Geotechnical Engineering Services

Maritime Security Operations Center Tacoma, Washington

for Reid Middleton, Inc.

July 3, 2012

Earth Science + Technology

Geotechnical Engineering Services

Maritime Security Operations Center Tacoma, Washington

for Reid Middleton, Inc.

July 3, 2012

1101 South Fawcett Avenue, Suite 200 Tacoma, Washington 98402 253.383.4940

Table of Contents

INTRODUCTION ...... 1 PROJECT UNDERSTANDING ...... 1 SEISMIC DESIGN APPROACH ...... 1 GEOTECHNICAL SCOPE OF SERVICES ...... 1 SITE CONDITIONS ...... 3 Surface Conditions ...... 3 Published Geology ...... 3 Subsurface Explorations ...... 3 Subsurface Conditions ...... 4 General ...... 4 Groundwater ...... 4 Discussion ...... 4 SEISMIC DESIGN CONSIDERATIONS ...... 5 General ...... 5 Seismic Design Parameters ...... 5 ASCE 41 and ASCE 7/IBC Seismic Design Criteria ...... 5 Liquefaction ...... 5 General ...... 5 Liquefaction Analysis ...... 6 Liquefaction-Induced Settlement ...... 6 Liquefied Soil Strength Parameters ...... 6 Lateral Spreading ...... 6 SEISMIC SLOPE DEFORMATION MITIGATION ASSESSMENT ...... 7 General ...... 7 Compaction Grout Columns ...... 7 Slope Stability and Newmark Analyses ...... 7 Slope Stability Analysis Methodology...... 8 Slope Stability Analysis Results ...... 9 Existing Conditions ...... 9 Improved Ground Condition ...... 9 CONCLUSIONS AND RECOMMENDATIONS ...... 10 General ...... 10 Site Development and Earthwork ...... 10 General ...... 10 Subgrade Preparation ...... 11 Wet Weather Construction ...... 11 Fill Materials ...... 11 Fill Placement and Compaction ...... 12 Shallow Foundation Support of Apparatus Bay...... 12 Spread Footings ...... 12

July 3, 2012 | Page i File No. 0570-113-01 Slabs-on-Grade ...... 12 Lateral Load Resistance for Shallow Foundations...... 13 Pile Design Considerations ...... 13 General ...... 13 Axial Pile Capacity ...... 14 Settlement ...... 14 Lateral Pile Performance ...... 14 Pile Installation Considerations ...... 15 LIMITATIONS ...... 15

LIST OF FIGURES Figure 1. Vicinity Map Figure 2. Site Plan Figures 3 and 4. SLOPE/W Analysis Figure 5. Compaction Grouting Site Plan Figures 6 and 7. SLOPE/W Analysis Figure 8. Allowable Axial Pile Capacity 18 inch Pipe Piles Figure 9. Allowable Axial Pile Capacity 12.75 inch Pipe Piles Figures 10 through 24. Lateral Pile Analysis

APPENDICES Appendix A. Subsurface Explorations and Laboratory Testing Figure A-1. Key to Exploration Logs Figure A-2. Log of Boring Figure A-3. Sieve Analysis Results Appendix B. Report Limitations and Guidelines for Use

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INTRODUCTION

This report presents the results of our geotechnical engineering services in support of the proposed Maritime Security Operations Center in Tacoma, Washington. The project site is located at 3301 Ruston Way in Tacoma, Washington. The approximate location of the site is shown on the Vicinity Map, Figure 1. Our services have been provided in general accordance with our agreement with Reid Middleton, Inc. signed May 13, 2011 and our additional scope and fee estimate, dated April 5, 2012 and approved by Reid Middleton on June 5, 2012.

PROJECT UNDERSTANDING

Our understanding of the project is based on our discussions with the design team, our review of the conceptual drawings and the “Evaluation and Concept Retrofit Design” letter dated August 18, 2010 by Reid Middleton, Inc. and our local project experience. The proposed improvements are part of a plan to convert the existing Fire Station No. 5 complex into a joint Maritime Security Operations Center. The existing Fire Station No. 5 complex comprises a timber pile supported pier and timber pile supported fire station structure. The existing pier extends approximately 180 feet offshore. A Site Plan showing existing site features is included as Figure 2.

Specific improvements include: 1) new floating moorage for response vessels located approximately 115 feet beyond the end of the existing pier, 2) a seismic upgrade of the existing pier and existing fire station structure, 3) a new upland apparatus bay for emergency service vehicles and 4) general site improvements for vehicle and pedestrian circulation. Driven piles are planned for foundation support of the proposed overwater improvements.

SEISMIC DESIGN APPROACH

Based on project team discussions, we understand that two seismic codes are being considered for design of the proposed improvements: 1) American Society of Civil Engineers (ASCE) 41-06 for the seismic upgrade of the existing structure and 2) ASCE 7-05/2009 International Building Code (IBC) for the new upland apparatus bay. This includes evaluating three design earthquake levels: the 2,475-year, 475-year and 2/3 of the 2,475-year return period events. We used map-based methods to classify the site in general accordance with the referenced codes. Our agreed scope did not include a site-specific response evaluation because of budget constraints.

GEOTECHNICAL SCOPE OF SERVICES

The purpose of our services for this project was to explore the site subsurface conditions as a basis for developing geotechnical recommendations in support of design and construction. Our geotechnical scope of services included:

1. Reviewing published geologic information for the site and information provided by others, such as existing seismic reports and pile driving records and surveys for the area.

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2. Contacting the Washington Utilities Coordinating Council, “One Call” service to locate utilities in the project area. We also coordinated utility locations with the design team and City of Tacoma. 3. Drilling an on-land boring to a depth of approximately 81½ feet below ground surface (bgs) using subcontracted drilling services. 4. Completing laboratory tests on selected samples recovered from the boring. Our laboratory testing program included grain-size distribution and percent fines determinations. 5. Performing shallow hand tool explorations along mudline at low tide to help estimate the thickness of loose/soft overburden soils. We attempted to advance three probes, using a dynamic cone penetrometer (DCP). 6. Characterizing the subsurface conditions at the site based on results of the field exploration and laboratory testing programs. 7. Classifying the Seismic Site Class and profile definition using map-based methods in general accordance with ASCE 41-06 and ASCE 7-05/2009 IBC. This includes evaluating three nominal earthquake levels: the 2,475-year, 475-year and 2/3 of the 2,475-year return period events. 8. Providing our opinion regarding possible outcomes resulting from earthquake ground motions such as: 1) slope instability/lateral spreading, 2) liquefaction and 3) surface rupture. We provide estimates of liquefaction-induced settlement based on semi-empirical methods. 9. Developing preliminary recommendations for driven pile design and installation. We provide allowable downward and upward capacities for two selected pile types. We also performed LPILE analyses for the structure and float piles. 10. Providing our opinions regarding the need for offshore explorations and/or a test pile program. Based on project team discussions, we understand the upland apparatus bay will be supported on shallow foundations and will likely incorporate a slab-on-grade floor. Although it was not explicitly included in our scope of services, we provide recommendations for shallow spread footings and slabs-on-grade, as requested.

In accordance with our additional scope and fee estimate, dated April 5, 2012 and approved by Reid Middleton on June 5, 2012, we also provided the following services:

11. Developing a compaction grouting ground improvement program to reduce the liquefaction- related settlement and lateral spreading hazards present at the site under the design earthquakes. 12. Completing soil liquefaction and global slope stability analyses considering the effects of the compaction grouting program to evaluate performance of the design. Stability analyses were completed using limit equilibrium methods. 13. Working with Reid Middleton to develop project drawings and specifications for the compaction grouting program.

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SITE CONDITIONS

Surface Conditions The site is located along Ruston Way, on a fill prism that extends about 150 feet northwest into Commencement Bay. The ground surface in the upland fill area is generally flat and varies between approximately Elevation 17 and 18 feet mean lower low water (MLLW). The existing shoreline fill slope varies between about 2H:1V (horizontal:vertical) and 2.5H:1V, extends to about Elevation 0 feet MLLW, and is surfaced with riprap slope protection. Beyond the fill slope, the ground surface dips at about 5H:1V to 6H:1V.

The upland portion of the site consists of asphalt concrete parking areas and landscaped areas. Adjacent properties are occupied by waterfront restaurants constructed on timber pile supported docks. The ground surface to the southwest of Ruston Way forms a bluff extending upward to about Elevation 100 feet MLLW.

Published Geology The Geologic Map of the Tacoma North 7.5-minute Quadrangle, Washington (Troost and Booth, in review) indicates the site is underlain by artificial fill (af) and tideflat deposits (Qtf). The bluff to the southwest of the project site is mapped from top to bottom as Vashon recessional outwash (Qvr), over Vashon advance outwash (Qva) and pre-Fraser sediments (Qpf). The following provides a brief summary description of each soil unit, in stratigraphic order:

■ Artificial Fill (af) - a variable complex of gravel, sand, silt and occasional wood, concrete and other materials. ■ Tideflat Deposits (Qtf) - silt with sandy layers, organic sediment and shells, generally very loose to medium dense (or very soft to stiff) and gray to black in color. ■ Vashon Recessional Outwash (Qvr) - stratified sand and gravel with varying silt content and occasional cobbles and boulders, generally loose to dense and tan to brown in color. ■ Vashon Advance Outwash (Qva) - stratified sand with gravel layers, and localized zones of silt, generally dense to very dense and brown to gray in color. ■ Pre-Fraser Sediments (Qpf) - undifferentiated mixed fine- and coarse-grained deposits, which have been glacially consolidated and are generally very dense (or hard) and variable in color. Subsurface Explorations We explored site subsurface conditions by advancing one boring to a depth of about 81½ feet bgs at the approximate location shown on Figure 2. We also attempted to advance three shallow hand tool explorations along the mudline beneath the existing pier, using a DCP. The following section provides summary descriptions of the materials encountered in our soil boring. We performed these explorations at low tide on May 18, 2011. In the area of the existing pier, the water was roughly chest deep, and our field staff were not able to advance the DCP more than 1 to 2 feet bgs. Therefore, we have not included DCP exploration results in this report. A description of our field exploration program, including a summary boring log is presented in Appendix A.

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Subsurface Conditions

General Based on our interpretation of the physical and engineering properties of the site soils, we characterize the materials encountered in our exploration into four general units: 1) fill, 2) tideflat deposits, 3) recessional outwash and 4) glacially consolidated deposits. A summary description of each of the soil units is provided below.

FILL UNIT Beneath the pavement surfacing and base course layer, we observed fill to a depth of about 19 feet in our exploration (Elevation +17 to -2 feet MLLW). The fill unit typically comprises loose to medium dense sand with silt and gravel. This unit also contains occasional organic material, brick fragments and other debris and occasional gravel with silt layers. Based on our experience at nearby sites, this unit may also contain riprap and concrete rubble in some areas. We interpret this unit to be consistent with the artificial fill geologic unit described above.

TIDEFLAT DEPOSITS UNIT Underlying the fill, the tideflat deposits unit generally comprises loose to medium dense silty sand with sand layers containing variable silt content and shell fragments. The tideflat deposits unit begins at about 19 feet bgs and extends to about 33 feet bgs (Elevation -2 and -16 feet MLLW) at the boring location. We interpret this unit to be consistent with the Tideflat deposits geologic unit described above.

RECESSIONAL OUTWASH UNIT Underlying the tideflat deposits, our exploration encountered the recessional outwash unit which comprises medium dense silty sand. At our exploration location, this unit is present between about 33 and 38 feet bgs (Elevation -16 and -21 feet MLLW). We interpret this unit to be consistent with the Vashon recessional outwash geologic unit described above.

GLACIALLY CONSOLIDATED DEPOSITS UNIT Underlying the recessional outwash, our exploration encountered the glacially consolidated deposits unit, which typically comprises dense to very dense sand with varying silt and gravel content and occasional very dense silty sand layers. At our exploration location, this unit is present from 38 feet bgs to the full depth explored (Elevation -21 and -64½ feet MLLW). We interpret this unit to be consistent with the Vashon advance outwash and/or pre-Fraser sediments geologic unit described above.

Groundwater Groundwater was encountered at approximately 11½ feet bgs (Elevation 5½ feet MLLW) in our exploration. Groundwater elevations are expected to vary with season and tidal fluctuations. In our analyses we assumed groundwater and sea level to be at Elevation 10 feet MLLW.

Discussion Our understanding of subsurface conditions is based on a drilled exploration in the vicinity of the upland apparatus bay and very shallow hand-tool explorations under the existing pier. Our agreed scope did not include advancing deep explorations in the vicinity of the proposed dock and float improvements because of budget constraints. Our understanding of offshore subsurface

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conditions is based on extrapolation of our on-shore exploration information and our experience. For our analyses, we have assumed that the loose to medium dense tideflats deposits are between 20 and 30 feet thick in the area of the offshore improvements. It is possible that these deposits could be thicker or thinner than assumed, which could require modifying pile embedment during construction to achieve the expected performance of the pile foundations.

SEISMIC DESIGN CONSIDERATIONS

General We understand that seismic design for the proposed fire station improvements will be accomplished using both ASCE 41 and ASCE 7/IBC methods. This will involve assessing three design earthquake events. ASCE 41 design considers two separate earthquake design levels (BSE-1 and BSE-2), and ASCE 7/IBC code uses a different design level (2/3 of the maximum considered earthquake [MCE] Event). The BSE-1 event is defined as an earthquake with a 10 percent probability of exceedance in 50 years (475-year return period) and the BSE-2 event is defined as an earthquake with a 2 percent probability of exceedance in 50 years (2,475-year return period). The MCE event is also defined as an earthquake with a 2 percent probability of exceedance in 50 years (2,475-year return period); however, the ASCE 7/IBC approach uses only 2/3 of the MCE spectra for design.

Seismic Design Parameters

ASCE 41 and ASCE 7/IBC Seismic Design Criteria Seismic design parameters for ASCE 41 and ASCE 7/IBC design are provided in Table 1.

TABLE 1. SEISMIC DESIGN PARAMETERS

ASCE 41 ASCE 7/IBC Seismic Parameter BSE-2 Event BSE-1 Event 2/3 MCE Event (2/3 (2,475 yr) (475 yr) of the 2,475 yr) Site Class E Mapped Spectral Response Acceleration at Short 1.23 g 0.67 g 1.23 g Period (SS) Mapped Spectral Response Acceleration at 1 Second 0.43 g 0.22 g 0.43 g Period (S1) Design Peak Ground Acceleration (PGA) 0.44 g 0.36 g 0.29 g Design Spectral Acceleration at 0.2 second period 1.10 g 0.91 g 0.74 g Design Spectral Acceleration at 1.0 second period 1.02 g 0.69 g 0.68 g

Liquefaction

General Liquefaction refers to the condition by which vibration or shaking of the ground, usually from earthquake forces, results in the development of excess pore pressures in saturated soils, with

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subsequent loss of strength in the deposit of soil so affected. In general, soils that are susceptible to liquefaction include very loose to medium dense clean to silty sands and some silts that are below the water table. Liquefaction effects on foundations can include a temporary loss of bearing capacity, settlement of the ground surface and downdrag loads on pile and shaft foundations. Liquefaction-induced soil strength loss can also result in slope instability and lateral spreading as discussed below.

Liquefaction Analysis We evaluated the liquefaction potential of the site soil using simplified methods (Seed et. al, 2003 and Idriss and Boulanger, 2008), which are based on comparing the cyclic resistance ratio (CRR) of a soil layer (the cyclic shear stress required to cause liquefaction) to the cyclic stress ratio (CSR) induced by an earthquake. The factor of safety (FS) against liquefaction is determined by dividing the CRR by the CSR. For this project we evaluated liquefaction hazards, including settlement and related effects, when the FS against liquefaction was calculated as less than 1.2.

Our analyses indicate that there is potential for liquefaction in the saturated portion of the fill unit and the upper, loose zone of the tideflats deposits unit, during all of the design earthquakes. At our exploration location, the potentially liquefiable soil zone extends from about Elevation +10 feet MLLW to Elevation -10 feet MLLW.

Liquefaction-Induced Settlement We estimate that liquefaction-induced settlement could total between 3 and 6 inches at the ground surface as a result of the BSE-2 event, with differential settlements on the order of 2 to 3 inches per 100 feet. As a result of the BSE-1 and 2/3*MCE events, we estimate that liquefaction-induced settlement could total between 2 and 4 inches at the ground surface, with differential settlements on the order of 1 to 2 inches per 100 feet. However, because liquefaction may occur in isolated and discontinuous zones, differential settlements could approach total settlements.

Liquefied Soil Strength Parameters Based on the results of our liquefaction analysis, and information presented in Soil Liquefaction During Earthquakes, by I.M. Idriss and R.W. Boulanger, 2008, we modeled the potentially liquefiable soil zone as a cohesionless soil with a residual friction angle of 6 degrees. We consider this friction angle to be representative of the residual soil strength for all design earthquake events.

Lateral Spreading Lateral spreading involves lateral displacements of large volumes of soil impacted by liquefaction. Lateral spreading can occur on near-level ground as blocks of near-surface soils are displaced relative to adjacent blocks. Lateral spreading also occurs as blocks of surface soils are displaced toward a nearby slope or free-face by movement of the underlying liquefied soil.

Based on the results of our liquefaction analysis and our experience, it is our opinion that there is significant potential for seismic slope deformation at the project site during the design seismic events. This seismic slope deformation could induce significant lateral loading on the existing and

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new pile foundations and could result in excessive differential settlement or horizontal displacement of the shallow-foundation-supported apparatus bay.

SEISMIC SLOPE DEFORMATION MITIGATION ASSESSMENT

General In our opinion, the most effective way to limit seismic slope deformation and the related lateral loads on structures is through the use of ground improvement. Based on design team discussions, the goal of the ground improvement program for this project was to reduce the potential for large non-liquefied blocks of fill material and soil to move laterally into the pile-supported structure, because this type of failure was deemed to pose the most risk to the structure. Therefore, we focused our assessment of ground improvement on the soils directly landside of the structure. The design team recognizes that the ground improvement program analyzed and recommended herein will not reduce the potential for shallow seismic instability of the slopes beneath the structure, and that seismic instability of these soils these soils could still induce lateral loads on the pile foundations.

There are several ground improvement techniques that could potentially be used at this site. Based on design team discussions, compaction grouting ground improvement was selected to be the most feasible form of ground improvement to reduce the risk of significant seismic slope deformation.

Compaction Grout Columns Compaction grouting is a displacement-based ground improvement that is constructed by driving a small diameter pipe (4 inches or less) to the targeted treatment depth, and then injecting a low slump grout (soil-cement mixture) under high pressure as the pipe is withdrawn. Compaction grout columns typically have a diameter between 2 and 4 feet. The pressurized grout forces the in-situ soil outward, providing densification and reducing the potential for liquefaction. The grout columns reduce lateral slope deformation potential because the grout shear strength is significantly higher than the surrounding soil.

Compaction grouting can accommodate soil with potential obstructions and can be completed at a batter to target specific areas. Compaction grouting construction does not generate significant amounts of excess spoils. Use of low slump grout reduces the potential for grout returning to the surface or the bay.

The following sections present our methodology and analyses for design of compaction grouting.

Slope Stability and Newmark Analyses We completed slope stability and Newmark (horizontal ground deformation) analyses to identify potential critical failure surfaces along the waterway slope and to estimate permanent slope deformation under seismic conditions. We also used these methods to provide estimates of the effects of different ground improvement configurations for the design earthquakes.

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We completed our slope stability analyses using the computer program SLOPE/W (GEO-SLOPE International, Ltd., 2007). SLOPE/W evaluates the stability of numerous trial failure surfaces using vertical slice limit-equilibrium methods. This method compares the ratio of forces driving slope movement with forces resisting slope movement for each trial failure surface, and presents the result as the FS. The program then sorts the trial failure surfaces and identifies the surface with the lowest FS, or the “critical” failure surface.

We completed Newmark analyses using the computer program developed by Jibson and Jibson of United States Geological Survey (USGS) (Open File Report 03-005) using the rigorous rigid block method. Using this software, we created a catalog of 157 applicable earthquake records, based on the moment magnitude and PGA ranges for the design earthquakes. These records were then scaled to match the PGA (Table 1) for the design seismic events. From this information, the software calculates estimated lateral displacement of the failure mass for each earthquake record and presents the average lateral displacement for all selected records. The Newmark approach is a very simplified method of analysis and does not include the effects of initial shear stresses. Also, soil-structure interaction is not considered by Newmark analyses.

Slope Stability Analysis Methodology The evaluation of slope stability, associated ground deformation and potential ground improvement alternatives is an iterative process. In general, our analyses included the following procedures:

1. Complete static slope stability analyses to identify critical failure surfaces and obtain an associated FS, assuming no ground improvement and reduced soil shear strengths associated with liquefaction during the design seismic events. 2. Determine the yield acceleration value for critical failure surfaces with calculated FS greater than 1.0 by varying the pseudo-static seismic coefficient to account for earthquake ground motions. The yield acceleration is defined as the minimum horizontal ground surface acceleration that will cause a specific failure surface to start moving (i.e., FS = 1.0). 3. Complete Newmark analyses to estimate the potential magnitude of lateral slope deformation without ground improvement. 4. Complete iterative static slope stability analyses using reduced soil shear strengths associated with liquefaction and different ground improvement configurations to identify the most effective location and required level of soil improvement, with respect to slope stability. 5. Based on our experience, the required soil strength and site access considerations, qualitatively evaluate the feasibility of different ground improvement layouts to establish the preferred alternative. 6. Complete static slope stability analyses with the selected ground improvement layout, considering liquefied soil conditions and including the improved soil strength parameters in the improved zone. 7. Complete Newmark analyses to estimate the potential magnitude of slope deformation with the selected ground improvement layout.

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Slope Stability Analysis Results

Existing Conditions We completed static slope stability analyses using static soil strengths and reduced, liquefied soil shear strengths to identify a critical failure surface and the existing FS for static and liquefied conditions. The soil shear strengths used in our static and liquefied analyses and the results of our analyses are shown in Figures 3 and 4. The results of our analyses are also summarized in Table 2.

TABLE 2. SLOPE STABILITY ANALYSIS RESULTS – EXISTING CONDITIONS

Analyzed Condition Calculated Factor of Safety Static 2.42 Liquefied 0.57

We calculate a static FS of 0.57 considering liquefied soil parameters. This indicates that, if liquefaction were to occur, a flow-type failure would be likely, and no horizontal ground acceleration would be required to initiate the movement. These types of failures can result in lateral displacements on the order of several feet or more.

Improved Ground Condition We performed iterative slope stability and Newmark analyses to evaluate the compaction grout strength and layout required to achieve the project goal of reducing the potential for large non- liquefied blocks of fill material and soil to move laterally into the pile-supported structure. Based on the results of our iterative analyses, we recommend a compaction grout replacement ratio of approximately 5 percent, with a minimum grout unconfined compressive strength of 1,000 pounds per square inch (psi). Our recommended compaction grouting ground improvement layout is provided on Figure 5.

This layout and replacement ratio increases the total soil shear strength by increasing the density of the soil between the columns and by adding a cohesive strength component to the soil mass. In our analyses, we modeled the shear strength of the improved soil zone using a weighted average of the grout column cohesion and the soil friction angle. In this calculation, we conservatively assumed that the friction angle of the soil between the grout columns was not increased by densification.

To assess the performance of the recommended ground improvement layout, we repeated the static and liquefied analyses described above, this time including the increased shear strength in the improved zone. The soil shear strengths used in our static and liquefied analyses and the results of our analyses are shown in Figures 6 and 7. The results of our analyses are also summarized in Table 3. We calculate a significant increase in both the static and liquefied factors of safety with the recommended compaction grouting ground improvement in place.

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TABLE 3. SLOPE STABILITY ANALYSIS RESULTS – IMPROVED CONDITIONS

Analyzed Condition Calculated Factor of Safety Static 3.65 Liquefied 3.02

Using the slope stability model for the liquefied condition and applying a horizontal ground acceleration coefficient, we calculated a yield acceleration of 0.19g. We used the calculated yield acceleration to estimate horizontal slope deformation for each of the design earthquake levels using the Newmark analysis method. Estimated median lateral deformations are summarized in Table 4.

TABLE 4. ESTIMATED LATERAL SLOPE DISPLACEMENT – IMPROVED CONDITIONS

Design Earthquake Event Median Lateral Displacement (in.) BSE-2 Event (2,475 yr) 1.6 BSE-1 Event (475 yr) 0.6 2/3 MCE Event (2/3 of the 2,475 yr) 0.2

We also completed additional liquefaction analyses assuming improved ground conditions for the design seismic events. The results of our analyses indicate less than 1 inch of liquefaction-related settlement in the improved ground area, during all design seismic events.

CONCLUSIONS AND RECOMMENDATIONS

General Based on the results of our subsurface explorations and analyses, it is our opinion that the proposed improvements are generally feasible from a geotechnical standpoint. Based on our analyses, it is our opinion that significant liquefaction-related ground surface settlement and seismic slope deformation could occur as a result of the design seismic events. We recommend the compaction grouting ground improvement layout shown on Figure 5 to reduce the risk of damage to the structure during the design seismic events. The following sections provide our conclusions and recommendations based on our analyses.

Site Development and Earthwork

General We anticipate that upland site development work will include removal of existing asphalt concrete, clearing and grubbing, excavating to proposed grades below foundations and backfill placement and compaction. Depending on final plans, earthwork may also include installing ground improvement. We expect that the majority of site grading and earthwork can be accomplished with conventional earthmoving equipment.

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Subgrade Preparation Subgrades and foundation bearing surfaces should be thoroughly compacted to a uniformly firm and unyielding condition on completion of stripping and before placing structural fill or foundation elements. We recommend subgrade soil be proof-rolled to identify areas of yielding prior to the placement of fill or other structural elements. Proof-rolling should be accomplished with a heavy piece of wheeled construction equipment such as a loaded dump truck or front-end loader; alternatively, the exposed subgrade soil can be probed by an experienced person using a steel rod. If soft or otherwise unsuitable areas are revealed during proof-rolling or probing that cannot be compacted to a stable and uniformly firm condition, we recommend that: 1) the subgrade soils be scarified (e.g., with a ripper or farmer’s disc), aerated and recompacted; or 2) the unsuitable soils be removed and replaced with compacted structural fill, as needed.

Based on our experience and the materials encountered in our explorations, portions of the on-site soils might not be readily compactable to an unyielding condition because of excessive moisture content. Accordingly, we recommend that project plans include a contingency for partial overexcavation of unsuitable existing site soils and replacement with compacted structural fill below shallow foundations. Overexcavations should extend laterally beyond the foundation perimeter a distance equal to one-half the depth of overexcavation. We estimate that overexcavation on the order of 2 feet below shallow foundations may be needed, particularly if construction is performed during wet weather.

We recommend that subgrade preparation, foundation excavations and structural fill placement be observed by a representative from our firm to check that the procedures comply with the intent of our recommendations and the project plans and specifications.

Wet Weather Construction Portions of the soil encountered in the exploration contain a significant percentage of fines. This material may be very sensitive to small changes in moisture content. Site soil may be difficult, if not impossible, to work and compact when wet. Soil with high fines content is very susceptible to disturbance from construction traffic when wet or if earthwork is performed during wet weather. A contingency should be included in the project budget and schedule if wet weather construction is anticipated

Fill Materials

GENERAL Material used for fill should be free of debris, organic contaminants and rock fragments larger than 6 inches. The workability of material for use as fill will depend on the gradation and moisture content of the soil. As the amount of fines (material passing the U.S. Standard No. 200 sieve) increases, soil becomes increasingly sensitive to small changes in moisture content, and adequate compaction becomes difficult or impossible to achieve. During dry weather, we recommend that fill material consist of “Select Borrow” as described in Section 9-03.14(2) of the Washington State Department of Transportation (WSDOT) Standard Specifications. If construction is performed during wet weather, we recommend using fill consisting of select granular fill as described below. If prolonged dry weather prevails during the earthwork phase of construction, a somewhat higher fines content may be acceptable.

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SELECT GRANULAR FILL We recommend that fill placed beneath structural elements consist of material of the same quality as “Gravel Borrow” as described in Section 9-03.14(1) of the WSDOT Standard Specifications, with the exception that less than 5 percent passes the No. 200 sieve. Alternatively, “Gravel Backfill for Walls” as described in Section 9-03.12(2) of the WSDOT Standard Specifications may be considered.

USE OF ON-SITE SOIL AS FILL Based on our subsurface explorations, soil from the existing fill unit may be considered for use as structural fill provided it meets the prescribed fill material recommendation and can be placed and compacted as recommended. However, this soil contains occasional organic material, brick fragments and other debris that need to be removed prior to using the material as structural fill. Although not specifically addressed in this report, environmental considerations could also limit the reuse of on-site fill materials.

Fill Placement and Compaction Structural fill should be compacted at a moisture content near optimum. The optimum moisture content varies with the soil gradation and should be evaluated during construction. Subgrades to receive structural fill should be firm and unyielding. Fill material should be placed in uniform, horizontal lifts and uniformly densified with vibratory compaction equipment. The maximum lift thickness will vary depending on the material and compaction equipment used, but generally should not exceed 10 to 12 inches in loose thickness. We recommend structural fill be compacted to at least 95 percent of the maximum dry density (MDD) determined by ASTM International (ASTM) Test Method D 1557 (modified Proctor).

Shallow Foundation Support of Apparatus Bay

Spread Footings The proposed upland apparatus bay may be founded on continuous wall or isolated column footings established on bearing surfaces that are prepared in accordance with the “Subgrade Preparation” section. We recommend a minimum width of 18 inches for continuous wall footings and 2 feet for isolated column footings. We recommend footing elements be embedded at least 18 inches below the lowest adjacent external grade.

Footings founded as described on unyielding medium dense or denser soil or structural fill extending to such soils may be designed using an allowable soil bearing pressure of 2,000 pounds per square foot (psf). This value applies to long-term dead plus live loads and is exclusive the weight of the footing and any overlying backfill. This allowable soil bearing pressure may be increased by one-third when considering total loads, including transient loads such as those induced by wind and seismic forces. We estimate settlement of spread footings designed and constructed in accordance with these recommendations should be in the range of 1 inch or less.

Slabs-on-Grade A modulus of subgrade reaction should be used for structural design of slabs-on-grade. Once final loading information is available, the structural engineer should use the modulus of subgrade reaction to size the slab. We recommend that any interior slabs-on-grade be underlain by a

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minimum 6-inch-thick capillary break layer to reduce the potential for moisture migration into the slab. The capillary break material should consist of a well-graded sand and gravel or crushed rock with a maximum particle size of 3/4 inch and less than 3 percent fines. The capillary break material should be placed in one lift, directly on top of subgrades prepared as described in the “Subgrade Preparation” section. If dry slabs are required (for example, where adhesives are used to anchor carpet or tile to the slab), a waterproof liner should be placed as a vapor retarder below the slab.

We estimate that a modulus of subgrade reaction of about 150 pci is appropriate for evaluating a slab-on-grade foundation for this site, provided the slab bears on prepared subgrades or compacted structural fill as described above. This modulus value is for a 1-foot by 1-foot square plate. The actual modulus for a foundation element varies based on the footing size according to the following equation:

ks = ks1[(B+1)/2B]2 where ks is the actual subgrade modulus, ks1 is the modulus for a 1-foot by 1-foot plate, and B is the width or lateral dimension of the footing.

For slabs-on-grade designed and constructed as recommended, we estimate settlements less than 1 inch. We estimate that differential settlement of the floor slabs will be ½ inch or less over a span of 50 feet.

Lateral Load Resistance for Shallow Foundations Lateral loads on shallow foundation elements may be resisted by passive resistance on the sides of footings and other below-grade structural elements and by friction on the base of footings. Passive resistance may be estimated using an equivalent fluid density of 250 pounds per cubic foot (pcf), assuming that the footings and below-grade elements are backfilled with structural fill placed and compacted as recommended. The top foot of soil should be neglected when calculating passive resistance unless the area is covered by pavement or a slab-on-grade. Frictional resistance may be estimated using 0.35 for the coefficient of base friction between soil and concrete.

The above values are applicable where foundation elements are above the groundwater table and include a FS of about 1.5. The passive earth pressure and friction components may be combined provided that the passive pressure component does not exceed two-thirds of the total.

Pile Design Considerations

General Our agreed scope did not include offshore explorations in the areas where piles will be installed. Therefore, our understanding of offshore subsurface conditions is limited, and conditions at the actual pile locations could be different than assumed. Different soil conditions could significantly affect the performance of the pile foundations. We recommend that GeoEngineers be retained to observe pile installation, and that contingencies be included to modify the required pile embedment or capacity based on observations. The pile capacities presented below are

July 3, 2012 | Page 13 File No. 0570-113-01 MARITIME SECURITY OPERATIONS CENTER Tacoma, Washington

preliminary, and subject to confirmation or revision at the time of construction, based on observed pile resistance and penetration rates.

Axial Pile Capacity We developed estimates of axial pile capacities for 12.75- and 18-inch diameter, open-tip steel pipe piles. We understand that piles may be driven to near final tip elevation using vibratory methods. Therefore, we anticipate that soil plugging within the pipe pile may not occur. Our pile capacity estimates have limited end-bearing resistance.

Our estimates for allowable axial pile capacity versus pile embedment are provided on Figures 8 and 9. The axial pile capacities provided on Figures 8 and 9 include FS of 2 for side friction resistance and 3 for end-bearing resistance.

Settlement Pile settlement under design loads is not expected to exceed about 1 inch. Differential settlement between comparably loaded piles is not expected to exceed about ½ inch.

Lateral Pile Performance We performed LPILE analyses to estimate performance of piles for the pier, gangway and floats under design lateral loading. Table 5 presents the analyzed loading cases, based on information provided by Reid Middleton, Inc. Figures 10 through 24 present the results of our analyses. Depths indicated on the figures are measured below top of pile. These analyses do not include the effects of liquefaction or seismic slope deformation-related loads on piles. We recommend further analyses be considered to assess seismic performance, depending on the seismic performance goals of the project.

Our analyses are representative of the soil-structure interaction only, and do not include assessment of pile structural performance. The structural engineer should assess structural performance of the piles and check whether the bending moments and shear forces are within the structural capacity of the piles.

TABLE 5. ANALYZED LATERAL PILE LOADING CASES

Lateral Load Pile Location Pile Size Load Case Figures (kips) BSE-1 17 Pier 18” x 0.5” wall 10, 11, 12 BSE-2 24 Gangway 12.75” x 0.5” wall - 5 13, 14, 15 P2 25.22 Float Row 1 30” x 0.5” wall 16, 17, 18 P4 13.65 P1 17.60 Float Row 2 30” x 0.5” wall 19, 20, 21 P4 13.65 P3 17.84 Float Row 3 30” x 0.5” wall 22, 23, 24 P4 13.65

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Pile Installation Considerations During our site visits and explorations, we observed riprap slope protection present along the slope beneath the existing pier, extending to about Elevation -3 to -5 feet MLLW. This material could impede pile driving and might need to be removed at planned pile locations, prior to pile driving activities. Below the riprap slope protection, we anticipate that conventional vibratory driving methods can be used to advance the piles to the elevation of the glacially consolidated soils. Impact driving may be required to penetrate more than a few feet into these very dense soils. We recommend that the contractor perform a wave equation analysis of pile driving (WEAP) to assess pile driveability for each of the hammer/pile combinations planned prior to acceptance of the proposed hammer(s).

LIMITATIONS

We have prepared this report for use by Reid Middleton, Inc. and the City of Tacoma for the Maritime Security Operations Center project in Tacoma, Washington.

Within the limitations of scope, schedule and budget, our services have been executed in accordance with generally accepted practices in the field of geotechnical engineering in this area at the time this report was prepared. No warranty or other conditions express or implied should be understood.

Please refer to Appendix B “Report Limitations and Guidelines for Use” for additional information pertaining to use of this report.

July 3, 2012 | Page 15 File No. 0570-113-01 N 49Th St

N Ruby St N Waterview St

N Orchard St N 48Th St

N 47Th St N 47ThBaltimoreBaltimore St ParkPark N 46Th St N 45Th St Ruston Way N 44Th St

N Mullen St N Gove St n N 43Rd St N Verde St

N Huson St

N Ferdinand St N 42Nd St N 41St St N 41St St

N MasonAve N 39Th StJaneJane ClarkClark PlaygroundPlayground n Sherman Elementary School Marine Park N 38Th St Site N 37Th St N 38Th St !

N Proctor St

N Madison St N 36Th St

N Villard St N 35Th St

N AdamsN St

N Warner St St Warner N N Alder St

N Verde St N 34Th St

N Cheyenne St N Monroe St N Baltimore St N Ferdinand St N 34Th St N 33Rd St N 33Rd St Map Map Revised: 03July 2012 syi

N Puget SoundAve

N Villard St N 32Nd St N 32Nd St Hamilton Park

N Huson St N Orchard St N 31St St PugetPuget ParkPark N 31St St Pierce County AlderN St N 30Th St Comencment Park

N Verde St N 29Th St N 28Th St Mason Middlen School Old Town Park N Cedar St Schuster Pky

N MasonAve n N 27Th St Hoyt Elementary School N 27Th St N Park Dr N 26Th St Washington Elementaryn School Mccarver St

N Junett St W N W N 26Th St

N Verde St

n N Starr St Downing Elementary School N 25Th St N C St N 24Th St NE Garfield Park N D St

N Mullen St N 11Th St

N Lawrence St n N 22Nd St N 22Nd St N Carr St n Wright Seminary N AdamsN St nAquinas AcademyGwen E Johnson School of Learning N 21St St Lowell Elementary School Annie Wrightn School N E St n

N TylerN St N 20Th St

N 19Th St N Fife St

N Ferdinand St

N Monroe St N Cheyenne St n N Stevens St

N Proctor St Central Luthern Christian School N 18Th St N Warner St N 19Th St

N AndersonN St

N Madison St N Oakes St n N Villard St N 17Th St Saint Patricks School N G St N Verde St N 16Th St N 9Th St N Yakima Ave N J St N I St N 15Th St N L St N K St n N 15Th St N Steele St

N Fife St University of Puget Sound N Prospect St N 14Th St

N Pine St n n W a s h i n g t o n µ ¨¦§405 ¨¦§90 2,000 0 2,000 5 ¨¦§ Feet 84 ¨¦§ O r e g o n Notes: 1. The locations of all features shown are approximate. Vicinity Map 2. This drawing is for information purposes. It is intended to assist in showing features discussed in an attached document. GeoEngineers, Inc. can not guarantee the accuracy and content of electronic files. The master file is stored by GeoEngineers, Inc. and will serve as the official record of Maritime Security Operations Center this communication. Tacoma, Washington 3. It is unlawful to copy or reproduce all or any part thereof, whether for personal use or resale, without permission. Data Sources: ESRI Data & Maps, Street Maps 2005 Figure 1 Transverse Mercator, State Plane South, North American Datum 1983 North arrow oriented to grid north Office:TACO Path: P:\0\0570113\GIS\057011301_T500_F1_VicinityMap.mxd

0570-113-01

SLOPE/W Analysis – Existing Conditions - Static Maritime Security Operations Center Tacoma, Washington

Figure 3 0570-113-01

SLOPE/W Analysis – Existing Conditions - Liquefied Maritime Security Operations Center Tacoma, Washington

Figure 4

0570-113-01

SLOPE/W Analysis – Improved Ground Conditions - Static Maritime Security Operations Center Tacoma, Washington

Figure 6 0570-113-01

SLOPE/W Analysis – Improved Ground Conditions - Liquefied Maritime Security Operations Center Tacoma, Washington

Figure 7 Allowable Capacity (kips)

0 50 100 150 200 250 0

40 Embedment (ft)

End Bearing Side Friction Total Downward

Allowable Axial Pile Capacity - 18 inch Pipe Piles Maritime Security Operations Center Tacoma, Washington

Figure 8 0570-113-01 Allowable Capacity (kips)

0 50 100 150 200 250 0

40 Embedment (ft)

End Bearing Side Friction Total Downward

Allowable Axial Pile Capacity - 12.75 inch Pipe Piles Maritime Security Operations Center Tacoma, Washington

Figure 9 0570-113-01 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Maritime Security Operations Maritime Security Center aea ieAayi Pier Lateral Pile - Analysis Tacoma, Washington Figure 10 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Maritime Security Operations Maritime Security Center aea ieAayi Pier Lateral Pile - Analysis Tacoma, Washington Figure 11 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Maritime Security Operations Maritime Security Center aea ieAayi Pier Lateral Pile - Analysis Tacoma, Washington Figure 12 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: aea ieAayi Gangway Lateral Pile - Analysis Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 13 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: aea ieAayi Gangway Lateral Pile - Analysis Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 14 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: aea ieAayi Gangway Lateral Pile - Analysis Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 15 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 1 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 16 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 1 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 17 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 1 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 18 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 2 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 19 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 2 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 20 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 2 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 21 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 3 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 22 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 3 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 23 0570-113-01 top elevation assumed to top elevation be +17 MLLW. feet Depth measuredin feet below top of pile. Pile Note: Lateral Pile Analysis – Float Row 3 Row Float Lateral Pile Analysis– Maritime Security Operations Maritime Security Center Tacoma, Washington Figure 24

APPENDIX A Subsurface Explorations and Laboratory Testing

MARITIME SECURITY OPERATIONS CENTER Tacoma, Washington

APPENDIX A SUBSURFACE EXPLORATIONS AND LABORATORY TESTING

General We explored site subsurface conditions by advancing one boring to a depth of about 81½ feet below ground surface (bgs) on May 12, 2011, at the approximate location shown on Figure 2. We also advanced three shallow hand tool explorations along the mudline beneath the existing pier, using a dynamic cone penetrometer on May 18, 2011. Our representative located the explorations in the field using measurements from existing site features. Elevation information provided on the boring log is based on the site plan provided by Reid Middleton. Because the boring was located by field measurement the location and elevation should be considered approximate. A key to the symbols used on the boring log is included as Figure A-1. A summary boring log is included as Figure A-2.

Soil Boring The soil boring was advanced by Holocene Drilling using a truck-mounted drill rig subcontracted by GeoEngineers. Hollow-stem auger and mud rotary drilling methods were used to advance the boring.

Disturbed soil samples were obtained from the boring using a 1.375-inch inside-diameter split- spoon SPT sampler driven into the soil using a 140-pound hammer free-falling a distance of 30 inches. The number of blows (N) required to drive the sampler the last 12 inches or until refusal was met (N>50) is recorded on the logs as the blow count. In some cases, additional sample recovery attempts were made using a 2.4-inch-inside-diameter split spoon sampler.

Our representative continuously monitored the boring, maintained a log of the subsurface conditions and observed sample attempts, generally at 2.5- to 5-foot-depth intervals. The soils encountered were visually classified in general accordance with ASTM International (ASTM) D 2488 (visual-manual procedure) and the classification chart shown in Figure A-1.

The boring was backfilled and concrete-patched by Holocene Drilling.

DCP Soundings Dynamic Cone Penetrometer (DCP) tests were conducted at three locations beneath the existing pier. The DCP test involves using a 15 pound steel slide hammer falling 20 inches to strike an anvil mounted on the test rod. The impact drives a 1.5-inch-diameter cone into the soil. The blows required to drive the embedded cone a depth of 1-3/4 inches are correlated to N values that typically are derived from the Standard Penetration Test (SPT). We performed these explorations at low tide on May 18, 2011. In the area of the existing pier, the water was roughly chest deep, and our field staff were not able to advance the DCP more than 1 to 2 feet bgs. Therefore, we have not included DCP exploration results in this report.

July 3, 2012 | Page A-1 File No. 0570-113-01 MARITIME SECURITY OPERATIONS CENTER Tacoma, Washington

Laboratory Testing

General Soil samples obtained from the boring were returned to our laboratory for further examination and review. Representative soil samples were selected for laboratory tests to evaluate their pertinent geotechnical engineering characteristics and to confirm or modify our field classifications. The following paragraphs provide a description of the tests performed.

Moisture Content The moisture content of selected samples was determined in general accordance with ASTM Test Method D 2216. The test results are used to aid in soil classification and correlation with other pertinent engineering soil properties. The results of these tests are presented on the exploration log at the respective sample depths.

Percent Passing U.S. No. 200 Sieve (%F) Selected samples were “washed” through the U.S. No. 200 mesh sieve to estimate the relative percentages of coarse- and fine-grained particles in the soil. The percent passing value represents the percentage by weight of the sample finer than the U.S. No. 200 sieve. The tests were conducted in general accordance with ASTM D 1140 and the results are shown on the boring log at the respective sample depths.

Grain-size Analyses Grain-size analyses were performed on selected samples in general accordance with ASTM Test Method D 422. This test method covers the quantitative determination of the distribution of soil particles larger than 75 micrometers (μm). The test results were used to verify field soil classifications and assess infiltration feasibility. Figure A-3 presents the results of our grain-size analyses.

Page A-2 | July 3, 2012 | GeoEngineers, Inc. File No. 0570-113-01 SOIL CLASSIFICATION CHART ADDITIONAL MATERIAL SYMBOLS

SYMBOLS TYPICAL SYMBOLS TYPICAL MAJOR DIVISIONS GRAPH LETTER DESCRIPTIONS GRAPH LETTER DESCRIPTIONS

WELL-GRADED GRAVELS, GRAVEL - CLEAN GW SAND MIXTURES CC Cement Concrete GRAVEL GRAVELS AND GRAVELLY (LITTLE OR NO FINES) POORLY-GRADED GRAVELS, GP GRAVEL - SAND MIXTURES SOILS AC Asphalt Concrete

COARSE GRAVELS WITH SILTY GRAVELS, GRAVEL - SAND - GRAINED MORE THAN 50% GM SILT MIXTURES Crushed Rock/ OF COARSE FINES CR SOILS FRACTION Quarry Spalls RETAINED ON NO. (APPRECIABLE AMOUNT 4 SIEVE CLAYEY GRAVELS, GRAVEL - SAND - OF FINES) GC CLAY MIXTURES Topsoil/ TS Forest Duff/Sod WELL-GRADED SANDS, GRAVELLY CLEAN SANDS SW SANDS MORE THAN 50% SAND RETAINED ON NO. AND (LITTLE OR NO FINES) 200 SIEVE POORLY-GRADED SANDS, SANDY SP GRAVELLY SAND SOILS Measured groundwater level in exploration, well, or piezometer MORE THAN 50% SANDS WITH SM SILTY SANDS, SAND - SILT OF COARSE MIXTURES Groundwater observed at time of FRACTION FINES PASSING NO. 4 exploration SIEVE (APPRECIABLE AMOUNT SC CLAYEY SANDS, SAND - CLAY OF FINES) MIXTURES Perched water observed at time of exploration INORGANIC SILTS, ROCK FLOUR, ML CLAYEY SILTS WITH SLIGHT PLASTICITY Measured free product in well or piezometer INORGANIC CLAYS OF LOW TO SILTS MEDIUM PLASTICITY, GRAVELLY AND LIQUID LIMIT CL CLAYS, SANDY CLAYS, SILTY CLAYS, FINE LESS THAN 50 LEAN CLAYS Graphic Log Contact GRAINED CLAYS SOILS ORGANIC SILTS AND ORGANIC Distinct contact between soil strata or OL SILTY CLAYS OF LOW PLASTICITY geologic units Approximate location of soil strata MORE THAN 50% INORGANIC SILTS, MICACEOUS OR PASSING NO. 200 MH DIATOMACEOUS SILTY SOILS change within a geologic soil unit SIEVE SILTS LIQUID LIMIT INORGANIC CLAYS OF HIGH Material Description Contact AND GREATER THAN 50 CH PLASTICITY CLAYS Distinct contact between soil strata or ORGANIC CLAYS AND SILTS OF geologic units OH MEDIUM TO HIGH PLASTICITY Approximate location of soil strata

PEAT, HUMUS, SWAMP SOILS WITH change within a geologic soil unit HIGHLY ORGANIC SOILS PT HIGH ORGANIC CONTENTS

NOTE: Multiple symbols are used to indicate borderline or dual soil classifications Laboratory / Field Tests Sampler Symbol Descriptions %F Percent fines AL Atterberg limits 2.4-inch I.D. split barrel CA Chemical analysis CP Laboratory compaction test Standard Penetration Test (SPT) CS Consolidation test DS Direct shear HA Hydrometer analysis Shelby tube MC Moisture content MD Moisture content and dry density Piston OC Organic content PM Permeability or hydraulic conductivity Sonic Core PP Pocket penetrometer SA Sieve analysis Bulk or grab TX Triaxial compression UC Unconfined compression VS Vane shear Blowcount is recorded for driven samplers as the number of blows required to advance sampler 12 inches (or Sheen Classification distance noted). See exploration log for hammer weight and drop. NS No Visible Sheen SS Slight Sheen A "P" indicates sampler pushed using the weight of the MS Moderate Sheen drill rig. HS Heavy Sheen NT Not Tested

NOTE: The reader must refer to the discussion in the report text and the logs of explorations for a proper understanding of subsurface conditions. Descriptions on the logs apply only at the specific exploration locations and at the time the explorations were made; they are not warranted to be representative of subsurface conditions at other locations or times.

KEY TO EXPLORATION LOGS

FIGURE A-1 Start End Total Logged By CAJ Drilling Hollow Stem Auger/Mud 81.5 Driller Holocene Drilled 5/12/2011 5/12/2011 Depth (ft) Checked By MM Method Rotary Hammer Drilling Surface Elevation (ft) 17.0 Truck Mounted Vertical Datum Data 140 lb/30 inch drop Autohammer Equipment

Easting (X) System Groundwater Northing (Y) Datum Depth to Date Measured Water (ft) Elevation (ft) Notes: 5/12/2011 11.6 5.4

FIELD DATA

MATERIAL REMARKS DESCRIPTION Elevation (feet) Depth (feet) Interval Recovered (in) Blows/foot Collected Sample Sample Name Testing Water Level Graphic Log Group Classification Moisture Content, % Dry Density, (pcf) 0 AC 4.5 inches asphalt concrete GP-GM Gray fine to coarse gravel with sand and silt (crushed rock fill) 15 SP-SM Brown fine to coarse sand with silt, gravel, occasional brick fragments and trace organics (loose, moist) (fill)

5 8 9 1 GP-GM Gray fine to coarse gravel with silt and sand (loose, moist) (fill) 10

SP-SM Brown fine to medium sand with silt, gravel and brick fragments (loose, wet) (fill) 10 7 4 2

15 18 20 3 Grades to medium dense 20 %F=6 %F SP-SM Black medium to coarse sand with silt and gravel 0 (medium dense, wet) (fill)

Brick fragments observed near top of SP-SM Dark gray fine to coarse sand with silt, wood tideflat deposits only 20 4 debris and brick fragments (loose, wet) 18 9 (tideflat deposits)

-5

25 18 21 5 Grades to medium dense %F SM Dark gray silty fine to medium sand with 21 %F=16 -10 occasional wood debris and shell fragments (medium dense, wet) (tideflat deposits)

30 16 29 6 Grades to fine to medium sand with silt 25 %F=11 %F

-15

SM Brown silty fine to coarse sand with occasional gravel (medium dense, wet) (recessional outwash) 35 18 25 7 19 %F=16 SA

-20

SP-SM Brown fine to coarse sand with silt and gravel (dense, wet) (glacially consolidated deposits) 40

Note: See Figure A-1 for explanation of symbols.

Log of Boring B-1 Project: Maritime Security Operations Center Project Location: Tacoma, Washington Figure A-2 Tacoma: Date:7/3/12 Path:P:\0\0570113\GINT\057011301.GPJ DBTemplate/LibTemplate:GEOENGINEERS8.GDT/GEI8_GEOTECH_STANDARD Project Number: 0570-113-01 Sheet 1 of 2 FIELD DATA

-25

45 Grades to very dense 18 88 9 11 %F=10 SA

-30

SP-SM Brown fine to coarse sand with silt and gravel (very dense, wet) (glacially consolidated 50 19 55 10 deposits)

-35

55 SP Brown fine to medium sand with trace silt (very 9 50/3" 11 24 %F=3 %F dense, wet) (glacially consolidated deposits)

-40

SP-SM Brown fine to coarse sand with silt and -45 occasional gravel (very dense, wet) (glacially consolidated deposits)

65 14 81 12 13 %F=10 %F

-50

70 Grades to with gravel 8 70 13

-55

75 6 24 14 Grades to medium dense Blow count not representative due to heave

-60

SM Brown silty fine to coarse sand with gravel (very dense, wet) (glacially consolidated deposits) 80 7 71 15

Note: See Figure A-1 for explanation of symbols.

Log of Boring B-1 (continued) Project: Maritime Security Operations Center Project Location: Tacoma, Washington Figure A-2 Tacoma: Date:7/3/12 Path:P:\0\0570113\GINT\057011301.GPJ DBTemplate/LibTemplate:GEOENGINEERS8.GDT/GEI8_GEOTECH_STANDARD Project Number: 0570-113-01 Sheet 2 of 2 0570-113-01 MM:EAW:tt

U.S. STANDARD SIEVE SIZE 3” 1.5” 3/4” 3/8” #4 #10 #20 #40 #60 #100 #200 100

20 PERCENT PASSING BY WEIGHT WEIGHT BY PASSING PERCENT 10

0 1000 100 10 1 0.1 0.01 0.001 Maritime Security Operations Center GRAIN SIZE IN MILLIMETERS Sieve Analysis Results Tacoma, Washington Tacoma,

GRAVEL SAND COBBLES SILT OR CLAY COARSE FINE COARSE MEDIUM FINE

EXPLORATION DEPTH MOISTURE SYMBOL SOIL CLASSIFICATION Figure A-3 NUMBER (ft) (%) B-1 35 19 Silty sand (SM) B-1 45 11 Sand with silt and gravel (SP-SM)

APPENDIX B Report Limitations and Guidelines for Use

MARITIME SECURITY OPERATIONS CENTER Tacoma, Washington

APPENDIX B REPORT LIMITATIONS AND GUIDELINES FOR USE1

This appendix provides information to help you manage your risks with respect to the use of this report.

Geotechnical Services are Performed for Specific Purposes, Persons and Projects This report has been prepared for the exclusive use of Reid Middleton, Inc., the City of Tacoma and their authorized agents. This report is not intended for use by others, and the information contained herein is not applicable to other sites.

GeoEngineers structures our services to meet the specific needs of our clients. For example, a geotechnical or geologic study conducted for a civil engineer or architect may not fulfill the needs of a construction contractor or even another civil engineer or architect that are involved in the same project. Because each geotechnical or geologic study is unique, each geotechnical engineering or geologic report is unique, prepared solely for the specific client and project site. Our report is prepared for the exclusive use of our Client. No other party may rely on the product of our services unless we agree in advance to such reliance in writing. This is to provide our firm with reasonable protection against open-ended liability claims by third parties with whom there would otherwise be no contractual limits to their actions. Within the limitations of scope, schedule and budget, our services have been executed in accordance with our Agreement with the Client and generally accepted geotechnical practices in this area at the time this report was prepared. This report should not be applied for any purpose or project except the one originally contemplated.

A Geotechnical Engineering or Geologic Report is Based on a Unique Set of Project- Specific Factors This report has been prepared for the Maritime Security Operations Center project in Tacoma, Washington. GeoEngineers considered a number of unique, project-specific factors when establishing the scope of services for this project and report. Unless GeoEngineers specifically indicates otherwise, do not rely on this report if it was:

■ not prepared for you, ■ not prepared for your project, ■ not prepared for the specific site explored, or ■ completed before important project changes were made. For example, changes that can affect the applicability of this report include those that affect:

■ the function of the proposed structure; ■ elevation, configuration, location, orientation or weight of the proposed structure;

1 Developed based on material provided by ASFE, Professional Firms Practicing in the Geosciences; www.asfe.org.

July 3, 2012 | Page B-1 File No. 0570-113-01 MARITIME SECURITY OPERATIONS CENTER Tacoma, Washington

■ composition of the design team; or ■ project ownership. If important changes are made after the date of this report, GeoEngineers should be given the opportunity to review our interpretations and recommendations and provide written modifications or confirmation, as appropriate.

Subsurface Conditions Can Change This geotechnical or geologic report is based on conditions that existed at the time the study was performed. The findings and conclusions of this report may be affected by the passage of time, by manmade events such as construction on or adjacent to the site, or by natural events such as floods, earthquakes, slope instability or groundwater fluctuations. Always contact GeoEngineers before applying a report to determine if it remains applicable.

Topsoil For the purposes of this report, we consider topsoil to consist of generally fine-grained soil with an appreciable amount of organic matter based on visual examination, and to be unsuitable for direct support of the proposed improvements. However, the organic content and other mineralogical and gradational characteristics used to evaluate the suitability of soil for use in landscaping and agricultural purposes was not determined, nor considered in our analyses. Therefore, the information and recommendations in this report, and our logs and descriptions should not be used as a basis for estimating the volume of topsoil available for such purposes.

Most Geotechnical and Geologic Findings Are Professional Opinions Our interpretations of subsurface conditions are based on field observations from widely spaced sampling locations at the site. Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. GeoEngineers reviewed field and laboratory data and then applied our professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. Our report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions.

Geotechnical Engineering Report Recommendations Are Not Final Do not over-rely on the preliminary construction recommendations included in this report. These recommendations are not final, because they were developed principally from GeoEngineers’ professional judgment and opinion. GeoEngineers’ recommendations can be finalized only by observing actual subsurface conditions revealed during construction. GeoEngineers cannot assume responsibility or liability for this report's recommendations if we do not perform construction observation.

Sufficient monitoring, testing and consultation by GeoEngineers should be provided during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether or not earthwork activities are completed in accordance with our recommendations. Retaining GeoEngineers for construction

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observation for this project is the most effective method of managing the risks associated with unanticipated conditions.

A Geotechnical Engineering or Geologic Report Could be Subject to Misinterpretation Misinterpretation of this report by other design team members can result in costly problems. You could lower that risk by having GeoEngineers confer with appropriate members of the design team after submitting the report. Also retain GeoEngineers to review pertinent elements of the design team's plans and specifications. Contractors can also misinterpret a geotechnical engineering or geologic report. Reduce that risk by having GeoEngineers participate in pre-bid and preconstruction conferences, and by providing construction observation.

Do Not Redraw the Exploration Logs Geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering or geologic report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk.

Give Contractors a Complete Report and Guidance Some owners and design professionals believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give contractors the complete geotechnical engineering or geologic report, but preface it with a clearly written letter of transmittal. In that letter, advise contractors that the report was not prepared for purposes of bid development and that the report's accuracy is limited; encourage them to confer with GeoEngineers and/or to conduct additional study to obtain the specific types of information they need or prefer. A pre-bid conference can also be valuable. Be sure contractors have sufficient time to perform additional study. Only then might an owner be in a position to give contractors the best information available, while requiring them to at least share the financial responsibilities stemming from unanticipated conditions. Further, a contingency for unanticipated conditions should be included in your project budget and schedule.

Contractors are Responsible for Site Safety on their Own Construction Projects Our geotechnical recommendations are not intended to direct the contractor’s procedures, methods, schedule or management of the work site. The contractor is solely responsible for job site safety and for managing construction operations to minimize risks to on-site personnel and to adjacent properties.

Read These Provisions Closely Some clients, design professionals and contractors may not recognize that the geoscience practices (geotechnical engineering or geology) are far less exact than other engineering and natural science disciplines. This lack of understanding can create unrealistic expectations that could lead to disappointments, claims and disputes. GeoEngineers includes these explanatory “limitations” provisions in our reports to help reduce such risks. Please confer with GeoEngineers

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if you are unclear how these “Report Limitations and Guidelines for Use” apply to your project or site.

Geotechnical, Geologic and Environmental Reports Should not be Interchanged The equipment, techniques and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical or geologic study and vice versa. For that reason, a geotechnical engineering or geologic report does not usually relate any environmental findings, conclusions or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Similarly, environmental reports are not used to address geotechnical or geologic concerns regarding a specific project.

Biological Pollutants GeoEngineers’ Scope of Work specifically excludes the investigation, detection, prevention, or assessment of the presence of Biological Pollutants in or around any structure. Accordingly, this report includes no interpretations, recommendations, findings, or conclusions for the purpose of detecting, preventing, assessing, or abating Biological Pollutants. The term “Biological Pollutants” includes, but is not limited to, molds, fungi, spores, bacteria, and viruses, and/or any of their byproducts.

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