P197_1620400 SIGN RFP_Parts 6 (2 of 11).pdf

Geotechnical Site Characterization Report December 6, 2019

NAVFAC Mid-Atlantic

P-197 – F-35 Aircraft Maintenance Hangar and Parking Facility

DO: N4008519F4488

MCAS Cherry Point, North Carolina

P-197 F-35 Aircraft Maintenance Hangar and Parking Facility Geotechnical Site Characterization Report

December 6, 2019 NAVFAC Mid-Atlantic

030788

REPORT VERIFICATION

PROJECT NAME: Geotechnical Site Characterization Report REVISION No.: 1

This is to certify that I, Paul Zhang, P.E., have reviewed the attached document and have satisfied myself the work performed was conducted in conformance with generally accepted industry practice under my authority. The attached seal is only applicable to the original of the referenced document.

Professional Engineer Seal:

Signature: _______________

Name: Paul Zhang, P.E.

P.E. No.: 030788

Date: December 6, 2019

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Executive Summary This geotechnical Site Characterization Report documents the work completed for Naval Facilities Engineering Command (NAVFAC) Mid-Atlantic Project P-197 F-35 Aircraft Maintenance Hangar and Parking Facility that will be located at the intersection of “A” Street and 6th Avenue within the Marine Corps Air Station (MCAS) at Cherry Point, North Carolina. The site is an active MCAS, with buildings, paved vehicle acesss drives and streets, paved parking lots, paved airfield, grassed and partially landscaped areas. The project site is located within an area of Land Use Controls (LUC) due to existing contaminated soil and groundwater conditions.

This project consists of contructing a new F-35 Maintenance Hangar (P-197), 1,700 vehicle parking garage, and aircraft wash rack, and associated transportation, site, and airfield improvements. Finished floor for the maintenance hangar and parking garage are expected to be at El. 27.5. As the project site is currently developed, the project also includes demolishion of existing buildings and miscellaneous supporting structures prior to construction.

HDR Engineering, Inc. (HDR) conducted a subsurface exploration program at the project site consisting of nineteen Standard Penetration Test (SPT) borings, Shelby tube samples of cohesive soils and six Cone Penetration Test with dynamic pore pressure measurement (CPTu) soundings, of which two were Seiscimic CPTu (SCPTu) soundings. Additional investigations included completion of field infiltration tests and collection of California Bearing Ratio (CBR) samples.

Laboratory testing on selected samples recovered from the exploration included natural moisture content, grain size analyses, Atterberg Limits, Standard Proctor and CBR, 1-D consolidation, and chemical-analytical testing for the characterization of the Investigation Derived Waste (IDW).

Surficial and near surficial conditions generally consist of concrete and asphalt pavements and uncontrolled fill up to an approximate maximum thickness of five feet. Loose to medium dense sand soils, occasionally interbedded with clay, were typically encountered to depths up to 35 feet below existing grade, but as deep as 45 feet within the existing airfield area.

Underlying the loose to medium dense sand, explorations encountered soft to stiff clay and loose sand. This stratum exists between the depth of approximately 35 and 55 feet below existing grade in the vicinity of the two planned major structures, where as it was encountered from approximately 50 feet and 65 feet within the existing areafield area. The bearing stratum for potential deep foundation elements is comprised of medium dense to very dense sand soils, typically encountered below depths of 55 feet within the areas of the maintenance hangar and parking garage. Groundwater was generally encountered between depths of 7 to 13 feet.

Lightly loaded structures, such as at the wash rack, may be supported on shallow spread footings bearing in suitable natural subgrade or controlled structural fill. More heavily loaded structures, such as the maintenance hangar and the parking garage, will likely require a deep foundation system to carry design loads while maintaining acceptable settlements. As the area is identified as a LUC, excavations should be limited to reduce the risk of encountering contaminated materials and deep foundation systems must be evaluated relative to impacts associated with penetrating the aquifer confinement layers.

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Contents

Executive Summary ....................................................................................................................................... i

1 Introduction

1.1 Background

1.2 Objective and Scope

2 Geology

2.1 Regional Geology

2.2 Site Geology

3 Field Services

3.1 Subsurface Exploration Program

3.2 Infiltration Rate Testing

4 Laboratory Testing

5 Summary of Subsurface Conditions

5.1 Interpreted Stratigraphy of Airfield Pavement Area

5.2 Interpreted Stratigraphy of Maintenance Hangar

5.3 Interpreted Stratigraphy of Parking Garage

5.4 Groundwater Observations

6 Subsurface Characterization

6.1 Soil Index Properties

6.2 Shear Strength and Compressibility

6.3 Bulk Samples Test Results

7 Geotechnical Site Characterization Findings and Evaluations

7.1 Foundation Considerations

7.2 Subgrade Preparation

7.3 Groundwater and Land Use Controls

7.4 Earthwork

8 Limitations

9 References

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Tables

Table 3-1: Subsurface Exploration Information Table 4-1: Summary of Laboratory Testing Program Table 6-1: Summary of In-Situ Soil Conditions Table 6-2: Estimated Geotechnical Parameters Table 6-3: Summary of Bulk Sample Laboratory Testing

Appendices Appendix A: Figures and Table Appendix B: Subsurface Exploration Logs and Data Appendix C: Laboratory Test Results

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P-197 F-35 Aircraft Maintenance Hangar and Parking Garage

NAVFAC MidAtlantic

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1 Introduction

1.1 Background

HDR Engineering, Inc. (HDR) is pleased to submit this Geotechnical Site Characterization Report to Naval Facilities Engineering Command (NAVFAC) Mid-Atlantic Project P-197 F-35 Aircraft Maintenance Hangar and Parking Facility that will be located at the intersection of “A” Street and 6th Avenue within the Marine Corps Air Station (MCAS) at Cherry Point, North Carolina. HDR’s work was completed in accordance with delivery order (N4008519F4488) executed on January 4, 2019.

The project site is currently an active MCAS with buildings, paved vehicle acess drives and streets, paved parking lots, a paved airfield, grassy and partially landscaped areas. The area of proposed improvement at the project site is generally flat, with elevations ranging from 25 feet to 28 feet. A site vicinity map is provided on Figure A-1 in Appendix A.

The project will consist of a new F-35 Maintenance Hangar (P-197), 1,700 vehicle parking garage (5-levels), aircraft wash rack, and associated transportation, site, and airfield improvements. The P-197 hangar will be approximately 665 feet long by 187 feet wide and will be constructed along the northeastern side of 6th Avenue. An aircraft wash rack will also be constructed to the northwest of the hangar. The parking garage will be constructed across 6th Avenue. New driveways and vehicle access improvements will be constructed around the hangar and parking garage, as well as new concrete sidewalks for pedestrian access. The project will also include demolition of five existing buildings and miscellaneous supporting structures. The proposed improvements are depicted on Figure A-2 in Appendix A.

1.2 Objective and Scope

The objective of HDR’s geotechnical evaluation is to characterize subsurface conditions at the project site and provide geotechnical data to support the PDA of the P-197 F-35 Aircraft Maintenance Hangar and Parking Facility project. To achieve this objective, HDR executed the following general scope of services:

Reviewed existing subsurface exploration data in the vicinity of the proposed facility, which was provided by NAVFAC Planned and executed a subsurface exploration program consisting of 19 SPT borings, five Shelby tubes collection, five infiltration tests, three hand augers for CBR sample collection, four CPTu soundings and two SCPTu soundings

Collected one composite soil sample and one composite fluid sample for chemical-analytical testing

Assigned laboratory testing on selected soil samples from the explorations to aid in classification and estimation of geotechnical engineering parameters

Prepared this report summarizing the results of the exploration program and HDR’s geotechnical characterization of the subsurface soils.

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2 Geology

2.1 Regional Geology

The project site is located within the Coastal Plain Physiographic Province of North Carolina.

The Coastal Plain is characterized by poorly to well-sorted unconsolidated marine to fluvial sediments, varying from clay to gravel with lateral variation in thickness. These sediments generally increase in thickness towards the east. Vertical variation within the geologic formations of the Coastal Plain is often controlled by cyclic transgression and regression depositional sequences that coarsen with depth. Coastal Plain is characterized by flat land to gently rolling hills and valleys. Elevations range from sea level near the coast to about 600 feet in the Sandhills of the southern Inner Coastal Plain.

2.2 Site Geology

Locally, the project site is underlain by the Yorktown and Duplin Formations, Undivided. The Duplin formation exists mainly in areas south of Neuse River where the project site is located.

The Duplin formation is described as bluish-gray unconsolidated sands, arenaceous clays, shell marls, and limestone representing the latest phase of Miocene deposition in the region. Some of the Duplin beds in southern North Carolina are less glauconitic and more uniformly coarse-grained than the equivalent members of the Yorktown Formation to the north. In regions where Duplin strata are observed, Miocene–aged deposits are not recognized, and wherever the basal beds are exposed, the formation is seen to rest unconformably on Cretaceous or Eocene-aged strata, which may consist of phosphatic basal conglomerate.

3 Field Services

3.1 Subsurface Exploration Program

NAVFAC provided HDR with three geotechnical engineering data reports including the “P-228 ATC Tower and Air Operations Facility” dated September 21, 2018, the “P-199 Aircraft Maintenance Hangar and Paraloft” dated August 28, 2017 and the “P-235 Flightline Utility Modernization” dated September 21, 2018. The existing exploration data that are at or in the near vicinity of the project site are shown on Figure A-2 in Appendix A and the logs associated with the referenced historic explorations are included in Appendix B.

The borings from P-199 project is not in the near vicinity of the project site and have not included in this Site Characterization Report. HDR’s review of the referenced historic subsurface information resulted in the conclusion that depicted conditions are consistent with those encountered by the current exploration program. As part of the historic data review and evaluation, HDR also evaluated historic topographics maps, aerial photographs and geologic maps, and did not observe surface or subsurface characterisitics substantially different than those reported herein.

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HDR planned and executed a subsurface exploration program to collect subsurface data at the project site. GET Solutions, Inc. (GET) of Virginia Beach, Virginia drilled a total of nineteen standard penetration test (SPT) borings, three hand auger locations for CBR sample collection, and performed five infiltration tests. The SPT borings were advanced to depths ranging from 12 feet to 75 feet using hollow stem auger and mud rotary drilling techniques. Standard Penetration Tests with split-spoon sampling of soils were conducted in accordance with ASTM International (ASTM) testing method D1586 using an automatic hammer with an efficiency of approximate 84%.

Twenty-four-inch long SPT samples were collected in the upper 10 to 12 feet of each borehole (with continuous SPT sampling) and at five-foot intervals below a depth of 10 feet or 12 feet to boring termination. Bulk samples were collected at the three CBR sample locations. A total of five Shelby tubes were collected at depths between 35 feet and 50 feet in borings 19B-004, 19B- 011 and 19B-013, with one Shelby tube collected at a depth of 2 feet in boring 19B-013.

Piezometers were installed to a depth of 12 feet in borings 19BMP-001 through 19BMP-005 and infiltration testing was performed in the immediate vicinity of the five BMP borings.

All explorations were backfilled with a bentonite/cement mix from the bottom upon completion.

BMP-series borings were backfilled with grout after 48 hour water readings. Borings were drilled through the concrete surface, except in boring 19B-013, and were patched with concrete patch on the surface after grout backfill.

S&ME, Inc. (S&ME) personnel advanced four cone penetrometer test (CPTu) and two seismic cone penetrometer (SCPTu) soundings to depths between 67 feet and 75 feet below ground surface using a 16-ton track mounted CPTu rig. The six soundings were terminated prior to 100 feet due to the maximum reaction force encountered from the underlying dense material. A 20-ton compression type cone penetrometer with a 15-cm2 tip area and a 225-cm2 friction sleeve area was used for the CPTu soundings. The cone is designed with an equal end area friction sleeve and a net end area ratio of 0.80. CPTu testing is performed in general accordance with the current ASTM D5778 industry standards.

The field investigations were conducted between September 9 and October 1, 2019. Specific exploration locations for the project site are shown on Figure A-2 in Appendix A, and are summarized in Table 3-1.

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Table 3-1: Subsurface Exploration Information

Subsurface Exploration

Type of Exploration

Exploration Location with respect to proposed facility/features

Depth (ft)

As-Built Survey Location

Remarks Northing1

(US

Survey- ft)

Easting1

(US

Survey- ft)

Ground Surface

Elevation2

(NAVD88)

(ft)

19B-001 SPT Airfield 75.0 426981 2633108 27 --

19B-002 SPT Airfield 75.0 426655 2633175 26 --

19B-003 SPT Airfield 75.0 426649 2632905 27 --

19B-004 SPT Maintenance Hangar 74.6 426493 2632398 28 Shelby Tube collected at 45 to 47 ft.

19B-005 SPT Maintenance Hangar 75.0 426461 2632609 28 --

19B-006 SPT Maintenance Hangar 75.0 425997 2633039 27 --

19B-007 SPT Maintenance Hangar 75.0 426275 2632433 28 --

19B-008 SPT Maintenance Hangar 73.0 426062 2632647 26 --

19B-009 SPT Maintenance Hangar 73.2 425848 2632892 26 --

19B-010 SPT Parking Garage 73.1 425807 2632683 25 --

19B-011 SPT Parking Garage 68.1 425836 2632322 27 Shelby Tube collected at 41 to 43 ft.

19B-012 SPT Parking Garage 67.6 425622 2632507 25 --

19B-013 SPT Parking Garage 73.9 425650 2632146 25 Shelby Tube collected at 2 to 4 ft, 35 to 37 ft and 50 to 52 ft.

19B-014 SPT Parking Garage 73.2 425436 2632331 25 --

19BMP-001 SPT Airfield 12.0 426499 2632668 28 Infiltration Testing3, Piezometer Installed3

19BMP-002 SPT Airfield 12.0 426286 2632942 26 Infiltration Testing3, Piezometer Installed3

19BMP-003 SPT Airfield 12.0 426259 2633363 24 Infiltration Testing3, Piezometer Installed3

19BMP-004 SPT Maintenance Hangar 12.0 426203 2632464 27 Infiltration Testing3, Piezometer Installed3

19BMP-005 SPT Parking Garage 12.0 425883 2632701 25 Infiltration Testing3, Piezometer Installed3

19CPT-001 CPTu Maintenance Hangar 67.9 426356 2632525 28 --

19CPT-002 CPTu Maintenance Hangar 79.4 426262 2632808 27 --

19CPT-003 CPTu Parking Garage 67.3 426046 2632500 25 --

19CPT-004 CPTu Parking Garage 69.6 425844 2632522 27 --

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Subsurface Exploration

Type of Exploration

Exploration Location with respect to proposed facility/features

Depth (ft)

As-Built Survey Location

Remarks Northing1

(US

Survey- ft)

Easting1

(US

Survey- ft)

Ground Surface

Elevation2

(NAVD88)

(ft)

19SCPT-001 SCPTu Maintenance Hangar 69.8 425934 2633010 27 --

19SCPT-002 SCPTu Parking Garage 69.7 425706 2632273 26 --

19CBR-001

CBR Sample

Locations Vicinity of Parking

Garage

2.8 425587 2632342 28 Bulk sample collected

19CBR-002 2.0 425948 2632405 25 Bulk sample collected

19CBR-003 2.8 425637 2632162 25 Bulk sample collected 1The Nothings and Eastings are based on North American Datum (NAD) 1983 State Plane North Carolina FIPS 3200.

2 The ground surface elevations are estimated from surveyed topographic information and should be considered accurate to within approximately 1 foot. NAVD88 = North American Vertical Datum 1988).

3Infiltration Testing was performed in the immediate vicinity of the boring location at a depth of 3.5 feet to 6 feet below the ground surface. Piezometer was installed to a total depth of 12 feet in the boring to measure 48-hour water reading.

Prior to drilling operations, GET laid out exploration locations in the field for utility clearance by others. As the project site is located within an area of Land Use Controls (LUC) due to existing contaminated soil and groundwater conditions, GET prepared and submitted a work plan to the MCAS Cherry Point Environmental Affairs Department (EAD) for regulatory approval prior to performing the field exploration for this project. The work plan review required EPA and NCDEQ approval that was coordinated through EAD. A condition of the work plan was that all investigation derived waste (IDW), consisting of both soil and water, be containerized and characterized for disposal at an MCAS facility.

GET staff monitored the drilling in the field, which included visual-manual classification of soil samples, preparation of field exploration logs, monitoring conformance with drilling and sampling criteria, and observation of general site conditions. Pocket penetrometer tests were typically performed on cohesive soil samples at the time of sample collection. The results of the pocket penetrometer tests are shown on the exploration logs provided in Appendix B. Disturbed samples were stored in glass jars and undisturbed samples were collected and stored in thin-walled steel sampling tubes (Shelby Tubes).

As-drilled exploration locations and surface elevations are approximate and were not instrument-surveyed. Surface elevations at the exploration locations were interpreted by HDR using a topographic map and are referenced to the North American Vertical Datum (NAVD) 88. The boring locations are shown on Figure A-2 in Appendix A.

Boring logs and subsurface exploration reports are provided in Appendix B.

3.2 Infiltration Rate Testing

Infiltration rate testing was performed by GET on September 19, September 20 and October 9, 2019. The test was performed in the immediate vicinity of each of the five BMP-series borings (19BMP-001 through 19BMP-005) at a depth of 3.5 feet to 6 feet below the ground surface. The infiltration test was based on constant head borehole permeator test and Glover Solution was the

Page | 6 analytical method used to calculate the infiltration rates. The infiltration rates ranged from 0.001 to 0.307 inches per hour. Test results are included in Appendix B.

4 Laboratory Testing GET performed laboratory testing on soil samples collected from the subsurface explorations.

HDR personnel evaluated the field exploration logs and assigned specific samples for testing.

Testing was performed to aid in the classification of representative soils encountered in the borings and to support development of geotechnical engineering parameters for design. Table 4-1 summarizes the laboratory testing completed for this project.

Table 4-1: Summary of Laboratory Testing Program

Laboratory Test Test Specification Number of Tests

Moisture Content ASTM D 2216 52

Grain Size Analysis ASTM D 6913 39

Atterberg Limits ASTM D 4318 28

Standard Proctor ASTM D 698 3

California Bearing Ratio (CBR) ASTM D 1883 3

Shelby Tube Extrusion and Logging -- 5

Consolidation Test ASTM D 2435 4

TCLP 8 RCRA Metals, Oil and Grease and TPH-DRO & GRO

-- 2 (1 for Soil Sample and 1 for Water Sample)

Specifically related to the IDW characterization required for disposal, soil samples were collected from each of 24 drums containing the soil cuttings. The collected soil samples were blended to form one composite soil sample representative of the drummed soil cuttings. Similarly, representative samples of decontamination fluid were collected from five drums containing water on-site and a composite sample of the drummed fluids was collected.

The submitted cuttings composite sample did not produce concentrations of the analytes above the laboratory’s method detection limits. The submitted fluids composite sample produced a TPH- DRO concentration of 3 milligrams/Liter. The remainder of the analytes were not detected above the laboratory’s method detection limits. Based upon the analytical results, the drummed liquid and solid Investigative Derived Waste was considered not hazardous from a disposal perspective.

The results of the laboratory testing are provided in Appendix C.

5 Summary of Subsurface Conditions Table A-1 in Appendix A provides a summary of the explorations performed including exploration number, type and depth, surface material type and thickness, the different strata

Page | 7 encountered in each boring, and groundwater observation depths. Figures A-5 though A-7 in Appendix A depict subsurface profiles.

5.1 Interpreted Stratigraphy of Airfield Pavement Area

The following subsurface strata were observed in the subsurface explorations performed within Airfield Pavement Area. The subsurface explorations that were performed for this facility are presented in Table 3-1 above. The subsurface fence diagram indicating the interpreted stratigraphy of Airfield Pavement Area is in Figure A-5 of Appendix A.

Concrete – Borings performed for this facility encountered 9.5 to 13.5 inches of concrete on the surface. Boring 19BMP-003 also encountered 6 inches of soil cement under the concrete surface.

Uncontrolled Fill – Uncontrolled Fill was encountered in two test borings (19B-001 and 19B-002) below the pavement surface with an approximate thickness of 1 foot. The uncontrolled fill consisted of sand with varying amounts of silt and clay and was tan, reddish-tan and gray in color.

Upper Sand (Stratum 1) – Loose to medium dense sand with varying amounts of silt and clay (SP, SP-SM, SM, SC, SP-SC) was encountered at approximate El. 23 to 26. The corrected N-value for hammer efficeincy (N60) ranged from 4 to 31 blows per foot (bpf) with an average of 15 bpf. The sand was typically tan, gray, brown, dark brown and red-brown in color. Firm to stiff clay (CL, CH) with an approximate thickness of 2 feet was also encountered within Stratum 1 in three borings (19B-001, 19B-003, and 19BMP-001) at approximate top elevations of El. 23 and El. 19. The N60 of these fine grained soils ranged from 6 to 13 bpf, with an average of 9 bpf. Stratum 1 soils are gray, brown, dark brown and red-brown in color.

Clay (Stratum 2A) – Stratum 2A was not encountered in Airfield Pavement area.

Intermediate Sand (Stratum 2B) - Stratum 2B was encountered below Stratum 1 at approximate El. -20. The stratum consists of medium dense sand with varying amounts of silt and clay (SM, SP-SM, SP-SC, SC). N60 ranged from 10 to 18 bpf with an average of 12 bpf. Stratum 2B soils are gray, dark gray, tan and brown in color.

Lower Sand (Stratum 3) –Stratum 3 was encountered below Stratum 2B at El. -35. The stratum consists of medium dense to dense sand with varying amounts of silt and clay (SP-SC, SP-SM, SM, SC). N60 ranged from 13 to 28 bpf with an average of 19 bpf. Stratum 3 soils are gray, dark gray and brown in color.

5.2 Interpreted Stratigraphy of Maintenance Hangar

The following subsurface strata was observed in the subsurface explorations performed in Maintenance Hangar. The subsurface explorations that were performed for this facility are

Page | 8 presented in Table 3-1 above. The subsurface fence diagram indicating the interpreted stratigraphy of Maintenance Hangar is in Figure A-6 of Appendix A.

Concrete – Four borings (19B-004 thorugh 19B-007) performed for this facility encountered 9.0 to 13.0 inches of concrete and two borings (19B-008 and 19B-009) encountered 2.5 to 6 inches of asphalt underlain by 4 to 6 inches of aggregate subbase.

Uncontrolled Fill – Uncontrolled Fill was encountered in three test borings (19B-004, 19B- 006 and 19B-009) below the pavement surface with an approximate thickness of 3 to 5 feet at top elevations between El. 25 and 27. The uncontrolled fill consisted of sand with varying amounts of silt and clay. N60 ranged from 16 to 34, with an average of 20 bpf; the fill soils are tan, red-tan, dark gray and black in color.

clay (SP, SP-SM, SM, SC) was encountered at El. 22 to 28. The corrected N-value for hammer efficeincy (N60) ranged from 4 to 48 blows per foot (bpf) with an average of 16 bpf. The sand was typically brown, gray, red-tan and tan in color. Soft to stiff clay (CL) with thickness of 2 feet was also encountered within Stratum 1 in three borings (19B-005, 19B- 007 and 19B-008) at shallow depths between top elevations of El. 22 and El. 24. The N60 of these fine grained soils ranged from 4 to 10 bpf, with an average of 7 bpf. Stratum 1 soils are gray in color.

Clay (Stratum 2A) – Stratum 2A was encountered in eight of nine explorations (except in boring 19B-008) at El. -10 to -25. The stratum consists of soft to stiff clay with varying plasticity (CH, CL). N60 ranged from 4 to 10 bpf with an average of 7 bpf. Stratum 2A soils are gray and dark gray in color.

Intermediate Sand (Stratum 2B) - Stratum 2B was encountered in six of nine explorations (except in borings 19B-004, 19B-005 and 19B-009) at El. -9 to -12. The stratum consists of loose sand with varying amounts of silt and clay (SM, SP-SM, SC). N60 ranged from 7 to 10 bpf with an average of 8 bpf. Stratum 2B soils are gray and dark gray in color.

Lower Sand (Stratum 3) –Stratum 3 was encountered below Stratum 2A/2B at El. -24 to -31. The stratum consists of medium dense to very dense sand with varying amounts of silt and clay (SP, SP-SM, SM, SC). N60 ranged from 11 to >50 bpf with an average of 33 bpf. Stratum 3 soils are tan, brown, gray and dark gray in color.

5.3 Interpreted Stratigraphy of Parking Garage

The following subsurface strata was observed in the subsurface explorations performed in Parking Garage. The subsurface explorations that were performed for this facility are presented in Table 3-1 above. The subsurface fence diagram indicating the interpreted stratigraphy of Parking Garage is in Figure A-7 of Appendix A.

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Surficial Soil – Surficial soil was encountered in one test boring (19B-013) with an approximate thickness of 0.5 feet.

Concrete – Five borings performed on this facility (19B-010, 19B-011, 19B-012, 19B-014 and 19BMP-005) encountered 4.0 to 9.0 inches of concrete on the surface.

Uncontrolled Fill – Uncontrolled Fill was encountered in three test borings (19B-011, 19B- 012 and 19B-013) below pavement/surficial soil with an approximate thickness of 2 to 5 feet ranging at top elevations between El. 25 and 26. The uncontrolled fill consisted of loose to medium dense sand with varying amounts of silt and clay. N60 ranged from 7 to 10, with an average of 8 bpf. Fill soils are dark gray, tan and brown in color.

clay (SP, SP-SM, SM, SC) was encountered at El. 21 to 27. The corrected N-value for hammer efficeincy (N60) ranged from 4 to 24 blows per foot (bpf) with an average of 12 bpf. Soft to stiff clay (CL) with approximate thickness of 3 to 4 feet was also encountered within Stratum 1 in two borings (19B-010, 19B-014) below concrete surface. The N60 of these fine grained soils ranged from 3 to 10 bpf, with an average of 7 bpf. Stratum 1 soils are gray, tan, and red-tan in color.

Clay (Stratum 2A) – Stratum 2A was encountered in eight explorations at El. -12 to -17.

The stratum consists of very soft to stiff clay with varying plasticity (CH, CL). N60 ranged from 0 to 10 bpf with an average of 6 bpf. Stratum 2A soils are gray and dark gray in color.

Intermediate Sand (Stratum 2B) - Stratum 2B was encountered in six of eight explorations (except in borings 19B-012 and 19B-014) at El. -7 to -12. The stratum consists of very loose to loose sand with varying amounts of silt and clay (SP, SC). N60 ranged from 3 to 6 bpf with an average of 4 bpf. Stratum 2B soils are gray and dark gray in color.

Lower Sand (Stratum 3) –Stratum 3 was encountered below Stratum 2A/2B at El. -25 to -37. The stratum consists of medium dense to very dense sand with varying amounts of silt and clay (SP, SP-SM, SM, SC). N60 ranged from 10 to >50 bpf with an average of 41 bpf. Stratum 3 soils are tan, brown, gray and dark gray in color.

5.4 Groundwater Observations

Subsurface water levels were measured in the test borings at the time of drilling. Water was introduced into the boreholes as part of the drilling process used to advance the borings, which could impact water level measurements or make it harder to visually observe the transition to depths below water during drilling. A temporary piezometer was installed in BMP-series borings 19BMP-001 through 19BMP-005 and post drilling (48-hr) subsurface water measurements were made at four BMP borings. The 48-hr subsurface water measurement attempt on 19BMP-005 was not successful due to the clogging of the well pipe with saturated soils with no standing water present within the well pipe.

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The groundwater depths during drilling ranged from 8 feet to 13 feet and the 48-hr water readings in the BMP borings ranged from 7 feet to 9 feet. The estimated Seasonal High Water Table (SHWT) depths has been estimated to coincide with the generally observed water levels in the borings based on color transitions in the soils in proximity to the observed levels. The estimated SHWT depths ranged from 6 feet to 10 feet. The estimated SHWT depths and the subsurface water depths are also summarized in Table A-1 and presented in the boring logs provided in Appendix B of this report.

Note, subsurface water levels may fluctuate due to precipitation, season, temperature, site grading, drilling methods, and other factors that may be different from those prevailing at the time HDR completed its subsurface investigation.

6 Subsurface Characterization

6.1 Soil Index Properties

Table 6-1 summarizes the index properties of soils encountered at this project site. Refer to figure A-8 in appendix A for graphical summary of index properties.

Table 6-1: Summary of In-Situ Soil Conditions

Stratum1 Approximate Elevation (ft)

Index Test Results

Range of

LL (%)

Range of

PI (%)

Range of w (%) Range of LI

Range of Fines

Content (%)

Upper Sand (Stratum 1) 27.5 to -10 NP to 71 NP to 49 8 to 53 0.06 to 1.6 3 to 45

Clay (Stratum 2A) -10 to -30 53 to 89 33 to 67 30 to 70 0.46 to 0.75 63 to 87

Intermediate Sand (Stratum 2B)2 -10 to -30 35 to 50 15 to 23 31 to 45 0.18 to 1.6 19 to 50

Lower Sand (Stratum 3)2 Below -30 -- -- -- -- --

Note(s):

NP=Non-Plastic 1Refer to table A-1 in appendix A for approximate stratum thickness and location.

2Stratum 2B are sands with percentage of fines (clay) between 41 to 50% as indicated by lab test results performed within this stratum.

3No lab tests performed on soil sample from stratum 3.

6.2 Shear Strength and Compressibility

Soil parameters for the different subsurface layers were estimated based on the subsurface information collected in the SPT borings and CPTu soundings. HDR evaluated the undrained strength of fine-grained cohesive soils using results from CPTu data using relationship developed from Terzaghi bearing capacity theory consisting of corrected tip resistance (qt), total vertical stress (σv), and cone factor (Nkt). A cone factor of 17 was used. An interpreted profile for

Page | 11 undrained strength for Stratum 2A is shown in figure A-9 in appendix A, the results are summarized in Table 6-2 below.

For coarse-grained cohesionless soils, the friction angles were estimated based on correlations with SPT N-values (blow counts) in the borings and correlations with normalized cone tip resistance (Qtn) from the CPTu soundings. For fine-grained cohesive soils, the friction angle was estimated based on correlation adapted from Terzaghi el al. (1996) with plasticity index. An interpreted profile for friction angle for the different strata is shown in figure A-10 in appendix A, the results are summarized in Table 6-2 below. The correlations with SPT N-values in Figure 33 of Center for Geotechnical Practice and Research publication (CGPR), Performance and Use of the Standard Penetration Test in Geotechnical Engineering Practice were considered when estimating the friction angle of the cohesionless soils. The correlation with Qtn developed by Kulhawy and Mayne (1990) was used when estimating the friction angle from the CPTu sounding.

HDR estimated compressibility parameters for Stratum 2A based on the results of the four 1- Dimensional consolidation tests completed on recovered samples from 19B-004, 19B-0011 and 19B-013. Coarse-grained soil compressibility was based on SPT correlations developed by Tan et al. (1991). Table 6-2 summarizes the strength and compressibility parameters HDR interpreted based on the collected field and laboratory test data.

Table 6-2: Estimated Geotechnical Parameters

Soil Type Avg.

N60

Total Unit

Weight (pcf)

Drained Friction Angle

(degrees)

Undrained Cohesion (psf)

Young’s Modulus

(tsf) CR RR P’c (tsf) OCR

Upper Sand (Stratum 1) 7 115

30 (Top of Stratum to El 15), 34 (El 15 to El -10)

--- 95 to 195 0.02 --- --- --

Clay (Stratum 2A) 7 110 29

Top of Stratum at 1200 psf and linearly increasing with depth at 80 psf / ft

-- 0.38 0.02 3.3 2.1

Intermediate Sand

(Stratum 2B) 6 120 30 --- -- 0.2 to 0.42 0.01 to

0.02 2.8 to 5.9 2 to 3.7

Lower Sand (Stratum 3)

33 120 32 --- 200 to 300 0.01 --- --- --

Notes: CR = Compression Ratio; RR = Recompression Ratio; P’c = Preconsolidation Pressure

The values presented in Table 6-2 represent HDR’s interpretation of field and laboratory test results and may not be appropriate for use in all design cases. The geotechnical engineer of record is responsible for the appropriate interpretation and application of parameters to support their design.

6.3 Bulk Samples Test Results

Table 6-3 below shows summary of laboratory test results of bulk samples.

Page | 12

Table 6-3: Summary of Bulk Sample Laboratory Testing

Boring USCS % Fines

Natural MC

Optimum MC

Maximum Dry Density (pcf)

CBR

(molded density/moisture) Swell

19CBR-001 SC 30.2 10.6 10.6 122.6 5.0 (116.6/12.7) 0.1%

19CBR-002 SM 17.6 7.5 10.3 118.5 10.0 (112.8/12.3) 0%

19CBR-003 SC 33.5 12.1 10.9 116.3 6.3 (110.8/13.0) 0.8%

7 Geotechnical Site Characterization Findings and Evaluations

The general stratigraphic conditions across the project site included a loose to medium dense upper sand (Stratum 1) to approximately El. -10 to -15 feet, underlain by by soft to stiff clays (Stratum 2A) and loose intermediate sands (Stratum 2B) underlain by medium dense to very dense sands (Stratum 3). Stratum 2A thickness ranges from approximately 10 to 20 feet in Parking Garage and 5 to 15 feet in Maintenance Hangar location. Stratum 2A was not encountered in Airfield Pavement area.

Stratum 2B thickness is approximately 5 to 10 feet in Parking Garage Location and 10 to 20 feet in Maintanance Hangar and Airfield location. Medium dense to very dense sands were encountered below Stratum 2A/2B to the boring termination depths. Loose to medium dense Uncontrolled Fill consisting of sand was encountered below pavement surface/surficial soil in eight test borings and the thickness ranged from 1 to 5 feet. The following sections provide guidance to potential design-build teams pertaining to geotechnical conditions that may impact project approach and design.

7.1 Foundation Considerations

Shallow spread foundations bearing on controlled structural fill or prepared natural subgrades may be suitable for support of lighly loaded structures, such as the wash rack. More heavily loaded structures, such as the maintenance hangar and the parking garage, will likely require deep foundation support to control settlement and transfer design loads to the deeper Stratum 3 bearing layer. Considering this, deep foundations are considered a viable option to support vertical compressive (columns and walls) foundation loads for the two major structures. Dynamic and/or static load testing is required to verify design capacities and the appropriate capacity contributions of each soil strata encountered.

7.2 Subgrade Preparation

All subgrades underlying the pavements, floor slabs and/or shallow spread foundations shall be constructed of at least 24 inches of select material underlain by a woven geotextile fabric (AASHTO M288 Class 1 woven geotextile, elongation < 50%, with seams overlapped a minimum of 24") intended for subgrade stabilization. Materials excavated mau be suitable for reuse as

Page | 13 controlled fill at other locations of the site provided they are re-used at depths greater than than 24 inches below the planned subgrade and meet project requirements.

7.3 Groundwater and Land Use Controls

Groundwater was encountered in the B-series explorations as shallow as seven feet and as deep as thirteen feet below existing ground surface. Although encountered water levels were typically below El. 20, perched conditions can occur, with water being encountered as shallow as within a few feet of the ground surface. Dewatering may be required to construct subsurface project elements, and will likely be comprised of shallow sumps with pumping, as well as a well-point system for maintaining a deeper drawdown during excavation. Discharge of all pumped water shall be routed away from all on-going work and prepared subgrades. Discharge shall comply with all necessary environmental permits.

As the project is located in an area of Land Use Controls due to existing contaminated soil and groundwater conditions design-build teams must clearly understand the permitting implications and restrictions to design and construction activities. The potential for contamination exists and design solutions should favor those limiting the amount of spoil generation. Agencies involved in review of permit applications will include the MCAS Cherry Point Environmental Affairs Department, the Environmental Protection Agency, and the North Carolina Department of Environmental Quality. Potential limitations to the selection of a deep foundation system may include restrictions on penetrating the aquifer confinement layers.

7.4 Earthwork

Surficial soil was encountered in only one test boring up to approximately six inches. All test borings encountered mostly concrete with asphalt underlain by aggregate subbase in two locations. HDR recommends Design-Build teams consider the impacts of stripping during subgrade preparation, in addition to the thickness of the surficial soils, uncontrolled fill, asphalt and concrete presence.

Additionally, the project also includes demolition of five existing buildings and miscellaneous supporting structures. All excavation subgrades from demolition activity must be inspected and approved by the Contractor's Geotechnical Engineer prior to constructing backfill and fill.

Demolished structures should not impede the performance of the newly constructed facility.

Earthwork can likely be completed using conventional earth moving equipment as neither rock nor dense materials were encountered within the expected cut depths required for site grading.

The soft/loose soils or uncontrolled fill may require recompaction or overexcavation and replacement with suitable fill if, after final grading, these soils remain near the planned finished subgrade elevations.

8 Limitations HDR is not the Geotechnical Engineer of Record for overall site design. These borings explorations were advanced only for the purposes of gathering subsurface data and to be used

Page | 14 for further analysis. The geotechnical engineering recommendations presented herein are based on the geotechnical engineer’s experience and professional opinion. These services were performed with the degree of skill and care normally utilized by other members of the geotechnical engineering profession practicing in this location and at this time. There is no warranty, either express or implied.

The information contained herein is directed at, and intended to be utilized within our contracted scope of work. This report is not intended to be used for any other purposes.

The considerations presented in this report are based on the subsurface conditions present in the borings and the engineering characteristics of the soil as determined through field and laboratory testing at this point in time.

This report does not reflect variations in subsurface conditions that may exist between or beyond these borings. Variations in soil conditions should be expected between the borings, the nature and extent of which may not become evident except through further investigation or until construction is undertaken. Subsurface conditions can change over time due to both natural and manmade forces, including changes in condition and/or use of adjacent properties.

9 References

1. International Building Code, Chapter 18 Soils and Foundations, 2018.

2. NAVFAC, Soil Mechanics, Design Manual 7.01, 1986.

3. NAVFAC, Foundations and Earth Structures, Design Manual 7.02, 1986.

4. North Carolina Geological Survey, 1985, Geologic Map of North Carolina: North Carolina Geological Survey, General Geologic Map, scale 1:500,000.

5. Unified Facilities Criteria, Structural Engineering, UFC 3-301-01, 2019.

6. Unified Facilities Criteria, Soil Mechanics, UFC 3-220-10N, 2005.

7. Minimum Design Loads for Buildings and Other Structures, ASCE 7-16 Standard.

Appendix A: Figures and Table

- Figure A-1: Site Vicinity Map

- Figure A-2: Subsurface Exploration Plan

- Figure A-3: Site Geology Map

- Figure A-4: Site Soils Map

- Table A-1: Summary of Estimated Subsurface Stratigraphy

- Figure A-5,A-6 and A-7: Subsurface Fence Diagrams

- Figure A-8: Summary of Selected Field Data and Tested Index Properties

- Figure A-9: Profile of Estimated CPTu Sounding Undrained Strength

- Figure A-10: Profile of Estimated Drained Friction Angle

PATH: \\CLTSMAIN\GIS_DATA\GIS\PROJECTS\7315_NAVFACMIDATLANTIC\10147721_P197_F35E_HANGAR_AND_PARKING\7.2_WORK_IN_PROGRESS\MAP_DOCS\MXD\WORKING\FIGURE_A1_SITEVICINITY.MXD - USER: MICHRYAN - DATE: 10/25/2019

O

PROJECT

LOCATION

SITE VICINITY MAP

FIGURE A-1

P-197 F35E HANGAR AND PARKINGSite Location

0 50Miles

O

P-197 F35E

HANGAR AND

PARKING SITE

B-3

B-2

B-1CPT-3

CPT-2

CPT-1

C-4

C-3

C-2

C-1

B-4

B-3

B-2

B-1

CBR-003

CBR-002

CBR-001

19B-014

19B-013 19B-012

19B-011 19B-010

19B-009

19B-008

19B-007

19B-006

19B-005 19B-004

19B-003 19B-002

19B-001

19CPT-004

19CPT-003

19CPT-002

19CPT-001

19BMP-005

19BMP-004

19BMP-003

19BMP-002

19BMP-001

19SCPT-002

19SCPT-001

PATH: \\CLTSMAIN\GIS_DATA\GIS\PROJECTS\7315_NAVFACMIDATLANTIC\10147721_P197_F35E_HANGAR_AND_PARKING\7.2_WORK_IN_PROGRESS\MAP_DOCS\MXD\WORKING\FIGURE_A2_EXPLORATION_LOCATION_PLAN.MXD - USER: MICHRYAN - DATE: 12/5/2019

SUBSURFACE EXPLORATION PLAN

FIGURE A-2

P-197 F35E HANGAR AND PARKING

0 500Feet

OSite Location

LEGEND

!> CPTu Sounding !> BMP Facility Boring !> Structure Boring

!> CBR

!> Seismic CPTu Sounding

!> P-228 Existing Explorations !> P-235 Existing Explorations

Profile A-A'

Profile C-C'

Profile B-B'

Tpy

PATH: \\CLTSMAIN\GIS_DATA\GIS\PROJECTS\7315_NAVFACMIDATLANTIC\10147721_P197_F35E_HANGAR_AND_PARKING\7.2_WORK_IN_PROGRESS\MAP_DOCS\MXD\WORKING\FIGURE_A3_SITE_GEOLOGY_MAP.MXD - USER: MICHRYAN - DATE: 10/31/2019

P-197 F35E HANGAR AND PARKING

FIGURE A-3

SITE GEOLOGY MAP

Site Location

0 500Feet

O

GEOLOGY IN PROJECT AREA

Tpy - Yorktown Formation and Duplin Formation, Undivided. Yorktown Formation: Fossiliferous clay with varying amounts of fine-grained sand, bluish gray, shell material. Duplin Formation:

Shelly, medium-to-coarse grained sand, sandy marl, and limestone, blueish gray; mainly in area south of Neuse River.

Ur

Lc

BrB

BrB BrB

BrB

BrB

BrB

BrB

PATH: \\CLTSMAIN\GIS_DATA\GIS\PROJECTS\7315_NAVFACMIDATLANTIC\10147721_P197_F35E_HANGAR_AND_PARKING\7.2_WORK_IN_PROGRESS\MAP_DOCS\MXD\WORKING\FIGURE_A4_SITE_SOILS_MAP.MXD - USER: MICHRYAN - DATE: 10/28/2019

P-197 F35E HANGAR AND PARKING

FIGURE A-4

SITE SOILS MAP

Site Location

0 500Feet

O

LEGEND

Ur - Urban Land BrB - Bragg Soils Lc - Lynchburg, Urban Land

Craven County, North Carolina

Ur—Urban land

Map Unit Composition Urban land: 90 percent Estimates are based on observations, descriptions, and transects of the mapunit.

Description of Urban Land

Setting Down-slope shape: Linear Across-slope shape: Linear

Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8 Hydric soil rating: No

Data Source Information

Soil Survey Area: Craven County, North Carolina Survey Area Data: Version 22, Sep 16, 2019

Map Unit Description: Urban land---Craven County, North Carolina

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

10/28/2019

TABLE A‐1 ‐ SUMMARY OF ESTIMATED SUBSURFACE STRATIGRAPHY

P‐197, F35 Hangar and Parking Garage MCAS Cherry Point, North Carolina

Geotechnical Data Report October 29, 2019

Exploration Exploration Type Exploration Depth (ft)

Approximate Surface El. (ft)

Concrete (in.)

Soil Cement (in)

Asphalt (in.)

Aggreagate Base (in.)

Surficial Soil (in.)

Top Elevation (ft.)

Stratum Thickness (ft)

Top Elevation (ft.)

Stratum Thickness (ft)

Top Elevation (ft.)

Stratum Thickness (ft)

Top Elevation (ft.)

Stratum Thickness (ft)

Top Elevation (ft.)

Stratum Thickness (ft)

During Drilling (ft) 48 Hours After Drilling (ft)

Seasonal High Water Table (ft)

19B‐001 SPT 75 27 13 ‐‐ ‐‐ ‐‐ ‐‐ 26 1 25 50 N.E. N.E. ‐25 15 ‐40 N.P. 12 ‐‐ 8

19B‐002 SPT 75 26 11 ‐‐ ‐‐ ‐‐ ‐‐ 25 1 24 47 N.E. N.E. ‐23 14 ‐37 N.P. 12 ‐‐ 8

19B‐003 SPT 75 27 14 ‐‐ ‐‐ ‐‐ ‐‐ N.E N.E. 26 50 N.E. N.E. ‐24 11 ‐35 N.P. 8 ‐‐ 6

19B‐004 SPT 75 28 11 ‐‐ ‐‐ ‐‐ ‐‐ 27 5 22 36 ‐14 10 N.E. N.E. ‐24 N.P. 12 ‐‐ 8

19B‐005 SPT 75 28 13 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 27 41 ‐14 15 N.E. N.E. ‐29 N.P. 8 ‐‐ 8

19B‐006 SPT 75 27 12 ‐‐ ‐‐ ‐‐ ‐‐ 26 3 23 33 ‐25 5 ‐10 15 ‐30 N.P. 12 ‐‐ 8

19B‐007 SPT 75 28 9 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 27 36 ‐19 10 ‐9 10 ‐29 N.P. 8 ‐‐ 8

19B‐008 SPT 73 26 ‐‐ ‐‐ 3 6 ‐‐ N.E. N.E. 25 36 N.E. N.E. ‐11 20 ‐31 N.P. 8 ‐‐ 8

19B‐009 SPT 73 26 ‐‐ ‐‐ 6 4 ‐‐ 25 3 22 33 ‐11 15 N.E. N.E. ‐26 N.P. 13 ‐‐ 8

19B‐010 SPT 73 25 4 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 25 36 ‐17 10 ‐12 5 ‐27 N.P. 9 ‐‐ 8

19B‐011 SPT 68 27 8 ‐‐ ‐‐ ‐‐ ‐‐ 26 5 21 31 ‐16 9 ‐10 7 ‐25 N.P. 10 ‐‐ 8

19B‐012 SPT 68 25 4 ‐‐ ‐‐ ‐‐ ‐‐ 25 2 23 35 ‐12 20 N.E. N.E. ‐32 N.P. 12 ‐‐ 8

19B‐013 SPT 74 25 ‐‐ ‐‐ ‐‐ ‐‐ 6 25 4 21 28 ‐13 15 ‐7 6 ‐28 N.P. 8 ‐‐ 8

19B‐014 SPT 73 25 9 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 24 41 ‐17 20 N.E. N.E. ‐37 N.P. 13 ‐‐ 10

19BMP‐01 SPT 12 28 10 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 27 N.P. N.P. N.P. N.P. N.P. N.P. N.P. 8 9 8

19BMP‐02 SPT 12 26 10 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 25 N.P. N.P. N.P. N.P. N.P. N.P. N.P. 9 7 8

19BMP‐03 SPT 12 24 11 6 ‐‐ ‐‐ ‐‐ N.E. N.E. 23 N.P. N.P. N.P. N.P. N.P. N.P. N.P. 8 7 8

19BMP‐04 SPT 12 27 7 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 26 N.P. N.P. N.P. N.P. N.P. N.P. N.P. 8 7 8

19BMP‐05 SPT 12 25 5 ‐‐ ‐‐ ‐‐ ‐‐ N.E. N.E. 25 N.P. N.P. N.P. N.P. N.P. N.P. N.P. 9 ‐‐ 6

19CPT‐01 CPTu 68 28 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 28 38 ‐12 14 ‐10 2 ‐26 N.P. ‐‐ ‐‐ ‐‐

19CPT‐02 CPTu 79 27 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 27 39 ‐20 8 ‐12 8 ‐28 N.P. ‐‐ ‐‐ ‐‐

19CPT‐03 CPTu 67 25 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 25 35 ‐12 15 ‐10 2 ‐27 N.P. ‐‐ ‐‐ ‐‐

19CPT‐04 CPTu 70 27 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 27 37 ‐12 16 ‐10 2 ‐28 N.P. ‐‐ ‐‐ ‐‐

19SCPT‐01 SCPTu 70 27 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 27 37 ‐24 6 ‐10 14 ‐30 N.P. ‐‐ ‐‐ ‐‐

19SCPT‐02 SCPTu 70 26 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ 26 34 ‐12 18 ‐8 4 ‐30 N.P. ‐‐ ‐‐ ‐‐

CBR‐001 Shallow Grab Sample 3 28 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐

CBR‐002 Shallow Grab Sample 2 25 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐

CBR‐003 Shallow Grab Sample 3 25 ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ *Piezometer installed to depth of 12 feet below ground surface.

N.P. = Not Penetrated Through N.E. = Not Encountered

STRATUM 1: Upper Sand STRATUM 2A: Clay STRATUM 2B: Intermediate Sand STRATUM 3: Lower Sand

SUBSURFACE WATER DEPTHS FROM GROUND SURFACESTRATUM 2A STRATUM 3STRATUM 2BUNCONTROLLED FILL STRATUM 1

-50

-40

-30

-20

-10

0 100 200 300 400 500 600 700 800 900 1,000

-50

-40

-30

-20

-10

0 100 200 300 400 500 600 700 800 900 1,000

(19)

(9) (10) (15) (16)

(10)

(8)

(11)

(17)

(14)

(11)

(9)

(12)

(8)

(7)

(8)

(14)

(9)

(5) (8)

(11) (5) (5)

(7)

(13)

(14)

(16)

(14)

(12)

(15)

(8)

(9)

(8)

(13)

(16)

(20)

(9) (6) (3) (6) (9)

(4)

(15)

(9)

(17)

(18)

(15)

(18)

(20)

(13)

(9)

(11)

(14)

(13)

(5) (8)

(10) (4) (3)

(13) (10) (15)

(7) (5)

(14) (22) (10)

(6) (9)

PROJECT NAME P-197, F35 Hangar and Parking Garage

PROJECT LOCATION MCAS Cherry Point, North Carolina

CLIENT NAVFAC

PROJECT NUMBER 10147721

Distance Along Baseline (ft)

SUBSURFACE DIAGRAM

Profile A-A' - Airfield

Concrete Uncontrolled Fill USCS Silty Sand

USCS High Plasticity Clay USCS Clayey Sand USCS Poorly-graded Sand USCS Poorly-graded Sand with Silt

USCS Poorly-graded Sand with Clay USCS Low Plasticity Clay

Concrete Cement Treated Aggregate

El ev at io n (ft

D

F

- S

TR

AT

IG

R

AP

H

Y

G W

B

SI

ZE

G

IN

T

ST

D

U S

LA

B

- H D

R .G

D T

- 1 0/

/1

:5

- J :\G

EO

TE

C H

\P R

O

JE

C

TS

\N

AV

FA

C

\C H

ER

R

Y

PO

IN

T\

P-

7, F

H

AN

G

AR

A

N D

P

AR

KI

N

G D

EC

K\

G

IN

T\ P-

7.

G

PJ

4880 Sadler Road, Suite 100 Glen Allen, VA 23060

SM

CH

SC

SP

19B-001 N Value

SC

SP-SM

SP

SP-SM

19B-002 N Value

SM

CL

SP-SM

SP

19B-003 N Value

SM

SC

SM

CL

SP-SM

19BMP-001

N Value

SM

19BMP-002

N Value

SM

SP-SM

SM

19BMP-003

N ValueC-1

N Value 0 200 400

Target Depth

Hand Auger

C-1

FIGURE A-5

Stratum 1: Upper Sand

Stratum 2A: Clay Stratum 2B: Intermediate Sand Stratum 3: Lower Sand

SHWT

SHWT

SHWT

SHWT

SHWT SHWT

-30

-20

-10

0 100 200 300 400 500 600 700 800 900 1,000

-50

-40

-30

-20

-10

0 100 200 300 400 500 600 700 800 900 1,000

(19)

(9) (10) (15) (16)

(10)

(8)

(11)

(17)

(14)

(11)

(9)

(12)

(8)

(7)

(8)

(14)

(9)

(5) (8)

(11) (5) (5)

(7)

(13)

(14)

(16)

(14)

(12)

(15)

(8)

(9)

(8)

(13)

(16)

(20)

(9) (6) (3) (6) (9)

(4)

(15)

(9)

(17)

(18)

(15)

(18)

(20)

(13)

(9)

(11)

(14)

(13)

(5) (8)

(10) (4) (3)

(13) (10) (15)

(7) (5)

(14) (22) (10)

(6) (9)

PROJECT NAME P-197, F35 Hangar and Parking Garage

PROJECT LOCATION MCAS Cherry Point, North Carolina

CLIENT NAVFAC

PROJECT NUMBER 10147721

Distance Along Baseline (ft)

SUBSURFACE DIAGRAM

Profile A-A' - Airfield

Concrete Uncontrolled Fill USCS Silty Sand

USCS High Plasticity Clay USCS Clayey Sand USCS Poorly-graded Sand USCS Poorly-graded Sand with Silt

USCS Poorly-graded Sand with Clay USCS Low Plasticity Clay

Concrete Cement Treated…