Soils_and_Foundations_Report_No._04-19.pdf

SOILS AND FOUNDATIONS

REPORT NO. 04-19

PROJECT: NC ERFO FS 2016-1(1)

LANDSLIDE REPAIRS

NANTAHALA AND PISGAH NATIONAL FORESTS

NORTH CAROLINA

US DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

21400 RIDGETOP CIRCLE

STERLING, VA 20166

MAY 2019

TABLE OF CONTENTS

1. INTRODUCTION

1.1. General

1.2. Project Location

1.3. Background

2. SUBSURFACE EXPLORATION PROGRAM

2.1. Drilling and Sampling

2.2. Data Summary

2.3. Laboratory Testing

3. SUBSURFACE CONDITIONS

3.1. Regional Geology

3.2. Findings

3.3. Groundwater

4. DESIGN ANALYSIS AND RECOMMENDATIONS

4.1. Design Alternatives

4.2. Design Analysis

5. CONSTRUCTION SPECIFICATIONS

5.1. General

5.2. Excavations and Foundation Preparation

5.3. Wall Erection

5.4. Backfilling

5.5. Reinforcement Specifications

6. REFERENCES

7. DISCLAIMER/LIMITATIONS CLAUSE

APPENDICES

Appendix A – Figures Appendix B – Boring Location Maps Appendix C – Subsurface Profiles Appendix D – Boring Logs Appendix E – Laboratory Testing Appendix F – Site Photographs

Note: Design changes subsequent to publication of this report and prior to the project’s advertisement will be documented by a memo attached after the title page.

LANDSLIDE REPAIR

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

PAGE 3 OF 12 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

SOILS AND FOUNDATIONS

REPORT NO. 04-19

LANDSLIDE REPAIRS

NANTAHALA AND PISGAH NATIONAL FORESTS

NORTH CAROLINA

1. INTRODUCTION

1.1. General

This report presents the results of the subsurface exploration, laboratory testing, geotechnical analysis, and our evaluations and recommendations for five (5) landslide repairs in Nantahala and Pisgah National Forest, spanning Clay, Macon, Cherokee, and Transylvania counties in western North Carolina

1.2. Project Location

Landslides information is summarized in.

Table 1 Site locations and vicinity maps are included in Appendix A – Figures

Table 1: Summary of landslide sites

Site County National Forest

No. Name Route Mile Post

1 Deep Gap Road 71 4.8 Macon Nantahala NF

2 Ball Creek Road 83 2.3 Macon Nantahala NF

3 Fires Creek Road 340 6.9 Clay Nantahala NF

4 Perry Gap Road 350 3.2 Clay Nantahala NF

5 Davis Creek Road 420 5.0 Cherokee Nantahala NF

1.3. Background

Landslides and embankment failures were observed in many sections following the heavy rain event of March 2016.

2. SUBSURFACE EXPLORATION PROGRAM

2.1. Drilling and Sampling

A subsurface exploration program consisting of soil borings was conducted to characterize subsurface conditions. Drilling was performed by the EFLHD subsurface exploration team between April and June 2018. The program consisted of drilling a total of sixteen (16) soil borings to depths of 2 ft to 50 ft. below

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FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

existing site grades. Field data are summarized in Table 2 and boring locations maps are included in Appendix B.

Table 2: Field Data.

Boring No. Location Northing* Easting* Ground Surface

Elev. (ft)** Depth (ft)

BH-18-01 Route 71, MP 1.70 508494.68 627872.71 3558.0 13.3

BH-18-02 Route 71, MP 4.53 505239.78 635163.82 4192.7 19.7

BH-18-03 Route 71, MP 4.80 504522.84 636460.26 4102.0 13.4

BH-18-03A Route 71, MP 4.80 504598.43 636491.02 4098.0 33.3

BH-18-04 Route 83, MP 0.02 506288.86 675029.95 2239.5 30.0

BH-18-05 Route 83, MP 2.30 499159.29 667642.21 3156.0 50.0

BH-18-05A Route 83, MP 2.30 499235.61 667639.71 3150.0 50.0

BH-18-12 Route 340, MP 6.92 535360.83 569293.87 2982.0 11.0

BH-18-12A Route 340, MP 6.92 535330.81 569234.29 2981.1 4.3

BH-18-12P*** Route 340, MP 6.92 535348.75 569256.99 2981.0 4.1

BH-18-07 Route 350, MP 3.20 519707.63 609974.25 3804.6 25.7

BH-18-07A Route 350, MP 3.20 519620.72 609965.06 3799.0 16.4

BH-18-08 Route 420, MP 5.00 579063.54 489775.62 3289.4 5.9

BH-18-08A Route 420, MP 5.00 578977.46 489855.61 3283.6 5.8

BH-18-10 Route 471, MP 3.30 563146.73 859285.24 2868.9 2.5

BH-18-11 Route 751, MP 1.18 506628.39 668397.88 2619.5 11.3 *Horizontal coordinates referenced to US State Plane Zone 3200 NC (NAD 1983).

**Elevations referenced to north American Vertical Datum of 1988 (NAVD 1988).

***Confirmation Boring

Borings were drilled using a CME 750 drill rig mounted on a rubber tired all-terrain vehicle (ATV).

Boreholes were advanced using 3-¾-inch (inside diameter) hollow stem augers (HSA). The locations were laid out by EFLHD personnel in the field by referencing topographic features, measuring distances from existing surface features, and by using a hand-held GPS equipment.

Soil samples were obtained using a standard split-barrel (split-spoon) sampler driven during Standard Penetration Tests (SPT) in general accordance with ASTM D 1586, Standard Method of Penetration Test and Split Barrel Sampling of Soils. SPT was performed by driving the split-spoon sampler 24 inches under the impact of a 140-pound automatic hammer free falling 30 inches. SPT was generally performed at 2.5-foot interval in the upper 20 feet and at 5-foot intervals thereafter. The number of blows required to advance the sampler through each 6-inch interval was recorded on field boring logs. The number of hammer blows required to advance the split-spoon sampler the middle foot is designated as the “Standard Penetration Resistance” or N value. SPT refusal is defined by achieving 50 blows per 1-inch (or less) of the split-spoon sampler.

Representative portions of the split-spoon samples were preserved in glass jars. The samples were visually classified and logged in the field by the drilling crew team leader. Samples were then delivered to

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CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

PAGE 5 OF 12 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

the EFLHD Materials Testing facility in Sevierville, TN for testing and storage. Details on sampling and sample descriptions are provided in the boring logs included in Appendix D of this report. Boreholes were backfilled with auger cuttings.

2.2. Data Summary

Data collected from the exploratory borings was recorded in the driller’s logs. These data sheets and logs indicate the boring methods, samples attempted and recovered, indications of the presence of various materials such as fines, sands, and gravel, organic matter, and observations of groundwater. The logs also contain interpretations of the subsurface conditions based on the performance of the equipment and cuttings brought to the surface by the drilling tools. Therefore, the field data represent both factual and interpretative information.

The boring logs provided in Appendix D represent a compilation of field and laboratory data and description of the soil samples by a geotechnical engineer. These records occasionally do not include all data recorded on driller’s logs and field data sheets, but do include all information considered relevant to the design and preparation of this report.

Groundwater levels, when encountered, were measured in the boreholes at the times and under the conditions stated in the boring logs. Fluctuations in groundwater level due to seasonal variations, rainfall, temperature, and other factors not evident at the time measurements could be expected.

2.3. Laboratory Testing

Laboratory testing was performed on representative soil samples recovered during the subsurface exploration to aid in the classification, and the evaluation of engineering parameters of the subsurface materials. The following tests were performed on selected samples.

Grain Size Distribution (AASHTO T-11 and T-27) Moisture Content (MC) (AASHTO T-265) Plastic Limit (PL) (AASHTO T-90) Liquid Limit (LL) (AASHTO T-89)

A summary of laboratory test results is shown in Table 3 and copies of the laboratory results are provided in Appendix 3.

Table 3: Summary of laboratory test results.

Boring No.

Sample No.

Depth (ft)

Gravel

Sand

Fines

MC

PL

LL

AASHTO

Classification

BH-18-01 J2/J3 3-7 52.4 38.4 9.2 15.2 NP NP A-1-a

BH-18-01 J4/J5 10-12 23.6 57.3 19.1 31.9 NP NP A-1-b

BH-18-02 J4 8-10 36.8 47.1 16.1 24.0 NP NP A-1-b

BH-18-03 J2 3-5 33.7 51.0 15.3 18.4 NP NP A-1-b

BH-18-03A J6 13-15 12.2 73.9 13.9 19.5 NP NP A-2-4(0)

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PAGE 6 OF 12 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

Boring No.

Sample No.

Depth (ft)

Gravel

Sand

Fines

MC

PL

LL

AASHTO

Classification

BH-18-03A J8 18-20 8.6 74.4 17.0 21.1 NP NP A-2-4(0)

BH-18-04 J2/J3 3-7 31.7 56.0 12.3 21.9 NP NP A-1-b

BH-18-04 J4/J5 8-12 21.7 63.8 14.5 27.6 NP NP A-1-b

BH-18-05 J7 15-17 9.8 67.4 22.8 21.3 NP NP A-2-4(0)

BH-18-05 J10 25-27 0.0 85.6 14.4 18.2 NP NP A-2-4(0)

BH-18-05 J11 30-32 3.2 70.8 26.0 33.4 NP NP A-2-4(0)

BH-18-05A J2/J3 3-7 12.4 65.9 21.7 21.1 NP NP A-2-4(0)

BH-18-07 J4 8-10 10.6 72.3 17.1 8.4 NP NP A-1-b

BH-18-07A J3 5-7 5.6 66.1 28.3 13.4 NP NP A-2-4(0)

BH-18-10 J1 1-3 39.2 49.4 11.4 6.8 NP NP A-1-b

BH-18-11 J2/J3 3-7 60.4 33.6 6.0 7.2 NP NP A-1-a

3. SUBSURFACE CONDITIONS

3.1. Regional Geology

The geologic map of North Carolina (1991) indicates that Sites No. 1, No. 2 and No. 4 are located within the Coweeta group in the Biotite Gneiss formation, and Sites No. 3 and No. 5 are located within the Nantahala and Wehutty formations. The Biotite Gneiss is described as interlayered and intergraded with biotite gneiss, biotite schist, and amphibolite (Brown, 1985). The Nantahala formation includes laminated metasiltstone, schist, and arkosic quartzite (Kish, 1991). Wehutty formation is described as interbedded gray metagraywacke and metaconglomerate with minor interlayers of muscovite schist (Brown, 1985).

The geologic maps are included in Figure 2, Appendix A.

3.2. Findings

A general description of the subsurface conditions encountered during our field exploration is presented below. Subsurface profiles are included in Appendix C. The stratification lines designating the interfaces between soil types on the boring logs and the subsurface represent approximate boundaries. The transition between materials may be gradual. Also, one or more of the units may be absent at specific locations.

The subsurface profile was classified into the following strata based on descriptions on the boring logs and laboratory tests results.

3.2.1. Site No. 1, Route 71, MP 4.8 (Borings BH-18-03 and BH-18-03A)

Gravel surface and base course

The borings encountered a 1.5 ft thick layer of gravel surface and base course .

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Fill

Underneath the base course layer, fill was encountered in both borings and extended to depths of 7.0 to 10 ft below existing site grades. The fill consisted primarily of Silty Sand with Gravel. SPT N-values recorded ranged from 6 to 18 blows per foot (bpf), indicating loose to medium dense relative densities.

Silty Sand

Underneath the fill material, a Silty Sand layer was encountered. N-values ranged from 11 bpf to 50 blow/5”. This layer extended to the termination depths of the soil borings.

3.2.2. Site No. 2, Route 83, MP 2.3 (Borings BH-18-05 and BH-18-05A)

Gravel surface and base course

The borings encountered a 1.0 ft thick layer of gravel surface and base course.

Silty Sand

Underneath the base course material, the borings encountered a 40 ft thick layer of Silty Sand. N-values ranged from 2 to 50 blow/3”45 bpf indicating very loose to very dense relative densities. The layer extended to the termination depths of the soil borings.

3.2.3. Site No. 3, Route 340, MP 6.9 (Borings BH-18-12, BH-18-12A, and BH-18-12P)

Gravel surface and base course

The borings encountered a 1.0 ft thick layer of gravel surface and base course.

Sandy Silt with Gravel

Underneath the base course material, the borings encountered a layer of Sandy Silt with Gravel. N-values ranged from 3 to 50 blow/5”58 bpf indicating very loose to very dense relative densities. This layer extended to auger refusal depths.

3.2.4. Site No. 4, Route 350, MP 3.2 (Borings BH-18-07 and BH-18-07A)

Gravel surface and base course

The borings encountered a 1.0 ft thick layer of gravel surface and base course.

Silty Sand

Underneath the base course material, the borings encountered a Silty Sand layer. N-values ranged from 17 to 50 blow/3” indicating medium dense to very dense relative densities. This layer extended to the termination depths of the soil borings.

3.2.5. Site No. 5, Route 420, MP 5.0 (Borings BH-18-08 and BH-18-08A)

Gravel surface and base course

The borings encountered a 1.0 ft thick layer of road gravel surface and base course.

Fill

Underneath the base layer, fill was encountered in both borings. The fill consisted primarily of poorly graded sand with silt and gravel and extended to auger refusal depths.

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PAGE 8 OF 12 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

3.3. Groundwater

Groundwater was encountered in Borings BH-18-05 and BH-18-05A (site No. 2) at depths of 10 ft and 9 ft below existing site grades, respectively. Changes in groundwater levels should be expected due to topography, seasonal variations, precipitation, evaporation, and surface water runoff.

4. DESIGN ANALYSIS AND RECOMMENDATIONS

4.1. Design Alternatives

Landslides occur as a result of unbalanced pressures along sloping ground. The addition of water worsens the conditions along a slope by increasing the driving forces and in some cases reducing the strength of the in-situ materials. To mitigate slope stability problems, two general approaches can be used. One approach is to reduce the driving forces by reducing weight, flattening the slope, adjusting roadway grading, or by installing surface and subsurface drainage systems. The second approach is to increase the resisting forces by buttressing, adding counterweight fills, adding a retaining structure, or by reinforcing the embankment fill to increase its strength. Based on subsurface conditions, constructability, cost, and our experience with similar projects, two alternatives were considered feasible and effective for he landslides repairs. The alternatives are listed in Table 4:

Table 4: Landslide Repair alternatives

Alt. No. Stabilization System Advantages Disadvantages

1 Horizontal backslope MSE Retaining Structure

Cost effective.

Flexible system that can accommodate varying subsurface conditions, and can tolerate deformations due to poor subsoil foundation conditions.

Simple and rapid construction.

Compaction is required to achieve design strength.

Requires a relatively large excavation for soil reinforcement installation.

Requires high quality imported backfill material.

Road closer would be required for construction.

May require shoring for temporary cut slopes.

2 Soil Nail Wall Small footprint

Less disturbance to existing terrain.

Rapid construction.

Requires specialized equipment and contractors.

Additional QC/QA is required for nails.

Cost

Alternative No. 1 was considered the most cost effective approach.

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CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

PAGE 9 OF 12 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

4.2. Design Analysis

Design of the MSE (Mechanically Stabilized Earth) walls was conducted using limit equilibrium methodology, in general accordance with the design concepts and procedures presented in FHWA Publication FHWA-GEC 011, “Design and Construction of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes,” (2010), and following “AASHTO LRFD Bridge Design Specifications, 8th Ed.”

(2017) design requirements. A summary of soil engineering parameters assumed in the external, internal and global stability analyses is presented in the tables below.

Table 5: Summary of assumed material properties

Site ID Material

Type

Unit Weight

(pcf)

Cohesion (psf)

Internal Friction Angle ϕ

For all sites Granular Backfill 125 0 34°

No. 1 (Route 71, MP 4.8)

Retained Material (Fill) 115-120 0 30° - 34°

Foundation (Silty Sand) 115-120 400-600 30° - 34°

No. 2 (Route 83, MP 2.3)

Retained Material (Silty Sand) 110-115 0 30° - 34°

Foundation (Silty Sand) 115-120 100-300 34° - 36°

No. 3 (Route 340, MP 6.9)

Retained Material (Silty Sand) 115-120 0 30° - 34°

Foundation (Silty Sand/Siltstone/schist rock)

115-120 1,250 34° - 38°

No. 4 (Route 350, MP 3.2)

Retained Material (Silty Sand) 115-120 0 32° - 34°

Foundation (Silty Sand) 115-120 100-300 34° - 36°

No. 5 (Route 420, MP 5.0)

Retained Material (Fill) 115-120 0 30° - 34°

Foundation (Fill) 115-120 0 38° - 40°

A uniform distributed live surcharge load of 250 psf was applied along the travel way to account for traffic loading following (AASHTO-LRFD, 2017) – Section 3.11.6.4.

The selected load factors and combinations for Sites No.1 and No. 2 are presented in Table 6. The factors follow (AASHTO-LRFD, 2017) Section 3.4.1. The resistance factor used for design for both sites are presented in Table 7, following (AASHTO-LRFD, 2017) Section 11.5.7.

Table 6: MES walls design load factors and combinations.

Load Combination EH EV ES LS

Strength I (Max) 1.50 1.35 1.50 1.75

Strength I (Min) 0.90 1.00 0.75 1.75

Service I 1.00 1.00 1.00 1.00

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EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

Table 7: MSE walls design resistance factors.

Analysis Resistance Factor

Sliding Φs: 1.00

Bearing Φb: 0.65

Overall/Global ΦG: 0.75 (FSG:1.30)

Geosynthetic Tensile Resistance ΦT: 0.90

Geosynthetic Pullout Resistance Φp: 0.90

To satisfy the design criteria, the following soil reinforcement general requirements are recommended for Sites No. 1 and No. 2 repair:

Geosynthetic reinforcement type: Uniaxial or Biaxial Geogrid, Type V Minimum Allowable Long-Term Design strength (Tal): 3,000 lb/ft Minimum Ultimate strength (Tult): 6,000 lb/ft Maximum geogrid vertical spacing: 1.5 feet

External and internal stability analysis computations were performed using PTC Mathcad Prime v. 4.0 program, and global stability analysis using the computer program Slide v. 6.0 by Rocscience, Inc.

According to AASHTO 11.5.4.2, a seismic design shall not be considered mandatory for walls located in Seismic Zones 1 through 3, or for walls located in areas where the adjusted Peak Ground Acceleration (PGA) is less than or equal to 0.4g, unless one or more of the following is true:

Liquefaction induced lateral spreading or slope failure, or seismically induced slope failure, due to the presence of sensitive clays that lose strength during the seismic shaking, may impact the stability of the wall for the design earthquake.

The wall supports another structure that is required, based on the applicable design code or specification for the supported structure, to be designed for seismic loading and poor seismic performance of the wall could impact the seismic performance of that structure.

After performing a project seismic evaluation, it was concluded that the retaining structures do not require a seismic evaluation.

5. CONSTRUCTION SPECIFICATIONS

5.1. General

Construction shall be performed following the Standard Specifications for Construction of Roads and Bridges on Federal Highway Projects (FP-14) and the Special Contract Requirements (SCR). Surface runoff should be diverted at the top of the slope to prevent it from flowing over the face. In addition, runoff that is collected above the MSE wall should be channelized or piped outside limits of the repair area.

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FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

5.2. Excavations and Foundation Preparation

All excavations shall be performed according to Subsection 208.03 of FP-14, local, state and federal guidelines. Due to the variability of subsurface profile within the landslide areas, temporary excavation support may be required.

5.3. Wall Erection

Wall should be erected according to Subsection 255.04 and 255.04(b).

5.4. Backfilling

Backfill within the wall reinforcement area shall follow Subsection 255.05 of FP-14. Backfill material should be Granular Backfill (AASHTO M 43, Size Number 57) meeting requirements of subsection 703.03a, and be placed and compacted in accordance with subsection 209.09 and 209.10.

The retaining structure subsurface water drainage system shall follow the specification shown in Subsection 605.03, and 605.04(a). Geotextile filter fabric should be in accordance with Subsection

714.01. It is recommended to use a Class 1, Type B geotextile.

5.5. Reinforcement Specifications

Geogrid reinforcement shall conform Subsection 714.04 of FP-14 specifications. The minimum Nominal Long-Term Strength (Tal) required for construction is of 3,000 lb/ft, or Ultimate Strength (Tult) of 6,000 lb/ft, which represents a Type V geogrid according to Table 714-6.

6. REFERENCES

AASHTO-LRFD. (2017). AASHTO LRFD Bridge Design Specification (8th ed.). Washington, D.C.:

American Association of State Highway and Transportation Officials.

Berg, R. R., Christopher, B. R., & Samtani, N. C. (2010). Design and Construction of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes (Vol. I & II). Washington D.C.: National Highway Institue (NHI), Federal Highway Administration (FHWA), US Department of Transportation.

FHWA. (2014). Standard Specifications For Construction of Roads and Bridges on Federal Highway Projects (FP-14). US Department of Transportation. Washington D.C.: US Department of Transportation.

Weiner, L., & Merschat, C. (1992). Geologic Map of Southwestern North Carolina. North Carolina Geologic Survey.

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STERLING, VA

7. DISCLAIMER/LIMITATIONS CLAUSE

The subsurface explorations and test described in this report have been conducted in accordance with standard practices and procedures (except as specifically noted). The results of these exploration and test represent conditions at the specific locations and dates indicated. Subsurface conditions between these locations may vary. The Geotechnical Design Analyses and Recommendations Sections of this report include interpretations and recommendations developed by the Government in the process of preparing the design. These interpretations are not intended as a substitute for the personal investigation, independent interpretation, and judgment of the Contractor.

Prepared by:

Jonathan Herrera-Roldán, P.E.

Geotechnical Engineer

Reviewed by:

Mounir Abouzakhm, P.E.

Division Geotechnical Engineer

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

STERLING, VA

APPENDICES

Appendix A – Figures

Appendix B – Boring Location Maps

Appendix C – Subsurface Profiles

Appendix D – Boring Logs

Appendix E – Laboratory Testing

Appendix F – Site Photographs

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DEPARTMENT OF TRANSPORTATION

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Appendix A – Figures

NORTH CAROLINA ERFO NC2016-1-FS

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DEPARTMENT OF TRANSPORTATION

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U.S. Department of Transportation Federal Lands Highway Division

Eastern Federal Lands Highway Division Sterling, Virginia

FIGURE NO. 1

Site Location and

Vicinity Maps

STATE PROJECT

SHEET

NO.

TOTAL

SHEETS

NC

NC ERFO FS

2016-1(1) 1 2

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

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U.S. Department of Transportation Federal Lands Highway Division

Eastern Federal Lands Highway Division Sterling, Virginia

FIGURE NO. 2

Geologic Map

STATE PROJECT

SHEET

NO.

TOTAL

SHEETS

NC

NC ERFO FS

2016-1(1) 2 2

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DEPARTMENT OF TRANSPORTATION

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Appendix B – Boring Location Maps

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DEPARTMENT OF TRANSPORTATION

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DEPARTMENT OF TRANSPORTATION

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DEPARTMENT OF TRANSPORTATION

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DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

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DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

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DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

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DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

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DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Appendix C – Subsurface Profiles

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Appendix D – Boring Logs

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Appendix E – Laboratory Testing

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Appendix F – Site Photographs

NORTH CAROLINA ERFO NC2016-1-FS

CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Photo No. 1: FSRD 71, MP 1.70

Photo No. 2: FSRD 71, MP 4.53

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DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Photo No. 3: FSRD 71, MP 4.80

Photo No. 4: FSRD 83, MP 0.02

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CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Photo No. 5: FSRD 83, MP 2.3

Photo No. 6: FSRD 340, MP 6.919

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CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Photo No. 7: FSRD 350, MP 3.20

Photo No. 8: FSRD 420, MP 5.0

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CLAY, CHEROKEE, AND MACON COUNTIES, NORTH CAROLINA

DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

Photo No. 9: FSRD 471, MP 3.3

Photo No. 10: FSRD 751, MP 1.18