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HomeMy WebLinkAboutCOM2005-00088 Soils and Slope Analysis Review - COM Engineering / Geo-Tech Reports - 8/1/2005 �oN STgTF°� MASON COUNTY MO s... o s = PUBLIC WORKS DIRECTOR/COUNTY ROAD ENGINEER Shelton,Washington 99594 Y y ,864 a DATE: Aug. ls`, 2005 INTER-DEPARTMENTAL COMMUNICATIONS TO: Kell McAboy, DCD - Planner FROM: Alan A. Tahja, P/W - Co. Hydr. Engr. WO# PLG-05 SUBJ: Soils & Slope Analysis Review NAME: Harmony Hill (CIS, 7362 E SR 106 COM2005-00088 Kell, The"Soils and Slope Analysis"prepared for the proposed Harmony Hill building addition to be constructed at 7362 East State Route 106,has been received and reviewed by Public Works. The report was prepared to investigate an apparent instability of the native soils around the construction area,though the ground slope at the project location may be less than would trigger a geotechnical assessment level site investigation. The report does indicate that the site contains soils with a high erosion potential if not properly controlled. Accompanying the report is a site plan which includes Erosion and Sediment(E&S)Control features which should be implemented to the extent necessary to ensure no silt or mud leaves the construction area. Since the proposed new structure will be situated in place of an existing tennis court,the completed project is not expected to generate any substantial changes to stormwater runoff from the site. In summary,the geotechnical "Soils and Slope Analysis"/assessment prepared for the proposed multi-purpose building appears acceptable,and stability issues may be considered to have been adequately investigated and addressed. Please feel free to contact me at County extension 461 if you have any questions regarding these comments, or if you feel any features need further discussion or attention. Sincerely, L Al n A. Tahja File: H: \WP\GEO\Assessments\Harmony Hill Multi-Bldg.doc WORK ORDER -PUBLIC WORKS DEPT, 04, Date: -7/•2-`7 /o s -����II�r� IIIr PERMIT OF: Numban: t -b Authorized -- . by: P 1a.,��n.;w� Date' ��„� Type of Work, r,�. r.rr-�r�.r r>n►1 nni i�r V DI IRI I!^��� 't4.'�:' CHARGE TO: NAME AGENCY/COMPANY v BIWNG ADDRESS PHONE c Q mi Pub.Works in Cha e: !c1 Pro Time ne: (from-to dpt / e TO ProJod �� ESQ t*h Dftr,. ESTIMATED TOTAL$V: • • C08?'#$TlMATE ' IW ads 11OU I' FdM!K TOTAL i TWAL n EOMWMENr USED: MATENAL USED: / (19 Acftd cost ; pftO4m DATE Employes "�"—' Nam tB ll , Hours SUN Ed�4.li TOTAL$ EQUIPMENT USED: g JQTAL 111 MATERIAL.USED: TOTAL ALL3) BILLED DATE_�_I►ry��� PAID DATE RE0.0 00 GEOTECHNICAL TESTING LABORATORY HARMONY HILL RECEIVED 7362 EAST STATE ROUTE 106 'JUL 21 2v05 UNION, WA 98:592 426 W CLUAK Attn: David Short ��T PL�`i�,rl rTM�ll`tG. Re: Soils and Slope analysis Project: proposed building at tennis court, Harmony tfi11 Report Date: 6I1/2005 Gentlemen: As per your request, we have conducted a soils exploration and foundation evaluation for the above mentioned project. The results of this investigation, together with our recommendations, are to be found in the following report. We have provided three copies for your review and distribution. During our exploration, three test borings were advanced and soil samples submitted for laboratory testing from the project site. The data has been carefully analyzed to determine soils bearing capacities and footing embedment depths. The results of the exploration and analysis indicate that conventional spread and continuous wall footings appear to be the most suitable type of foundation for the support of the proposed structures. Some variability was encountered in comparing the soil profiles of the site. Net allowable soil pressures, embedment depth, and total expected settlements have been presented for the site later in the report. Often, because of design and construction details that occur on a project, questions arise concerning soil conditions. We would be pleased to continue our role as geotechnical consultants during the project implementation. We appreciate this opportunity to be of service to you and we look forward to working with you in the future. If you have any questions concerning the above items, the procedures used, or if we can be of any further assistance please call us at the phone number listed below. o4 Wash,. Respectfully Submitted, GE,OTECHNICAL TESTING LABORATORY 1 Harold Parks, L.G., L.E.G. t+ Senior Engineering Geologist MAROLD PARKS 10011 Blomberg SirW SW,01pnpia,WA 98512 1 Phone#(360)7544612 Fax#(360)7544U8 G EOTECHNICAL TESTING LABORATORY Table Of Contents Table Of Contents ! Subsurface Investigation s Introduction: 3 Authorization: 3 Purpose: 3 Scope: 3 General: 3 Geology Of Area: 4 Climate Of Area: 4 Field Exploration 4 General Notes: 4 Drilling&Sampling Procedures: 4 Laboratory Testing Program: 5 Project Description s Subsurface Conditions 6 General Notes: 6 Description Of Foundation Materials: 6 Foundation Discussion And Recommendations 6 General Notes: 6 Foundation Design Recommendations: 6 Construction Considerations 7 Earthwork: 7 Structural Fill: 7 Excavations: 7 Lateral Earth Pressures: 8 Floor Slab-On-Grade: 8 Groundwater Control: 8 Geoseismic Setting: 9 Liquefaction Potential: 9 Slope Stability: 9 Building Setback: 10 Summary 10 Geotechnical General Notes I I Soil Property Symbols 11 Drilling And Sampling Symbols 11 Relative Density And Consistency Classification 11 Particle Size I I Vicinity Map 12 Boring Log#1 Is Boring Log#2 14 Boring Log#3 Is 10011 Blomberg Street SW,Olympia, WA 98512 2 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY Subsurface Investigation INTRODUCTION: This report presents the results of a soils exploration and foundation analysis for the proposed building. This investigation was conducted for Harmony Hill. AUTHORIZATION: Authorization to perform this exploration and analysis was in the form of a written authorization to proceed from David Short. PURPOSE: The purpose of this foundation exploration and analysis was to determine the various soil profile components, the engineering characteristics of the foundation materials and to provide criteria for use by the design engineers and architects in preparing or verifying the suitability of the foundation design. SCOPE: The scope of the exploration and analysis included a review of geological maps of the area and a review of geologic and related literature, a reconnaissance of the immediate site, the subsurface exploration, field and laboratory testing, and an engineering analysis and evaluation of the foundation materials. We were not requested to provide an Environmental Site Assessment for this property. Any comments concerning onsite conditions and/or observations, including soil appearances and odors,are provided as general information. Information in this report is not intended to describe,quantify or evaluate any environmental concern or situation. GENERAL: The exploration and analysis of the foundation conditions reported herein are considered sufficient in detail and scope to form a reasonable basis for the foundation design. Any revision in the plans for the proposed structure from those enumerated in this report should be brought to the attention of the soils consultant so that he may determine if changes in the foundation recommendations are required. If deviations from the noted subsurface conditions are encountered during construction,they should also be brought to the attention of the soils consultant. 10011 Blomberg Street SW,Olympia,WA 98512 3 Phone#(360)7544612 Fax#(360)7544848 GEOTECHNICAL TESTING LABORATORY The soils consultant warrants that the findings, recommendations, specifications, or professional advice contained herein, have been promulgated after being prepared according to generally accepted professional engineering practice in the fields of foundation engineering, soil mechanics and engineering geology. No other warranties are implied or expressed. This report has been prepared for the exclusive use of Harmony Hill and its retained design consultants. Findings and recommendations within this report are for specific application to the proposed project. All recommendations are according to generally accepted soils and foundation engineering practices. GEOLOGY OF AREA: The Soil Survey of Mason County, USDA Soil Conservation Service (1960)has mapped the site soils as an Alderwood gravelly sandy loam, 15-30 percent slopes (AJ and Alderwood gravelly sandy loam, 5-15 percent slopes (Ab). The Alderwood soils typically formed from glacial advance outwash. They are described as having good natural drainage. Typically, there is no occurrence of a high water table. Internal drainage is described as medium. An erosion hazard may exist if the vegetation is removed; otherwise the soil has a low erosion hazard in its present condition. Cementation is usually present. CLIMATE OF AREA: The climate of the site area is temperate and marine. The influence of the Puget Sound and the Pacific Ocean modifies summer and winter temperatures and eliminates periods of extreme heat and cold. Field Exploration GENERAL NOTES: The field exploration to determine the engineering characteristics of the foundation materials included a reconnaissance of the project site, excavating the test borings, performing field penetrometer and vane shear tests and recovering disturbed grab samples. A total of three test borings were placed on the site. Test borings were advanced to twelve feet below the existing ground surface. Test borings were located by the field crew as near as possible to the corners and foundation of the proposed building. The tennis court area was used to locate and position the excavations. The test borings were located by the field technician by means of normal taping and pacing procedures and are presumed to be accurate to within a few feet. After completion,the test borings were backfilled with excavated soils and the site cleaned and leveled. DRILLING&SAMPLING PROCEDURES: The soil borings were performed with a limited access hollow stem auger drill rig. Representative samples were obtained from the borings at 5 ft. soil intervals. The samples obtained by this procedure were classified in the field by a soils technician, identified according to test boring number and depth, placed in plastic bags to protect against moisture loss and transported to the laboratory for additional testing. Standard penetration was measured using a two-inch outside diameter, split-spoon sampler driven by a pin-guided, 140- pound weight, free falling 30 inches. The blows per six-inch interval were recorded. The first six-inch drive interval is allowed for seating the sampler. The blow counts for two six-inch intervals, when combined, yield the Standard Penetration Resistance (N-Value) of the soils encountered in the sample interval. The number of blows required to drive the sampler the last 12 inches provides a measure of the relative density of granular soils or the consistency of cohesive soils. When the number of blows exceeds 50 for a six-inch or less advancement of the sampler,refusal is inferred. 10011 Blomberg Street SW,Olympia,WA 98512 4 Phone#(360)7544612 Fax#(360)7544848 GEOTECHNICAL TESTING LABORATORY The results obtained from the Standard Penetration Test, along with other tests and geotechnical judgments, were used to develop the recommendations of this report. In addition to the N-value,we tested the soils in the sampler tip using a pocket penetrometer. The data developed by this test presents an estimate of the bearing capacity of the soils by measuring the resistance to penetration. This information is presented with the boring log. LABORATORY TESTING PROGRAM: Along with the field investigation, a supplemental laboratory testing program was conducted to determine additional pertinent engineering characteristics of the foundation materials necessary in analyzing the behavior of the proposed building structure. The laboratory testing program included supplementary visual classification and water content determinations on all samples. In addition, selected samples were subjected to Grain Size Analysis -ASTM designation C-117,C-136. All phases of the laboratory testing program were conducted according to applicable AST'M Specifications and the results of these tests are to be found on the accompanying logs located in the Appendix. Project Description The site of the proposed building upon which this soils exploration has been made is located at 7362 East State Route 106 in Mason County near Union, Washington. The site topography for the building consists of a cut and fill area made level for the existing _ tennis court. The site drainage consists of surface and groundwater being , controlled by ditch and >. r discharged to a previously '. designed and _ operating drainage " system. The _ site vegetation is very sparse, consisting of grass and evergreens on the southern side of the proposed building area. The purpose of this section is to enumerate details of the proposed structure. The following information was provided by the project supervisor. The tennis court will be replaced with a two story wood frame structure. No basements are planned. Conventional spread footings and slab-on-grade floors are contemplated. Differential settlements are limited to 3/4 inch. Loads of 2,000 pounds per lineal foot for wall footings and 80,000 pounds for columns were assumed for settlement calculations. 10011 Blomberg Street SW,Olympia,WA 98512 5 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY Subsurface Conditions GENERAL NOTES: The types of foundation materials encountered have been visually classified and are described in detail on the test boring logs provided in the Appendix. The results of the field penetrometer and vane shear tests, moisture contents and other laboratory tests are presented on the logs. It is recommended that the logs not be used for estimating quantities due to highly interpretive results. DESCRIPTION OF FOUNDATION MATERIALS: The surface of the proposed construction site is covered with concrete and 6 to 12 inches of topsoil that should be removed prior to the start of any construction due to the high compressibility of these soils. The soil profiles encountered were relatively consistent among the three borings. Silty sandy loam layers were encountered beneath the surface and extended to depths beyond the scope of this investigation. Lines of demarcation represent the approximate boundaries between the soil types, but the transitions may be gradual. It is to be noted that, whereas the test borings were placed and sampled by an experienced technician, it is sometimes difficult to record changes in stratification within narrow limits. In the absence of foreign substances, it is also difficult to distinguish between discolored soils and clean soil fills. It is recommended that the logs not be used for estimating quantities due to highly interpretive results. Foundation Discussion And Recommendations GENERAL NOTES: Various foundation types have been considered for the support of the proposed building structure. Two requirements must be satisfied in the design of foundations. First, the load must be less than the ultimate bearing capacity of the foundation soils to maintain stability, and secondly, the differential settlement must not exceed an amount that will produce adverse behavior to the superstructure. The allowable settlement is usually exceeded before bearing capacity considerations become important; thus, the allowable bearing pressure is normally controlled by settlement considerations. Considering the subsurface conditions and the proposed construction, it is recommended that the structure be founded upon conventional spread and continuous wall footing foundations. Settlements should not exceed tolerable limits if the following design and construction recommendations are observed. FOUNDATION DESIGN RECOMMENDATIONS: On the basis of the data obtained from the site and the test results from the various laboratory tests performed, we recommend that the following guidelines be used for the net allowable soils bearing capacity. Net Allowable Footing ASTM D 1557 Soils Bearing Depth Subgrade Compaction Capacity 18 inches 95% 2,000 lbs1f 10011 Blomberg Street SW,Olympia,WA 98512 6 Phone#(360)7544612 Fax#(360)7544848 GEOTECHNICAL TESTING LABORATORY The footings should be proportioned to meet the stated bearing capacity and/or the International Building Code's 2003 minimum requirements. Total settlement should be limited to 1 inch total with differential settlement of% inch. Any excessively loose or soft spots or areas that do not meet the compaction requirements that are encountered in the footing subgrade will require over-excavation and backfilling with at least 2 feet of structural fill. In order to minimize the effects of any slight differential movement that may occur due to variations in the characters of the supporting soils and any variations in seasonal moisture contents, it is recommended that all continuous footings be suitably reinforced to make them as rigid as possible. Construction Considerations EARTHWORK: It is recommended that the final exposed subgrade be inspected by a representative of the soils consultant. This inspection should verify that all organic material has been removed. Any soft spots or deflecting areas should be removed to sound bearing and replaced with structural fill. Once the existing soils are excavated to the design grade,proper control of the subgrade conditions(i.e.,moisture content) and the placement&compaction of new fill(if required)should be maintained by a representative of the soils consultant. The recommendations for structural fill presented within this report can be utilized to minimize the volume changes and differential settlements that are detrimental to the behavior of footings and floor slabs. Enough density tests should be taken to monitor proper compaction. For structural fill beneath building structures, one in-place density test per lift for every 1,000 ft2 is recommended. In parking and driveway areas this can be increased to two tests per lift for every 1,000 ft2. Excavation equipment may disturb the bearing soils and loose pockets can occur at the bearing level that were not disclosed by the soils borings. For this reason, it is recommended that the bottoms of the excavations be compacted in- place by vibratory compactors. The upper 12 inches should be recompacted to achieve an in-place density of not less than 95%of the maximum dry density as determined by ASTM D-1557. STRUCTURAL FILL: Structural fill should consist of a 3 inch minus select, clean, granular soil with no more than 7% fins (4200). The fill should be placed in lifts not to exceed 12 inches in thickness. Each layer of structural fill should be compacted to a minimum density of 95% of the maximum dry density as determined by ASTM designation D-1557. For structural fill below footings, the area of the compacted backfill must extend outside the perimeter of the foundation for a distance at least equal to the thickness of the fill between the bottom of the foundation and the underlying soils. If it is elected to utilize a compacted backfill for the support of foundations,the subgrade preparation and the placing of the backfill should be monitored continuously by a qualified soils consultant or his representative so that the work is performed according to these recommendations. The use of on-site soils as structural fill is acceptable provided that not more than 7%fines pass the#200 sieve. It should be remembered that these materials require very high moisture contents for compaction and require a long time to dry out if natural moisture contents are too high. This makes moisture content, lift thickness, and compactive effort difficult to control. EXCAVATIONS: Shallow excavations required for construction of foundations that do not exceed four feet in depth may be constructed with side slopes approaching vertical. Below this depth it is recommended that slopes not exceed one vertical to one 10011 Blomberg Street SW,Olympia,WA 98512 7 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY horizontal. For deep excavations, the soils present cannot be expected to remain in position. These materials can be expected to fail and collapse into any excavation, thereby undermining the upper sandy materials. This is especially true when working at depths near a water table. Proper care must be taken to protect personnel and equipment. Care must be taken so that all excavations made for the foundations are properly backfilled with suitable material compacted according to the procedures outlined in this report. Before the backfill is placed, all water and loose debris should be removed from these excavations. This information is provided for planning purposes. It is our opinion that maintaining safe working conditions is the responsibility of the contractor. Jobsite conditions such as soil moisture content,weather condition,earth movements and equipment type and operation can all affect slope stability. All excavations should be sloped or braced as required by applicable local,state and federal requirements. LATERAL EARTH PRESSURES: Lateral earth pressures are dependent upon the backfill materials and their configuration and moisture content. Three inch minus sand and gravel mixtures that are free draining are recommended for backfilling walls greater than four feet tall. There are below grade retaining walls or walls designed for retaining earthen fills on this project. The following values may be used for this site for the sandy soils located above the till layer. Active Earth Pressure: 0.30 Coefficient Passive Earth Pressure: 200 lbs./ft/ft depth Friction: 0.45 Coefficient FLOOR SLAB-ON-GRADE: Before the placing of any concrete floors or pavements on the site, or before any floor supporting fill is placed, the subgrade should be proof rolled to confirm that the subgrade contains no soft or deflecting areas. Areas of excessive yielding should be excavated and backfilled with structural fill. Any additional fill used to increase the elevation of the floor slab should meet the requirement for structural fill. Structural fill should be placed in layers of not more than 12 inches in thickness, at moisture contents at or above optimum, and compacted to a minimum density of 95%of the maximum dry density as determined by ASTM designation D-1557. A granular mat should be provided below the floor slabs. This should be a minimum of four inches in thickness and properly compacted. The mat should consist of sand or a sand and gravel mixture with non-plastic fines. The material should all pass a 3/4 inch sieve and should contain less than 5% passing the #200 sieve. Because groundwater can be expected to be at shallower depths during the winter months a moisture barrier should be placed beneath all floor slabs. GROUNDWATER CONTROL: Groundwater was encountered at the time the field exploration was conducted. Groundwater is not expected to cause any difficulties during construction of this project provided the drainage swale on the south side of the proposed building is kept open and controlled. It is recommended that this runoff caused by wet weather and ground water be directed away from all open excavations. The onsite silty soils can be expected to become soft and pump if subjected to excessive traffic after becoming wet during periods of bad weather. This can be avoided by constructing temporary or permanent driveway sections should wet weather be forecast. 10011 Blomberg Street SW,Olympia,WA 98512 8 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY GEOSEISMIC SETTING: According to the Seismic Zone Map of the United States contained in the 2003 International Building Code (IBC), the project site is located where the maximum spectral response acceleration is 45 percent of gravity(g). Based on the subsurface conditions observed at the site, we interpret the site conditions to correspond to a seismic Soil Profile Type D, for Slightly Compact Soil, as defined by Table 1615.1.1 (IBC). This is based on the range of SPT (Standard Penetration Test)blow counts and/or probing with a'h-inch diameter steel probe rod. LIQUEFACTION POTENTIAL: Based on our review of the subsurface conditions, we conclude that the site soils are only mildly susceptible to liquefaction. The near-surface soils are generally in a slightly compact condition and the static water table is located near the surface. However, shaking of the soil is not apt to produce a denser configuration and subsequently excess pore water pressures are not likely to be produced. The Liquefaction Susceptibility Map of Mason County, Washington by Palmer, Magsino, Poelstra, Bilderback, Folger, and Niggemann(September 2004)maps the site area as having a very low liquefaction potential. SLOPE STABILITY: The Site Class Map of Mason County, Washington by Palmer, Magsino, Bilderback, Poelstra, Folger, and Niggemann (September 2004)maps the site area as site class C. Site class C is a very stiff soil or soft rock. Based on our field observations,explorations and our experience with the soil types encountered on the site,we conclude that although portions of the slopes on the lot exceed 100 percent, they are generally stable relative to deep-seated failure in their present configuration. The following figure represents a shear angle for the glacial till. Shear angle and cohesion are variables used to model the site. Peak Shear Stress vs.Normal Stress 2500 _ __._ .. _-7--7 2000 37' w fA a m 1500 d U) N 1000 POO< N Y a� t�V4n 500 f— n — 000-� 0 0 500 1000 1500 2000 2500 Normal Stress (psf) 10011 Blomberg Street SW,Olympia,WA 98512 9 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY These processes can be managed and the risk reduced through proper construction of the residence. Erosion control recommendations in the slope and buffer areas are provided in the `Building Setback" and "Erosion Control" sections of this report. BUILDING SETBACK: Slope stability was modeled using the GEO-SLOPE/W program(version 5.13)in both static and dynamic conditions(ca= 0.3). Factors of safety were determined using Bishop's,Janbu,and the Morgenstern-Price methods. The site geology was modeled using a monolithic layer of glacial till. The glacial till was determined to have a unit weight of 125 pcf,cohesion of 200 psf, and a shear angle (0) of 37°. Under static conditions, the slopes remained stable to deep-seated and shallow failure. Under dynamic loading, the 2704 computations demonstrated that the slope might be susceptible to surficial raveling; large deep-seated failure was not demonstrated by our model. The following figure illustrates a moment F.S. for the cross-section. This solution is the lowest factor of safety generated by the model. A building setback from landslide hazard areas is required unless evaluated and reduced by an engineering geologist or a licensed professional engineer. Based on our geotechnical evaluation of the site and our experience in the area, a building setback will be needed for this lot. No setback is needed for the immediate crest and toe of the minor slopes near the building. As previously discussed, weathering, erosion and the resultant surficial sloughing and shallow landsliding are natural processes that affect slope areas. Significant surficial raveling and/or sloughing was observed in the sloping portions of the site. To manage and reduce the potential for these natural processes,we recommend the following: 1) No drainage of concentrated surface water or significant sheet flow onto the sloped areas. 2) No filling unless retained by retaining walls or constructed as an engineered fill. 3) Water from the roof drains should be collected and disposed of as per the engineers' disposal plan. Summary When the plans and specifications are complete, or if significant changes are made in the character or location of the proposed structures, a consultation should be arranged to review them regarding the prevailing soil conditions. Then, it may be necessary to submit supplementary recommendations. It is recommended that the services of a qualified soils testing firm be engaged to test and evaluate the soils in the footing excavations before placing concrete to determine that the soils meet the compaction requirements. Monitoring and testing should also be performed to verify that suitable materials are used for structural fills and that they are properly placed and compacted. 10011 Blomberg Street SW,Olympia,WA 98512 10 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY Geotechnical General Notes SOIL PROPERTY SYMBOLS N: Standard"N'penetration: Blows per foot of a 140 pound hammer falling 30 inches on a 2 inch O.D.split-spoon. Q.: Unconfined compressive strength,tons/ft2 Qp: Penetrometer value,unconfined compressive strength,lbs/ftz V: Vane value,ultimate shearing strength,lbs/ft2 M: Water content,% LL: Liquid limit,% PI: Plasticity index,% D: Natural dry density,lbs/ft3 WT: Apparent groundwater level at time noted after completion. DRILLING AND SAMPLING SYMBOLS SS: Split-Spoon- 1 3/8"I.D., 2"O.D.,except where noted. ST: Shelby Tube-3"O.D.,except where noted. AU: Auger Sample. GB: Grab Sample. DB: Diamond Bit. CB: Carbide Bit. WS: Washed Sample. RELATIVE DENSITY AND CONSISTENCY CLASSIFICATION Terms(Non-Cohesive Soils) Standard Penetration Resistance Very Loose 0-2 Loose 2-4 Slightly Compact 4-8 Medium Dense 8- 16 Dense 16-26 Very Dense Over 26 Terms(Cohesive Soils) Q.-(tons/ft2) Very Soft 0-0.25 Soft 0.25-0.50 Firm(Medium) 0.50- 1.00 Stiff 1.00-2.00 Very Stiff 2.00-4.00 Hard 4.00+ PARTICLE SIZE Boulders 8 in.+ Coarse Sand 5 mm-0.6 mm Silts 0.074 mm-0.005 mm Cobbles 8 in.-3 in. Medium Sand 0.6 mm-0.2 mm Clays 0.005 mm&Smaller Gravel 3 in.-5 mm Fine Sand 0.2 mm-0.074 mm 10011 Blomberg Street SW,Olympia, WA 98512 11 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY Vicinity Map 'yliHcfol, t L3^3? 108 ` EDsbyRd o 0 w m 1000 ft O 2005 Yahoo'Inc ©2005 NAUTEQ 10011 Blomberg Street SW,Olympia,WA 98512 12 Phone#(360)7544612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY Boring Log #1 Date: File#: Boring Log#: 1 Client: Harmony Hills Boring Type: Hollow Stem Auger Depth Drilled: 15 feet Depth Field Change (Ft) Description in Soils %M N %3/4" %-#4 %-#200 Comments 1.0 silty sand(fill) FILL,medium brown,fine silty 2.0 12.0% 8 96% 74% 16% sand,dry,loose 3.0 native sandy loam with rock medium dense 4.0 5.0 wet 21.0% 18 dense gray silty sand with gravel 6.0 7.0 8.0 9.0 10.0 semi-cemented till 9.6% 50+ very dense gray silty sand with 11.0 gravel 12.0 13.0 14.0 15.0 end boring 50+ 16.0 17.0 18.0 19.0 Total depth=15 feet 20.0 21.0 22.0 23.0 24.0 25.0 26.0 27.0 28.0 29.0 30.0 31.0 10011 Blomberg Street SW,Olympia,WA 98512 13 Phone#(360)754-4612 Fax#(360)754-4848 GEOTECHNICAL TESTING LABORATORY Boring Log #2 Date: File#: Boring Log#: 2 Client: Harmony Hills Boring Type: Hollow Stem Auger Depth Drilled: 10 feet Depth Field Change (Ft) Description in Soils %M N % %-#4 %4200 Comments 1.0 native till dense[ill 2.0 silty sand with gavel 18 3.0 4.0 5.0 silty sand with gravel 32 very dense 6.0 7.0 8.0 9.0 10.0 end boring 39 native silty sand with 11.0 Gravel 12.0 13.0 14.0 15.0 16.0 17.0 18.0 19.0 20.0 21.0 22.0 23.0 24.0 25.0 26.0 27.0 28.0 29.0 30.0 31.0 10011 Blomberg Street SW,Olympia,WA 98512 14 Phone#(360)754-4612 Fax#(360)7544848 GEOTECHNICAL TESTING LABORATORY Boring Log #3 Date: File#: Boring Log#: 3 Client: Harmony Hills Boring Type: Hollow Stem Auger Depth Drilled: 10 feet Depth Field Change (Ft) Description in Soils %M N %3/4" %44 %4200 Comments 1.0 fill sand with gravel dense native till 2.0 native silty sand with gravel 19 3.0 wet 4.0 5.0 silty clayey sand with gravel 28 96% 87% 29% very dense 6.0 7.0 8.0 9.0 10.0 end boring 47 very dense 11.0 12.0 13.0 14.0 15.0 16.0 17.0 18.0 19.0 20.0 21.0 22.0 23.0 24.0 25.0 26.0 27.0 28.0 29.0 30.0 31.0 10011 Blomberg Street SW,Olympia,WA 98512 15 Phone#(360)7544612 Fax#(360)7544848