Geotechnical Engineering Report Mcleod Plantation Charleston, South Carolina June 19, 2013 Terracon Project No

Geotechnical Engineering Report McLeod Plantation Charleston, South Carolina June 19, 2013 Terracon Project No. EN135028 Revision 1

Prepared for: Charleston County Park and Recreation Commission And The Jaeger Company Gainesville, Georgia

Prepared by: Terracon Consultants, Inc. North Charleston, South Carolina

TABLE OF CONTENTS Page EXECUTIVE SUMMARY ...... i 1.0 INTRODUCTION ...... 1 2.0 PROJECT INFORMATION ...... 2 2.1 Project Description ...... 2 2.2 Site Location and Description ...... 2 3.0 SUBSURFACE CONDITIONS ...... 3 3.1 Typical Soil Profile ...... 3 3.2 Groundwater ...... 3 4.0 GEOTECHNICAL SEISMIC CONSIDERATIONS ...... 4 4.1 Seismic Evaluation ...... 4 4.2 Liquefaction Potential ...... 5 5.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ...... 6 5.1 Geotechnical Considerations ...... 6 5.2 Earthwork ...... 6 5.2.1 Site Preparation ...... 6 5.2.2 Material Types ...... 7 5.2.3 Compaction Requirements ...... 7 5.3 Shallow Foundation Recommendations ...... 7 5.3.1 Shallow Foundation Design Recommendations...... 8 5.3.2 Shallow Foundation Construction Considerations ...... 8 5.4 Floor Slabs...... 9 5.4.1 Floor Slab Design Recommendations ...... 9 5.4.2 Floor Slab Construction Considerations ...... 9 5.5 Deep Foundations ...... 10 5.5.1 Deep Foundation Axial Capacity ...... 10 5.5.2 Deep Foundation Installation ...... 10 5.5.3 Deep Foundation Quality Control ...... 11 5.5.4 Vibration Monitoring ...... 11 5.6 Infiltration Rates ...... 12 5.7 Pavement Design...... 13 5.7.1 Subgrade Preparation ...... 13 5.7.2 Design Considerations ...... 13 5.7.3 Recommended Minimum Pavement Thickness ...... 14 5.7.4 Pavement Drainage ...... 15 5.7.5 Pavement Maintenance ...... 15 6.0 GENERAL COMMENTS ...... 15

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APPENDIX A – FIELD EXPLORATION Exhibit A-1 — Site Vicinity Map Exhibit A-2 — Exploration Location Diagram Exhibit A-3 — Field Exploration Description Exhibit A-4 — In-Situ Test Record Exhibit A-5 — Hand Auger Boring (HAB) Log Exhibit A-6 — Double Ring Infiltrometer Test Results

APPENDIX B – SUPPORTING DOCUMENTS Exhibit B-1 — General Notes Exhibit B-2 — Unified Soil Classification System

Geotechnical Engineering Report McLeod Plantation ■ Charleston, South Carolina June 19, 2013 ■ Terracon Project No: EN135028R1

EXECUTIVE SUMMARY

This report presents the results of our geotechnical investigation performed for the proposed McLeod Plantation located on the northeast and southeast quadrants of the intersection of Folly Road and Country Club Drive in Charleston, South Carolina. Our geotechnical scope of work for this project included conducting geotechnical fieldwork, associated engineering analysis, and this geotechnical engineering report.

This report provides recommendations for foundation options, seismic considerations, site preparation, and the other geotechnical related conditions that might affect the proposed construction. The following geotechnical considerations were identified during our investigation:

 Based on the presence of potential liquefiable soils, the 2012 International Building Code (IBC) seismic site classification for this site is F. However, if the fundamental period of the structure(s) is less than or equal to 0.5 seconds, the site may reclassify as Class D.

 We estimate that total liquefaction (seismic) induced settlements from the design seismic event may range between 2 to 3 ½ inches with differential settlement approaching 50% to 75% of the total.

 With proper site preparation, the structures may be supported on a shallow foundation system.

 The estimated static settlements will be on the order of 1 inch with differential settlements up to ½ inch.

This summary should be used in conjunction with the entire report for design purposes. It should be recognized that details were not included or fully developed in this section, and the report must be read in its entirety for a comprehensive understanding of the items contained herein. The section titled GENERAL COMMENTS should be read for an understanding of the report limitations.

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GEOTECHNICAL ENGINEERING REPORT MCLEOD PLANTATION CHARLESTON, SOUTH CAROLINA Project No. EN135028 Revision 1 June 19, 2013

1.0 INTRODUCTION

This report presents the results of our geotechnical engineering services performed for the McLeod Plantation. The site is located on the northeast and southeast quadrants of the intersection of Folly Road and Country Club Drive in Charleston, South Carolina.

The project site was explored with a series of six Cone Penetration Tests (CPT) to depths ranging from 30 to 50 feet below the existing ground surface. Adjacent to each in-situ test, a Hand Auger Boring (HAB) was performed and fourteen additional HABs were performed in the parking and event areas. The HABs were advanced to a depth of four feet below the existing ground surface. Additionally, infiltration rates were measured with four Double Ring Infiltration Tests (DRI). The CPT logs, HAB logs, DRI test results, field exploration description, and the boring location diagram are included in Appendix A of this report. The purpose of the study is to provide subsurface information and geotechnical engineering recommendations relative to:

 subsurface soil conditions  foundation options  groundwater conditions  pavement design  seismic evaluation  other geotechnical design parameters  site preparation

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2.0 PROJECT INFORMATION

2.1 Project Description

ITEM DESCRIPTION The proposed improvements are outlined below and consist of three structures, pierhead, parking, and event areas: ■ Welcome Center on the south side of Country Club Drive that is a one-story wood frame structure with parking and drive lanes ■ Pavilion structure that is located on the north side of Country Proposed Improvements Club Drive with associated parking and drive lanes ■ Maintenance building this is a small one-story structure located on the north side of Country Club Drive ■ Pierhead located along Wappoo Creek ■ Event area on the south side of the main house and Country Club Drive ■ Overflow parking on the south side of the property The structural loads are unknown at this time. However, we are assuming the following loading conditions. Structural Loads ■ Columns –50 kips (assumed) ■ Strip – 3 kips per foot (assumed) ■ Floor slabs – 200 psf (assumed) Fill heights are unknown at this time. However, we are assuming Grading minimum fill will be required to achieve finish grade (less than 2 feet)

2.2 Site Location and Description

ITEM DESCRIPTION The project site is located on the northeast and southeast Site Location quadrants of the intersection of Folly Road and Country Club Drive in Charleston, South Carolina. Currently, the site is developed with historic buildings including a Existing improvements plantation house and outbuildings, slave cabins, and a cemetery. Current ground cover Gravel driveway, cultivated grass, and wooded areas Existing topography Relatively flat lying

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3.0 SUBSURFACE CONDITIONS

3.1 Typical Soil Profile

Based on the results of the field exploration, subsurface conditions on the project site can be generalized as follows:

Approximate Depth to Description Material Encountered1 Bottom of Stratum

Stratum 1 3 to 10 inches Topsoil Stratum 2 14 feet Loose to medium dense sand to silty sand Intermittent layers of loose to medium dense silty sand and Stratum 32 33 feet firm silty clay to clayey silt Stratum 43 40 feet Firm to stiff silty clay and clayey silt Stratum 5 43 feet Medium dense sand to silty sand Stratum 64 50 feet + Medium dense silty sand to firm silty clay (Cooper Marl) 1. Material descriptions are based on visual classification from HAB samples and correlations with CPT data 2. Soundings CPT1, CPT3, and CPT5 terminated in this stratum 3. Stratum only encountered in CPT4 and CPT6 4. Soundings CPT2, CPT4, and CPT6 terminated in this stratum

Conditions encountered at each of the test locations are indicated on the individual CPT and HAB logs. Details for each of the tests can be found on the records located in Exhibits A-4 and A-5 located in Appendix A of this report.

3.2 Groundwater

At the time of our exploration, the water table was estimated at depths ranging from 5 to 10 feet below the existing ground surface. The groundwater depths are estimated from CPT pore water pressure data. Groundwater was encountered within HAB12 at an approximate depth of 3 ½ feet below the existing ground surface. The seasonal high groundwater table was only encountered at the DRI4 testing location at 2 feet below the existing ground surface.

Groundwater level fluctuations occur due to seasonal variations in the amount of rainfall, runoff and other factors not evident at the time the borings were performed. Therefore, groundwater levels during construction or at other times in the life of the structure may be higher or lower than the levels indicated on the logs. The possibility of groundwater level fluctuations should be considered when developing the design and construction plans for the project. The groundwater surface should be checked prior to construction to assess its effect on site work and other construction activities.

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4.0 GEOTECHNICAL SEISMIC CONSIDERATIONS

4.1 Seismic Evaluation

According to the International Building Code 2012 edition (IBC 2012), structures are required to avoid collapse during a design earthquake event. The design earthquake has a 50 year exposure period with a 2% probability of exceedance (i.e. a 2500 year design earthquake). The 2500 year design earthquake has a Moment Magnitude (Mw) of 7.3 and a Peak Ground Acceleration (PGA) of 0.32g, as determined by data provided by the IBC 2012 Code. The seismic evaluation of the site identified potentially liquefiable soils at approximate depths between 8 to 25 feet below the ground surface. According to the IBC (2012) and ASCE 7, this potential for liquefaction classifies the site as Site Class F.

ASCE 7 (Section 20.3.1) provides an exception to the Site Class recommendation for structure(s) with a fundamental period equal to or less than 0.5 seconds. This exception states that a site can be classified without considering liquefaction to determine spectral accelerations for structural design. If the proposed structures meet the requirements of the exception Seismic Site Class D would be applicable and the following seismic design parameters can be used for the site:

Code Used Site Classification 2012 International Building Code (IBC)1 D2,3 Seismic Design Parameter Value

Fa 1.00

Fv 1.68

SDS 0.99 g

SD1 0.41 g 1. In general accordance with the 2012 International Building Code, Table 1613.5.2.

2. Based on and average shear wave velocity (Vs) of 813 feet per second (fps) collected during the in-situ testing. The 2012 International Building Code requires a site soil profile determination extending a depth of 100 feet for seismic site classification. Soundings for this project extended to a maximum depth of 50 feet and this seismic site class definition considers that The Cooper Marl is below the maximum depth of the subsurface exploration. 3. Based upon the fundamental period exception outlined in ASCE 7Section 20.3.1. The structural engineer should verify that this assumption is valid for the planned structure.

Figure 1 presents the Design Response Spectrum for the structure for Site Class D calculated by the procedures outlined in IBC 2012/ASCE 7 (Note – This is not a Site Specific Seismic Evaluation).

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0.90

0.80

0.70

0.60

0.50

0.40 0.32 0.30

0.20

0.10 Spectral Response Acceleration, Sa (g) Sa Acceleration, Response Spectral 0.00 0 1 2 3 4 5 Period, T (seconds)

Figure 1. IBC 2012 Site Class D Design Response Spectrum.

4.2 Liquefaction Potential

Due to the high seismicity of the Charleston area of South Carolina, we performed a liquefaction potential analysis for the site to evaluate the stability of the soils. Ground shaking at the foundation of structures and liquefaction of the soil under the foundation are the principal seismic hazards identified for the design of earthquake-resistant structures. Our estimates of liquefaction induced settlements from the design earthquake are 2 to 3 ½ inches. We estimate differential settlements in the range of 50% to 75% of the total. The liquefiable soils were located at depths ranging from 8 to 25 feet below the ground surface. Actual liquefaction settlements at the site would be highly dependent on magnitude and distance from the source during the design earthquake event. If settlements of this magnitude are unacceptable then liquefaction mitigation will be required such as earthquake drains or deep foundation system. However, in our discussions with the structural engineer settlements of this magnitude would be within structural tolerance of the structures, and they can be supported on a shallow foundation system.

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5.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION

5.1 Geotechnical Considerations

Based on the results of our field investigation and experience with similar projects in the area, the proposed structures (Welcome Center, Pavilion, and Maintenance Building) can be supported by shallow foundation system assuming the estimated settlements are within the structural tolerance. The pierhead should be supported by a deep foundation consisting of timber piles or pre-stressed concrete piles.

During the field investigation for the Welcome Center we encountered an anomaly in the test data on the west side of the structure. The data collected for CPT 1 indicates there is a soft zone of organic soils between 5 and 6 ½ feet below the existing ground surface. We performed three additional hand auger boings around the test location for CPT1 to a depth of 7 feet, and did not encounter any soft organic soils. Therefore, we recommend test pits to be performed on the west side of the Welcome Center after the site has been stripped to verify the soils are suitable for shallow foundation support.

The recommendations presented herein have been developed on the basis of the subsurface conditions encountered during field investigation and our understanding of the proposed construction. Should changes in the project criteria occur, a review must be made by Terracon to determine if modifications to our recommendations will be required.

5.2 Earthwork

The following presents recommendations for site and subgrade preparation and the placement of Controlled Fill for this project. Earthwork on the project should be observed and evaluated by Terracon personnel. The evaluation of earthwork should include observation and sufficient testing of Controlled Fill and subgrade preparation, and other geotechnical conditions exposed during the construction of the project.

5.2.1 Site Preparation The initial step in site preparation should be to remove remnant topsoil, organics, and other deleterious material from within the proposed construction area footprints. Stripping should extend a minimum of 5 feet outside the construction area footprints. After stripping test pits should be excavated to a depth of 7 feet on the west side of the Welcome Center to verify no soft organic soils are present. Once the test pits are completed in the Welcome Center and the striping of the other building areas, the existing subgrade should be proofrolled with a loaded tandem axle dump truck or other similar approved construction equipment. A geotechnical engineer or their representative should monitor proofrolling operations. Areas that pump or rut

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excessively should be undercut and reworked or replaced with Controlled Fill. Fill placement may commence after proofrolling has been successfully completed.

5.2.2 Material Types If onsite soils are used as fill they should meet the requirements outlined below. The field investigation identified soils that could be used as Controlled Fill. Controlled fill should meet the following soil property requirements:

1 Acceptable Location for Fill Type USCS Classification Placement Controlled/Imported SP, SP-SM, GP, GW, SW All locations Fill (Passing #200<12%)

Onsite Soils SC, SM Non-structural areas

1. Controlled, compacted fill should consist of approved materials that are free of organic matter and other deleterious debris

5.2.3 Compaction Requirements ITEM DESCRIPTION When heavy, self-propelled sheep’s foot or smooth drum vibratory compaction equipment is used, fill lifts shall have a maximum of 6 to 8 inches in loose thickness. Fill Lift Thickness When hand-guided equipment (i.e. jumping jack or plate compactor) is used, fill lifts shall have a maximum of 2 to 4 inches in loose thickness. 95% of the material’s maximum Modified Proctor dry Compaction Requirements1 density (ASTM D1557) Moisture Content – Controlled Fill or Within the range of ±2% of optimum moisture content value Onsite Soils as determined by the Modified Proctor test. 1. Fill should be tested for moisture content and compaction during placement. If the results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved.

5.3 Shallow Foundation Recommendations

With proper site preparation, the proposed structures (Welcome Center, Pavilion, and Maintenance Building) can be supported by a shallow spread footing foundation system bearing on in-situ soils or properly compacted Controlled Fill. The amount of settlement will be dependent upon fill heights and foundation loads. Design recommendations for shallow foundations for the proposed structure are presented in the following paragraphs.

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5.3.1 Shallow Foundation Design Recommendations DESCRIPTION Column Wall Allowable bearing pressure1 2,000 psf 2,000 psf Minimum dimensions 24 inches 18 inches Minimum embedment below finished grade 12 inches 12 inches Estimated total static settlement2 1 inch 1 inch Estimated differential static settlement2 <1/2 inch between columns <1/2 inch over 30 feet 1. The recommended net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the footing base elevation. This assumes any unsuitable fill, debris or soft soils, if encountered, will be undercut and replaced with Controlled Fill. 2. The settlement estimates are based on a maximum loads of 50 kips for columns, 3 kips per foot for strip footings and the above allowable bearing pressure. The foundation settlement will depend upon the variations within the subsurface soil profile, the structural loading conditions, the embedment depth and dimensions of the footings, the thickness of compacted fill, and the quality of the earthwork operations. These settlement magnitudes assume the foundation subgrade will be prepared as recommended in this report. The settlement calculations were based on maximum footing sizes of 5 ft x 5 ft for columns and 2 ft wide strip footings.

5.3.2 Shallow Foundation Construction Considerations The base of all foundation excavations should be free of water, debris and loose soil prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing soil disturbance. Should the soils at bearing level become excessively dry, disturbed or saturated, the affected soil should be recompacted or removed prior to placing concrete. Place a lean concrete mud-mat over the bearing soils if the excavations must remain open over night or for an extended period of time. It is recommended that the geotechnical engineer be retained to observe and test the soil foundation bearing materials.

If debris or unsuitable bearing soils are encountered in footing excavations, the excavation could be extended deeper to suitable soils and the footing could bear directly on these soils at the lower level or on lean concrete backfill placed in the excavations. As an alternative, the footings could also bear on properly compacted Controlled Fill extending down to the suitable soils. Overexcavation for compacted structural fill placement below footings should extend laterally beyond all edges of the footings at least 8 inches per foot of overexcavation depth below footing base elevation. The overexcavation should then be backfilled up to the footing base elevation with Controlled Fill material placed in lifts of 8 inches or less in loose thickness (6 inches or less if compacted with hand guided equipment) and compacted to at least 95 percent of the material's modified effort maximum dry density (ASTM D1557). The overexcavation and backfill procedure is described in the following figure.

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5.4 Floor Slabs

5.4.1 Floor Slab Design Recommendations Floor slabs can be supported by the in-situ soils or properly compacted Control Fill if prepared as described in section 5.2 Earthwork of this report. Concrete floor slabs constructed on grade can be designed using the modulus of subgrade reaction presented in the following table.

ITEM DESCRIPTION 220 pounds per square inch per inch (psi/in) for Modulus of subgrade reaction point loading conditions

The structural engineer should design the floor slab to limit differential movements between the slab and foundation to reduce the possibility of floor slab cracking. Where appropriate, saw-cut control joints and expansion joints should be placed in the slab to help control the location and extent of cracking. For additional recommendations refer to the ACI Design Manual. Floor slab subgrade should be compacted to 95% of its Modified Proctor maximum dry density (ASTM D698).

The use of a vapor retarder should be considered beneath concrete slabs on grade that will be covered with wood, tile, carpet or other moisture sensitive or impervious coverings, or when the slab will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer and slab contractor should refer to ACI 302 and ACI 360 for procedures and cautions regarding the use and placement of a vapor retarder/barrier.

5.4.2 Floor Slab Construction Considerations On most project sites, the site grading is generally accomplished early in the construction phase. However as construction proceeds, the subgrade may be disturbed due to utility excavations, construction traffic, desiccation, rainfall, etc. As a result, the floor slab subgrade may not be suitable for placement of subbase and concrete and corrective action may be required.

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We recommend the area underlying the floor slab be rough graded and then thoroughly proofrolled with a loaded tandem axle dump truck prior to final grading and placement of subbase. Particular attention should be paid to high traffic areas that were rutted and disturbed earlier and to areas where backfilled trenches are located. Areas where unsuitable conditions are located should be repaired by removing and replacing the affected material with properly compacted fill. All floor slab subgrade areas should be moisture conditioned and properly compacted to the recommendations in this report immediately prior to placement of the subbase and concrete.

5.5 Deep Foundations

Axial capacity of timber piles with an eight inch tip and Pre-stressed Concrete (PSC) piles has been provided for the pierhead. Analysis of the lateral capacity of piles was not performed, and should be evaluated when detailed information becomes available. Additionally, QA/QC recommendations have been provided to ensure proper construction.

5.5.1 Deep Foundation Axial Capacity It is our understanding the pierhead will be supported by piles. Axial and tension capacities of driven piles were calculated using a residual adhesion strength in the Cooper Marl of 2,600 psf. This value is based on our extensive experience with PDA and static load testing in the Cooper Marl Formation. Capacities from soils above the Cooper Marl have been estimated using CPT data correlations. The skin friction was neglected from the loose to dense sands to a depth of 20 feet from the ground surface in the axial and tension capacity analysis. A Factor of Safety (FOS) of 2.25 was used in our calculations which assumes that dynamic testing (i.e. Pile Driving Analyzer (PDA) testing) of two or more test piles will be performed. Allowable axial capacities and tension capacities are presented in the following table.

Allowable Axial Capacities of Piles 8 in Tip Timber Pile 12 in PSC Allowable Axial Allowable Allowable Embedment Embedment Capacity Tension Capacity Tension Depth (ft)1 Depth (ft)1 (ton) Capacity (ton) 25 ton 53 22 482 20 50 ton 74 40 55 38 1. Depth is from existing ground elevation. The Cooper Marl is anticipated to be at 43 feet below the existing ground surface 2. Minimum of 5 feet of embedment into The Cooper Marl

A lateral analysis of the piles can be conducted once the elevation of the ground surface and top of piles at the dock are known. 5.5.2 Deep Foundation Installation Based on our experience with similar projects, air or diesel hammers with a minimum rated energy of 20 to 50 kip-ft should be suitable for pile installation. Pre-augering should be

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conducted to a maximum depth of 20 feet to reduce the driving stresses and vibrations. The outer diameter of the auger used should not exceed the outside dimension of the pile. We recommend a minimum center to center pile spacing of 4 diameters to avoid group effects. Upon selection of the pile size and the contractor’s driving system, a wave equation analysis of piles (WEAP) of the hammer-pile-soil system should be conducted. The WEAP analysis will determine if the selected hammer has sufficient energy to install the selected pile size to the required length, if the driving stresses (both compressive and tensile) during installation are within acceptable limits, and provide pile driving criteria. Hammer and/or pile sizes can be varied until an acceptable hammer-pile system is found. Upon request, Terracon can provide assistance in evaluating the selected hammer and determining the pile driving criteria.

5.5.3 Deep Foundation Quality Control We recommend that at a minimum of two piles be dynamically monitored during installation to evaluate hammer performance and pile driving stresses and integrity. The test piles can be production piles. Where axial capacity is needed, a hammer restrike should be performed on two piles a minimum of seven days after installation to determine final capacity. This wait period will account for the time dependent pile capacity gain (i.e. pile ―setup‖ or ―freeze‖). The piles should be dynamically monitored during installation and hammer restrikes in accordance with ASTM D4945 Standard Test Method for High-Strain Dynamic Testing of Piles.

An engineering technician, supervised by a registered professional engineer, should monitor and document the production pile installations. A pile driving record should be kept for each individual production pile. The individual pile driving records should have the following minimum information:

 Pile size and type

 Final pile embedment depth

 Pile tip and head elevation

 Pile installation date and time

 Pre-augering or spudding information

 Pile blow counts per one (1) foot interval

 Relevant Hammer and Cushion Information

 Hammer Stroke

 Installation notes (as required)

5.5.4 Vibration Monitoring Ground vibrations will be a concern to the existing adjacent structure(s) and should be monitored during pile driving operations. An engineering technician, supervised by a registered professional engineer, should conduct vibration monitoring in conjunction with pile installation monitoring. We

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recommend that the frequency dependent vibration criteria for the Charleston, SC area developed by Hajduk et al. (2004)1 be used for this project. If pile driving vibrations exceed these criteria during installation, pile driving methods should be modified. Modifications can include pre- augering, stroke reduction, or use of a hammer with a smaller rated energy.

In addition, we recommend that a pre-condition and post-condition survey be performed on the buildings on-site and adjacent properties to document existing cracks and other significant defects on adjacent structures both before and after pile installation. The survey would involve photographic records and measurements of existing cracks as well as installation of crack monitoring devices. The surveys should extend a minimum of two to three pile lengths from the proposed pile driving.

5.6 Infiltration Rates

Infiltration rates of the in-situ soils were evaluated at the Welcome Center parking area, event space area, and Pavilion parking area. The infiltration tests were performed at a depth of 12 inches below the existing ground surface. The pond depths are unknown, and once ponds are excavated it may be necessary to perform additional testing due to variations in soils with depth. Infiltration rates varied across the site; therefore, one infiltration rate would not be applicable for the entire site. The seasonal high ground water level was estimated by the mottling of the soils encountered in the hand auger borings, and are presented in the following table. The infiltration rates, as determined by the Double-Ring Test, are summarized in the following table. Infiltration Rates are presented in inches per hour (in/hr).

Double Ring Infiltrometer Test Results Seasonal High Depth of Test Infiltration Rate Test Location Ground Water Table Test Number (in/hr) (ft) (in) DRI-11 Welcome Center Parking Area Greater Than 4 feet 12 24.75 DRI-21 Welcome Center Parking Area Greater Than 4 feet 12 24.22 DRI-31 Adjacent to Event Space Greater Than 4 feet 12 0.39 DRI-4 Parking for Pavilion 2 feet 12 0.88

1 Hajduk, E.L., D.L. Ledford, and W.B. Wright (2004). ―Construction Vibration Monitoring in the Charleston, South Carolina Area‖, Proc. 5th Intern. Conf. on Case Histories in Geo. Engrg., NY.

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5.7 Pavement Design

5.7.1 Subgrade Preparation Pavement subgrades should be carefully evaluated as the time for pavement construction approaches. The moisture content and density of the subgrade should be evaluated and the subgrade proofrolled immediately prior to commencement of base course placement. Yielding or soft areas should be undercut, and should be moisture conditioned and recompacted prior to base course placement as outlined is Section 5.2.3. The base course should be proofrolled immediately prior to commencement of pavement placement. Any soft or yielding areas should be moisture conditioned and recompacted as outlined is Section 5.2.3 prior to pavement placement.

If a significant precipitation event occurs after the evaluation or if the surface becomes disturbed, the subgrade should be reviewed by qualified personnel immediately prior to paving. The subgrade should be in its finished form at the time of the final review. The Graded Aggregate Base Course (GABC) should be compacted to 100% of its Modified Proctor as determined by ASTM D1557.

5.7.2 Design Considerations Based on the anticipated use of the development, we have provided minimum pavement thickness for ―light duty‖ and ―heavy duty‖ traffic areas for a design life of 20 years. ―Light duty‖ pavement is used in parking/drive areas subjected solely to light passenger car and light truck traffic. ―Heavy duty‖ traffic should be used for the main drive lanes in parking areas. Significant differential settlement between the pavements and pedestrian walkways is not anticipated.

The Jaeger Company has informed Terracon that due to deed restrictions placed by the Charleston Historic Society that all pavement surfaces have to be pervious. The pervious pavement surfaces are going to consist of gravel or graded aggregate base course, porous asphalt and possibly porous concrete. Drainage of the pervious pavement systems will be designed by others. The transition between the pervious pavement and impervious pavement areas should consist of a prepared subgrade as described in Section 5.7.1.

The gravel or graded aggregate base course (GABC) will be used in the drive lanes and parking areas. In parking areas the gravel or GABC should be supported by 6 inches of prepared subgrade and in drive lanes the gravel or GABC should be supported by 8 inches of prepared subgrade. The prepared subgrade should be prepared as outlined in Section 5.7.1. A woven geotextile fabric should be used between the GABC and prepared subgrade for separation. The woven geotextile fabric should meet the requirements for SCDOT Class 1 or Class 2 separation. We have only evaluated the pervious pavement system form a strength standpoint. It should be noted that maintenance such as grading and placement of additional stone/GABC will be required; especially in areas that receive turning forces because the material is unbounded.

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The porous asphalt will be used in ADA parking areas and entrance aprons. We recommend that the client verify that the government agency controlling Country Club Drive will allow porous asphalt to be placed with in the right of ways. The SCDOT does not have a design procedure for porous asphalt sections. Therefore, we designed the porous asphalt section by using decreased SCDOT structural numbers, Equivalent Single Axle Loads (ESALs) of 250,000 and CBR value of 12. The porous asphalt should be supported on a working course and free drainage course. The subgrade soils should not be compacted, and a woven geotextile fabric should be placed between the subgrade and drainage course for separation that meet the requirements for SCDOT Class 1 or Class 2 separation.

The Jaeger Company has informed Terracon that porous concrete maybe used for the dumpster pad areas. However, we recommend a traditional concrete slab be used in any areas where dumpsters are to be located in order to provide a more durable wearing surface. In lieu of a traditional concrete slab 10 inches of Macadam Base Course (SCDOT Specifications Section 305.2.1) can be used for the dumpster areas. The Macadam Base Course should be supported by 8 inches of prepared subgrade as outlined in Section 5.7.1. A woven geotextile fabric should be used between the GABC and prepared subgrade for separation, and should meet the aforementioned specifications. If porous concrete is used for the dumpster areas, rails should be placed in the footprint of the dumpster to prevent damage to the porous concrete. The dumpster pad should be large enough to encompass both the dumpster and refuse truck.

5.7.3 Recommended Minimum Pavement Thickness

Free Portland Traffic Porous AC Working SCDOT Total Alternative Drainage Cement Area Course1 Course GABC Thickness Stone Concrete3

Light Pervious ------8.0 8.0 Duty2 Heavy Pervious ------10.0 10.0 Duty2 Aprons & ADA Porous AC 2.0 2.0 12.0 -- -- 16.0 Parking

Trash Container PCC -- -- 6.0 4.0 10.0 Pad3

1. Porous asphalt sections should meet requirements specified by local governing agencies 2. Pervious pavement thickness assumes a separation fabric will be place between the GABC and the subgrade. Gravel can be used in lieu of GABC 3. 4,000 psi at 28 days, 4-inch maximum slump and 5 to 7% air entrained, 6-sack min. mix. PCC pavements are recommended for trash container pads and in any other areas subjected to heavy wheel loads and/or turning traffic. 4. AC: Asphalt Concrete; PCC: Portland Cement Concrete

Responsive ■ Resourceful ■ Reliable 14 Geotechnical Engineering Report McLeod Plantation ■ Charleston, South Carolina June 19, 2013 ■ Terracon Project Number: EN135028

5.7.4 Pavement Drainage Pavements should be sloped to provide rapid drainage of surface water. Water allowed to pond on or adjacent to the pavements could saturate the subgrade and contribute to premature pavement deterioration. In addition, the pavement subgrade should be graded to provide drainage within the granular base section. Appropriate sub-drainage or connection to a suitable daylight outlet should be provided to remove water from the granular subbase.

5.7.5 Pavement Maintenance The pavement sections provided in this report represent minimum recommended thicknesses and, as such, periodic maintenance should be anticipated. Therefore preventive maintenance should be planned and provided for through an on-going pavement management program. Maintenance activities are intended to slow the rate of pavement deterioration, and to preserve the pavement investment. Preventive maintenance is usually the first priority when implementing a pavement maintenance program. Additional engineering observation is recommended to determine the type and extent of a cost effective program. Even with periodic maintenance, some movements and related cracking may still occur and repairs may be required.

6.0 GENERAL COMMENTS

The recommendations presented herein have been developed on the basis of the subsurface conditions encountered during the field investigation and our understanding of the proposed construction. Should changes in the project criteria occur or additional loading information becomes available, a review must be made by Terracon to determine if modifications to our recommendations will be required.

Terracon should be retained to review the final design plans and specifications so comments can be made regarding interpretation and implementation of our geotechnical recommendations in the design and specifications. Terracon also should be retained to provide observation and testing services during site preparations and grading, and other earth-related construction phases of the project.

The analysis and recommendations presented in this report are based upon the data obtained from the borings/soundings performed at the indicated locations and from other information discussed in this report. This report does not reflect variations that may occur between borings, across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided.

Responsive ■ Resourceful ■ Reliable 15 Geotechnical Engineering Report McLeod Plantation ■ Charleston, South Carolina June 19, 2013 ■ Terracon Project Number: EN135028

The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. Terracon can perform these services on request.

This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, either expressed or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing.

Responsive ■ Resourceful ■ Reliable 16

APPENDIX A

Exhibit A-1 Site Vicinity Map Exhibit A-2 Exploration Location Diagram Exhibit A-3 Field Exploration Description Exhibit A-4 In-Situ Testing Record Exhibit A-5 Hand Auger Boring (HAB) Log Exhibit A-6 Double Ring Infiltrometer Test Results

Responsive ■ Resourceful ■ Reliable Appendix A SITE LOCATION

PROJECT MNGR: PROJECT NO. JA EN135028 SITE VICINITY EXHIBIT: DRAWN BY: SCALE: CS NA CHECKED BY: FILE NO. McLEOD PLANTATION JA NA A-1 APPROVED BY: DATE: 1450 FIFTH STREET WEST NORTH CHARLESTON, SC JA APR 12, 2013 PH: (843) 884-1234 FAX: (843) 884-9234 CHARLESTON SOUTH CAROLINA C P T H 6 D L A R E B I G 4 7 E N C D H S C D 1 I NC H = 20 F EET P E O A O T I N U N S 5 D B E M H

A I P A E C U C E B

R C G N P 6 I O T E E N 4 T N R G R C E

B I A H P

N P O T T A F E R I 3 B I O N L I N 5 N T E G R

T T

O R ( E H A M S A T T E B I

T O ( - C ) E N P R

T T

( E - D ) S R T D I -

H R ) ( S A I 2 C B P 4 T H - C D P A ) A R P H R P O E A R C W J E B O K N C E V

B T D E

Y H M 1 D B :

N Y B H 7 : G Y A : R : A C S B B P C 3 C J J J A A A 1 S T P D 5 1 T R F D S P I C R A L 2 H E T A O I E L N J E 1 : E O H A : C A . T

P N H A B O R E .

N A B 1 1 2 1 6 , 3 B 1

2 5 0 0 N N 2 1 2 A A 3 8 P 1 4 H 5 : 0

(

8 F 4 I F 3 T )

H 8

8 S 4 T - R 1 2 E 3 E 4 T

W E S T N O R T F H H A

C X H :

( A A H 8 R 4 L 3 E ) B A

S 8 8 T 4 O 8 - B N 9 , 2

S 3 C 9 4 C H A R L E S H T H A O A N B B D 1 1 1 R 0 I 3 M c B L O H E R I N A O G H B

E D A X 1 P

B 2 L P O 1 R L 3 A A T I O N N

T D I A A G H T R A A I M O B 1 N 4 S O U T H

C A R O L I N A E A X H - I B 2 I T : Geotechnical Engineering Report McLeod Plantation ■ Charleston, South Carolina April 17, 2013 ■ Terracon Project Number: EN135028

Field Exploration Description Subsurface conditions were explored by advancing six in-situ tests to depths of about 30 to 50 feet and tweenty hand auger borings to a depth of about 4 feet. In addition to the soundings and hand auger borings, four double ring infiltration tests were performed at a depth of twelve inches below the existing ground surface. The approximate locations of the tests are indicated on the Exploration Location Diagram on Exhibit A-2 in Appendix A. The field exploration was performed on March 21 and March 22, 2013. The test location was selected by Terracon personnel using aerial drawing and existing landmarks. The boring locations should be considered accurate only to the degree implied by the methods employed to determine them.

The in-situ test consisted of six Cone Penetration Tests (CPT), which were advanced with a track mounted Pagani 220-73 rig. Adjacent to the soundings and in the parking areas and event areas, we also performed Hand Auger Borings (HAB) to a depth of approximately 4 feet. Samples were taken from the HABs sealed to reduce moisture loss, and taken to the laboratory for further examination, testing, and classifications. Four Double Ring Infiltration test (DRI) were performed at a depth of twelve inches below the existing ground surface.

The driller’s logs and recovered samples were compiled and reviewed by the geotechnical engineer in order to produce the sounding and HAB logs. The sounding logs, HAB logs, and DRI results are presented on Exhibit A-4 through A-6 in Appendix A. General notes and soil classification procedures for the soundings and HAB are presented on Exhibit C-1 in Appendix C.

Responsive ■ Resourceful ■ Reliable Exhibit A-3 CPT LOG NO. C1 Page 1 of 1 PROJECT: McLeod Plantation CLIENT: The Jaeger Company TEST LOCATION: See Exhibit A-2 Gainesville, GA SITE: Country Club Drive and Folly Road Charleston, SC Hydrostatic Pressure Material Description Depth Tip Resistance, qt Sleeve Friction, fs Pore Pressure Friction Ratio Depth (ft) (tsf) (tsf) (tsf) (%) Normalized CPT Soil Behavior Type (ft) (Robertson et al. 2010) 20 40 60 80 0.5 1.0 1.5 2.0 0 1 2 3 1 2 3 4 0 0

Sands - clean sand to silty sand 5 5 >> Sands - clean sand to silty sand 10 10

>> Sands - clean sand to silty sand 15 15

20 20 Sands - clean sand to silty sand

25 25

30 >> CPT Terminated at 30.1 Feet 30

35 35

40 40

45 45

50 50

See Exhibit A-3 for description of field procedures. Organic, soils, peats Clays: clay to silty clay Silt mixtures; clayey silt to silty clay See Appendix C for explanation of symbols and abbreviations as well as the correlations used in the CPT data interpretation. Sand mixtures; silty sand to sandy silt Sands; clean sand to silty sand Gravelly sand to sand

WATER LEVEL OBSERVATION Notes: CPT Started: 3/21/2013 CPT Completed: 3/21/2013 Probe no. 4526 with net area ratio of 0.86 8 ft estimated water depth Rig: Pagani TG73-200 Operator: R. Frazier (used in normalizations and correlations; 1450 5th Street West see Appendix C) North Charleston, South Carolina Project No.: EN135028 Exhibit: A-4 THIS TEST RECORD IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. SMART CPT REPORT PLANTATION EN135028 MCLEOD 2.GPJ TERRACON2012_W - INSITU.GDT 4/15/13 CPT LOG NO. C3 Page 1 of 1 PROJECT: McLeod Plantation CLIENT: The Jaeger Company TEST LOCATION: See Exhibit A-2 Gainesville, GA SITE: Country Club Drive and Folly Road Charleston, SC Hydrostatic Pressure Material Description Depth Tip Resistance, qt Sleeve Friction, fs Pore Pressure Friction Ratio Depth (ft) (tsf) (tsf) (tsf) (%) Normalized CPT Soil Behavior Type (ft) (Robertson et al. 2010) 20 40 60 80 0.5 1.0 1.5 2.0 0 1 2 3 1 2 3 4 0 0

5 5

Sands - clean sand to silty sand 10 10 >>

15 15

Sands - clean sand to silty sand >> 20 >> Sands - clean sand to silty sand 20

25 25

30 CPT Terminated at 30.1 Feet 30

35 35

40 40

45 45

50 50

WATER LEVEL OBSERVATION Notes: CPT Started: 3/21/2013 CPT Completed: 3/21/2013 Probe no. 4526 with net area ratio of 0.86 10 ft estimated water depth Rig: Pagani TG73-200 Operator: R. Frazier (used in normalizations and correlations; 1450 5th Street West see Appendix C) North Charleston, South Carolina Project No.: EN135028 Exhibit: A-4 THIS TEST RECORD IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. SMART CPT REPORT PLANTATION EN135028 MCLEOD 2.GPJ TERRACON2012_W - INSITU.GDT 4/15/13 CPT LOG NO. C4 Page 1 of 1 PROJECT: McLeod Plantation CLIENT: The Jaeger Company TEST LOCATION: See Exhibit A-2 Gainesville, GA SITE: Country Club Drive and Folly Road Charleston, SC Hydrostatic Pressure Material Description Depth Tip Resistance, qt Sleeve Friction, fs Pore Pressure Friction Ratio Depth (ft) (tsf) (tsf) (tsf) (%) Normalized CPT Soil Behavior Type (ft) (Robertson et al. 2010) 20 40 60 80 0.5 1.0 1.5 2.0 0 1 2 3 1 2 3 4 0 0

5 5 Sands - clean sand to silty sand

10 10

15 15

20 20

25 25

30 30

Silt mixtures - clayey silt to silty clay 35 35

40 Silt mixtures - clayey silt to silty clay 40

45 >> 45

50 CPT Terminated at 50.1 Feet 50

WATER LEVEL OBSERVATION Notes: CPT Started: 3/21/2013 CPT Completed: 3/21/2013 Probe no. 4526 with net area ratio of 0.86 8 ft estimated water depth Rig: Pagani TG73-200 Operator: R. Frazier (used in normalizations and correlations; 1450 5th Street West see Appendix C) North Charleston, South Carolina Project No.: EN135028 Exhibit: A-4 THIS TEST RECORD IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. SMART CPT REPORT PLANTATION EN135028 MCLEOD 2.GPJ TERRACON2012_W - INSITU.GDT 4/15/13 CPT LOG NO. C5 Page 1 of 1 PROJECT: McLeod Plantation CLIENT: The Jaeger Company TEST LOCATION: See Exhibit A-2 Gainesville, GA SITE: Country Club Drive and Folly Road Charleston, SC Hydrostatic Pressure Material Description Depth Tip Resistance, qt Sleeve Friction, fs Pore Pressure Friction Ratio Depth (ft) (tsf) (tsf) (tsf) (%) Normalized CPT Soil Behavior Type (ft) (Robertson et al. 2010) 20 40 60 80 0.5 1.0 1.5 2.0 0 1 2 3 1 2 3 4 0 0

Sands - clean sand to silty sand 5 5

Sands - clean sand to silty sand 10 10 >> >> Sands - clean sand to silty sand 15 15

>> >> 20 20

25 25

30 CPT Terminated at 30.1 Feet 30

35 35

40 40

45 45

50 50

WATER LEVEL OBSERVATION Notes: CPT Started: 3/21/2013 CPT Completed: 3/21/2013 Probe no. 4526 with net area ratio of 0.86 8 ft estimated water depth Rig: Pagani TG73-200 Operator: R. Frazier (used in normalizations and correlations; 1450 5th Street West see Appendix C) North Charleston, South Carolina Project No.: EN135028 Exhibit: A-4 THIS TEST RECORD IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. SMART CPT REPORT PLANTATION EN135028 MCLEOD 2.GPJ TERRACON2012_W - INSITU.GDT 4/15/13 CPT LOG NO. C6 Page 1 of 1 PROJECT: McLeod Plantation CLIENT: The Jaeger Company TEST LOCATION: See Exhibit A-2 Gainesville, GA SITE: Country Club Drive and Folly Road Charleston, SC Hydrostatic Pressure Material Description Depth Tip Resistance, qt Sleeve Friction, fs Pore Pressure Friction Ratio Depth (ft) (tsf) (tsf) (tsf) (%) Normalized CPT Soil Behavior Type (ft) (Robertson et al. 2010) 20 40 60 80 0.5 1.0 1.5 2.0 0 1 2 3 1 2 3 4 0 0

5 5 Sands - clean sand to silty sand

10 10 Sand mixtures - silty sand to sandy silt

15 15

20 20

25 25 >>

30 Silt mixtures - clayey silt to silty clay 30

35 35

40 Sands - clean sand to silty sand 40

45 Sand mixtures - silty sand to sandy silt 45

Sand mixtures - silty sand to sandy silt 50 CPT Terminated at 50.1 Feet 50

WATER LEVEL OBSERVATION Notes: CPT Started: 3/21/2013 CPT Completed: 3/21/2013 Probe no. 4526 with net area ratio of 0.86 5 ft estimated water depth Rig: Pagani TG73-200 Operator: R. Frazier (used in normalizations and correlations; 1450 5th Street West see Appendix C) North Charleston, South Carolina Project No.: EN135028 Exhibit: A-4 THIS TEST RECORD IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. SMART CPT REPORT PLANTATION EN135028 MCLEOD 2.GPJ TERRACON2012_W - INSITU.GDT 4/15/13 CPT LOG NO. SCPT2 Page 1 of 1 PROJECT: McLeod Plantation CLIENT: The Jaeger Company TEST LOCATION: See Exhibit A-2 Gainesville, GA SITE: Country Club Drive and Folly Road Charleston, SC Hydrostatic Pressure Material Description Depth Tip Resistance, qt Sleeve Friction, fs Pore Pressure Friction Ratio Depth (ft) (tsf) (tsf) (tsf) (%) Normalized CPT Soil Behavior Type (ft) (Robertson et al. 2010) 20 40 60 80 0.5 1.0 1.5 2.0 0 1 2 3 1 2 3 4 0 0

5 Sands - clean sand to silty sand 5

10 10

>> Sands - clean sand to silty sand 15 >> 15 >>

20 20

>> 25 25

Sand mixtures - silty sand to sandy silt

30 Sand mixtures - silty sand to sandy silt 30

>> 35 >> 35 >> >> >> 40 >> 40

CPT Terminated at 42.7 Feet 45 45

50 50

WATER LEVEL OBSERVATION Notes: CPT Started: 3/21/2013 CPT Completed: 3/21/2013 Probe no. 4156 with net area ratio of 0.57 7 ft estimated water depth Rig: Pagani TG73-200 Operator: R. Frazier (used in normalizations and correlations; 1450 5th Street West see Appendix C) North Charleston, South Carolina Project No.: EN135028 Exhibit: A-4 THIS TEST RECORD IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. SMART CPT REPORT PLANTATION EN135028 MCLEOD 2.GPJ TERRACON2012_W - INSITU.GDT 4/15/13 HAND AUGER BORING

3/21/2013 to Project Name: Date: McLeod Plantation 3/22/2013 Project Number: EN135024 Engineer: JA East side of Intersection of Folly Road and Project Location: Supervisor: MB Country Club Drive, Charleston SC

Depth Soil Stratigraphy Test (inches) Description and Remarks USCS Number Classification From To %<#200 % Moisture LL/PI

0 3 Topsoil Dark brown Sand 3 20 SP HAB at %<#200=4%, %Moisture=8% CPT 1 20 48 Tan Sand SP

Groundwater Was Not Encountered at the Time of Boring

0 3 Topsoil

HAB at 3 24 Dark brown Sand SP SCPT 2 24 48 Tan Sand SP

Groundwater Was Not Encountered at the Time of Boring

0 8 Topsoil with roots HAB at Tan and brown Sand 8 48 SP CPT 3 %<#200=2%, %Moisture=5% Groundwater Was Not Encountered at the Time of Boring

0 8 Topsoil with roots HAB at 8 48 Tan and brown Sand SP CPT 4 Groundwater Was Not Encountered at the Time of Boring

0 3 Topsoil with roots HAB at 3 48 Tan and brown Sand SP CPT 5 Groundwater Was Not Encountered at the Time of Boring

Exhibit A-5 HAND AUGER BORING

Depth Soil Stratigraphy Test (inches) Description and Remarks USCS Number Classification From To %<#200 % Moisture LL/PI

0 3 Topsoil with roots Brown and tan Sand with silt 3 26 SP-SM HAB at %<#200=6%, %Moisture=7% CPT 6 26 48 Dark tan and brown Sand SP

Groundwater Was Not Encountered at the Time of Boring

0 4 Topsoil with roots

HAB 1 4 48 Brown and tan Sand SP

Groundwater Was Not Encountered at the Time of Boring

0 4 Topsoil with roots Brown and tan Sand HAB 2 4 48 SP %<#200=1%, %Moisture=4% Groundwater Was Not Encountered at the Time of Boring

0 3 Topsoil with roots HAB 3 3 48 Brown and tan Sand SP Groundwater Was Not Encountered at the Time of Boring

0 5 Topsoil with roots HAB 4 5 48 Brown and tan Sand SP Groundwater Was Not Encountered at the Time of Boring

0 10 Topsoil with roots HAB 5 10 48 Tan and brown Sand SP Groundwater Was Not Encountered at the Time of Boring

Exhibit A-5 HAND AUGER BORING

Depth Soil Stratigraphy Test (inches) Description and Remarks USCS Number Classification From To %<#200 % Moisture LL/PI

0 5 Topsoil with roots

HAB 6 5 48 Tan and brown Sand SP

Groundwater Was Not Encountered at the Time of Boring

0 3 Topsoil with roots

3 30 Tan Sand SP HAB 7 30 48 Brown and reddish brown Sand with cemented sand layers SP

Groundwater Was Not Encountered at the Time of Boring

0 38 Tan and brown Sand SP HAB 8 38 48 Brown Sand with cemented sand layers SP-SM Groundwater Was Not Encountered at the Time of Boring

0 12 Brown Sand with roots SP Brown Sand with silt 12 18 SP-SM HAB 9 %<#200=9%, %Moisture=10% 18 48 Tan and reddish brown Sand SP-SM Groundwater Was Not Encountered at the Time of Boring

0 4 Brown Sand with roots 4 18 Brown Sand with silt SP-SM HAB 10 Tan to reddish brown Sand with cemented sand layers 18 48 SP-SM %<#200=12%, %Moisture=14% Groundwater Was Not Encountered at the Time of Boring

Exhibit A-5 HAND AUGER BORING

Depth Soil Stratigraphy Test (inches) Description and Remarks USCS Number Classification From To %<#200 % Moisture LL/PI

0 28 Dark brown Sand with silt SP-SM

28 36 Tan Sand with silt SP-SM HAB 11 36 48 Tan to reddish brown Sand with cemented sand layers SP-SM

Groundwater Was Not Encountered at the Time of Boring

0 10 Dark tan silty Sand SM Tan clayey Sand 10 24 SC HAB 12 %<#200=22%, %Moisture=15% 24 48 Tan and gray clayey sand SC

Groundwater Encountered at 43 Inches at the Time of Boring

0 18 Dark tan silty Sand SM 18 32 Tan clayey Sand SC HAB 13 38 48 Tan and brown clayey Sand SC Groundwater Was Not Encountered at the Time of Boring

0 5 Dark Tan silty Sand with roots SM 5 20 Dark tan silty Sand SM

HAB 14 20 32 Tan clayey Sand SC Tan and brown clayey Sand 32 48 SC %<#200=40%, %Moisture=26%, LL/PI=39/20 Groundwater Was Not Encountered at the Time of Boring

Exhibit A-5 HAND AUGER BORING

Project Name: McLeod Plantation Date: 4/8/2013

Project Number: EN135024 Engineer: JA East side of Intersection of Folly Road and Project Location: Supervisor: MB Country Club Drive, Charleston SC

Depth Soil Stratigraphy Test (inches) Description and Remarks USCS Number Classification From To %<#200 % Moisture LL/PI

0 3 Topsoil

3 18 Dark brown Sand SP HAB 15 at 18 74 Tan Sand SP CPT 1 74 84 Tan and brown Sand, wet SP

Groundwater Was Encountered at 78 Inches at the Time of Boring

0 4 Topsoil

4 20 Dark brown Sand SP HAB 16 adjacent to 20 73 Tan Sand SP CPT 1 73 84 Tan Sand, wet SP

Groundwater Was Encountered at 77 Inches at the Time of Boring

0 4 Topsoil

HAB 17 4 20 Dark brown Sand SP adjacent to 20 64 Tan Sand SP CPT 1 64 84 Tan Sand, wet SP Groundwater Was Encountered at 64 Inches at the Time of Boring

Exhibit A-5 Infiltration Rate of Soils Using Double Ring Infiltrometer ASTM D3385-09

Project Name McLeod Plantation Technician B. Rozier Project Number EN135028 Engineer J Ard Test Number: DRI-1 Weather Conditions Cloudy Test Location: Welcome Center Parking Temperature 54 Date 3/21/2013 Testing Liquid Water Double Ring Infiltrometer Parameters Area of Inner Ring (cm2): 730 cm2 Depth of Water (Inner Ring): 4 in. Area if Annular Space (cm2): 2189 cm2 Depth of Water (Annular Space): 4 in.

80.0 Incremental Time Cumulative Flow Incremental Infiltration Soil Profile (min) (cm3) (cm/hr) 5 3,000 49 Depth (in.) Description 70.0 5 7,000 66 0 to 4 Top soil 5 11,000 66 60.0 5 14,800 62 4 to 48 Tan silty Sand 5 18,800 66 5 22,650 63 50.0 No groundwater encountered 5 26,250 59 5 30,050 62 Note: Soils indicating seasonal high groundwater were not 40.0 5 33,800 62 encountered 5 37,750 65 5 41,750 66 30.0 5 45,700 65 5 49,700 66 20.0 Infiltration Velocity (cm/h) Infiltration Velocity Average (cm/hr) 62.87 Average (in/hr) 24.75 10.0

0.0 0 20406080

Elapsed Time (min) Infiltration Rate of Soils Using Double Ring Infiltrometer ASTM D3385-09

Project Name McLeod Plantation Technician B. Rozier Project Number EN135028 Engineer J Ard Test Number: DRI-2 Weather Conditions Cloudy Test Location: Welcome Center Parking Temperature 50 Date 3/21/2013 Testing Liquid Water Double Ring Infiltrometer Parameters Area of Inner Ring (cm2): 730 cm2 Test Depth: 12 in Depth of Water (Inner Ring): 4 in. Area if Annular Space (cm2): 2189 cm2 Ring Seating Depth: 4 in Depth of Water (Annular Space): 4 in.

90.0 Incremental Time Cumulative Flow Incremental Infiltration Soil Profile (min) (cm3) (cm/hr) 80.0 5 4,880 80 Depth (in.) Description 5 8,580 61 0 to 4 Top soil 5 12,380 62 70.0 5 16,030 60 4 to 48 Tan and brown silty Sand 5 19,780 62 60.0 5 23,380 59 No groundwater encountered 5 26,930 58 50.0 5 30,380 57 5 33,730 55 Note: Soils indicating seasonal high groundwater were not encountered 40.0 5 37,530 62 5 41,130 59 30.0 5 44,830 61 5 48,630 62 20.0 Infiltration Velocity (cm/h) Velocity Infiltration

Average (cm/hr) 61.52 10.0 Average (in/hr) 24.22 0.0 0 20406080

Elapsed Time (min) Infiltration Rate of Soils Using Double Ring Infiltrometer ASTM D3385-09

Project Name McLeod Plantation Technician B. Rozier Project Number EN135028 Engineer J Ard Test Number: DRI-3 Weather Conditions Cloudy Test Location: Adjacent to Event Area Temperature 48 Date 3/21/2013 Testing Liquid Water Double Ring Infiltrometer Parameters Area of Inner Ring (cm2): 730 cm2 Test Depth: 12 in Depth of Water (Inner Ring): 4 in Area if Annular Space (cm2): 2189 cm2 Ring Seating Depth: 4 in Depth of Water (Annular Space): 4 in

1.8 Incremental Time Cumulative Flow Incremental Infiltration Soil Profile (min) 3 (cm/hr) (cm ) 1.6 5 100 1.64 Depth (in.) Description 5 140 0.66 0 to 14 Dark tan silty Sand 1.4 5 230 1.48 5 260 0.49 14 to 36 Tan Sand 1.2 5 320 0.99 5 380 0.99 36 to 48 Brown silty clayey Sand 5 440 0.99 1.0 5 480 0.66 No groundwater encountered 5 570 1.48 0.8 5 590 0.33 Note: Soils indicating seasonal high groundwater were not encountered 5 670 1.32 0.6 5 730 0.99 0.4 Infiltration Velocity (cm/h) Velocity Infiltration Average (cm/hr) 1.00 0.2 Average (in/hr) 0.39

0.0 0 20406080 Elapsed Time (min) Infiltration Rate of Soils Using Double Ring Infiltrometer ASTM D3385-09

Project Name McLeod Plantation Technician B. Rozier Project Number EN135028 Engineer J Ard Test Number: DRI-4 Weather Conditions Cloudy Test Location: Parking for Pavillion Temperature 47 Date 3/21/2013 Testing Liquid Water Double Ring Infiltrometer Parameters Area of Inner Ring (cm2): 730 cm2 Test Depth: 12 in Depth of Water (Inner Ring): 4 in Area if Annular Space (cm2): 2189 cm2 Ring Seating Depth: 4 in Depth of Water (Annular Space): 4 in

4.0 Incremental Time Cumulative Flow Incremental Infiltration Soil Profile (min) (cm3) (cm/hr) 5 150 2.47 Depth (in.) Description 3.5 5 380 3.78 0 to 4 Top soil 5 480 1.64 3.0 5 640 2.63 4 to 24 Tan and trace orange Sand 5 790 2.47 5 900 1.81 2.5 24 to 48 Light gray Sand 5 1,020 1.97 5 1,120 1.64 No groundwater encountered; 2.0 5 1,240 1.97 Seasonal high groundwater located at 24 inches 5 1,380 2.30 1.5 5 1,500 1.97 5 1,640 2.30 5 1,760 1.97 1.0 Infiltration Velocity (cm/h) Velocity Infiltration

Average (cm/hr) 2.23 0.5 Average (in/hr) 0.88 0.0 0 20406080

Elapsed Time (min)

APPENDIX B

Exhibit B-1 General Notes Exhibit B-2 Unified Soil Classification System

Responsive ■ Resourceful ■ Reliable Appendix B

General Notes

Cone Penetration Classification

The tip resistance (qc) is measured as the maximum force over the projected area of the tip. It is a point stress related to the bearing capacity of the soil. The measured qc must be corrected for porewater pressure effects (Lunne et al, 1997), especially in clays and silts where porewater pressures typically vary greatly from hydrostatic. This corrected value is known as qt,, which is reported in the Piezocone Penetration Logs. The u2 position element is required for the measurement of penetration porewater pressures and the correction of tip resistance. The sleeve friction (fs) is used as a measure of soil type and can be expressed by friction ratio:

FR = fs/qt.

The estimated stratigraphic profiles included in the Piezocone Penetration Logs are based on relationships between qt, fs, and U2. The normalized friction ratio (FRN) is calculated by using:

f FR  s 100% N q  ' t vo and is indicative of soil behavior and is used to classify the soil behavior type. Typically, cohesive soils, such as plastic silts and clays, have high FR values, low qt values, and generate large excess penetration porewater pressures. Cohesionless soils, such as sands, have lower FR's, high qt values, and typically do not generate excess penetration porewater pressures. The following graph (Robertson, 1990) presents one of the accepted correlations used to classify soils behavior types.

Seismic Cone Penetration Testing (SCPT’s) The Seismic Piezocone Penetration Test (SCPTu) is identical to the CPTu test with added instrumentation to determine shear wave velocity with depth. In SCPTu, the shear wave velocity is collected via an accelerometer placed above the instrumented cone. A shear wave is generated at the ground surface, such as a hammer striking a steel plate on the end, which propagates through the soil and is recorded by the accelerometer at selected intervals (typically 1 meter). From this data, the interval shear wave velocities of the soil are calculated. These interval velocities are used to develop the shear wave velocity profile for the site, which is presented in the report Appendix. Soil shear wave velocity data is used in evaluation of liquefaction potential, site class determination, site specific analyses, and other geotechnical design applications.

Flat Blade Dilatometer Testing The Flat Blade Dilatometer Test (DMT) consists of hydraulically pushing a flat steel blade along a series of rods to a desired depth. The blade is a 3.75 inch wide by 0.55 inch thick with a 2.4 inch circular membrane near the center. Every 8 inches in depth, the steel membrane is inflated using gas pressure while two measurements are recorded: A = the pressure at which the membrane starts to expand and B = pressure required to deflect the membrane 1.1 millimeters (1/16 inches) into the surrounding soil. A series of these pressure measurements performed at varying depths is typically called a DMT sounding. Through developed correlations with the pressure measurements, many geotechnical design parameters can be calculated including: the Dilatometer Modulus (ED), material type, Constrained Modulus (M), shear strength parameters, and horizontal and vertical stresses. These parameters are used to create a strength profile for the soil that can be used in many facets of geotechnical design. DMT testing is performed in accordance with ASTM D6635 Standard Test Method for Performing the Flat Plate Dilatometer. Responsive ■ Resourceful ■ Reliable Exhibit B-1

A schematic of the front and side profile of the Flat Blade Dilatometer

Hand Auger Borings (HAB’s) Hand Auger Borings (HAB’s) allow for physical sampling of the subgrade soils for visual classification and site preparation recommendations.

Responsive ■ Resourceful ■ Reliable Exhibit B-1

UNIFIED SOIL CLASSIFICATION SYSTEM

Soil Classification A Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Group Group Name B Symbol E F Gravels: Clean Gravels: Cu  4 and 1  Cc  3 GW Well-graded gravel C F More than 50% of Less than 5% fines Cu  4 and/or 1  Cc  3 E GP Poorly graded gravel F,G,H coarse fraction retained Gravels with Fines: Fines classify as ML or MH GM Silty gravel Coarse Grained Soils: C F,G,H on No. 4 sieve More than 12% fines Fines classify as CL or CH GC Clayey gravel More than 50% retained E SW Well-graded sand I on No. 200 sieve Sands: Clean Sands: Cu  6 and 1  Cc  3 D I 50% or more of coarse Less than 5% fines Cu  6 and/or 1  Cc  3 E SP Poorly graded sand G,H,I fraction passes No. 4 Sands with Fines: Fines classify as ML or MH SM Silty sand D sieve More than 12% fines Fines classify as CL or CH SC Clayey sand G,H,I PI  7 and plots on or above “A” line J CL Lean clay K,L,M Inorganic: J K,L,M Silts and Clays: PI  4 or plots below “A” line ML Silt Liquid limit less than 50 Liquid limit - oven dried Organic clay K,L,M,N Organic:  0.75 OL Fine-Grained Soils: Liquid limit - not dried Organic silt K,L,M,O 50% or more passes the PI plots on or above “A” line CH Fat clay K,L,M No. 200 sieve Inorganic: K,L,M Silts and Clays: PI plots below “A” line MH Elastic Silt Liquid limit 50 or more Liquid limit - oven dried Organic clay K,L,M,P Organic:  0.75 OH Liquid limit - not dried Organic silt K,L,M,Q Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat

A Based on the material passing the 3-in. (75-mm) sieve H If fines are organic, add “with organic fines” to group name. B If field sample contained cobbles or boulders, or both, add “with cobbles I If soil contains  15% gravel, add “with gravel” to group name. or boulders, or both” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly whichever is predominant. graded gravel with silt, GP-GC poorly graded gravel with clay. L If soil contains  30% plus No. 200 predominantly sand, add “sandy” to D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded group name. sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded M If soil contains  30% plus No. 200, predominantly gravel, add sand with silt, SP-SC poorly graded sand with clay “gravelly” to group name. 2 N (D ) PI  4 and plots on or above “A” line. E 30 O Cu = D60/D10 Cc = PI  4 or plots below “A” line. P D10 x D60 PI plots on or above “A” line. Q F If soil contains  15% sand, add “with sand” to group name. PI plots below “A” line. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.