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Geotechnical Engineering Report

Proposed Sumner Middle School Improvements 11508 Willow Street

Sumner, Washington 98390

March 31, 2017 Revised May 4, 2017

prepared for:

Sumner School District No. 320 Attention: Mark Baumgarten, Facilities Director

19701 104th St E Bonney Lake, Washington 98391

prepared by:

Migizi Group, Inc.

PO Box 44840 Tacoma, Washington 98448

(253) 537-9400

MGI Project P878-T17

i

TABLE OF CONTENTS

Page No.

1.0 SITE AND PROJECT DESCRIPTION .............................................................................................. 1 2.0 EXPLORATORY METHODS ............................................................................................................ 2

2.1 Test Pit Procedures ................................................................................................................ 3 3.0 SITE CONDITIONS ............................................................................................................................ 3

3.1 Surface Conditions ................................................................................................................. 3 3.2 Soil Conditions ....................................................................................................................... 3 3.3 Groundwater Conditions ...................................................................................................... 4 3.4 Seismic Conditions ................................................................................................................. 5 3.5 Liquefaction Potential ........................................................................................................... 5 3.6 Infiltration Conditions and Infiltration Rate ...................................................................... 5

4.0 CONCLUSIONS AND RECOMMENDATIONS............................................................................ 7 4.1 Site Preparation ...................................................................................................................... 9 4.2 Spread Footings .................................................................................................................... 11 4.3 Slab-On-Grade Floors .......................................................................................................... 12 4.4 Drainage Systems ................................................................................................................. 12 4.5 Asphalt Pavement ................................................................................................................ 13 4.6 Structural Fill ........................................................................................................................ 15

5.0 RECOMMENDED ADDITIONAL SERVICES ............................................................................. 16 6.0 CLOSURE ........................................................................................................................................... 16

List of Tables

Table 1. Approximate Locations and Depths of Explorations ............................................................................. 2 Table 2. Laboratory Test Results for Non-Organic Onsite Soils .......................................................................... 6 Table 3. Laboratory Test Results for Treatment Capacity of Onsite Soils .......................................................... 7

List of Figures

Figure 1. Topographic and Location Map Figure 2 and 3. Site and Exploration Plan

APPENDIX A

Soil Classification Chart and Key to Test Data .................................................................................................. A-1 Logs of Test Pits TP-1 through TP-8 .......................................................................................................... A-2…A-9

APPENDIX B

Laboratory Testing Results .......................................................................................................................... B-1…B-6

APPENDIX C

AgSource Laboratories Cation Exchange Capacity Results

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MIGIZI GROUP, INC.

PO Box 44840 PHONE (253) 537-9400 Tacoma, Washington 98448 FAX (253) 537-9401

March 31, 2017 Revised May 4, 2017 Sumner School District No. 320 19701 104th St E Bonney Lake, WA 98391 Attention: Mark Baumgarten, Facilities Director Subject: Geotechnical Engineering Report Proposed Sumner Middle School Improvements 11508 Willow Street Sumner, WA 98390

MGI Project P878-T17

Dear Mr. Baumgarten: Migizi Group, Inc. (MGI) is pleased to submit this report describing the results of our geotechnical engineering evaluation of the improvements proposed for Sumner Middle School, located at 11508 Willow St in Sumner, Washington. This report has been prepared for the exclusive use of Sumner School District No. 320, and their consultants, for specific application to this project, in accordance with generally accepted geotechnical engineering practice. 1.0 SITE AND PROJECT DESCRIPTION The project site consists of the existing Sumner Middle School complex, which spans an approximately 21-acre area between Willow St (to the north) and SR 410 (to the south), directly west of the Maple Lawn Elementary School, in a densely populated residential region of Sumner, Washington, as shown on the enclosed Topographic and Location Map (Figure 1). The northern half of the school campus is largely occupied by the main school building, parking/driving facilities, and portable buildings; located west of the primary school structure. The main school building was originally constructed in 1975, and renovated in 2006, whereas the portables were constructed in 1985. The southern half of the school campus is occupied by tennis courts, a track, two baseball diamonds, and corresponding athletic fields. Improvement plans involve construction of an early learning center within the northwest corner

Sumner School District No. 320 – Proposed Sumner Middle School Improvements Revised May 4, 2017 Geotechnical Engineering Report P878-T17

Migizi Group, Inc. Page 2 of 16

of the southern half of the school campus, in an area currently occupied by tennis courts and a baseball diamond. This new development will also involve the expansion of driving/parking facilities adjacent to the new structure, the introduction of several new infiltration facilities, and improvements to the athletic fields, as indicated on the attached Figure 2. 2.0 EXPLORATORY METHODS We explored surface and subsurface conditions at the project site on February 18, 2017. Our exploration and evaluation program comprised the following elements:

• Surface reconnaissance of the site;

• Eight test pits (designated TP-1 through TP-8), advanced on February 18, 2017 and March 24, 2017;

• Three grain-size analyses performed on soil samples collected from our test pit explorations;

• Three Cation Exchange Capacity (CEC) tests performed on samples of the proposed soil treatment layer; and

• A review of published geologic and seismologic maps and literature. Table 1 summarizes the approximate functional locations and termination depths of our subsurface explorations, and Figure 2 depicts their approximate relative locations. The following sections describe the procedures used for excavation of test pits.

TABLE 1 APPROXIMATE LOCATIONS AND DEPTHS OF EXPLORATIONS

Exploration Functional Location Termination

Depth (feet)

TP-1 TP-2 TP-3 TP-4 TP-5 TP-6 TP-7 TP-8

Just inside of track surface, towards its center West of the southern extent of the track surface Towards the center of the southern baseball diamond Towards the north end of the northern baseball diamond West of the northern baseball diamond South of roughly the center of the tennis courts North of the baseball diamonds and east of the tennis courts Northwest corner of the project area; north of adjacent drainage swale

7½ 9 10 10 9 9 9

10½

The specific number and locations of our explorations were selected in relation to the existing site features, under the constraints of surface access, underground utility conflicts, and budget considerations. It should be realized that the explorations performed and utilized for this evaluation reveal subsurface conditions only at discrete locations across the project site and that actual conditions in other areas could vary. Furthermore, the nature and extent of any such variations would not become evident until additional explorations are performed or until construction activities have



begun. If significant variations are observed at that time, we may need to modify our conclusions and recommendations contained in this report to reflect the actual site conditions. 2.1 Test Pit Procedures Our exploratory test pits (TP-1 through TP-7) were excavated with a rubber-tracked mini-excavator operated by an excavation contractor under subcontract to MGI. Test Pit TP-8 was excavated with a rubber tired backhoe operated by an excavation contractor under subcontract to the client. An engineering geologist from our firm observed the test pit excavations, collected soil samples, and logged the subsurface conditions. The enclosed test pit logs indicate the vertical sequence of soils and materials encountered in each test pit, based on our field classifications. Where a soil contact was observed to be gradational or undulating, our logs indicate the average contact depth. We estimated the relative density and consistency of the in-situ soils by means of the excavation characteristics and the stability of the test pit sidewalls. Our logs also indicate the approximate depths of any sidewall caving or groundwater seepage observed in the test pits. The soils were classified visually in general accordance with the system described in Figure A-1, which includes a key to the exploration logs. Summary logs of the explorations are included as Figures A-2 through A-9. 3.0 SITE CONDITIONS The following sections present our observations, measurements, findings, and interpretations regarding, surface, soil, groundwater, and infiltration conditions. 3.1 Surface Conditions As previously indicated, the project site consists of the existing Sumner Middle School complex, which spans an approximately 21-acre area between Willow St (to the north) and SR 410 (to the south), directly west of the Maple Lawn Elementary School, in a densely populated residential region of Sumner, Washington. Improvements to the middle school complex will be focused within the southern half of the school property, in a region occupied by tennis courts, a track, two baseball diamonds, and corresponding athletic fields. This portion of the project area is relatively level, with minimal grade change observed over its extent. At the time of our site reconnaissance, standing water was observed in the drainage swale immediately east of the track, nearly to the point of overflow. No other hydrologic features were observed on site, such as seeps, springs, ponds and streams. Vegetation onsite is comprised primarily of lawn grass and isolated landscaping regions which contain ornamental trees and shrubs. A scattered growth of coniferous trees is located immediately south of the track, along the southern margin of the project area. 3.2 Soil Conditions Our test pit explorations revealed relatively consistent subgrade conditions across the project area, generally consisting of a surface mantle of sod and topsoil, underlain by native alluvial deposits. In the vicinity of test pit exploration TP-1, which was advanced towards the east side



of the track, adjacent to the drainage swale, alluvial soils varied in composition between fine silty sand and silt, with silt being the primary soil group. Soils were poorly drained, with rapid seepage being observed at a depth of 5½ feet below existing grade. Additionally, at this location, buried timber and other organic matter was encountered at a depth of 6½ feet below existing grade. The remainder of our explorations displayed a general progression of silty sands at or near ground surface elevations, grading to fine sand with depth. The depth of this transition varied, but generally occurred between 4 to 6 feet of existing grade. Groundwater seepage was also encountered within test pit explorations TP-2 and TP-7 at a depth of 8 feet. Based on our knowledge of the geology/hydrogeology of the region, we anticipate that seasonally high groundwater will rise within 12 feet of existing grade within all regions of the proposed improvement area. Alluvial soils were generally encountered in a loose/soft in situ condition. In the Surficial Geology of the Sumner Quadrangle, Washington, as prepared by the United States Department of the Interior Geological Survey (USGS) (1961), the project site is mapped as containing Qa, or Quaternary alluvium. This soil group consists primarily of sand and pebble to cobble gravel beneath modern flood plains, though silty sands and silts are commonly encountered. The National Cooperative Soils Survey (NCSS) for Pierce County, classifies onsite soils as 31A – Puyallup fine sandy loam. This soil series reportedly formed along alluvial flood plains; generally consisting of loamy fine sand to fine sand. Our subsurface observations generally conform with the classifications performed by the NCSS and the USGS. The enclosed exploration logs (Appendix A) provide a detailed description of the soil strata encountered in our subsurface explorations. 3.3 Groundwater Conditions At the time of our reconnaissance and subsurface explorations (February 18, 2017), we encountered groundwater seepage in four of our eight test pit explorations (TP-1, TP-2, TP-7, and TP-8). We observed rapid seepage at a depth of 5½ feet in the vicinity of test pit exploration TP-1, and slow seepage at a depth of 8 feet in the vicinity of test pit explorations TP-2 and TP-7. Additionally, slow seepage was observed at a depth of 10 feet towards the northwest corner of the project area, adjacent to test pit exploration TP-8. Given the fact that our explorations were performed towards the middle of what is generally considered the rainy season (October 1st through April 30th), during a period of extensive precipitation, we do not anticipate that groundwater will rise higher than that which we observed. In regions where groundwater was not encountered, we anticipate that seasonally high groundwater will rise within 12 feet of existing grade. Groundwater levels will fluctuate with localized geology and precipitation.



3.4 Seismic Conditions Based on our analysis of subsurface exploration logs and our review of published geologic maps, we interpret the onsite soil conditions to generally correspond with site class D, as defined by Table 20.3-1 in ASCE 7, per the 2015 International Building Code (IBC). Using 2015 IBC information on the USGS Design Summary Report website, Risk Category I/II/III seismic parameters for the site are as follows:

Ss = 1.241 g SMS = 1.245 g SDS = 0.830 g

S1 = 0.474 g SM1 = 0.724 g SD1 = 0.483 g

Using the 2015 IBC information, MCER Response Spectrum Graph on the USGS Design Summary Report website, Risk Category I/II/III, Sa at a period of 0.2 seconds is 1.25g and Sa at a period of 1.0 seconds is 0.72g. The Design Response Spectrum Graph from the same website, using the same IBC information and Risk Category, Sa at a period of 0.2 seconds is 0.83g and Sa at a period of 1.0 seconds is 0.48g. 3.5 Liquefaction Potential Liquefaction is a sudden increase in pore water pressure and a sudden loss of soil shear strength caused by shear strains, as could result from an earthquake. Research has shown that saturated, loose, fine to medium sands with a fines (silt and clay) content less than about 20 percent are most susceptible to liquefaction. Subsurface explorations performed within the confines of the project area revealed that native soils are comprised of silt, silty sand, and fine sand, which is often saturated within a depth of 5½ to 12 feet of existing grade. Given the geologic/hydrogeolgic conditions of the project area, we interpret this site as having a moderate susceptibility to liquefaction. In Section 4.2 of this report, we provide recommendations for the preparation of the foundation subgrade which would help mitigate some of this risk, however, during a large-scale seismic event, some degree of liquefaction and related post-construction settlement should be anticipated. We recommend that the structure be designed to prevent catastrophic collapse during a seismic event. 3.6 Infiltration Conditions and Infiltration Rate Based on our field observations and grain size analyses (presented in Table 2, page 6), it is evident that native, alluvial soils consist of slowly permeable silty sand at or near surface elevations, grading, in most instances, to moderately permeable, fine sand with depth. The depth of this transition typically ranges between 4 to 6 feet of existing grade. The results of our soil grain size analyses are presented below, and the attached Soil Gradation Graphs (Appendix B) display the grain-size distribution of the samples tested.



TABLE 2 LABORATORY TEST RESULTS FOR NON-ORGANIC ONSITE SOILS

Soil Sample, Depth % Coarse Gravel

% Fine Gravel

% Coarse Sand

% Medium

Sand

% Fine Sand

% Fines D10

TP-2, S-2, 6 feet TP-3, S-1, 6 feet TP-4, S-1, 5 feet

0 0 0

0 0.1 0

0.1 0 0

8.8 0.3 0.1

84.2 66.0 81.7

6.9 33.7 18.2

0.08 -- --

Drainage Design Considerations It is our understanding that drainage improvements associated with the proposed development involves the introduction of retention facilities adjacent to test pit explorations TP-2 and TP-3, respectively, with a preliminary invert elevation of ± 56 feet. Our subsurface explorations revealed that native, alluvial soils range in composition between fine sand and silty sand at the respective locations and depths. We determined a design infiltration rate for native soils underlying these proposed facilities by utilizing Method 3 of Appendix III-A of the Pierce County Stormwater and Site Development Manual (PCSSDM)(2015). This method determines a design infiltration rate by taking gradational information from sieve analyses, and inputting this data into Equation 1: log10(Ksat) = -1.57 + 1.90D10 + 0.015D60 – 0.013D90 – 2.08ffines

Where, D10, D60, and D90 are the grain sizes in mm for which 10 percent, 60 percent and 90 percent of the sample is more fine and ffines is the fraction of the soil (by weight) that passes the #200 sieve (Ksat is in cm/s). This value is further refined to produce a design infiltration rate by the application of appropriate safety factors. Safety factors, as defined by the PCSSDM, are governed by the following equation: Idesign = Imeasured x Ftesting X Fgeometry x Fplugging

Where Idesign is the maximum Design Infiltration Rate and Imeasured correlates with the Ksat

previously determined. Ftesting is a safety factor that accounts for uncertainties in the testing method and is accepted as Ftesting =0.40. Fgeometry is a safety factor that accounts for the influence of facility geometry and depth to the water table or impervious strata on the actual infiltration rate and is determined by the following equation: Fgeometry = 4 D/W + 0.05 where D = depth from the bottom of the proposed facility to the maximum wet season water table or nearest impervious layer, whichever is less and W = width of facility. Accepted range for Fgeometry is 0.25 to 1. Fplugging is a safety factor that accounts for reductions in infiltration rates over the long term due to plugging of soils. This factor is: • 0.7 for loams and sandy loams • 0.8 for fine sands and loamy sands • 0.9 for medium sands • 1.0 for coarse sands or cobbles.



After inputting the grain-size parameters into Equation 1, and applying the appropriate safety factors, we recommend utilizing a design infiltration rate of 3 inches per hour for the fine sand underlying test pit exploration TP-2, and a design infiltration rate of 0.65 inches per hour for the silty sand underlying test pit exploration TP-3. However, with an invert elevation of ± 56 feet (depth of 7 feet) for the facility adjacent to TP-2, this provides only ± 1 foot of separation from seasonally high groundwater. We recommend, if feasible, to raise the invert elevation for this facility to 57½ feet to provide more separation from groundwater, or to relocate this facility to a region with more favorable hydrogeologic conditions. Treatment Considerations As part of our evaluation, we also submitted three samples of native soils for testing to determine the cation exchange capacity (CEC) of potential treatment soils that will underlie proposed retention facilities. The following table illustrates the results of the laboratory analyses:

TABLE 3 LABORATORY TEST RESULTS FOR TREATMENT CAPACITY OF ONSITE SOILS

Soil Sample, Depth Cation Exchange Capacity (CEC)(meq/100g) TP-2, S-2, 6 feet 5.7 TP-3, S-1, 6 feet 5.5 TP-4, S-1, 5 feet 4.9

The civil engineer in charge of design should evaluate the above results to determine if native soils are adequate for treatment. Laboratory results prepared by AgSource Laboratories are attached as Appendix C. 4.0 CONCLUSIONS AND RECOMMENDATIONS Improvement plans involve construction of an early learning center within the northwest corner of the southern half of the school campus, in an area currently occupied by tennis courts and a baseball diamond. This new development will also involve the expansion of driving/parking facilities adjacent to the new structure, the introduction of several new infiltration facilities, and improvements to the athletic fields, as indicated on the attached Figure 2. The 2015 edition of the Pierce County Stormwater Management and Site Development Manual should be used for design of onsite infiltration facilities. Pierce County has adopted the 2015 IBC with local amendments for building design. We offer the following recommendations:

• Feasibility: Based on our field explorations, research, and evaluations, the proposed structures and pavements appear feasible from a geotechnical standpoint.

• Foundation Options: Due to the loose soils underlying the site, over-excavation of spread footing subgrades, to a depth of 4 feet, and the construction of structural fill bearing pads will be necessary for foundation support of the new early learning



center. If foundation construction occurs during wet conditions, it is likely that a geotextile fabric placed between bearing pads and native soils will also be necessary. Recommendations for Spread Footings are provided in Section 4.2.

• Floor Options: Floor sections should bear on medium dense or denser native soils or on properly compacted structural fill that extends down to medium dense or denser native soil. We recommend over-excavation of slab-on-grade floor subgrades to a minimum depth of 2 feet, then placement of properly compacted structural fill as a floor subbase. If floor construction occurs during wet conditions, it is likely that a geotextile fabric, placed between the structural fill floor subbase and native soils, will be necessary. Recommendations for slab-on-grade floors are included in Section 4.3. Fill underlying floor slabs should be compacted to 95 percent (ASTM:D-1557).

• Pavement Sections: After removal of any organics underlying pavements, we recommend a conventional pavement section comprised of an asphalt concrete pavement over a crushed rock base course over a properly prepared (compacted) subgrade or a granular subbase. Given the relative loose/soft soil conditions observed across the site, we recommend the over-excavation of 12 to 24 inches of the existing subgrade material underlying the proposed pavement sections and replacement with a suitable structural fill subbase.

All soil subgrades below 24 inches should be thoroughly compacted, then proof-rolled with a loaded dump truck or heavy compactor. Any localized zones of yielding subgrade disclosed during this proof-rolling operation should be over excavated to an additional maximum depth of 12 inches and replaced with a suitable structural fill material.

• Infiltration Conditions: Our subsurface explorations revealed that native, alluvial soils consist of slowly permeable silty sand at or near surface elevations, grading, in most instances, to moderately permeable, fine sand with depth. The depth of this transition typically ranges between 4 to 6 feet below existing grade. It is our understanding that drainage improvements associated with the proposed development involves the introduction of retention facilities adjacent to test pit explorations TP-2 and TP-3, respectively, with a preliminary invert elevation of ± 56 feet. We recommend utilizing a design infiltration rate of 3 inches per hour for the fine sand underlying test pit exploration TP-2, and a design infiltration rate of 0.65 inches per hour for the silty sand underlying test pit exploration TP-3. However, with an invert elevation of ± 56 feet (depth of 7 feet) for the facility adjacent to TP-2, this provides only ± 1 foot of separation from seasonally high groundwater. We recommend, if feasible, to raise the invert elevation for this facility to 57½ feet to provide more separation from groundwater, or to relocate this facility to a region with more favorable hydrogeologic conditions.



The following sections of this report present our specific geotechnical conclusions and recommendations concerning site preparation, spread footings, slab-on-grade floors, pavement, and structural fill. The Washington State Department of Transportation (WSDOT) Standard Specifications and Standard Plans cited herein refer to WSDOT publications M41-10, Standard Specifications for Road, Bridge, and Municipal Construction, and M21-01, Standard Plans for Road, Bridge, and Municipal Construction, respectively. 4.1 Site Preparation Preparation of the project site should involve erosion control, temporary drainage, clearing, stripping, excavations, cutting, subgrade compaction, and filling. Erosion Control: Before new construction begins, an appropriate erosion control system should be installed. This system should collect and filter all surface water runoff through silt fencing. We anticipate a system of berms and drainage ditches around construction areas will provide an adequate collection system. Silt fencing fabric should meet the requirements of WSDOT Standard Specification 9-33.2 Table 3. In addition, silt fencing should embed a minimum of 6 inches below existing grade. An erosion control system requires occasional observation and maintenance. Specifically, holes in the filter and areas where the filter has shifted above ground surface should be replaced or repaired as soon as they are identified. Temporary Drainage: We recommend intercepting and diverting any potential sources of surface or near-surface water within the construction zones before stripping begins. Because the selection of an appropriate drainage system will depend on the water quantity, season, weather conditions, construction sequence, and contractor's methods, final decisions regarding drainage systems are best made in the field at the time of construction. Based on our current understanding of the construction plans, surface and subsurface conditions, we anticipate that curbs, berms, or ditches placed around the work areas will adequately intercept surface water runoff. Clearing and Stripping: After surface and near-surface water sources have been controlled, sod, topsoil, and root-rich soil should be stripped from the site. Our explorations and field observations indicate that the topsoil horizon is upwards of 9 inches thick across the project area. Site Excavations: Based on our explorations, we expect that excavations will encounter poorly consolidated alluvial soils which can be easily excavated using standard excavation equipment. Dewatering: Groundwater seepage was encountered in four of test pit explorations, at depths ranging between 5½ to 10 feet below existing grade. At other locations within the proposed improvement area, we anticipate that groundwater is within 12 feet of existing grade. If groundwater is encountered in excavations above the water table, or slightly below, we anticipate that an internal system of ditches, sumpholes, and pumps will be adequate to temporarily dewater shallow excavations. For excavations significantly below the water table, we anticipate that expensive dewatering equipment, such as well points, will be required to temporarily dewater excavations.



Temporary Cut Slopes: All temporary soil slopes associated with site cutting or excavations should be adequately inclined to prevent sloughing and collapse. Temporary cut slopes in site soils should be no steeper than 1½H:1V, and should conform to Washington Industrial Safety and Health Act (WISHA) regulations. Subgrade Compaction: Exposed subgrades for the foundations of the planned structures should be compacted to a firm, unyielding state before new concrete or fill soils are placed. Any localized zones of looser granular soils observed within a subgrade should be compacted to a density commensurate with the surrounding soils. In contrast, any organic, soft, or pumping soils observed within a subgrade should be over-excavated and replaced with a suitable structural fill material. Site Filling: Our conclusions regarding the reuse of onsite soils and our comments regarding wet-weather filling are presented subsequently. Regardless of soil type, all fill should be placed and compacted according to our recommendations presented in the Structural Fill section of this report. Specifically, building pad fill soil should be compacted to a uniform density of at least 95 percent (based on ASTM:D-1557). Onsite Soils: We offer the following evaluation of these onsite soils in relation to potential use as structural fill:

• Surficial Organic Soil and Organic-Rich Topsoil: Where encountered, surficial organic soils, like duff, topsoil, root-rich soil, and organic-rich fill soils are not suitable for use as structural fill under any circumstances, due to high organic content. Consequently, this material can be used only for non-structural purposes, such as in landscaping areas.

• Alluvial Soils: Our subsurface explorations encountered alluvial soils underlying the project area, varying in composition from fine sand to silt. Cleaner, well-drained sandy soils encountered beneath much of the improvement area below a depth of 6 feet can be adequately reused as structural fill under most weather conditions due to its low relative fines (percent silt and clay) content. The more prominent, fine-grained soils onsite, are more poorly-drained, and will be difficult, if not impossible to reuse under wet weather conditions.

Permanent Slopes: All permanent cut slopes and fill slopes should be adequately inclined to reduce long-term raveling, sloughing, and erosion. We generally recommend that no permanent slopes be steeper than 2H:1V. For all soil types, the use of flatter slopes (such as 2½H:1V) would further reduce long-term erosion and facilitate revegetation. Slope Protection: We recommend that a permanent berm, swale, or curb be constructed along the top edge of all permanent slopes to intercept surface flow. Also, a hardy vegetative groundcover should be established as soon as feasible, to further protect the slopes from runoff water erosion. Alternatively, permanent slopes could be armored with quarry spalls or a geosynthetic erosion mat.



4.2 Spread Footings In our opinion, conventional spread footings will provide adequate support for the proposed structure if the subgrade is properly prepared. Due to the soft soils underlying the site, over-excavation of spread footing subgrades, to a depth of 4 feet, and the construction of structural fill bearing pads will be necessary for foundation support of the new early learning center. Footing Depths and Widths: For frost and erosion protection, the bases of all exterior footings should bear at least 18 inches below adjacent outside grades, whereas the bases of interior footings need bear only 12 inches below the surrounding slab surface level. To reduce post-construction settlements, continuous (wall) and isolated (column) footings should be at least 16 and 24 inches wide, respectively. Bearing Subgrades: Structural fill bearing pads, 3 feet thick and compacted to a density of at least 95 percent (based on ASTM:D-1557), should underlie spread footings on this site. If foundation construction occurs during wet conditions, it is possible that a geotextile fabric, placed between the bearing pad and native soils, will be necessary. In general, before footing concrete is placed, any localized zones of loose soils exposed across the footing subgrades should be compacted to a firm, unyielding condition, and any localized zones of soft, organic, or debris-laden soils should be overexcavated and replaced with suitable structural fill. Lateral Overexcavations: Because foundation stresses are transferred outward as well as downward into the bearing soils, all structural fill placed under footings, should extend horizontally outward from the edge of each footing. This horizontal distance should be equal to the depth of placed fill. Therefore, placed fill that extends 4 feet below the footing base should also extend 4 feet outward from the footing edges. Subgrade Observation: All footing subgrades should consist of firm, unyielding, native soils, or structural fill materials that have been compacted to a density of at least 95 percent (based on ASTM:D-1557). Footings should never be cast atop loose, soft, or frozen soil, slough, debris, existing uncontrolled fill, or surfaces covered by standing water. Bearing Pressures: In our opinion, for static loading, footings that bear on properly prepared, structural fill bearing pads 4 feet thick can be designed for an allowable soil bearing pressure of 2,000 psf. A one-third increase in allowable soil bearing capacity may be used for short-term loads created by seismic or wind related activities. Footing Settlements: Assuming that structural fill soils are compacted to a medium dense or denser state, we estimate that total post-construction settlements of properly designed footings bearing on properly prepared subgrades will not exceed 1 inch. Differential settlements for comparably loaded elements may approach one-half of the actual total settlement over horizontal distances of approximately 50 feet.



Footing Backfill: To provide erosion protection and lateral load resistance, we recommend that all footing excavations be backfilled on both sides of the footings and stemwalls after the concrete has cured. Either imported structural fill or non-organic onsite soils can be used for this purpose, contingent on suitable moisture content at the time of placement. Regardless of soil type, all footing backfill soil should be compacted to a density of at least 90 percent (based on ASTM:D-1557). Lateral Resistance: Footings that have been properly backfilled as recommended above will resist lateral movements by means of passive earth pressure and base friction. We recommend using an allowable passive earth pressure of 225 psf and an allowable base friction coefficient of 0.35 for site soils. 4.3 Slab-On-Grade Floors In our opinion, soil-supported slab-on-grade floors can be used if the subgrades are properly prepared. We offer the following comments and recommendations concerning slab-on-grade floors. Floor Subbase: We recommend over-excavation of slab-on-grade floor subgrades to a minimum depth of 2 feet, then placement of properly compacted structural fill as a floor subbase. If floor construction occurs during wet conditions, it is likely that a geotextile fabric, placed between the structural fill floor subbase and native soils, will be necessary. All subbase fill should be compacted to a density of at least 95 percent (based on ASTM:D-1557). Capillary Break and Vapor Barrier: To retard the upward wicking of moisture beneath the floor slab, we recommend that a capillary break be placed over the subgrade. Ideally, this capillary break would consist of a 4-inch-thick layer of pea gravel or other clean, uniform, well-rounded gravel, such as “Gravel Backfill for Drains” per WSDOT Standard Specification 9-03.12(4), but clean angular gravel can be used if it adequately prevents capillary wicking. In addition, a layer of plastic sheeting (such as Crosstuff, Visqueen, or Moistop) should be placed over the capillary break to serve as a vapor barrier. During subsequent casting of the concrete slab, the contractor should exercise care to avoid puncturing this vapor barrier. Vertical Deflections: Due to elastic compression of subgrades, soil-supported slab-on-grade floors can deflect downwards when vertical loads are applied. In our opinion, a subgrade reaction modulus of 250 pounds per cubic inch can be used to estimate such deflections. 4.4 Drainage Systems In our opinion, the proposed early learning center should be provided with a permanent drainage system to reduce the risk of future moisture problems. We offer the following recommendations and comments for drainage design and construction purposes. Perimeter Drains: We recommend that the residence be encircled with a perimeter drain system to collect seepage water. This drain should consist of a 4-inch-diameter perforated pipe within



an envelope of pea gravel or washed rock, extending at least 6 inches on all sides of the pipe, and the gravel envelope should be wrapped with filter fabric to reduce the migration of fines from the surrounding soils. Ideally, the drain invert would be installed no more than 8 inches above the base of the perimeter footings. Subfloor Drains: We recommend that subfloor drains be included beneath the new building. These subfloor drains should consist of 4-inch-diameter perforated pipes surrounded by at least 6 inches of pea gravel and enveloped with filter fabric. A pattern of parallel pipes spaced no more than 20 feet apart and having inverts located about 12 inches below the capillary break layer would be appropriate, in our opinion. Discharge Considerations: If possible, all perimeter drains should discharge to a sewer system or other suitable location by gravity flow. Check valves should be installed along any drainpipes that discharge to a sewer system to prevent sewage backflow into the drain system. If gravity flow is not feasible, a pump system is recommended to discharge any water that enters the drainage system. Runoff Water: Roof-runoff and surface-runoff water should not discharge into the perimeter drain system. Instead, these sources should discharge into separate tightline pipes and be routed away from the building to a storm drain or other appropriate location. Grading and Capping: Final site grades should slope downward away from the buildings so that runoff water will flow by gravity to suitable collection points, rather than ponding near the building. Ideally, the area surrounding the building would be capped with concrete, asphalt, or low-permeability (silty) soils to minimize or preclude surface-water infiltration. 4.5 Asphalt Pavement Since asphalt pavements will be expanded during the course of the proposed development, we offer the following comments and recommendations for pavement design and construction. Subgrade Preparation: After removal of any organics underlying pavements, we recommend a conventional pavement section comprised of an asphalt concrete pavement over a crushed rock base course over a properly prepared (compacted) subgrade or a granular subbase. Given the relative loose/soft soil conditions observed across the site, we recommend the over-excavation of 12 inches of the existing subgrade material underlying the proposed pavement sections and replacement with a suitable structural fill subbase, provided the exposed subgrade can be thoroughly compacted to a uniform dense condition. If this is not feasible, the overexcavation depth should be increased to 24 inches. Given the extent of the proposed paving operation and corresponding earthwork activities, we recommend limiting the subgrade preparation to times of dry weather. All prepared soil subgrades should be thoroughly compacted, then proof-rolled with a loaded dump truck or heavy compactor. Any localized zones of yielding subgrade disclosed during this proof-rolling operation should be over excavated and repaired using a suitable structural fill



material. All structural fill should be compacted according to our recommendations given in the Structural Fill section. Specifically, the upper 2 feet of soils underlying pavement section should be compacted to at least 95 percent (based on ASTM D-1557). Pavement Materials: For the base course, we recommend using imported crushed rock, such as "Crushed Surfacing Top Course” per WSDOT Standard Specification 9-03.9(3). If a subbase course is needed, we recommend using imported, clean, well-graded sand and gravel such as “Ballast” or “Gravel Borrow” per WSDOT Standard Specifications 9-03.9(1) and 9-03.14, respectively. Conventional Asphalt Sections: A conventional pavement section typically comprises an asphalt concrete pavement over a crushed rock base course. We recommend using the following conventional pavement sections:

Minimum Thickness Pavement Course Parking Areas High Traffic and Bus Loop Areas Asphalt Concrete Pavement 2 inches 4 inches Crushed Rock Base 4 inches 8 inches Granular Fill Subbase (if needed) 24 inches 24 inches

Compaction and Observation: All subbase and base course material should be compacted to at least 95 percent of the Modified Proctor maximum dry density (ASTM D-1557), and all asphalt concrete should be compacted to at least 92 percent of the Rice value (ASTM D-2041). We recommend that an MGI representative be retained to observe the compaction of each course before any overlying layer is placed. For the subbase and pavement course, compaction is best observed by means of frequent density testing. For the base course, methodology observations and hand-probing are more appropriate than density testing. Pavement Life and Maintenance: No asphalt pavement is maintenance-free. The above described pavement sections present our minimum recommendations for an average level of performance during a 20-year design life, therefore, an average level of maintenance will likely be required. Furthermore, a 20-year pavement life typically assumes that an overlay will be placed after about 10 years. Thicker asphalt and/or thicker base and subbase courses would offer better long-term performance, but would cost more initially; thinner courses would be more susceptible to “alligator” cracking and other failure modes. As such, pavement design can be considered a compromise between a high initial cost and low maintenance costs versus a low initial cost and higher maintenance costs.



4.6 Structural Fill The term "structural fill" refers to any material placed under foundations, retaining walls, slab-on-grade floors, sidewalks, pavements, and other structures. Our comments, conclusions, and recommendations concerning structural fill are presented in the following paragraphs. Materials: Typical structural fill materials include clean sand, gravel, pea gravel, washed rock, crushed rock, well-graded mixtures of sand and gravel (commonly called "gravel borrow" or "pit-run"), and miscellaneous mixtures of silt, sand, and gravel. Recycled asphalt, concrete, and glass, which are derived from pulverizing the parent materials, are also potentially useful as structural fill in certain applications. Utilizing recycled content may require approval from the Tacoma Pierce County Health Department for placement in an aquifer recharge area. Soils used for structural fill should not contain any organic matter or debris, nor any individual particles greater than about 6 inches in diameter. Fill Placement: Clean sand, gravel, crushed rock, soil mixtures, and recycled materials should be placed in horizontal lifts not exceeding 8 inches in loose thickness, and each lift should be thoroughly compacted with a mechanical compactor. Compaction Criteria: Using the Modified Proctor test (ASTM:D-1557) as a standard, we recommend that structural fill used for various onsite applications be compacted to the following minimum densities:

Fill Application Minimum

Compaction Footing subgrade and bearing pad Foundation backfill Asphalt pavement base Asphalt pavement subgrade (upper 2 feet) Asphalt pavement subgrade (below 2 feet)

95 percent 90 percent 95 percent 95 percent 90 percent

Subgrade Observation and Compaction Testing: Regardless of material or location, all structural fill should be placed over firm, unyielding subgrades prepared in accordance with the Site Preparation section of this report. The condition of all subgrades should be observed by geotechnical personnel before filling or construction begins. Also, fill soil compaction should be verified by means of in-place density tests performed during fill placement so that adequacy of soil compaction efforts may be evaluated as earthwork progresses. Soil Moisture Considerations: The suitability of soils used for structural fill depends primarily on their grain-size distribution and moisture content when they are placed. As the "fines" content (that soil fraction passing the U.S. No. 200 Sieve) increases, soils become more sensitive to small changes in moisture content. Soils containing more than about 5 percent fines (by weight) cannot be consistently compacted to a firm, unyielding condition when the moisture content is more than 2 percentage points above or below optimum. For fill placement during wet-weather site work, we recommend using "clean" fill, which refers to soils that have a fines content of 5 percent or less (by weight) based on the soil fraction passing the U.S. No. 4 Sieve.

Proposed Sumner MS Improvements11508 Willow StreetSumner, Washington

Topographic and Location Map

FIGURE 1P878-T17

APPROXIMATE SITE LOCATION

Migizi Group, Inc.P.O. Box 44840

Tacoma, WA 98448

APPENDIX A SOIL CLASSIFICATION CHART AND

KEY TO TEST DATA

LOG OF TEST PITS

CLAYEY GRAVELS, POORLY GRADED GRAVEL-SAND-CLAYMIXTURES

SILTS AND CLAYS

CO

AR

SE

GR

AIN

ED

SO

ILS

Mor

e th

an H

alf >

#20

0 si

eve

LIQUID LIMIT LESS THAN 50

LIQUID LIMIT GREATER THAN 50

CLEAN GRAVELSWITH LITTLE ORNO FINES

GRAVELS WITHOVER 15% FINES

CLEAN SANDSWITH LITTLEOR NO FINES

MORE THAN HALFCOARSE FRACTIONIS SMALLER THANNO. 4 SIEVE

MORE THAN HALFCOARSE FRACTIONIS LARGER THANNO. 4 SIEVE

INORGANIC SILTS, MICACEOUS OR DIATOMACIOUS FINESANDY OR SILTY SOILS, ELASTIC SILTS

ORGANIC CLAYS AND ORGANIC SILTY CLAYS OF LOWPLASTICITY

OH

INORGANIC SILTS AND VERY FINE SANDS, ROCK FLOUR,SILTY OR CLAYEY FINE SANDS, OR CLAYEY SILTS WITHSLIGHT PLASTICITY

CH

SILTY GRAVELS, POORLY GRADED GRAVEL-SAND-SILTMIXTURES

SANDS

SILTS AND CLAYS

Figure A-1

INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY,GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS,LEAN CLAYS

R-Value

Sieve Analysis

Swell Test

Cyclic Triaxial

Unconsolidated Undrained Triaxial

Torvane Shear

Unconfined Compression

(Shear Strength, ksf)

Wash Analysis

(with % Passing No. 200 Sieve)

Water Level at Time of Drilling

Water Level after Drilling(with date measured)

RV

SA

SW

TC

TX

TV

UC

(1.2)

WA

(20)

Modified California

Split Spoon

Pushed Shelby Tube

Auger Cuttings

Grab Sample

Sample Attempt with No Recovery

Chemical Analysis

Consolidation

Compaction

Direct Shear

Permeability

Pocket Penetrometer

CA

CN

CP

DS

PM

PP

PtHIGHLY ORGANIC SOILS

TYPICAL NAMES

GRAVELS

ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,ORGANIC SILTS

WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES

MAJOR DIVISIONS

PEAT AND OTHER HIGHLY ORGANIC SOILS

WELL GRADED SANDS, GRAVELLY SANDS

POORLY GRADED SANDS, GRAVELLY SANDS

SILTY SANDS, POOORLY GRADED SAND-SILT MIXTURES

CLAYEY SANDS, POORLY GRADED SAND-CLAY MIXTURES

POORLY GRADED GRAVELS, GRAVEL-SAND MIXTURES

SOIL CLASSIFICATION CHART AND KEY TO TEST DATA

GW

GP

GM

GC

SW

SP

SM

SC

ML

FIN

E G

RA

INE

D S

OIL

SM

ore

than

Hal

f < #

200

siev

e

LGD

A N

NN

N02

GIN

T U

S L

AB

.GP

J

11/4

/05

INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS

CL

OL

MH

SANDS WITHOVER 15% FINES

Jessica

Typewritten Text

Jessica

Typewritten Text

Jessica

Typewritten Text

Jessica

Typewritten Text

Jessica

Typewritten Text

Jessica

Typewritten Text

Migizi Group, Inc.

Jessica

Typewritten Text

Jessica

Typewritten Text

Jessica

Sticky Note

Completed set by Jessica

Jessica

Sticky Note

Accepted set by Jessica

Jessica

Placed Image

GBS-1

GBS-2

ML

SM

SP-SM

ML

0.8

3.5

4.5

6.5

7.5

Sod and topsoil

(ML) Gray/brown mottled sandy silt (soft, moist)

(SM) Gray fine silty sand (loose, wet)

(SP-SM) Blue/gray fine to medium sand with silt and interbeds of silty sand (loose, wet)

(ML) Light brown silt with buried logs (stiff, moist)

Severe caving observed from 4 to 7.5 feetVery rapid groundwater seepage observed at 5.5 feet

The depths on the test pit logs are based on an average of measurements across the test pit and should beconsidered accurate to 0.5 foot.

Bottom of test pit at 7.5 feet.

NOTES

LOGGED BY ZLL

EXCAVATION METHOD Rubber Tracked Mini Excavator

EXCAVATION CONTRACTOR Paulman GROUND WATER LEVELS:

CHECKED BY JEB

DATE STARTED 2/18/17 COMPLETED 2/18/17

AT TIME OF EXCAVATION 5.50 ft Very rapid seepage

AT END OF EXCAVATION ---

AFTER EXCAVATION ---

TEST PIT SIZEGROUND ELEVATION

SA

MP

LE T

YP

EN

UM

BE

R

DE

PT

H(f

t)

0.0

2.5

5.0

7.5

PAGE 1 OF 1Figure A-2

TEST PIT NUMBER TP-1

CLIENT Sumner School District No. 320

PROJECT NUMBER P878-T17

PROJECT NAME Proposed Sumner Middle School Improvements

PROJECT LOCATION 11508 Willow Street, Sumner, WA

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Migizi Group, Inc.PO Box 44840Tacoma, WA 98448Telephone: 253-537-9400Fax: 253-537-9401

U.S

.C.S

.

GR

AP

HIC

LOG

MATERIAL DESCRIPTION

GBS-1

GBS-2

SP

SM

SP-SM

0.3

0.8

5.5

9.0

Sod and topsoil(SP) Gray fine to medium sand (loose, moist) (Sand Drainage Blanket)

(SM) Brown fine silty sand (medium dense, moist)

(SP-SM) Dark gray fine sand with silt (loose, moist)

Severe caving observed from 5 to 9 feetSlow groundwater seepage observed at 8 feet



NOTES

LOGGED BY ZLL



CHECKED BY JEB


AT TIME OF EXCAVATION 8.00 ft Slow seepage




SA

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U.S

.C.S

.

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AP

HIC

LOG


GBS-1

SP-SM

SM

SM

0.7

4.0

10.0

(SP-SM) Gray/brown fine to medium sand with silt (loose, wet) (Playfield Mix)

(SM) Light brown fine silty sand (medium dense, moist)

(SM) Gray/brown fine silty sand (loose, moist)

Severe caving observed from 4 to 10 feetNo groundwater seepage observed



NOTES

LOGGED BY ZLL



CHECKED BY JEB


AT TIME OF EXCAVATION ---




SA

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H(f

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5.0

7.5

10.0







CO

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U.S

.C.S

.

GR

AP

HIC

LOG


GBS-1

SP-SM

SM

SP

SM

0.6

3.5

4.0

10.0

(SP-SM) Gray/brown fine to medium sand with silt (loose, wet) (Playfield Mix)


(SP) Blue/gray fine to medium sand with gravel (medium dense, moist)





NOTES

LOGGED BY ZLL



CHECKED BY JEB






SA

MP

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YP

EN

UM

BE

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DE

PT

H(f

t)

0.0

2.5

5.0

7.5

10.0







CO

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U.S

.C.S

.

GR

AP

HIC

LOG


GBS-1

GBS-2

SM

SP-SM

SP

0.3

3.0

5.0

9.0

Sod and topsoil(SM) Light brown fine silty sand (medium dense, moist)

(SP-SM) Gray/brown fine sand with silt (loose, moist)

(SP) Dark gray fine sand (loose, moist)




NOTES

LOGGED BY ZLL



CHECKED BY JEB






SA

MP

LE T

YP

EN

UM

BE

R

DE

PT

H(f

t)

0.0

2.5

5.0

7.5







CO

PY

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U.S

.C.S

.

GR

AP

HIC

LOG


GBS-1

SM

SP

0.6

4.0

9.0

Sod and topsoil


(SP) Dark gray fine to medium sand (loose, moist)

No caving observedNo groundwater seepage observed



NOTES

LOGGED BY ZLL



CHECKED BY JEB






SA

MP

LE T

YP

EN

UM

BE

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DE

PT

H(f

t)

0.0

2.5

5.0

7.5







CO

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U.S

.C.S

.

GR

AP

HIC

LOG


GBS-1

GBS-2

SP

SM

SP-SM

SP

0.4

0.8

3.5

5.5

9.0

Sod and topsoil

(SP) Gray fine to medium sand (loose, moist) (Sand Drainage Blanket)

(SM) Brown fine silty sand (medium dense, moist)

(SP-SM) Gray/brown fine sand with silt (loose, moist)

(SP) Gray fine sand (medium dense, moist)

No caving observedSlow groundwater seepage observed at 8 feet



NOTES

LOGGED BY ZLL



CHECKED BY JEB






SA

MP

LE T

YP

EN

UM

BE

R

DE

PT

H(f

t)

0.0

2.5

5.0

7.5







CO

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U.S

.C.S

.

GR

AP

HIC

LOG


GBS-1

SM

SP-SM

SM

SM

SP-SM

0.6

2.5

3.0

5.0

8.0

10.5

Sod and topsoil

(SM) Gray/brown mottled fine silty sand (soft, wet)

(SP-SM) Gray fine to medium sand with silt (loose, moist)

(SM) Gray/brown mottled fine silty sand (medium dense, moist)


(SP-SM) Dark gray fine sand with silt (medium dense, moist)

No caving observedSlow groundwater seepage observed at 10 feet



NOTES

LOGGED BY ZLL

EXCAVATION METHOD Rubber Tired Backhoe

EXCAVATION CONTRACTOR Owner-Operator GROUND WATER LEVELS:

CHECKED BY JEB






SA

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U.S

.C.S

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HIC

LOG


APPENDIX B LABORATORY TESTING RESULTS

Job Name: Sumner Middle School ImprovementsJob Number: P878-T17

Tested By: ZLLDate: 2/26/17

Boring #: TP-2Sample #: 2

Depth: 6 feet

Moisture Content (%) 11.0%

Sieve Size Percent Passing (%) Size Fraction Percent By

Weight

3.0 in. (75.0) 100.0 Coarse Gravel1.5 in. (37.5) 100.0 Fine Gravel3/4 in. (19.0) 100.03/8 in. (9.5-mm) 100.0 Coarse Sand 0.1No. 4 (4.75-mm) 100.0 Medium Sand 8.8No. 10 (2.00-mm) 99.9 Fine Sand 84.2No. 20 (.850-mm) 99.4No. 40 (.425-mm) 91.1 Fines 6.9No. 60 (.250-mm) 59.8 Total 100.0No. 100 (.150-mm) 24.7No. 200 (.075-mm) 6.9

LLPI

D10 0.08D30 0.16D60 0.25

Cc 1.24Cu 2.97

Group Name Grayish-brown poorly graded sand with silt Symbol (SP-SM) (loose, moist)

Figure B-1

Soil Classification Data Sheet

Particle Size Analysis Summary Data

ASTM Classification

Sample Distribution Job Name: Sumner Middle School ImprovemeSample #: 2Job Number: P878-T17 Date: 2/26/17

Figure: B-2 Tested By: ZLL Depth: 6 feetExploration #: TP-2

0

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0.0010.010.11101001000

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Particle Size (mm)

Sample Distribution

Sample DistributionU.S. Standard Sieve Sizes

3" 1.5" 3/4" 3/8" 4 10 4020 60 100 200




Depth: 6 feet



Weight

3.0 in. (75.0) 100.0 Coarse Gravel1.5 in. (37.5) 100.0 Fine Gravel 0.13/4 in. (19.0) 100.03/8 in. (9.5-mm) 100.0 Coarse Sand 0.0No. 4 (4.75-mm) 99.9 Medium Sand 0.3No. 10 (2.00-mm) 99.9 Fine Sand 66.0No. 20 (.850-mm) 99.8No. 40 (.425-mm) 99.7 Fines 33.7No. 60 (.250-mm) 98.7 Total 100.0No. 100 (.150-mm) 83.7No. 200 (.075-mm) 33.7

LLPI

D10D30D60 0.11

CcCu

Group Name Grayish-brown silty sand Symbol (SM) (loose, moist)

Figure B-3



ASTM Classification



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0.0010.010.11101001000

Perc

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Particle Size (mm)

Sample Distribution


3" 1.5" 3/4" 3/8" 4 10 4020 60 100 200




Depth: 5 feet



Weight

3.0 in. (75.0) 100.0 Coarse Gravel1.5 in. (37.5) 100.0 Fine Gravel3/4 in. (19.0) 100.03/8 in. (9.5-mm) 100.0 Coarse Sand 0.0No. 4 (4.75-mm) 100.0 Medium Sand 0.1No. 10 (2.00-mm) 100.0 Fine Sand 81.7No. 20 (.850-mm) 99.9No. 40 (.425-mm) 99.8 Fines 18.2No. 60 (.250-mm) 97.7 Total 100.0No. 100 (.150-mm) 57.5No. 200 (.075-mm) 18.2

LLPI

D10D30 0.09D60 0.15

CcCu

Group Name Grayish-brown silty sand Symbol (SM) (loose, moist)

Figure B-5



ASTM Classification



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0.0010.010.11101001000

Perc

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ng

Particle Size (mm)

Sample Distribution


3" 1.5" 3/4" 3/8" 4 10 4020 60 100 200

APPENDIX C AGSOURCE LABORATORIES CATION

EXCHANGE CAPACITY RESULTS

Analysis ResultClient Sample Identification

REPORT OF ANALYTICAL RESULTS

Soil Analysis

Date Received Date Reported Information Sheet #

Laboratory Sample #Submitted For:Submitted By:

S337824-Mar-201713-Mar-2017

44840

TACOMA, WASHINGTON 98448

MIGIZI GROUP, INC.

UMM00111

BA14366 - BA14368

323 Sixth Street

Umatilla, OR 97882

Tel:541-922-4894

[email protected]

TP-2,S-25.7 Meq/100gActual CEC



DISCLAIMER: Data and information in this report are intended solely for the individual(s) for whom samples were submitted.

Reproduction of this report must be in its entirety. Levels listed are guidelines only. Data was reported based on standard laboratory

procedures and deviations. Page 1 of 1

geotechnical engineering report€¦ · geotechnical engineering report p878-t17 migizi group, inc....

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