pits, emanating from sandy zones occurring within the glacial till. In general, the level and rate of ground�vater seepage at the site will vary,being at the highest level during the wet winter months. 3.4 Seismic Considerations The Puget Sound area falls within Seismic Zone 3, as classified by the Uniform Building Code (UBC). Based on the soil conditions encountered and the local geology, according to Table 16-J of the 1997 UBC,the site soil profile type S� should be used in the design of the structures. � Page No. 3 February 25, 1999 Project No. T-3472-6 �Ve reviewed the results of our field and laboratory testing in order to assess the potential for ', liquefaction of the site soils during a seismic event. Liquefaction is a phenomenon where there is a ' reduction or complete loss of strength in loose, saturated sands due to an increase in pore water pressure induced by vibrations from a seismic event. Due to the overall dense nature of the glacial till soils,we believe there is no risk of liquefaction-related impacts to the project. '� 4.0 DISCUSSION AND RECOMMENDATIONS 4.1 General Our subsurface exploration indicates the site is generally underlain by competent, glacially-derived soils. Accordingly,buildings constructed on the site may be supported on conventional spread footings placed on the competent, organic-free soils or on structural fill placed on these soils. Floor slabs and pavements may be similarly supported. Sorne of the surficial �veathereei till and recessional ourivash soi'_s are loose and exhibit l:igh moisture contents. In addition, construction will occur in the western portion of the site where groundwater was observed within the loose wet soils at a shallow depth. In building areas, it may be necessary to scarify and compact these loose,wet soils, or amend them with a cement additive prior to establishing building grades with compacted structural fill. Alternatively, it may be necessary to remove these loose soils and replace them with clean granular materials. The following sections provide recommendations regarding the above issues and other geotechnical design considerations. These recommendations should be incorporated into the final design drawings and construction specifications. 4Z Site Preparation and Grading To prepare the site for construction, all vegetation, organic surface soils, and other deleterious materials should be stripped and removed from the areas under construction. Surface stripping depths of 2 to 12 inches should be expected to remove the topsoil and forest duff. Organic soils will not be suitable for use as structural fill, but may be used for limited depths in non-structural areas. Cuts and fills can be made to establish finish grades once clearing and grubbing operations are completed. We recommend placing foundations, slabs, and pavement sections on undisturbed surfaces of competent nati��e soils, or suitably compacted structural fill placed on these soils. Page No. 4 February 25, 1999 Project No. T-3472-6 Prior to placing fill, a representative of Terra Associates should verify suitability of all exposed bearing soil surfaces to determine if any isolated soft and yielding areas are present. If excessively yielding areas are observed, they should be removed to a suitable subgrade and filled to grade with structural fill. In driveway and parking areas, if the depth of excavation to remove unstable soils is excessive, you may consider using a geotextile fabric, such as Mirafi SOOX or equivalent, in conjunction with structural fills in order to limit the depth of removal. Laboratory sieve analyses conducted on samples of the glacial till soils indicate they contain up to 26 percent by weight of fines (silt and clay particles). The high fines content will make these soils particularly sensitive to moisture conditions. Laboratory testing also indicates that the moisture contents of the site's soils were above optimum at the time of our study. These soils will not be suitable for use as structural fill in wet weather. In dry and warm weather, it may be feasible to use these soils as structural fill if their moisture contents can be controlled during construction. Some drying of the silty sand soils through aeration may be required to allow for suitable compaction. Because of their sensitivity to moisture, the silty sand soils at the site ��vill be susceptible to degradation if preparation of roadway, foundation, and slab areas occurs during wet weather. Where the silty sand is exposed at the footing subgrade elevation, it may be necessary to protect these areas with a layer of , lean mix or crushed rock. ' If grading is to be performed in wet weather, and it is necessary to import structural fill to the site, we recommend using a granular soil that meets the following grading requirements: U.S. Sie�e Size Percent Passing 3 inches 100 No.4 75 maximum No. 200 5 maximum* *Based on the 3/4-inch fraction. Prior to use, Terra Associates, Inc., should examine and test all materials proposed for use as structural fill. Structural fill should be placed in uniform loose layers not exceeding 12 inches and then compacted to a minimum of 95 percent of the soil's maximum dry density as determined by ASTM Test Designation D-698 (Standard Proctor). The moisture content of the soil at the time of compaction should be within two percent of its optimum, as determined by this ASTM standard. In non-structural areas or for backfill in utility trenches below a depth of 4 feet, the degree of compaction can be reduced to 90 percent. Structural fill compaction within City of Renton rights-of-way should be done in accordance with City standards. Page No. 5 February 25, 1999 Project No. T-3472-6 4.3 Excavations All excavations at the site associated with confined spaces, such as utility trenches and lower building levels, must be completed in accordance with local, State, or federal requirements. Based on current Occupational Safety Health Administration (OSHA) regulations, the very dense glacial till at the site would be classified as Group A soils. For temporary excavations more than four feet in depth ��ithin the very dense glacial till, the side slopes can be completed with a gradient of 0.75:1 (Horizontal:Vertical) or flatter. The medium dense recessional outwash silty sands would be classified as Group C soils. Excavations made within these soils should have side slopes no steeper than 1.5:1. If there is insufficient room to complete the excavations in this manner, you may need to consider using temporary shoring to support the excavations. Based on our investigation, there is a likelihood of encountering groundwater within excavations. The above recommended slope inclinations may need to be flattened at ]ocations where cut slopes intercept seepage zones. In addition, the need for dewatering should be anticipated during excavation. Groundwater seepage should be routed along diversion trenches to sump areas. It may be necessary to pump the water to temporary settling ponds for silt removal prior to directing it to a suitable outlet. The above information is provided solely for the benefit of the owner and other design consultants, and should not be construed to imply that Terra Associates assumes responsibility for job site safety. It is understood that job site safety is the sole responsibility of the project contractor. 4.4 Foundations Buildings may be supported on conventional spread foundations bearing on competent soils or on structural fills placed above competent soils. Foundation subgrades should be prepared and protected as recommended in the Site Preparation and Grading section of this report. Perimeter foundations should be at a minimum depth of 1.5 feet below final exterior grades for frost protection. Interior foundations may be constructed at any convenient depth below the floor slabs. We recommend designing foundations for a net allowable bearing capacity of 2,000 pounds per square foot (ps fl. For short-term loads, such as wind and seismic, a one-third increase in this allowable capacity may be used in structural design. With the anticipated loads and bearing stresses, total and differential building settlements should be less than one-half inch. Due to the granular nature of the soils, most of these settlements will occur during construction. Page No. 6 i ; February 25, 1999 Project No. T-3472-6 For designing foundations to resist lateral loads, a friction coefficient of 0.4 may be used for concrete ' poured directly on the till or outwash soils. Passive earth pressures acting on the sides of the footings may also be considered for resisting lateral design loads. We recommend calculating this lateral resistance using an equivalent fluid weight of 350 pounds per cubic foot (pc fl. At the perimeter foundation locations, we do not recommend including the upper 12 inches of soil in this computation because of the potential for disturbance from weather or future grading activity. The above passive resistance value assumes the foundations will be constructed neat against competent native soil or backfilled with structural fill as described in the Site Preparation and Grading section of this report. The recommended value includes a safety factar of 1.5. 4.5 Slab-on-Grade Floors Slabs-on-grade may be supported on the subgrade prepared and protected as recommended in the Site Preparation and Grading section of this report. We recommend placing a four-inch thick capillary break layer of free draining sand or gravel with less than three percent fines immediately below the floor slab. The capillary break material will reduce the potential for upward capillary movement of water through the underlying soil and subsequent wetting of the floor slab. Where moisture by vapor transmission is undesirable, a durable plastic membrane should be placed below the slab on top of the capillary break material. The membrane should be covered with two inches of clean,moist sand to protect against damage during construction and to aid in the curing of the concrete. 4.6 Detention Pond ` � Details of a possible detention pond are not known. It is likely that such a pond will be constructed ' primarily by excavation with only shallow berm fills expected. Based on the information obtained , from the test pits, it is likely that the pond bottom will extend into the glacial till soils. While design details are not available at this time, seepage conditions at the pond should be light to moderate ! occurring at the depth of the glacial till contact. The rate and volume of seepage is not expected to ', have any significant impact on the pond design storage volumes. A detailed geotechnical evaluation of �� - the pond should be conducted after the configuration has been finalized. I We recommend grading the interior pond slopes to a minimum slope inclination of 3:1. If fill berms are required, the fill should be keyed into competent native soils and compacted as a structural fill as described in the Site Preparation and Grading section of this report. Exterior slopes can be graded with a finished slope inclination of 2:1. Page No. 7 February 25, 1999 Project No. T-3472-6 4.7 Drainage Surface Final exterior grades should promote free and positive drainage away from the building areas at all times. Water must not be allowed to pond or collect adjacent to foundations or within the immediate building areas. With the exception of paved locations adjacent to buildings, we recommend providing a gradient of at least three percent for a minimum distance of ten feet from the building perimeters. At paved locations, a minimum gradient of one percent should be provided unless provisions are included for collection and disposal of surface water adjacent to the structures. Subsurface We recommend installing continuous drains along the outside lower edge of the perimeter foundations. Drainage should consist of a minimum four-inch diameter perforated pipe bedded on and backfilled with washed drain rock or pea gravel. The pipe should be placed with its invert equivalent to the elevation at the base of the adjacent footing. A typical foundation drainage detail is shown on Figure 3. The foundation drains and roof downspouts should be tightlined separately to an approved discharge facility. Subsurface drains must be laid with a gradient sufficient to promote positive flo�v to a controlled point of approved discharge. 4.8 Drivewav and Parking Area Pavements � Driveways and parking areas should be constructed on subgrades prepared as described in the Site Preparation and Grading section of this report. Regardless of the degree of relative compaction achieved, the subgrade must be firm and relatively unyielding before paving. The subgrade should be proofrolled with heavy construction equipment to verify this condition. With a properly prepared and stable subgrade,we recommend the following pavement sections: • Two inches of asphalt concrete (AC)over six inches of crushed rock base(CRB) • Two inches of AC over four inches of asphalt treated base (ATB) The paving materials used should conform to the Washington State Department of Transportation (WSDOT) specifications far Class B asphalt concrete,ATB, and CRB. Page No. 8 February 2�, 1999 Project No. T-3472-6 4.9 Utilities Utility pipes should be bedded and backfilled in accordance with American Public Works Association (APWA) or City of Renton specifications. As a minimum, trench backfill should be placed and compacted as structural fill as described in the Site Preparation and Grading section of this report. As noted, the silty sand soils excavated on-site are moisture-sensitive and will be difficult to use as backfill material in their present condition and during �vet weather. Therefore, moisture-conditioning will probably be necessary to facilitate proper compaction. If utility construction takes place during the w�inter season, you should be prepared to import suitable wet weather structural fill for use in utility trench backfilling. 5.0 ADDITIONAL SERVICES Terra Associates, Inc., should review the final design and specifications in order to verify that earthwork and foundation recommendations have been properly interpreted and incorporated into the project design and construction. We should also provide geotechnical services during construction in order to obsen�e compliance with the design concepts, specifications, and recommendations. This will also allow for design changes if subsurface conditions differ from those anticipated prior to the start of construction. 6.0 LIMITATIONS We prepared this report in accordance with generally accepted geotechnical engineering practices. This report is the property of Terra Associates, Inc., and is intended for specific application to the Garry Marshall Property project. This report is for the exclusive use of Rykon Developments, and their authorized representatives. No other warranty, expressed or implied, is made. The analyses and recommendations presented in this report are based on data obtained from the test pits excavated on-site. Variations in soil conditions can occur, the nature and extent of which may not become evident until construction. If variations appear evident, Terra Associates, Inc., should be requested to reevaluate the recommendarions in this report prior to proceeding with construction. Page No. 9 � 5T n 2 5T � '�.rQ �� '� <Er-`��+ lan� st � � a n 't =�� {��C'� � .�� 7I 2 II��, 1 � a . � � .^, �p�, ZA:O �� " a F� a t a I SF � � !/Y � � ' MnC ,p '.. ni � �� a ' �� 1 IMTM / '�. . o � • F'` . u�^Sr � �'^�`s z � 'tOtH ST & K � o�i SCTaM n ST � -� � '�, up c s .� a` �pf (REEK Y r � �/ � K f sT �y � J,`y OVL SPALE`_ S[I o5rn 5r �wE ��'�9TM•� � �� „ � 3� sE iasn� ri iosn� �,r�� . '�1+7N;' � u�oo �uw ny. � __a i v � vt SE`,�' ,r� \ � it �v��<' St �\ r +f'` v �+ ^ ia� ` �, SE � < SE 107TM �4( . � � z 1 6 q 1 # r� � u x � sc t a�n� v t� iorTx,,. � S i s��„ � �F I Q 6 s t� � r - �i P[fA � <' •aa:): EI \�:,,. � °� �'1 Y v0 .i -'le � � I i �_� �^i SE ,.g' �\ i z �_� �+[it�rx y y<i� .,\ < u�� ; ��' :d J,� _ �iN �.:.x,r vucfl . . 1�Fy� �.� � , x n� ro�<' � W +c��M sr � "w,�� :� ,pf < - �p3•� t 'aanrrr vurx Oy rt Y un n �� , � un� s-fe� �k.,' ` I w>caE r t� �'"rpN �S�PD�� 5E I�iTM r� -. . ST I NE 12TH `=� ST � K =im,' SE �� 112 ,`i�57 � I v um * SE 112?H 5T s, z o�� y i �v �., <��r �m � '� �...� • issou `s�9 R 3 �r�1 ��u�0 � tir n � �t�it• i�t�r.'~'sr '�t V aw1l'M ��} n Y�_. sE'W^lll'N�� (, D `�` ttra sr.Y um�. u 5 .E o � 1i.. '{*I < ST I ��,��. y � ��jjj xE\tl r`� � ��+ ''*r.d�� nr��on n� �R � � � I�� I■ x i�; i� S SE 11eTH ST c s �' .aa.s�` �f;` .c_o. Ye�-� �g �� +c torr'f�I:,� i�I � I < ! a 3 =�aTM �n SE � �[� `'�Jp '1_< NE M $T ' �T�*J« �^ii3�~ �iil�tl�� 5E 116ni S'I I:.U:t ''I16TH $T !I +'" � `\W -. �V; ��x,n� i[3 �I-�+ I SE 117iHST � i ■ i E < �9TH 5T n� �. l 3 c fi i � SE :19iH � ��S� � > $ i': ♦ `"►X!P RKz E' -� StYI IIB'w`�� „� _ +� _`� � -.19 k�. '�� o , ; � _ �� :� � �i. y _ 1 � `` �� _ ' = 10 � 1� �� MI ^: . _ � Y _� s. XEI BiH 5` `�wt 7n� �[ E, 8 wf ��m�n �i; ` SE 120tH :�� et 3 � BN t 1�.�� NE, 7TH $T 51�I MF R h� �T"�'� SE�1215T ST K . . z � n`' 1 � '.jE��312v0 ti �"` e= � � _ 50� �r�•� ".=�M1W u �i�lt ST 4-ST�� i�K AI St �, X � � �NE �a ' ♦ ^�` rt ' �� ' � . S � t 1'' �1!' o ME n `.., n Is`� z 7N �'l��Y . . .I � � '�_ �,.��,c �1� .�j. W -�. ��.,.Fy�,-; s�TM�^ _ a+a Sr y,_:'... _sE ttan�st sE tz�n� sr i a i MF .�'< r` �' �i�YME>� ''' NE SiH � � v� . sE t25rH 5r N T ' � s . t t ri <Hit 3�S-� > ,,,+ �r�.�,_ �t'z o`u, `,Ir� v!��\ si ��,� =s,�� C ` Y< , � � Q< SE I l56*N�N � '<I =1 �it�) � � � i / Y(�� a.Nfvr � � 0 . . -,-5- �`.-,1 �o � $� `� ll ` r wn�t rt �F��' < rc uc �"i X Y � - ��--�>.^_ v � �'�� e u � ,�, _; NE■ ��« � 4TH Z �� = SE 128TH S7 '" SE �� ^"'t .:�o a ,�v; ' i.aoo - -. 128TH _r- L � i �GRFE � .-. .. •<f• SE L29iH � ��h 1�W' �' � S _� & M RfAC _ NE JFD CT _ � Vl iS L �n� ••�I' � DARK r!� �r rsnv � sl <S(J W� �;,wrKt:�dt I SE. IJ1ST �.. / NE_ 2N0 ST �� i r � -,�'�� ; � � SE y" 5T SE I32ND ST 3100 � �_� - �� _ -- �8 y.I � SE 172�0.� crn c �s." s� �t( � 15 ��,� ' sc�nan cr v� � � � �i }'i`i!A � I �`7P Sf r� , �ff� �,� : � tr� � �� SITE �� =� ��= 16 E57�7ES 5c Sr ri Sf P �I Q �� hy ' ,.. .d� I757J� �]sn. < z �.a�L sr � 14 , se zxo-avi�l_ � s�_�� s¢ �5n�� `�-� � � � ��nr o s!� ��.,�.^_ ':d i � r--�s+co' - � Wi ' �I�<�� 4 p �r i i �i ±.i:: �!�'�"'Y, r ,�� . . �-L�� SE �'{ � � ,� —��{��'-N --. N ('--- � �� QL' y; „� �a�Q ' n Sf 1J8�x f` i iE IIBiN Vl t•+' � ot I x SE I �M �� .'.L .ze i�,rw vi ��`.q;:n SE U9TH Q � � �c SE SiN S �r�+'� �'�Dry ' ��Y N� PL �f S 1791H PL $�� r_Tb•+s� RD ��---�—,��, ;� ,—- —--J W � _ .� ,.,<M - t7vEw ��i�. Y k � a' ' U15T � '. _'��an n.�e� � �j �i �� SE 1�IST ..� , v� Y/ +�� 'St t__ 5�__s T sr� ei � � rl.i.in � sr 8 �r- f'��r,� � iaz+a sT= _se i.z.a s, + r �o se t�rw f, �j.�. ..:. L... � i S k 1 < � � !s� i�ro x �x � ^��, , 5E I�2w0 St i �4ti ( � ST r� �".'•� _ . �\:�� '" ��''rt i � /SFS�'y � d . � �.n ,r �_ ' ^ I E, f b Cf R : R7VfR S�,TH�.. ''i: n�vi� � � a- t�an�rx -�uST,:�_ f: ��ai - v�.�., „ S Q�'SE�1�JD : ST � n y: �t Sc A tun+ I N; `t'r _. _ � .. SJ., L_ � _ . a�7.�xi� zc—�/� o � "a�, ff�� dt +ts3oo=_ TURAL ZONE \ �.\•' cotF -—--—�-, _�y , ,'` ,�„� `�} =j ry� � -`�� , :�� MAP,LEWOOD `� �� x�� _�� o E . . y 1h x r n. ,=`�.� 9 f y`� �. 4�.w �y .. .. \ � � .!�. � �, ;j n = FL` t� � �/�� . � `b Q �aa SE .(. � ��'�a ., rF � 1 ,�fs i'iy-3� t�A o y S� �r '�' , ,'�.� t. , fF �-. CEQIH i'��\ �� p? �i � ¢ q � C - � �. t�� c. I� .�R� � i'RIYER� �. .�, y `; ' ,' � `y jf\�� ' �' . \,\\ ,i"� _ (i Rf��T�.. ZZ R/ R r 'FE61AWL_� ' � , J 6IiN \F4 ��M��_;t S}aY tt ��-� i.�� __�• 0� ,U.PC s.�`.,FA'PK r'�Q j ��NFS73�! r s[\�--- ytt i �j^ . `� si=.j •W _�_� rB C�r •� i��" ♦iD"y.� ✓5'�i J9 �/A �'Q_s` �1-• . �E ISI.7 xl tiW r y �,�' < r��M '� \ -I � �. y +•� �y/,sy T� � :\� : . .. a RD T w:t- , . �\ �a � �_ i- f � nar� a,�,��. . . i ;��,'% Ix - .._:i. tEAAR .s:,.Sr S r y�"sr �+TM,=--.-� .r y '�'Y .�'� �.�: c S f..._. _,�.�ILIVER,. .��..4 . itFr�m ( �'�'� �ir c` -�. -�- c�r:�_ ..l�+^P.Ub I'� �r�� ir,� � � I�aC °�na w� S!� �, a L,•'�J'� � �x'��'st�.54� �S7 L` •,e '. w.'��\, .��u��'' f .. r��''..� x'�.�u�n� s .. -r� ... REFERENCE: THE THOMAS GUIDE, KING COUMY, WASHINGTON, PAGES 626, 627, 656 AND 657, 1999 EDITION. VICINITY MAP �� TERRA GARRY MARSHALL PROPERTY ••• ASSOCIATES RENTON, WASHINGTON Geotechnicai Consultants Proj.No. 3472-6 Date FEB. 1999 Figure 1 N E 4 T H S T R E E T I RETAIL ( I � I � I � TP'� � IP I �' icaTE A i �' I 1 1 � P 9 I � c /a , APPROXIMATE SC,ALE � � � /j j/ i 80 0 8G 160 � � -- �— / — -- __ � / �T �� E � i � ' TP-II _ ' , ��s� � wEr�.�� i LEGEND: I i �� i � � H h��,� `, I � APPROXIMATE TEST PIT LOCATION F �, t F e°� �� cn � \� I I l ( � � �__ w � --� I � � � �� ¢ i ' � L K ,� \ �`, � REFERENCE: . � EMERCENCY ��;�. ' — � �',� PRELIMINARY SITE PLAN PROVIDED BY � A`�ESS � `, TP-5 � I ROBERT S. DAVEY, JANUARY 1999. � 1 � I - - M�/ —I�— N/ P � TP-2 1� � � / � TP� '�, '; � � � � 1 '� ,� 1 TP-3 � I � , t TP-I �nE'�e.no � / ( � uEri�FiioN � 11 �/' / � '� � ' TP-4 ' Q � � i � / / STORM DETEN.'104 k 810FlLTRATION ( �� I 1 ( I�/ �� EXPLORATION LOCATION PLAN ��r��~�� TERRA GARRY MARSHALL PROPERTY ••• ASSOCIATES RENTON, WASHINGTON Geotechnicai Consultants Proj.No. 3472-6 Date FEB. 1999 Figure 2 BUILDING SLAB ; ��/��/\�/��i /. � /. � /. � /.� /. - . . ./ \ � . COM PACTED \� � . �..`ST�UC�URAL .,. ... �\ � : . .BA�K.FILL�,:. : � ��=/ � ' � . / � . . - � � . /�� o o .o° �� . . . . . . . . . . . . + ° ,i i � . � . � . � . � . � . � . � . � . � . � . � . o ��. % /� /� /� /� /� /� /� / �% 4" PERFORATED PIPE WASHED ROCK NOT TO SCALE � � � TERRA nPICAL FOOTING DRAIN DETAIL �:��r�� GARRY MARSHALL PROPERTY .•. ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj.No. 3472-6 Date FEB. 1999 Fgure 3 ( i APPENDIX A FIELD EXPLORATION AND LABORATORY TESTING Garry Marshall Property Renton,Washington We performed our field exploration at the site by excavating 12 backhoe test pits to depths ranging from 9.5 to 11.0 feet below existing surface grades. The test pit locations are shown on the Exploration Location Plan, Figure 2. The test pit locations were approximately determined by pacing and measuring with a hip chain relative to site boundaries, features, and adjacent test pits. Test pit elevations were interpreted from a topographic survey for the subject site,prepared by Triad Associates, Inc., dated December 1, 1998. The Test Pit Logs are presented on Figures A-2 through A-7. An engineer from our office maintained a log of each test pit as it was excavated, classified the soil conditions encountered, and obtained representative soil samples. All soil samples were visually classified in accordance �vith the Unified Soil Classification System shown on Figure A-1. Representative soil samples obtained from the test pits were placed in sealed plastic bags and taken to our laboratory for further examination and testing. The moisture content of each sample was measured and is reported on the Test Pit Logs. Grain size analyses were performed on four of the samples, the results of which are presented on Figures A-8 and A-9. Project No. T-3472-6 MAJOR DIVISIONS LETTER TYPICAL DESCRIPTION SYMBOL Clean GW Well-graded gravels, gravel-sand mixtures, little or no GRAVELS Gravels fines. J � (less than GP Poorly-graded gravels, gravel-sand mixtures, little or O � N More than 5% fines) no fines. � �'v� 50% of Coarse Silty gravels, gravel-sand-silt mixtures, non-plastic fraction is Gravels GM tines. � � � larger than No. �•— 4 sieve with fines Z � � GC Clayey gravels, gravel-sand-clay mixtures, plastic fines. 0 � �N Clean SW Well-graded sands, gravelly sands, little or no fines. o SAN DS Sands � �Z (less than Poorly-graded sands or gravelly sands, little or no � c More than 5/o fines) SP fines. � � � 50% of coarse � p o� fraction is ; SM Silty sands, sand-silt mixtures, non-plastic fines. U � smaller than Sands No. 4 sieve with fines � ; S(�, Clayey sands, sand-clay mixtures, plastic fines. Inorganic silts, rock flour, clayey silts with slight J •� o SILTS AND CLAYS M� plasticity. � o ,� � � N CL Inorganic clays of low to medium plasticity, (lean clay). � E o � Liquid limit is less than 50% � o Z•� i �L Organic silts and organic clays of low plasticity. Z `n� > I Q c �- � MF-{ Inorganic silts, elastic. � � a��' SILTS AND CLAYS C� »�-— W � � I C�"i Inorganic clays of high plasticiry, fat clays. z � v� Liquid limit is greater than 50% , u.- �H Organic clays of high plasticity. HIGHLY ORGANIC SOILS I PT Peat. DEFINITION OF TERMS AND SYMBOLS w Standard Penetration 2• pUTSIDE DIAMETER SPLIT Q I Density Resistance in Blows/Foot I SPOON SAMPLER � � Very loose 0-4 � 2.4" INSIDE DIAMETER RING SAMPLER o Loose 4-10 OR SHELBY TUBE SAMPLER Medium dense 10-30 z Dense 30-50 1 WATER LEVEL (DATE) � Very dense >50 , Tr TORVANE READINGS, tsf , Standard Penetration Pp PENETROMETER READING, tsf �� } Consistency Resistance in Blows/Foot I�, � DD DRY DENSITY, pounds per cubic foot U Very soft 0-2 LL LIQUID LIMIT, percent o Soft 2-4 � Medium stiff 4-8 PI PLASTIC INDEX I J � Velry stiff 6132 N STANDARD PENETRATION, blows per foot Hard >32 TERRA UN'�GARRY�I MA SHALLCPRO ERTY TEM • ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj. No. T-3472-6 Date FEB 1999 Figure A-1 Test Pit No. TP-1 ' Logged by: KPR Approximate Elev. 396 ft. Date: 2/12/98 Depth Moisture �ft•) Soil Description C��o�nt � (10 inches TOPSOIUDUFF) Brown silty very fine SAND with gravel, loose to medium dense,wet 33.9 becomin saturated.Weathered till. SM 1 ' Yellow-tan,mottled silty fine to medium SAND with gravel and 11.9 I 5 occasional cobbles,very dense, moist with saturated sandy lenses. , Glacial till.(SM) Becomes gray and with no mottles at 4 feet. 14 2 I 1� Test pit terminated at 10 feet. �� Moderate seepage perched and from sandy lenses at and below 2.5 feet. '� No caving. ' 15 �, Test Pit No. TP-2 Logged by: KPR Approximate Elev. 397 ft. Date: 2/12/98 , Depth Moisture (ft•) Soil Description Cootent � (/o) (10 inches TOPSOIL) � Brown silty very fine SAND with gravel and abundant roots,medium 32.5 dense, moist to wet. Weathered till.(SM) _ Yellow-tan, mottled silty fine to medium SAND with gravel and ' 5 occasional cobbles,very dense, moist with saturated sandy lenses. 13.2 Glacial till. (SM) Becomes gray and with no mottles at 4.5 feet. 16.5 10 Test pit terminated at 10 feet. Moderate seepage perched and from sandy lenses at and below 3 feet. No caving. ' 15 TEST PIT LOGS TERRA GARRY MARSHALL PROPERTY ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj. No. T-3472-6 Date FEB 1999 Figure A-2 Test Pit No. TP-3 Logged by: KPR Approximate Elev. 399 ft. Date: 2/12/98 Depth Moisture Content �ft•) Soil Description o�o� Q (5 inches DUFF) Brown to tan silty medium to coarse SAN D with some gravel and occasional 1�4 cobbles, medium dense, moist becoming saturated.Weathered till. (SM) _ Gray silty fine to medium SAND with some gravel,occasional cobbles, 5 very dense,moist with saturated zones. Glacial till. (SM) ��2 Becomes finer grained. 13.8 1� Test pit terminated at 10 feet. Moderate perched seepage at 3 feet. Light seepage from sandy lenses below 3 feet. No caving. 15 Test Pit No. TP-4 Logged by: KPR Approximate Elev. 402 ft. Date: 2/12/98 Depth Moisture (ft•) Soil Description C��oj nt � TOPSOIL Brown silry very fine to fine SAND with few gravel inclusions, medium �9.3 n m i t W th r till = Yellow-tan becoming gray,mottled(to 4 feet)silry fine to medium 5 SAND with some gravel and occasional cobbles,very dense, moist g.g with saturated zones. Glacial till. (SM) 13.2 1� Test pit terminated at 1�feet. Perched light seepage at 3 feet and from sandy lenses below 6 feet. No caving. 15 TEST PIT LOGS TERRA GARRY MARSHALL PROPERTY ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj. No. T-3472-6 Date FEB 1999 Figure A-3 Test Pit No. TP-5 Logged by: KPR Approximate Elev. 401 ft. Date: 2/12/98 Depth Moisture {ft.) Soii Description Co�oj nt � (10 inches TOPSOIL) Brown silty fine to medium SAND with few gravel inclusions, medium 25.5 dense,moist.Weathered till.(SM) � Yellow-tan,mottled(to 5 feet)becoming gray,silty fine to medium 12 8 5 SAND with some gravel and occasional cobbles,very dense,moist with occasional saturated zones. Glaciat till. (SM) 11.6 1� Test pit terminated at 10 feet. Perched very light seepage at 3 feet and from sandy lenses below 3 feet. No caving. 15 Test Pit No. TP-6 ' Logged by: KPR Approximate Elev. 397 ft. , Date: 2/12/98 Depth Moisture (ft•) Soil Description C��o)nt � (8 inches TOPSOIL) Brown silty medium SAND, loose, moist. Recessional outwash. (SM) 30.0 I 1 Yellow-tan and mottled to 4 feet becoming gray,silty fine to medium �, 5 SAND with gravel,dense,saturated at 2.5 feet becoming moist with 12.4 I , saturated zones. Glacial tilL (SM) � 10.7 I 10 � Test pit terminated at 10 feet. Perched light seepage at 2.5 feet and from saturated sandy lenses below 2.5 feet. 15 TEST PIT LOGS TERRA GARRY MARSHALL PROPERTY ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj. No. T-3472-6 Date FEB 1999 Figure A-4 Test Pit No. TP-7 Logged by: KPR Approximate Elev. 394 ft. Date: 2/12/98 Depth Moisture Content - �ft•) Soil Description �o�o� Q (10 inches TOPSOIL) Brown silty medium SAND, loose, moist to wet. Recessional outwash. 31.4 (SM) _ Yellow-tan, motted,silty GRAVEL with fine to medium sand, 5 very dense, moist,with saturated sandy zones. Till-like. (GM) Becomes gray and with no mottles at 5 feet. 1 o 2 14.7 1� Test pit terminated at 10 feet. Perched moderate seepage at 3 feet and light seepage in sandy zone below 3 feet. No caving. 15 Test Pit No. TP-8 Logged by: KPR Approximate Elev. 396 ft. Date: 2/12/98 Depth Moisture (ft•) Soil Description C��oj nt � (10 inches TOPSOIL) Brown becoming tan,faintly mottled silty medium SAND, loose 16.5 to 2 feet becoming medium dense, moist. Recessional outwash. (SM) Becomes coarser-grained. 5 21.5 Gray silty medium to coarse SAND with some gravel,dense,wet 1 to saturated. Till-like. (SM) 12•9 1 O Test pit terminated at 10 feet. Moderate seepage at 7.5 feet. No caving. 15 TEST PIT LOGS TERRA GARRY MARSHALL PROPERTY ASSOCIATES RENTON, WASHINGTON Geotechnical Co�sultants Proj. No. T-3472-6 Date FEB 1999 Figure A-5 Test Pit No. TP-9 Logged by: KPR Approximate Elev. 398 ft. Date: 2/12/98 Depth Moisture Content �ft•) Soii Description �o�o� � (5 inches TOPSOIL) Brown silty fine to medium SAND with few ravel inclusions, loose to 13.� medium dense moist. Weathered till. SM Yellow-tan and mottled becoming gray(at 4 feet), silty fine to coarse SAND with gravel, cobbles, and occasional boulders,very dense, _ 5 moist to 6.5 feet becoming saturated in sandy zones. Glacial till. (SM) 9.4 1 13.0 10 Test pit terminated at 11 feet. Moderate seepage at 6.5 feet and below from sandy layers. No caving. 15 Test Pit No. TP-10 Logged by: KPR Approximate Elev. 400 ft. Date: 2/12/98 Depth Moisture (ft.) Soil Description ��o�nt � (8 inches TOPSOIL) Brown silty medium SAND, loose, moist. Fiecessional outwash. (SM) Yellow-tan,mottled sandy SILT,fractured,very stiff(Pp=1.75 tsf), 2g.4 moist non- lastic. ML 5 Gray silty fine to medium SAND with some gravel and cobbles,�ery = dense, moist with saturated lenses. Glacial till. (SM) 11.3 10.6 1� Test pit terminated at 9.5 feet. Seepage from sandy layers below 4.5 feet. ' No caving. 15 TEST PIT LOGS TERRA GARRY MARSHALL PROPERTY ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants proj. No. T-3472-6 Date FEB 1999 Figure A-6 Test Pit No. TP-11 Logged by: KPR Approximate Elev. 399 ft. Date: 2/12/98 Depth Moisture �ft•) Soil Description C��oj nt � (2 inches Red-brown silty fine SAND with few gravel inclusions, loose to medium 1 dense moist becomin saturated. Weathered till. SM 33.2 Light gray-brown, mottled silty fine to medium SAND with some gravel and occasional cobbles,very dense, moist. Glacial till. (SM) �2 2 5 Becomes gray at 4 feet. 12.0 �� Test pit terminated at 11 feet. Moderate seepage perched at 1.5 feet and from sandy zones below 1.5 feet. No caving. 15 Test Pit No. TP-12 Logged by: KPR Approximate Elev. 399 ft. Date: 2/12/98 Depth Moisture (ft•) Soil Description C��oj nt � (7 inches TOPSOIL) Brown silty fine to medium SAND with few gravel inclusions, loose, 1 wet to saturated. Weathered till. SM 31.5 Light brown-gray, mottled silty fine to medium SAND with some 5 gravel and occasional cobbles,very dense,saturated. 21.0 Glacial till. (SM) 16.9 1� Test pit terminated at 10 feet. Moderate perched seepage at 1 foot. Moderate seepage from sandy lenses in till below 3 feet. No caving. 15 TEST PIT LOGS TERRA GARRY MARSHALL PROPERTY . ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj. No. T-3472-6 Date FEB 1999 Figure A-7 � � � �� . � � �• � � �••� � . ,. .. - - - = = = - - - - - = = = = = = � �� ,��■■�� / ��i�►��■■■�� % ��■■■■�� ■��■�� •� ��t ��■■■�� , � ��►��■�■�� ■�■�� : ��i�■��■■■�� '��■■�� ► :� ��'a■��■�■�� ■■�� ' ��■�� ■�� ' ' ��a.��■■■�� - � ��■■■�� ' • � • � ��t`'a��■��■■■�� ■■��■� � . . ��:��■■�� :��-��■■�� ►��■■■�� ► .� ��■��■��■■��■� .� • ��■��■■�� ■�� • �� ■■�� . ��Z-��►��■■�� . � �� . ��■■�� ■�� ■��■�� .. ��■��►��■��■■�� ' ��■��■�■�� .� ��■■�� `'-��-��■��■■■■�� '� .. ��i►��■�� ■��■��■�� ' ��■��7�\��■��■■�� . 1 �� '��■■■■�� 1 ��■��■■�� ■��■■■�� • ��t=��■�� 7��■�■�� 1 �� ■■■�� • ��■■■�� •1 ��■��■■�■�� :�7��■■■■�� ■��■��■■�� 1 ��■��■■■�� •1 • ��■�� v��■�■■�� ■��■■�� 1 � �1��1 ��-��11��,��1�� 11 • • • • " � � .� • � � � :• � � ' � � � � � � � � � � .. � .. �'' �� : . �.. ��I:�:PL�� 9:L`l� • • . � �• �-. � �- . . • /• '• �� . .. • 1 1 . � • ' . 1 '� � � � . �� . � �• � �••� � . .. .. - - - = = = - - - - - = = = = = = �� •��■■�� ■��■■�� / ��a��■■■�� ►��`��■��■■�� • ��■��■■■�� . % ' ■�� ■■■■�� ■■�� • ��►��■■�� ■��'��■■�� ► •� ��a=��-�� ' �� ■■■■�� . ��_��■■�� • ��■��■■■�� ' ��■��:��■■�� ' • � . � ■��■��■��■�■�� ■■�� ► ��'�■��■■�.�� :��■■■�� ►��■■■�� ` .� ��■�■�� .� • ��■��\��■■�� !��■■■�� • ��'��■■�� ' ��r��\��■■■�� 1 ��■■■■�� 1 � ��■�� ■��\�\��■�� •� ��i��■��■■�■�� ►t.��■�■�� •1 ��■■�� _��■■�� •� •� ��■�■�� 5��!1��■�� ' ��■��`��■■�� • 1 ��_��■�� 1 ��■��_\�■��■�■�� '7��■�■�� • ��!��■■�� /��■■■�� 1 ��■�� ' ��■■■■�� .1 �� • ��■�� ■�� • � 1 ��■■■�� •1 ��■■■■�� ■\�� ` ��■�■■�� 5��■��■■�■�� • � ��■I��I�I�I��1��11■��1�1��11■��■11��■■�� 11 � � � � � � � • • � � � � • � � � � � � ' � � � � � � � •• . • ► �ii �� ►�:�� :�►�� • • � � � • �• �-• � �' • • • ,' • • �� ' i 1 � 1 • ' ' 1 � � -