Appendix A - Geotechnical Report.pdf

Geotechnical Report

USACE –Eight Bed Level 1 Confinement Facility Joint Base McGuire-Dix-Lakehurst Burlington County, New Jersey

Submitted to:

Burns & McDonnell Engineering Company 10 N. Park Place Morristown, New Jersey

Submitted by:

GEI Consultants, Inc.

300 Broadacres Dr Suite 100, Bloomfield, NJ 07003 973-873-7110

January 2022 Project 2104189

Sean T. DiBartolo, P.E. (NJ), CFM Senior Geotechnical Engineer

Jeanne A. LeFebvre, P.E. (MA) Geotechnical Project Manager sdibartolo GEI Report Watermark sdibartolo Stamp sdibartolo Image

USACE –Eight Bed Level 1 Confinement Facility Joint Base McGuire-Dix-Lakehurst Burlington County, New Jersey January 2022

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Table of Contents

Executive Summary iii

1. Introduction 1

1.1 Scope of Services 1

1.2 Authorization 2

1.3 GEI Team 2

1.4 Elevation Datum and Horizontal Coordinate System 2

1.5 Site and Project Description 2

2. Subsurface Explorations 3

2.1 Subsurface Explorations 3

2.1.1 Test Pits 3

2.1.2 Geotechnical Test Borings 3

3. Subsurface Conditions 5

3.1 Geologic Setting 5

3.2 Subsurface Conditions 5

3.3 Groundwater Conditions 6

3.4 In-situ Permeability Testing 6

3.5 USDA Soil Texture, NRCS Hydrologic Soil Group, and Infiltration Rate 7

3.6 Laboratory Testing 7

3.6.1 Geotechnical Testing 7

3.6.2 Corrosivity Indicators Testing 8

3.7 Sample Storage and Disposition 8

4. Geotechnical Recommendations 9

4.1 Foundation Design 9

4.2 Floor Slab Design 9

4.3 Wall Design 10

4.4 Seismic Design and Liquefaction 11

4.4.1 Seismic Design Parameters 11

4.4.2 Liquefaction Triggering Analysis 12

4.4.2.1 Triggering Analysis using SPT Data 12

4.4.2.2 Recommendations 12

4.5 Frost Depth 13

4.6 Soil Corrosivity 13

4.7 Pavement Design 14

4.7.1 Flexible Pavements 14

4.7.2 Rigid Pavements 15

4.8 Karst Potential and Expansive Conditions 15

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5. Construction Considerations 16

5.1 Subgrade Preparation 16

5.1.1 Removal of Surface Materials 16

5.1.2 Removal/Re-routing of Utilities 16

5.1.3 Foundations 16

5.1.4 Slabs-on-Grade 16

5.2 Excavation Support and Dewatering 17

5.3 Freezing Conditions 17

5.4 Backfilling and Compaction 17

5.5 Site Disturbance 18

6. Limitations 19

7. References 20

Tables

1. Subsurface Exploration Data

2. Equivalent SPT N-Values

3. Recommended Geotechnical Design Parameters

4. Constant Head Field Permeameter Data

5. USDA Soil Texture, NRCS Soil Group, and Infiltration Rate

6. Corrosivity Indicators Data Summary

Figures

1. Site Location Map

2. Exploration Location Plan

3. USDA Soil Texture Triangle

4. Recommended Lateral Earth Pressures and Retaining Wall Drainage Detail

5. Passive Later Earth Pressures for Grade Beam or Wall Footing

6. Liquefaction Triggering Analysis Results: SPTs

Appendices A. Exploration Logs B. Laboratory Testing Results JP/STD/JAL:vjb

B:\Working\BURNS AND MCDONNELL\2104189 USACE-NYD JB MDL Confinement Facility\11_REPORTS\2022-01-21 Geotech Rpt\BMcD- USACE JB-MDL Containment Facility Geotech Rpt.docx

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Executive Summary

GEI Consultants, Inc. (GEI) prepared this report to present the results of a subsurface exploration program and foundation recommendations for the proposed confinement facility at the Joint Base McGuire-Dix-Lakehurst military complex in Burlington County, New Jersey. We performed these services in general accordance with the Uniform Facilities Criteria (UFC) DOD Building Code (UFC 1-200-01) (Building Code), which is an adaptation of the 2018 International Building Code, as well as in general accordance with UFC for Geotechnical Engineering (UFC 3-220-01).

The geotechnical exploration program consisted of 4 test pits excavated to 7 to 11 feet below the ground surface, 4 geotechnical test borings advanced up to about 32 feet below the ground surface. Subsurface conditions encountered in the explorations were generally medium dense sand deposits with up to 40 percent low plasticity to nonplastic fines.

Stabilized groundwater levels were observed in existing on-site monitoring wells between

9.9 and 10.1 feet below ground surface. An approximate 3-foot-thick very stiff sandy silt layer was observed at about 26 feet below grade in one test boring and 1.5 feet of sandy clay was observed in one of the test pits at 9.3 feet below grade.

Groundwater was encountered in two of the test pits at depths between 9.3 and 11 feet below the ground surface. Four constant head permeability tests were performed at the design elevations estimated for proposed stormwater basins at the site.

We recommend an allowable bearing capacity of 2 tons/ft2 for spread footings bearing on the native sand layer at least 3 feet below the finished ground surface. This allowable bearing pressure is applicable for footings at least 3 feet wide.

We recommend using Site Class D (Stiff Soil Profile) for seismic design purposes, in accordance with Building Code Section 1613.2.2. Based on site-specific triggering analyses we performed, we found that less than 6 percent of the standard penetration tests (SPTs) data performed below the groundwater table indicate soils are potentially susceptible to liquefaction. In our professional opinion, liquefaction is not a creditable geologic hazard at the site.

The preponderance of data indicates that catastrophic loss of soil strength due to liquefaction would not occur. We do not believe that special protective or mitigative measures are warranted for seismically-induced settlements.

Based on the site geology, topography, and subsurface investigation, it is our opinion that the proposed building is not susceptible to damage from slope instability, lateral spreading, or surface rupture due to faulting.

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1. Introduction

GEI Consultants, Inc. prepared this report to present the results of a subsurface exploration program and foundation recommendations for the proposed building construction in Burlington County, New Jersey (Fig. 1). We understand the U.S. Army Corps of Engineers- New York District (USACE-NYD) is proposing to construct a single-story 8 Bed Level 1 Confinement Facility with additional parking lot and stormwater management features in the grassed area on the southwest corner of W. Tuskegee Airman and Vandenburg Avenues.

Burns & McDonnell Engineering Company, Inc. (BMcD) engaged GEI to provide geotechnical engineering services for this project. Oversight and technical direction for this project on behalf of USACE-NYD was provided by BMcD.

1.1 Scope of Services

GEI completed the following scope of services for this report. These services were performed to investigate the subsurface conditions at the Site:

Reviewed site plans and preliminary building layout drawings.

Performed exploration mark outs at the site for the New Jersey One Call utility mark out request.

Prepared a site-specific Health and Safety Plan (HASP).

Engaged a subcontractor to assist in the performance of a subsurface exploration program consisting of geotechnical test borings, test pits, and in situ permeability tests.

Evaluated soil samples recovered from the exploration program and prepared test pit and test boring logs as well as water level readings from observation wells previously installed by others.

Engaged a geotechnical testing laboratory and an analytical laboratory to perform testing on soil samples from the test borings.

Developed recommendations for site development.

Evaluated the data obtained and prepared this Geotechnical Report.

We performed these services in the general accordance with the Uniform Facilities Criteria (UFC) DOD Building Code (UFC 1-200-01) (Building Code), which is an adaptation of the 2018 International Building Code, as well as in general accordance with UFC Geotechnical Engineering (UFC 3-220-01).

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1.2 Authorization

Our work was performed in general accordance with our proposal dated October 7, 2021 and Standard Purchase Order number 190063,0 dated November 5, 2021.

1.3 GEI Team

The following GEI personnel performed the services for this report:

Sean T. DiBartolo, P.E. Project Manager / Senior Geotechnical Engineer

Joseph G. Engels, P.E. In-House Reviewer

Jeanne A. LeFebvre, P.E. (MA) Senior Geotechnical Engineer

Jordan Passno Staff Professional (Field Representative)

1.4 Elevation Datum and Horizontal Coordinate System

Elevations provided in this report are in feet and are referenced to the North American Vertical Datum of 1988 (NAVD88). Horizontal coordinates (northing and easting) are U.S.

State Plane coordinates in U.S. survey feet and are referenced to the North American Datum of 1983 (NAD83), New Jersey State Plane.

1.5 Site and Project Description

The area proposed for development is on the McGuire-Dix-Lakehurst joint base, in a grassed area north of Building 2301 (military police station). The site is bound by W. Tuskegee Airman Avenue on the north and Vandenburg Avenue to the east. An asphalt parking abuts the proposed building area, between W. Tuskegee Airman Avenue.

We understand that USACE is proposing to construct a single-story, 8-Bed, Level 1 Confinement Facility north of the existing police station. The proposed development will include an additional asphalt parking lot area. Existing stormwater management features are located to the east and south of the proposed expansion area.

Existing site grades within the proposed development generally range between El. 110 and El. 116 across the site but is relatively level at EL. 116. Site grade decreases in elevation to EL. 110.5 at the existing stormwater features to the east and southwest of proposed development.

We have assumed that the building will be slab-on-grade with conventional shallow foundations.

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2. Subsurface Explorations

2.1 Subsurface Explorations

GEI visited the site to lay out the testing locations on November 4, 2021 in preparation for the New Jersey One Call utility mark out service. All test locations were staked out in the field based on the proposed site improvements. Explorations were documented in the field by measuring them from staked locations set previously be GEI using a Leica Viva GNSS GS14 receiver (SmartPole). Ground surface elevations at the explorations were estimated using the SmartPole unit.

All test locations were cleared by hand before any intrusive activity began.

GEI field representatives were on site on November 19 and November 22, 2021 to coordinate and log explorations, obtain soil samples, and perform infiltration tests. Soil was visually classified in the field using GEI’s visual manual soil description guide, which is based on the Unified Soil Classification System (USCS) ASTM D2487. The test pit logs, test boring logs, and GEI’s visual-manual soil description guide are included in Appendix A.

Approximate exploration locations are shown in Fig. 2. A summary of the exploration program is provided in Table 1.

2.1.1 Test Pits

GEI subcontracted AmeriDrill, Inc. of Levittown, Pennsylvania (AmeriDrill), excavated four test pits, TP1 to TP4, on November 22, 2021. The test pits were excavated using a Case 580 Super M Backhoe with an approximate 11-foot reach. Grab samples were generally collected from any change within the soil strata encountered then visually inspected and classified. TP1, TP3, and TP4 were terminated at 11 feet below ground surface. TP2 was terminated at 7 feet due to maximum reach and access constraints on an inclined slope. The test pits were backfilled with the excavated soil and tamped in lifts with the backhoe bucket.

2.1.2 Geotechnical Test Borings

AmeriDrill, under subcontract to GEI, drilled four geotechnical test borings at the site on November 19, 2021, using a CME 55LCX track-mounted drilling rig. The borings were advanced to depths ranging from 22 to 32 feet using hollow-stem auger drilling techniques.

Test borings were located within or near proposed building locations and new pavement areas.

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All test borings were cleared to 4 feet using hand tools, prior to any sampling. Standard Penetration Testing (SPT) and split-spoon sampling were generally performed at 4 feet, 10 feet and at 5-foot intervals thereafter using an automatic hammer. Representative samples of the soils obtained by the sampler were classified by the on-site GEI Field Inspector. The samples were placed in appropriately identified sealed glass jars and transported to our Bloomfield, New Jersey office for storage and laboratory assignment.

Soil samples were observed for saturation during drilling and depth to groundwater was measured from existing observation wells located near the proposed development area.

Existing observation wells were installed by others at an unknown date. All boreholes were backfilled drill spoils and tamped with backhoe bucket upon completion.

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3. Subsurface Conditions

3.1 Geologic Setting

The site generally consists of colluvial and alluvial deposits from Pleistocene period, that consist of primarily sand to clayey sand with minor silt and sand according to a desktop review of local surficial geologic maps.

3.2 Subsurface Conditions

The generalized subsurface conditions at the site are described below, in order of increasing depth. The soil conditions are known only at the exploration location and are summarized in Table 1.

Two generalized soil layers were encountered in the explorations we performed and are described below, starting at the ground surface.

The drilling contractor used an automatic hammer to perform the SPTs to measure the N-values in the field (termed Nm), which resulted in a variation in the efficiency of delivering the theoretical energy of a 140-pound weight freefalling 30 inches. To use the data set in design, the Nm values were normalized to 60 percent of the theoretical energy delivered in the SPT (termed N60), assuming that the automatic hammer was conservatively 80 percent efficient. The corrected “design” N-values are provided in Table 2.

Recommended values of soil properties and design parameters are presented in Table 3.

The properties were estimated using data from correlations with SPT N60-values, laboratory testing results, published empirical correlations, and our engineering judgement.

Conditions between exploration locations may vary significantly from the descriptions given below.

Topsoil – Explorations in grassed areas encountered dark brown to brown silty sand of topsoil. These soils can be further characterized as a fibrous “rootmat” about 6 inches thick over sands in all borings and test pits.

Sand – We observed fine to medium sand with varying amounts of fines for the entire subsurface profile. The light brown to brown to white sand layer contained up to 15 percent gravel and up to 15 percent silty fines. A layer of gray to light gray silty sand with up to 60 percent sand and silty sand with over 25 percent nonplastic fines was encountered in B1, B2, and TP1 through TP4 between 2 and 5 feet thick, but generally about 3.5 feet thick. In TP3 and TP4 perched water was observed at the bottom of the silty sand.

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Black clayey or silty sand with between 25 to 40 percent to low plasticity fines was encountered in all borings and test pits and was encountered at 12 to 15 feet below ground surface. Varves of medium to coarse black sand with nonplastic fines were observed in B3 and B4. An approximate 3-foot-thick very stiff sandy silt layer was observed at about 26 feet below grade in B2 and 1.5 feet of sandy clay was observed in TP3 at 9.3 feet below grade.

SPT N60-values recorded in the sand deposit were between 4 and 36 blows per foot, but generally ranged between 11 and 28, and averaged 18 blows per foot, indicating medium dense soil conditions.

3.3 Groundwater Conditions

We measured stabilized groundwater levels in existing monitoring wells onsite, installed by others, between November 19 and 22, 2021, at depths between 9.9 and 10.1 feet below the ground surface (El. 106.6 and El. 106.4). Significantly different groundwater levels may occur at other times and locations. Groundwater was encountered in test pits TP3 and TP4 at depths between 9 to 11 feet below the ground surface.

Groundwater levels are subject to seasonal and weather-related variations. Groundwater measurements made at different times and different locations may be significantly different than the measurements taken as part of this investigation.

3.4 In-situ Permeability Testing

We performed constant head permeability tests at the TP1 through TP4 locations using an Aardvark Permeameter in general accordance with ASTM D5126 and manufacture recommendations at excavated depths above and below the silt/silty sand confining layer.

The in-situ permeability tests were performed at the proposed location of the stormwater detention basin. The test zones were excavated and prepared for testing using hand-held augers and brushes in the vadose zone. The test data and calculations are provided in Appendix C with the results summarized in Table 4, which are presented as field-saturated hydraulic conductivity (kfs) and field-saturated infiltration rate (IR) estimates.

We estimated geometric means for the kfs and the IR on soil tested below the silt/silty sand confining layer to be 2.9 x 10-3 cm/s and 4.5 inches/hr. We did not apply a factor of safety to the test results.

Additionally, we performed grain size distribution tests on samples collected within the permeability test zones. The results are summarized in Table 5 and included in Appendix C.

Results from the grain size and hydrometer testing were used to corroborate the observed

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GEI Consultants, Inc. 7 permeability of the soil from the constant head tests, see USDA Soil Texture section below.

The designer of stormwater management systems should apply an appropriate factor of safety against the field-saturated hydraulic conductivity (kfs) and field-saturated infiltration rate estimates presented. Soil infiltration rates from in-situ tests can vary significantly from one location to another due to the heterogeneous characteristics inherent to most soil profiles.

3.5 USDA Soil Texture, NRCS Hydrologic Soil Group, and

Infiltration Rate

As a secondary check of infiltration capacity to compare to the results from the in-situ permeability testing, we evaluated U. S. Department of Agriculture (USDA) soil textures by plotting the grain size analysis results on the USDA Soil Texture Triangle (Fig. 3). The soil texture class for the samples are “Sand,” “Loamy Sand,” and “Sandy Loam.”

We then evaluated the NRCS hydrologic soil groups and infiltration rates using Table 2 from Rawls (1982) and Table 7-1 of the NRCS Part 630 Hydrology National Engineering Handbook. The NRCS hydrologic soil group and infiltration rate for “Sand” is “A” and

8.27 inches/hour, for “Loamy Sand” is “A” and 2.41 inches/hour, and for “Sandy Loam” is “B” and 1.02 inches hour, respectively. NRCS data is summarized in Table 5.

3.6 Laboratory Testing

3.6.1 Geotechnical Testing

TerraSense, LLC of Totowa, New Jersey, under subcontract to GEI, performed the following tests on soil samples obtained from the test boring to confirm field classifications and to estimate engineering properties:

Four (4) grain size analyses with hydrometer readings (ASTM D4913 & D7928)

One (1) California bearing ratio test (ASTM D1883)

Two (2) AWWA (American Water Works Association) Corrosion Suites

Results of the laboratory tests are attached as Appendix D to this report and have been incorporated into the soil descriptions on the boring and test pit logs in Appendix A.

California Bearing Ratio (CBR) testing was performed on a composite from grab samples collected from 1 to 2 feet in TP-1 and TP-4. This composite was re-compacted in the laboratory using the Modified Proctor maximum dry density (estimated maximum dry density of 123.5lb/ft3 based on the relative density and soil classification). CBR test results ranged from 13.1 percent at 0.1-inch penetration and 16.0 percent at 0.2-inch penetration.

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3.6.2 Corrosivity Indicators Testing

TerraSense Laboratory of Totowa, New Jersey, under subcontract to GEI, performed chemical testing to evaluate the corrosivity potential of site soils from composite sample C2 (5 to 12 feet) in B1and composite sample C3 (2 to 12 feet) in B2. The soil sample was tested for Chloride (AASHTO T291), Sulfate (AASHTO T290), and Sulfide (ASTM D4658). The analytical report from Testing Engineers International is provided in Appendix D. Test results are presented in Table 6 and are further discussed in Section 4.6.

TerraSense, LLC of Totowa, New Jersey, under subcontract to GEI performed electrical resistivity (ASTM G57), pH (ASTM G51), and oxidation and reduction potentials (AWWA Appendix A procedures), to help evaluate the corrosivity potential of site soils. The test was performed on composite soil samples, C2 and C3, described above. TerraSense laboratory test results are included in Appendix B. Test results are presented in Table 6 and are further discussed in Section 4.6.

3.7 Sample Storage and Disposition

All soil samples collected as a result of our explorations are being stored at our office in Bloomfield, New Jersey. The soil samples will be held for 30 days after issuance of this report. We will coordinate with your office and arrange to have the samples transported to a long-term storage location or discarded.

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4. Geotechnical Recommendations

The following sections of this report present the recommendations for the design of the subgrade and foundations for the proposed confinement facility.

4.1 Foundation Design

The proposed structure may be supported on shallow foundations bearing on a proof-compacted subgrade consisting of native soils similar to the native sand stratum noted in Section 3.2 or Structural Fill.

The recommended maximum allowable bearing pressure for the design of footings assuming a factor of safety of 3 is:

Bearing Stratum Maximum Allowable

Bearing Pressure Native Sand or Structural Fill Extending to

Native Sand 2.0 tons/ft2

Exterior footings should bear at least 36 inches below the adjacent exterior grade for frost protection. Interior footings should be founded at least 18 inches below the bottom of the floor slab. The tops of all footings should be at least 6 inches below the bottom of the overlying floor slab. This allowable bearing pressure is applicable for footings at least 3 feet wide.

For resistance against lateral forces, we recommend using an ultimate value of 0.35 for coefficient of sliding friction on sand layers and 0.50 on Structural Fill. A factor of safety of at least 1.5 should be applied to the sliding resistance.

We estimate the total settlement of the proposed facility expansion will be less than 1 inch, and differential settlements between adjacent columns will be less than ½ inch. This estimate assumes that the foundations are designed and constructed in accordance with the recommendations in this report. Most of the estimated settlements will occur during construction.

4.2 Floor Slab Design

The slab-on-grade should bear on at least 6 inches of compacted Crushed Stone or Structural Fill. For design of slabs with a Crushed Stone base, a modulus of subgrade reaction of k=200 lb/in3 is recommended for design. We recommend a modulus of subgrade reaction of

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GEI Consultants, Inc. 10 k=100 lb/in3 where the Structural Fill thickness is 12 inches or less and k=200 lb/in3 where the Structural Fill thickness is more than 12 inches. These recommendations are based on the design criteria provided in “Slab Thickness for Industrial Concrete Floors on Grade” by the Portland Cement Association.

We recommend that contraction joints be incorporated between the slab-on-grade and the columns and perimeter walls of the proposed building to accommodate minor differential settlement.

To limit moisture infiltration into finished spaces, a 10-mil minimum thickness polyethylene vapor retarder should be placed beneath all moisture sensitive floor slabs. The vapor retarder should be sealed at the foundation walls, columns, and utility penetrations, and panels should be overlapped and joints sealed.

4.3 Wall Design

All earth retaining structures used on the project should be designed using the following design parameters:

Parameter Value Total Unit Weight of Granular Backfill () 125 lb/ft3

Angle of Internal Friction (ϕ) 32°

Cohesion (c) 0 lb/ft2

At-Rest Earth Pressure Coefficient, (Ko) 0.47(1)

Active Earth Pressure Coefficient, (Ka) 0.31(1)

Passive Earth Pressure Coefficient, (Kp) 3.0(1)

Allowable coefficient of friction between rough concrete footing and granular bearing soil 0.50(1)

(1) = Ultimate values, with no Factor of Safety applied

Below-grade walls that are restrained from movement by a rigid element should be designed for at-rest earth pressures. Retaining walls free to rotate at the top should be designed for active earth pressures. Fig. 4 depicts the recommend lateral earth pressure envelopes for design of walls for either at-rest or active earth pressures. Sliding of concrete walls and grade beams may be resisted by passive earth pressures in front of the foundation element using the passive earth pressures shown in Fig. 5. The minimum factor of safety against overturning and sliding is 2.0 (1.5 if passive pressures are ignored) and should be reduced to

1.1 when earthquake loads are included in the evaluation.

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In addition to the lateral loads exerted by the soil against the walls, allowance should be included for lateral stresses imposed by any temporary or long-term surcharge loads, such as cars or trucks adjacent to the walls or adjacent footing loads.

The recommended wall design parameters do not consider the development of hydrostatic pressure behind the walls. As such, positive wall drainage must be provided for all earth retaining structures. These drainage systems can be constructed of open-graded washed stone isolated from the soil backfill with a geosynthetic filter fabric and drained by perforated pipe, or several wall drainage products made specifically for this application. Where backfill soils are not drained using an appropriately-designed drainage system, the lateral soil pressure on proposed retaining walls must consider hydrostatic forces and submerged soil unit weight.

The earth pressures given in the above table assume placement and compaction of the backfill in accordance with recommendations elsewhere in this report. Compact backfill directly behind walls with light, hand-operated compactors. Heavy compactors and grading equipment should not be allowed to operate within 10 feet of the walls during backfilling to avoid developing excessive temporary or long-term lateral soil pressures.

We anticipate that geosynthetic reinforced retaining wall systems would be the most cost-effective systems to be used at the site. The vendors of these types of retaining wall systems will generally design and warrantee the walls and provide the geosynthetic and wall facing materials.

The soil parameters used in the design of the walls should be based on tests performed on the actual soil and geosynthetic materials that will be used to construct the walls.

4.4 Seismic Design and Liquefaction

4.4.1 Seismic Design Parameters

We recommend using Site Class D for seismic design purposes, in accordance with Building Code Section 1613.2.2, based on the soil profile encountered at the site. Corresponding spectral response design parameters are as follows:

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Building Code Seismic Design Values Site Class D

Risk Category III SS 0.194 g S1 0.049 g Fa 1.6 Fv 2.4

SDS 0.207 g SD1 0.079 g

PGAM 0.174 g Seismic Design Category B

Peak ground acceleration (PGAM) has been adjusted for Site Class effects, per ASCE 7-16 Section 11.8.3.

Based on a Site Class D and Risk Category II for the proposed expansion, and in accordance with Building Code Tables 1613.2.5(1) and (2), Seismic Design Category B should be assigned to site structures.

4.4.2 Liquefaction Triggering Analysis

We evaluated the potential for liquefaction (development of seismically-induced porewater pressures in soil) using the SPT N60-values from the test borings and a site-specific procedure, in accordance with Building Code Section 1803.5.12. The procedures described in Boulanger and Idriss (2014), which supersedes NCEER-97-0022, and MSHA (2009) were used for the evaluation, along with the following input parameters:

Design Earthquake magnitude (Mw) = 5.64 [Mean deaggregated hazard]

Peak ground acceleration adjusted for site class effects (PGAM) = 0.174 g

Based on these methodologies, if the safety factor against pore-pressure-increase in a zone is greater than 1.4, then it may be assumed that the earthquake shaking will not be strong enough to trigger strength loss in that zone. If the safety factor in a zone is less than 1.0, then triggering of strength loss is assumed. For safety factors between 1.0 and 1.4, triggering of strength loss is considered possible. Based on the UFC 3-220-01 for Risk Category III structures, an acceptable factor of safety associated with liquefaction potential is 1.1.

4.4.2.1 Triggering Analysis using SPT Data

Our evaluation indicates that a factor of safety against seismically-induced liquefaction was less than 1.0 for 1 of the 17 SPTs (6 percent) performed below the groundwater table and between 1.0 and 1.4 for 2 of the 17 SPTs (12 percent) performed below the groundwater

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GEI Consultants, Inc. 13 table. Fig. 6 plots the analyzed SPT data as a factor of safety against liquefaction below the water table at various elevations. Based on the SPT liquefaction triggering analysis there appears to be limited risk associated with liquefaction.

4.4.2.2 Recommendations

While the preponderance of data indicates that catastrophic loss of soil strength due to liquefaction would not occur, there may be some damage to the building due to settlement in the event of an earthquake of the magnitude assumed in the analyses. We expect the new structure will remain functional, at least temporarily, after settlements on the scale noted above, which generally would not correspond with outright soil failure. Therefore, we do not believe that special protective or mitigative measures are warranted for seismic-induced settlements.

Based on the site geology, topography, and subsurface investigation, it is our opinion that the proposed building is not susceptible to damage from slope instability, lateral spreading, or surface rupture due to faulting.

4.5 Frost Depth

We recommend using a frost depth of 36 inches below final grade for the site.

4.6 Soil Corrosivity

Electrical resistivity is a broad indicator of soil corrosivity because corrosion reactions are electrochemical in nature and proceed most rapidly when resistivity (i.e., resistance to the flow of ions and electrical current) is low. Specifically, resistivity is a measure of how strongly a given material opposes the flow of electrical current. The composite samples C2 and C3 had electrical resistivity readings between of 7,700 and 13,400 Ω-cm at a saturated soil condition, indicating a slightly corrosive to mildly corrosive environment.

Sulfates in soil and groundwater in concentrations greater than 1,000 mg/kg are generally considered to be corrosive to structural elements. The American Concrete Institute recommends that Type II cement be used if sulfate concentrations exceed 1,000 mg/kg or 1,000 ppm. Sample test results indicate sulfates at a concentration of <10 ppm.

Chloride concentrations above 500 mg/kg or 500 ppm are generally considered to be corrosive to structural elements. Sample test results indicate sulfates at a concentration between 15 and 18 ppm.

We summarized our evaluation of the soil corrosivity to structural elements shown in the table below by comparing the laboratory test results to some available corrosivity references.

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Test Laboratory

Results Reference

Corrosivity to Structural

Elements pH 7.6 to 8.3 Caltrans - Corrosion Guidelines

January 2015 Not corrosive

Electrical Resistivity

7,700 to 13,400 Ω-cm

EPRI - Environmental Factors Governing Corrosion Rates, Report 1021854

December 2011

Slightly to Mildly

Corrosive

Chloride 15 to 18 ppm Caltrans - Corrosion Guidelines January 2015 Not corrosive

Sulfate <10 ppm Caltrans - Corrosion Guidelines January 2015 Not corrosive

Concrete for foundation elements is being placed in areas where salt or other deicing compounds may be used in the winter. Due to the possible presence of soluble salts or other corrosive agents, we recommend concrete made with Type II cement be specified for below ground concrete.

4.7 Pavement Design

Pavement thicknesses should be designed in accordance with the New Jersey Department of Transportation (NJDOT) Standard Specifications. Our recommendations below are not based on site-specific traffic information and are only estimates based on local experience.

A California Bearing Ratio (CBR) test was performed on a composite soil sample to evaluate the strength of the existing near-surface site soils as a subbase material for a pavement section and is included in Appendix B. Based on the testing, the sample had CBR values of

13.1 percent at 0.1 inch and 16.0 percent at 0.2 inch. We estimate that the modulus of subgrade reaction (k) for this composite sample is approximately 200 lb/in2/in based on Huang (2004).

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4.7.1 Flexible Pavements

We recommend the following minimum flexible pavement design sections for standard-duty (parking areas) and heavy-duty (WB-67 trucks) traffic loading conditions:

Layer Material

Standard-Duty Flexible

Pavement

Heavy-Duty Flexible

Pavement Bituminous Surface

Course NJDOT Superpave

HMA 12.5M64 2.0 inches 2.0 inches

Bituminous Binder Course

NJDOT Superpave HMA 19M64 2.0 inches 3.0 inches

Base Course NJDOT Dense

Graded Aggregate 6.0 inches 12.0 inches

The bituminous concrete binder course should be placed and compacted with the specified thicknesses described above in accordance with the NJDOT Standard Specifications.

A tack coat should be applied to the binder surface and the vertical face at the perimeter of the patch in accordance with NJDOT Standard Specifications prior to placement of bituminous concrete surface course with the specified thickness described above.

The bituminous concrete surface course with the specified thicknesses described above should be placed and compacted in accordance with the NJDOT Standard Specifications.

4.7.2 Rigid Pavements

Concrete pavement sections may be used to resist heavy loads and turning forces in areas such as dock approaches, fire lanes, or trash enclosures. We recommend the following minimum rigid pavement design sections for heavy-duty (WB-67 trucks) traffic loading conditions:

Layer Material Heavy-Duty Rigid

Pavement

4,000-lb/in2

Jointed Concrete

NJDOT 903.03

Portland Cement

Concrete

8.0 inches

Base Course NJDOT Dense

Graded Aggregate 8.0 inches

We recommend that rigid pavements be designed in general accordance with the most recent edition of American Concrete Institute (ACI) Guide 330R. An adequate number of smooth steel dowels should be provided at all expansion and contraction joints. All dowels should be coated and lubricated and affixed with metal or plastic caps. The size and spacing of dowels

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We recommend implementing a preventative maintenance program to include such items as crack and joint sealing/patching and localized full-depth repairs (as necessary) to enhance future performance and prolong the design life of the pavement.

4.8 Karst Potential and Expansive Conditions

Based on our experience in the area, there is no karst potential in the bedrock geology at the site nor do we expect the soils at this Site to be expansive, dispersive, or have a collapsing nature.

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5. Construction Considerations

5.1 Subgrade Preparation

5.1.1 Removal of Surface Materials

Site preparation should include the removal of all unsuitable surface materials within the footprint of the proposed building. This includes concrete, asphalt and graded aggregate base course, and any unstable surface or subsurface soils.

5.1.2 Removal/Re-routing of Utilities

Existing buried utilities within the footprint of the proposed building should be removed and replaced with compacted Structural Fill, or they should be filled with flowable fill (Controlled Low Strength Material) and capped if left in place. Unplugged or uncapped pipes that are left in place may serve as conduits for subsurface erosion which can result in the formation of voids below foundations or floor slabs. Where existing utilities are left in place and plugged in the building footprint, it may be necessary to undercut poorly compacted backfill to provide adequate support for footings or slabs. Existing utilities that are to remain in use should be rerouted around the proposed building footprint.

5.1.3 Foundations

Footings should bear on a subgrade consisting of native sand. Bearing surfaces should be free of standing water, frost, and loose soil before placement of reinforcing steel and concrete. Subgrade soils that require undercutting should be replaced with Crushed Stone underlain by geotextile.

The final excavation to the footing subgrade should be made using a smooth-bladed excavator bucket, to avoid disturbing or loosening the soil and compacted with at least three coverages of a vibratory compactor weighing at least 200 pounds and imparting an impact load of at least 2.5 tons.

5.1.4 Slabs-on-Grade

The existing native sands are suitable for support of a slab-on-grade. After cut and fill placement operations are completed to achieve subgrade elevation for the building pad, the exposed surface should be proof-rolled under the supervision of the geotechnical engineer with a 10-ton vibratory roller. Subgrades that become unstable (i.e., soft, yielding, rutting, pumping, etc.) under the action of -proofrolling may require selective undercutting or further stabilization prior to placement of the Structural Fill or Crushed Stone base.

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5.2 Excavation Support and Dewatering

Excavations will be in soil, and conventional excavation with a backhoe appears feasible.

All excavations should be made in accordance with OSHA standards and the Building Code pertaining to the protection of property and worker safety. Any excavation greater than 4 feet in depth should be inclined for safety unless shoring is used. We anticipate that open cut excavations in conformance with OSHA safety requirements will be feasible for the majority of excavations for this project.

Perched groundwater may be encountered during the footing excavations. The specifications should require the contractor to maintain the groundwater level below the bottom of the excavation at all times. We recommend that each footing excavation be sloped slightly to a sump. We anticipate that filtered sumps will be adequate to control groundwater during construction, if necessary.

Sumps should be located outside the limits of the footings and should extend at least 2 feet below the bottom of the excavation. The sump should consist of a perforated pipe wrapped in filter fabric and surrounded by Pea Stone. Dewatering effluent should be fed to recharge pits located away from the site excavations.

5.3 Freezing Conditions

The soils at the site are susceptible to frost heave. Therefore, if construction is performed during freezing weather, special precautions will be required to prevent the subgrade soils from freezing. Freezing of the soil beneath the foundation during construction may result in subsequent settlement of the structure.

All subgrades should be free of frost before placement of concrete. Frost-susceptible soils that have frozen should be removed and replaced with compacted Structural Fill. The footing and the soil adjacent to the footing should be insulated until they are backfilled. Soil placed as fill should be free of frost, as should the ground on which it is placed.

If slabs-on-grade or footings are built and left exposed during the winter, precautions should be taken to prevent freezing of the underlying soil.

5.4 Backfilling and Compaction

Soils to be used as fill imported from off-site sources should also meet the attached gradation requirements. Fill placed within the building limits, within a 3-foot-wide zone outside foundation walls, and under pavements should meet the compaction requirements for Structural Fill. Backfill placed in non-structural areas should meet the compaction requirements for Ordinary Fill.

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5.5 Site Disturbance

Project specifications should require the contractor to maintain stable site conditions at all times. Specific measures to stabilize equipment traffic areas could include compacted aggregate placed over a geotextile, temporary drainage, or other appropriate measures.

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6. Limitations

This report was prepared for exclusive use of Burns & McDonnell and the design team. Our recommendations are based on the project information provided to us at the time of this report and may require modification if there are any changes in the nature, design, or location of the proposed building. We cannot accept responsibility for designs based on our recommendations unless we are engaged to review the final plans and specifications to determine whether any changes in the project affect the validity of our recommendations, and whether our recommendations have been properly implemented in the design.

The recommendations in this report are based in part on the data obtained from the subsurface explorations. The nature and extent of variations between explorations may not become evident until construction. If variations from the anticipated conditions are encountered, it may be necessary to revise the recommendations in this report. We recommend that GEI be engaged to make site visits during construction to check that the subsurface conditions exposed during construction are in general conformance with our design assumptions and ascertain that the work is being performed in compliance with the contract documents.

Our professional services for this project have been performed in accordance with generally accepted engineering practices. No warranty, expressed or implied, is made.

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7. References

American Concrete Institute (ACI) (2008). “Guide for the Design and Construction of Concrete Parking Lots Guide.” ACI 330-08, Farmington Hills, Michigan.

American Society for Testing and Materials (2022). Annual Book of ASTM Standards, Volume 04.08, Soil and Rock; ASTM, West Conshohocken, Pennsylvania.

Boulanger, R.W. and I.M. Idriss (2014). “CPT and SPT Based Liquefaction Triggering Procedures.” Report No. UCD/CGM-14/01.

Huang, Y.H. (2004). Pavement Analysis and Design. 2nd Edition. Prentice Hall.

Idriss, I.M. and R.W. Boulanger (2008). “Soil Liquefaction during Earthquakes.”

Monograph MNO-12. Earthquake Engineering Research Institute, Oakland, California.

Mine Safety and Health Administration (MSHA) (2009). Engineering and Design Manual, Coal Refuse Disposal Facilities, Second Edition. Mine Safety and Health Administration, United States Department of Labor, MSHA, May, Revised August 2010.

National Center for Earthquake Engineering Research (NCEER) (1997). Proceedings of the NCEER Workshop on Evaluation of Liquefaction Resistance of Soils, T. L.

Youd and I. M. Idriss, editors, Technical Report NCEER-97-022, NCEER, NY.

New Jersey Department of Transportation (2019). Updated Standard Specifications for Road and Bridge Construction. Trenton, New Jersey.

Newell, Wayne L., Powars, D.S., Owens, J.P., Stanford, S.D., & Stone, B.D. (2000).

“Surficial Geologic Map of Central and Southern New Jersey.” U.S. Geological Survey Miscellaneous Investigations Series Map I-2540-D, scale of 1:100,000.

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Recommended Material Specifications

Structural Fill and Ordinary Fill shall consist of hard, durable sand and gravel, free of clay, organic matter, surface coatings, and other deleterious materials. Soil finer than the No. 200 sieve (the “fines”) should be nonplastic. On-site material can be re-used as Structural Fill or Ordinary Fill, provided they can meet the appropriate gradation and compaction requirements indicated below and do not contain deleterious materials. Soils to be used as fill imported from off site should also meet the gradation requirements given below.

Structural Fill

Structural Fill shall meet the following gradation requirements:

Sieve Size Percent Passing by

Weight 3 inches 100

0.5 inch 50 to 100

No. 4 35 to 85

No. 16 20 to 65

No. 50 5 to 40

No. 200 (fines) 0 to 8

Structural Fill shall be compacted in maximum 9-inch-thick, loose lifts to at least 95 percent of the maximum dry density determined in accordance with ASTM D1557 (Modified AASHTO Compaction). The moisture content should be held to within ±3 percent of optimum moisture content (as determined by ASTM D1557).

Ordinary Fill

Ordinary Fill shall meet the following gradation requirements:

Sieve Size Percent Passing by

Weight 6 inches 100

3 inches 80 to 100

No. 4 20 to 100

No. 200 (fines) 0 to 20

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Ordinary Fill shall be compacted in maximum 12-inch-thick, loose lifts to at least 92 percent of the maximum dry density determined in accordance with ASTM D1557 (Modified AASHTO Compaction). The moisture content should be held to within ±3 percent of optimum moisture content (as determined by ASTM D1557).

Dense Graded Aggregate

Dense Graded Aggregate (DGA) shall conform to the requirements of the New Jersey Department of Transportation Standard Specifications for Aggregates in Section 901.10.

DGA shall meet the following gradation requirements:

Sieve Size Percent Passing by

Weight

1.5 inches 100

0.75 inch 55 to 90

No. 4 25 to 50

No. 50 5 to 20

No. 200 (fines) 3 to 10

DGA shall be compacted in maximum 9-inch-thick, loose lifts to at least 95 percent of the maximum dry density determined in accordance with ASTM D 1557 (Modified AASHTO Compaction). The moisture content should be held to within ±3 percent of optimum moisture content (as determined by ASTM D 1557).

Crushed Stone

Crushed Stone shall consist of clean, durable, sharp-angled fragments of gravel free from surface coatings and shall conform to the requirements of the New Jersey Department of Transportation Standard Specifications for Aggregates in Section 901.03, Table 901.03-1, No. 5. Materials that break up when alternatively frozen and thawed or wetted and dried shall not be used. Crushed Stone shall meet the following gradation requirements or approved equal:

Sieve Size Percent Passing by Weight

1.5 inches 100

1 inch 90 to 100

0.75 inch 20 to 55

0.5 inch 0 to 10

0.375 inch 0 to 5

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Crushed Stone should be compacted with at least four passes of a vibratory compactor.

Pea Stone

Pea Stone shall be screened gravel conforming to the requirements of ASTM D 448 for stone size No. 8 and shall consist of durable, inert rounded stone, free from loam or clay, surface coatings, and deleterious materials. Pea Stone shall meet the following gradation requirements:

Sieve Size Percent Passing by Weight

0.5 inch 100

0.375 inch 85 to 100

No. 4 10 to 30

No. 8 0 to 10

No. 16 0 to 5

Controlled Low Strength Material

Controlled Low Strength Material (CLSM) shall conform to the requirements of the New Jersey Department of Transportation Standard Specifications for Aggregates in Section 903.09.

Geotextile

Geotextile should be a non-woven fabric, consisting of Mirafi 140N or an approved equal product.

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Tables

Table 1. Subsurface Exploration Data

USACE-NYD JB MDL Confinement Facility

Fort Dix, Burlington County, New Jersey

Depth Elev. Depth Elev.

B1 437,047 466,312 116.1 32.0 84.1 0.0 116.1 0.5 115.6

B2 437,040 466,223 116.8 32.0 84.8 0.0 116.8 0.5 116.3

B3 437,067 466,089 115.9 27.0 88.9 0.0 115.9 0.5 115.4

B4 437,147 465,942 116.3 22.0 94.3 0.0 116.3 0.5 115.8

TP1 437,113 466,180 116.4 11.0 105.4 0.0 116.4 0.6 115.8

TP2 437,062 466,389 111.1 7.0 104.1 -- -- 0.5 110.6

TP3 436,968 466,094 111.4 11.0 100.4 -- -- 1.0 110.4

TP4…